bluuebunny/crossref_metadata_2025 huggingface dataset:
Economic modelling of a lignocellulosic biomass biorefining industry.
Authors: Epplin F. M. , Mapemba L. D. , Tembo G.
Published: November 2017

This chapter describes a modelling system that could be used to develop an optimal plan for providing a steady flow of lignocellulosic biomass (LCB) to a biorefinery. The model could be used to determine for a specific region, the most economical sources of LCB, timing of harvest and storage, inventory management, biorefinery size and biorefinery location. The model was applied in the case of the state of Oklahoma to determine optimal combinations of LCB feedstock from among grasses produced on Conservation Reserve Program (CRP) land, crop residues (maize stover and wheat straw), perennial grasses (indigenous grasses from native range and introduced grasses from pastures) and dedicated feedstock such as switchgrass (Panicum virgatum). Results indicate, among others, that restricting harvest to CRP acres imposes a rather substantial cost on the industry. For a 2000-t/day biorefinery, limiting feedstock production to CRP land would increase the expected cost to deliver a tonne of LCB to US$69 compared with a cost of US$33 for the multiple feedstock model. The economic model suggests that the cost to deliver a continuous flow of LCB to a biorefinery will depend critically upon the logistics of procuring, harvesting, storing, and transporting the LCB.
Economic impacts of ethanol production from maize stover in selected midwestern states.
Authors: English B. C. , Menard R. J. , Torre Ugarte D. G. de la , Walsh M. E.
Published: November 2017

This chapter provides estimates of economic impacts if stover-to-ethanol plants are established in the current maize producing states of the USA. The economic impact indicators used in the analysis include total industry output, employment, and value-added. Results indicate that an ethanol plant provides substantial estimated economic impacts for total industry output and employment. It is also shown that the number of feasible ethanol plants in each state could vary substantially based on the prices of ethanol and maize stover and plant size. Finally, the economic potential of increased ethanol production can be better summarized when considering the case where producers are guaranteed US$1.35/gal at a break-even price scenario for a 2000-MT/day plant. For this scenario, an estimated 72 plants would be constructed, 8.8 billion gal of ethanol would be produced, US$1.0 billion in gross income to agricultural producers would occur, and an estimated economic impact of US$14 billion in the rural economies of the 10-state region would be realized.
Trends in US poultry housing for energy conservation.
Authors: Worley J. W. , Czarick M. M. , Fairchild B. F.
Published: November 2017

This chapter presents estimates of: (1) the expected energy savings from several technologies being employed in US broiler houses, including wider houses, more efficient ventilation fans, replacing curtain walls with solid walls, litter treatments to reduce ammonia emissions, and circulation fans for heat distribution; (2) the extent to which these technologies are being adopted; and (3) the potential for energy savings attributable to these new technologies on an industry-wide basis.
Experiences co-firing grasses in existing coal-fired power plants.
Authors: Boylan D. M. , Eastis J. , Russell K. H. , Wilson S. M. , Zemo B. R.
Published: November 2017

This paper describes handling, emissions, and performance results generated while testing switchgrass (Panicum virgatum) and other grasses with two co-firing technologies. Ongoing studies to address issues related to the impact of co-firing on fly ash sales and on catalyst performance in selective catalytic reduction nitrogen oxide control systems are also described. Cost estimates associated with generating renewable energy from grass co-firing are presented, based on both current results and expected technology improvements.
Development of genetically engineered stress tolerant ethanologenic yeasts using integrated functional genomics for effective biomass conversion to ethanol.
Authors: Liu Z. L. , Slininger P. J.
Published: November 2017

The topics covered include: metabolic conversion pathways of inhibitors; adaptive response of ethanologenic yeasts to the inhibitors; enhanced tolerance and inhibitor detoxification by biotransformation; tolerance improvement potential; by-product utilization issues; quality control development for microarray studies; genomic expression in response to the inhibitors; and novel strain design and genetic engineering.
Potential for biofuel-based greenhouse gas emission mitigation: rationale and potential.
Authors: McCarl B. A. , Gillig D. , Lee HengChi Lee HengChi , El-Halwagi M. , Qin X. Y. , Cornforth G. C.
Published: November 2017

This chapter examines the first and last of the 4 motivations from institutional and quantitative viewpoints. The institutional section discusses the context in which offsets may be needed and the role that agriculture and forestry may play with an emphasis on biofuels. The quantitative portion extends the work of McCarl et al. [see Annals of Operations Research (2000) 94, 37-55] and Schneider and McCarl [see Environmental and Resource Economics (2003) 24, 291-312] to further consider the potential of biofuel and other possible agriculture/forestry greenhouse gas (GHG) emission offset alternatives in the face of a range of GHG offset prices emphasizing dynamics.
EU structural policies and the ESDP.
Authors: Shucksmith M. , Thomson K. J. , Roberts D.
Published: November 2017

