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Les changements économiques mondiaux et les interventions politiques conduisent les transitions des systèmes à marée montante (LFS) vers des utilisations alternatives des terres dans les hautes terres d'Asie du Sud-Est. Cette étude présente un examen systématique de l'impact de ces transitions sur les moyens de subsistance et les services écosystémiques dans la région. Plus de 17 000 études publiées entre 1950 et 2015 ont été réduites, en fonction de leur pertinence et de leur qualité, à 93 études pour une analyse plus approfondie. Notre analyse des transitions de l'utilisation des terres des systèmes de culture alternée à intensifiée a montré plusieurs résultats : plus de ménages avaient augmenté le revenu global, mais ces avantages ont entraîné des coûts importants tels que la réduction des pratiques coutumières, le bien-être socio-économique, les options de subsistance et les rendements de base. L'examen des effets des transitions sur les propriétés du sol a révélé des impacts négatifs sur le carbone organique du sol, la capacité d'échange cationique et le carbone hors sol. Pris ensemble, les facteurs immédiats et sous-jacents de la transition de l'EPA vers des utilisations alternatives des terres, en particulier l'intensification des cultures vivaces et annuelles de rente, ont entraîné une baisse significative de la sécurité préexistante des moyens de subsistance et des services écosystémiques soutenant cette sécurité. Nos résultats suggèrent que les politiques imposant des transitions d'utilisation des terres aux agriculteurs des hautes terres afin d'améliorer les moyens de subsistance et les environnements ont été malavisées ; dans le contexte d'utilisations variées des terres, l'agriculture itinérante peut soutenir les moyens de subsistance et les services écosystémiques qui aideront à amortir les impacts du changement climatique en Asie du Sud-Est. El cambio económico global y las intervenciones políticas están impulsando las transiciones de los sistemas de golondrina larga (EPA) a usos alternativos de la tierra en las tierras altas del sudeste asiático. Este estudio presenta una revisión sistemática de cómo estas transiciones impactan en los medios de vida y los servicios ecosistémicos en la región. Más de 17 000 estudios publicados entre 1950 y 2015 se redujeron, en función de la relevancia y la calidad, a 93 estudios para su posterior análisis. Nuestro análisis de las transiciones del uso de la tierra de los sistemas de cultivo sucios a los intensificados mostró varios resultados: más hogares habían aumentado los ingresos generales, pero estos beneficios tuvieron un costo significativo, como la reducción de las prácticas consuetudinarias, el bienestar socioeconómico, las opciones de medios de vida y los rendimientos de los productos básicos. El examen de los efectos de las transiciones en las propiedades del suelo reveló impactos negativos en el carbono orgánico del suelo, la capacidad de intercambio catiónico y el carbono sobre el suelo. En conjunto, los impulsores inmediatos y subyacentes de las transiciones de la EPA a los usos alternativos de la tierra, especialmente la intensificación de los cultivos comerciales perennes y anuales, condujeron a disminuciones significativas en la seguridad de los medios de vida preexistentes y los servicios ecosistémicos que respaldan esta seguridad. Nuestros resultados sugieren que las políticas que imponen transiciones en el uso de la tierra a los agricultores de las tierras altas para mejorar los medios de vida y los entornos han sido erróneas; en el contexto de los diversos usos de la tierra, la agricultura sucia puede apoyar los medios de vida y los servicios ecosistémicos que ayudarán a amortiguar los impactos del cambio climático en el sudeste asiático. Global economic change and policy interventions are driving transitions from long-fallow swidden (LFS) systems to alternative land uses in Southeast Asia's uplands. This study presents a systematic review of how these transitions impact upon livelihoods and ecosystem services in the region. Over 17 000 studies published between 1950 and 2015 were narrowed, based on relevance and quality, to 93 studies for further analysis. Our analysis of land-use transitions from swidden to intensified cropping systems showed several outcomes: more households had increased overall income, but these benefits came at significant cost such as reductions of customary practice, socio-economic wellbeing, livelihood options, and staple yields. Examining the effects of transitions on soil properties revealed negative impacts on soil organic carbon, cation-exchange capacity, and aboveground carbon. Taken together, the proximate and underlying drivers of the transitions from LFS to alternative land uses, especially intensified perennial and annual cash cropping, led to significant declines in pre-existing livelihood security and the ecosystem services supporting this security. Our results suggest that policies imposing land-use transitions on upland farmers so as to improve livelihoods and environments have been misguided; in the context of varied land uses, swidden agriculture can support livelihoods and ecosystem services that will help buffer the impacts of climate change in Southeast Asia. يقود التغيير الاقتصادي العالمي والتدخلات السياسية التحولات من أنظمة الأرياف الطويلة (LFS) إلى استخدامات بديلة للأراضي في مرتفعات جنوب شرق آسيا. تقدم هذه الدراسة مراجعة منهجية لكيفية تأثير هذه التحولات على سبل العيش وخدمات النظم الإيكولوجية في المنطقة. تم تضييق نطاق أكثر من 17000 دراسة نُشرت بين عامي 1950 و 2015، بناءً على الملاءمة والجودة، إلى 93 دراسة لمزيد من التحليل. أظهر تحليلنا للتحولات في استخدام الأراضي من أنظمة زراعة المحاصيل إلى أنظمة زراعة المحاصيل المكثفة العديد من النتائج: فقد زادت المزيد من الأسر من الدخل الإجمالي، لكن هذه الفوائد جاءت بتكلفة كبيرة مثل الحد من الممارسة العرفية، والرفاهية الاجتماعية والاقتصادية، وخيارات سبل العيش، والمحاصيل الأساسية. كشفت دراسة آثار التحولات على خصائص التربة عن آثار سلبية على الكربون العضوي في التربة، وقدرة تبادل الكاتيون، والكربون فوق الأرض. مجتمعة، أدت الدوافع القريبة والأساسية للانتقال من LFS إلى الاستخدامات البديلة للأراضي، وخاصة المحاصيل النقدية الدائمة والسنوية المكثفة، إلى انخفاض كبير في أمن سبل العيش الموجود مسبقًا وخدمات النظام الإيكولوجي التي تدعم هذا الأمن. تشير نتائجنا إلى أن السياسات التي تفرض تحولات في استخدام الأراضي على مزارعي المرتفعات من أجل تحسين سبل العيش والبيئات قد تم تضليلها ؛ في سياق الاستخدامات المتنوعة للأراضي، يمكن للزراعة العشوائية أن تدعم سبل العيش وخدمات النظم الإيكولوجية التي ستساعد في الحد من آثار تغير المناخ في جنوب شرق آسيا.

