Felix Herzog

Global change reshapes arthropod communities, yet long‐term effects on their functional diversity remain unclear. Using a long‐term dataset comprising > 1.3 million individuals of 728 carabid and spider species, we quantified temporal trends in functional diversity across forests, grasslands and croplands. Trajectories diverged strongly among land uses: functional richness increased in forests and grasslands but declined sharply in croplands. In forests, communities became more specialised and less redundant, suggesting increasing niche differentiation, but experienced greater functional richness loss under simulated species extinctions. Cropland assemblages became functionally homogenised. Losses of key effect traits among spiders suggest potential erosion of ecosystem functions in croplands. Moreover, genera dominated by species with unique trait combinations were typically larger‐bodied and less dispersive, and their loss would remove irreplaceable functional strategies from communities. Overall, our study reveals diverging long‐term trajectories of arthropod functional diversity across land uses, indicating potential negative consequences for ecosystem functioning in arable landscapes.

The world’s growing population raises concerns about future food security. At the same time, environmental challenges such as climate change, biodiversity loss, and the depletion of natural resources must be addressed, calling for a transformation of agriculture. This need is exacerbated by the limited availability of land suitable for arable farming. In this study, we examined the potential of agricultural land for arable farming and grassland use in Switzerland, under the premise that agricultural land use should align with the biophysical and environmental capacity of each location. In an iterative co-design process with scientists and public authorities, we elaborated three scenarios for agricultural transformation, which progressively incorporated (i) biophysical constraints (soil, climate, and topography) and (ii) environmental constraints (soil loss and eutrophication due to risk of erosion), as well as (iii) greenhouse gas emissions from drained organic soils. Our results show that the allocation of 40% arable land and 60% grassland in the most restrictive scenario closely resembles the current distribution (46% and 54%), respectively. However, the scenarios also revealed significant spatial shifts between arable land and grassland at the local level: only two-thirds of today’s arable land areas match their natural site conditions. Evidence from this study underscores the critical importance of site-adapted transitions of agricultural land use and the need for site-adapted management alternatives for farmland presently assigned to inadequate land use. Overall, this research provides a novel contribution by allowing the identification of hotspot areas for agricultural transformation at the local scale. We show that these site-specific land use analyses are essential for guiding effective land use planning and policy advice that strengthen the integrity of environmental performance and agricultural productivity, and support the development of targeted and sustainable land use strategies.

Insects are the most diverse and functionally important animals on Earth. In at least some regions, terrestrial populations are declining. Despite this, insects are often overlooked in conservation policy, and it is difficult to assess how anthropogenic threats and conservation actions affect insect populations. The Kunming‐Montreal Global Biodiversity Framework (GBF) aims to reduce pressures on biodiversity, increase conservation efforts, and reverse losses. At the International Congress on Conservation Biology in 2023, we convened a round table of specialist scientists and practitioners in insect ecology and conservation to explore how well the GBF addresses insect declines. We discussed and evaluated: (1) how well GBF targets could deliver for insects, and (2) whether the indicators proposed for monitoring progress would detect changes in the status of insects. We found that although the GBF's targets can drive action for insect recovery, almost none of the indicators can effectively measure progress for insects. We propose four principles to enhance the effectiveness of biodiversity policy for insects, and recommend the establishment of a global working group to develop insect‐focused indicators. If implemented effectively, such indicators could provide evidence of whether restoration and conservation actions are putting us on a path to recovery of global biodiversity.

Polarisation is a key process in land systems, describing land-change trajectories within a region that simultaneously move in opposite directions, such as co-occurring agricultural intensification and abandonment. Land-system polarisation relates strongly to sustainability goals, with potentially positive or negative consequences depending on domain and context. Yet, we lack approaches for mapping polarisation, limiting our understanding of its spatiotemporal distribution and integration into policy or impact assessments. We address this gap by exploring the concept of land-system polarisation and identifying five key dimensions for its mapping: spatial scales, temporal scales, land-use sectors, indicators, and neighbourhood relationships. We propose and test a workflow using the EU’s crop production systems, showing that ~ 87% of NUTS2 regions display polarisation. Our transferable workflow is adaptable across scales and contexts, enabling polarisation to serve as a lens for examining land-change drivers and impacts and providing spatially explicit information to guide targeted intervention and monitoring efforts.

