• Energy Research
• 2. Zero hunger close
• US close
• CN close
• Technical University of Munich close

AbstractConversion of semi-natural habitats, such as field margins, fallows, hedgerows, grassland, woodlots and forests, to agricultural land could increase agricultural production and help meet rising global food demand. Yet, the extent to which such habitat loss would impact biodiversity and wild species is unknown. Here we survey species richness for four taxa (vascular plants, earthworms, spiders, wild bees) and agricultural yield across a range of arable, grassland, mixed, horticulture, permanent crop, for organic and non-organic agricultural land on 169 farms across 10 European regions. We find that semi-natural habitats currently constitute 23% of land area with 49% of species unique to these habitats. We estimate that conversion of semi-natural land that achieves a 10% increase in agricultural production will have the greatest impact on biodiversity in arable systems and the least impact in grassland systems, with organic practices having better species retention than non-organic practices. Our findings will help inform sustainable agricultural development.

Abstract Increasing global food demand will require more food production without further exceeding the planetary boundaries, while at the same time adapting to climate change. We used an ensemble of wheat simulation models, with sink-source improved traits from the highest-yielding wheat genotypes to quantify potential yield gains and associated N requirements. This was explored for current and climate change scenarios across representative sites of major world wheat producing regions. The sink-source traits emerged as climate neutral with 16% yield increase with current N fertilizer applications under both current climate and mid-century climate change scenarios. To achieve the full yield potential, a 52% increase in global average yield under a mid-century RCP8.5 climate scenario, fertilizer use would need to increase fourfold over current use, which would unavoidably lead to higher environmental impacts from wheat production. Our results show the need to improve soil N availability and N use efficiency, along with yield potential.

AbstractThe data set contains information on aboveground vegetation traits of > 100 georeferenced locations within ten temperate pre-Alpine grassland plots in southern Germany. The grasslands were sampled in April 2018 for the following traits: bulk canopy height; weight of fresh and dry biomass; dry weight percentage of the plant functional types (PFT) non-green vegetation, legumes, non-leguminous forbs, and graminoids; total green area index (GAI) and PFT-specific GAI; plant water content; plant carbon and nitrogen content (community values and PFT-specific values); as well as leaf mass per area (LMA) of PFT. In addition, a species specific inventory of the plots was conducted in June 2020 and provides plot-level information on grassland type and plant species composition. The data set was obtained within the framework of the SUSALPS project (“Sustainable use of alpine and pre-alpine grassland soils in a changing climate”;https://www.susalps.de/) to providein-situdata for the calibration and validation of remote sensing based models to estimate grassland traits.

Urban aquifers are experiencing increasing pressures from climate change, land-use change, and abstraction, consequently, altering groundwater levels and threatening sustainable water availability, consumption, and utilization. Sustainability in such areas requires the adaptation of groundwater resources to these stressors. Consequently, this research made projections about future climate, land use, and abstraction, examines how these drives will affect groundwater levels, and then proposes adaptation strategies to reduce the impact on Lahore’s groundwater resources. The objectives are achieved using an integrated modeling framework involving applications of Soil Water Assessment Tool (SWAT) and MODFLOW models. The results indicated a projected rise in Tmin by ~2.03 °C and Tmax by ~1.13 °C by 2100 under medium (RCP 4.5) and high-end (RCP 8.5) scenarios, respectively. Future precipitation changes for mid, near and far periods are projected to be −1.0%, 25%, and 24.5% under RCP4.5, and −17.5%, 27.5%, and 29.0% under RCP8.5, respectively. The built-up area in the Lahore division will dominate agricultural land in the future with an expansion from 965 m2 to 3716 km2 by the year 2100 under R1S1 (R2S2) land-use change scenarios (significant at p = 5%). The future population of the Lahore division will increase from 6.4 M to 24.6 M (28.7 M) by the year 2100 under SSP1 (SSP3) scenarios (significant at p = 5%). Groundwater level in bult-up areas will be projected to decline from 185 m to 125 m by 2100 due to increasing groundwater abstraction and expansion in the impermeable surface under all scenarios. In contrast, agricultural areas show a fluctuating trend with a slight increase in groundwater level due to decreasing abstraction and multiple recharge sources under combined scenarios. The results of this study can be a way forward for groundwater experts and related institutions to understand the potential situation of groundwater resources in the Lahore division and implement adaptation strategies to counteract diminishing groundwater resources.

