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The use of biomass as feedstock for energy is often associated with increased claims on land, competition with food production and impacts on other ecosystem services. Studies on sustainability aspects of bioenergy production often indicate biodiversity as a key concern. This article presents a first comprehensive review of published impacts of bioenergy crop production on biodiversity, evaluates the drivers and pressures of biodiversity change and summarizes current trends and impacts. The review provides insight into the types of biodiversity indicators applied under a range of conditions and the mitigating measures proposed to minimize negative impacts or realize biodiversity benefits. The 53 selected publications give diverse results that are explained by the various spatial scales, production systems and regions, time horizons, methodologies and biodiversity indicators used. Reported impacts depend on initial land use and are mostly negative, especially in tropical regions. The impacts of second generation bioenergy crops tend to be less negative than first generation ones, and are in some cases positive (at the field level), in particular in temperate regions. Land-use change appears as the key driver of biodiversity change, whereas the associated habitat loss, alterations in species richness and abundance are the main impacts addressed. Such changes are often paired with the (initiation of a) process of biological homogenization. The article confirms that concerns about the expansion of bioenergy crop production not only relate to the direct effects on biodiversity by replacing natural vegetation, but increasingly to indirect effects as well. These effects have, however, shown to be difficult to quantify. At the same time, the land sparing vs. land sharing debate receives growing attention, whereas little evidence exists in bioenergy literature on the impacts of large-scale application of these strategies on (agro)biodiversity. Following the findings of the review, the article finally provides recommendations for future research.

Large-scale development projects often overlap forest areas that support the livelihoods of indigenous peoples, threatening in situ conservation strategies for the protection of biological and cultural diversity. To address this problem, there is a need to integrate spatially-explicit information on ecosystem services into conservation planning. We present an approach for identifying conservation areas necessary to safeguard the provision of important ecosystem services for indigenous communities. "Community use zones" (CUZs) were generated using participatory mapping methods that identify place values indicating significant hotspots for ecosystem services. Using principles from landscape ecology, these areas are buffered to provide connectivity and to delineate ecosystem service delivery areas. We demonstrate the use of CUZs for five villages in southern Suriname (n = 191 participants) to inform the South Suriname Conservation Corridor project. The mapped data reveal overlapping hotspots for different ecosystem services depicting multifunctional landscapes that provide an empirical foundation for delineating CUZs. In the absence of legal and traditional land rights for indigenous people, CUZs based on the provision of ecosystem services provide a defensible, spatially explicit approach for integrating indigenous needs into regional conservation plans in southern Suriname. We discuss the utility of CUZ maps for promoting land tenure and security and as a basis for collaborative governance in indigenous and community-conserved areas (ICCAs).

Forest degradation is a major source of greenhouse gas emissions. In the Brazilian Amazon it is responsible for 20 per cent of total emissions (Asner et al. 2005). In Indonesia, the forest stock is decreasing by a rate of six per cent a year, only one-third of which is due to deforestation (Marklund and Schoene 2006). In Africa, the annual rate of degradation is almost 50 per cent of the deforestation rate (Lambin et al. 2003). In 2007, the Conference of the Parties (COP 13) to the United Nations Framework Convention on Climate Change (UNFCCC) acknowledged the importance of degradation and included it in the proposed mechanism for reducing emissions from deforestation and forest degradation (REDD). Addressing degradation has other important benefits, since it reduces the forest’s capacity to adapt to climate change and their ability to provide ecosystem and livelihood services.

