John M. Holland
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Research Subjects
John M. Holland has a total of 345 co-authors. Here are the top co-authors by number of shared publications:
- Barbara Smith
Centre for Agroecology, Water and Resilience, Coventry University, Coventry, UK
14 shared publications - Dave Goulson
School of Life Sciences, University of Sussex, Brighton, UK
8 shared publications - Colin James Alexander
Biomathematics and Statistics Scotland, Invergowrie, Dundee, DD2 5DA, UK
7 shared publications - Niamh Mary McHugh
Farmland Ecology Unit, Game and Wildlife Conservation Trust, Fordingbridge, Hampshire, United Kingdom
7 shared publications - Eve Veromann
Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, Tartu, Estonia
6 shared publications Joe N. Perry
Plant and Invertebrate Ecology, Rothamsted Research, Harpenden, Herts, United Kingdom
6 shared publications
Latest Publications
- Open Access
- 6 April 2026
- Published by Wiley in Pest Management Science
- Vol. 82 (11) , 10658-10670
Community composition, abundance and activity‐density of carabids and staphylinids depend on prey abundance and adjacent habitat even in diverse agricultural landscapes
BACKGROUND: The functioning of agroecosystems depends on key ecosystem processes that deliver ecosystem services, yet agricultural management has increasingly shifted towards simplified landscapes lacking essential resources for service providers. Using field‐ and landscape‐scale approaches, we assessed how habitat composition and management shape predator communities and their pest control potential. This study assessed carabid and staphylinid communities in oilseed rape and field‐bordering habitats, relating predator abundance to prey availability, landscape metrics and field management. RESULTS: The type of field boundary habitat influenced carabid and staphylinid communities even in diverse landscapes. The activity‐density of both carabids and staphylinids in fields depended on field boundary habitat type, whereas their species communities in fields were a subset of the nearby habitats' communities. The high activity‐density and diversity were positively related to the sentinel prey consumption in winter oilseed rape fields. Furthermore, the abundance of superdominant species Poecilus cupreus increased with the abundance of its potential prey, the pollen beetle, and also was associated with a higher consumption of Calliphora sp. sentinel prey. Additionally, we provide a full species list of captured carabids and staphylinids. CONCLUSION: Local habitat characteristics, such as field‐boundary habitat type and prey availability, are key determinants of carabid and staphylinid assemblages – even in landscapes with high semi‐natural habitat coverage. Because crop field communities represent subsets of the species found in nearby semi‐natural habitats, these surrounding habitats play a pivotal role in sustaining biodiversity. This underscores the need for landscape‐level management approaches to ensure the provision of vital ecosystem services in agricultural systems. © 2026 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
- 6 April 2026
- Published by Wiley in Pest Management Science
- Vol. 82 (11) , 10658-10670
Open AccessCommunity composition, abundance and activity‐density of carabids and staphylinids depend on prey abundance and adjacent habitat even in diverse agricultural landscapes
BACKGROUND: The functioning of agroecosystems depends on key ecosystem processes that deliver ecosystem services, yet agricultural management has increasingly shifted towards simplified landscapes lacking essential resources for service providers. Using field‐ and landscape‐scale approaches, we assessed how habitat composition and management shape predator communities and their pest control potential. This study assessed carabid and staphylinid communities in oilseed rape and field‐bordering habitats, relating predator abundance to prey availability, landscape metrics and field management. RESULTS: The type of field boundary habitat influenced carabid and staphylinid communities even in diverse landscapes. The activity‐density of both carabids and staphylinids in fields depended on field boundary habitat type, whereas their species communities in fields were a subset of the nearby habitats' communities. The high activity‐density and diversity were positively related to the sentinel prey consumption in winter oilseed rape fields. Furthermore, the abundance of superdominant species Poecilus cupreus increased with the abundance of its potential prey, the pollen beetle, and also was associated with a higher consumption of Calliphora sp. sentinel prey. Additionally, we provide a full species list of captured carabids and staphylinids. CONCLUSION: Local habitat characteristics, such as field‐boundary habitat type and prey availability, are key determinants of carabid and staphylinid assemblages – even in landscapes with high semi‐natural habitat coverage. Because crop field communities represent subsets of the species found in nearby semi‐natural habitats, these surrounding habitats play a pivotal role in sustaining biodiversity. This underscores the need for landscape‐level management approaches to ensure the provision of vital ecosystem services in agricultural systems. © 2026 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
