Biomass Flow Research Articles

Modeling Trophic Cascades to Identify Key Mammalian Species for Ecosystem Stability

The role of keystone species in maintaining ecosystem stability is a crucial aspect of ecology. Identifying key mammalian species within an ecosystem requires a systematic approach, utilizing criteria and indicators derived from species characteristic variables. This study presents a framework to identify key mammalian species based on various ecological, structural, and functional factors. By developing a mechanistic model of energy flow in food webs and trophic levels, the model aims to pinpoint each species’ role in the stability and sustainability of biomass flow within the ecosystem. Known as KVT version 1.0, the model explains the role of each characteristic variable of mammalian species, predicts population growth, elucidates species interactions at trophic levels, and assesses species-specific dietary compositions, including food requirements, reproduction, and activity. Factor analysis of model outputs has produced equations to determine the value of keystone species (Kv), indicating the role of mammalian species in the stability and sustainability of biomass flow in the ecosystem. Keystone species, as identified by this model, are primarily small mammals of the families Muridae, Sciuridae, Tupaiidae, Ptilocercidae, Hystricidae, Viverridae, and Herpestidae, demonstrating omnivorous and herbivorous trophic levels. This model can serve as a valuable framework for conservation management of biodiversity in an ecosystem, with potential for expansion to include characteristics of non-mammalian species in future research.

Resolving complexity: Material flow analysis of a national wood flow system integrating the versatility of wood

AbstractA systemic understanding of the use of wood resources is required to defossilize society and promote bio‐based developments. This study provides a novel approach to represent a comprehensive material flow analysis (MFA) spanning the entire wood value chain; encompassing wood harvest to products, use in society, collection, reuse, recycle, energy generation, and trade. By recognizing wood as a complex material, with changing properties throughout its lifespan, we developed a method where we employed a color‐coded system for processes (27 boxes) and 110 flows to symbolize distinct life stages and the dynamic characteristics, including 23 different trade flows. The wood processes and flows are categorized (11 categories) into different wood types (e.g., softwood and hardwood) and harmonized to include all available data on each single step of the wood life cycle, improving data traceability and visualization, and allowing for replicable analysis with respective data noted for each process and flow. Methodological obstacles due to different units, uncertainty of flows, and discrepancies in data are addressed and adjustments proposed. Switzerland was chosen as a case study as a large number of various types of data were available to perform the analysis. The categorized and harmonized flows of woody biomass mapped and analyzed in the MFA provide a comprehensive basis to identify and recommend avenues to increase cascading use of wood as a carbon sink, by considering relevant aspects like the network of flows and processes, the quality and availability of the woody biomass, and the organization of the industry.

Characteristics of Biochar Obtained by Pyrolysis of Residual Forest Biomass at Different Process Scales

In this work, the pyrolysis process and the characteristics of biochar produced using a bench-scale fixed-bed reactor and a prototype-scale auger reactor were studied. Residual forest biomass (RFB) from acacia, broom, gorse, and giant reed was used as feedstock. Besides information on pyrolysis characteristics of these specific biomass species from the Iberian Peninsula, new knowledge on the understanding of how results from small-scale reactors can be used to predict the behavior of higher-scale and continuous-operation reactors is offered. Batch pyrolysis was carried out using 40 g of biomass sample in a fixed-bed reactor with a heating rate of 20 °C∙min−1, pyrolysis temperature of 450 and 550 °C, and a residence time of 30 min, while for the continuous process it was used a prototype of an auger reactor with continuous operation with a biomass flow rate up to 1 kg/h, with temperatures of 450 and 550 °C, and a solids residence time of 5 min. The biochar yield was in the range of 0.26 to 0.36 kg/kg biomass dry basis, being similar for both types of reactors and slightly lower when using the auger reactor. The proximate analysis of the biochar shows volatile matter in the range 0.10 to 0.27 kg/kg biochar dry basis, fixed carbon in the range 0.65 to 0.84 kg/kg biochar dry basis, and ash in the range 0.04 to 0.08 kg/kg biochar dry basis. The carbon, oxygen, and hydrogen content of the biochar was in the range of 0.71 to 0.81, 0.09 to 0.22, and 0.02 to 0.03 kg/kg biochar dry basis, respectively. The results show that the up-scaling of the reactor and regime of operation does not have an important influence on the yield and characteristics of the biochar produced. The biochar obtained in the two types of reactors has characteristics appropriate for environmental applications, such as an additive to improve soil properties. It is possible to see that the characteristics of the biochar are influenced by the type of biomass and the conditions and parameters of the process; therefore, it is of major importance to control and know of these conditions, especially when considering upscaling scenarios.

