Papers by Christoph Scherber
Dendrogram representing the relationships between the 60 species present in the Jena Experiment b... more Dendrogram representing the relationships between the 60 species present in the Jena Experiment based on functional traits.
Maximum clade-credibility phylogeny of the 60 species in the Jena Experiment.
Standardized and unstandardized maximum-likelihood estimates for the minimal adequate structural ... more Standardized and unstandardized maximum-likelihood estimates for the minimal adequate structural equation models.
Nutrition is the single most important factor for individual's growth and reproduction. Conse... more Nutrition is the single most important factor for individual's growth and reproduction. Consequently, the inability to reach the nutritional optimum imposes severe consequences for animal fitness. Yet, under natural conditions, organisms may face a mixture of stressors that can modulate the effects of nutritional asymmetry. For instance, stressful environments caused by intense interaction with conspecifics. Here, we subjected the house cricket <i>Acheta domesticus</i> to (i) either of two types of diet that have proved to affect cricket performance and (ii) simultaneously manipulated their social environment throughout their complete life cycle. We aimed to track sex-specific consequences for multiple traits during insect development throughout all life stages. Both factors affected critical life-history traits with potential population-level consequences: diet composition induced strong effects on insect development time, lifespan and fitness, while the social envi...
and processes—eight hypotheses. Biol Rev
Global Change Biology, 2018
Closing yield gaps within existing croplands, and thereby avoiding further habitat conversions, i... more Closing yield gaps within existing croplands, and thereby avoiding further habitat conversions, is a prominently and controversially discussed strategy to meet the rising demand for agricultural products, while minimizing biodiversity impacts. The agricultural intensification associated with such a strategy poses additional threats to biodiversity within agricultural landscapes. The uneven spatial distribution of both yield gaps and biodiversity provides opportunities for reconciling agricultural intensification and biodiversity conservation through spatially optimized intensification. Here, we integrate distribution and habitat information for almost 20,000 vertebrate species with land-cover and land-use datasets. We estimate that projected agricultural intensification between 2000 and 2040 would reduce the global biodiversity value of agricultural lands by 11%, relative to 2000. Contrasting these projections with spatial land-use optimization scenarios reveals that 88% of projected biodiversity loss could be avoided through globally coordinated land-use planning, Accepted Article This article is protected by copyright. All rights reserved. implying huge efficiency gains through international cooperation. However, global-scale optimization also implies a highly uneven distribution of costs and benefits, resulting in distinct 'winners and losers' in terms of national economic development, food-security, foodsovereignty or conservation. Given conflicting national interests and lacking effective governance mechanisms to guarantee equitable compensation of losers, multinational landuse optimization seems politically unlikely. In turn, 61% of projected biodiversity loss could be avoided through nationally-focused optimization, and 33% through optimization within just 10 countries. Targeted efforts to improve the capacity for integrated land-use planning for sustainable intensification especially in these countries, including the strengthening of institutions that can arbitrate sub-national land-use conflicts, may offer an effective, yet politically feasible, avenue to better reconcile future trade-offs between agriculture and conservation. The efficiency gains of optimization remained robust when assuming that yields could only be increased to 80% of their potential. Our results highlight the need to better integrate real-world governance, political and economic challenges into sustainable development and global change mitigation research.
Journal of Applied Ecology, 2018
This is the author manuscript accepted for publication and has undergone full peer review but has... more This is the author manuscript accepted for publication and has undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process, which may lead to differences between this version and the Version of Record. Please cite this article as
Oecologia, Jan 25, 2015
Agricultural intensification has been shown to reduce biodiversity through processes such as habi... more Agricultural intensification has been shown to reduce biodiversity through processes such as habitat degradation and fragmentation. We tested whether several small or single large habitat fragments (re-visiting the 'single large or several small' debate) support more species across a wide range of taxonomic groups (plants, leafhoppers, true bugs, snails). Our study comprised 14 small (<1 ha) and 14 large (1.5-8 ha) fragments of calcareous grassland in Central Germany along orthogonal gradients of landscape complexity and habitat connectivity. Each taxon was sampled on six plots per fragment. Across taxa, species richness did not differ between large and small fragments, whereas species-area accumulation curves showed that both overall and specialist species richness was much higher on several small fragments of calcareous grassland than on few large fragments. On average, 85 % of the overall species richness was recorded on all small fragments taken together (4.6 ha), whe...