This chapter outlines the relevant features of EU structural and cohesion policy and of the European Spatial Development Perspective (ESDP) itself. The structural policies of the EU are aimed at reducing disparities between different regions and social groups, and at promoting sustainable development and general economic efficiency. Information is presented on the structural funds allocated in rural areas. ESDP concepts applied to agriculture and rural development are discussed.
The territorial distribution of CAP/RDP support.
Authors: Shucksmith M. , Thomson K. J. , Roberts D.
Published: November 2017

This chapter considers the way in which Common Agricultural Policy/Rural Development Policy (CAP/RDP) support has, in practice, been distributed across European territory, where farmers operate in a wide range of economic, social and environmental contexts. The analysis intends to highlight territorial imbalances in the incidence of CAP/RDP support. The results presented are based on a statistical analysis of indicators and data at NUTS3 level over the period 1990-2000, augmented by findings from an EU-wide review of literature. The chapter considers the incidence of Pillar 1 and Pillar 2 support and LFA payments separately before considering more generally the influence of farm type, accessibility and region type on the distribution of support.
Adjustments and impacts of the CAP/RDP.
Authors: Shucksmith M. , Thomson K. J. , Roberts D.
Published: November 2017

This chapter reviews and synthesizes a number of case studies of the regional impact of the EU's Common Agricultural Policy/Rural Development Policy (CAP/RDP). The case studies were undertaken to provide deepened insight into the core issues, i.e. detailed empirical information on the territorial incidence of the CAP/RDP, and more evidence on the impact of CAP/RDP measures on the economic, social and environmental situation in regions of different types. The focus is on more differential territorial information about the application of CAP/RDP instruments, in particular the territorial (mainly regional) effect of specific schemes, and/or the combined effect of policy programmes. The policy instruments selected for case study are four major sub-programmes/schemes of CAP Pillar 2 (agri-environmental programme, farmers' early retirement scheme, less-favoured areas scheme, and LEADER programme). In addition, the SAPARD programme designed as a pre-accession instrument for countries in Central Europe is studied, and two countries (Ireland and (pre-accession) Poland) have been singled out for case-study treatment at a broader level. The Irish study takes a number of contemporaneous economic developments and support schemes into account, while the Polish one examines the practical details of implementing the SAPARD programme in that country.
The CAP/RDP reforms in the EU-15 and the NMSs.
Authors: Shucksmith M. , Thomson K. J. , Roberts D.
Published: November 2017

This chapter summarizes existing analyses of the Common Agricultural Policy/Rural Development Policy (CAP/RDP) reforms (mainly the original Mid Term Review (MTR) proposals of July 2002). It starts with a description of the Commission's MTR proposals, and reviews some basic analysis. The next section shows the results of quantitatively analysing at a NUTS3 level some estimates from one of these studies (the Common Agricultural Policy Regional Impact (CAPRI) study). Finally, the implications of CAP reform for the new member states in Central Europe are discussed. It is indicated that CAP reform proposals are expected to generate a sustainable improvement in the medium-term perspectives of the agricultural sector of the EU-25. In the new member states, CAP reform could secure income gains, generated by enlargement, which could reach up to 45% when taking into account the phasing-in of direct payments and rural development measures. Although the territorially differentiated effects of the reform are rather difficult to calculate, it is concluded that the reform proposals would have diverging impacts across regions and the various sectors, leading to declines in the milk and (food) oilseed sectors, broadly stable development in the cereal sector, and significant gains for the meat sector.
Ways forward in rural development.
Authors: Shucksmith M. , Thomson K. J. , Roberts D.
Published: November 2017

Following a background discussion on the key dimensions of rural development in the EU, this chapter highlights some examples that present either innovative approaches or representative use of the framework provided by the EU's Rural Development Regulation. Examples have been selected so as to address the different instruments analysed and reflect the on-going policy discussion on future reform. The cases presented include: (1) differentiation of compensatory allowances for less favoured areas in Austria; (2) the Ireland Rural Environmental Protection Scheme (REPS); (3) CTE (contract territorial d'exploitation), France; (4) "Cheese Route Bregenzerwald", LEADER, Austria; (5) rural tourism in Italy; (6) PRODER (Programa Operativo de Desarollo y Diversificación Económica de Zonas Rurales) Andalucia, Spain; and (7) POMO (Rural Programme Based on Local Initiative) and POMO+, Finland. The mainstreaming of the LEADER approach to rural development is then discussed.
Turkey's economy and regional income distribution.
Authors: Oskam A. , Longworth N. , Yİldİz A.
Published: November 2017