A case study of the regional bioeconomy in Central Germany: construction with renewable resources

In response to global challenges like climate change and resource depletion, national and international policies are increasingly emphasising sustainability. The bioeconomy represents a promising field to reconcile environmental integrity with economic development. The objective of this study is to examine the role of renewable resources in the construction industry within the framework of the bioeconomy, with a particular focus on Sustainable Development Goal 11: ‘Sustainable cities and communities’. The case study analyses the practical challenges and opportunities for innovation in Central Germany through a comprehensive regional analysis of construction practices using renewable resources. The methodology involved monitoring biomass flows by assessing harvest yields, area shares and biomass potentials. It also analysed the importance of the bio-based economy by examining employment data and identifying potential growth sectors. Stakeholder engagement was facilitated through knowledge transfer workshops to encourage collaboration and innovation. The results of the study highlight key trends within the industry, including the increasing prevalence of timber buildings, wood as a renewable carbon source in the chemical industry and the growing demand for wood-based packaging solutions. Policy initiatives are playing a supportive role in driving these developments, taking advantage of the region’s extensive wood resources (14.7 million m3 harvested in 2021) and the significant employment contribution of the forestry, wood and construction industries (2% of total employment, representing no less than 81,506 employees). These figures demonstrate the potential for sustainable construction practices to drive local economic growth and contribute to wider environmental objectives.

Graph-theoretic modeling reveals connectivity hotspots for herbivorous reef fishes in a restored tropical island system

ContextSeascape connectivity refers to how the spatial configuration of marine habitats facilitates or hinders the movement of organisms, nutrients, materials or energy. Predicting and ranking potential connectivity among habitat patches for coral reef fishes helps to understand how reef fishes could utilize and connect multiple habitat types through the flow of nutrients, energy and biomass across the wider seascape during foraging movements.ObjectivesTo advance a spatially explicit understanding of connectivity linkages within a tropical atoll system by modeling, mapping and quantifying potential seascape connectivity for two locally abundant herbivorous reef fish species, the parrotfish, Chlorurus spilurus (pahoro hohoni or pa’ati pa’apa’a auahi), and the surgeonfish, Acanthurus triostegus (manini).MethodsWe applied a two-step modeling approach by first mapping habitat suitability for the focal species. A graph-theoretic modeling technique was then applied to model and measure the contribution of benthic habitat patches to species-specific potential connectivity within the seascape.ResultsHabitat suitability was higher and less fragmented for C. spilurus than for A. triostegus. Potential ecological connectivity estimates for C. spilurus were higher across the entire seascape, with differences between species likely driven by local-scale benthic habitat patch configuration and species home ranges. Hotspots of ecological connectivity across the atoll were mapped for both species.ConclusionsDespite advances in the application of graph-theoretic techniques in the coastal environment, few marine conservation and restoration measures currently integrate spatial information on ecological connectivity. This two-step spatial modeling approach holds great potential for rapid application of connectivity modeling at multiple spatial scales, which may predict ecological responses to conservation actions including active habitat restoration.

Towards a Territorial and Political Ecology of “circular bioeconomy”: a 30-year review of metabolism studies

Abstract In the context of the increasingly present policies of circular economy and the emergence of “Circular Bioeconomy” (CB), this article presents the results of a literature review on the sociometabolic research of biomasses. Six schools of thought are identified and distinguished according to their authors, their conceptions of metabolism, methodologies and social and spatial dimensions. Based on this state of the art, we propose an analytical framework that combines quantitative and qualitative approaches at the territorial scale, drawing upon the currents of Territorial Ecology and Political Ecology. This framework enhances our understanding and provides a critical perspective on the geography of CB. We compare discourses to actual practices by analysing biomass flows and power relations while adopting a critical perspective toward circular economy policies.

