# From Tree Fellers to Planters: A Systematic Review of Forest Restoration Initiatives Involving Local Populations in Central Africa

Adrien Peroches, Emilien Dubiez, Adeline Fayolle, Lydie-Stella Koutika, Neville Mapenzi, Cédric Vermeulen, Marc Oswald, Guillaume Lescuyer

► To cite this version:

Adrien Peroches, Emilien Dubiez, Adeline Fayolle, Lydie-Stella Koutika, Neville Mapenzi, et al.. From Tree Fellers to Planters: A Systematic Review of Forest Restoration Initiatives Involving Local Populations in Central Africa. Small-Scale Forestry, 2025, 10.1007/s11842-025-09586-6. hal-05076630

HAL Id: hal-05076630

https://hal.science/hal-05076630v1

Submitted on 6 Jun 2025

HAL is a multi-disciplinary open access
archive for the deposit and dissemination of sci-
entific research documents, whether they are pub-
lished or not. The documents may come from
teaching and research institutions in France or
abroad, or from public or private research centers.

L'archive ouverte pluridisciplinaire HAL, est
destinée au dépôt et à la diffusion de documents
scientifiques de niveau recherche, publiés ou non,
émanant des établissements d'enseignement et de
recherche français ou étrangers, des laboratoires
publics ou privés.

<figure><img src="image_1.png" /></figure>

Distributed under a Creative Commons Attribution 4.0 International License
<figure><img src="image_2.png" /></figure>

# From Tree Fellers to Planters: A Systematic Review of Forest Restoration Initiatives Involving Local Populations in Central Africa

Adrien Peroches¹,²,³✉ · Emilien Dubiez³,⁴ · Adeline Fayolle³,⁵ · Lydie-Stella Koutika⁶ · Neville Mapenzi⁷ · Cédric Vermeulen⁵ · Marc Oswald² · Guillaume Lescuyer³,⁷

Accepted: 17 April 2025

© The Author(s) 2025

## Abstract

In tropical regions, forest restoration is regarded as a valuable strategy for mitigating the impacts of global warming and improving the livelihoods of local populations. Although numerous international donors have provided substantial financial support for forest restoration in the tropics, the strategies and effectiveness of these initiatives in Central Africa have been poorly documented and never synthesised. To this end, we carried out a review of forest restoration initiatives involving local populations in Central Africa, following a systematic literature review approach. We retained 64 publications, pertaining to 26 initiatives that predominantly applied agroforestry techniques, used exotic species, and were implemented in the Democratic Republic of Congo (n=12 initiatives), Cameroon (n=11), Cameroon & Gabon (n=1), Rwanda (n=1), and Central African Republic (n=1). This review shows that: (1) most forest restoration initiatives were based on pre-established technical approaches, mainly agroforestry or plantations of exotic species; (2) there was a lack of monitoring and data sharing; (3) local people were rarely consulted on the choice of technical approach and (4) prior consent, proposed land arrangements and benefit sharing were seldom mentioned. Based on our analysis, the two key issues for donors and project managers are: (1) building real partnerships with local people, which can mean compromising and downgrading objectives, and (2) monitoring their experiences and sharing the findings to improve future sustainable forest restoration initiatives.

**Keywords** Tree plantations · Agroforestry · Assisted natural regeneration · Smallholders · Congo basin · Tropical forest restoration
**Introduction**

In recent decades, the Congo Basin (covering around 200 million ha of land) has been shown to hold the greatest capacity for storing carbon (-0.61 Gt CO₂ per year), ahead of the Amazon (-0.1 Gt CO₂) and Southeast Asia, which emitted more CO₂ than it absorbed (+0.49 Gt CO₂) (Dalimier et al. 2022; Harris et al. 2021). However, today Africa is the continent with the largest net forest loss in the world, and this phenomenon is accelerating. An average of 1.79 million ha of forest cover was lost each year over the period 2015-19 in Central Africa, against 1.36 million ha in average each year during the previous decade, 2005–2015 (Vancutsem et al. 2021). Over the last decade (2010–2020), the Democratic Republic of Congo (DRC) was the second country in the world (after Brazil) in terms of forest loss, with more than 1 million ha in average lost per year (FAO 2020). In this context, forest restoration is seen as a possible solution, alongside the fight against deforestation, to limit, compensate for or reverse the trend of biodiversity loss and the disappearance of forest ecosystems (Bastin et al. 2019; Chazdon 2008; Lewis et al. 2019).

In Central Africa, the main direct driver of deforestation is the expansion of shifting agriculture to produce food and wood fuel (Curtis et al. 2018; Shapiro et al. 2023; Tchatchou et al. 2015). According to Tyukavina et al. (2018), 84% of deforested land in the Congo Basin has been cleared by farmers cultivating small areas and practising slash-and-burn agriculture which relies on long fallow periods that have drastically decreased in these last decades as a result of demographic pressure. Deforestation is mostly increasing in small patches of fragmented and degraded forests that contain little biomass (Shapiro et al. 2023) and where natural fires (hardly identified by satellite imagery) probably play a role in addition to anthropic factors (Curtis et al. 2018; Shapiro et al. 2023). Until now, public policies in the region have failed to prevent deforestation and forest degradation (Guizol et al. 2022; Tegegne et al. 2016). If no remedial action is taken, Vieilledent et al. (2022) estimate that Central Africa will lose more than 50% of its current forest cover by 2100, with drastic consequences for carbon stocks and sequestration (Harris et al. 2021), flora and fauna found across the region (Fonteyn et al. 2023; Shapiro et al. 2021) and people's livelihoods (Gillet et al. 2016).

Deforestation and degradation predominate in the most accessible areas with a high population density, like the peripheries of cities or near main access ways such as road and river networks (Gillet et al. 2016), in the so-called “rural complex” of Shapiro et al. (2023). These areas are not allocated by states in contrasts to forest concessions for timber production or protected areas (which together cover 72 million ha of the Congo Basin) (Dalimier et al. 2022; Lhoest 2020). This “rural complex”, includes community forests (around 2 million ha) (Lhoest 2020), i.e., forests managed by local people on behalf of the state and other areas (more than 100 million hectares) (Dalimier et al. 2022; Lhoest 2020), where there is an overlap between state laws and customary rules governing access to and use of natural resources (Karsenty and Assembe 2010; Vermeulen et al. 2011). This management by the local population itself does not always succeed in achieving sustainability, as shown by the example of the outskirts of Kinshasa (Gond et al. 2016).

<figure><img src="image_3.png" /></figure>
Forest restoration is a method that employs various approaches (assisted natural regeneration, plantations, agroforestry, etc.) with the aim, in a delimited territory, of limiting the degradation of an already slightly degraded forest ecosystem or, conversely, restoring the ecological functionalities of a degraded ecosystem, while also improving the livelihoods of local populations (Besseau et al. 2018; Chazdon 2008; Chazdon and Brancalion 2019; Gann et al. 2019; Guizol et al. 2022). Over the last decade, a strong interest in forest restoration has emerged thanks to the UN Decade on Ecosystem Restoration, the Bonn Challenge, the REDD+ process, AFR100 initiative, Kunming-Montreal Global Biodiversity Framework and various other campaigns to plant trillions of trees (Holl and Brancalion 2022; Martin et al. 2021; UNEP 2022). Relating to the second target of the Kunming-Montreal Global Biodiversity Framework, the Bonn Challenge and the AFR100 initiative, the Central African Forests Commission (COMIFAC), responsible for coordinating efforts related to forest and environmental matters in the region, has issued a political commitment to restore 25% of degraded lands by 2025 (Guizol et al. 2022).

At the scale of the African continent, about 60% of the land with low-cost restoration potential consist of a mosaic of land uses (e.g., small settlements or small areas of cropland, pasture, recovering forests or shifting cultivation) (Shyamsundar et al. 2022). Expanding the body of evidence regarding the integration of local populations in forest restoration processes is a priority (Gnacadja and Vidal 2022; Guizol et al. 2022; Marshall et al. 2022). Indeed, although a vast literature exists on participatory approaches to involve local stakeholders in natural forest management (Borrini-Feyarabend et al. 2000; Buttoud et al. 2016), these approaches remain infrequently or unconvincingly implemented in forest restoration initiatives across the global tropics (Chazdon 2008; Chazdon and Brancalion 2019; Gann et al. 2019; Herbohn et al. 2023; Holl and Brancalion 2020). More broadly, research on the recovery of forest ecosystem services, i.e., ecological succession in secondary forests, has grown significantly over the past 10 years in the Neotropics (Chazdon et al. 2017; Poorter et al. 2016, 2021). Though a vast amount of research is being conducted on monitoring and mapping tree cover loss and its causes (Achard et al. 2007; Curtis et al. 2018; Hansen et al. 2013; Mayaux et al. 2003; Tyukavina et al. 2018; Vancutsem et al. 2021; Vieilledent et al. 2022), only a few initiatives focus on reversing the ongoing deforestation/degradation in the Global South (Martin et al. 2021), and even less involve local populations. This knowledge gap is particularly notable in Central Africa, compared to Amazonia or Southeast Asia (Fagan et al. 2022; Ota et al. 2017).

In this study, we reviewed the existing literature (including peer-reviewed publications and grey literature) on forest restoration initiatives involving local populations in Central Africa. First, the relevant initiatives were contextualised according to location, date, number of related publications, donors, implementers, expected benefits and, finally, the planted area or the number of planted trees. Second, we tested for differences in the technical approach (notably the type of species and the type of restoration) adopted by the initiatives based on their geographical area, and third, we analysed the level of local population participation in these initiatives. The success of forest restoration hinges primarily on the chosen technical approach and the degree of local population participation (Chazdon 2008).
# Methods

## Research Strategy

A systematic literature review was conducted to gain a comprehensive understanding of the forest restoration initiatives in Central Africa that explicitly involved local populations. A systematic literature review is a structured method of searching, screening, selecting, appraising and summarising the results of previous research in order to answer a specific research question (Greenhalgh et al. 2018). Our research strategy involved querying reference databases using the following inclusion criteria, in both English and French: (i) forest restoration, (ii) engaging the local populations and (iii) located in the countries belonging to the COMIFAC, namely Angola, Burundi, Cameroon, Central African Republic (CAR), Chad, Congo, Democratic Republic of Congo, Equatorial Guinea, Gabon, Rwanda, and São Tomé e Principe (Fig. 1). The details of our review process were included in a published protocol (Peroches et al. 2023).

## Selection Process

In January 2023, we ran a search query in Scopus and Web of Science Core Collection and applied to titles, abstracts, and keywords from 1960 to the present, resulting in a batch of 389 articles (Fig. 1). A total of 78 documents, mostly grey literature (technical or evaluative reports from NGOs or consulting firms) deemed relevant (including a forest restoration initiative in Central Africa with local populations) by the co-authors were added to this batch. All articles published in English or French were sorted (n=467): first, by deleting duplicates (n=38 duplicates removed, n=429 articles and reports kept), second, by screening titles and abstracts (n=295 articles and reports excluded, n=134 kept) and third, by reading the whole paper (n=77 articles and reports excluded, n=57 kept). Peer-review articles or documents coming from the grey literature were considered relevant if they included, at least, a forest restoration action performed with a local population in Central Africa. The last step of the selection process entailed checking the references cited in the selected articles and reports, which led to the identification of 41 more records. After the application of the three eligibility criteria to the additional texts only seven were considered relevant (n=36 articles and reports excluded). Finally, 64 studies were selected, including 46 scientific articles, 2 working papers and 16 technical reports or guides (Fig. 1).