This chapter provides the macroeconomic context within which other chapters analyse agrifood issues and the consequences of Turkey's accession to the EU. After a brief overview of the economy in Section 2.2, Section 2.3 gives information on economic growth, inflation, employment, exchange rates, trade and the balance of payments on current account. The Turkish economy has gone through a period of instability and high inflation, which makes it difficult to measure the underlying growth trend. The growth of Turkey's economy will, however, strongly influence its future position relative to the European Union, and will, together with the exchange rate at and after accession, determine the size of budgetary flows. Section 2.4 gives a brief discussion of this issue. Section 2.5 analyses inter-household and regional income distribution in some detail, since large regional differences in income in an acceding country have implications for targeting EU structural and rural policy.
Agricultural production, prices and trade.
Authors: Longworth N.
Published: November 2017

Section 2 of this chapter outlines the role of agriculture in the general economy of Turkey, showing its shares in GDP, employment and foreign trade. Section 3 assesses the importance of land and labour for Turkish agriculture. Section 4 covers agricultural production: its size, diversity and economic value, with more detail for specific sectors including field crops, fruit and vegetables and livestock, and the agronomic production potential of Turkey. Section 5 looks at output price indices for agriculture, as well as trends in real prices for specific agricultural products. Turkish output prices are compared with those of the EU-15. Section 6 addresses agricultural incomes in Turkey, compared to agricultural incomes in the EU-15. Section 7 presents self-sufficiency levels and outlines Turkey's foreign trade in agricultural products.
Turkey's rural population and agricultural workforce.
Authors: Burrell A.
Published: November 2017

Using data for 1999, 2000 and 2003, this chapter describes Turkey's rural population and agricultural workforce. It examines urban-rural differences in labour force participation and unemployment. Education levels are reported, as well as the health and nutritional status, and the incidence of poverty, among the rural population. Two conclusions emerge from this overview. First, improving education provision, access, and attainment levels must be a top priority for Turkey in the coming years. Second, the duality of Turkey's economy is epitomized by the third of its population that remains in agricultural employment.
Agricultural and food industry structure.
Authors: Berkum S. van
Published: November 2017

This chapter describes the structure of all components of Turkey's agribusiness cluster, which includes the upstream sectors (input industries and financial services) and downstream sectors (agrifood industries) as well as the primary agricultural sector. In addition, the structures of the wholesale and retail sector are presented. The chapter concludes with a section on how the linkages between farmers, processors, traders and retail can be characterized in Turkey.
Overview of agricultural, food, rural and structural policies.
Authors: Oskam A.
Published: November 2017

This chapter considers three partly related policy areas in Turkey: agricultural, food and rural development/structural policy. Most attention is given to agricultural policy because of its recent reform and its relevance for the EU. The agricultural policy section starts with the policy-making process, because this is seen as one of the explanations for the inconsistent use of policy instruments over time. The Agricultural Reform and Implementation Project (ARIP) is discussed in detail. The food policy section focuses on food safety and quality. The rural policy section points out key differences between Turkey and the EU. Structural policy in Turkey has taken a special form, namely, as part of the policies relating to state economic enterprises and agricultural sales cooperative unions. Rural development policy takes the form of rural development plans, which have sometimes covered infrastructural elements.
Environment and agriculture.
Authors: Vílchez I. M.
Published: November 2017

This chapter studies the relationship between agriculture and the environment in Turkey. Sections examine: (i) the environmental impacts of Turkish agriculture (on water resources, on the soil, on climate change); (ii) the extent to which agri-environmental concerns are dealt with by current policies (with regard to environmental, agricultural and rural development policies); (iii) the institutional arrangements for enforcing legislation on agriculture and the environment; (iv) the current state and prospects for organic farming; and (v) biodiversity in Turkey and related institutional developments. It is concluded that the main environmental impacts of agriculture in Turkey involve the degradation of water and soil due to uninformed farming practices, namely, the overuse of water and chemicals. Environmental policy in Turkey has improved in terms of new legislative instruments. However, it is argued that institutions dealing with agri-environmental issues seem to be poorly coordinated and there seems to be a lack of effective implementation at local level.
Animal and plant health in Turkey.
Authors: Burrell A.
Published: November 2017

The first section of this chapter presents an overview of animal health in Turkey. It covers (i) the most infectious and economically significant animal diseases (List A diseases), (ii) less infectious diseases that also have serious economic consequences (List B diseases) and (iii) diseases that can be passed from animals to humans (zoonoses), followed by discussion of the legislative framework and the resources available for adequate animal health control. The second section focuses on plant health and presents information on the various pests and diseases by category of crop, and the various methods adopted by Turkish farmers to prevent or control them. Regulations concerning plant health are also examined. It is concluded that (1) much institutional change is still needed before Turkey can effectively implement the veterinary and phytosanitary acquis of the EU, and that (2) this holds particularly for the animal sector.
Consequences for the EU-27 of enlargement to Turkey.
Authors: Oskam A. , Longworth N. , Vílchez I. M.
Published: November 2017