Tropical forests harbor the largest share of all terrestrial biodiversity, including 62% of all terrestrial vertebrate species. Of the remaining tropical forests, more than one-quarter are designated as logging concessions, potentially putting wildlife at risk. Forest certification systems like the Forest Stewardship Council (FSC) claim that they address threats to biodiversity, but studies have to date not resulted in robust verification of impacts of certified logging on wildlife communities due to limitations in research design and scale. Measuring impact is important for informed decision-making and data-driven policies. For this, reliable population monitoring is a prerequisite. In this thesis the general aims are to assess whether wildlife is more effectively conserved in FSC-certified logging concessions than in non-FSC concessions, and to explore how wildlife populations can best be monitored in tropical forests. I start this thesis by reviewing the applications of the three main monitoring methods to provide guidance on wildlife monitoring in tropical forests. Then, I examine the knowledge gap concerning the impacts of FSC-certified forestry, by assessing whether wildlife is more effectively conserved in FSC-certified logging concessions than in non-FSC concessions. The data were gathered by using camera traps in fourteen forestry concessions in Western Equatorial Africa. I found that FSC-certified forestry benefits mammals when compared to non-FSC forestry, with the most pronounced positive impacts for mammals weighing 10 kg and more. Next, I develop and test two wildlife monitoring methods: the use of sound for primate monitoring, and the use of soundscapes as a proxy for the overall biodiversity in a forest. Species-specific monitoring using sound covers a different species range than camera traps. However, sound monitoring requires automated classification for it to be useful. For soundscapes, interpretation of changes in the soundscape and quantification of individual species’ contributions are the main challenges, as well as interpreting the relationship between the structure of the soundscape and local landscape heterogeneity. Further development and enhancement of wildlife monitoring methods is essential for impact verification and improvement of forest certification. Improved wildlife monitoring methods may also aid the development of biodiversity credit systems, potentially yielding new revenue streams for conservation.

Mudbanks are pertinent features that can be found along the 1,500-km long coastline of the Guianas. These mostly subtidal banks migrate from the mouth of the Amazon River in Brazil, along the coasts of French Guiana, Suriname and Guyana to the Orinoco Delta in Venezuela. When present the protect the coasts against incoming waves and simultaneously provide a source of sediment for coastal expansion and consequential mangrove colonization. Due to the alternating phases of erosion and expansion, that can last up to 10 – 15 years, is remains difficult to implement long-term coastal management strategies in the Guianas. This is especially true for coastal protection, nature conservation, CO2 storage and the development of agriculture and aquaculture. The limited accessibility of the coastal zone and the challenge to demarcate mudbanks in satellite observations make it difficult to differentiate between natural changes and those caused by mudbank migration, human interference or the impact of climate (change). Satellite observations offer the potential to improve future predictions, accurately analyse indicators of changes in mangrove forests and timely detect coastline changes on local- to regional scales. In this thesis a remote-sensing workflow was developed to utilize the spatial and temporal resolution of the complete Landsat satellite data archive since 1986 for the detection of mudbanks and associated coastal changes. This information was used to quantify the effect of mudbanks on local scale for the purpose of coastal management. We show that on average 32 m/yr coastal expansion occurs when mudbanks are present and 4 m/yr of erosion when absent. Large spatial- and temporal variations however highlights the importance variable mudbank footprints, caused by currents and waves, for the duration of coastal protection and natural changes that occur in mangrove forests.

Although tropical forests are rich in plant diversity and deliver essential ecosystem services, goods and services that benefit our well-being, tropical forests are under increasing pressure of deforestation and degradation. In response and under the assumption that biodiversity and ecosystem services are positively related, conservation measures are increasingly focussing on ecosystem services. Yet, for tropical forests, such relationships remain unclear. This thesis identified three important knowledge gaps. First, it is unclear how plant diversity in a broad sense (including taxonomic, functional and structural diversity) is related to the stock and the flow components of ecosystem services. Second, questions have been raised on how using a different plot size or geographical extent can affect relationships. Third and last, it is unknown how the combination of ecological factors and socio-economic factors can influence relationships. To close these knowledge gaps, this thesis explored the relationships between plant diversity, carbon storage, timber provisioning and the provisioning of non-timber forest products (‘NTFPs’; products such as medicines, food and cultural totems) in old-growth tropical forests. As there were many potential relationships to consider, this thesis aimed to “see the forest through the trees” and to come to general implications for tropical forest conservation. A systematic review of pan-tropical studies found mainly positive relationships between plant diversity in a broad sense and carbon storage, regardless of the stock or flow. By contrast, relationships concerning timber and NTFPs had been poorly studied. Although the reported positive relationships were in line with predictions, the discovered mix of positive and negative relationships was surprising. Plot size was found to moderate relationships, where relationships were more often significant when smaller plots were used. Direct analyses of the relationships between woody species richness and the stock component of the three ecosystem services within and across Amazonia showed that woody species richness was consistently positively related to carbon stock. This thesis provides evidence suggesting that previously reported zero to negative outcomes for this relationship were due to moderating effects of sampling a large amount of environmental heterogeneity by including a large geographical extent. The found positive relationship suggests that protecting carbon-rich tropical forests in the Amazon is likely to protect concentrations in woody species diversity as well. By contrast, timber stock and NTFP stock were not consistently related to woody species richness in the Guiana Shield, a region of Amazonia. Instead, these stocks were related to differences in floristic composition across forest types and biogeographical subregions. In Suriname, a country on the Guiana Shield, NTFP stocks were mainly determined by a very small number of woody species called ‘NTFP oligarchs’, which were associated to specific floristic compositions. However, NTFP flows were ultimately determined by socio-economic factors such as the demand, costs and harvest rules. These factors determined which NTFP stocks were harvested, regardless of how much stock or plant diversity was present. These findings suggests that forests with important timber and NTFP stocks will often be located near forest-dwelling communities. Therefore, protection of these stocks could benefit from allowing community management of forests.

