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A modelling approach to evaluate the effectiveness of different mitigation strategies to reduce the negative effects of agricultural practices on biodiversity in the Netherlands: Final report within the framework of the project: "Developing and application of a methodology to assess impacts of pesticides on key ecosystem services"
Abstract and Figures
A report of simulations conducted with ALMaSS, a simulation systems for evaluating the impact of management on wildlife, for different pesticide management strategies in 10 landscapes in The Netherlands, and for a carabid beetle, skylarks and hares.
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... Calculations with the ALMaSS model (Ziółkowska and Topping, 2019) show that driftreducing measures have little effect on the occurrence of the Bembidion lampros beetle. This ground beetle plays an important role in natural pest control and is comparable to other ground beetles in terms of behaviour. ...
... In addition to reducing environmental impact, the creation of field margins is an effective measure to stimulate functional agricultural biodiversity ( Figure 30; Ziółkowska and Topping, 2019;EFSA PPR Panel, 2015). The effect is the strongest in areas that currently contain few landscape elements. ...
... The Animal, Landscape and Man Simulation System (ALMaSS) (Topping et al., 2003) used in this study has been already applied to evaluate the impact of changing insecticide toxicity and landscape structure on population density and the distribution of beetles in exemplary landscapes in Denmark (Topping et al., 2015 and in the Netherlands (Ziółkowska and Topping, 2019). However, findings obtained in these two countries may not be fully applicable across Europe, as each country is probably unique in its combination of landscape structure and management. ...
Intensification of agricultural practices is one of the most important drivers of the dramatic decline of arthropod species. We do not know, however, the relative contribution to decline of different anthropogenic stressors that are part of this process. We used high-resolution dynamic landscape models and advanced spatially-explicit population modelling to estimate the relative importance of insecticide use and landscape structure for population dynamics of a widespread carabid beetle Bembidion lampros. The effects of in-crop mitigation measures through the application of insecticides with reduced lethality, and off-crop mitigation measures by increasing abundance of grassy field margins, were evaluated for the beetle along the gradient of landscape heterogeneity. Reducing the insecticide-driven lethality (from 90 to 10%) had larger positive impacts on beetle density and occupancy than increasing the abundance of field margins in a landscape. The effects of increasing field margins depended on their width and overall abundance in the landscape, but only field margins 4 m wide, applied to at least 40% of fields, resulted in an increase in beetle population density comparable to the scenario with the smallest reduction of insecticide-driven lethality we considered. Our findings suggest the importance of field margins rather as a supporting not stand-alone mitigation measure, as they generally improved effects of reduction of insecticide-driven lethality. Therefore, adding sufficiently broad off-field habitats should help to maintain viable beetle populations in agricultural landscapes even with moderate use of insecticides. In general, the less persistent the insecticides are in the environment, the larger positive impacts of applied mitigation measures on beetle populations were found. We also showed that the effectiveness of applied mitigation measures strongly depends on landscape and farmland heterogeneity. Thus, to achieve the same management or mitigation target in different landscapes might require different strategies.
Recently, reports of insect declines prompted concerns with respect to the state of insects at a global level. Here we
present the results of long-term insect monitoring from two locations, De Kaaistoep, and nature reserves in Drenthe,
both in the Netherlands. We report the trends in beetles (Coleoptera), macro-moths (macro-Lepidoptera), caddis
ies
(Trichoptera), lacewings (Neuroptera), may
ies (Ephemeroptera) and true bugs (Hemiptera), using light traps, and
ground beetles (Coleoptera: Carabidae), using pitfall traps. Based on data from light traps, macro-moths, ground
beetles, and caddis
ies have declined in the mean number of individuals counted per evening, with annual rates of
decline of 3.8, 5.0 and 9.2% respectively. Other orders appeared stable (true bugs) or had great uncertainty in the
trend estimate (lacewings and may
ies). Based on data from pitfall traps, ground beetles showed a mean annual
decline of 4.3% in total annual numbers over the period 1985-2016. However declines appeared stronger after 1995
or when only including traps that were operated for longer periods. Annual trends in total numbers of macro-
moths were comparable (but less) to the average of the individual species annual trends. Contrary, annual trends
in total numbers of ground beetles were more severe than the average of the individual species trend, suggesting
that abundant species may fare worse than rare ones. Our results suggest a reduction in biomass in macro-moths of
approximately 61% and in ground beetles of at least 42%, over a period of 27 years. Estimated weights of ground
beetles and macro-moths were not signi�cantly related to individual species trends, suggesting that heavy species did
not contribute disproportionately to the biomass decline. Our results broadly echo recent reported trends in insect
biomass in Germany, even though the comparison is only partly possible.
