Ingo Grass

Ingo Grass
University of Hohenheim · Ecology of Tropical Agricultural Systems

PhD

About

94
Publications
65,376
Reads
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Citations
Introduction
We study the biodiversity, species interactions and ecosystem services of tropical and temperate agricultural landscapes. We strive to better understand the processes shaping plant and animal communities as well as their interactions in agroecosystems, including drivers acting at local and landscape scale. Our aim is the development of novel farming practices that promote agricultural productivity, while sustaining biodiversity, functioning and services of ecosystems.
Additional affiliations
October 2019 - present
University of Hohenheim
Position
  • Professor (Full)
September 2014 - September 2019
Georg-August-Universität Göttingen
Position
  • PostDoc Position
August 2011 - August 2014
Philipps-Universität Marburg
Position
  • Research Assistant
Education
August 2011 - March 2014
Philipps-Universität Marburg
Field of study
  • Biology

Publications

Publications (94)
Article
Full-text available
Urbanization is a major driver of land use change and biodiversity decline. While most of the ongoing and future urbanization hot spots are located in the Global South, the impact of urban expansion on agricultural biodiversity and associated functions and services in these regions has widely been neglected. Additionally, most studies assess biodiv...
Article
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To understand how plant-pollinator interactions respond to habitat fragmentation, we need novel approaches that can capture properties that emerge at broad scales, where multiple communities engage in metanetworks. Here we studied plant-pollinator interactions over 2 years on 29 calcareous grassland fragments selected along independent gradients of...
Article
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Significance Finding entry points where policy has strong leverage to transform land systems for people and nature is pivotal. We develop an innovative framework to identify and evaluate such leverage points along land-use trajectories that account for path dependency. Applied to the biodiversity hotspot Madagascar, the framework reveals three leve...
Article
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Extreme events, such as those caused by climate change, economic or geopolitical shocks, and pest or disease epidemics, threaten global food security. The complexity of causation, as well as the myriad ways that an event, or a sequence of events, creates cascading and systemic impacts, poses significant challenges to food systems research and polic...
Article
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Resolving ecological-economic trade-offs between biodiversity and yields is a key challenge when addressing the biodiversity crisis in tropical agricultural landscapes. Here, we focused on the relation between seven different taxa (trees, herbaceous plants, birds, amphibians, reptiles, butterflies, and ants) and yields in vanilla agroforests in Mad...
Article
Natural habitat plays a role in many agroecosystems as a source of pollination services and other ecological spillover, but these effects are largely unquantified in oil palm (Elaeis guineensis), a globally important crop linked to deforestation. In a field experiment in Sumatra, Indonesia, we manipulated floral visitor access to female oil palm in...
Article
How urbanization affects crop pollination has scarcely been studied, especially in the tropics. Here, we focus on the richness and abundance of wild bees and their pollination services to 30 small-scale fields of Lablab purpureus, a globally wide-spread grain legume, in the Indian megacity Bangalore. Farms were selected along a gradient of urbaniza...
Article
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Urbanization is a major threat to biodiversity and food security, as expanding cities, especially in the Global South, increasingly compete with natural and agricultural lands. However, the impact of urban expansion on agricultural biodiversity in tropical regions is overlooked. Here we assessed how urbanization affects the functional response of f...
Article
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Background Intense conversion of tropical forests into agricultural systems contributes to habitat loss and the decline of ecosystem functions. Plant-pollinator interactions buffer the process of forest fragmentation, ensuring gene flow across isolated patches of forests by pollen transfer. In this study, we identified the composition of pollen gra...
Article
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1. The conversion of tropical forests into agriculture reduces biodiversity dramatically. However, species might differ in their responses, depending on their habitat specialisation and geographic origin. In this study, we assess how butterfly assemblages differ between old-growth forests, forest fragments, forest-derived vanilla agroforests, fallo...
Article
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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...
Article
In their response to our paper on harnessing biodiversity in agricultural landscapes [1], Stein-Bachinger et al. [2] argue that our statements in favour of reducing field size and crop diversification ‘have to be combined with reduced management intensity’ to be effective. While we acknowledge the role of reducing agricultural intensity for biodive...
Article
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1. Conventional agriculture in the global north is typically characterized by large monocultures, commonly managed with high levels of pesticide or fertilizer input and mechanization. Strip‐intercropping, i.e., diversifying cropland by growing strips of different crops using conventional machinery, may be a viable strategy to promote natural predat...