- Open Access
- 25 October 2024
- Published by IOP Publishing in Environmental Research: Food Systems
- Vol. 1 (2) , 025007
Measuring the transition to regenerative agriculture in the UK with a co-designed experiment: design, methods and expected outcomes
Regenerative agriculture is promoted as a farming system that can improve agricultural sustainability, address soil degradation, and provide ecosystem service benefits. However, there remains limited evidence for the quantifiable benefits of a widespread transition to regenerative agriculture on soil, biodiversity, and crop quality, particularly at the landscape scale, and poor integration of findings across disciplines. Social and cultural aspects of the transition, such as the positioning of regenerative agriculture as a grassroots movement, farmers’ perspectives on defining regenerative practices, and social or political barriers to implementation, are harder to quantify and often overlooked in evidence-based approaches. Here, we present the detailed methodology for our interdisciplinary, co-designed landscape-scale experiment measuring changes in soil health, biodiversity, yield, and grain quality, as well as social and political dimensions of the implementation of regenerative practices. Our unique approach, through the co-production process, the landscape-scale, and the focus on a systemic transition instead of individual practices, will bring strong evidence of the benefits of regenerative agriculture for sustained agricultural productivity, the mitigation of climate change and biodiversity depletion in agroecosystems. Our research aims to guide future studies transforming theoretical ecology into testable hypotheses in real-world systems and provide actionable evidence to inform agricultural policies in the UK and beyond.
- 25 October 2024
- Published by IOP Publishing in Environmental Research: Food Systems
- Vol. 1 (2) , 025007
Open AccessMeasuring the transition to regenerative agriculture in the UK with a co-designed experiment: design, methods and expected outcomes
Regenerative agriculture is promoted as a farming system that can improve agricultural sustainability, address soil degradation, and provide ecosystem service benefits. However, there remains limited evidence for the quantifiable benefits of a widespread transition to regenerative agriculture on soil, biodiversity, and crop quality, particularly at the landscape scale, and poor integration of findings across disciplines. Social and cultural aspects of the transition, such as the positioning of regenerative agriculture as a grassroots movement, farmers’ perspectives on defining regenerative practices, and social or political barriers to implementation, are harder to quantify and often overlooked in evidence-based approaches. Here, we present the detailed methodology for our interdisciplinary, co-designed landscape-scale experiment measuring changes in soil health, biodiversity, yield, and grain quality, as well as social and political dimensions of the implementation of regenerative practices. Our unique approach, through the co-production process, the landscape-scale, and the focus on a systemic transition instead of individual practices, will bring strong evidence of the benefits of regenerative agriculture for sustained agricultural productivity, the mitigation of climate change and biodiversity depletion in agroecosystems. Our research aims to guide future studies transforming theoretical ecology into testable hypotheses in real-world systems and provide actionable evidence to inform agricultural policies in the UK and beyond.
- Open Access
- 2 August 2024
- Published by Firenze University Press in Bio-based and Applied Economics
- Vol. 13 (4) , 397-417
Crop production, the pollinator deficit and land use management: UK farm level survey results
In this paper, we address a gap in the literature concerning pollination management, the pollinator deficit, and conservation objectives. By employing a farm level survey of UK farmers, we examine farmers’ attitudes, understanding and management of pollinators. Based on descriptive statistics and regression analysis, we found significant variation in interest and understanding of the impact of pollinators on commercial crops meaning that many respondents did not consider they had a pollinator deficit in terms of crop quality, quantity, or financial impacts. At the same time, many farmers are willing to adopt environmentally beneficial land-use measures if suitable advice and financial incentives are offered. However, there is little evidence of coordination of actions between farms to support wild pollinators. These findings indicate a potential disconnect between a farmer’s understanding of the impact on agricultural output from a pollinator deficit and the agricultural benefits from the adoption of specific environmental measures.