Agricultural intensification is one of the main causes for the current biodiversity crisis. While reversing habitat loss on agricultural land is challenging, increasing the farmland configurational heterogeneity (higher field border density) and farmland compositional heterogeneity (higher crop diversity) has been proposed to counteract some habitat loss. Here, we tested whether increased farmland configurational and compositional heterogeneity promote wild pollinators and plant reproduction in 229 landscapes located in four major western European agricultural regions. High-field border density consistently increased wild bee abundance and seed set of radish (Raphanus sativus), probably through enhanced connectivity. In particular, we demonstrate the importance of crop-crop borders for pollinator movement as an additional experiment showed higher transfer of a pollen analogue along crop-crop borders than across fields or along semi-natural crop borders. By contrast, high crop diversity reduced bee abundance, probably due to an increase of crop types with particularly intensive management. This highlights the importance of crop identity when higher crop diversity is promoted. Our results show that small-scale agricultural systems can boost pollinators and plant reproduction. Agri-environmental policies should therefore aim to halt and reverse the current trend of increasing field sizes and to reduce the amount of crop types with particularly intensive management.
Large-scale use of the persistent and potent neonicotinoid and fipronil insecticides has raised concerns about risks to ecosystem functions provided by a wide range of species and environments affected by these insecticides. The concept of ecosystem services is widely used in decision making in the context of valuing the service potentials, benefits, and use values that well-functioning ecosystems provide to humans and the biosphere and, as an endpoint (value to be protected), in ecological risk assessment of chemicals. Neonicotinoid insecticides are frequently detected in soil and water and are also found in air, as dust particles during sowing of crops and aerosols during spraying. These environmental media provide essential resources to support biodiversity, but are known to be threatened by long-term or repeated contamination by neonicotinoids and fipronil. We review the state of knowledge regarding the potential impacts of these insecticides on ecosystem functioning and services provided by terrestrial and aquatic ecosystems including soil and freshwater functions, fisheries, biological pest control, and pollination services. Empirical studies examining the specific impacts of neonicotinoids and fipronil to ecosystem services have focused largely on the negative impacts to beneficial insect species (honeybees) and the impact on pollination service of food crops. However, here we document broader evidence of the effects on ecosystem functions regulating soil and water quality, pest control, pollination, ecosystem resilience, and community diversity. In particular, microbes, invertebrates, and fish play critical roles as decomposers, pollinators, consumers, and predators, which collectively maintain healthy communities and ecosystem integrity. Several examples in this review demonstrate evidence of the negative impacts of systemic insecticides on decomposition, nutrient cycling, soil respiration, and invertebrate populations valued by humans. Invertebrates, particularly earthworms that are important for soil processes, wild and domestic insect pollinators which are important for plant and crop production, and several freshwater taxa which are involved in aquatic nutrient cycling, were all found to be highly susceptible to lethal and sublethal effects of neonicotinoids and/or fipronil at environmentally relevant concentrations. By contrast, most microbes and fish do not appear to be as sensitive under normal exposure scenarios, though the effects on fish may be important in certain realms such as combined fish-rice farming systems and through food chain effects. We highlight the economic and cultural concerns around agriculture and aquaculture production and the role these insecticides may have in threatening food security. Overall, we recommend improved sustainable agricultural practices that restrict systemic insecticide use to maintain and support several ecosystem services that humans fundamentally depend on.
