• Energy Research
• 2. Zero hunger close
• DE close
• UA close
• University of Göttingen close

Humans share an extraordinary degree of sociality with other primates, calling for comparative work into the evolutionary drivers of the variation in social engagement observed between species. Of particular interest is the contrast between the chimpanzee (Pan troglodytes) and bonobo (Pan paniscus), the latter exhibiting increased female gregariousness, more tolerant relationships, and elaborate behavioral adaptations for conflict resolution. Here we test predictions from three socio-ecological hypotheses regarding the evolution of these traits using data on wild bonobos at LuiKotale, Democratic Republic of Congo. Focusing on the behavior of co-feeding females and controlling for variation in characteristics of the feeding patch, food intake rate moderately increased while feeding effort decreased with female dominance rank, indicating that females engaged in competitive exclusion from high quality food resources. However, these rank effects did not translate into variation in energy balance, as measured from urinary C-peptide levels. Instead, energy balance varied independent of female rank with the proportion of fruit in the diet. Together with the observation that females join forces in conflicts with males, our results support the hypothesis that predicts that females trade off feeding opportunities for safety against male aggression. The key to a full understanding of variation in social structure may be an integrated view of cooperation and competition over access to the key resources food and mates, both within and between the sexes. main_pan_analysis_II_intake_poisson_script_07022017R script for analysing food intake using a GLMMMASTER_analyses_II_R_file_intake_fFile containing the variables for the GLMM on food intake, analysed in RMAIN_pan_analysis_III_movement_script_26092016R script for analysing movement probability in focal trees using GLMMMASTER_analyses_III_R_file_movement_fFile containing the variables to analyse movement probability with a GLMM in Rmain_ucp_model_script_21022018_seasonality_update_with_feedscansR script to analyse variation in urinary C-peptide in a LMMmain_ucp_model_data_r_2018_seasonality_update_with_feed_scansFile containing the variables to analyse variation in urinary C-peptide using an LMM in R

The expansion of irrigated agriculture has increased global crop production but resulted in widespread stress to freshwater resources. Ensuring that increases in irrigated production only occur in places where water is relatively abundant is a key objective of sustainable agriculture, and knowledge of how irrigated land has evolved is important for measuring progress towards water sustainability. Yet a spatially detailed understanding of the evolution of global area equipped for irrigation (AEI) is missing. Here we utilize the latest sub-national irrigation statistics (covering 17298 administrative units) from various official sources to develop a gridded (5 arc-min resolution) global product of AEI for the years 2000, 2005, 2010, and 2015. We find that AEI increased by 11% from 2000 (297 Mha) to 2015 (330 Mha) with locations of both substantial expansion (e.g., northwest India, northeast China) and decline (e.g., Russia). Combining these outputs with information on green (i.e., rainfall) and blue (i.e., surface and ground) water stress, we also examine to what extent irrigation has expanded unsustainably (i.e., in places already experiencing water stress). We find that more than half (52%) of irrigation expansion has taken place in regions that were already water stressed, with India alone accounting for 36% of global unsustainable expansion. These findings provide new insights into the evolving patterns of global irrigation with important implications for global water sustainability and food security. Recommended citation: Mehta, P., Siebert, S., Kummu, M. et al. Half of twenty-first century global irrigation expansion has been in water-stressed regions. Nat Water (2024). https://doi.org/10.1038/s44221-024-00206-9 Open-access peer reviewed publication available at https://www.nature.com/articles/s44221-024-00206-9 Files G_AEI_*.ASC were produced using the GMIA dataset[https://data.apps.fao.org/catalog/iso/f79213a0-88fd-11da-a88f-000d939bc5d8]. Files MEIER_G_AEI_*.ASC were produced using Meier et al. (2018) dataset [https://doi.pangaea.de/10.1594/PANGAEA.884744].

Background: Temperate agroforestry is regarded as a sustainable alternative to monoculture agriculture due to enhanced provisioning of ecosystem services. Plant health and food safety are crucial requirements for sustainable agriculture; however, studies of fungal diseases and mycotoxin contamination of crops grown under temperate agroforestry are lacking. This study therefore aimed to compare fungal colonization and mycotoxin contamination of crops grown in temperate agroforestry against conventional monoculture. Methods: The biomass of plant pathogenic fungi in oilseed rape plants and barley and wheat grain harvested in 2016 to 2018 at four paired agroforestry and monoculture sites was quantified using species-specific real-time PCR. Mycotoxin content of barley and wheat grain was determined by HPLC-MS/MS. Results: The colonization of oilseed rape plants with the vascular pathogen Verticillium longisporum and wheat grain with the head blight pathogen Fusarium tricinctum was lower in agroforestry than in conventional monoculture. Mycotoxin content of barley and wheat grain did not differ between agroforestry and monoculture systems and did not exceed the legal limits of the EU. Remarkably, fumonisin B1 was detected in wheat grains at two sites in two years, yet the low levels found do not raise food safety concerns. No differences were found between the two production systems with regard to infection of wheat and barley grain with five Fusarium species (F. avenaceum, F. culmorum, F. graminearum, F. poae, and F. proliferatum) and oilseed rape with fungal pathogens Leptosphaeria biglobosa, Leptosphaeria maculans, and Sclerotinia sclerotiorum. Conclusions: Temperate agroforestry does not negatively affect the infection of wheat, barley and oilseed rape with major fungal pathogens though it may suppress the infection of oilseed rape with V. longisporum and wheat grain with F. tricinctum. Furthermore, temperate agroforestry does not increase mycotoxin contamination of barley and wheat. Therefore, temperate agroforestry does not negatively affect food safety.