- 2 August 2024
- Published by Firenze University Press in Bio-based and Applied Economics
- Vol. 13 (4) , 397-417
Open AccessCrop production, the pollinator deficit and land use management: UK farm level survey results
In this paper, we address a gap in the literature concerning pollination management, the pollinator deficit, and conservation objectives. By employing a farm level survey of UK farmers, we examine farmers’ attitudes, understanding and management of pollinators. Based on descriptive statistics and regression analysis, we found significant variation in interest and understanding of the impact of pollinators on commercial crops meaning that many respondents did not consider they had a pollinator deficit in terms of crop quality, quantity, or financial impacts. At the same time, many farmers are willing to adopt environmentally beneficial land-use measures if suitable advice and financial incentives are offered. However, there is little evidence of coordination of actions between farms to support wild pollinators. These findings indicate a potential disconnect between a farmer’s understanding of the impact on agricultural output from a pollinator deficit and the agricultural benefits from the adoption of specific environmental measures.
- Open Access
- 17 December 2023
- Published by Journal of Pollination Ecology (ASBL) in Journal of Pollination Ecology
- Vol. 34, 341-357
Crop and landscape factors affecting variation in composition and behaviour of the pollinator community in field bean crops
The global decline in pollinators is likely to negatively affect the yield of insect pollinated crops such as field beans (Vicia faba). To understand the impact of such declines it is important to investigate how the abundance, composition and behaviour of the pollinator community relates to crop yield. We observed pollinators (specifically Bombus spp. and Apis mellifera) foraging in field bean fields. Some bees actively pollinated flowers whereas others robbed the nectar without actively pollinating the flowers. As legitimate foraging visits are more likely to pollinate the crop, we explored infield and landscape scale factors affecting this variation in behaviour. Infield factors included sowing time (winter/spring) and plant density. Landscape factors were the area of flower-rich habitat, and of mass-flowering crops within 1 km of the bean field. We also explored how the abundance and behaviour of different functional groups (short-tongued bumblebees, long-tongued bumblebees or honeybees) responded to these factors. Finally, we assessed how the abundance and behaviour of these pollinators affected field bean yield. Pollinators were more abundant in bean crops that were spring sown and where there was a smaller area of mass-flowering crops in the landscape. Functional groups varied in their predominant foraging behaviour and in how their behaviour was influenced by external factors. There was no relationship between pollinator abundance and bean yield however the proportion of pollinators legitimately foraging was negatively related to yield. Our findings align with previous research in suggesting that the benefits of insect pollinators for field beans are context specific. Additional work is required to develop pollinator conservation measures that will facilitate crop pollination.
- 17 December 2023
- Published by Journal of Pollination Ecology (ASBL) in Journal of Pollination Ecology
- Vol. 34, 341-357
Open AccessCrop and landscape factors affecting variation in composition and behaviour of the pollinator community in field bean crops
The global decline in pollinators is likely to negatively affect the yield of insect pollinated crops such as field beans (Vicia faba). To understand the impact of such declines it is important to investigate how the abundance, composition and behaviour of the pollinator community relates to crop yield. We observed pollinators (specifically Bombus spp. and Apis mellifera) foraging in field bean fields. Some bees actively pollinated flowers whereas others robbed the nectar without actively pollinating the flowers. As legitimate foraging visits are more likely to pollinate the crop, we explored infield and landscape scale factors affecting this variation in behaviour. Infield factors included sowing time (winter/spring) and plant density. Landscape factors were the area of flower-rich habitat, and of mass-flowering crops within 1 km of the bean field. We also explored how the abundance and behaviour of different functional groups (short-tongued bumblebees, long-tongued bumblebees or honeybees) responded to these factors. Finally, we assessed how the abundance and behaviour of these pollinators affected field bean yield. Pollinators were more abundant in bean crops that were spring sown and where there was a smaller area of mass-flowering crops in the landscape. Functional groups varied in their predominant foraging behaviour and in how their behaviour was influenced by external factors. There was no relationship between pollinator abundance and bean yield however the proportion of pollinators legitimately foraging was negatively related to yield. Our findings align with previous research in suggesting that the benefits of insect pollinators for field beans are context specific. Additional work is required to develop pollinator conservation measures that will facilitate crop pollination.