Agroforestry systems integrate open and woody elements within agricultural landscapes, creating structurally complex ecosystems that provide habitats for diverse taxa, including spiders. This study examined the effect of agroforestry systems on ground-dwelling spiders across multiple European countries. In each country, several mature agroforestry plots were compared with non-agroforestry agricultural and woody reference plots. Our findings reveal that agroforestry supports species from both open and forested habitats, contributing to landscape-scale biodiversity. Alpha diversity was higher in silvopastures than in forests, but beta diversity (turnover) was not significantly different between agroforestry and other habitat types. Instead, there was a trend towards decreasing spider richness with increasing field size, across all habitat types. High variability in spider diversity across regions suggests that local environmental factors, such as tree species, management practices, and climate, play a key role in shaping spider communities. Our study supports that mosaic of small fields with diverse land uses, combined with seminatural habitats and structurally heterogeneous productive systems like agroforestry, can enhance biodiversity and species-rich agricultural landscapes.

The intensification of agricultural land use (A-LUI) is a central driver of global environmental change, affecting soil health, water quality, biodiversity, and greenhouse gas balances. Monitoring A-LUI remains challenging because it is shaped by multiple management practices, ecological processes, and spatio-temporal dynamics. This review provides a comprehensive synthesis of existing definitions and standards of A-LUI at national and international levels (FAO, OECD, World Bank, EUROSTAT) and evaluates in situ methods alongside the rapidly expanding potential of remote sensing (RS). We introduce a novel RS-based taxonomy of A-LUI indicators, structured into five complementary categories: trait, genesis, structural, taxonomic, and functional indicators. Numerous examples illustrate how traits and management practices can be translated into RS proxies and linked to intensity signals, while highlighting key challenges such as sensor limitations, cultivar variability, and confounding environmental factors. We further propose an integrative framework that connects management practices, plant and soil traits, RS observables, validation needs, and policy relevance. Emerging technologies—such as hyperspectral imaging, solar-induced fluorescence, radar, artificial intelligence, and semantic data integration—are discussed as promising pathways to advance the monitoring of A-LUI across scales. By compiling and structuring RS-derived indicators, this review establishes a conceptual and methodological foundation for transparent, standardised, and globally comparable assessments of agricultural land use intensity, thereby supporting both scientific progress and evidence-based agricultural policy.

Quantitative long‐term assessments of the extent and direction of biodiversity change due to anthropogenic environmental change are challenging because representative baseline data older than a few decades are very rare. This is also the case for grasslands in temperate Europe, which can harbour high species diversity at small spatial scales, but have undergone strong and varied changes, particularly in relation to the agricultural intensification that peaked in the middle of the last century. We resampled 416 historical vegetation records (originally sampled between 1884 and 1931) of 0.09 m ² from grasslands across Switzerland at a wide range of elevations (300–2500 m) and moisture levels to assess the changes in taxonomic, functional, and phylogenetic diversity, as well as community characteristics, and tested whether the magnitude of change depended on elevation. We found severe declines in alpha, beta, and gamma taxonomic diversity over the last century, with species richness being on average 26% lower in the resurvey plots than in the historical plots. Functional and phylogenetic alpha diversity were also lower in the resurvey plots than in the historical plots, although the differences were less pronounced. The loss in all three diversity metrics decreased with elevation. This was linked to stronger increases in nutrient‐demanding, mowing‐tolerant, and competitive species, particularly grasses (Poaceae), at lower than at higher elevations. This elevational pattern reflects the strong influences of land use and eutrophication, which are more pronounced at lower elevations. By contrast, the effect of global warming on vegetation has so far been subordinate. The smaller diversity changes at higher elevations offer the potential to maintain a high proportion of the historical plant diversity in mountain grasslands.