Factors driving microbial biomass and necromass relationships display ecosystem‐dependent responses

AbstractMicroorganisms help govern soil organic carbon (SOC) turnover and accumulation. Whilst it is increasingly clear that microbial necromass is a precursor of SOC formation, the relationship between living microorganisms, necromass turnover and SOC persistence remains elusive. In this study, we used phospholipid fatty acids and amino sugars to quantify living versus dead microbial carbon concentrations and evaluated the utility of each pool as an indicator of SOC persistence across a range of climates (low‐, mid‐ and high‐latitude sites) and ecotypes (old‐growth forests vs. managed croplands). We found that microbial necromass was higher in forest than in cropland soils and was positively correlated with soil moisture, SOC and total nitrogen (TN). However, the flow of microbial biomass into necromass and SOC was decoupled in forest sites, likely because the high soil SOC/TN ratio accelerated necromass turnover and recycling by living microorganisms. In contrast, microbial biomass and necromass pools were tightly coupled in croplands and influenced by multiple environmental and biological factors (e.g., necromass concentrations exhibited greater variability in soils with more bacteria than fungi, and those with more gram‐positive than gram‐negative taxa). Contrasting our expectations, the proportion of microbially‐derived necromass in SOC was decoupled from soil properties and microbial biomass in both ecotypes. Whilst SOC and pH appear to be universal drivers of necromass cycling, feedbacks between living biomass, necromass and SOC are shaped by local factors. Our results contribute to ecological theory by highlighting the environmental and biological factors underpinning SOC formation and turnover that can be used to inform land‐management practices that optimize below‐ground carbon sequestration.

Modeling of a Biomass Cogeneration Plant from a Gasification Process

In recent decades, growing energy demand, coupled with concerns about climate change, has led to the exploration of sustainable energy sources. Among these, biomass gasification stands out as a promising method for generating heat and power. This research delves into the potential impact of biomass gasification within the global energy landscape, focusing particularly on its application in cogeneration plants. Utilizing Aspen Plus software V10, this study undertook the modeling and optimization of a biomass cogeneration plant. Through simulation, it was found that a biomass flow rate of 5 kg/s yielded 6.172 MW of power output. Additionally, the study revealed several key factors that influence power generation: increasing biomass and airflow rates, increasing gasification temperature, and reducing water flow rate. By doubling the biomass flow rate to 10 kg/s and increasing the temperature to 800 °C, power generation increases by 41.75%. Moreover, the study demonstrates that Portuguese municipal waste is an efficient source of energy production, with higher cold gas and overall efficiencies compared to forest and vine-pruning residues.

Biomass and nutrient flow dynamics and sustainability practices to de-risk environmental challenges in the sub-saharan Africa farming system