## Article Analysis

For all articles and reports, we collected the year of publication, the topic of the publishing journal, the geographic location of the study, the type of restoration (agroforestry, forest plantation or assisted natural regeneration), the type of species (native, exotic or mixed), the planted area and/or the number of trees planted, the monitoring factors and the strategies to involve local populations (including prior consent, proposed land arrangements and benefit sharing).
<table><caption>**Fig. 1** Study diagram (preferred reporting items for systematic reviews and meta-analyses—PRISMA) showing the flow of information through the different phases of the systematic review (adapted from Moher et al. 2010)</caption><thead><tr><th>Criteria</th><th colspan="2">Search query</th></tr></thead><tbody><tr><td>What ?</td><td colspan="2">"restauration forestière*" OR "réhabilitation forestière*" OR "reconstitution forestière*" OR "reboisement*" OR reforestation* OR "régénération naturelle assistée" OR "plantations forestières*" OR agroforesterie* OR "gestion forestière*" OR "forest restoration*" OR "forest reclamation*" OR "forest rehabilitation*" OR "reconstitution offorest*" OR reforestation* OR "natural assisted regeneration*" OR "forest plantations*" OR agroforestry* OR "forest management*"</td></tr><tr><td>Who ?</td><td>A<br>N<br>D</td><td>"populations locales*" OR "communautés locales*" OR "communauté villageoise*" OR communauté* OR métayer* OR fermier* OR agriculteur* OR villageois* OR "local populations*" OR community* OR "local communities*" OR "village communities*" OR farmer* OR smallholder* OR agriculteur* OR sharecropper* OR villager*</td></tr><tr><td>Where ?</td><td>A<br>N<br>D</td><td>"Afrique centrale" OR COMIFAC OR Burundi OR Cameroun OR Congo OR Gabon OR Guinée-équatoriale OR République centrafricaine OR RCA OR RDC OR République Démocratique du Congo OR Rwanda OR Sao Tomé-et-Principe OR Tchad OR "Central Africa" OR Cameroon OR "Equatorial Guinea" OR "Central African Republic" OR CAR OR DRC OR "Democratic Republic of Congo" OR "Sao Tome and Principe" OR Chad</td></tr><tr><td>Date</td><td colspan="2">1960s to 2023</td></tr></tbody></table>

<figure><img src="image_4.png" /></figure>
To identify possible differences in the forest restoration strategies depending on their location or the techniques used, four chi-square tests were carried out using the R open environment. The forest restoration initiatives were grouped into five geographic areas to test for spatial differences in their stated objectives, methods and the tree species used. In addition, the association between the type of species and the restoration methods used was also tested. Given the small sample available (n=26 initiatives), the confidence interval used was 90%.

The involvement of local populations in the forest restoration initiatives was examined from two perspectives, during the project design and during the project implementation (Arnstein 1969; Buttoud et al. 2016; d'Aquino and Seck 2001). Firstly, for the design phase, the involvement of local populations was determined by their level of choice for technical options, in terms of location to be reforested (ranging from one mandatory site to several optional sites) and species (ranging from one mandatory species to several optional species). Secondly, for the implementation phase, the involvement of the population was assessed according to their level of autonomy within the reforestation initiative's project activities, ranging from simply raising awareness to full participation in restoration actions. Thus, the selected forest restoration projects were placed on a graph along these two axes of analysis.

# Results

## Temporal and Geographical Scope

During the systematic review process, we identified 26 different forest restoration initiatives involving local populations in Central Africa, these were described in 58 publications, and six reports, i.e., technical guides on forest restoration in the Great Lakes region (Molenaar and Kessler 2008; Smith-Dumont et al. 2012, 2015; Yan-gambi-Bosunga 2016) and studies regarding the institutional context of the DRC and Cameroon (Dkamela 2012; Foundjem-Tita et al. 2013). Forest restoration involving local populations in Central Africa has been little studied and is a recent topic. The first recorded publication dates from 2000 (Fondoun and Tiki Manga 2000), it was published in the review *Agroforestry Systems* and describes indigenous farmers using assisted natural regeneration (ANR) in Cameroon. We note an increasing interest in recent years (87% of records since 2010). Most of the records were published in jour-nals devoted to forestry (52%), agriculture/agronomy (19%) or agroforestry (14%) while recent interest from other disciplines (since 2012) is also perceptible (Fig. 2).

The 26 forest restoration initiatives identified mostly encompass four areas/ regions of Central Africa: (i) the Grassfields area in Cameroon (Northwest, South-west and West regions), (ii) the dense forest area of Cameroon (Center, Eastern and Southern regions), (iii) the periphery of Kinshasa in the DRC (Kinshasa, Kongo Cen-tral, Kwango and Kwilu provinces) and (iv) the Great Lakes region straddling the South and North Kivu in the DRC and Rwanda (Fig. 3). According to these results, vast areas in Central Africa remain overlooked in terms of tropical forest restoration efforts.

<figure><img src="image_5.png" /></figure>
<figure><img src="image_6.png" /><figcaption>**Fig. 2** The cumulated number of published articles and reports about forest restoration with local populations in Central Africa from 1960 to January 2023. Colours indicate the topic of publication, with forestry in green, agroforestry in orange, agriculture/agronomy in blue, ecology and environment in yellow and politics and economics in purple. (Color figure online)</figcaption></figure>

<figure><img src="image_7.png" /><figcaption>**Fig. 3** Location of the 26 forest restoration initiatives involving local populations in Central Africa and the type of species and restoration methods used</figcaption></figure>
## Objectives

The primary objectives of the forest restoration initiatives involving local populations were economic. Based on the 26 initiatives analyzed, the most cited objectives were: the diversification and increase of rural incomes (16 initiatives), followed by sustainable wood fuel production (13 initiatives). Environmental issues (slowing forest or biodiversity degradation and the restoration or protection of soils) were less frequently cited (8 initiatives), as were other productivity objectives such as sustainable non-wood forest products (NWFP) and sustainable timber production.

The initiatives' objectives differed according to geographic area (P-value = 0.072). In the periphery of Kinshasa (Bisiaux et al. 2009; Peltier et al. 2014; Péroches et al. 2019; Proces et al. 2017) and the Great Lakes region: including North Kivu, South Kivu (Bouyer et al. 2013; GIZ 2020a) and Rwanda (Bucagu et al. 2013; Iiyama et al. 2018a, b; Kiyani et al. 2017; Mukuralinda et al. 2016; Ndayambaje et al. 2012, 2013; Noeldeke et al. 2022; Stainback et al. 2012), the main expected benefits were sustainable wood fuel production, positive impacts on soils and the diversification or increase of rural incomes. In contrast, in both the Grassfields and dense forest areas of Cameroon, the restoration initiatives mostly focused on the sustainable production of timber and NWFP (Awazi et al. 2020, 2021; Njoukam et al. 2013; Robiglio et al. 2012; Semereab 2006; Temgoua et al. 2011).

## Donors

Forest restoration initiatives by local populations in Central Africa have been largely subsidised by public development aid agencies (62% of all initiatives). Among the 26 relevant initiatives, nine were funded by the European Union, three by the French development agency, two by the German development agency, one by the United Kingdom development agency, one by the Danish development agency and one by the World Bank. In Rwanda, the development of agroforestry is partially supported by public funding and nine articles examine the application of this public support to agroforestry (Table 1; Fig. 3). However, most public initiatives are particularly difficult to detect since they are poorly documented, particularly in international journals.

Finally, in Cameroon, we identified three spontaneous local practices (defined as initiatives originating from the local populations themselves) which had not benefited from direct support from an external structure. These three initiatives were: agroforestry for cocoa production (Alemagi et al. 2015; Essouma et al. 2020; Folefack and Darr 2021; Jagoret et al. 2009, 2014), ANR in the dense forest area (Carriere 2002; Fondoun and Tiki Manga 2000; Robiglio et al. 2012) and agroforestry based on native and exotic species (sometimes in association with animals) in the Grassfields area (Awazi et al. 2020, 2021; Kimengsi and Ngu 2022; Nkamleu and Manyong 2005; Temgoua et al. 2011).

## Implementers

Few forest restoration initiatives by local populations in Central Africa have been led by national structures (only 31% of all initiatives). Then, among the 31 imple-

<figure><img src="image_8.png" /></figure>
menters of the 26 relevant initiatives, we found eight international NGOs (against four national NGOs), five international research centres or universities (against one national university), four international companies (against two national private companies), one international cooperation agency (against two national public programs or agencies) and finally three initiatives are implemented with no external support (Table 1). These implementers are likely to work in different ways with centralised, decentralised, or deconcentrated government administrations, producer groups or local NGOs, but little information is available in the literature.

## Forest Restoration Approaches

Eight different approaches to forest restoration were identified, based on planting techniques (ANR, forest plantation or agroforestry) and type of planted species (native, exotic, or a mix of both). The most common planting method used was agroforestry (implemented in 16 initiatives). We did not find any significant difference in methods used between regions (*P*-value=0.181). Agroforestry was significantly more associated with exotic species than reforestation or ANR (*P*-value=0.038). Native species were used in five initiatives, a mix of both native and exotic species in four initiatives, and exotic species in nine initiatives. Initiatives using exotic species were mostly located in the periphery of Kinshasa and relied on the “Mampu System” based on *Acacia spp*. (Table 1; Fig. 3). In this sequential agroforestry system, farmers plant *Acacia auriculiformis* or *A. mangium* between cassava rows, and sometimes mixed with maize, thus combining crop production in the first years with fuelwood production after eight years, when the trees are harvested, and after which burning is used to promote seed germination (Bisiaux et al. 2009; Dubiez et al. 2018; Proces et al. 2017).

Nine initiatives mentioned reforestation actions by means of tree plantations: three using native species in Cameroon and the DRC, five mixing native and exotic species in Cameroon and one using exotic species, in North Kivu. Finally, ANR was promoted in five initiatives: in the dense forest area of Cameroon, CAR and the periphery of Kinshasa (Table 1; Fig. 3).

The types of species employed differed significantly among regions (*P*-value=0.003). Exotic species were mostly promoted in the periphery of Kinshasa, although a mix of exotic and native species was used in the Great Lakes and Grassfields areas. Finally, in the dense forest area of Cameroon, native species were preferred (Table 1; Fig. 3).

