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6 páginas.-- 50 referencia.-- This article is Free access in the https://doi.org/10.1111/1365-2745.13040 ; The quest for understanding the maintenance of species diversity has matured in recent decades under the umbrella of species coexistence theory, founded by Chesson (2000). The central conclusion of the theory is that coexistence at local scales depends on two opposing forces: average fitness differences between species, which drive the best-adapted species to exclude others, and stabilizing mechanisms, which promote diversity via niche differentiation. Recent theoretical work has focussed on how interactions between plants and other organisms influence the equalizing and stabilizing forces. However, there is a lack of empirical information. Therefore, the next fundamental step is to assess the prevalence of these mechanisms for controlling plant coexistence across a wide range of interactions and systems. To that end, this special feature presents 10 theoretical, observational, or manipulative studies illustrating 9 different biotic interactions including mutualisms (pollinators, seed dispersers, soil microbes, and arbuscular mycorrhizal fungi) and antagonisms (leaf and seed herbivores, and leaf and root pathogens). All studies share a common question: how biotic interactions regulate plant coexistence? Comparisons across studies suggest that biotic interactions modify both stabilizing and average fitness differences. In those cases where biotic interactions promote stable coexistence between plant species, both mutualistic and antagonistic interactions act more frequently as an equalizing rather than as a stabilizing mechanisms. Besides these generalities, the studies of this special issue also present novel theoretical and empirical approaches to better understand the maintenance of species diversity over a wide variety of systems, environmental conditions, and organisms. Synthesis. The studies presented here constitutes a solid base to empirically explore how mutualistic and antagonistic interactions act upon the determinants of plant species competition, and open novel paths for future research. Collectively, these advances will serve to pave the road for a better theoretical and empirical understanding of how biotic interactions control biodiversity ; We thank James Ross and Mark Rees for a swift editorial assistance. Ideas were develop edunderhe Lincx project (CGL2014‐61590‐EXP). O.G. acknowledges postdoctoral financial support provided by the European Union Horizon research and innovation program under the Marie Sklodowska‐Curie grant agreement no 661118‐BioFUNC. ; Peer reviewed

10 páginas.-- 4 figuras.-- 1 tablas.-- 50 referencias.-- Additional Supporting Information may be found online inthe supporting information tab for this article https://doi.org/10.1111/ele.12954 ; Theory argues that both soil conditions and aboveground trophic interactions have equivalent potential to limit or promote plant diversity. However, it remains unexplored how they jointly modify the niche differences stabilising species coexistence and the average fitness differences driving competitive dominance. We conducted a field study in Mediterranean annual grasslands to parameterise population models of six competing plant species. Spatially explicit floral visitor assemblages and soil salinity variation were characterised for each species. Both floral visitors and soil salinity modified species population dynamics via direct changes in seed production and indirect changes in competitive responses. Although the magnitude and sign of these changes were species‐specific, floral visitors promoted coexistence at neighbourhood scales, while soil salinity did so over larger scales by changing the superior competitors' identity. Our results show how below and aboveground interactions maintain diversity in heterogeneous landscapes through their opposing effects on the determinants of competitive outcomes. ; Fnancial support provided by the European Union Horizon2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No 661118-BioFUNC. IB and OG acknowledge also financial support provided by the Spanish Ministry of Economy and Competitiveness, Explora Program (CGL2014-61590-EXP, LINCX). ; Peer reviewed

14 páginas.-- 4 figuras.-- 1 tabla.-- 100 referencias.-- Supplemental information associated with this article can be found, in the online version, at https://doi.org/10.1016/j.tree.2018.01.007 ; We propose to integrate niche and network theories into a single framework. This integration is possible through the strong parallelisms of concepts and methodologies of both theories. Feasibility and stability conditions are the key concepts that can allow the integration. How species interactions across trophic levels fulfill feasibility and stability conditions is yet to be discovered. The quest for understanding how species interactions modulate diversity has progressed by theoretical and empirical advances following niche and network theories. Yet, niche studies have been limited to describe coexistence within tropic levels despite incorporating information about multi-trophic interactions. Network approaches could address this limitation, but they have ignored the structure of species interactions within trophic levels. Here we call for the integration of niche and network theories to reach new frontiers of knowledge exploring how interactions within and across trophic levels promote species coexistence. This integration is possible due to the strong parallelisms in the historical development, ecological concepts, and associated mathematical tools of both theories. We provide a guideline to integrate this framework with observational and experimental studies. ; Comments from three anonymous reviewers greatly improve the quality of this paper, which is the result of a collaborative project funded by the Spanish Ministry of Economy and Competitiveness (LINCX, CGL2014-61590-EXP). OG acknowledges postdoctoral financial support provided by the Spanish Ministry of Economy and Competitiveness (JCI-2012-12061) and by the European Union Horizon 2020 research and innovation program under the Marie Sklodowska- Curie grant agreement No 661118-BioFUNC.SS alsoacknowledges support from MIT Research Committee Funds and the Mitsui Chair. Wefinally thank Phylopic.com and Melissa Broussard for providing silhouette images of plants and pollinators. ; Peer reviewed