This chapter considers the main consequences of Turkey's accession for the EU-27 regarding agriculture and agricultural policy, the food industry, the likely budget flows and other less tangible, related consequences. Sections cover: (i) assumptions regarding exogenous policy trends; (ii) specific agricultural policy changes likely to be made in preparation for Turkish accession; (iii) consequences relating to the single market and to EU agribusiness/food industry; (iv) assumptions in calculating budget payments and the decision-making background to these flows, including structural fund spending; and (v) calculations of budget flows/payments under the CAP. It is concluded, among others, that Turkey's accession to the EU will not only reduce average EU per capita income by about EUR 3150 (at 2015 prices) but would also bring a country with large differences in institutional performance into the EU. This could divert attention and funding away from a growth strategy for the more developed regions of the EU, while also reducing the emphasis given to further improvements in areas of concern like food safety, food quality, environmental quality, veterinary and phytosanitary standards, and animal welfare.
Expected consequences for Turkey of EU entry in 2015.
Authors: Temel T.
Published: November 2017

This chapter explores the likely consequences for Turkey's agricultural and agrifood sectors of future EU membership. Two groups of issues are explored. The first set of issues relates to Turkey's ability to assume the obligations of the acquis regarding competition rules, property rights, and free movement of agricultural products by 2015. The second set of issues relates to the implications of membership for agricultural markets in Turkey and their capacity to cope with competitive pressure and market forces implied by the EU single market. The emphasis is on how the policy changes necessary for membership affect the functioning of agricultural and food markets. Sections of the chapter discuss: (a) the key assumptions underlying the discussion; (b) the implications of EU membership for Turkish policies that relate to agriculture, food and rural development, international trade, and agri-environmental interactions; (c) the implications for agrifood chain developments; (d) implications for the institutional framework of Turkish agriculture; (e) budget consequences (payments to Turkey under the CAP); and (f) selected studies on Turkish accession.
Periphyton structure, diversity and colonization.
Authors: Azim M. E. , Asaeda T.
Published: November 2017

The morphological characteristics, biochemical composition, taxonomic composition and diversity, as well as the colonization process and sloughing and recolonization of periphyton are reviewed. The proximate composition of periphyton grown on different substrates in different habitats, and a list of some periphyton taxa in different habitats (i.e., ponds, lake, marsh/wetland, stream/river and estuary/sea) are given.
Periphyton in the aquatic ecosystem and food webs.
Authors: Wetzel R. G.
Published: November 2017

This paper presents an in-depth insight into the role of periphyton in aquatic food webs and as a critical metabolic component of aquatic ecosystems. Energy and organic matter fluxes in general, growth regulation and habitat variables, community metabolism and links between periphyton and higher trophic levels are discussed. Recycling is also discussed as the key to nutrient fluxes and maximizing productivity of periphyton. Finally, modulation of periphyton by light availability and by mortality and losses, and the potential effects of global changes in climate and related environmental conditions are also covered.
Periphyton in freshwater lakes and wetlands.
Authors: Goldsborough L. G. , McDougal R. L. , North A. K.
Published: November 2017

The ecology of algae associated with benthic habitats in freshwater lentic environments such as lakes and wetlands and the primary biotic and abiotic factors (i.e., nutrients, light, hydrodynamics and herbivory) affecting their productivity are reviewed. There is a growing consensus that periphyton in these ecosystems provide a plentiful and important resource for subsequent trophic levels, sometimes exceeding that of planktonic algae and macrophytes.
Utilization of periphyton for fish production in ponds: a systems ecology perspective.
Authors: Dam A. A. van , Verdegem M. C. J.
Published: November 2017

An attempt is made to synthesize the available knowledge on the processes underlying periphyton-based fish production in ponds into a quantitative framework that can help to understand the impact of periphyton substrates on the main nutrient cycles in ponds. A simple model of phytoplankton production and fish growth in ponds is constructed and parameterized to simulate fish production with a realistic level of fertilizer input. To this simple model, a periphyton component is added to evaluate the effect of the periphyton loop on fish production. Experimentally derived data from Bangladesh were used to parameterize the models. Nitrogen is chosen as the model currency.
Traditional brush park fisheries in natural waters.
Authors: Welcomme R. L.
Published: November 2017

Brush parks are designed to mimic the natural dry season habitat of many species of fish and crustaceans that regularly use the floating vegetation and submerged branches associated with riverbanks and shores of floodplain lakes for refuge, food and reproduction. Evidence suggests that their mode of operation is more complex and that under the right circumstances, brush parks can contribute to the overall production and well being of fisheries in the water bodies where they are found. In view of the potential of such methods to enhance the fisheries of the water bodies in which they are installed, this chapter reviews the various types of tropical fish parks. Their construction from wood, branches and floating vegetation (including the species used), ecology that mirrors the riparian vegetation in provision of food and shelter, uses, operation, management, and the social, economic and environmental (deforestation, sedimentation) impacts are also described. Management strategies are proposed to resolve most of the physical and biological objections to the use of these fish parks.
Periphyton as biological indicators in managed aquatic ecosystems.
Authors: Sabater S. , Admiraal W.
Published: November 2017