Transformative changes in societal systems are needed to halt ongoing ecosystem degradation and biodiversity loss. Particularly in natural resource-intensive sectors, such as agriculture, forestry and mining, such shifts are essential as these sectors contribute substantially to biodiversity loss. At the same time, these sectors could also play a central role in the required shifts towards sustainability, if the associated production and consumption patterns are altered. The aim of this thesis is to better understand transformations towards biodiversity conservation in these sectors, by studying processes and factors that stimulate or hinder change. Transformations towards sustainability within these sectors are highly complex. On the one hand, it requires major changes in the landscape itself to conserve biodiversity, through new collaborations, institutions and different management practices. On the other hand, different organization of value chains and new business models are needed, as changes in the local landscape are strongly externally driven by global value chains, markets and policies. To understand change on these various levels, this thesis uses and combines various theoretical perspectives: (1) sustainability transitions, (2) socio-ecological systems and landscape approaches, and (3) sustainable business models. Various cases are studied, including the transition towards nature-inclusive agriculture in the Dutch dairy sector, and the circular economy in the Netherlands.

The relatively undisturbed tropical forest regions offer unique opportunities to mitigate climate change and the loss of biodiversity. The global importance of their management by indigenous and tribal communities for the conservation is widely understood. Despite this, the rapid expansion of external pressures (e.g. logging, agri-business, mining and infrastructure) far into these lands, with various consequences for local livelihoods, is challenging the ability of local communities to sustainably manage these lands. It is therefore urgent to involve them in the land use decision making that affects them, as well as to consider the entangled social and ecological transformation processes that they undergo upon the arrival of external pressures. However, tools and approaches that enable their engagement are not yet sufficiently available. Moreover, our scientific understanding of how external pressures affect the spatial and temporal dynamics of ecosystem service use by local communities and how these dynamics affect the conservation of intact forest areas is still limited. This doctoral thesis addresses this pressing gap through spatial knowledge co-production involving 1108 indigenous and tribal community members from three intact forest regions, one in the Colombian Amazon and two in Suriname. Two main conclusions stem from this doctoral thesis. First, that co-produced spatial knowledge is useful to understand the patterns of ecosystem service use by indigenous and tribal communities in intact forest regions and to respond to complex and multiple realities in the field. Second, practical application of the results of this thesis suggests that the engagement of an inspired local champion and broker is a crucial factor to foster the usability of co-produced spatial knowledge in land use decision-making. This doctoral thesis in particular contributes to filling the current deficit of local spatial knowledge in regional and global scenarios of land use planning in intact forest regions, as highlighted in the latest IPBES Global Assessment Report of ecosystems and biodiversity.