Wildbienen sind eine wichtige Bestäubergruppe. In meiner Dissertation untersuche ich die interaktive Wirkung von Landschaftsstruktur und Wetter auf die Diversität und Stabilität der Wildbienengemeinschaften in landwirtschaftlichen Landschaften. Ich beurteile die indirekten Effekte der Landschaft auf die Bienen- und Blütenpflanzenvielfalt, die sich aus ihrer Interdependenz ergeben. Ich verwende Daten aus zwei Monitoringprogrammen, die verschiedene zeitliche und räumliche Skalen umfassen. Vorteilhafte Landschaftsbedingungen mildern die Auswirkung derTemperaturänderungen auf die Stabilität und Vielfalt der Bienen, aber reichen bei stark variierenden Niederschlägen nicht aus. Der demonstrierte enge Zusammenhang zwischen Bienen- und Blütenpflanzenvielfalt führt zu indirekten Effekten der Landschaft auf beide Artengruppen. Meine Ergebnisse betonen die Wichtigkeit der kombinierten Effekte von Stressoren und die Zusammenhänge zwischen interagierenden Artengruppen beim Schutz von Bestäubern.

International agreements aim to conserve 17% of Earth's land area by 2020 but include no area-based conservation targets within the working landscapes that support human needs through farming, ranching, and forestry. Through a review of country-level legislation, we found that just 38% of countries have minimum area requirements for conserving native habitats within working landscapes. We argue for increasing native habitats to at least 20% of working landscape area where it is below this minimum. Such target has benefits for food security, nature's contributions to people, and the connectivity and effectiveness of protected area networks in biomes in which protected areas are underrepresented. We also argue for maintaining native habitat at higher levels where it currently exceeds the 20% minimum, and performed a literature review that shows that even more than 50% native habitat restoration is needed in particular landscapes. The post-2020 Global Biodiversity Framework is an opportune moment to include a minimum habitat restoration target for working landscapes that contributes to, but does not compete with, initiatives for expanding protected areas, the UN Decade on Ecosystem Restoration (2021–2030) and the UN Sustainable Development Goals.

International agreements aim to conserve 17% of Earth's land area by 2020 but include no area‐based conservation targets within the working landscapes that support human needs through farming, ranching, and forestry. Through a review of country‐level legislation, we found that just 38% of countries have minimum area requirements for conserving native habitats within working landscapes. We argue for increasing native habitats to at least 20% of working landscape area where it is below this minimum. Such target has benefits for food security, nature's contributions to people, and the connectivity and effectiveness of protected area networks in biomes in which protected areas are underrepresented. We also argue for maintaining native habitat at higher levels where it currently exceeds the 20% minimum, and performed a literature review that shows that even more than 50% native habitat restoration is needed in particular landscapes. The post‐2020 Global Biodiversity Framework is an opportune moment to include a minimum habitat restoration target for working landscapes that contributes to, but does not compete with, initiatives for expanding protected areas, the UN Decade on Ecosystem Restoration (2021–2030) and the UN Sustainable Development Goals.