## Planted Areas and Trees

Of the 26 initiatives identified, only 18 mentioned a restored area or the number of trees planted (Fig. 4). A total of 26,475 ha of plantation was reported, almost exclusively in the DRC (96.9%). Most of these plantations target wood fuel production and correspond to the agroforestry “Mampu system” described earlier (85.7%), and that has been mostly implemented in the periphery of Kinshasa, and specifically on the Batékés plateau (Bisiaux et al. 2009; Proces et al. 2017; Reyniers 2014, 2019; Sylvatrop & SalvaTerra 2021). The second significant planted area reported was in
<figure><img src="image_9.png" /></figure>

<table><caption>**Table 1** General description of the 26 forest restoration initiatives involving local populations and based in central Africa</caption><thead><tr><th rowspan="2">Country</th><th rowspan="2">Name</th><th rowspan="2">Donor(s)</th><th rowspan="2">Implementer(s)</th><th rowspan="2">Stated objective(s) of the project</th><th rowspan="2">Forest restoration method promoted</th><th colspan="2">Plantation results</th><th colspan="2">Monitoring</th><th rowspan="2">References</th></tr><tr><th>Area (ha)</th><th>Number of trees</th><th>Technical parameters</th><th>Socio-economic parameters</th></tr></thead><tbody><tr><td rowspan="10">DRC</td><td rowspan="10">Mampu</td><td rowspan="10">EU</td><td rowspan="10">Hanns-Seidel Foundation (German NGO) and CADIM (DR Congo NGO)</td><td>Sustainable wood fuel production; Restoration of soil fertility; Diversification and/or increase of rural incomes</td><td>Agroforestry with <i>Acacia spp.</i></td><td>8,000</td><td>NA</td><td>Density: 66 to 3,889 stems/ha with a mean of 1,500 stems/ha<br/>Growth: 1.23 cm<br/>DBH/year<br/>Productivity: 14.5 wood tons/ha/year</td><td>NA</td><td>(Bisiaux et al. 2009; Kachaka et al. 2020; Paul and Fraser 2014; Proces et al. 2017; Tassin et al. 2012)</td></tr><tr><td>Sustainable wood fuel production; Restoration of soil fertility; Diversification and/or increase of rural incomes</td><td>Agroforestry with <i>Acacia spp.</i></td><td>4,200</td><td>NA</td><td>NA</td><td>NA</td><td>(Proces et al. 2017)</td></tr><tr><td>Ntsio</td><td>Hanns-Seidel Foundation (German NGO)</td><td>Sustainable wood fuel production; Restoration of soil fertility; Diversification and/or increase of rural incomes</td><td>Agroforestry with <i>Acacia spp.</i></td><td>4,200</td><td>NA</td><td>NA</td><td>NA</td><td>(Proces et al. 2017)</td></tr></tbody></table>
<table><caption>**Table 1 (continued)**</caption><thead><tr><th rowspan="2">Country</th><th rowspan="2">Name</th><th rowspan="2">Donor(s)</th><th rowspan="2">Implementer(s)</th><th rowspan="2">Stated objective(s) of the project</th><th rowspan="2">Forest restoration method promoted</th><th rowspan="2">Plantation results published Area (ha)</th><th rowspan="2">Number of trees</th><th colspan="2">Monitoring</th><th rowspan="2">References</th></tr><tr><th>Technical parameters</th><th>Socio-economic parameters</th></tr></thead><tbody><tr><td>Makala</td><td>EU</td><td>CIRAD (French Research Centre), CIFOR (International Research Centre) Gembloux AgroBio Tech and ERAIFT (Belgian and DR Congo Universities) and Hanns-Seidel Foundation (German NGO)</td><td>Sustainable wood fuel production; Deceleration of forest degradation processes; Diversification and/or increase of rural incomes</td><td>Agroforestry with <i>Acacia spp.</i>; Re-forestation with native species; Assisted natural regeneration; Forest fallow protection</td><td>1,365 agroforestry and 19 (ANR) reforestation</td><td>2,046</td><td>Maintenance rate: 23% of the agroforestry area planted with <i>Acacia spp.</i>; 0% of native species plantations Mortality rate: 29-91% depending on the conservation technique for ANR; 34% for agroforestry with <i>Acacia spp.</i> 64% for native species plantations Productivity: 43 months after clearing, ANR plots contain 44% more biomass than plots without ANR</td><td>Adoption level: 0-92% depending on the type of farm</td><td>(Nis-mundele Nkondo et al. 2010; Peltier et al. 2014; Péroches et al. 2019; Proces et al. 2017; Vermeulen et al. 2011)</td></tr></tbody></table>
<table><caption>**Table 1 (continued)**</caption><thead><tr><th rowspan="2">Country</th><th rowspan="2">Name</th><th rowspan="2">Donor(s)</th><th rowspan="2">Implementer(s)</th><th rowspan="2">Stated objective(s) of the project</th><th rowspan="2">Forest restoration method promoted</th><th rowspan="2">Plantation results published Area (ha)</th><th colspan="2">Monitoring</th><th rowspan="2">References</th></tr><tr><th>Number of trees</th><th>Technical parameters</th><th>Socio-economic parameters</th></tr></thead><tbody><tr><td>Ibi-Terroir and Sud Kwan mouth Novacel</td><td>World Bank and private funds</td><td>Novacel (DR Congo Private Company) and GI-Agro (Belgian NGO)</td><td>Sustainable wood fuel production; Deceleration of forest degradation processes; Diversification and/or increase of rural incomes</td><td>Agroforestry with <i>Acacia spp.</i></td><td>288.5</td><td>NA</td><td>NA</td><td>Economics: 500 USD/year/household</td><td>(ONFI &amp; Novacel 2012; Paul and Fraser 2014; Reyniers 2014, 2019; Reyniers et al. 2015)</td></tr><tr><td>Gungu</td><td>EU</td><td>Hanns-Seidel Foundation (German NGO)</td><td>Sustainable wood fuel production; Restoration of soil fertility; Diversification and/or increase of rural incomes</td><td>Agroforestry with <i>Acacia spp.</i></td><td>1,800</td><td>NA</td><td>NA</td><td>NA</td><td>(Proces et al. 2017)</td></tr></tbody></table>

<figure><img src="image_10.png" /></figure>
<table><caption>Table 1 (continued)</caption><thead><tr><th rowspan="2">Country</th><th rowspan="2">Name</th><th rowspan="2">Donor(s)</th><th rowspan="2">Implementer(s)</th><th rowspan="2">Stated objective(s) of the project</th><th rowspan="2">Forest restoration method promoted</th><th rowspan="2">Plantation results published Area (ha)</th><th rowspan="2">Number of trees</th><th colspan="2">Monitoring</th><th rowspan="2">References</th></tr><tr><th>Technical parameters</th><th>Socio-economic parameters</th></tr></thead><tbody><tr><td>DEFIV-DA-FOMA</td><td>EU</td><td>GRET (French NGO)</td><td>Sustainable wood fuel production; Restoration of soil fertility; Diversification and/or increase of rural incomes</td><td>Agroforestry with <i>Acacia spp.</i></td><td>14.5</td><td>NA</td><td>NA</td><td>NA</td><td>NA</td><td>(Proces et al. 2017)</td></tr><tr><td>AFODEK</td><td>EU</td><td>GRET (French NGO) and Nature+ (Belgian NGO)</td><td>Sustainable wood fuel production; Restoration of soil fertility; Diversification and/or increase of rural incomes</td><td>Agroforestry with <i>Acacia spp.</i></td><td>1,500</td><td>NA</td><td>NA</td><td>NA</td><td>NA</td><td>(Proces et al. 2017)</td></tr></tbody></table>
<table><caption>**Table 1 (continued)**</caption><thead><tr><th rowspan="2">Country</th><th rowspan="2">Name</th><th rowspan="2">Donor(s)</th><th rowspan="2">Implementer(s)</th><th rowspan="2">Stated objective(s) of the project</th><th rowspan="2">Forest restoration method promoted</th><th colspan="2">Plantation results published</th><th colspan="2">Monitoring</th><th rowspan="2">References</th></tr><tr><th>Area (ha)</th><th>Number of trees</th><th>Technical parameters</th><th>Socio-economic parameters</th></tr></thead><tbody><tr><td></td><td>Pilot integrated REDD+Luki</td><td>EU</td><td>WWF DRC (International and Congolese NGOs)</td><td>Sustainable wood fuel production; Deceleration of forest degradation processes; Diversification and/or increase of rural incomes</td><td>Agroforestry with Acacia spp.; Agroforestry with native species</td><td>NA</td><td>NA</td><td>NA</td><td>NA</td><td>(Bandi et al. 2020, 2022)</td></tr><tr><td></td><td>EcoMakala</td><td>EU</td><td>WWF DRC and BE (International, Congolese and Belgian NGOs)</td><td>Sustainable wood fuel production; Deceleration of forest degradation processes; Diversification and/or increase of rural incomes</td><td>Reforestation with exotic species (mostly <i>Eucalyptus spp.</i>, Acacia spp. and <i>Grevillea spp.</i>)</td><td>3,580</td><td>NA</td><td>Density: high density (up to 10,000 stems/ha)<br>Productivity: 6 to 50 m3/ha/year, with a mean at 20 m3/ha/year</td><td>NA</td><td>(Bouyer et al. 2013; lejeune et al. 2013; Smith-Dumont et al. 2017)</td></tr></tbody></table>

<figure><img src="image_11.png" /></figure>
<table><caption>**Table 1 (continued)**</caption><thead><tr><th>Country</th><th>Name</th><th>Donor(s)</th><th>Implementer(s)</th><th>Stated objective(s) of the project</th><th>Forest restoration method promoted</th><th>Plantation published Area (ha)</th><th>Number of trees</th><th>Monitoring</th><th>Technical parameters</th><th>Socio-economic parameters</th><th>References</th></tr></thead><tbody><tr><td></td><td>Forests and Biodiversity Program</td><td>GIZ</td><td>GIZ (German Cooperation Agency)</td><td>Sustainable wood fuel production; Decel-eration of forest degradation processes; Diversifica-tion and/or increase of rural incomes</td><td>Reforest-ation with native and exotic species; Assisted natural regeneration</td><td>2,785</td><td>NA</td><td>Productivity: 5 to 10 m3/ha/year of mixed plantations (native and exotic species)</td><td>USD in economic volume created in 15 years due to wood and wood fuel production</td><td>Economics: 800,000</td><td>(GIZ 2013, 2020a, b)</td></tr><tr><td></td><td>Ebenezer Ministries International</td><td>King-dom Giving Fund</td><td>Ebenezer Ministries International (International NGO)</td><td>Decel-eration of forest degradation processes; Diversifica-tion and/or increase of rural incomes</td><td>Agrofor-estry with exotic and native species</td><td>NA</td><td>165,000</td><td>NA</td><td></td><td>Adoption level: 30% of the local popula-tion participated</td><td>(Sabin et al. 2019)</td></tr></tbody></table>
<figure><img src="image_12.png" /><figcaption>**Table 1 (continued)**</figcaption></figure>