Diversity and Distributions, 2015
Aim Biodiversity across the globe is heavily eroded by intensified management at local and landsc... more Aim Biodiversity across the globe is heavily eroded by intensified management at local and landscape scales. Species communities of calcareous grasslands, which are among Europe's most diverse habitats, are severely threatened by the cessation of appropriate traditional management, loss of habitat connectivity and simplification of the surrounding landscape. However, our understanding of these often interrelated factors remains limited, in particular for trait-mediated responses across taxa. Here, we test the independent effects of local management (grazing, mowing and abandonment), habitat connectivity (measured by a connectivity index) and landscape complexity (indicated by the percentage of arable land) on nine taxa: plants, butterflies, bees, grasshoppers, hoverflies, spiders, true bugs, rove beetles and leafhoppers on small semi-natural calcareous grassland remnants (< 1 ha). Location Central Germany. Methods We use a joint analysis across taxa to identify general and trait-mediated responses (body size and Red List status) in species richness, abundance and community composition. Results We identified three key drivers of local diversity patterns: First, an increasing proportion of arable land from 10% to 80% led to a 29% loss of overall species richness. Second, despite differences between taxa, increasing habitat connectivity generally enhanced species richness. Connectivity effects were more accentuated in the large species per taxon, which can be expected to be good dispersers. Finally, grazing reduced species richness and abundance much more than annual mowing or short-term abandonment (5-15 years), in particular for red-listed species. We attribute this to plant resource removal through overgrazing and trampling. Main conclusions For the conservation management of small calcareous grasslands, we advocate an alternating strategy of mowing or lenient grazing and short-term abandonment, prioritizing connected fragments surrounded by diverse landscapes. Despite taxon-specific responses, our study across nine taxa demonstrates universal, trait-mediated effects of management, landscape complexity and connectivity on local biodiversity in fragmented communities.
Forest Ecology and Management, 2014
Habitat fragmentation is a major driver of species loss. Here we test the hypotheses that high tr... more Habitat fragmentation is a major driver of species loss. Here we test the hypotheses that high tree diversity in a large deciduous forest enhances bird diversity and nest survival. We further expect that forest edges support higher bird diversity when different habitat types adjoin, whereas nest predation is not higher, because the large forest area mitigates potential edge effects. We studied how edge-centre differences and tree diversity (beech-dominated vs. tree-species rich) affect the bird community and survival rates of ground breeding birds' nests based on an artificial nest predation experiment in the Hainich National Park, Germany. We surveyed birds three times during the breeding season. We selected six forest stands with low tree diversity (i.e. dominated by beech) and six with high tree diversity (i.e. tree-species rich). Each forest stand contained four bird survey plots (plot 1: 0-30 m, plot 2: 60-90 m, plot 3: 120-150 m and plot 4: 180-210 m distant from edge; altogether 48 bird survey plots). Additionally each plot corner contained one artificial ground nest baited with one Blue-breasted Quail egg and one plasticine egg for eight days of exposure in the middle of the breeding season. Bird abundance and diversity were higher in the first 30 m of the forest. Bird diversity, including ground breeding birds, was also enhanced by higher percentages of bushes, which can provide enhanced food supply, perches as well as sheltering. Nest predation showed no edge effect, supporting the idea that small area of forest fragments causes more important negative effects than the edge in large forest remnants. Predation rates were higher in tree-species rich stands compared to beech-dominated stands, probably due to greater diversity and density of mammalian predators. Edge effects shaped the bird community composition and positively affected abundances of tree and shrub breeding birds, but did not affect ground breeders and the nest predation of ground nests. Shrub breeders accumulating in forest edges might, however, suffer more from nest predation in forest fragments. In conclusion, bird diversity and avian egg predation were affected by both forest edges and tree diversity in surprisingly different ways.
Innovations in Landscape Research, 2021
Due to the multiplicity of challenges facing all societies at the beginning of the twenty-first c... more Due to the multiplicity of challenges facing all societies at the beginning of the twenty-first century, agricultural systems and rural landscapes are under pressure. Solutions for their optimization towards sustainability at high productivity are required. We address the majority of current agricultural systems and discuss approaches for assessing their sustainability. Life cycle analyses and footprint methods have experienced much progress but require further qualification. Some alternative farming systems such as organic agriculture, agroecology, regenerative agriculture, ecological intensification, and sustainable intensification, which are based on landscape approaches and direct farmer–consumer interactions have potential for significant improvements towards the sustainability of global agriculture and need further attention and promotion in research and practice. Technology-driven smart farming technologies can be implemented in all these kinds of farming systems. A key to preventing the degradation of agricultural landscapes and improving ecology and economics lies in their better structural development and design, adapted to geosystem settings, legacies of local cultural history and opportunities presented by urban–rural interactions. For achieving better landscape design, it is worth thinking about reforming and strengthening land consolidation as a planned participatory process involving the rural community. Further, scientifically sound and policy relevant rules and steering instruments have to be developed for the design and cultural evolution of rural landscapes. The European Union (EU) and other wealthy economic zones, federations, countries, and regions have developed funding systems for agriculture. The Common Agricultural Policy (CAP) of the EU is a powerful tool promoting both the possession and ownership of agricultural land (pillar I, main pillar) and rural development (pillar II). This system should be better balanced by shifting towards pillar II to promote further ecosystem services in agricultural regions. Novel solutions should be aimed at for maintaining landscape diversity and heritage, developing local food cultures and agritourism, and strengthening rural communities and their societal image. Transdisciplinary international model projects are useful contributions to making innovations operable.