Article
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Understanding how land-use change affects biodiversity is a fundamental step to develop effective conservation strategies in human-modified tropical landscapes. Here, we analyzed how land-use change through tropical small-scale agriculture affects endemic, exotic, and non-endemic native ant communities, focusing on vanilla landscapes in northeaster...
Article
In their response to our paper on harnessing biodiversity-friendly landscapes [1], Brühl et al. [2] argue that we underestimate the benefits of banning synthetic pesticides in organic farming. We thank the authors for highlighting the importance of reducing pesticide applications for biodiversity conservation, an assessment that we share [3–5]. How...
Article
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Wildflower plantings are an important mitigation tool within agri-environmental schemes to counter insect decline in resource-scarce agricultural landscapes. Effectiveness of wildflower plantings for insect conservation is typically studied at the community or species level. It is the individual, however, that is subject to changing abiotic and bio...
Chapter
Urban areas are increasing in number and extent worldwide. Few other anthropogenic land uses alter landscapes in a more persistent fashion; however, the effects of urbansiation on biodiversity remain poorly studied. Here, we studied bird communities along the rural–urban interface of the Indian megacity Bengaluru. Birds were assessed with point cou...
Article
Bats have been shown to provide successful pest suppression in different land-use systems globally. Recent research demonstrates high economic values of pest suppression by bats also in macadamia orchards, which is enhanced by natural habitat patches at orchard edges. We investigated the impact of the conversion of natural to agricultural (macadami...
Article
We challenge the widespread appraisal that organic farming is the fundamental alternative to conventional farming for harnessing biodiversity in agricultural landscapes. Certification of organic production is largely restricted to banning synthetic agrochemicals, resulting in limited benefits for biodiversity but high yield losses despite ongoing i...
Article
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Agroforestry can contribute to an increase in tree cover in historically forested tropical landscapes with associated gains in biodiversity and ecosystem functioning, but only if established on open land instead of underneath a forest canopy. However, declines in yields with increasing shade are common across agroforestry crops, driving shade-tree...
Article
Global pollinator declines and land-use change can lead to pollination limitation with implications for agricultural productivity. Hand pollination is used in agricultural production as a technique to manually pollinate crops. But the prevalence of hand pollination, as well as benefits and costs, remain unknown. We systematically reviewed the liter...
Article
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Aim: Northeastern Madagascar is a hotspot of plant diversity, but vanilla and rice farming are driving land-use change, including slash-and-burn management. It still remains unknown how land-use change and land-use history affect richness and composition of endemic, native and exotic herbaceous plant species. Location: Northeastern Madagascar. Me...
Article
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Pollinator declines in agricultural landscapes are driven by multiple stressors, but potential interactions of these remain poorly studied. Using a highly replicated semi-field study with 56 meso-cosms of varying wild plant diversity (2-16 species) and oilseed rape treated with a neonicotinoid, we tested the interacting effects of resource diversit...
Preprint
Full-text available
Quantifying how multiple ecosystem services and functions are affected by different drivers of Global Change is challenging. Particularly in African savanna regions, highly integrated land-use activities created a landscape mosaic with flows of multiple resources between land use types. A framework is needed that quantifies the effects of climate c...
Article
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In Central Europe, agricultural intensification has led to increasing fragmentation and loss of semi-natural habitats. In turn, ecosystem services such as pollination are being lost when insect pollinators depend on semi-natural habitats. Calcareous grasslands are a highly threatened, biodiverse type of semi-natural habitat that may substantially s...
Article
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Aim It is widely accepted that biodiversity is influenced by both niche‐related and spatial processes from local to global scales. Their relative importance, however, is still disputed, and empirical tests are surprisingly scarce at the global scale. Here, we compare the importance of area (as a proxy for pure spatial processes) and environmental h...
Article
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1. Many insect species provide essential pollination services. However, the amount of pollen deposited onto a stigma when visiting a flower (“single visit pollen deposition”, SVD) can vary greatly among taxa depending on morphological traits of pollinators. Further, SVD is commonly measured using one of two methods (‘static’: waiting for an insect...
Article
Reconciling biodiversity conservation with increasing demand for agricultural production is a major challenge. A long-running discourse that addresses this challenge is the land-sparing vs land-sharing debate. However, the land-sparing vs land-sharing framework has also been criticized for favouring a dichotomous worldview, which contradicts the re...