It remains unclear whether biodiversity buffers ecosystems against climate extremes, which are becoming increasingly frequent worldwide. Early results suggested that the ecosystem productivity of diverse grassland plant communities was more resistant, changing less during drought, and more resilient, recovering more quickly after drought, than that of depauperate communities. However, subsequent experimental tests produced mixed results. Here we use data from 46 experiments that manipulated grassland plant diversity to test whether biodiversity provides resistance during and resilience after climate events. We show that biodiversity increased ecosystem resistance for a broad range of climate events, including wet or dry, moderate or extreme, and brief or prolonged events. Across all studies and climate events, the productivity of low-diversity communities with one or two species changed by approximately 50% during climate events, whereas that of high-diversity communities with 16-32 species was more resistant, changing by only approximately 25%. By a year after each climate event, ecosystem productivity had often fully recovered, or overshot, normal levels of productivity in both high- and low-diversity communities, leading to no detectable dependence of ecosystem resilience on biodiversity. Our results suggest that biodiversity mainly stabilizes ecosystem productivity, and productivity-dependent ecosystem services, by increasing resistance to climate events. Anthropogenic environmental changes that drive biodiversity loss thus seem likely to decrease ecosystem stability, and restoration of biodiversity to increase it, mainly by changing the resistance of ecosystem productivity to climate events.

Abstract As bioenergy plants, short rotation woody crops (SRWC) feature high biomass productivity and provide positive external effects, such as reduced soil erosion, increased soil life, and reduced nitrate leaching. However, they are not widespread in intensive cropping systems due to long investment periods and perceived economic disadvantages (low profitability and high risk). Nevertheless, the perceived uncertainty as the main barrier of adoption has not been addressed sufficiently, since the economic risk of SRWC has not been quantified and compared with conventional crops extensively. Another shortcoming of recent economic evaluations is that they are based on mutually exclusive comparisons of alternative investments. In fact, SRWC can be considered an asset of agricultural portfolios, whereby diversification effects are expected due to different ecology, products, and markets. To address these shortcomings, we quantified the economic risk of SRWC and conventional crops and applied the Modern Portfolio Theory to evaluate the economic diversification effects of SRWC at the farm level in a low- and a high-yielding study region in Bavaria (Germany). In SRWC-crop comparisons, SRWC showed the lowest economic risk of all crops compared and gross margins which were competitive with most alternative crops. Furthermore, the correlation of the gross margins of SRWC and agricultural crops compared was relatively low. Therefore, the inclusion of SRWC into existing farm production plans offered economic diversification, increasing the profitability at farm scale, while lowering risk. Thus, diversifying cash crop rotations with SRWC is an effective risk-management instrument that can furthermore provide positive external effects.

•Premise of the study:The study of how phenology may contribute to the assembly of plant communities has a long history in ecology. Climate change has brought renewed interest in this area, with many studies examining how phenology may contribute to the success of exotic species. In particular, there is increasing evidence that exotic species occupy unique phenological niches and track climate change more closely than native species.•Methods:Here, we use long‐term records of species’ first flowering dates from five northern hemisphere temperate sites (Chinnor, UK and in the United States, Concord, Massachusetts; Fargo, North Dakota; Konza Prairie, Kansas; and Washington, D.C.) to examine whether invaders have distinct phenologies. Using a broad phylogenetic framework, we tested for differences between exotic and native species in mean annual flowering time, phenological changes in response to temperature and precipitation, and longer‐term shifts in first flowering dates during recent pronounced climate change (“flowering time shifts”).•Key results:Across North American sites, exotic species have shifted flowering with climate change while native species, on average, have not. In the three mesic systems, exotic species exhibited higher tracking of interannual variation in temperature, such that flowering advances more with warming, than native species. Across the two grassland systems, however, exotic species differed from native species primarily in responses to precipitation and soil moisture, not temperature.•Conclusions:Our findings provide cross‐site support for the role of phenology and climate change in explaining species’ invasions. Further, they support recent evidence that exotic species may be important drivers of extended growing seasons observed with climate change in North America.