CONTEXT: Agroforestry is gaining interest in in Europe however the trade-offs associated with its uptake are still uncertain. OBJECTIVE: The objective of this study was to explore the sustainability trade-offs and synergies associated with a range of agroforestry systems in Europe and assess the underlying reasons for different performance regarding environmental, economic, social and governance domains. METHODS: Five case-studies of agroforestry from nothern, eastern and southern Europe were assessed using an established sustainability assessment tool, the Public Goods tool (PG tool). The case studies were selected to represent a range of innovative and traditional systems, encompassing arable and livestock, wood fuel and tree fruit crops. RESULTS AND CONCLUSIONS: All five of the case studies were performing well across a diverse range of sustainability criteria, with average scores of three out of five or higher across the assessment categories. Social capital and animal health and welfare management scores were particularly high, due to high rates of on-farm employment of between 0.4 and 2.3 full-time labour units per hectare, and a high volume of local sales alongside effective health planning and husbandry through health planning and a lack of restrictions on natural behaviour. Land Equivalent Ratios were greater than 1 within each case and were particularly high for established silvopasture systems (over 1.5). Fossil fuel use was considerably lower than the industry average in most of the case studies (between 17 and 92% of the country-average per hectare for three of the cases). Economic performance was highly variable, with high labour costs contributing to negative margins. SIGNIFICANCE: The assessments show that agroforestry systems have considerable potential to contribute to multiple sustainability objectives, and that environmental and social sustainability objectives are particularly well addressed through increased efficiency of land-use, increased opportunities for on-farm employment and engagement with local communities. However considerable financial barriers still exist and may prevent its further uptake. Promoting the future uptake of agroforestry in Europe therefore requires the commitment of multiple actors in supply chains to plan policies, farm-practices and knowledge exchange that can support the delivery of sustainability benefits.

Accelerating climate and land‐use change are rapidly transforming Earth's biodiversity. While there is substantial evidence on the exposure and vulnerability of biodiversity to global change at the species level, the global exposure of intraspecific genetic diversity (GD) is still unknown. Here, we assess the exposure of mitochondrial GD to mid‐21st century climate and land‐use change in terrestrial mammal assemblages at grid‐cell and bioclimatic region scales under alternative narratives of future societal development. We used global predictions of mammal GD distribution based on thousands of georeferenced mitochondrial genes for hundreds of mammal species, the latest generation of global climate models from the ongoing sixth phase of the Coupled Model Intercomparison Project (CMIP6), and global future projections of land‐use prepared for CMIP6. We found that more than 50% of the genetically poorest geographic areas (grid‐cells), primarily distributed in tundra, boreal forests/taiga and temperate bioclimatic regions, will be exposed to mean annual temperature rise that exceeds 2°C compared to the baseline period under all considered future scenarios. We also show that at least 30% of the most genetically rich areas in tropical, subtropical and montane regions will be exposed to an increase of mean annual temperature > 2°C under less optimal scenarios. Genetic diversity in these rich regions is also predicted to be exposed to severe reductions of primary vegetation area and increasing human activities (an average loss of 5–10% of their total area under the less sustainable land‐use scenarios). Our findings reveal a substantial exposure of mammal GD to the combined effects of global climate and land‐use change. Meanwhile the post‐2020 conservation goals are overlooking genetic diversity, our study identifies both genetically poor and highly diverse areas severely exposed to global change, paving the road to better estimate the geography of biodiversity vulnerability to global change.

