Ingolf Steffan-Dewenter

University of Wuerzburg | JMU · Department of Animal Ecology and Tropical Biology (Zoology III)

Citation: Dhillon, M.S.; Dahms, T.; Kübert-Flock, C.; Liepa, A.; Rummler, T.; Arnault, J.; Steffan-Dewenter, I.; Ullmann, T. Impact of STARFM on Crop Yield Predictions: Fusing MODIS with Landsat 5, 7, and 8 NDVIs in Bavaria Germany. Remote Sens. 2023, 15, 1651. https://www.mdpi.com/2072-4292/15/6/1651

Arthropods respond to vegetation in multiple ways since plants provide habitat and food resources and indicate local abiotic conditions. However, the relative importance of these factors for arthropod assemblages is less well understood. We aimed to disentangle the effects of plant species composition and environmental drivers on arthropod taxonomi...

In the tropics, smallholder farming characterizes some of the world's most biodiverse landscapes. Agroecology as a pathway to sustainable agriculture has been proposed and implemented in sub‐Saharan Africa, but the effects of agricultural practices in smallholder agriculture on biodiversity and ecosystem services are understudied. Similarly, the co...

In the tropics, combining food security with biodiversity conservation remains a major challenge. Tropical agroforestry systems are among the most biodiversity‐friendly and productive land‐use systems, and 70% of cocoa is grown by >6 million smallholder farmers living on <2$ per day. In cacao's main centre of diversification, the western Amazon reg...

The fast and accurate yield estimates with the increasing availability and variety of global satellite products and the rapid development of new algorithms remain a goal for precision agriculture and food security. However, the consistency and reliability of suitable methodologies that provide accurate crop yield outcomes still need to be explored....

Intensification of land use by humans has led to a homogenization of landscapes and decreasing resilience of ecosystems globally due to a loss of biodiversity, including the majority of forests. Biodiversity-ecosystem functioning (BEF) research has provided compelling evidence for a positive effect of biodiversity on ecosystem functions and service...

Understanding whether land use intensification causes regime shifts is of key importance for management, particularly if these shifts are associated with thresholds separating different ecosystem states and with hysteretic dynamics. Here we use a unique, long-term grassland database to identify thresholds in the response of 16 ecosystem functions a...

Global warming can increase insect pest pressure by enhancing reproductive rates. Whether this translates into yield losses, depends on phenological synchronisation of pests with their host plants and natural enemies. Simultaneously, landscape composition may mitigate climate effects by shaping the resource availability for pests and their antagoni...

Despite growing interest in gut microbiomes of aculeate Hymenoptera, research so far focused on social bees, wasps and ants, whereas non-social taxa and their brood parasites have not received much attention. Brood parasitism however allows to distinguish between microbiome components horizontally transmitted by spill-over from the host with such i...

The impact of local biodiversity loss on ecosystem functioning is well established, but the role of larger-scale biodiversity dynamics in the delivery of ecosystem services remains poorly understood. Here we address this gap using a comprehensive dataset describing the supply of 16 cultural, regulating and provisioning ecosystem services in 150 Eur...

The response of bee species to various stressors is assumed to depend on the availability of sufficient nutrients in their environment. We compare the response of three bee species (Apis mellifera, Bombus terrestris, Osmia bicornis) under laboratory conditions. Survival, physiology, and sensitivity, after exposure to the fungicide prochloraz, the i...

The negative impact of juvenile undernourishment on adult behavior has been well reported for vertebrates, but relatively little is known about invertebrates. In honeybees, nutrition has long been known to affect task performance and timing of behavioral transitions. Whether and how a dietary restriction during larval development affects the task p...

The mutualism between plants and pollinators is built upon the trophic ecology of flowers and florivores. Yet the ecology of flowers-as-food is left implicit in most studies of plant-pollinator ecology, and it has been largely neglected in mainstream trophic ecology. This deficit is especially evident in an emerging issue of basic and applied signi...

1. Pollination services from insects are important for higher yield and better fruit quality in avocado (Persea americana Mill.). Measuring pollinator effectiveness is significant for capturing the relative contributions of different insect taxa to pollination services and for identification of the most important pollinators of this globally import...

Dung beetles are important actors in the self-regulation of ecosystems by driving nutrient cycling, bioturbation, and pest suppression. Urbanization and the sprawl of agricultural areas, however, destroy natural habitats and may threaten dung beetle diversity. In addition, climate change may cause shifts in geographical distribution and community c...

Animals provide services such as pollination and pest control in cacao agro-forestry systems, but also disservices. Yet, their combined contributions to crop yield and fruit loss are mostly unclear. In a full-factorial field experiment in northwestern Peru, we excluded flying insects, ants, birds and bats from cacao trees and assessed several produ...