<table><thead><tr><th>Country</th><th>Name</th><th>Donor(s)</th><th>Implementer(s)</th><th>Stated objective(s) of the project</th><th>Forest restoration method promoted</th><th>Plantation results published Area (ha)</th><th>Number of trees</th><th>Monitoring</th><th>References</th></tr></thead><tbody><tr><td>PROFEAAC</td><td>FFEM</td><td>CIFOR (International Research Centre) and CIRAD (French Research Centre)</td><td></td><td>Deceleration of forest degradation processes; Sustainable wood and NWF production</td><td>Reforestation with native species</td><td>3.8</td><td>NA</td><td>Maintenance rate: 34% of plantations well maintained, 48% fairly-well maintained and 18% non-maintained</td><td>(Botulu et al. 2023)</td></tr><tr><td>Rwanda</td><td>Various public incitation's</td><td>Rwanda Ministry of Agriculture and various donors</td><td>Public actors</td><td>Sustainable wood fuel production; Restoration of soil fertility; Erosion control; Sustainable wood production; Diversification and/or increase of rural incomes</td><td>Agroforestry with native and exotic species</td><td>NA</td><td>NA</td><td>Adoption level: 42% of respondents own woodlots. Economics: 331 USD/year/household which is more than other farmers (297 USD/year/household on average)</td><td>(Bucagu et al. 2013; Iiyama et al. 2018a, b; Kiyani et al. 2017; Ndayambaje et al. 2012, 2013; Noeldeke et al. 2022; Stainback et al. 2012)</td></tr></tbody></table>
<table><caption>**Table 1 (continued)**</caption><thead><tr><th rowspan="2">Country</th><th rowspan="2">Name</th><th rowspan="2">Donor(s)</th><th rowspan="2">Implementer(s)</th><th rowspan="2">Stated objective(s) of the project</th><th rowspan="2">Forest restoration method promoted</th><th rowspan="2">Plantation results published Area (ha)</th><th rowspan="2">Number of trees</th><th colspan="2">Monitoring</th><th rowspan="2">References</th></tr><tr><th>Technical parameters</th><th>Socio-economic parameters</th></tr></thead><tbody><tr><td rowspan="2">Cameroon</td><td rowspan="2">Participatory Tree Domestication</td><td>EU IFAD USDA</td><td>World Agroforestry centre (International Research Centre)</td><td>Diversification and/ or increase of rural incomes; Restoration of soil fertility; Sustainable wood and NWFP production</td><td>Agroforestry with native species</td><td>NA</td><td>122,500</td><td>NA</td><td>Adoption level: 68.8% of people interviewed planted trees</td><td>(Asaah et al. 2011; Grande et al. 2012; Gyau et al. 2012; Tchoundjeu et al. 2010)</td></tr><tr><td>Study of spontaneous local Practices</td><td>NA</td><td>Local people</td><td>Diversification and/ or increase of rural incomes</td><td>Agroforestry with exotic and native species (sometimes in association with animals)</td><td>NA</td><td>Density: high density (up to 20,000 stems/ ha)<br/>Growth: 0.9 cm DBH/year for Canarium schweinfurthii, 0.5 to 1.2 cm DBH / year for Polyscias fulva, 0.55 to 0.8 cm DBH / year for Entandrophragma candellei and 1.2 to 2.5 cm DBH / year for Podocarpus latifolius</td><td>Adoption level: 56.2% of interviewed people practiced agroforestry or forest plantation<br/>Economics: 1.6 to 4.5 USD per wood stick</td><td>(Awazi et al. 2020, 2021; Kimengsi and Ngu 2022; Nkamleu and Manyong 2005; Temgoua et al. 2011)</td></tr></tbody></table>
<figure><img src="image_13.png" /></figure>

<table><caption>**Table 1 (continued)**</caption><thead><tr><th rowspan="2">Country</th><th rowspan="2">Name</th><th rowspan="2">Donor(s)</th><th rowspan="2">Implementer(s)</th><th rowspan="2">Stated objective(s) of the project</th><th rowspan="2">Forest restoration method promoted</th><th rowspan="2">Plantation results published Area (ha)</th><th rowspan="2">Number of trees</th><th colspan="2">Monitoring</th><th rowspan="2">References</th></tr><tr><th>Technical parameters</th><th>Socio-economic parameters</th></tr></thead><tbody><tr><td>Mount Cameroon National Park Conservation</td><td>GIZ</td><td>GIZ (German Cooperation Agency)</td><td>Sustainable NWF production</td><td>Agroforestry with native species</td><td>NA</td><td>71,177</td><td>Unavailable</td><td>Adoption level: 14-22% participation within the targeted communities</td><td>(Awung and Marchant 2016)</td><td></td></tr><tr><td>"Un parisien, un arbre"</td><td>City of Paris</td><td>ONFI (French Company)</td><td>Sustainable wood fuel production; Sustainable wood and NWF production</td><td>Reforestation with native and exotic species</td><td>202.4</td><td>NA</td><td>Mortality rate: 15%</td><td>Unavailable</td><td>(Njoukam et al. 2013)</td><td></td></tr><tr><td>Banah-Bapouh forest REDD+</td><td>AFD</td><td>National Participatory Development Program (Cameroonian Public Program)</td><td>Sustainable forest management and carbon storage</td><td>Reforestation with native and exotic species</td><td>NA</td><td>NA</td><td>NA</td><td></td><td>(Gagou-Kakeu et al. 2020)</td><td></td></tr><tr><td>Study of spontaneous local Practices</td><td>NA</td><td>Local people</td><td>Increase of cocoa tree shade; Diversification and/or increase of rural incomes</td><td>Agroforestry with native species (cocoa fields)</td><td>NA</td><td>NA</td><td>Density: 102.7 to 274.4 stems/ha with a mean of 109.9 stems/ha</td><td>Economics: 450 to 1,700 USD/year for farms producing cocoa and fruits in the same plot</td><td>(Alemagi et al. 2015; Es-souma et al. 2020; Fole-fack and Darr 2021; Jagoret et al. 2009, 2014)</td><td></td></tr></tbody></table>
<table><caption>**Table 1 (continued)**</caption><thead><tr><th rowspan="2">Country</th><th rowspan="2">Name</th><th rowspan="2">Donor(s)</th><th rowspan="2">Implementer(s)</th><th rowspan="2">Stated objective(s) of the project</th><th rowspan="2">Forest restoration method promoted</th><th rowspan="2">Plantation results published Area (ha)</th><th rowspan="2">Number of trees</th><th colspan="2">Monitoring</th><th rowspan="2">References</th></tr><tr><th>Technical parameters</th><th>Socio-economic parameters</th></tr></thead><tbody><tr><td></td><td>CED-Led PES Scheme</td><td>UK</td><td>Center for Environment and Development (Cameroonian NGO)</td><td>Sustainable forest management and carbon storage</td><td>Reforestation with native and exotic species</td><td>NA</td><td>NA</td><td>NA</td><td>NA</td><td>(Gagou-Kakeu et al. 2020)</td></tr><tr><td></td><td>IUCN pro-poor REDD+Pilote</td><td>DAN-IDA; CBPF</td><td>International Union for the Conservation of Nature (International Institution)</td><td>Sustainable forest management and carbon storage</td><td>Assisted natural regeneration</td><td>NA</td><td>NA</td><td>NA</td><td>NA</td><td>(Gagou-Kakeu et al. 2020)</td></tr><tr><td></td><td>Pallisco-CIFM reforestation</td><td>Pallisco-CIFM</td><td>Pallisco-CIFM (French and Cameroonian Company)</td><td>Sustainable wood and NWFP production</td><td>Reforestation with native species (Baillonela toxisperma)</td><td>NA</td><td>450</td><td>Maintenance rate: 9% of distributed plants<br>Mortality rate: 84%</td><td>NA</td><td>(Semereab 2006)</td></tr><tr><td></td><td>Study of spontaneous local Practices</td><td>NA</td><td>Local people</td><td>Restoration of soil fertility; Sustainable wood and NWFP production</td><td>Assisted natural regeneration</td><td>NA</td><td></td><td>Density: 8 to 30 stems/ha to 600 to 800 stems/ha depending on the area</td><td>Adoption level: 67-100% of respondents practised ANR depending on the area<br>Economics: an average benefit of 555.32 USD/year</td><td>(Carriere 2002; Fon-doun and Tiki Manga 2000; Ro-biglio et al. 2012)</td></tr></tbody></table>
<figure><img src="image_14.png" /><figcaption>Table 1 (continued)</figcaption></figure>

<table><thead><tr><th rowspan="2">Country</th><th rowspan="2">Name</th><th rowspan="2">Donor(s)</th><th rowspan="2">Implementer(s)</th><th rowspan="2">Stated objective(s) of the project</th><th rowspan="2">Forest restoration method promoted</th><th rowspan="2">Plantation results published Area (ha)</th><th rowspan="2">Number of trees</th><th colspan="2">Monitoring</th><th rowspan="2">References</th></tr><tr><th>Productivity: 5 to 10 kg of Arabic gum/ ha/an</th><th>Socio-economic parameters</th></tr></thead><tbody><tr><td rowspan="2">DPGT and ESA</td><td rowspan="2">Private funds</td><td rowspan="2">SODECOTON (Cameroonian Company)</td><td>Sustainable NWFP production;</td><td>Reforestation with native species;</td><td rowspan="2">750 (reforestation)</td><td rowspan="2">NA</td><td rowspan="2">Productivity: 5 to 10 kg of Arabic gum/ ha/an</td><td rowspan="2">Economics: 0.57 to 8.18 USD/ha/year</td><td rowspan="2">(Palou Madi et al. 2010)</td></tr><tr><td>Restoration of soil fertility;</td><td>Assisted natural regeneration</td></tr><tr><td rowspan="2">Cameroon and Gabon</td><td rowspan="2">DACEFI</td><td rowspan="2">EU</td><td>Diversification and/or increase of rural incomes</td><td>Restoration and/or increase of rural incomes</td><td rowspan="2">10</td><td rowspan="2">NA</td><td rowspan="2">NA</td><td rowspan="2">NA</td><td rowspan="2">(Meunier et al. 2013; Sonne and Kana 2012)</td></tr><tr><td>Sustainable wood and NWFP production</td><td>Agroforestry with native species</td></tr><tr><td></td><td></td><td></td><td>WWF, WWF Gabon, WWF Cameroon, Nature+</td><td>International, Gabonese, Cameroonian and Belgian NGOs) and Gembloux</td><td></td><td></td><td></td><td></td><td></td></tr><tr><td></td><td></td><td></td><td>AgroBio Tech (Belgian Research Centre)</td><td></td><td></td><td></td><td></td><td></td><td></td></tr></tbody></table>
<table><caption>**Table 1 (continued)**</caption><thead><tr><th rowspan="2">Country</th><th rowspan="2">Name</th><th rowspan="2">Donor(s)</th><th rowspan="2">Implementer(s)</th><th rowspan="2">Stated objective(s) of the project</th><th rowspan="2">Forest restoration method promoted</th><th rowspan="2">Plantation results published Area (ha)</th><th rowspan="2">Number of trees</th><th colspan="2">Monitoring</th><th rowspan="2">References</th></tr><tr><th>Technical parameters</th><th>Socio-economic parameters</th></tr></thead><tbody><tr><td>CAR</td><td>PDRSO</td><td>AFD and FFEM</td><td>FRMi, TEREA, ONFI (French companies) and CIRAD (French Research Centre)</td><td>Sustainable wood fuel production; Deceleration of forest degradation processes; Diversification and/or increase of rural incomes</td><td>Agroforestry with <i>Acacia spp.</i>; Assisted natural regeneration</td><td>60 (agroforestry) (ANR)</td><td>1,668</td><td>NA</td><td>NA</td><td>(Kpolita et al. 2022; Sylvatrop & SalvaTerra 2021)</td></tr></tbody></table>
<figure><img src="image_15.png" /><figcaption>**Fig. 4** Classification of the local populations’ involvement in forest restoration initiatives in Central Africa (adapted from Bakker et al. (2020) and Arnstein (1969)</figcaption></figure>

North Kivu (5,476 ha, 21%) where the use of exotic species (mostly *Eucalyptus* spp. and *Grevilla* spp.) dominated (Bouyer et al. 2013; Lejeune et al., 2013). Reforestation with native species represented less than 1% of the total (23 ha) (Botulu et al. 2023; Péroches et al. 2019). Finally, some initiatives only reported the number of planted trees (Table 2), mainly through agroforestry and using native species in Cameroon (54%) or a mix of native and exotic species in the DRC (45%).

## Monitoring

Only 11 initiatives commented on the monitoring of planted trees, and 13 initiatives on the socio-economic parameters. The criteria used were diverse and hard to compare. Monitoring information included: productivity (6 initiatives), plantation densities (5), mortality rates (3), maintenance rate (3) and growth rates (2). Economic return is the only socio-economic parameter that is usually monitored, but at various scales (tree or field – 4 initiatives; household – 3; value chain – 1) (Table 1). The adoption level of forest or agroforest plantations (or the number of smallholders practicing the technique promoted) was evaluated in seven initiatives.