- Open Access
- 10 July 2023
- Published by Wiley in Journal of Applied Ecology
- Vol. 60 (9) , 2040-2051
Resolving a heated debate: The utility of prescribed burning as a management tool for biodiversity on lowland heath
Lowland heath is a priority habitat for conservation, nowadays largely managed for biodiversity. Historically, prescribed burning has been the principal management tool, but there are increasing calls to substitute burning with cutting to improve biodiversity outcomes. However, poor understanding of potential impacts compromises decision making. Our study was carried out in the New Forest National Park, the largest area of lowland heath in Europe. Using a multi‐trophic approach, we compared the ecological impact of prescribed burning with two types of vegetation cutting (swiping and baling) as management tools for biodiversity outcomes for up to 20 years after management. Indicators included: common standards monitoring (CSM) assessment; vegetation species assemblage; below‐ and above‐ground invertebrate biodiversity; and available food resources for two characteristic heathland birds—the Dartford Warbler Sylvia undata and the Nightjar Caprimulgus europaeus. When compared with swiped sites, areas managed by prescribed burning resulted in: better habitat condition (assessed by CSM); higher cover of heathers; lower bracken cover; more areas of bare ground. We found no evidence that burning is detrimental for the investigated components of biodiversity. Cutting by swiping did not replicate the benefits of burning. Swiping supported grassland conditions that suit non‐heathland species. Baling resulted in habitat condition similar to prescribed burning but restricted replication of baled sites limited our conclusions. However, swiped sites supported high invertebrate abundance and diversity, including food resources for Dartford Warbler and Nightjar. Synthesis and applications. Removing burning from the management programme is likely to reduce heathland condition. Biodiversity is encouraged by a mosaic of management and more mobile species, such as birds, will exploit the resources provided by several management techniques. Including some cutting in a rotational regime is likely to be beneficial although prescribed burning should form the majority of the management programme, Lowland heathland differs fundamentally from upland heathland/moorland and it is not easy to transfer the results. Current heathland CSM does not adequately assess wider biodiversity on protected areas but is effectively an assessment of vegetation feature condition. Including invertebrates in surveys provides a more nuanced assessment of heathland condition.