This paper focuses on the pros and cons of using periphyton (phototrophic biofilms) as monitoring tools in natural and managed aquatic ecosystems. The structural (biomass, community composition) and physiological (pigment composition, photosynthesis) descriptors of periphyton are critically examined to evaluate their use as biological indicators. Different responses of biofilms to physical, chemical and biological disturbances (e.g. extreme water pH and excess nutrients) are discussed. An annotated list of the methods used for monitoring managed aquatic systems using periphyton is given. The range of methods presented includes methods to determine the general state of biofilms/periphyton as well as specific methods in relation to growth or structure. A combination of methods can be made depending on the type of information required.
Effect of periphyton on water quality.
Authors: Milstein A.
Published: November 2017

This paper focuses on the mutual effects among periphyton, phytoplankton, water quality, different cultured fish species and management procedures in periphyton-based earthen fish ponds in Bangladesh. The periphyton community developing on hard surfaces interacts with other communities in the pond. Two types of such interactions are discussed, viz., periphyton-environment relationships in the absence of grazing pressure by cultured organisms, and periphyton-environment-cultured organisms relationships. These interactions and the water quality resulting from them are different in the absence of large fish biomass characteristic of fish culture ponds.
Periphyton-based pond polyculture.
Authors: Azim M. E. , Wahab M. A.
Published: November 2017

A brief history of fish polyculture system and pond polyculture (in particular) as an age-old practice in Asia is provided. A list of suitable fish species for polyculture is also given. The benefits of traditional polyculture can also be enjoyed in periphyton-based aquaculture systems. The periphyton-based Indian major carp (Labeo rohita, L. gonius and L. calbasu) polyculture and carp-freshwater prawn polyculture are described based on experiments carried out in Bangladesh. The intensification of periphyton-based polyculture and the possible mechanisms for enhanced fish production in periphyton-based systems are discussed. Also examined are some factors influencing the increased fish production in periphyton systems such as provision of additional food and shelter, opportunity for higher nutrient efficiency, better environment through improved water quality, and optimizing the synergistic effects. Finally, the applicability of the periphyton technology and its socioeconomic impacts are discussed.
Periphyton-based aquaculture in Asia: livelihoods and sustainability.
Authors: Bunting S. W. , Karim M. , Wahab M. A.
Published: November 2017

The substrate selection, environmental impact and management aspects of periphyton-based aquaculture for sustainable fish production in Asia are described.
Air pollution and forests in heavily industrialized regions: an introduction.
Authors: Oleksyn J. , Innes J. L.
Published: November 2017

Air pollution represents a threat to many forests, particularly in the Russian Federation. Various types of air pollution affect forests, with the most significant pollutants being sulfur dioxide, fluorides, heavy metals and ozone. In the past, these have been responsible for the destruction of substantial areas of forest. In North America and Western Europe, such effects have now been brought under control, and steps are being taken to aid the recovery of damaged ecosystems. Eastern Europe remains in a transition stage, with only a poor understanding of the complex factors causing the declines of specific forests. In the Russian Federation, the pollution in some areas remains at very high levels, although economic developments in the 1990s have resulted in lower pollution emissions associated with lower production. However, the damage in some areas of the country continues to expand, with more than 1 million hectares in the vicinity of Noril'sk, Siberia, showing visible signs of damage, and an estimated 7 million hectares affected. International initiatives to control pollution on a multilateral or bilateral basis have resulted in significant improvements. Similar initiatives by the research community could result in major benefits.
The impacts of air pollution on the northern taiga forests of the Kola Peninsula, Russian Federation.
Authors: Rigina O. , Kozlov M. V.
Published: November 2017

Copper-nickel smelters in the Kola Peninsula of Russia, emitting 350-750 kt of sulfur dioxide annually, have caused visible damage to forests over 39 000 km2 and forest death over 600-1000 km2. Individual and population responses of the forest-forming woody plants to pollution are reasonably documented, whereas changes in other components of the forest ecosystems are less well known, and almost no data exist about pollution effects on the functioning of the ecosystems present in the area. The spatial representativeness of the plots used in earlier studies was insufficient for the detailed mapping of forest condition in the region. Remote sensing analysis, supported by ground truth data, has overcome this problem, and has also provided information on the history of pollution impacts in the area. Although the development of predictive models has been delayed by the limited information available about both the emissions and their impacts, forest degradation is expected to continue for some time, even if the emissions are terminated.
Gene flow in forest trees.
Authors: Hamrick J. L. , Nason J. D.
Published: November 2017