Developing agricultural systems that produce food and income to sustain smallholder livelihoods in the tropics, without further compromising ecosystem functioning and biodiversity conservation, is an important societal challenge. Agroforestry systems pose a promising approach to deal with the twin challenges of local development and conservation of ecosystem services like biodiversity. But while the ecological benefits of these systems are clear, they are still believed to underperform economically, compared to intensified conventional systems. More insight in the relations between crop productivity, biodiversity and smallholder livelihoods is needed to identify systems that can minimise trade-offs between economic and environmental performance or even provide double dividends. This thesis therefore aims to i) assess the economic and environmental outcomes of smallholder management systems to identify trade-offs and seek opportunities for double dividends, and ii) identify opportunities and constraints for smallholder farmers to adopt associated management strategies. Due to their economic and ecological importance worldwide, this thesis focuses on coffee and cocoa smallholder systems; with in-depth empirical case study on smallholder coffee systems in San Martín, Peru. This thesis shows that contrary to popular belief, agroforestry systems can offer competitive business opportunities in comparison to the expanding, conventionally intensified systems and can reconcile farmer livelihoods and conservation of biodiversity and other ecosystem services. First of all, no trade-offs were found between coffee yields, forest butterfly species richness and above-ground carbon storage and shaded coffee systems supported biodiversity and carbon storage. Importantly, no evidence for a negative relation between coffee yields and shade was found across a shade cover range of 0-80%. Secondly, this thesis provides evidence that systems with high shade levels can perform equally well or better compared to plantations with lower shade levels and/or with higher input levels. There were no differences between net income and benefit-cost ratio (BCR) for plantations with different shade management practices. Rather, net income and BCR were lower for plantations with higher input practices. This was explained to some extent by higher costs of intensified systems, both for flexible (inputs and labour) and fixed costs (land and equipment), while costs were lower for plantations with higher shade levels. Third, there were no trade-offs between butterfly diversity and above-ground carbon storage with net income for this case study of Peruvian coffee farmers. Lastly, the results suggest that improving livelihood assets is important for decision making, and the actionable assets differ for shade and input management; whilst human, social and natural assets may limit or enhance adoption of environmentally-friendly management systems, financial and physical assets may affect adoption of input management strategies. Importantly, it became clear that the benefits of agroforestry systems are very diverse and location-specific and that there is no blueprint for management systems that will provide double dividends under all circumstances. In order to reconcile economic and ecological goals in coffee and cocoa systems, comprehensive multidisciplinary analyses are needed, including for other regions, to be able to draw generalizable conclusions and deepen our insight in trade-offs between economic and environmental performance.

Agroforestry systems provide multiple ecosystem services and are refuges for diverse flora and fauna. Coffee is one of the main tropical agroforestry crops and of global economic importance. Over recent decades, coffee agroforestry systems have been increasingly intensified by the replacement of native shade tree diversity with one or few, often non-native, tree species. Such reduction in tree diversity might have implications for ecosystem services, such as nutrient cycling, soil fertility, pest control, and coffee production, and ultimately negative effects for the systems’ resilience to climate change. The overall aim of this thesis is to investigate the direct and indirect effects of tree diversity reduction on ecosystem services, to understand the arising management trade-offs for Coffea canephora production in the face of climate change. We therefore studied 25 agroforestry systems in Kodagu, India, across a broad rainfall and management gradient, which experience a gradual transformation of native diverse shade tree canopy to Grevillea robusta dominated shade. Climate change is expected to alter the intense monsoon rainfalls during the short, wet season by an increase in the east and a reduction in the west. The results show that the transformation towards G. robusta dominated shade has not only highly negative effects for tree diversity but also for coffee production and quality. Both coffee production and quality were lower under G. robusta dominating shade. This resulted mainly from the increased development of single-seeded fruits (pea-beans), likely a result from reduced pollination success, and higher infestation rates of the coffee berry borer, Hypothenemus hampei. This suggests that pest control and pollination services are reduced in monospecific agroforestry systems. Grevillea robusta shade reduced nutrient cycling and long-term soil fertility. In contrast to native trees, G. robusta leaf litter shedding was more dependent on the annual rainfall, which reduced litterfall in wet sites to negligible amounts. Low litter quality and reduced decomposition rates characterize G. robusta dominated agroforests, and this led to low soil fertility and a decline in soil carbon contents, particularly in wet sites. The specific characteristic of G. robusta, being a Proteaceae, reduced phosphor cycling by increasing the immobilization of the same. Although, we did not find evidence for increased nutrient limitation in C. canephora leaves under G. robusta shade, the loss of soil carbon reduces soil fertility and nutrient availability over the long-term, which will likely demand higher nutrient inputs in the future. Microclimate and soil moisture was negatively altered under G. robusta monospecific shade compared to native diverse agroforests. Low soil carbon was one of the main drivers for lower soil moisture under G. robusta, which increased nutrient leaching. This, together with higher relative air humidity, reduced coffee production in monospecific shade. While high monsoon rainfall reduced coffee production in all agroforestry types, throughfall reduction benefitted coffee plants less under G. robusta dominated shade, in which high nutrient leaching resulted in a lower final berry-set. In conclusion, we provide strong evidence that there are no trade-offs, but synergies between tree diversity, coffee production and resilience to climate change. A shade cover dominated by G. robusta affects ecosystem resilience by causing: (1) increased pest attacks likely due to a loss of complex multi-trophic interactions; (2) reduced nutrient cycling and loss of soil carbon, reducing soil fertility in the long-term; (3) reduction of soil moisture and increase of nutrient leaching likely via runoff; (4) increased relative humidity potentially due to higher transpiration of the fast-growing G. robusta. These characteristics of G. robusta dominance negatively affect coffee production and quality, and reduce the agroforestry systems’ resilience to climate change.