Recent studies link increased levels of ozone and carbon dioxide to plant performance and plant-herbivore interactions, but the interactive effects on plant-pollinator interactions and ecosystem services have rarely been studied. Here we experimentally tested whether elevated levels of these two gases alter plant growth, flower visitation, and yiel...

The exponential increase of the human population in tandem with increased food demand has caused agriculture to be the global‐dominant form of land use. Afrotropical drylands are currently facing the loss of natural savannah habitats and agricultural intensification with largely unknown consequences for bees. Here we investigate the effects of agri...

European honeybee populations are considered to consist only of managed colonies, but recent censuses have revealed that wild/feral colonies still occur in various countries. To gauge the ecological and evolutionary relevance of wild-living honeybees, information is needed on their population demography. We monitored feral honeybee colonies in Germ...

Abiotic factors are generally assumed to determine whether species can exist at the extreme ends of environmental gradients, for example, at high elevations, whereas the role of biotic interactions is less clear. On temperate mountains, insect-pollinated plant species with bilaterally symmetrical flowers exhibit a parallel elevational decline in sp...

Arthropod diversity in agricultural landscapes is important to maintain numerous ecosystem services. Most arthropods, however, need shelter habitats for overwintering embedded in agricultural landscapes. Habitats created by perennial agri-environmental schemes (AES) such as flowering fields can provide such overwintering places in addition to nesti...

Pollination services of cacao are crucial for global chocolate production, yet remain critically understudied, particularly in regions of origin of the species. Notably, uncertainties remain concerning the identity of cacao pollinators, the influence of landscape (forest distance) and management (shade cover) on flower visitation and the role of po...

Higher temperatures can increase metabolic rates and carbon demands of invertebrate herbivores, which may shift leaf-chewing herbivory among plant functional groups differing in C:N (carbon:nitrogen) ratios. Biotic factors influencing herbivore species richness may modulate these temperature effects. Yet, systematic studies comparing leaf-chewing h...

How can agroecological research methods effectively engage smallholder farmers, who provide over half of the world's food supply, and whose farm management activities have significant impacts on biodiversity and ecosystem services? This question is highly relevant in Malawi where the research took place, but in other low-income countries in Africa...

Changes in climate and land use are major threats to pollinating insects, an essential functional group. Here, we unravel the largely unknown interactive effects of both threats on seven pollinator taxa using a multiscale space-for-time approach across large climate and land-use gradients in a temperate region. Pollinator community composition, reg...

Arthropod predators are important for ecosystem functioning by providing top-down regulation of insect herbivores. As predator communities and activity are influenced by biotic and abiotic factors on different spatial scales, the strength of top-down regulation ('arthropod predation') is also likely to vary. Understanding the combined effects of po...

Land-use intensification and climate change threaten ecosystem functions. A fundamental, yet often overlooked, function is decomposition of necromass. The direct and indirect anthropogenic effects on decomposition, however, are poorly understood. We measured decomposition of two contrasting types of necromass, rat carrion and bison dung, on 179 stu...

Environmental gradients generate and maintain biodiversity on Earth. Mountain slopes are among the most pronounced terrestrial environmental gradients, and the elevational structure of species and their interactions can provide unique insight into the processes that govern community assembly and function in mountain ecosystems. We recorded bumble b...

The composition and richness of herbivore and plant assemblages change along climatic gradients, but knowledge about associated shifts in specialisation is scarce and lacks controlling for the abundance and phylogeny of interaction partners. Thus, we aimed to test whether the specialisation of phytophagous insects in insect ‐ plant – interaction ne...

The contribution of seasonality in species communities to elevational diversity of tropical insects remains poorly understood. We here assessed seasonal patterns and drivers of bee diversity in the Eastern Afromontane Biodiversity Hotspot, Kenya, to understand the contribution of seasonality to elevational biodiversity patterns. Bee species and pla...

Larger geographical areas contain more species—an observation raised to a law in ecology. Less explored is whether biodiversity changes are accompanied by a modification of interaction networks. We use data from 32 spatial interaction networks from different ecosystems to analyse how network structure changes with area. We find that basic community...

Livestock grazing is widespread and increasing in the African grasslands, with largely unknown consequences for bee pollinators. Here we assessed the direct and indirect impacts of livestock grazing intensity on bee assemblages in East African grasslands and tested if the effect of grazing intensity on bee assemblages depends on temperature. We col...

Societal Impact Statement Pollen relates to many aspects of human and environmental health, which protection and improvement are endorsed by the United Nations Sustainable Development Goals. By highlighting these connections in the frame of current challenges in monitoring and research, we discuss the need of more integrative and multidisciplinary...

Arthropod predators are important for ecosystem functioning by providing top-down regulation of insect herbivores. As predator communities and activity are influenced by biotic and abiotic factors on different spatial scales, the strength of top-down regulation (‘arthropod predation’) is also likely to vary. Understanding the combined effects of po...