Landscape Ecology, 2014
ABSTRACT Current biodiversity conservation policies have so far had limited success because they ... more ABSTRACT Current biodiversity conservation policies have so far had limited success because they are mainly targeted to the scale of individual fields with little concern on different responses of organism groups at larger spatial scales. We investigated the relative impacts of multi-scale factors, including local land use intensity, landscape context and region, on functional groups of beetles (Coleoptera). In 2008, beetles were suction-sampled from 95 managed grasslands in three regions, ranging from Southern to Northern Germany. The results showed that region was the most important factor affecting the abundance of herbivores and the abundance and species composition of predators and decomposers. Herbivores were not affected by landscape context and land use intensity. The species composition of the predator communities changed with land use intensity, but only in interaction with landscape context. Interestingly, decomposer abundance was negatively related to land use intensity in low-diversity landscapes, whereas in high-diversity landscapes the relation was positive, possibly due to enhanced spillover effects in complex landscapes. We conclude that (i) management at multiple scales, from local sites to landscapes and regions, is essential for managing biodiversity, (ii) beetle predators and decomposers are more affected than herbivores, supporting the hypothesis that higher trophic levels are more sensitive to environmental change, and (iii) sustaining biological control and decomposition services in managed grassland needs a diverse landscape, while effects of local land use intensity may depend on landscape context.
Environmental Science and Engineering, 2010
ContextBiodiversity monitoring programs require fast, reliable and cost-effective methods for bio... more ContextBiodiversity monitoring programs require fast, reliable and cost-effective methods for biodiversity assessment in landscapes. Sampling pollinators across entire landscapes is challenging, as trapping needs to cover many habitat types.ObjectivesWe developed and tested a landscape-wide sampling design for pollinators. We assessed the predictability and stability of pollinator biodiversity estimates in agricultural landscapes, and tested how estimates were affected by sampled habitat, landscape composition and spatial scale.MethodsWe sampled pollinators using pan traps at 250 locations in 10 replicated landscapes measuring 1 × 1 km and calculated bee richness predictions based on different sample sizes. Traps were placed regularly in each landscape, sampling each habitat proportionally to its area. Landscapes contained semi-natural habitats, crop fields and forests and differed in the amount of a mass-flowering crop (oilseed rape).ResultsRegular sampling reflected local habitat ...
Innovations in Landscape Research
Most vegetated land on earth has been used for agriculture for hundreds of years, shaping the lan... more Most vegetated land on earth has been used for agriculture for hundreds of years, shaping the land's features and functions. Agricultural (rural) landscapes are the basis for feeding the global population and meeting their many other demands. In the globalised world of the twenty-first century, agriculture is facing some crucial challenges: feeding more people whilst maintaining natural resources, biodiversity and landscape heritage, and mitigating climate Abdulla Saparov died of COVID-19 in 2020. The team of editors and authors mourns the loss of a highly esteemed scientist and will preserve his scientific legacy.
Innovations in Landscape Research
Reports on recent declines in insect biodiversity have prompted discussions on how to assess inse... more Reports on recent declines in insect biodiversity have prompted discussions on how to assess insect species numbers across a wide range of different habitats and on large spatial scales. Previous approaches were often restricted to particular habitat types (such as calcareous grasslands) or taxa (such as butterflies). Here, we show that setting up insect traps along regular sampling grids (25 grid cells) in replicate 1 Â 1 km landscapes allows sampling insect biodiversity across all habitat types in changing landscapes and for a wide range of taxa and functional groups, including herbivores, predators and pollinators. If combined with remote sensing and image classification workflows, our approach allows powerful conclusions on inter-and intra-annual dynamics of insects in agricultural landscapes that are often highly dynamic due to crop rotations. The number of samples obtained in each habitat closely follows the landscape-wide amount of each habitat type. Hence, the sampling scheme is suitable to compare insect populations and communities in different habitats according to the true habitat amount. Our approach complements the existing approaches of how landscape structure affects populations in a given habitat and is useful for long-term biodiversity monitoring.
Advances in Understanding Soil Degradation
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Papers by Christoph Scherber