Pollen and seed immigration into forest tree populations promotes genetic continuity by transferring genetic variation among populations. The homogenizing effects of gene flow, therefore, counter the disruptive effects of selection and genetic drift. Gene flow rates are typically estimated in two ways: indirectly from the distribution of genetic variation among populations or directly via the detection of immigrant pollen and seed. Gene flow rates estimated indirectly from spatial genetic structure measure effective rates of immigration pooled over several populations and generations. Reviews of the distribution of allozyme genetic variation demonstrate that tree species typically possess more genetic diversity than herbaceous species and that more of this variation occurs within individual populations. These data support the conclusion that tree species generally experience more gene flow than most herbaceous species. In only a few studies have the relative contributions of pollen and seed flow been distinguished. These indirect estimates indicate that pollen dispersal is responsible for much higher levels of gene migration than seed dispersal. Genetic markers can be used to directly estimate gene flow by detecting immigrant pollen and seed genotypes. The relatively few direct measurements of gene flow into tree populations demonstrate that gene immigration via pollen is often more than 25% over distances of several hundred metres. Direct estimates of seed movement are rare but indicate that seed flow is more restricted than pollen flow over comparable distances. This conclusion is tentative, however, as seed movement has not been characterized for tree species with light, wind-borne seeds or with strong-flying animal vectors.
Effects of logging and other forms of harvesting on genetic diversity in humid tropical forests.
Authors: Ratnam W. , Boyle T. J.
Published: November 2017

Commercial harvesting of timber through logging is a major form of disturbance in many areas, but the variety of products harvested from tropical forests is immense: wood, fruit and other foods, medicinal plants, construction materials and many more. Commercial logging has been separated from other types of human use to reflect the relative importance of logging in all types of forest. In a comprehensive study of logging in tropical forests, genetic diversity (expected heterozygosity, He, for isozyme data and Shannon Diversity Index, H, for RAPD data) was reduced by 5.0-23.4% after logging for five species with different life history strategies. Generally, the order of reduction in number of individuals corresponded with the order of reduction in genetic diversity. Daemonorops verticillaris exhibited the highest loss of alleles (13.8%) most probably due to death of individuals following logging damage to supporting trees and being trampled during extraction of felled trees. No significant differences in outcrossing rates were observed between logged and unlogged stands for Shorea leprosula and Dryobalanops aromatica. No adverse changes in genetic diversity measures of Parkia speciosa, Scaphium macropodum, Shorea leprosula, Garcinia malaccensis, Daemonorops verticillaris and Labisia pumila were detected in two regenerated stands (13.5% and 40.7% disturbances) compared to an unlogged stand in the mixed dipterocarp lowland forest indicating maintenance of genetic diversity in regenerated stands after a single low intensity logging event. In comprehensive studies on collection of non-timber forest products in the Biligiri Rangan Hills of south India, a significant effect on recruitment of Phyllanthus emblica, the fruits of which are harvested for food and as a base for numerous traditional medicines, was observed. Harvesting of fruits or flowers tend to have a more direct or dramatic effect on regeneration and genetic diversity than harvesting of leaves, bark or other non-reproductive parts of the plants.
Forest fragmentation.
Authors: Young A. G. , Boyle T. J.
Published: November 2017

Forest fragmentation is a pervasive threat to forest ecosystems throughout the world. Reduced overall numbers of individuals, decline in mean population sizes and the separation of forest remnants by non-forest land can affect the main genetic processes of genetic drift, gene flow, selection and mating. The three most obvious possible genetic effects of forest fragmentation are: (a) loss of genetic diversity at the population and species level (b) increased interpopulation structure (c) increased inbreeding. Responses are likely to vary depending on the ecological characteristics of the species involved, such as their breeding system, dispersal syndrome, longevity and ploidy level. Although empirical data are sparse, results suggest that while genetic variation may decrease with reduced remnant population size, not all fragmentation events lead to genetic losses, with the interaction between local population size and isolation being important in determining levels of genetic diversity. Similarly, while inbreeding may increase in fragmented populations, sometimes even fairly dramatic shifts in pollinator guilds due to fragmentation do not appear to affect the rate of cross fertilization. Overall, genetic effects of fragmentation are less easy to predict than expected, being determined, as they are, by the scale of fragmentation, the biology of the affected species and their associated pollinators and dispersers. More data are required in order to make sensible predictions regarding the likely response of a forest ecosystem to a given fragmentation event.
Effects of environmental pollution on the genetics of forest trees.
Authors: Geburek T.
Published: November 2017