## Involvement of the Local Populations

When ranking the 26 initiatives according to the support strategy and the technical options offered, it appears that most initiatives had significant planting objectives and favored a high level of intervention (plant distribution, mechanical tillage, etc.) over a high level of empowerment of participants (Fig. 4). In this case, cooperation with the local population is symbolic, according to Arnstein’s (1969) typology of participation.

In this vein, only a few articles or reports mentioned a process to obtain the prior consent of participants, as well as land arrangements or a benefit-sharing plan to

<figure><img src="image_16.png" /></figure>
ensure the sustainability of the initiative. Four initiatives supported the creation of a
simple management plan and included these three parameters (Gagou-Kakeu et al.
2020; Meunier et al. 2013; Péroches et al. 2019; Sonne and Kana 2012). Five other
initiatives supported existing or new associations or farmers groups, with the objec-
tive of managing benefit sharing and access to land (Awung and Marchant 2016;
Bisiaux et al. 2009; Lejeune et al., 2013; Njoukam et al. 2013; Sabin et al. 2019).

Discussion

In this study, we aimed to (i) contextualize, (ii) characterize technical approaches
and (iii) analyze project strategies of local populations participation in forest resto-
ration initiatives in Central Africa. First, we found 26 initiatives mainly supported
by international cooperation funds and implemented by international NGOs and
Research Centers and located in four “restoration hot spots”: (i) the Grassfields area
in Cameroon, (ii) the dense forest area of Cameroon, (iii) the periphery of Kinshasa
in DRC and (iv) the Great Lakes region straddling the South and North-Kivu in DRC
and Rwanda. However, as the systematic review process is often thought to exclude
large amounts of information that have gone unpublished in peer-reviewed journals
(Greenhalgh et al. 2018), more initiatives (notably public and spontaneous local prac-
tices or recent initiatives) have likely been undertaken but have never been described
in the scientific literature. Two illustrative cases are (i) the extensive teak plantations
in the Central African Republic (CAR) and (ii) the World Bank (WB) and Central
African Forest Initiative (CAFI) restoration programs. Teak plantations in CAR were
initially established and maintained by the forest administration and are now managed
independently by the local populations. However, there is a notable lack of informa-
tion about these plantations beyond what can be gleaned from field observations and
common knowledge. WB and CAFI programs implemented by local NGOs are also
poorly documented (Péroches, *pers. com*.). Additional research would be needed to
improve the recognition of forest restoration, more particularly spontaneous prac-
tices of local populations in Central Africa, and to elucidate the factors impeding
their identification. Second, our results show that agroforestry is the most promoted
technic, often with exotic species, as *Acacia spp.*, and that all types of initiatives of
forest restoration are globally poorly monitored. Finally, and more importantly, we
demonstrate that cooperation with local populations is often symbolic.

Concentration of Initiatives in a Limited Geographical Area

The 26 forest restoration initiatives identified in this systematic review did not fully
represent the diversity of forest types (Réjou-Méchain et al. 2021) and socio-ecosys-
tems (Marien and Bassaler 2013) found in Central Africa. The vast majority of our
case studies were located in four areas in Cameroon and the DRC, confirming the
findings of larger studies (Martin et al. 2021; Ota et al. 2017) and the forest transi-
tion theory, which states that forest plantations are more likely to develop in highly
degraded areas (Mather 1992). Among these four areas, there are three historically
degraded areas: the Grassfields of Cameroon (Temgoua et al. 2011), the Great Lakes
region and the periphery of Kinshasa (Gond et al. 2016; Vancutsem et al. 2021). The fourth area (Center, South and East Cameroon) has been under increasing pressure since 2010 (Vancutsem et al. 2021).

## Poor Monitoring that Hampers long-term Support

Overall, forest restoration initiative monitoring in Central Africa is weak, because of the short duration of interventions (rarely more than five years) and the absence of implementation of a common framework, such as the AFR100 monitoring principles (AFR100, 2023), to evaluate the results of these reforestation initiatives based on their technical and socio-economic dimensions.

Even though information on the planted areas, the surviving and growth rates, the carbon storage, or the added value produced by planters are quantified in some documents, the lack of complete and homogeneous data complicates the evaluation of restoration strategies and success. This limitation is not specific to the region and was previously identified as a global priority by Gnacadja and Vidal (2022), Holl and Brancalion (2020, 2022) and Martin et al. (2021). The criteria presented here could form the basis of a more standardised framework (see Table 1; Fig. 4) complementary to the AFR100 principles (AFR100, 2023).

## Partnering with Local Populations

Although some spontaneous local initiatives were included in our analysis (Carrière, 2002; Jagoret et al. 2009; Temgoua et al. 2011), our results showed that external initiatives were predominant and that strategies were mostly based on high intervention levels and less on empowering farmers to sustainable tree planting (Fig. 4). The majority of initiatives structured their actions around entrusting local populations with the task of planting rather than fostering partnerships. For example, several initiatives pay beneficiaries to produce plants in nurseries for themselves or to prepare their own fields (Bouyer et al. 2013; GIZ 2020a; Sylvatrop & SalvaTerra 2021). This practice can achieve rapid tree planting but is not usually associated with the continuation and reproduction of the system (Sylvatrop & SalvaTerra 2021), except if payments and mutual commitment are made over time (Wunder 2007) which is not the case in the initiatives reviewed here. The quick and ambitious results awaited by international donors to justify their contribution largely explain these strategic choices. Nevertheless, it has been demonstrated that forest restoration efficiency is improved when there is a reliable partnership with farmers which prioritises their preferences (Shyamsundar et al. 2022; Jha et al. 2021; Seghieri et al. 2021). Such a partnership usually requires several preconditions. Firstly, the trajectories and interests of smallholders should be deeply analysed and made explicit (Herbohn et al. 2023; Mansourian et al. 2022; Ota et al. 2020). If we assume that, in the future, farmers will be planters and the fact that existing spontaneous initiatives are not described, we suggest the creation of a systematic approach to characterise smallholder farming systems and restoration practices in their context, similar to agrarian diagnosis. This multidisciplinary method requires an in-depth study of the landscape conditions, land management, natural resources using rights, existing markets, existing breeding and
cropping systems and dynamics of farming systems in this context (including the
allocation of production factors: capital, labour force and land) (Cochet 2015). This
method can be combined with others, such as participatory landscape analysis or
interactive cartography, which have already been tested in the DRC (Dubiez et al.
2013; Larzillière et al. 2013). Secondly, the prior consent of beneficiaries regarding
the technical and institutional characteristics of a forest restoration initiative should
be systematically obtained on a collective and individual basis. The Free, prior and
informed consent (FPIC) is still too often a formal procedure applied on a collective
scale when in reality it concerns individual practices. Thirdly, trade-offs between
local stakeholders and project managers should be analysed, discussed and agreed
upon. This is likely to involve a revision of the objectives of donors and project
managers to better accommodate the legitimate objectives of local stakeholders.
Fourthly, once consent has been obtained, it will be necessary to clarify and con-
tractually establish both the land and use rights arrangements between the parties
and the sharing of the goods, services and benefits expected from the restoration.
Finally, building and sustaining partnerships requires supportive local leadership and
encouragement from government authorities. These factors are rarely present prior to
intervention and take a long time to develop. Unfortunately, the current short dura-
tion of forest restoration initiatives does not allow for the development of this secure
framework for local populations.

Simple tree-planting or Forest Restoration??

Most of the initiatives identified in Central Africa focus primarily on the production
of tree products and economic objectives for smallholders, rather than on restor-
ing a native forest ecosystem. In fact, agroforestry with exotic species was the most
promoted technic, and the main expected benefits were sustainable wood fuel pro-
duction, positive impacts on soils and the diversification or enhancement of rural
incomes. In particular, exotic species are chosen because their seeds are readily avail-
able, they grow quickly, they are productive (even on degraded soils) and, in the case
of *Acacia spp.*, they fix atmospheric nitrogen (Bisiaux et al. 2009; Bouyer et al. 2013;
Proces et al. 2017).

A productive or economic objective seems necessary to motivate smallholders to
restore the native forest on their land. In the rural complex earlier described, the refor-
estation initiatives undertaken by smallholders do not necessarily target the recovery
of the initial forest ecosystem because the primary objective of these planters is to
produce wood and food products for their own consumption or to get incomes for
their household. These local actions could be complemented by more ambitious res-
toration strategies/initiatives undertaken by other actors (public or private) targeting
environmental objectives at a large scale in areas where the land tenure has been
secured.
**Conclusion**

In Central Africa, forest restoration by farmers was predominantly conducted in degraded areas in Cameroon and the DRC. Initiatives were focused on productive and economic purposes (notably wood fuel production and diversification of small-holders’ incomes). The areas that were reported as restored predominantly exhibited management practices involving agroforestry and forest plantations featuring exotic species, such as *Acacia spp.* and *Eucalyptus spp.* Notably, we identified geographic variation between the dense forest area of Cameroon, the periphery of Kinshasa, the Great Lakes region, and the Grassfields area. The majority of the initiatives were based on a high level of intervention rather than the empowerment of planters for sustainable tree planting. Furthermore, there was little information regarding monitoring, which prevented the evaluation of the various options based on their environmental or socio-economic dimensions.

Developing true partnerships with local populations appears to be the main challenge for those supporting forest restoration initiatives in Central Africa. This would require in-depth exchanges with local authorities and farmers, together with a comprehensive analysis of their territories and farming systems, as well as the establishment of clear contracts clarifying the roles of these two stakeholders in securing land tenure, tree ownership and the expected sharing of goods, services and benefits to be derived from these reforestation initiatives.

**Supplementary Information** The online version contains supplementary material available at https://doi.org/10.1007/s11842-025-09586-6.

**Acknowledgements** Principal funding was provided by the French Fund for World Environment (FFEM - grant number CZZ 2123.01). The PhD thesis of Adrien Péroches is funded by the National Agency for Technologic Research (ANRT) under grant number CIFRE 2021/1614. The authors would like to thank Jean-Marie Paillat and Michel Vaillant from ISTOM, Régis Peltier from CIRAD, and Coretin Lucas and Hugo Lehoux from Asc for their relevant remarks during the writing process. In addition, Adrien Péroches thanks Clarisse Vautrin from CIRAD for her support in mapping and Sophie Connolly for the English editing.

**Author Contributions** All authors contributed to the study's conception and design. The conceptualisation and methodology were proposed by Adrien Péroches and validated by each co-author. The literature search was performed by Adrien Péroches and read by Adrien Péroches (all articles) and all co-authors (a sample excepted Marc Oswald). The statistical analyses were carried out by Adrien Péroches and Adeline Fayolle. The first draft of the manuscript was written by Adrien Péroches and all co-authors commented on previous versions of the manuscript. All co-authors read and approved the final manuscript. FFEM funding acquisition and management were undertaken by Guillaume Lescuyer and Emilien Dubiez.

**Funding** Open access funding provided by CIRAD.

**Declarations**

**Conflict of interest** The authors declare no conflict of interest.

**Open Access** This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this
article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.