- 10 July 2023
- Published by Wiley in Journal of Applied Ecology
- Vol. 60 (9) , 2040-2051
Open AccessResolving a heated debate: The utility of prescribed burning as a management tool for biodiversity on lowland heath
Lowland heath is a priority habitat for conservation, nowadays largely managed for biodiversity. Historically, prescribed burning has been the principal management tool, but there are increasing calls to substitute burning with cutting to improve biodiversity outcomes. However, poor understanding of potential impacts compromises decision making. Our study was carried out in the New Forest National Park, the largest area of lowland heath in Europe. Using a multi‐trophic approach, we compared the ecological impact of prescribed burning with two types of vegetation cutting (swiping and baling) as management tools for biodiversity outcomes for up to 20 years after management. Indicators included: common standards monitoring (CSM) assessment; vegetation species assemblage; below‐ and above‐ground invertebrate biodiversity; and available food resources for two characteristic heathland birds—the Dartford Warbler Sylvia undata and the Nightjar Caprimulgus europaeus. When compared with swiped sites, areas managed by prescribed burning resulted in: better habitat condition (assessed by CSM); higher cover of heathers; lower bracken cover; more areas of bare ground. We found no evidence that burning is detrimental for the investigated components of biodiversity. Cutting by swiping did not replicate the benefits of burning. Swiping supported grassland conditions that suit non‐heathland species. Baling resulted in habitat condition similar to prescribed burning but restricted replication of baled sites limited our conclusions. However, swiped sites supported high invertebrate abundance and diversity, including food resources for Dartford Warbler and Nightjar. Synthesis and applications. Removing burning from the management programme is likely to reduce heathland condition. Biodiversity is encouraged by a mosaic of management and more mobile species, such as birds, will exploit the resources provided by several management techniques. Including some cutting in a rotational regime is likely to be beneficial although prescribed burning should form the majority of the management programme, Lowland heathland differs fundamentally from upland heathland/moorland and it is not easy to transfer the results. Current heathland CSM does not adequately assess wider biodiversity on protected areas but is effectively an assessment of vegetation feature condition. Including invertebrates in surveys provides a more nuanced assessment of heathland condition.
- 27 April 2021
- Published by Wiley in Pest Management Science
- Vol. 77 (9) , 4100-4108
Field specific monitoring of cereal yellow dwarf virus aphid vectors and factors influencing their immigration within fields
BACKGROUND: Neonicotinoid insecticide seed treatments were withdrawn from use on cereal crops in the European Union (EU) in 2018 exposing the crops to yellow dwarf viruses transmitted by cereal aphids. To reduce prophylactic pyrethroid sprays there is a need for easier, field‐specific monitoring techniques given that pest incidence is spatially and temporally highly sporadic.A field‐specific monitoring method based on the use of yellow sticky traps mounted horizontally just above the crop was developed and evaluated to determine: (i) predictive capabilities of the sticky trap system, (ii) practicalities of use by farmers and agronomists, and (iii) whether landscape composition, boundary type and type of tillage affect immigration of aphid vectors.RESULTS: Yellow sticky traps effectively sampled winged cereal aphids and identified spatial differences in immigration patterns within‐ and between fields. Farmers and agronomist's aphid identification skills need improving, although they could detect aphid trends with minimal training. At least three times more cereal aphids were captured in crop headlands, especially next to taller field boundaries indicating that wind currents determined aphid immigration patterns within fields. Considerable between field aphid immigration was detected (24% of fields had no aphid immigration) even on the same farm. Levels of immigrating grain aphids were positively related to the proportion of grassland in the landscape. Tillage type had no impact on levels of immigrating aphids.CONCLUSION: Field‐based monitoring and different management of headland areas could be used to reduce insecticide usage when controlling of cereal/barley yellow dwarf virus.
- 27 April 2021
- Published by Wiley in Pest Management Science
- Vol. 77 (9) , 4100-4108
Field specific monitoring of cereal yellow dwarf virus aphid vectors and factors influencing their immigration within fields
BACKGROUND: Neonicotinoid insecticide seed treatments were withdrawn from use on cereal crops in the European Union (EU) in 2018 exposing the crops to yellow dwarf viruses transmitted by cereal aphids. To reduce prophylactic pyrethroid sprays there is a need for easier, field‐specific monitoring techniques given that pest incidence is spatially and temporally highly sporadic.A field‐specific monitoring method based on the use of yellow sticky traps mounted horizontally just above the crop was developed and evaluated to determine: (i) predictive capabilities of the sticky trap system, (ii) practicalities of use by farmers and agronomists, and (iii) whether landscape composition, boundary type and type of tillage affect immigration of aphid vectors.RESULTS: Yellow sticky traps effectively sampled winged cereal aphids and identified spatial differences in immigration patterns within‐ and between fields. Farmers and agronomist's aphid identification skills need improving, although they could detect aphid trends with minimal training. At least three times more cereal aphids were captured in crop headlands, especially next to taller field boundaries indicating that wind currents determined aphid immigration patterns within fields. Considerable between field aphid immigration was detected (24% of fields had no aphid immigration) even on the same farm. Levels of immigrating grain aphids were positively related to the proportion of grassland in the landscape. Tillage type had no impact on levels of immigrating aphids.CONCLUSION: Field‐based monitoring and different management of headland areas could be used to reduce insecticide usage when controlling of cereal/barley yellow dwarf virus.