The production of commodities such as palm oil and pulpwood is leading to large-scale land use change in the rural tropics to fulfil the demands of the increasing world population and overall living standard. On the one hand, such land use changes provide income to companies, smallholders and government actors. On the other hand, these can lead to land use conflicts and declines in forest cover, biodiversity, carbon stocks, and local food production. In this dissertation, firstly, we quantified and visualised land use change processes and trajectories that contributed to forest loss in the West Kutai and Mahakam Ulu districts between 1990 and 2009. These districts are part of a landscape that is under high land development pressure in East Kalimantan, Indonesian Borneo. Over the time period analysed, about one third of the study area changed and forest cover declined substantially with almost 10 %. The main contributors to forest loss included smallholder rubber, pulpwood plantations, mixed cropland and oil palm, the latter with a rapidly increasing land area. Secondly, we projected and visualised the impacts of four contrasting land use change scenarios with varying levels of land development and restrictions of land zoning on forest cover in these districts between 2009 and 2030. We found that with unlimited development of the aforementioned commodities, forest cover declines substantially stronger (~0.4-1.6 Mha, ~17-60%) than with limited development (~ 0.1 Mha, ~4%). Thirdly, we estimated the impacts of the four scenarios on plant biodiversity and carbon. We found that between 1990 and 2030, mean species richness declined much stronger (-22% to -52%) than AGB (-19% to -37%). Under all scenarios, the lowlands showed the highest risk of land use change. Fourth, we analysed whether and how the production of palm oil can be reconciled with the production of pulpwood, rice and rubber, while mitigating unwanted land use changes. We analysed the technical potential of four measures to mitigate unwanted land use change between 2008 and 2020 in North and East Kalimantan. We found that the expansion on under-utilised land is the most important measure (45-62% of total potential), followed by improvements in yields (32-46%), chain efficiencies and chain integration. Finally, we discussed the findings of the previous chapters in the context of the Forest Transition Theory. We estimate that our study region is only at the start of the forest transition curve, possibly in stage 2, given the high forest cover and high deforestation rates. We estimate that a stabilising forest cover in the study region is possible, but only with an integrated perspective on mitigating unwanted land use change that includes significant efforts in i) establishing a limit-to-growth on land development for the production of palm oil, rubber, pulpwood and coal; ii) responsible land use planning and zoning, by using underutilised lands and accounting for land tenure; iii) developing or strengthening incentives to maintain forests, such as Reducing Emissions from Deforestation and forest Degradation+; iv) implementing additional measures, such as yield improvements; v) supporting these measures by capacity building and enabling policies.