## References

Achard F, DeFries R, Eva H, Hansen M, Mayaux P, Stibig H-J (2007) Pan-tropical monitoring of deforestation. Environ Res Lett 2(4):045022. https://doi.org/10.1088/1748-9326/2/4/045022

AFR100 (2023) Guiding principles for measuring and monitoring progress on forest and landscape restoration in Africa (Working Paper Series, p 11). AFR100. https://afr100.org/sites/default/files/2023-07/Monitoring%20Progress_English_Draft.pdf

Alemagi D, Duguma L, Minang PA, Nkeumoe F, Feudjio M. Tchoundjeu Z (2015) Intensification of cocoa agroforestry systems as a REDD+strategy in Cameroon: hurdles, motivations, and challenges. Int J Agric Sustain 13(3):187-203. https://doi.org/10.1080/14735903.2014.940705

Arnstein SR (1969) A ladder of citizen participation. J Am Inst Plan 35(4):216-224

Asaah EK, Tchoundjeu Z, Leakey RRB, Takousting B, Njong J, Edang I (2011) Trees, agroforestry and multifunctional agriculture in Cameroon. Int J Agric Sustain 9(1):110-119. https://doi.org/10.3763/ijas.2010.0553

Awazi NP, Tchamba MN, Temgoua LF (2020) Climate-smart practices of smallholder farmers in Cameroon confronted with climate variability and change: the example of agroforestry. Agric Res 10(1):83-96. https://doi.org/10.1007/s40003-020-00477-0

Awazi NP, Tchamba MN, Temgoua LF, Tientcheu-Avana M-L (2021) Agroforestry as an adaptation option to climate change in Cameroon: assessing farmers' preferences. Agric Res 11(2):309-320. https://doi.org/10.1007/s40003-021-00562-y

Awung N, Marchant R (2016) Investigating the role of the local community as co-managers of the Mount Cameroon National park conservation project. Environments 3(4):36. https://doi.org/10.3390/environments3040036

Bakker T, Blundo Canto G, Dugué P, de Tourdonnet S (2020) To what extent is the diversity of farmer field schools reflected in their assessment? A literature review. J Agric Educ Ext 27(3):381-401. https://doi.org/10.1080/1389224X.2020.1858890

Bandi MM, Mahimba MB, Minengu JdeD, Khasa DP, Mbe-Mpie PM (2020) Opportunités et défis de l'agroforesterie dans et en périphérie de la Réserve de Biosphère de Luki au Kongo central en République Démocratique du Congo.

Bandi MM, Mahimba MB, Mpie M, M'vubu PM, A. R. N., Khasa DP (2022) Adoption of agroforestry practices in and around the Luki biosphere reserve in the Democratic Republic of the Congo. Sustainability 14(16):9841. https://doi.org/10.3390/su14169841

Bastin J-F, Finegold Y, Garcia C, Mollicone D, Rezende M, Routh D, Zohner CM, Crowther TW (2019) The global tree restoration potential. Science 365(6448):76-79. https://doi.org/10.1126/science.aax0848

Besseau P, Graham S, Christophersen T (2018) Restauration des paysages forestiers: La Clé D'un avenir durable. Partenariat mondial pour la restauration des paysages forestiers, p 45

Bisiaux F, Peltier R, Muliele J-C (2009) Plantations industrielles et agroforesterie Au service des populations des plateaux Batéké, Mampu, En république démocratique du congo. BOIS FORETS DES TROPIQUES 301(301):21. https://doi.org/10.19182/bft2009.301.a20404

Borrini-Feyarabend grazia, Farvar T, Nguinguiri M, J.-C., Ndangang A, V (2000) La gestion des ressources naturelles—organisation, négociations et apprentissage par l'action (GTZ&UICN)

Botulu R, Bisimwa benjamin, Omba J-C, Dubiez E, Lescuyer G (2023) Suivi et analyse de la gestion des plantations villageoises effectuées en saison A 2022 dans le cadre de la restauration forestière, composante 2 du projet PROFEAAC, dans les Groupement Yangandi et Totuku (p 30). Projet PROFEAAC

Bouyer O, Maurice J, Le Crom M, Rutinigira L (2013) Evaluation finale du projet EcoMakala—viabilisation durable de l'approvisionnement en boisénergie des populations rurales riveraines de la ville de Goma (République Démocratique du Congo) (p 140). SalvaTerra
Bucagu C, Vanlauwe B, Van Wijk MT, Giller KE (2013) Assessing farmers’ interest in agroforestry in two contrasting agro-ecological zones of Rwanda. Agrofor Syst 87(1):141–158. https://doi.org/10.1007/s10457-012-9531-7

Buttoud G, Nguinguiri J-C, Aubert S, Bakouma J, Karsenty A, Buttoud K, I., Lescuyer G (2016) La gestion inclusive des forêts d’afrique centrale—Passer de La participation Au partage des pouvoirs. CIFOR & FAO

Carriere S (2002) L’abattage sélectif: Une pratique agricole ancestrale Au service de La régénération For-estière. Bois Et Forêts Des Tropiques 272(2):45–62. https://doi.org/10.19182/bft2002.272.a20154

Chazdon R (2008) Beyond deforestation: restoring forests and ecosystem services on degraded lands. Science 320(5882):1458–1460. https://doi.org/10.1126/science.1155365

Chazdon R, Brancalion P (2019) Restoring forests as a means to many ends. Science 365(6448):24–25. https://doi.org/10.1126/science.aax9539

Chazdon RL, Brancalion PHS, Lamb D, Laestadius L, Calmon M, Kumar C (2017) A policy-driven knowledge agenda for global forest and landscape restoration. Conserv Lett 10(1):125–132. https://doi.org/10.1111/conl.12220

Cochet H (2015) Comparative agriculture. Springer/Quae

Curtis PG, Slay CM, Harris NL, Tyukavina A, Hansen MC (2018) Classifying drivers of global forest loss. Science 361(6407):1108–1111. https://doi.org/10.1126/science.aau3445

d’Aquino P, Seck SM (2001) Et Si les approches participatives étaient inadaptées à la gestion décentralisée de territoire?/and if participative approaches were inadapted to decentralised territorial management? Géocarrefour 76(3):233–239. https://doi.org/10.3406/geoca.2001.2561

Dalimier J, Achard F, Delhez B, Desclée B, Bourgoin C, Eva H, Gourlet-Fleury S, Hansen MC, Kibambe J-P, Mortier F, Ploton P, Réjou-Méchain M, Vancutsem C, Jungers Q, Defourny P (2022) Répartition des types de forêts et évolution selon leur affectation. In: Les forêts d’Afrique centrale—Etat des forêts 2021. CIFOR, p 459

Degrande A, Tadjo P, Takoutsing B, Asaah E, Tsobeng A, Tchoundjeu Z (2012) Getting trees into farmers’ fields: success of rural nurseries in distributing high quality planting material in Cameroon. Small-Scale For 12(3):403–420. https://doi.org/10.1007/s11842-012-9220-4

Dkamela GP (2012) Essai de reconstitution du cadre D’action et des opportunités En Matière D’agroforesterie En république démocratique du congo: perspectives pour Une politique publique. World Agroforestry Centre, p 154

Dubiez E, Vermeulen C, Tonneau J-P, Yamba Y, Mvolo T, B., Larzillière A (2013) Le paysage comme outil d’aménagement des terroirs villageois. BOIS FORETS DES TROPIQUES 315(315):11. https://doi.org/10.19182/bft2013.315.a20534

Dubiez E, Freycon V, Marien J-N, Peltier R, Harmand J-M (2018) Long term impact of *Acacia auriculiformis* woodlots growing in rotation with cassava and maize on the carbon and nutrient contents of Savannah sandy soils in the humid tropics (Democratic Republic of Congo). Agroforest Syst 93(3):1167–1178. https://doi.org/10.1007/s10457-018-0222-x

Essouma FM, Michel I, Mala WA, Levang P, Ambang Z, Begoude Boyogueno AD, Moisy C, Ngono F, Carriere SM (2020) Cocoa-based agroforestry system dynamics and trends in the Akongo subregion of central Cameroon. Agrofor Syst 95(5):843–854. https://doi.org/10.1007/s10457-020-00510-9

Fagan ME, Kim D-H, Settle W, Ferry L, Drew J, Carlson H, Slaughter J, Schaferbien J, Tyukavina A, Harris NL, Goldman E, Ordway EM (2022) The expansion of tree plantations across tropical biomes. Nat Sustain 5(8):681–688. https://doi.org/10.1038/s41893-022-00904-w

FAO (2020) Global forest resources assessment 2020: main report. FAO. https://doi.org/10.4060/ca9825en

Folefack AJJ, Darr D (2021) Promoting cocoa agroforestry under conditions of separated ownership of land and trees: strengthening customary tenure institutions in Cameroon. Land Use Policy 108:105524. https://doi.org/10.1016/j.landusepol.2021.105524

Fondoun JM, Tiki Manga T (2000) Farmers Indigenous practices for conserving *Garcinia kola* and *Gnetum africanum* in Southern Cameroon. Agrofor Syst 48:289–302

Fonteyn D, Vermeulen C, Gorel A, Silva de Miranda PL, Lhoest S, Fayolle A (2023) Biogeography of central African forests: determinants, ongoing threats and conservation priorities of mammal assemblages. Divers Distrib 29(6):698–712. https://doi.org/10.1111/ddi.13677

Foundjem-Tita D, Tchoundjeu Z, Speelman S, D’Haese M, Degrande A, Asaah E, Van Huylenbroeck G, Van Damme P, Ndoye O (2013) Policy and legal frameworks governing trees: incentives or disincentives for smallholder tree planting decisions in Cameroon? Small-Scale For 12(3):489–505. https://doi.org/10.1007/s11842-012-9225-z
Gagou-Kakeu J, Di Gregorio M, Paavola J, Sonwa DJ (2020) REDD+policy implementation and institu-
tional interplay: evidence from three pilot projects in Cameroon. Center for International. https://doi
.org/10.17528/cifor/007882. Forestry Research (CIFOR)

Gann GD, McDonald T, Walder B, Aronson J, Nelson CR, Jonson J, Hallett JG, Eisenberg C, Guariguata MR, Liu J, Hua F, Echeverría C, Gonzales E, Shaw N, Decleer K, Dixon KW (2019) International principles and standards for the practice of ecological restoration, second edition. Restor Ecol. https://doi.org/10.1111/rec.13035

Gillet P, Vermeulen C, Feintrenie L, Dessard H, Garcia C (2016) Quelles sont les causes de la déforestation dans le bassin du Congo? Synthèse bibliographique et études de cas. BASE. https://doi.org/10.2551 8/1780-4507.13022

GIZ (2013) Développement D'un modèle de gestion sylvicole et de suivi-évaluation des plantations dans le cadre des activités de (re)boisement Au Sud-Kivu. GIZ, p 86

GIZ (2020a) Programme de maintien de La biodiversité et de gestion durable des forêts (BGF) En répub-
lique démocratique du congo (RDC)—Champ D'action « introduction D'une gestion durable des
forêts Dans les provinces du Sud-Kivu et du Maniema—Rapport final. GIZ, p 30

GIZ (2020b) Programme de maintien de La biodiversité et gestion durable des forêts (BGF) Province du Sud Kivu, RDC. GIZ, p 8

Gnacadja L, Vidal A (2022) How can science help to implement the UN decade on ecosystem restoration 2021–2030? Philos Trans R Soc B Biol Sci 378(1867):20210066. https://doi.org/10.1098/rstb.2021.0066

Gond V, Dubiez E, Boulogne M, Gigaud M, Péroches A, Pennec A, Fauvet N, Peltier R (2016) Dynamic of forest cover and carbon stock change in the Democratic Republic of congo: case of wood-fuel supply basin for Kinshasa. Bois et Forêts Des Tropiques 327(1):19–28

Greenhalgh T, Thorne S, Malterud K (2018) Time to challenge the spurious hierarchy of systematic over narrative reviews? Eur J Clin Invest 48:1–6. https://doi.org/10.1111/eci.12931