Agricultural intensification and associated loss of high-quality habitats are key drivers of insect pollinator declines. With the aim of decreasing the environmental impact of agriculture, the 2014 EU Common Agricultural Policy (CAP) defined a set of habitat and landscape features (Ecological Focus Areas: EFAs) farmers could select from as a requirement to receive basic farm payments. To inform the post-2020 CAP, we performed a European-scale evaluation to determine how different EFA options vary in their potential to support insect pollinators under standard and pollinator-friendly management, as well as the extent of farmer uptake. A structured Delphi elicitation process engaged 22 experts from 18 European countries to evaluate EFAs options. By considering life cycle requirements of key pollinating taxa (i.e. bumble bees, solitary bees and hoverflies), each option was evaluated for its potential to provide forage, bee nesting sites and hoverfly larval resources. EFA options varied substantially in the resources they were perceived to provide and their effectiveness varied geographically and temporally. For example, field margins provide relatively good forage throughout the season in Southern and Eastern Europe but lacked early-season forage in Northern and Western Europe. Under standard management, no single EFA option achieved high scores across resource categories and a scarcity of late season forage was perceived. Experts identified substantial opportunities to improve habitat quality by adopting pollinator-friendly management. Improving management alone was, however, unlikely to ensure that all pollinator resource requirements were met. Our analyses suggest that a combination of poor management, differences in the inherent pollinator habitat quality and uptake bias towards catch crops and nitrogen-fixing crops severely limit the potential of EFAs to support pollinators in European agricultural landscapes. Policy Implications. To conserve pollinators and help protect pollination services, our expert elicitation highlights the need to create a variety of interconnected, well-managed habitats that complement each other in the resources they offer. To achieve this the Common Agricultural Policy post-2020 should take a holistic view to implementation that integrates the different delivery vehicles aimed at protecting biodiversity (e.g. enhanced conditionality, eco-schemes and agri-environment and climate measures). To improve habitat quality we recommend an effective monitoring framework with target-orientated indicators and to facilitate the spatial targeting of options collaboration between land managers should be incentivised.

Background and aims – Agricultural intensification and loss of farmland heterogeneity have contributed to population declines of wild bees and other pollinators, which may have caused subsequent declines in insect-pollinated wild plants. Material and methods – Using data from 37 studies on 22 pollinator-dependent wild plant species across Europe, we investigated whether flower visitation and seed set of insect-pollinated plants decline with an increasing proportion of arable land within 1 km. Key results – Seed set increased with increasing flower visitation by bees, most of which were wild bees, but not with increasing flower visitation by other insects. Increasing proportion of arable land had a strongly variable effect on seed set and flower visitation by bees across studies. Conclusion – Factors such as landscape configuration, local habitat quality, and temporally changing resource availability (e.g. due to mass-flowering crops or honey bee hives) could have modified the effect of arable land on pollination. While our results highlight that the persistence of wild bees is crucial to maintain plant diversity, we also show that pollen limitation due to declining bee populations in homogenized agricultural landscapes is not a universal driver causing parallel losses of bees and insect-pollinated plants. ; EU FP5 QLRT-2001-01495 ; Swiss Federal Office for Science and Technology (01·0524-2) ; FORMAS ; Estonian Ministry of Education and Research IUT (IUT20-33) ; Internal Grant Agency of the Faculty of Environmental Sciences Czech University of Life Sciences Prague 42900/1312/3166 ; MC-CIG BeeFun project: PCIG14-GA-2013-631653 ; DAFM ; IRC ; Formas (2018-01466) ; German Ministry of Research and Education (FKZ: 01LC1104A) ; NKFIH project (FK123813) ; NKFIH (KKP 133839) ; European Union in the 7th Framework Programme (grant 244090), ; MTA Bolyai Fellow ; Peer reviewed

Background and aims: Agricultural intensification and loss of farmland heterogeneity have contributed to population declines of wild bees and other pollinators, which may have caused subsequent declines in insect-pollinated wild plants. Material and methods: Using data from 37 studies on 22 pollinator-dependent wild plant species across Europe, we investigated whether flower visitation and seed set of insect-pollinated plants decline with an increasing proportion of arable land within 1 km. Key results: Seed set increased with increasing flower visitation by bees, most of which were wild bees, but not with increasing flower visitation by other insects. Increasing proportion of arable land had a strongly variable effect on seed set and flower visitation by bees across studies. Conclusion:Factors such as landscape configuration, local habitat quality, and temporally changing resource availability (e.g. due to mass-flowering crops or honey bee hives) could have modified the effect of arable land on pollination. While our results highlight that the persistence of wild bees is crucial to maintain plant diversity, we also show that pollen limitation due to declining bee populations in homogenized agricultural landscapes is not a universal driver causing parallel losses of bees and insect-pollinated plants. ; The original idea was conceived aspart of the project 'STEP - Status and trends of Europeanpollinators' funded by the European Union in the 7thFramework Programme (grant 244090), which fundedRB, ISD, HGS, SP, MR, LH, JME, and KS. JE and PCwere funded by MULTAGRI/FORMAS. MA was fundedby the EU FP5 project 'Evaluating current European agri-environment schemes to quantify and improve natureconservation efforts in agricultural landscapes' (EASY;QLRT-2001-01495) and the Swiss Federal Office for Scienceand Technology (01·0524-2). AJ and EÖ were funded byFORMAS. TTe and VS were supported by institutionalresearch funding IUT (IUT20-33) of the Estonian Ministryof Education and Research, and TTe also received funding(grant no. 42900/1312/3166) from the Internal Grant Agencyof the Faculty of Environmental Sciences, Czech Universityof Life Sciences Prague. IB was funded by MC-CIG BeeFunproject: PCIG14-GA-2013-631653 and thanks the DoñanaNP staff members for granting access to the Park and CurroMolina for conducting the field work. JS, EFP, and SM werefunded by DAFM and IRC. LH was funded by a grant fromFormas to HGS and by a mobility grant from Formas (2018-01466). ALH was funded by the FarmLand project supportedby the German Ministry of Research and Education (FKZ:01LC1104A). AKH was supported by the NKFIH project 348Pl. Ecol. Evol.154 (3), 2021(FK123813) and was a Bolyai Fellow of MTA. PB wassupported by the NKFIH (KKP 133839).

