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International audience; Locally, plant species richness supports many ecosystem functions. Yet, the mechanisms driving these often-positive biodiversity–ecosystem functioning relationships are not well understood. Spatial resource partitioning across vertical resource gradients is one of the main hypothesized causes for enhanced ecosystem functioning in more biodiverse grasslands. Spatial resource partitioning occurs if species differ in where they acquire resources and can happen both above- and belowground. However, studies investigating spatial resource partitioning in grasslands provide inconsistent evidence. We present the results of a meta-analysis of 21 datasets from experimental species-richness gradients in grasslands. We test the hypothesis that increasing spatial resource partitioning along vertical resource gradients enhances ecosystem functioning in diverse grassland plant communities above- and belowground. To test this hypothesis, we asked three questions: 1. Does species richness enhance biomass production or community resource uptake across sites? 2. Is there evidence of spatial resource partitioning as indicated by resource tracer uptake and biomass allocation above- and belowground? 3. Is evidence of spatial resource partitioning correlated with increased biomass production or community resource uptake? Although plant species richness enhanced community nitrogen and potassium uptake and biomass production above- and belowground, we found that plant communities did not meet our criteria for spatial resource partitioning, though they did invest in significantly more aboveground biomass in higher canopy layers in mixture relative to monoculture. Furthermore, the extent of spatial resource partitioning across studies was not positively correlated with either biomass production or community resource uptake. Our results suggest that spatial resource partitioning across vertical resource gradients alone does not offer a general explanation for enhanced ecosystem functioning in more diverse temperate grasslands.

On 17 to 19th October 2017, twenty-four academics and practitioners with diverse inter- and transdisciplinary experiences gathered for a workshop to collectively reflect on IPBES’ work and performance. The workshop was held at the German Centre for Integrative Biodiversity Research (iDiv) in Leipzig. The workshop and this report represent an effort to proactively contribute to IPBES’ ongoing (external) review process. The external review process opens up a window of opportunity towards re-thinking the very purpose of IPBES and identifying new pathways to live up to its initial ambitions, such as to move beyond assessments. The workshop identified a spectrum of potential opportunities, provided visions for the future work of IPBES, and collected insights into how to cope with them. While the workshop focussed on identifying future challenges and possible solutions, all participants underlined the great achievements that IPBES has already accomplished. This report provides a synthesis of the workshop discussions. The main recommendations for the external review were: - The external review should seize the opportunity to establish itself in a responsive and future-oriented way so that it not only assesses past performance but also facilitates learning and identifies new pathways for IPBES. It is important that the focus of the review is not just on the extent to which IPBES has fulfilled its ambitions but also on the efficiency with which it has done this, and on the potential unintended effects of decisions. - For IPBES to achieve its initial ambitions, strengthening the (mainly global-scale) scientific knowledge base behind assessments is necessary but not yet sufficient. To meet its broader set of goals, it is required to pay critical attention to all aspects of policy support, knowledge generation and capacity-building, including the meaningful participation of Indigenous Peoples and Local Communities and the incorporation of local and indigenous knowledge. This will require building synergies between knowledge systems, promoting the engagement of the social sciences and humanities, and addressing current challenges in the nomination and selection procedures for the identification of experts. - The external review also opens up space to identify a full range of alternative options and choices that are available when reforming IPBES. The review should engage in real-world dialogues and liaise closely with partners from research, policy and practice as well as with national platforms and local actors., http://www.ufz.de/index.php?en=38006

Targets for human development are increasingly connected with targets for nature, however, existing scenarios do not explicitly address this relationship. Here, we outline a strategy to generate scenarios centred on our relationship with nature to inform decision-making at multiple scales.

We present options for a National Ecosystem Assessment in Germany (NEA-DE) that could inform decision-makers on the state and trends of ecosystems and ecosystem services. Characterizing a NEA-DE, we argue that its cross-sectoral, integrative approach would have the advantages of increased scientific understanding, addressing specific policy questions and creating science-policy dialogues. Challenges include objections against a utilitarian perspective, reservations concerning power relations, and responsibilities concerning the funding.

Bridges is the free, online magazine of the OSTA published by Office of Science & Technology Austria, located in Washington D.C.

Locally, plant species richness supports many ecosystem functions. Yet, the mechanisms driving these often‐positive biodiversity–ecosystem functioning relationships are not well understood. Spatial resource partitioning across vertical resource gradients is one of the main hypothesized causes for enhanced ecosystem functioning in more biodiverse grasslands. Spatial resource partitioning occurs if species differ in where they acquire resources and can happen both above‐ and belowground. However, studies investigating spatial resource partitioning in grasslands provide inconsistent evidence. We present the results of a meta‐analysis of 21 data sets from experimental species‐richness gradients in grasslands. We test the hypothesis that increasing spatial resource partitioning along vertical resource gradients enhances ecosystem functioning in diverse grassland plant communities above‐ and belowground. To test this hypothesis, we asked three questions. (1) Does species richness enhance biomass production or community resource uptake across sites? (2) Is there evidence of spatial resource partitioning as indicated by resource tracer uptake and biomass allocation above‐ and belowground? (3) Is evidence of spatial resource partitioning correlated with increased biomass production or community resource uptake? Although plant species richness enhanced community nitrogen and potassium uptake and biomass production above‐ and belowground, we found that plant communities did not meet our criteria for spatial resource partitioning, though they did invest in significantly more aboveground biomass in higher canopy layers in mixture relative to monoculture. Furthermore, the extent of spatial resource partitioning across studies was not positively correlated with either biomass production or community resource uptake. Our results suggest that spatial resource partitioning across vertical resource gradients alone does not offer a general explanation for enhanced ecosystem functioning in more diverse temperate grasslands., Ecology, 101 (1), ISSN:0012-9658, ISSN:1939-9170