Guizol P, Diakhite M, Seka J, Bring C, Mbonayem L, Awono A, Oyono P-R, Mokpidie D, Ndikumagenge C, Sonwa DJ (2022) La restauration des paysages forestiers (RPF) En afrique centrale. Les forêts d’afrique centrale—Etat des forêts 2021. CIFOR

Gyau A, Chiatoh M, Franzel S, Asaah E, Donovan J (2012) Determinants of farmers’ tree planting behav-
iour in the North West region of Cameroon: the case of *Prunus africana*. Int For Rev 14(3):265–274.
https://doi.org/10.1505/146554812802646620

Hansen MC, Potapov PV, Moore R, Hancher M, Turubanova SA, Tyukavina A, Thau D, Stehman SV, Goetz SJ, Loveland TR, Kommareddy A, Egorov A, Chini L, Justice CO, Townshend JRG (2013) High-resolution global maps of 21st-century forest cover change. Science 342(6160):850–853.
https://doi.org/10.1126/science.1244693

Harris NL, Gibbs DA, Baccini A, Birdsey RA, De Bruin S, Farina M, Fatoyinbo L, Hansen MC, Herold M, Houghton RA, Potapov PV, Suarez DR, Roman-Cuesta RM, Saatchi SS, Slay CM, Turubanova SA, Tyukavina A (2021) Global maps of twenty-first century forest carbon fluxes. Nat Clim Change 11(3):234–240. https://doi.org/10.1038/s41558-020-00976-6

Herbohn J, Ota L, Gregorio N, Chazdon R, Fisher R, Baynes J, Applegate G, Page T, Carias D, Romero C, Putz FE, Firn J (2023) The community capacity curve applied to reforestation: a framework to support success. Philos Trans R Soc B Biol Sci 378(1867):20210079. https://doi.org/10.1098/rstb.2021.0079

Holl KD, Brancalion PHS (2020) Tree planting is not a simple solution. Science 368(6491):580–581.
https://doi.org/10.1126/science.aba8232

Holl KD, Brancalion PHS (2022) Which of the plethora of tree-growing projects to support? One Earth 5(5):452–455. https://doi.org/10.1016/j.oneear.2022.04.001

Iiyama M, Mukuralinda A, Ndayambaje JD, Musana BS, Ndoli A, Mowo JG, Garrity D, Ling S, Ruganzu V (2018a) Addressing the paradox—the divergence between smallholders’ preference and actual adoption of agricultural innovations. Int J Agric Sustain 16(6):472–485. https://doi.org/10.1080/147 35903.2018.1539384

Iiyama M, Mukuralinda A, Ndayambaje J, Musana B, Ndoli A, Mowo J, Garrity D, Ling S, Ruganzu V (2018b) Tree-based ecosystem approaches (TBEAs) as multi-functional land management strate- gies—evidence from Rwanda. Sustainability 10(5):1360. https://doi.org/10.3390/su10051360

Jagoret P, Ngogue HT, Bouambi E, Battini J-L, Nyassé S (2009) Diversification des exploitations agri-
coles à base de cacaoyer au centre Cameroun: Mythe ou réalité? Biotechnol Agron Soc Environ
13(2):271–280
Jagoret P, Kwesseu J, Messie CA, Michel I, Malézieux É (2014) Valeurs d'usage des ligneux utilisés en agroforesterie: Les cacaoyères du Centre-Cameroun. BOIS FORETS DES TROPIQUES 321(321):45. https://doi.org/10.19182/bft2014.321.a31217

Jha S, Kaechele H, Sieber S (2021) Factors influencing the adoption of agroforestry by smallholder farmer households in Tanzania: case studies from Morogoro and Dodoma. Land Use Policy 103:105308. https://doi.org/10.1016/j.landusepol.2021.105308

Kachaka ÉY, Munson AD, Gélinas N, Khasa D (2020) Adoption of an improved fallow practice using *Acacia auriculiformis* on the Batéké plateau in the Democratic Republic of the Congo. Agroforest Syst 94(3):1047–1058. https://doi.org/10.1007/s10457-019-00474-5

Karsenty A, Asseme S (2010) Renforcement des capacités institutionnelles Liées à La réduction des émissions dues à La dégradation et à La déforestation (REDD) En vue d'une gestion durable des forêts du Bassin du Congo—Diagnostics des systèmes de gestion Foncière. COMIFAC, p 32

Kimengsi JN, Ngu DN (2022) Community participation and forest management dynamics in rural Cameroon. World Dev Perspect 27:100442. https://doi.org/10.1016/j.wdp.2022.100442

Kiyani P, Andoh J, Lee Y, Lee DK (2017) Benefits and challenges of agroforestry adoption: a case of Musebeya sector, Nyamagabe district in Southern Province of Rwanda. For Sci Technol 13(4):174–180. https://doi.org/10.1080/21580103.2017.1392367

Kpolita A, Dubiez E, Yongo O, Peltier R (2022) First evaluation of the use of assisted natural regeneration by central African farmers to restore their landscapes. Trees For People 7:100165. https://doi.org/10.1016/j.tfp.2021.100165

Larzillière A, Vermeulen C, Dubiez E, Yamba Yamba T, Diowo S, Mumbere G (2013) La maquette interactive, un outil novateur de participation. BOIS FORETS DES TROPIQUES 315(315):21. https://doi.org/10.19182/bft2013.315.a20535

lejeune G, Ansay F, Van Geit M, Lusenge T (2013) ECOmakala: répondre à la demande énergétique pour protéger les forêts du parc National des virunga au Nord-Kivu (RDC) et lutter Contre La Pauvreté. WWF, p 36

Lewis SL, Wheeler CE, Mitchard ETA, Koch A (2019) Regenerate natural forests to store carbon. Nat Comment 568:25–28. https://doi.org/10.1038/d41586-019-01026-8

Lhoest S (2020) Biodiversity and ecosystem services in tropical forests: the role of forest allocations in the Dja area, Cameroon. Université de Liège - Gembloux AgroBio Tech

Mansourian S, Kleymann H, Passardi V, Winter S, Derkyi MAA, Diederichsen A, Gabay M, Pacheco P, Vallauri D, Kull CA (2022) Governments commit to forest restoration, but what does it take to restore forests? Environ Conserv 49(4):206–214. https://doi.org/10.1017/S0376892922000340

Marien J-N, Bassaler N (2013) Éléments de prospective à L'horizon 2040 pour les écosystèmes forestiers d'afrique centrale. COMIFAC

Marshall AR, Waite CE, Pfeifer M, Banin LF, Rakotonarivo S, Chomba S, Herbohn J, Gilmour DA, Brown M, Chazdon RL (2022) Fifteen essential science advances needed for effective restoration of the world's forest landscapes. Philos Trans R Soc B Biol Sci 378(1867):20210065. https://doi.org/10.1098/rstb.2021.0065

Martin MP, Woodbury DJ, Doroski DA, Nagele E, Storace M, Cook-Patton SC, Pasternack R, Ashton MS (2021) People plant trees for utility more often than for biodiversity or carbon. Biol Conserv 261:109224. https://doi.org/10.1016/j.biocon.2021.109224

Mather AS (1992) The forest transition. Area 24(4):367–379 Scopus

Mayaux P, Bartholomé E, Massart M, Vancutsem C, Cabral A, Nongierma A, Diallo O, Pretorius C, Thompson M, Cherlet M, Pekel J-F, Defourny P, Vasconcelos M, Di Gregorio A, Fritz S, De Gandi G, Elvidge C, Vogt P, Belward A (2003) A land cover map of Africa—Carte de l'occupation du Sol de L'Afrique. Office for Official Publications of the European Communities

Meunier Q, Vermeulen C, Federspiel M (2013) Projet 'Développement des Alternatives Communautaires à L'Exploitation Forestière Illégale' (Phase 2)—Rapport d'activité 2013 de la composante Gabon. Projet DACEFI, p 85

Moher D, Liberati A, Tetzlaff J, Altman DG (2010) Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement. Int J Surg 8(5):336–341. https://doi.org/10.1016/j.ijlsu.2010.02.007

Molenaar JW, Kessler JJ (2008) Manuel de formation Sur L'Agroforesterie Dans Le cadre de l'intensification agricole. IFDC, p 43

Mukuralinda A, Ndayambaje JD, Iiyama M, Ndoli A, Musana BS, Garrity D, Ling S (2016) Taking to scale tree-based systems in Rwanda to enhance food security, restore degraded land, improve resilience to climate change and sequester carbon. World Agroforestry Centre, p 52
Ndayambaje JD, Heijman WJM, Mohren GMJ (2012) Household determinants of tree planting on farms in rural Rwanda. Small-Scale For 11(4):477–508. https://doi.org/10.1007/s11842-012-9196-0

Ndayambaje JD, Heijman WJM, Mohren GMJ (2013) Farm woodlots in rural Rwanda: purposes and determinants. Agrofor Syst 87(4):797–814. https://doi.org/10.1007/s10457-013-9597-x

Njoukam R, Cuny P, Cornet J-G, Maurice J (2013) PROJET DE REBOISEMENT COMMUNAL UN PARISIEN, UN ARBRE AU CAMEROUN: UNE EXPÉRIENCE DE FORESTERIE PARTICIPATIVE. Revue Forestière Française 6:527. https://doi.org/10.4267/2042/53987

Nkamleu GB, Manyong VM (2005) Factors affecting the adoption of agroforestry practices by farmers in Cameroon. Small-Scale For Econ Manage Policy 4(2):135–148. https://doi.org/10.1007/s11842-00-5-0009-6

Noeldeke B, Winter E, Ntwauhiganayo EB (2022) Representing human decision-making in agent-based simulation models: agroforestry adoption in rural Rwanda. Ecol Econ 200:107529. https://doi.org/10.1016/j.ecolecon.2022.107529

Nsimundele Nkondo L, Diansambu Makanua I, Dubiez E, Proces P, Marien J-N, Peltier R, Vermeulen C (2010) Conserver ou manger la forêt? Le paradoxe des paysans en périphérie de Kinshasa, RDC. Le Flamboyant 66/67:33–37

ONFI & Novacel (2012) Étude de préfaisabilité Sur Les potentialités de développement des Filières agro-foresterie et bois-énergie Dans Le Bassin d’approvisionnement de Kinshasa. ONFI, p 127

Ota L, Herbohn J, Harrison S, Gregorio N, Engel VL (2017) Smallholder reforestation and livelihoods in the humid tropics: a systematic mapping study. Agroforest Syst 92(6):1597–1609. https://doi.org/10.1007/s10457-017-0107-4

Ota L, Herbohn J, Gregorio N, Harrison S (2020) Reforestation and smallholder livelihoods in the humid tropics. Land Use Policy 92:104455. https://doi.org/10.1016/j.landusepol.2019.104455

Palou Madi O, Peltier R, Balarabe O, Ntoupka M, Sibelet N (2010) Abandon Ou extension des plantations D’acacias Au Nord-Cameroun: Tout dépendra du fonctionnement des Filières Gomme arabique. BOIS FORETS DES TROPIQUES 306(3064):57. https://doi.org/10.19182/bft2010.306.a20432

Paul C, Fraser IM (2014) Woodfuel plantation projects in Kinshasa Province: potential contribution to the alleviation of pressure on natural forests. Int For Rev 16(6):507–523

Peltier R, Dubiez É, Diowo S, Gigaud M, Marien J-N, Marquant B, Peroches A, Proces P, Vermeulen C (2014) Assisted natural regeneration in slash-and-burn agriculture: results in the Democratic Republic of the Congo. BOIS FORETS DES TROPIQUES 321(321):67. https://doi.org/10.19182/bft2014.321.a31220