Abstract The land potential for producing biomass for bioenergy purposes has been highly debated in recent years. The present paper analyses the possibilities and consequences for land use and agricultural production of biofuel production in Denmark based on domestic wheat and rape under specific scenario conditions for the period 2010–2030. The potential is assessed for a situation where policy targets for renewable energy carriers in the transport sector is reached using biofuels, and where second generation ethanol increasingly substitutes first generation ethanol. Three scenarios are developed and evaluated: a baseline, an alternative scenario allowing continuous growth in the now dominant livestock branch and a biofuel scenario assuming that efforts to achieve self-sufficiency in biofuel displaces part of the domestic production of fodder. Results show that the biofuel demand could be met in 2020; but only if current rape oil production is used to satisfy local bio-diesel demand. It would also imply that the Danish bio-diesel export currently supplying a minor part of the German fuel market would seize. In 2030, however, only about 60 percent of the biofuel demand would be covered by self-sufficiency. If biofuels were to displace animal production to make up for this, a reduction of the pig production between 10 and 20 percent would result. Efficiency increases across production branches would allow the animal production to continue un-affected if about half of the rape oil produced for other purposes is utilized.

Abstract Background The rumen microbiota provides essential services to its host and, through its role in ruminant production, contributes to human nutrition and food security. A thorough knowledge of the genetic potential of rumen microbes will provide opportunities for improving the sustainability of ruminant production systems. The availability of gene reference catalogs from gut microbiomes has advanced the understanding of the role of the microbiota in health and disease in humans and other mammals. In this work, we established a catalog of reference prokaryote genes from the bovine rumen. Results Using deep metagenome sequencing we identified 13,825,880 non-redundant prokaryote genes from the bovine rumen. Compared to human, pig, and mouse gut metagenome catalogs, the rumen is larger and richer in functions and microbial species associated with the degradation of plant cell wall material and production of methane. Genes encoding enzymes catalyzing the breakdown of plant polysaccharides showed a particularly high richness that is otherwise impossible to infer from available genomes or shallow metagenomics sequencing. The catalog expands the dataset of carbohydrate-degrading enzymes described in the rumen. Using an independent dataset from a group of 77 cattle fed 4 common dietary regimes, we found that only <0.1% of genes were shared by all animals, which contrast with a large overlap for functions, i.e., 63% for KEGG functions. Different diets induced differences in the relative abundance rather than the presence or absence of genes, which explains the great adaptability of cattle to rapidly adjust to dietary changes. Conclusions These data bring new insights into functions, carbohydrate-degrading enzymes, and microbes of the rumen to complement the available information on microbial genomes. The catalog is a significant biological resource enabling deeper understanding of phenotypes and biological processes and will be expanded as new data are made available.

Abstract Biomass from agricultural residues, especially lignocellulosic biomass, is not only seen as a sustainable biomass source for the production of electricity, but increasingly as a resource for the production of biogas and second generation biofuel in developing countries. Based on empirical research in an irrigated rice-growing area, Office du Niger, in Mali, this article builds scenarios for the sustainable potential of rice straw. The paper concludes that there is great uncertainty regarding the size of the sustainable resources of rice straw available for energy, but that the most likely scenario estimates a resource of about 120,000 t, which would permit up to three 5 MWel rice straw-fuelled power plants. Based on the findings from the empirical studies, the article further suggests that recently published research on the potential of rice straw in a number of African countries seems first to underestimate the uncertainty of resource assessments, and secondly to overestimate the resources available for energy production, mainly due to optimistic residue-to-product ratios and availability factors.

AbstractWarming can alter the biogeochemistry and ecology of soils. These alterations can be particularly large in high northern latitude ecosystems, which are experiencing the most intense warming globally. In this meta‐analysis, we investigated global trends in how experimental warming is altering the biogeochemistry of the most common limiting nutrient for biological processes in cold ecosystems of high northern latitudes (>50°): nitrogen (N). For comparison, we also analyzed cold ecosystems at intermediate and high southern latitudes. In addition, we examined N‐relevant genes and enzymes, and the abundance of belowground organisms. Together, our findings suggest that warming in cold ecosystems increases N mineralization rates and N2O emissions and does not affect N fixation, at least not in a consistent way across biomes and conditions. Changes in belowground N fluxes caused by warming lead to an accumulation of N in the forms of dissolved organic and root N. These changes seem to be more closely linked to increases in enzyme activity that target relatively labile N sources, than to changes in the abundance of N‐relevant genes (e.g., amoA and nosZ). Finally, our analysis suggests that warming in cold ecosystems leads to an increase in plant roots, fungi, and (likely in an indirect way) fungivores, and does not affect the abundance of archaea, bacteria, or bacterivores. In summary, our findings highlight global trends in the ways warming is altering the biogeochemistry and ecology of soils in cold ecosystems, and provide information that can be valuable for prediction of changes and for management of such ecosystems.