The monitoring of species and functional diversity is of increasing relevance for the development of strategies for the conservation and management of biodiversity. Therefore, reliable estimates of the performance of monitoring techniques across taxa become important. Using a unique dataset, this study investigates the potential of airborne LiDAR-d...

Agricultural expansion and intensification increasingly threaten birds and bats, especially insectivorous species from the tropics. Cacao agroforests in tropical rainforest areas have been shown to support higher bird and bat biodiversity than other land-use systems, but their suitability for tropical dry forest biodiversity remains unclear. We pre...

The diversity of endemic honeybee subspecies and ecotypes is at risk in Europe because modern apiculture promotes only a small number of honeybee strains. A crucial step for the conservation of honeybee diversity is the assessment of the status of remaining wild populations and their limiting factors. Here we present a two-year census of native, wi...

The increasing availability and variety of global satellite products provide a new level of data with different spatial, temporal, and spectral resolutions; however, identifying the most suited resolution for a specific application consumes increasingly more time and computation effort. The region's cloud coverage additionally influences the choice...

Deforestation drives climate change and reinforces food insecurity in forest‐dependent communities. What drives deforestation varies by location and is shaped by livelihood systems. But how locals perceive restoration is crucial for developing restoration policies. Evidence suggests that applying sustainable farming strategies can potentially resto...

• Among the many concerns for biodiversity in the Anthropocene, recent reports of flying insect loss are particularly alarming, given their importance as pollinators, pest control agents, and as a food source. Few insect monitoring programmes cover the large spatial scales required to provide more generalizable estimates of insect responses to glob...

In vitro rearing of honeybee larvae is an established method that enables exact control and monitoring of developmental factors and allows controlled application of pesticides or pathogens. However, only a few studies have investigated how the rearing method itself affects the behavior of the resulting adult honeybees. We raised honeybees in vitro...

Patterns of resource use by animals can clarify how ecological communities have assembled in the past, how they currently function and how they are likely to respond to future perturbations. Bumble bees (Hymentoptera: Bombus spp.) and their floral hosts provide a diverse yet tractable system in which to explore resource selection in the context of...

Exposure of plants to environmental stressors can modify their metabolism, interactions with other organisms and reproductive success. Tropospheric ozone is a source of plant stress. We investigated how an acute exposure to ozone at different times of plant development affects reproductive performance, as well as the flowering patterns and the inte...

Many experiments have shown that biodiversity enhances ecosystem functioning. However, we have little understanding of how environmental heterogeneity shapes the effect of diversity on ecosystem functioning and to what extent this diversity effect is mediated by variation in species richness or species turnover. This knowledge is crucial to scaling...

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, w...

Climate and land‐use change are key drivers of environmental degradation in the Anthropocene, but too little is known about their interactive effects on biodiversity and ecosystem services. Long‐term data on biodiversity trends are currently lacking. Furthermore, previous ecological studies have rarely considered climate and land use in a joint des...

Interactions between plants and herbivorous invertebrates drive the nutritional quality of resources for higher trophic levels, nutrient cycling and plant-community structure. Thereby, shifts in functional composition of plant communities particularly impact ecosystem processes. However, the current understanding of herbivory is limited concerning...

Recently reported insect declines have raised both political and social concern. Although the declines have been attributed to land use and climate change, supporting evidence suffers from low taxonomic resolution, short time series, a focus on local scales, and the collinearity of the identified drivers. In this study, we conducted a systematic as...

Pollen beetles (Brassicogethes spp.) are the main pests of oilseed rape (OSR, Brassica napus) in Europe and responsible for massive yield losses. Upcoming pesticide resistances highlight the need for other means of crop protection, such as natural pest control. Sown flower fields aim to counteract the decrease of insect biodiversity in agricultural...

Sub-Saharan African crop production largely relies on smallholder farms, located both in urban and agricultural landscapes. In this context, the investigation of plant and pollinator diversity and their interactions is of primary importance since both these factors are threatened by land use intensification and the consequent loss of natural habita...

Honey bee health is affected by multiple stressors, such as the exposure to plant protection products (PPPs), dietary limitation, monofloral diets and pressure of diseases and pathogens and their interactions. Here, we analysed the interacting effects of plant protection products and low nutritional pollen source on honey bee health under semi-fiel...

Patterns of insect diversity along elevational gradients are well described in ecology. However, it remains little tested how variation in the quantity, quality, and diversity of food resources influence these patterns. Here we analyzed direct and indirect effects of climate, food quantity (estimated by net primary productivity), quality (variation...

Background: Bees (Hymenoptera: Apoidea: Anthophila) are the most important group of pollinators with about 20,507 known species worldwide. Despite the critical role of bees in providing pollination services, studies aiming at understanding which species are present across disturbance gradients are scarce. Limited taxononomic information for the ex...