In sub-Saharan Africa, productivity risks stem from weather variability, while environmental risks include soil nutrient depletion due to unsustainable farming practices that include monoculture, inadequate or lack of soil and water conservation measures, and low-nutrient application. As a result, shifts from the prevailing fallow system to permanent cultivation lead to soil degradation. The present study aimed to quantify the fluxes of biomass, nutrients, and nutrient balances from different fertilizer sources to de-risk the challenges related to agriculture and the environment in Mali. A farm household survey was conducted over two years (July 2018 to June 2020) with 45 households. The survey enabled us to categorize farm households into three typologies: high resource endowment (HRE), medium resource endowment (MRE), and low resource endowment (LRE). Data on sustainability indicators from cropland, livestock, farm input use, and redistribution units enabled the analysis of biomass and nutrient flow dynamics from households to farmlands and vice versa. The nutrient monitoring (NUTMON) tool generated nutrient flows and balances. Results showed that the total annual biomass collected per hectare by HRE (22.3t) is significantly higher than that collected by MRE (13.4t) and LRE (5.35t) farms (P ​< ​0.001). Compared to LRE (10.3 ​t ​ha−1 year−1), HRE and MRE farmers produced six times (60 ​t ​ha−1 year−1) and three times (34 ​t ​ha−1 year−1) more manure, respectively. Farm households with better endowment status observed a higher rate of nutrient utilization. For the major crops, nutrient application rates of HRE farms in kg ha−1 (cotton: 12.6 ​N, 4.2 ​P, 18.2 ​K) and (maize: 9.18 ​N, 2.34 ​P, 10.7 ​K) were significantly higher than that of MRE and LRE farms (P ​< ​0.01). The study confirms that household endowment status determines farmlands' nutrient flows and fertility levels. Quantifying biomass transport and understanding nutrient flow dynamics enable the derivation of context-specific solutions to reduce risks associated with productivity and the environment.

Experimental assessment of oxy-CO2 gasification strategy with woody biomass

This paper presents the results obtained during an extensive experimental campaign focused on analysing the application of Oxy-CO2 gasification technology to a small downdraft gasifier fed with woody biomass. Oxy-gasification enables the production of a nitrogen-free synthesis gas (syngas), which can be effectively employed in the synthesis of various high-value chemicals, including but not limited to synthetic natural gas (SNG), methanol (CH3OH), ammonia (NH3), hydrogen and more.The gasifier performances were analysed using different CO2/O2 ratios in the feed (between 1 and 3 kg/kg). The inlet biomass flow rate was approximately 12–18 kg/h, while the equivalence ratio ranged between 19 % and 26 %. The results show that the gasifier can produce a syngas flow rate in the range of 15–25 Nm3/h with a lower heating value (LHV) of between 8 and 10 MJ/Nm3 and a cold gas efficiency of up to 78 %. The operative behaviour of the gasification system is stable and simple to control.

Soil Ecosystem Functioning through Interactions of Nematodes and Fungi Trichoderma sp.

In this review, an overview was given of the mutual interactions between nematodes and fungi of the genus Trichoderma sp. due to the potential of these fungi to protect plant roots from plant-parasitic nematodes on the one hand and the influence of nematodes (fungivores) on the efficacy of the fungus on the other. In addition, an overview of the advantages of Trichoderma sp. for agricultural production was given. The basis of sustainable agricultural production is the healthy functioning of the soil ecosystem. The diversity of organisms—bacteria, protozoa, algae, metazoans (nematodes) and fungi—improves the quality and performance of the soil by maintaining biological productivity. Root exudates in the rhizosphere support microbial communities that play a key role in regulating the dynamics of organic matter decomposition and the availability of plant nutrients. The microbial activity of organisms in the soil is interconnected and interacts to form a soil food web that reflects the condition, function and health of the soil. The energy in food webs flows through trophic chains of consumers, which are divided into energy channels. Root, bacterial and fungal channels increase soil biomass, carbon (C) and energy flow through the soil food web. The structure of the nematode community is an effective tool for the biological assessment of soil quality. This is due to a number of characteristics that nematodes have, including the following: a great diversity of species, the possibility of subdivision according to different criteria such as trophic groups and c-p groups, the duration of reproduction, the ease of sampling, the identification of genera and preservation, etc. Nematodes are involved in various ecological functions in the soil, of which the interaction between them and fungi is based on antagonism or mutualism, which is the basis for a better understanding of their impact on the ecosystem. Fungi of the genus Trichoderma sp. are successful colonizers of all habitats, secondary opportunists and fast growing.