Spatio-temporal landscape heterogeneity has rarely been considered in population-level impact assessments. Here we test whether landscape heterogeneity is important by examining the case of a pesticide applied seasonally to orchards which may affect non-target vole populations, using a validated ecologically realistic and spatially explicit agent-based model. Voles thrive in unmanaged grasslands and untreated orchards but are particularly exposed to applied pesticide treatments during dispersal between optimal habitats. We therefore hypothesised that vole populations do better (1) in landscapes containing more grassland and (2) where areas of grassland are closer to orchards, but (3) do worse if larger areas of orchards are treated with pesticide. To test these hyposeses we made appropriate manipulations to a model landscape occupied by field voles. Pesticide application reduced model population sizes in all three experiments, but populations subsequently wholly or partly recovered. Population depressions were, as predicted, lower in landscapes containing more unmanaged grassland, in landscapes with reduced distance between grassland and orchards, and in landscapes with fewer treated orchards. Population recovery followed a similar pattern except for an unexpected improvement in recovery when the area of treated orchards was increased. Outside the period of pesticide application, orchards increase landscape connectivity and facilitate vole dispersal and so speed population recovery. Overall our results show that accurate prediction of population impact cannot be achieved without taking account of landscape structure. The specifics of landscape structure and habitat connectivity are likely always important in mediating the effects of stressors.
Ground beetles (Coleoptera, Carabidae) occur in all temperate agroecosystems, and have been implicated as predators of many pests, including aphids, lepidopterous larvae, and slugs. Most are polyphagous, and some are primarily spermophagous. The species assemblage present in any particular crop is determined by multiple factors, but usually comprises a limited number of abundantly active species, which may be common to many crop types. Abiotic soil factors, especially soil type and moisture status are important in determining the species present. Crop type affects the carabid assemblage indirectly through cultivation practices and microclimatic changes. Any soil cultivation affects the carabid assemblage, but studies comparing ploughing with reduced tillage have shown varying results, according to local conditions. Pesticides, especially insecticides have a localised and short-term effect, as many carabids rapidly re-invade sprayed crops. The long-term effect of pesticide usage at a landscape scale is, however, more difficult to predict, and may have contributed to the observed decline in carabid diversity in the wider countryside. Whilst fertiliser application is generally beneficial to carabids, comparisons of conventional and organic farming systems suggest that localised short-term variations in species’ abundances are more important than the overall farming system used. Non-crop habitats are very important to Carabidae, as many use adjacent hedges and field margins for shelter, breeding or dispersal. But other features such as roads may act as barriers to dispersal. It is concluded that further measures need to be taken if Carabidae are to realise their potential in integrated pest management systems.
Agricultural intensification poses a serious threat to biodiversity as a consequence of increased land-use intensity, decreased landscape heterogeneity and reduced habitat diversity. Although there is interest in the preservation of total species richness of an agricultural landscape (gamma diversity), the effects of intensification have been assessed primarily by species richness at a local scale (alpha diversity). This ignores species richness between local communities (beta diversity), which is an important component of total species richness.
In this study, measures of land-use intensity, landscape structure and habitat diversity were related to gamma, alpha and beta diversity of wild bees (Apoidea), carabid beetles (Carabidae), hoverflies (Syrphidae), true bugs (Heteroptera) and spiders (Araneae) within 16 local communities in 24 temperate European agricultural landscapes.
The total landscape species richness of all groups was most strongly affected by increased proximity of semi-natural habitat patches. Bees also decreased in landscapes with a high intensity of farmland management, demonstrating additive effects of both factors.
Separating total species diversity into components, the decrease in total species richness could be attributed primarily to a decrease in species diversity between local communities. Species richness of the local communities of all investigated groups decreased with increasing land-use intensity and, in the case of spiders, decreasing proximity of the semi-natural habitat patches.
The effect of increased habitat diversity appeared to be of secondary importance to total species richness but caused a shift in the relative contribution of alpha and beta diversity towards the latter.
Synthesis and applications. This study demonstrates that the effects of agricultural change operate at a landscape level and that examining species diversity at a local level fails to explain the total species richness of an agricultural landscape. The coincidence of patterns of beta diversity with those of gamma diversity emphasizes that such information is of crucial importance for the implementation and evaluation of restoration programmes aiming to restore sustainable countryside diversity. As local extinction processes in highly fragmented landscapes shape biodiversity, priority should be given to the conservation of diverse agricultural landscape remnants in Europe.