Human impact on nature has been severe in the past centuries. Land use change is seen as the main driver of the loss of biodiversity worldwide. Conversion of natural ecosystems into agricultural land or urban areas has led to habitat loss and degradation for many plant species. Additionally, land use change typically results in a fragmented distribution of the remaining habitat. Habitat fragmentation may result in increased extinction risk of local populations of plant species, by a decreased local population size, increased edge:area ratio and increased isolation between local populations. To ensure connectivity between fragmented local populations, effective seed dispersal is of vital importance. Knowledge on dispersal capacity of plant species in fragmented habitats differing in spatial configuration is thus important for understanding (meta)population dynamics and for spatial optimisation of restoration measures. Although many studies have shown the importance of seed dispersal via surface water (hydrochory) for plant population and community patterns, and thus for biodiversity, the precise mechanisms determining hydrochorous dispersal capacity of plant seeds in different fragmented landscapes are underexposed in the literature. The aim of this thesis was to shed light on the contribution of hydrochory to seed dispersal in fragmented freshwater wetlands impacted by human activity, with special attention for the effect of landscape configuration and characteristics of the water body on realised dispersal distances. For this purpose an innovative combination of different research approaches including fieldwork, analyses of large datasets, experimental research and model development and simulations was used. The results showed that habitat fragmentation per se indeed has negative effects on species occurrence in freshwater wetlands. Therefore, it is important not only to improve habitat quality but also to consider spatial characteristics of the habitat of target species when deciding on plant conservation strategies in intensively used landscapes, such as fen areas in Western Europe and North America. Results of the seed dispersal experiments showed that unlike in rivers, seed transport in ditches was determined by wind speed and direction in stead of by water flow, enabling multidirectional seed dispersal. Model results showed that density or direction of the ditch network did not seem to influence simulated water dispersal distances substantially, whereas roughness of the ditch and obstructions in the ditch strongly limited seed dispersal distances. Hydrochorous dispersal contributed considerably to the total simulated dispersal of wetland plant seeds across agricultural landscapes, for both wind and water dispersal specialists. In contrast, simulated wind dispersal distances were nil for water dispersal specialists. Also for wind dispersal specialists, wind dispersal distances were limited. These results suggest that in a modern agricultural landscape with a network of ditches, water is an important dispersal vector for both typical wind and typical water dispersers. The importance of hydrochorous dispersal for connectivity within metapopulations of riparian species in a fragmented landscape may be greater than the importance of wind dispersal. Hence, improving the infrastructure of linear aquatic systems for hydrochrorous seeds could increase metapopulation viability of riparian species, wetland biodiversity, and the success of wetland restoration projects.

Nicaragua és un país on la generació d'electricitat a partir de biomassa és una alternativa interessant per a reduir el consum de combustibles derivats del petroli. En els últims anys, entre un 70 i 81% de l'electricitat s'ha generat a partir de derivats de petroli (Fuel Oil o Gasoli). Amb la pujada dels preus del petroli el país ha de dedicar gran part dels seus recursos econòmics per a la importació d'aquests combustibles. Per a trobar una sortida a l'enorme dependència energètica, cal investigar una font d'energia que sigui renovable i que tingui efectes positius des del punt de vista econòmic, social i ambiental. La utilització dels residus agrícoles, forestals i la biomassa que es pot obtenir de plantacions forestals energètiques és una alternativa interessant. No obstant això, la planificació de localitzacions i les grandàries òptimes de les plantes generadores requereixen un procés complex comparat amb generadores que utilitzen combustibles fòssils. Per tant l'objectiu d'aquest estudi és desenvolupar un model espacial per a estimar la disponibilitat potencial de biomassa a Nicaragua.La metodologia ha consistit de dues fases, primer a una escala nacional s'ha fet una zonificació agroecológica i s'han seleccionat ubicacions favorables per a les plantes generadores. En la segona fase, les àrees seleccionades són objecte d'un estudi més detallat i mitjançant un procés d'optimització entre la demanda i el subministrament de biomassa es determina la grandària de les plantes. Addicionalment es prenen en compte aspectes ecològics i socioeconòmics.En ambdues fases, el procés parteix de la recopilació de dades