Development of a neural network model predictive controller for the fluidized bed biomass gasification process

In this study, an advanced controller for the fluidized bed biomass gasification (FBG) process is proposed. The controller is based on the model predictive control method, utilizing a long short-term memory neural network to accurately predict the controlled variable in the FBG process. Then, employing a gradient-based optimization algorithm, it optimizes the inputs to achieve the desired control objective. The controller specifically aims for temperature regulation in three spatial regions (fluidized bed, freeboard and outlet), using primary air, secondary air, and biomass flow rates as input variables. Open-loop simulations are used to fine-tune the controller's parameters (prediction and control horizon). For unbiased controller testing, a computational fluid dynamics (CFD) model of the FBG process is also developed, which is integrated with the controller in a closed-loop system, simulating real-process feedback for performance evaluation. The proposed controller effectively maintains temperatures (steady state error < 1.5 %) at desired set points (800–900 °C) with a short prediction horizon of 24 time steps, reducing response time to under 5 s, making it suitable for real-time FBG process control.

Biotic and thermal drivers alter zooplankton phenology in western Lake Erie

AbstractEnvironmental change, particularly warming and eutrophication, can alter phenology in aquatic systems. Understanding controls on zooplankton phenology is important due to their central role in food webs. While patterns in zooplankton phenology have been well documented, we lack an understanding of how abiotic and biotic drivers influence lake zooplankton phenology during the summer. We examined the phenology of four common zooplankton taxa (Daphnia retrocurva, Skistodiaptomus oregonensis, Mesocyclops spp., Dreissenid veligers) in western Lake Erie during 1995–2022, a period with increasing eutrophication and Bythotrephes longimanus biomass. Many phenology metrics varied by 3 weeks or more from 1995 to 2022. The dominant controls of phenology were temperature and biotic factors, especially grazer‐defended phytoplankton (cyanobacteria and other colonial or filamentous taxa) and the invasive predator B. longimanus, which frequently interacted. Our results show that aspects of environmental change interact to shape zooplankton phenology, which can influence phytoplankton biomass and energy flow to higher trophic levels.

Mathematical Modeling Approach to the Optimization of Biomass Storage Park Management

This paper addresses the critical issue of managing biomass parks, a key component in the shift towards sustainable energy sources. The research problem centers on optimizing the management of these parks to enhance production and economic viability. Our aim was to bridge the gap in current research by developing and applying mathematical models tailored for biomass park management. The study commenced by constructing a basic model based on assumptions such as uniform biomass and steady input rates. Progressing from this initial model, we explored sophisticated control strategies, including Pontryagin’s maximum principle and dynamic programming, and employed numerical methods to tackle the nonlinearities and complexities inherent in biomass management. Our approach’s scope extended to predicting and managing biomass flow, highlighting each method’s distinct advantages. The simple model laid the groundwork for understanding, while optimal control techniques revealed the system’s intricate dynamics. The numerical methods provided practical solutions to complex equations. We found that while each method is beneficial on its own, their combined use can significantly improve decision-making in biomass park management. This research emphasizes the importance of aligning the chosen method with specific operational challenges and desired outcomes for optimal efficacy, offering both theoretical insights and practical applications in the field of renewable energy management.

BRS Paiaguás e BRS Piatã: potencial para uso sob irrigação em ambiente semiárido

ABSTRACT This work aimed to evaluate the physiological parameters, the biomass flow, and the productive characteristics of the grasses BRS Piatã and BRS Paiaguás at different levels of water supply in the semi-arid region. The experiment was carried out in the dry season, in Sobral, Ceará State, Brazil. The following irrigation depths were used: 30, 60, 90, and 120% of ETo. The experiment was carried out in pots with a capacity of 7.5 dm3 at field level, using a 0-0.2m layer of argisol soil as substrate. As a result, the photosynthetic rate was not affected in the largest water treatments. In the biomass flow, the responses of grasses to treatments 90 and 120% of ETo were similar for the variables number of live leaves and phyllochron. Regarding the productive characteristics, pseudo-culm biomass was effective only in the treatment of 120% of ETo, while, for the efficiency of water use, in treatments 60 and 90% of ETo, the difference was effective. In conclusion, in the treatments of 60 and 90% of the ETo, it was possible to maintain good morphological characteristics of the grasses and to increase the biomass production during the dry season in the semi-arid region.