- 1 October 2020
- Published by Elsevier in Agriculture, Ecosystems & Environment
- Vol. 302
Moderate pollination limitation in some entomophilous crops of Europe
- 1 October 2020
- Published by Elsevier in Agriculture, Ecosystems & Environment
- Vol. 302
Moderate pollination limitation in some entomophilous crops of Europe
- Open Access
Erratum: Holland, J.M., et al. Approaches to Identify the Value of Seminatural Habitats for Conservation Biological Control. Insects 2020, 11, 195
We would like to make the following correction to the published paper
Open AccessErratum: Holland, J.M., et al. Approaches to Identify the Value of Seminatural Habitats for Conservation Biological Control. Insects 2020, 11, 195
We would like to make the following correction to the published paper
- Open Access
Approaches to Identify the Value of Seminatural Habitats for Conservation Biological Control
Invertebrates perform many vital functions in agricultural production, but many taxa are in decline, including pest natural enemies. Action is needed to increase their abundance if more sustainable agricultural systems are to be achieved. Conservation biological control (CBC) is a key component of integrated pest management yet has failed to be widely adopted in mainstream agriculture. Approaches to improving conservation biological control have been largely ad hoc. Two approaches are described to improve this process, one based upon pest natural enemy ecology and resource provision while the other focusses on the ecosystem service delivery using the QuESSA (Quantification of Ecological Services for Sustainable Agriculture) project as an example. In this project, a predictive scoring system was developed to show the potential of five seminatural habitat categories to provide biological control, from which predictive maps were generated for Europe. Actual biological control was measured in a series of case studies using sentinel systems (insect or seed prey), trade-offs between ecosystem services were explored, and heatmaps of biological control were generated. The overall conclusion from the QuESSA project was that results were context specific, indicating that more targeted approaches to CBC are needed. This may include designing new habitats or modifying existing habitats to support the types of natural enemies required for specific crops or pests.
Open AccessApproaches to Identify the Value of Seminatural Habitats for Conservation Biological Control
Invertebrates perform many vital functions in agricultural production, but many taxa are in decline, including pest natural enemies. Action is needed to increase their abundance if more sustainable agricultural systems are to be achieved. Conservation biological control (CBC) is a key component of integrated pest management yet has failed to be widely adopted in mainstream agriculture. Approaches to improving conservation biological control have been largely ad hoc. Two approaches are described to improve this process, one based upon pest natural enemy ecology and resource provision while the other focusses on the ecosystem service delivery using the QuESSA (Quantification of Ecological Services for Sustainable Agriculture) project as an example. In this project, a predictive scoring system was developed to show the potential of five seminatural habitat categories to provide biological control, from which predictive maps were generated for Europe. Actual biological control was measured in a series of case studies using sentinel systems (insect or seed prey), trade-offs between ecosystem services were explored, and heatmaps of biological control were generated. The overall conclusion from the QuESSA project was that results were context specific, indicating that more targeted approaches to CBC are needed. This may include designing new habitats or modifying existing habitats to support the types of natural enemies required for specific crops or pests.