Péroches A, Dubiez E, Peltier R, Procès P, Diowo S, Yamba-Yamba T, Vermeulen C (2019) Les plans simples de gestion destinés à La production de bois-énergie En périphérie de Kinshasa: La participation et La restauration à l’épreuve du foncier. BOIS FORETS DES TROPIQUES 340. https://doi.org/10.19182/bft2019.340.a31698

Peroches A, Dubiez E, Fayolle A, Koutika L-S, Mapenzi N, Vermeulen C, Lescuyer G (2023) Forest restoration initiatives by local populations in central Africa—protocol for a systematic review. HAL hal-04206366:10

Poorter L, Bongers F, Aide TM, Almeyda Zambrano AM, Balvanera P, Becknell JM, Boukili V, Brancalion PHS, Broadbent EN, Chazdon RL, Craven D, De Almeida-Cortez JS, Cabral GAL, De Jong BHJ, Denslow JS, Dent DH, DeWalt SJ, Dupuy JM, Durán SM, Rozendaal DMA (2016) Biomass resilience of neotropical secondary forests. Nature 530(7589):211–214. https://doi.org/10.1038/nature16512

Poorter L, Craven D, Jakovac CC, Van Der Sande MT, Amissah L, Bongers F, Chazdon RL, Farrier CE, Kambach S, Meave JA, Muñoz R, Norden N, Rüger N, Van Breugel M, Zambrano A, Amani AM, Andrade B, Brancalion JL, Broadbent PHS, Hérault EN, B (2021) Multidimensional tropical forest recovery. Science 374(6573):1370–1376. https://doi.org/10.1126/science.abh3629

Proces P, Dubiez E, Bisiaux F, Péroches A, Fayolle A (2017) Production d'Acacia auriculiformis dans le système agroforestier de Mampu, plateau Batéké, République démocratique du Congo. BOIS FORETS DES TROPIQUES 334:23. https://doi.org/10.19182/bft2017.334.a31489

Réjou-Méchain M, Mortier F, Bastin J-F, Cornu G, Barbier N, Bayol N, Bénédet F, Bry X, Dauby G, Deblauwe V, Doucet J-L, Doumenge C, Fayolle A, Garcia C, Lubamba K, Loumeto J-P, Ngomanda J-J, Ploton A, Sonké P, Gourlet-Fleury B, S (2021) Unveiling African rainforest composition and vulnerability to global change. Nature 593(7857):90–94. https://doi.org/10.1038/s41586-021-03483-6

Reyniers C (2014) L'approche Interactionniste pour L'analyse D'un projet D'agroforesterie Villageoise Sur Le plateau des Batéké (République démocratique du Congo). VertigO 14(Num-ro 1). https://doi.org/10.4000/vertigo.14761
Reyniers C (2019) Agroforesterie et déforestation En république démocratique du congo. Miracle Ou
Mirage Environnemental? Mondes en développement 187(3):113–132. https://doi.org/10.3917/me
d.187.0113. n°

Reyniers C, Karsenty A, Vermeulen C (2015) Les paysans sans terre et REDD+ en RDC: les logiques locales face aux interventions internationales

Robiglio V, Lescuyer G, Cerutti PO (2012) From farmers to loggers: the role of shifting cultivation land- scapes in timber production in Cameroon. Small-Scale For 12(1):67–85. https://doi.org/10.1007/s1 1842-012-9205-3

Sabin S, Dieudon B, Mitchell J, White J, Chin C, Morikawa R (2019) Community-Based watershed change: a case study in Eastern congo. Forests 10(6):475. https://doi.org/10.3390/f10060475

Seghieri J, Droy I, Hadgu K, Place F (2021) Introduction to the special issue scaling up of agroforestry innovations: enhancing food, nutrition and income security. Agrofor Syst 95(7):1245–1249. https://d oi.org/10.1007/s10457-021-00689-5

Semereab E (2006) Etude de La dynamique des essences commerciales Au Sein des Jachères issues de l'agriculture itinérante Badjoué (Cameroun) (p. 96) [Mémoire de Fin d'Etudes]. Faculté Universita- ire des Sciences Agronomiques de Gembloux

Shapiro AC, Grantham HS, Aguilar-Amuchastegui N, Murray NJ, Gond V, Bonfils D, Rickenbach O (2021) Forest condition in the congo basin for the assessment of ecosystem conservation status. Ecol Ind 122:107268. https://doi.org/10.1016/j.ecolind.2020.107268

Shapiro A, d'Annunzio R, Desclée B, Jungers Q, Kondjo HK, Iyanga JM, Gangyo FI, Nana T, Obame CV, Milandou C, Rambaud P, Sonwa DJ, Mertens B, Tchana E, Khasa D, Bourgoin C, Ouissika CB, Kipute DD (2023) Small scale agriculture continues to drive deforestation and degradation in fragmented forests in the congo basin (2015–2020). Land Use Policy 134:106922. https://doi.org/10.1016/j.landusepol.2023.106922

Shyamsundar P, Cohen F, Boucher TM, Kroeger T, Erbaugh JT, Waterfield G, Clarke C, Cook-Patton SC, Garcia E, Juma K, Kaur S, Leisher C, Miller DC, Oester K, Saigal S, Siikamaki J, Sills EO, Thaung T, Trihadmojo B, Zhang XX (2022) Scaling smallholder tree cover restoration across the tropics. Glob Environ Change 76:102591. https://doi.org/10.1016/j.gloenvcha.2022.102591

Smith-Dumont E, Kuria A, Muthuri C, Kindt R, Sinclair F (2012) Manuel de terrain pour la sélection et la gestion des Arbres. World Agroforestry Center, p 74

Smith-Dumont E, Bonhomme S, Sinclair F (2015) Guide technique D'agroforesterie pour la sélection et la gestion des arbres au Nord-Kivu. World Agroforestry Centre, p 131

Smith-Dumont E, Bonhomme S, Pagella TF, Sinclair FL (2017) Structured stakeholders engagement leads to development of more diverse and inclusive agroforestry options. Exp Agric 55(S1):252–274. https://doi.org/10.1017/S0014479716000788

Sonne N, Kana R (2012) Rapport d'activité—Projet DACEFI - Composante Cameroun—Avril 2011 à Mars 2012. Projet 'Développement des Alternatives Communautaires à L'Exploitation Forestière Illégale' (Phase 2), p 22

Stainback GA, Masozera M, Mukuralinda A, Dwivedi P (2012) Smallholder agroforestry in Rwanda: a SWOT-AHP analysis. Small-Scale For 11(3):285–300. https://doi.org/10.1007/s11842-011-9184-9

Sylvatrop & SalvaTerra (2021) Evaluation finale du projet de Développement Régional du Sud-Ouest (PDRSO) de la République Centrafricaine. Projet PDRSO, p 93

Tassin J, Rangan H, Kull CA (2012) Hybrid improved tree fallows: harnessing invasive Woody legumes for agroforestry. Agrofor Syst 84(3):417–428. https://doi.org/10.1007/s10457-012-9493-9

Tchatchou B, Sonwa DJ, Ifo SA, Tiani A-M (2015) Deforestation and forest degradation in the congo basin: state of knowledge, current causes and perspectives. Center for International. https://doi.org/10.1528/cifor/005894. Forestry Research (CIFOR)

Tchoundjeu Z, Degrande A, Leakey RRB, Nimino G, Kemajou E, Asaah E, Facheux C, Mbile P, Mbosso C, Sado T, Tsobeng A (2010) Impacts of participatory tree domestication on farmer livelihoods in West and Central Africa. For Trees Livelihoods 19(3):217–234. https://doi.org/10.1080/14728028.2010.9752668

Tegegne YT, Lindner M, Fobissie K, Kanninen M (2016) Evolution of drivers of deforestation and forest degradation in the congo basin forests: exploring possible policy options to address forest loss. Land Use Policy 51:312–324. https://doi.org/10.1016/j.landusepol.2015.11.024

Temgoua L, Njoukam R, Peltier R (2011) Plantations ingénieuses de bois d'œuvre par les paysans de l'Ouest-Cameroun. Bois et Forêts Des Tropiques 309(3):63–76. https://doi.org/10.19182/bft2011.309.a20467
Tyukavina A, Hansen MC, Potapov P, Parker D, Okpa C, Stehman SV, Kommareddy I, Turubanova S (2018) Congo basin forest loss dominated by increasing smallholder clearing. Sci Adv 4(11):eaat2993.
https://doi.org/10.1126/sciadv.aat2993

UNEP (2022) Decision adopted by the conference of the parties to the convention on biological diversity—Kunming-Montreal Global Biodiversity Framework. United Nations, p 15. https://www.unep.org/resources/kunming-montreal-global-biodiversity-framework

Vancutsem C, Achard F, Pekel J-F, Vieilledent G, Carboni S, Simonetti D, Gallego J, Aragão LEOC, Nasi R (2021) Long-term (1990–2019) monitoring of forest cover changes in the humid tropics. Sci Adv 7(10):eabe1603. https://doi.org/10.1126/sciadv.abe1603

Vermeulen C, Dubiez É, Proces P, Mukumary SD, Yamba TY, Mutambwe S, Peltier R, Marien J-N, Doucet J-L (2011) Enjeux fonciers, exploitation des ressources naturelles et forêts des communautés locales En périphérie de Kinshasa, RDC. Biotechnol Agron Soc Environ

Vieilledent G, Vancutsem C, Bourgoin C, Ploton P, Verley P, Achard F (2022) Spatial scenario of tropical deforestation and carbon emissions for the 21st century. Ecology. https://doi.org/10.1101/2022.03.2.485306

Wunder S (2007) The efficiency of payments for environmental services in tropical conservation. Conserv Biol 21(1):48–58. https://doi.org/10.1111/j.1523-1739.2006.00559.x

Yangambi-Bosunga P (2016) Guide méthodologique pour Le reboisement et L'agroforesterie. MECND-RDC, p 34

**Publisher's Note** Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

## Authors and Affiliations

Adrien Peroches<fnref n="1" />,<fnref n="2" />,<fnref n="3" /> • Emilien Dubiez<fnref n="3" />,⁴ • Adeline Fayolle<fnref n="3" />,⁵ • Lydie-Stella Koutika⁶ • Neville Mapenzi⁷ • Cédric Vermeulen⁵ • Marc Oswald<fnref n="2" /> • Guillaume Lescuyer<fnref n="3" />,⁷

<figure><img src="image_17.png" /></figure>

Adrien Peroches
adrien@agrarian-systems.org

Emilien Dubiez
emilien.dubiez@cirad.fr

Adeline Fayolle
adeline.fayolle@cirad.fr

Lydie-Stella Koutika
ls_koutika@yahoo.com

Neville Mapenzi
nevillemapenzi75@gmail.com

Cédric Vermeulen
cvermeulen@uliege.be

Marc Oswald
m.oswald@istom.fr

Guillaume Lescuyer
guillaume.lescuyer@cirad.fr

<footnote n="1">¹ Agrarian Systems Consulting, Castelnau-le-Lez, France</footnote>

<footnote n="2">² ISTOM, UR ADI-Suds, Angers, France</footnote>

<footnote n="3">³ CIRAD, UR Forêts et Sociétés, University of Montpellier, Campus International de</footnote>
Baillarguet, 34398 Montpellier, France

4 Institut National de Recherche Forestière, Brazzaville, Republic of the Congo

5 Gembloux Agro-Bio Tech, University of Liege, FORIL, Gembloux, Belgium

6 CRDPI, UR 112, Pointe-Noire, Republic of the Congo

7 CIFOR, Bogor, Indonesia