ЭНЕРГЕТИЧЕСКИЙ АНАЛИЗ В СИСТЕМЕ ЗАЩИТНЫХ МЕРОПРИЯТИЙ ПРЕДПРИЯТИЙ АГРАРНОГО СЕКТОРА

This article discusses the issue of the system of protective measures at enterprises of the agricultural sector. Energy plays a key role in farming. The cultivation of crops is based on the conversion of solar energy into biomass. Energy flows are located between two worlds: although energy is a strategic component of the economy, it is also a thermodynamic state variable for describing ecosystems. This situation once again highlights the need to analyze energy flows in agricultural systems. There is a wide variety of approaches used to calculate farm-scale energy flows. This analysis highlights the lack of clear definition of system boundaries in farm-scale research. In addition, most of the research is mainly devoted to socio-economic flows in the sectoral context. However, internal biomass flows, which play a role in maintaining the functionality of the agroecosystem, can also be considered in accordance with a circular/systemic perspective. Thus, some recommendations are given for conducting an exhaustive energy assessment of farming systems, as well as for future research directions. An attempt has been made to conceptualize the implementation of energy expertise in the system of protective measures of the agro-industrial complex enterprise against pests (insects, rodents, birds). The separation of energy in the working part into calculated consumption and losses is proposed, with the transfer of this division to energy consumption and energy intensity of products. Thus, using this method gives a figure of the real value of energy efficiency. This eliminates the uncertainty of the traditional calculation of the energy intensity of products. It also allows for energy expertise of design and technological solutions and to obtain correct information about energy needs. Material products made from raw materials acquire, through the influence of energy, those properties that determine their need in the market. These properties and qualities are given to raw materials in a process called energy technology. There are basically two formulations of the technological process. According to the first, the technological process is a sequence and a set of operations, according to the second, more capacious and arising from the content of the term itself, technology is the science of ways to influence the material, allowing to optimize this effect. The first definition refers more to the organization and structure of production.

Reducing fossil fuel dependency in smallholding farming in l'Horta de València, Spain: A socio-metabolic approach

To favor transition towards sustainable agricultural systems, the agricultural sector needs to reduce its dependence on external inputs. From an ecological economics perspective, this requires the simultaneous fulfillment of a gross energy surplus on the farm (production condition), and a greater recirculation of the production extracted from the agroecosystem (reproduction condition). Using eight smallholder farms, this study focuses on the processes of recirculation and externalization of biomass, materials and energy flows in the agroecosystem. This is carried out through analyzing the MEFA (Material and Energy Flow Analysis) matrix by means of energy return on the investment indexes of inputs or externalizations (EFEROI), recirculations (IFEROI), joint efficiency (NPPact EROI) and labour efficiency (W EROI), all of which impact upon farm-scale decision-making related to yield and cost-benefit situations. Agrarian fossilization indices are applied to include an assessment of farm non-renewable energy profiles. The results indicate a restriction of inputs in conventional farm-operators and a troubling use of indirect fossil-fuel in organic operators, together with a weakening of the agroecosystem reproductive processes by means of external inputs for both systems. To guide the agrarian transition, farming strategies need to focus on reducing indirect fossil-fuel energy consumption, rather than relying on technological substitutions.

Household energy systems based on biomass: Tracing material flows from source to service in rural Ethiopia

Biomass remains the most important energy carrier of rural households in low- and middle-income countries, but its indoor combustion has grave impacts on human health and its extraction is associated with negative effects on ecosystems. Currently, robust and comprehensive data are lacking to trace biomass flows from ecosystems to consumption in households and quantify the related services. This impedes analyses of the social and environmental impacts of biomass use.By developing a source-to-service approach, this paper analyses the provision of domestic energy services in three villages in rural Ethiopia using a socio-metabolic perspective. We combine quantitative and qualitative methods to study the dynamics of domestic biomass use for energy and examine social and environmental implications. We find that the average household consumes 84 GJ/year of biomass (15 GJ per capita/year). Space heating, food and drinking water preparation combined require 86% of domestic energy. Improved cookstoves can reduce domestic energy use by 12%.Our results open new avenues for advancing the scientific understanding of rural energy systems dependent on biomass. These insights are essential to enhance research on sustainable energy systems in rural, bioenergy-dependent areas and may also prove useful in designing policies and innovations to improve provisioning of energy services.