Article
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Rising global demand for vegetable oil during the last few decades has led to a drastic increase in the area under oil palm. Especially in Southeast Asia, the oil palm boom has contributed to economic growth, but has also spurred criticism about negative environmental and social effects. Here, we discuss palm oil production and consumption trends a...
Article
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Rising global demand for vegetable oil during the last few decades has led to a drastic increase in the land area under oil palm. Especially in Southeast Asia, the oil palm boom has contributed to economic growth, but it has also spurred criticism about negative environmental and social effects. Here, we discuss palm oil production and consumption...
Article
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1. Land-use change is the main driver of deforestation and land degradation resulting in the loss of biodiversity and ecosystem functioning in northeastern Madagascar. Vanilla, the region's main cash crop, is grown in agroforestry systems and may provide an opportunity for the conservation of biodiversity and ecosystem functioning. 2. We used dummy...
Preprint
Full-text available
Agroforestry can contribute to an increase in tree cover in historically forested tropical landscapes with associated gains in biodiversity and ecosystem functioning, but only if established on open land instead of inside forest. However, trade-offs between shade and crop yields are common across many agroforestry crops, driving shade-tree loss in...
Article
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Agroforestry is widely promoted as a potential solution to address multiple UN Sustainable Development Goals, including Zero Hunger, Responsible Consumption and Production, Climate Action, and Life on Land. Nonetheless, agroforests in the tropics often result from direct forest conversions, displacing rapidly vanishing and highly biodiverse forests...
Article
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European nature conservation has a strong focus on farmland harbouring threatened species that mainly co-occur with traditional agriculture shaped way before the green revolution. Increased land-use intensity in agriculture has caused an alarming decline in farmland biodiversity during the last century. How can a landscape perspective contribute to...
Article
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Habitat loss and landscape fragmentation are important drivers of changes in biodiversity. In fragmented landscapes, bird species are able to use multiple forest patches that may therefore share an important portion of the regional biodiversity. In turn, these patches are linked through their shared bird diversity (i.e. species-habitat networks). I...
Article
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• Local land‐use intensity and surrounding landscape complexity affect the diversity of local species. Ants are an important biocontrol agent of the coffee berry borer (CBB), the main coffee pest worldwide. Although intensification of coffee production and deforestation in the surrounding landscape may reduce ant diversity, α‐ and β‐diversity patte...
Article
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Die moderne Intensivlandwirtschaft verantwortet maßgeblich den anhaltenden Biodiversitätsverlust. Zugleich ist Naturschutz ohne Landwirtschaft unmöglich. Eine Diversifizierung der Landwirtschaft und Agrarlandschaften ist erforderlich, von der Mensch und Natur profitieren.
Article
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Land-use transitions can enhance the livelihoods of smallholder farmers but potential economic-ecological trade-offs remain poorly understood. Here, we present an interdisciplinary study of the environmental, social and economic consequences of land-use transitions in a tropical smallholder landscape on Sumatra, Indonesia. We find widespread biodiv...
Article
Urban areas are growing worldwide and alter landscapes in a persistent fashion, thereby affecting biodiversity and ecosystem services such as pollination in a little understood way. Here we present a systematic review of the peer-reviewed literature to identify the drivers of urban pollinator populations and pollination. A total of 141 studies were...
Article
Full-text available
Oil palm plantations are intensively managed agricultural systems that increasingly dominate certain tropical regions. Oil palm monocultures have been criticized because of their reduced biodiversity compared to the forests they historically replaced, and because of their negative impact on soils, water, and climate. We experimentally test whether...
Chapter
Biodiversity-ecosystem functioning (BEF) research grew rapidly following concerns that biodiversity loss would negatively affect ecosystem functions and the ecosystem services they underpin. However, despite evidence that biodiversity strongly affects ecosystem functioning, the influence of BEF research upon policy and the management of ‘real-world...
Article
Autonomous sound recording techniques have gained considerable traction in the last decade, but the question remains whether they can replace human observation surveys to sample sonant animals. For birds in particular, survey methods have been tested extensively using point counts and sound recording surveys. Here, we review the latest evidence for...
Article
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The loss of roost sites is one of the major drivers of the worldwide decline in bat populations and roost site preferences, either natural or artificially provided, are not well known for African bat species specifically. In this study we focus on the preference for different artificial roost sites by insectivorous bats in macadamia orchards in nor...
