Supplementary material from Soil resistance and recovery during neotropical forest succession
Creators: name: van der Sande, Masha T.
name: Powers, Jennifer S.
name: Kuyper, Thom W.
name: Norden, Natalia
name: Salgado-Negret, Beatriz
name: Silva de Almeida, Jarcilene
name: Bongers, Frans
name: Delgado, Diego
name: Dent, Daisy H.
name: Derroire, Géraldine
name: Marcos do Espirito Santo, Mario
name: Dupuy, Juan Manuel
name: Fernandes, Geraldo Wilson
name: Finegan, Bryan
name: Gavito, Mayra E.
name: Hernández-Stefanoni, José Luis
name: Jakovac, Catarina C.
name: Jones, Isabel L.
name: das Dores Magalhães Veloso, Maria
name: Meave, Jorge A.
name: Mora, Francisco
name: Muñoz, Rodrigo
name: Pérez-Cárdenas, Nathalia
name: Piotto, Daniel
name: Álvarez-Dávila, Esteban
name: Caceres-Siani, Yasmani
name: Dalban-Pilon, Coralie
name: Dourdain, Aurélie
name: Du, Dan V.
name: García Villalobos, Daniel
name: Nunes, Yule Roberta Ferreira
name: Sanchez-Azofeifa, Arturo
name: Poorter, Lourens
Publisher: name: The Royal Society
Year: 2022
Subjects: subject: Ecology
subject: FOS: Biological sciences

description: The recovery of soil conditions is crucial for successful ecosystem restoration and, hence, for achieving the goals of the UN Decade on Ecosystem Restoration. Here, we assess how soils resist forest conversion and agricultural land use, and how soils recover during subsequent tropical forest succession on abandoned agricultural fields. Our overarching question is how soil resistance and recovery depend on local conditions such as climate, soil type and land-use history. For 300 plots in 21 sites across the Neotropics, we used a chonosequence approach in which we sampled soils from two depths in old-growth forests, agricultural fields (i.e. crop fields and pastures), and secondary forests that differ in age (1–95 years) since abandonment. We measured six soil properties using a standardized sampling design and laboratory analyses. Soil resistance strongly depended on local conditions. Croplands and sites on high-activity clay (i.e. high fertility) show strong increases in bulk density and decreases in pH, carbon (C) and nitrogen (N) during deforestation and subsequent agricultural use. Resistance is lower in such sites probably because of a sharp decline in fine root biomass in croplands in the upper soil layers, and a decline in litter input from formerly productive old-growth forest (on high-activity clays). Soil recovery also strongly depended on local conditions. During forest succession, high-activity clays and croplands decreased most strongly in bulk density and increased in C and N, possibly because of strongly compacted soils with low C and N after cropland abandonment, and because of rapid vegetation recovery in high-activity clays leading to greater fine root growth and litter input. Furthermore, sites at low precipitation decreased in pH, whereas sites at high precipitation increased in N and decreased in C : N ratio. Extractable phosphorus (P) did not recover during succession, suggesting increased P limitation as forests age. These results indicate that no single solution exists for effective soil restoration and that local site conditions should determine the restoration strategies.This article is part of the theme issue ‘Understanding forest landscape restoration: reinforcing scientific foundations for the UN Decade on Ecosystem Restoration’.