per a conformar una base de dades cartogràfica desenvolupada en un SIG. S'efectua una zonificació agroecológica i s'estimen els rendiments potencials amb el mètode ZAE (Kassam, 1977), posteriorment es calculen els rendiments limitats per aigua a través del mètode CROPWAT i els resultats són confrontats amb dades de terreny i dades d'experts per a estimar el rendiment agronómicamente assolible. L'optimització econòmica i energètica es fa sobre la base del balanç d'oferta i demanda i els costos de producció i transport de la biomassa.Els resultats obtinguts ens indiquen que a Nicaragua hi ha suficient biomassa per a ser utilitzada amb fins energètics. D'acord a la zonificació agroecológica, el 47% del territori té un potencial forestal, i el model espacial desenvolupat estima en 62 milions de Mg de biomassa en aquesta àrea. A això li podem agregar 644 mil Mg de residus amb valor energètic que prové de cultius agrícoles. Si s'utilitzéssin solament els residus agrícoles, es generarien 64 MW a l'any. Les zones amb major potencial per a produir biomassa amb finalitats energètiques són la part nord oriental del país (entri Bilwi i el triangle miner), el centre (entri Waslala i Siuna) i la regió centre oriental (Muelle de los Bueyes). Per la seva ubicació i condicions contrastants es van seleccionar tres llocs per a realitzar els estudis de cas: Wasakin, Sébaco i Tipitapa.L'anàlisi detallada dels llocs seleccionats ens indica que a Tipitapa hi ha potencial per a generar electricitat en una planta de 37 MW, considerant la biomassa disponible en un radi de 25 km d'acord a l'optimització econòmica i energètica. L'altre lloc, Sébaco, on es concentren gran quantitat de residus com pellofa d'arròs i clofolla de cafè té un potencial de 35 MW. Finalment, Wasakin, considerant només l'àrea concesionada per a una empresa forestal i utilitzant únicament els residus forestals generats es va estimar un potencial de 1.37 MW que provenen de les activitats de tallada i processament de la fusta en una àrea de 9 mil ha. Malgrat això, hi ha limitacions de tipus tècnic i econòmic per a construir-hi una central de producció de biomassa.La combinació del mètode ZAE i el model CROPWAT, aplicats per mitjà d'un SIG proporciona resultats molt aproximats al terreny i permeten modelizar diferents escenaris per al suport en la presa de decisions., Nicaragua es un país en donde la generación de electricidad a partir de biomasa ha probado ser una alternativa interesante para reducir el consumo de combustibles derivados del petróleo. Pero en los últimos años, entre un 70 a 81% de la electricidad se ha venido generando con derivados de petróleo (Fuel Oil o Gasoil). Con la subida de los precios del petróleo el país tiene que dedicar gran parte de sus recursos económicos para la importación de estos combustibles. Para encontrar una salida a la enorme dependencia energética, es necesario investigar una fuente de energía que sea renovable y que tenga efectos positivos desde el punto de vista económico, social y ambiental. La utilización de los residuos agrícolas, forestales y la biomasa que se puede obtener de plantaciones forestales energéticas es una alternativa interesante. La planificación de localizaciones y los tamaños óptimos de las plantas generadoras requieren un proceso complejo comparado con generadoras que utilizan combustibles fósiles. Por lo tanto el objetivo de este estudio es desarrollar un modelo espacial para estimar la disponibilidad potencial de biomasa en Nicaragua.La metodología ha consistido de dos fases. primero, a escala nacional se ha realizado una zonificación agroecológica y se han seleccionado ubicaciones favorables para las plantas generadoras. En la segunda fase, las áreas seleccionadas han sido objeto de un estudio más detallado y mediante un proceso de optimización entre la demanda y el suministro de biomasa se ha determinado el tamaño de las plantas. Adicionalmente se han tomado en cuenta aspectos ecológicos y socioeconómicos.En ambas fases, el proceso parte de la recopilación de datos para conformar una base de datos cartográfica desarrollada en un SIG, se efectúa una zonificación agroecológica y se estiman los rendimientos potenciales con el método ZAE (Kassam, 1977). Posteriormente se calculan los rendimientos limitados por agua a través del método CROPWAT y los resultados son confrontados con datos de terreno y datos de expertos para estimar el rendimiento agronómicamente alcanzable. La optimización económica y energética se hace en base al balance de oferta y demanda y los costos de producción y transporte de la biomasa.Los resultados obtenidos nos indican que en Nicaragua hay suficiente biomasa para ser utilizada con fines energéticos. De acuerdo a la zonificación agroecológica, el 47% del territorio tiene un potencial forestal y el modelo espacial desarrollado estima en 62 millones de Mg de biomasa en esta área. A esto le podemos agregar 644 mil Mg de residuos con valor energético que proviene de cultivos agrícolas. Si se utilizaran solamente los residuos agrícolas, se generarían 64 MW al año. Las zonas con mayor potencial para producir biomasa con fines energéticos son la