Article
1.The relative importance of ecosystem services and disservices can change with landscape structure in a poorly understood way. 2.We compare the impact of biocontrol, provided by bats and birds, with that of crop raiding by vervet monkeys on yield in South African macadamia orchards. Insectivorous bats and birds are known to feed on macadamia pest...
Article
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This study examines conservation effects of wildlife trade using demand and supply data from caged-bird markets in Sumatra, Indonesia. When consumers have a strong preference for species rarity, trade could result in wildlife overexploitation and species extinction. Results from a choice experiment show that buyers of caged birds indeed value speci...
Article
Riparian forests, an integral part of savanna ecosystems, are threatened across West Africa by agricultural expansion. However, some patches of original riparian vegetation are protected by traditional beliefs as ‘Sacred Groves’. We assessed the role of Sacred Groves in maintaining landscape-scale bird assemblages by conducting 144 1-h point counts...
Article
Coffee is one of the most important commodities globally and the Coffee Berry Borer (CBB) is its main pest, causing losses of more than half a billion dollars annually. In this systematic review, we quantify the available evidence of successful biological control in coffee agroforestry. There is a recent research trend of switching from the traditi...
Article
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1. The land-sharing versus land-sparing debate recently stagnated, lacking an integrating perspective in agricultural landscapes as well as consideration of ecosystem services. Here, we argue that land-sharing (i.e. wildlife-friendly farming systems) and land-sparing (i.e. separation of high-yielding agriculture and natural habitats) are not mutual...
Presentation
Cash crops farmed in agroforestry systems can be an economically attractive opportunity for farmers that are potentially ecologically sustainable alleviating negative impacts on biodiversity and ecosystem functions. Whether such a win-win situation can be realised is, however, highly context-dependent. Here, we study the impacts of vanilla agrofore...
Article
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The diet of insectivorous bat species is difficult to study and the least invasive tool to gain information on these predators’ foraging preferences is the study of their faecal pellets.The aim of this study was to determine whether bats consumed insect pest species in macadamia orchards, with the additional goal of incentivising farmers to adopt a...
Article
Experimental exclosure of birds and bats constitutes a powerful tool to study the impacts of wildlife on pests and crop yields in agricultural systems. Though widely utilized, exclosure experiments are not standardized across studies. Indeed, key differences surrounding the design, materials, and protocols for implementing field-based exclosure exp...
Article
The risk of ecosystem function degradation with biodiversity loss has emerged as a major scientific concern in recent years. Possible relationships between taxonomic diversity and magnitude and stability of ecosystem processes build upon species’ functional characteristics, which determine both susceptibility to environmental change and contributio...
Article
Animal pollinators are in a serious decline due to habitat loss, isolation and landscape fragmentation, putting pollination services to crops at risk. Hedgerows have been repeatedly emphasized as landscape elements that provide nesting and food resources, connect fragmented habitats and could thus facilitate crop pollination. However, the beneficia...
Chapter
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Forty-four percent of Europe’s terrestrial surface is covered with agricultural land. Thus, agriculture strongly influences Europe’s environment, including ecological functions and processes.
Article
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Aim Biogeographical comparisons of interaction networks help to elucidate differences in ecological communities and ecosystem functioning at large scales. Neotropical ecosystems have higher diversity and a different composition of frugivores and fleshy‐fruited plants compared with Afrotropical systems, but a lack of intercontinental comparisons lim...
Article
Indonesia is the largest producer of oil palm and the second largest exporter of rubber worldwide; a significant part of the country's rainforests have been converted to agriculture. Conservation measures are needed to assess and reduce the impact of agricultural intensification on the vertebrate fauna, but limited effort has been put so far in und...
Article
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To cope with biodiversity and climate change challenges, Education for Sustainable Development (ESD) needs to emphasize knowledge that considers multiple perspectives. Optimizing teacher education requires knowledge about the prerequisites of student teachers. The latter includes content knowledge with respect to Sustainable Development (SD). Apart...
Article
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Habitat fragmentation is a primary threat to biodiversity, but how it affects the structure and stability of ecological networks is poorly understood. Here, we studied plant–pollinator and host–parasitoid networks on 32 calcareous grassland fragments covering a size gradient of several orders of magnitude and with amounts of additional habitat avai...