- Open Access
- 10 January 2020
- Published by Frontiers Media SA in Frontiers in Sustainable Food Systems
- Vol. 3
The Potential of Arable Weeds to Reverse Invertebrate Declines and Associated Ecosystem Services in Cereal Crops
There is global concern that invertebrate populations are declining rapidly, particularly in agricultural habitats. Declines have been attributed to the intensification of farming systems, with many studies focussing on a lack of semi-natural habitat in the landscape and the use of insecticides. However, within-field arable weeds are also an important driver of invertebrate abundance and the ecosystem services to which they contribute. This study focuses on the role of arable weeds in supporting invertebrate populations and selected ecosystem services they deliver., using winter wheat as a case study. Weed-invertebrate relationships were investigated across seven studies of winter-sown wheat spanning 18 years. Both phytophagous and predatory invertebrates responded to weed cover but to different degrees. Phytophages showed a stronger positive relationship with weed cover than the predators, because they rely on the resources provided by the weeds whereas predatory species response is likely to be mediated by their prey. Farmland bird chick-food indices were positively related to both broadleaf and grass cover in cropped fields, indicating that increased weed cover can provide increased invertebrate food for birds in winter wheat. Despite this potential, there were insufficient invertebrate food resources for birds in the majority of wheat fields sampled. Weed diversity did not play a significant role in moderating the relationships between weeds and invertebrate abundance, however this may be a function of the low weed diversity in modern winter wheat fields. In this study the weed species most frequently shown to predict the invertebrate community were: Poa annua, Stellaria media, Fumaria officinalis, Sinapis arvensis, Senecio vulgaris, Persicaria lapathifolia, Sonchus spp., Matricaria discoidea, Persicaria maculosa, Agrostis spp., Lamium purpureum, Lamium album, Veronica spp., Atriplex spp., Myosotis spp. and Anagallis arvensis. We conclude that even in an intensively grown cereal, arable weeds can play an important role in maintaining and restoring invertebrate populations, that 10% weed cover is needed to fulfill the potential and that a successful outcome will be driven by the presence of weed species that support invertebrates that provide ecosystem services.
- 10 January 2020
- Published by Frontiers Media SA in Frontiers in Sustainable Food Systems
- Vol. 3
Open AccessThe Potential of Arable Weeds to Reverse Invertebrate Declines and Associated Ecosystem Services in Cereal Crops
There is global concern that invertebrate populations are declining rapidly, particularly in agricultural habitats. Declines have been attributed to the intensification of farming systems, with many studies focussing on a lack of semi-natural habitat in the landscape and the use of insecticides. However, within-field arable weeds are also an important driver of invertebrate abundance and the ecosystem services to which they contribute. This study focuses on the role of arable weeds in supporting invertebrate populations and selected ecosystem services they deliver., using winter wheat as a case study. Weed-invertebrate relationships were investigated across seven studies of winter-sown wheat spanning 18 years. Both phytophagous and predatory invertebrates responded to weed cover but to different degrees. Phytophages showed a stronger positive relationship with weed cover than the predators, because they rely on the resources provided by the weeds whereas predatory species response is likely to be mediated by their prey. Farmland bird chick-food indices were positively related to both broadleaf and grass cover in cropped fields, indicating that increased weed cover can provide increased invertebrate food for birds in winter wheat. Despite this potential, there were insufficient invertebrate food resources for birds in the majority of wheat fields sampled. Weed diversity did not play a significant role in moderating the relationships between weeds and invertebrate abundance, however this may be a function of the low weed diversity in modern winter wheat fields. In this study the weed species most frequently shown to predict the invertebrate community were: Poa annua, Stellaria media, Fumaria officinalis, Sinapis arvensis, Senecio vulgaris, Persicaria lapathifolia, Sonchus spp., Matricaria discoidea, Persicaria maculosa, Agrostis spp., Lamium purpureum, Lamium album, Veronica spp., Atriplex spp., Myosotis spp. and Anagallis arvensis. We conclude that even in an intensively grown cereal, arable weeds can play an important role in maintaining and restoring invertebrate populations, that 10% weed cover is needed to fulfill the potential and that a successful outcome will be driven by the presence of weed species that support invertebrates that provide ecosystem services.