Agricultural intensification and associated loss of high-quality habitats are key drivers of insect pollinator declines. With the aim of decreasing the environmental impact of agriculture, the 2014 EU Common Agricultural Policy (CAP) defined a set of habitat and landscape features (Ecological Focus Areas: EFAs) farmers could select from as a requirement to receive basic farm payments. To inform the post-2020 CAP, we performed a European-scale evaluation to determine how different EFA options vary in their potential to support insect pollinators under standard and pollinator-friendly management, as well as the extent of farmer uptake.A structured Delphi elicitation process engaged 22 experts from 18 European countries to evaluate EFAs options. By considering life cycle requirements of key pollinating taxa (i.e. bumble bees, solitary bees and hoverflies), each option was evaluated for its potential to provide forage, bee nesting sites and hoverfly larval resources.EFA options varied substantially in the resources they were perceived to provide and their effectiveness varied geographically and temporally. For example, field margins provide relatively good forage throughout the season in Southern and Eastern Europe but lacked early-season forage in Northern and Western Europe. Under standard management, no single EFA option achieved high scores across resource categories and a scarcity of late season forage was perceived.Experts identified substantial opportunities to improve habitat quality by adopting pollinator-friendly management. Improving management alone was, however, unlikely to ensure that all pollinator resource requirements were met. Our analyses suggest that a combination of poor management, differences in the inherent pollinator habitat quality and uptake bias towards catch crops and nitrogen-fixing crops severely limit the potential of EFAs to support pollinators in European agricultural landscapes. Policy Implications. To conserve pollinators and help protect pollination services, our expert ...

Agricultural intensification and associated loss of high-quality habitats are key drivers of insect pollinator declines. With the aim of decreasing the environmental impact of agriculture, the 2014 EU Common Agricultural Policy (CAP) defined a set of habitat and landscape features (Ecological Focus Areas: EFAs) farmers could select from as a requirement to receive basic farm payments. To inform the post-2020 CAP, we performed a European-scale evaluation to determine how different EFA options vary in their potential to support insect pollinators under standard and pollinator-friendly management, as well as the extent of farmer uptake. A structured Delphi elicitation process engaged 22 experts from 18 European countries to evaluate EFAs options. By considering life cycle requirements of key pollinating taxa (i.e. bumble bees, solitary bees and hoverflies), each option was evaluated for its potential to provide forage, bee nesting sites and hoverfly larval resources. EFA options varied substantially in the resources they were perceived to provide and their effectiveness varied geographically and temporally. For example, field margins provide relatively good forage throughout the season in Southern and Eastern Europe but lacked early-season forage in Northern and Western Europe. Under standard management, no single EFA option achieved high scores across resource categories and a scarcity of late season forage was perceived. Experts identified substantial opportunities to improve habitat quality by adopting pollinator-friendly management. Improving management alone was, however, unlikely to ensure that all pollinator resource requirements were met. Our analyses suggest that a combination of poor management, differences in the inherent pollinator habitat quality and uptake bias towards catch crops and nitrogen-fixing crops severely limit the potential of EFAs to support pollinators in European agricultural landscapes. Policy Implications. To conserve pollinators and help protect pollination services, our expert ...