Important aspects of environmental pollution on the genetics of forest trees are reviewed and include: (a) a description of the variation in response to gaseous and metal pollutants among forest tree species and within-species variation on the family and clonal level; (b) heritability of plant response to gaseous pollutants; (c) a genetic assessment of polluted tree populations by means of gene markers; (d) altered gene expression triggered by environmental stress; and (e) investigation of whether environmental pollution triggers evolutionary processes in forest tree populations. In most forest tree populations (provenances), differences in resistance to gaseous and non-gaseous pollutants exist. Generally slow-growing and genetically highly variable tree populations seem to be less affected by different gaseous pollutants than fast-growing and genetically less variable tree populations. Intraspecific variation in resistance to pollutants increases from the provenance to the family level and is greatest among single trees (clones). Heritability estimates of resistance to gaseous air pollutants in forest trees are mainly high. Inheritance to pollution seems to be polygenic and in some cases is probably pleiotropic with respect to other stress factors. While genetic control of response to environmental stress (e.g. number of genes, gene dose, epistatic effects) is often known in herbaceous plants, knowledge in forest trees is still missing. Results of gene marker studies in polluted forest tree populations indicate that groups of trees (subpopulations, artificial subsets) with high genetic variation tend to be more tolerant to heterogeneous environmental stress than less variable ones. Environmental pollutants repress and/or induce plant genes.
Sampling the gene pools of forest trees for ex situ conservation.
Authors: Brown A. H. D. , Hardner C. M.
Published: November 2017

A population approach to sampling the genetic resources of forest species is inherent in the prominence of the 'provenance' concept in forest management. It is known from the sampling theory for selectively neutral alleles that the main quantity of interest, the allelic richness or number of alleles per locus actually present in a sample, is expected to increase linearly with increasing population size. In contrast, the allelic richness of the sample increases in proportion to the logarithm of the sample size. This implies that the reward for extra sampling effort at a site follows the law of diminishing returns. An adequate sample is defined as one that includes with 95% certainty, at least one copy of an allele with arbitrary frequency 0.05 and this requires 59 unrelated gametes. Larger samples are needed when there are several alleles at the boundary frequency - the worst-case scenario of 20 equally frequent alleles requires a doubling of the size. Fruits are often the unit of sampling in trees species and we examine the effect of single versus multiple paternity of fruit on the number of fruit required. When paternity is unknown, a worst-case scenario is that all the fruit from one individual form a single full-sib array. It follows that fruit should be sampled from at least 15 trees to be sure of an adequate sample. Strategies for the sampling of many populations depend on the amount of genetic diversity in each population and the genetic divergence between them. The best strategy accords priority to so-called 'local' common alleles, or those that exceed 0.10 in frequency in only one region or population. Such alleles make up an appreciable fraction (10-20%) of the genetic resources of trees. This strategy is in line with the provenance concept and contrasts with samples of 172-plants-per-species, which is an approach recently advocated by Lawrence and colleagues.
Magnitude and implications of gene flow in gene conservation reserves.
Authors: Adams W. T. , Burczyk J.
Published: November 2017

A practical means of long term genetic conservation in forest trees is to establish natural (in situ) populations (i.e. gene resource management units, GRMUs) or ex situ plantings as gene conservation reserves. Results from pollen contamination studies in conifer seed orchards, however, indicate that gene flow in such reserves could be extensive. Although gene flow can be beneficial in terms of introducing new genetic variants, immigration of genes from domesticated populations is likely to reduce total genetic diversity within reserves and potentially lower their fitness. The prudent position on gene flow in reserves, therefore, is to limit it as much as possible. Pollen gene flow can be eliminated in ex situ plantings by controlled mating. If controlled mating is not feasible, applying pollen management techniques to increase pollen production within the plantings relative to external sources can minimize gene flow. Strategies for reducing gene flow in GRMUs are to make reserves as large as possible, include buffer zones around reserves (perhaps planted with an exotic species), and to assure that natural regeneration, or seed collection for artificial regeneration, occurs in heavy seed-crop years. Gene flow in forest trees is still poorly understood and the effectiveness of various approaches to limit gene flow in reserves, especially in GRMUs, cannot be quantified with any accuracy. Thus, research on gene flow in forest trees should receive high priority.
Criteria and indicators for the conservation of genetic diversity.
Authors: Boyle T. J.
Published: November 2017

Conservation of genetic diversity is usually one aspect of more complex management goals. It is associated with sustainable forest management, which is a concept that is difficult to measure or assess. The use of criteria and indicators, which outline conditions that should be met if forest management is to be deemed sustainable, offers a solution to this problem. The most important characteristic of an effective indicator is the practicality of assessment in a short period. As genes are inherently difficult to detect, this has usually resulted in the adoption of vague or very indirect indicators of genetic diversity. An approach is described which uses the assessment of processes which maintain genetic diversity as surrogate measures of genetic diversity itself. Using this conceptual framework, a number of indicators and verifiers (the variables actually measured) are proposed. Even given such an approach, problems related to the establishment of thresholds and choice of species to assess remain. Possible solutions to these problems are proposed, but empirical testing is required to verify the validity of such an approach.
Chile: the evolution of the Agricultural Advisory Service for small farmers: 1978-2000.
Authors: Berdegué J. A. , Marchant C.
Published: November 2017