parte norte oriental del país (entre Bilwi y el triángulo minero), el centro (entre Waslala y Siuna) y la región centro oriental (Muelle de los Bueyes). Por su ubicación, y condiciones contrastantes se han seleccionado tres sitios para realizar los estudios de caso: Wasakin, Sébaco y Tipitapa.El análisis detallado de los sitios seleccionados nos indica que en Tipitapa hay potencial para generar electricidad en una planta de 37 MW, tomando en cuenta la biomasa disponible en un radio de 25 km de acuerdo a la optimización económica y energética. El otro sitio, Sébaco, donde se concentran gran cantidad de residuos como cascarilla de arroz y cascabillo de café tiene un potencial de 35 MW. Por último, Wasakin, considerando solamente el área concesionada para una empresa forestal y utilizando únicamente los residuos forestales generados se ha estimado un potencial de 1.37 MW que provienen de las actividades de corte y procesamiento de la madera en una área de 9 mil ha. Sin embargo, hay limitaciones técnicas y económicas para poder construir en este sitio una planta de generación a partir de biomasa.La combinación del método ZAE y el modelo CROPWAT, aplicado por medio de un SIG brinda resultados muy aproximados al terreno y permiten modelizar distintos escenarios para el apoyo en la toma de decisiones., Nicaragua is a country where the electricity generation from biomass has proven to be an interesting alternative to reduce the consumption of derived fuels of the petroleum. Nevertheless, in the last years, between a 70 to 81% of the electricity came from petroleum products (Fuel Oil or Gasoil). With increasing fuel prices the country has to dedicate great part of its economic resources for the import of these fuels. In order to look for a solution from this enormous energy dependence, it is necessary to find another energy source that can be renewable and with positive effects from the economic, social and environmental points of view. The use of the agricultural, forest residues and the biomass that can be obtained of forest energy plantations is an interesting alternative. However, the planning of localizations and the good sizes of the generating plants require a complex process compared with those using fossil fuels. Therefore the objective of this study is to develop a spacial model to estimate the potential biomass production for energy in Nicaragua.The methodology consisted of two phases. First, at a national scale an agroecological zonning was made, and favorable locations were selected for the generating plants. In the second phase, the selected areas were object of a detailed study and by means of a process of optimization between the demand and the supply of biomass the size of the plants was determined. Additionally, the ecological and socioeconomic aspects were taken into account.In both phases, the process takes input data to conform a cartographic database developed in a SIG. An agro ecologic zoning is made and the potential yields with the method AEZ (Kassam, 1977) are obtained. Later on the water-limited yields are calculated through the CROPWAT method and the results are confronted with land data and experts' data to estimate the attainable agronomical.yield. The economic and energetic optimization is made based on the balance between offer and demand and the production costs and transport of the biomass.The obtained results indicate us that in Nicaragua there is enough biomass to be used for energetic purposes. According to the agro ecologic zoning, 47% of the territory has a forest potential and the model developed assessed 62 millions of Mg of biomass in this area. Moreover we can add it 644 thousand Mg of residues with energy value that comes from agricultural cultivations. If only the agricultural residues were used, 64 MW a year would be generated. The areas with more potential to produce biomass with energetic value are the oriental north part of the country (between Bilwi and the mining triangle), the center (between Waslala y Siuna) and the eastern center region (Muelle de los Bueyes). According to their location and contrasting conditions three places were selected to carry out the case studies: Wasakin, Sébaco and Tipitapa.The detailed analysis of the selected places indicates that in Tipitapa there is potential to generate electricity in a power plant of 37 MW, taking into account the available biomass in a radius of 25 km according to the economic and energetic optimization. The second place, Sébaco, where great quantity of residues like husk of rice and coffee parchment are produced, has a potential of 35 MW. Finally, Wasakin, considering only the area under concession for a forest company and using the generated forest residues had only a potential of 1.37 MW that came from the activities and processing of the wood in an area of 9000 ha. Nevertheless, there are technical and economic limitations for building and implementing an energy central in this site.The combination of the AEZ method and the CROPWAT frame, applied by means of a GIS offers very approximate results to the field data and allow modeling of different scenarios for decision support.