1. Agricultural intensification and associated loss of high‐quality habitats are key drivers of insect pollinator declines. With the aim of decreasing the environmental impact of agriculture, the 2014 EU Common Agricultural Policy (CAP) defined a set of habitat and landscape features (Ecological Focus Areas: EFAs) farmers could select from as a requirement to receive basic farm payments. To inform the post‐2020 CAP, we performed a European‐scale evaluation to determine how different EFA options vary in their potential to support insect pollinators under standard and pollinator‐friendly management, as well as the extent of farmer uptake. 2. A structured Delphi elicitation process engaged 22 experts from 18 European countries to evaluate EFAs options. By considering life cycle requirements of key pollinating taxa (i.e. bumble bees, solitary bees and hoverflies), each option was evaluated for its potential to provide forage, bee nesting sites and hoverfly larval resources. 3. EFA options varied substantially in the resources they were perceived to provide and their effectiveness varied geographically and temporally. For example, field margins provide relatively good forage throughout the season in Southern and Eastern Europe but lacked early‐season forage in Northern and Western Europe. Under standard management, no single EFA option achieved high scores across resource categories and a scarcity of late season forage was perceived. 4. Experts identified substantial opportunities to improve habitat quality by adopting pollinator‐friendly management. Improving management alone was, however, unlikely to ensure that all pollinator resource requirements were met. Our analyses suggest that a combination of poor management, differences in the inherent pollinator habitat quality and uptake bias towards catch crops and nitrogen‐fixing crops severely limit the potential of EFAs to support pollinators in European agricultural landscapes. 5. Policy Implications. To conserve pollinators and help protect pollination services, ...

Agricultural intensification and associated loss of high-quality habitats are key drivers of insect pollinator declines. With the aim of decreasing the environmental impact of agriculture, the 2014 EU Common Agricultural Policy (CAP) defined a set of habitat and landscape features (Ecological Focus Areas: EFAs) farmers could select from as a requirement to receive basic farm payments. To inform the post-2020 CAP, we performed a European-scale evaluation to determine how different EFA options vary in their potential to support insect pollinators under standard and pollinator-friendly management, as well as the extent of farmer uptake. A structured Delphi elicitation process engaged 22 experts from 18 European countries to evaluate EFAs options. By considering life cycle requirements of key pollinating taxa (i.e. bumble bees, solitary bees and hoverflies), each option was evaluated for its potential to provide forage, bee nesting sites and hoverfly larval resources. EFA options varied substantially in the resources they were perceived to provide and their effectiveness varied geographically and temporally. For example, field margins provide relatively good forage throughout the season in Southern and Eastern Europe but lacked early-season forage in Northern and Western Europe. Under standard management, no single EFA option achieved high scores across resource categories and a scarcity of late season forage was perceived. Experts identified substantial opportunities to improve habitat quality by adopting pollinator-friendly management. Improving management alone was, however, unlikely to ensure that all pollinator resource requirements were met. Our analyses suggest that a combination of poor management, differences in the inherent pollinator habitat quality and uptake bias towards catch crops and nitrogen-fixing crops severely limit the potential of EFAs to support pollinators in European agricultural landscapes. Policy Implications. To conserve pollinators and help protect pollination services, our expert ...

1. Agricultural intensification and associated loss of high‐quality habitats are key drivers of insect pollinator declines. With the aim of decreasing the environmental impact of agriculture, the 2014 EU Common Agricultural Policy (CAP) defined a set of habitat and landscape features (Ecological Focus Areas: EFAs) farmers could select from as a requirement to receive basic farm payments. To inform the post‐2020 CAP, we performed a European‐scale evaluation to determine how different EFA options vary in their potential to support insect pollinators under standard and pollinator‐friendly management, as well as the extent of farmer uptake. 2. A structured Delphi elicitation process engaged 22 experts from 18 European countries to evaluate EFAs options. By considering life cycle requirements of key pollinating taxa (i.e. bumble bees, solitary bees and hoverflies), each option was evaluated for its potential to provide forage, bee nesting sites and hoverfly larval resources. 3. EFA options varied substantially in the resources they were perceived to provide and their effectiveness varied geographically and temporally. For example, field margins provide relatively good forage throughout the season in Southern and Eastern Europe but lacked early‐season forage in Northern and Western Europe. Under standard management, no single EFA option achieved high scores across resource categories and a scarcity of late season forage was perceived. 4. Experts identified substantial opportunities to improve habitat quality by adopting pollinator‐friendly management. Improving management alone was, however, unlikely to ensure that all pollinator resource requirements were met. Our analyses suggest that a combination of poor management, differences in the inherent pollinator habitat quality and uptake bias towards catch crops and nitrogen‐fixing crops severely limit the potential of EFAs to support pollinators in European agricultural landscapes. 5. Policy Implications. To conserve pollinators and help protect pollination services, ...