Increased seasonal climatic variability is a major contributor to uncertainty in livestock-based livelihoods across Southern Africa. Erratic rainfall patterns and prolonged droughts have resulted in the region being identified as a climate ‘vulnerability hotspot’. Based on fieldwork conducted in the dry seasons in a semiarid region of South Africa, we present an interdisciplinary approach to assess the differential effects of drought on two types of livestock systems. Organic matter digestibility, faecal crude protein, C/N ratio and the natural abundance of faecal 15N and 13C isotopes were used as ecophysiological feed quality indicators between smallholder and semicommercial systems. These measurements were complemented with qualitative surveys. In a novel approach, we tested the potential of the isotopic signature to predict feed quality and present a significant relationship between organic matter digestibility and isotopic ratios. Indicators assessed smallholder feed quality to be significantly higher than semicommercial feed. However, animals from semicommercial farms were in significantly better condition than those from smallholding farms. Differential access to feed resources suggests that a complex feed–water–land nexus pushes smallholders into high reliance on off-farm supplements to bridge drought-induced feed deficits. The paper thus offers a contribution to intersectional work on drought effects on livestock keepers of semiarid South Africa and illustrates how ecophysiological indicators mirror socioeconomic differences.

Abstract Background Energy crop production for biogas still relies mainly on maize, but the co-digestion of alternative energy crops (legumes, amaranth, ryegrass, flower mixtures) with maize can have several advantages. First, a greater biodiversity in the fields; second, an enrichment of essential trace elements in biogas substrates (cobalt, nickel, manganese, and molybdenum); and third, less use of artificial trace element additives. Methods In two randomized field trials, 12 different variants of field crops in sole, double and intercropping were tested over a 2-year period. Dry matter yield, trace element content of the crops, and soil parameters like soil texture, pH, and soil element concentration were determined. The trace element concentrations in biogas plants resulting from input mixtures of energy crops (legumes, amaranth, faba bean, and ryegrass) and maize are calculated. Results High dry matter yields were obtained for ryegrass, maize, winter faba bean maize, intercropping winter faba bean/triticale-maize, and intercropping rye/vetch-maize. The double croppings with maize reached highest total yields (ca. 30 t DM ha−1). Total element deliveries from the harvest reveal large differences between the variants and the trace elements. Cobalt is provided most by summer faba bean maize and intercropping of winter faba bean/triticale-maize. Ryegrass can deliver the greatest amounts of Manganese and Molybdenum to biogas plants. When these energy crops are added to conventional maize input for biogas production, the trace element concentration in the fermenter can be raised significantly, e.g., 0.03 g Co t−1 FM can be attained compared to 0.003 g t−1 with maize silage input only. Sufficient Co can be provided by addition of manure to the input mixture. Conclusions Alternative energy crops in combination with maize ensure a good dry matter yield per year and provide significantly more trace elements. However, these substrate mixtures alone do not provide enough trace elements, particularly Co. However, enough Co can be supplied by a small addition of manure.

Abstract A central challenge of today's ecological research is predicting how ecosystems will develop under future global change. Accurate predictions are complicated by (a) simultaneous effects of different drivers, such as climate change, nitrogen deposition and management changes; and (b) legacy effects from previous land use. We tested whether herb layer biodiversity (i.e. richness, Shannon diversity and evenness) and functional (i.e. herb cover, specific leaf area [SLA] and plant height) responses to environmental change drivers depended on land‐use history. We used resurvey data from 192 plots across nineteen European temperate forest regions, with large spatial variability in environmental change factors. We tested for interactions between land‐use history, distinguishing ancient and recent (i.e. post‐agricultural) forests and four drivers: temperature, nitrogen deposition, and aridity at the regional scale and light dynamics at the plot‐scale. Land‐use history significantly modulated global change effects on the functional signature of the herb layer (i.e. cover, SLA and plant height). Light availability was the main environmental driver of change interacting with land‐use history. We found greater herb cover and plant height decreases and SLA increases with decreasing light availability in ancient than in recent forests. Furthermore, we found greater decreases in herb cover with increased nitrogen deposition in ancient forests, whereas warming had the strongest decreasing effect on the herb cover in recent forests. Interactive effects between land‐use history and global change on biodiversity were not found, but species evenness increased more in ancient than in recent forests. Synthesis. Our results demonstrate that land‐use history should not be overlooked when predicting forest herb layer responses to global change. Moreover, we found that herb layer composition in semi‐natural deciduous forests is mainly controlled by local canopy characteristics, regulating light levels at the forest floor, and much less by environmental changes at the regional scale (here: warming, nitrogen deposition and aridity). The observed disconnect between biodiversity and functional herb layer responses to environmental changes demonstrates the importance of assessing both types of responses to increase our understanding of the possible impact of global change on the herb layer.

Over the past 70 years, the world has witnessed extraordinary growth in crop productivity, enabled by a suite of technological advances, including higher yielding crop varieties, improved farm management, synthetic agrochemicals, and agricultural mechanization. While this “Green Revolution” intensified crop production, and is credited with reducing famine and malnutrition, its benefits were accompanied by several undesirable collateral effects (Pingali, 2012). These include a narrowing of agricultural biodiversity, stemming from increased monoculture and greater reliance on a smaller number of crops and crop varieties for the majority of our calories. This reduction in diversity has created vulnerabilities to pest and disease epidemics, climate variation, and ultimately to human health (Harlan, 1972). The value of crop diversity has long been recognized (Vavilov, 1992). A global system of genebanks (e.g., www.genebanks.org/genebanks/) was established in the 1970s to conserve the abundant genetic variation found in traditional “landrace” varieties of crops and in crop wild relatives (Harlan, 1972). While preserving crop variation is a critical first step, the time has come to make use of this variation to breed more resilient crops. The DivSeek International Network (https://divseekintl.org/) is a scientific, not-for-profit organization that aims to accelerate such efforts.