This chapter describes and analyses four stages that can be recognized in the evolution of Chile's Agricultural Advisory Services (AAS) for small farmers: period of maximum liberalization (1978-83); period of maximum uniformity (1983-90); the 'Improvement Plan' (1990-96); and the AAS (1997-2000). It is concluded that Chile's extension system has evolved from one promoting increased yields of basic commodities to one which is now focused on the competitive participation of small farmers' economic organizations in an open economy. Some of the most important design issues that have driven the changes put in place through time are outlined.
Federal Republic of Germany: contracting for agricultural extension in Thuringia.
Authors: Currle J. , Hoffmann V. , Kidd A. D.
Published: November 2017

This chapter examines the changes in extension in Thuringia, Germany. For instance, a significant proportion of the state budget for extension has been contracted to private extension companies since 1998. The impacts of contracting out are discussed, as well as lessons learned from Thuringia's experience.
The Netherlands: going Dutch in extension, 10 years of experiences with privatized extension.
Authors: Proost J. , Duijsings P.
Published: November 2017

This chapter examines the privatization of the Netherlands' national agricultural extension and research services in 1990. It outlines some of the most outstanding changes in terms of: client orientation; skills; planning; and monitoring clients. Contracting for advisory services is discussed, as well as the supportive processes for the advisory process. The effects of privatization are discussed as well.
Madagascar: contracting for community forest management.
Authors: Laub-Fischer R.
Published: November 2017

This paper describes the contractual approach developed and introduced by the integrated forestry project, as implemented by the Ministry of Water and Forest and the Deutsche Gesellschaft fuer Technische Zusammenarbeit in Madagascar, which aims to improve sustainable natural resources management through community participation.
Vietnam: contracting for extension training in participatory planning methods.
Authors: Dinh Duc Thuan Dinh Duc Thuan , Nguyen Ba Ngai Nguyen Ba Ngai , Paul B.
Published: November 2017

This chapter deals with the training contract executed during January-December 1997 between the World Food Programme Project 5322 'Smallholder Forestry Development in Five Northeastern Provinces of Vietnam' and the Social Forestry Training Centre at the Vietnam Forestry University. The impact, replicability, and sustainability of the changes that were brought about through the contract are discussed, as well as the lessons learned from the contracting process.
Portugal: contracting for IPM extension by the Association for Viticultural Development in the Douro Valley.
Authors: Cristóvão A. , Alves F. , Koehnen T.
Published: November 2017

This chapter describes the Association for Viticultural Development in the Douro Valley's (ADVID) contracted integrated pest management extension. The impact, sustainability, and replicability of the extension contracts are discussed, as well as the lessons learned from ADVID's experience.
China: from government-driven Group Contracting Extension to farmers' need-oriented contracting extension: the case of Xinyang Prefecture in Henan Province.
Authors: Liu YongGong Liu YongGong
Published: November 2017

This chapter describes the 'Group Contracting Extension' (GCE) system in Xinjiang Prefecture, Henan Province, China. The impacts, sustainability, and replicability of GCE are discussed, as well as the lessons learned from the GCE case.
Finland: a long history of contracting for agricultural extension.
Authors: Riikka Rajalahti Riikka Rajalahti , Eija Pehu Eija Pehu
Published: November 2017

This chapter on contracting for agricultural extension in Finland is comprised of two cases: contracting by the national, although privately based Rural Advisory Centre; and contracting between agribusinesses, the university and growers. The impacts of contracting and the critical factors for the success of extension contracts are discussed.
Uganda: private sector secondment of government extension agents.
Authors: Crowder L. van , Anderson J.
Published: November 2017

This chapter contrasts theoretical and practical experiences in contracting of extension services in Uganda. Variations of and options for contracting extension are discussed. The impacts, sustainability, and replicability of extension contracts are also discussed. Recommendations to improve extension contracting are then presented.
The place of sugar in regional and multilateral trade negotiations.
Authors: Josling T.
Published: November 2017

This chapter surveys the treatment of sugar in regional, plurilateral and multilateral trade agreements (particularly those involving Europe and North America), and in the World Trade Organization Uruguay Round Agreement on Agriculture. This chapter also assesses the prospects for significant trade liberalization at regional and multilateral levels.
Latin American sweetener markets: economic reform and regional integration.
Authors: McCoy T. L.
Published: November 2017

This chapter examines the political and economic changes that have taken place in Latin America and the Caribbean (referred to inclusively as Latin America) and their implications for sweetener markets. Particular attention is given to processes of economic reform and regional integration and their consequences. It is concluded that the political and economic changes are all in the direction of opening up the sweetener market to market forces and to greater competition. However, these changes may occur less rapidly and less completely in the sugar industry (given the prominence of the industry and its political clout) than it will in all other agricultural sectors of Latin America.
Managing Canada-U.S. sugar trade in the North American context.
Authors: Marsden S.
Published: November 2017

This chapter discusses the position of the Canadian sugar market in the context of a distorted North American Free Trade Agreement and global sugar economy. It also deals with recent trade controversies between Canada and the USA, including the importation of sugar-containing products. The chapter concludes by exploring the prospects of Canadian sugar.