EU Outlook for Biomass Flows and Bio‐based Products

SummaryThe Bioeconomy Strategy Action Plan calls for sustainable extraction, processing, and use of biological resources in Europe as a pathway to achieve environmental, social and economic goals. However, the transition towards sustainable food systems within and across countries is diverse due to the existing heterogeneous land patterns and agricultural production structures, the variety of potential industries competing for specific biomass feedstocks, and the national policy frameworks in place. Therefore, it is key for policymakers to understand how biomass is supplied, and how it flows through the economy and is used for alternative purposes. This calls for tools that can monitor and quantitatively analyse these aspects. BioMAT has projected the annual growth rate of the EU bio‐based chemical production from 2018 to 2030 to be four times higher than its fossil‐based counterpart. The associated net‐availability of industrial sugars in 2030 is quite balanced, but excess demands for starch and plant oils will increase to fulfil requirements of a growing bio‐based chemical sector. As a vast amount of biological feedstock for material use originates from non‐EU regions (e.g. palm oil), sustainable sourcing and a better use of biological residues should be emphasised. Scenario analyses are helpful to consider consequences of assessing different technical pathways or policies.

A methodology based on territorial metabolism analysis to assess the multi-criteria sustainability of African village terroirs with contrasted crop-livestock systems

CONTEXTAgricultural intensification to ensure food security and limit rural exodus is a major issue in sub-Saharan Africa. The potential of livestock farming to improve the sustainability of farming systems has been studied but rarely at the landscape level. However, because the herds move about in the landscape, thereby creating horizontal biomass and nutrient flows between plots and households, the landscape is the only level where all the interactions between the different components of the agro-ecosystem (animals, crops and trees) can be considered. OBJECTIVEOur objective was to develop a methodology that uses territorial metabolism for multicriteria assessment of sustainability to compare contrasted livestock systems. METHODSWe compare two neighboring village terroirs in the former groundnut basin of Senegal. One village (Diohine), has kept a “traditional extensive system” based on fallow, free grazing and night corralling, while the other (Barry) uses a “modern semi-intensive system” based on livestock fattening in which the livestock is stall-fed with feed concentrate and crop residues. During the survey, village households were asked to describe their practices and to quantify biomass and nitrogen (N) flows to enable us to calculate sustainability indicators (productivity, balance, efficiency, dependency, profitability) at plot, household and village terroir levels. RESULTS AND CONCLUSIONSAt village terroir level, introducing livestock fattening increased the livestock stocking rate (0.96 TLU ha-1 in Diohine and 2.31 TLU ha-1 in Barry) and spreading of solid manure on crop fields (respectively 337 and 482 kgDM ha-1). Fattening livestock requires large imports of feed concentrate, 23.67 kgN ha-1 in Barry versus 3.39 kgN ha-1 in Diohine. The improved livestock productivity of fattening (+217 kgLW ha-1) produces higher financial returns (+432€ household-1 year-1) that enable the use of more mineral fertilizers (6.28 kgN ha-1 in Barry versus 1.09 kgN ha-1 in Diohine). The additional N inputs in Barry enable increased yields of the main staple crop (millet) (+101 kgDM ha-1). The population density of Barry village is +78% higher (320 capita km-2 in Barry versus 180 capita km-2 in Diohine). The village nitrogen balance (24.88 kgN ha-1 in Barry versus 8.51 kgN ha-1 in Diohine) and N use efficiencies (respectively 0.64 and 0.15) demonstrate that nutrient cycling and soil fertility management are more sustainable in Barry. SIGNIFICANCEWe propose a methodology to rebuild territorial metabolism from surveys. Territorial metabolism is used to calculate a set of multi-criteria sustainability indicators. This methodology will be particularly useful in sub-Saharan Africa where data on agricultural systems are lacking.