1. In many European agricultural landscapes, species richness is declining considerably. Studies performed at a very large spatial scale are helpful in understanding the reasons for this decline and as a basis for guiding policy. In a unique, large-scale study of 25 agricultural landscapes in seven European countries, we investigated relationships between species richness in several taxa, and the links between biodiversity and landscape structure and management. 2. We estimated the total species richness of vascular plants, birds and five arthropod groups in each 16-km2 landscape, and recorded various measures of both landscape structure and intensity of agricultural land use. We studied correlations between taxonomic groups and the effects of landscape and land-use parameters on the number of species in different taxonomic groups. Our statistical approach also accounted for regional variation in species richness unrelated to landscape or land-use factors. 3. The results reveal strong geographical trends in species richness in all taxonomic groups. No single species group emerged as a good predictor of all other species groups. Species richness of all groups increased with the area of semi-natural habitats in the landscape. Species richness of birds and vascular plants was negatively associated with fertilizer use. 4. Synthesis and applications. We conclude that indicator taxa are unlikely to provide an effective means of predicting biodiversity at a large spatial scale, especially where there is large biogeographical variation in species richness. However, a small list of landscape and land-use parameters can be used in agricultural landscapes to infer large-scale patterns of species richness. Our results suggest that to halt the loss of biodiversity in these landscapes, it is important to preserve and, if possible, increase the area of semi-natural habitat.
Population persistence of animals that have specific habitat requirements in certain life history stages is influenced by spatial and temporal availability of the required habitat. Accessibility of suitable habitats may be affected by their spatial distribution in the landscape and by dispersal ability of the animals. Animals with low dispersal power should be more vulnerable to spatial variation in the distribution of suitable habitats than animals with high dispersal ability. We investigated the effects of differential dispersal power and landscape composition on population dynamics of a terrestrial arthropod by use of a spatially explicit individual-based simulation model. The model was parameterized with data from a common spring breeding carabid beetle in European agroecosystems. Spring-breeding ground beetles depend largely on vegetated field boundaries for (winter) hibernation. We analyzed the effects of and interaction between dispersal rate, field size, and availability of hibernation sites on beetle population development and spatial dynamics. A landscape composed of small fields and a high boundary-to-field size ratio supported larger beetle populations than a landscape consisting of large fields. Animal populations were more robust to variation in spatial distribution of required habitat when dispersal power of individuals was high. In a landscape of large fields, beetles were found to associate with the field boundaries, whereas such an association was not observed in a landscape composed of small fields, suggesting that distance to hibernation sites may be a limiting factor for habitat use. Interactions between life history traits and essential habitat requirements may have profound effects on population dynamics and play an important role in predictions of effects of landscape changes on animal populations.
This review article on carabids in sustainable agro-ecosystems of the temperate Northern hemisphere presents a compilation of the available knowledge on the significance of carabids for natural pest control and the effects of cultivation methods (except pesticides) and landscape structural elements.Field carabids are species rich and abundant in arable sites, but are affected by intensive agricultural cultivation. For sampling, fenced pitfall trapping or pitfall trapping is recommended according to the type of study.Many of the assumed beneficial pest control activities of carabids are still based on laboratory feeding records. In the field, carabids have been demonstrated to reduce cereal and sugar beet aphid populations in their early colonization phase, mainly by foraging on aphids that have fallen from the vegetation. Egg predation on Dipteran eggs, e.g. the cabbage root fly, has been overestimated in earlier literature. Scattered data indicate carabidforaging on certain coleopteran pest larvae. In North America, some evidence has been found for control of pest lepidopterans. Larger carabids, e.g. Abax parallelepipedus, can effectively control slugs in greenhouses. Because of their spermophagous feeding habits, certain species of Harpalus and Amara could have some potential for biological weed control.As a result of their sensitive reaction to anthropogenic changes in habitat quality, carabids are considered of bioindicative value for cultivation impacts. Carabids seem to be negatively affected by deep ploughing and enhanced by reduced tillage systems. No negative effects have been found for mechanical weed control and flaming. Carabid recruitment is enhanced by proper organic fertilization and green manuring. Intensive nitrogen amendment might indirectly affect carabids by altering crop density and microclimate.Field carabid assemblages are not bound to a certain crop type, but shift in dominance according to the crop-specific rhythmicity of cultivation measures and changes in crop phenology and microclimate. Crop rotation effects could also be influenced by field-size dependent recolonization capability of carabids. They are enhanced by crop diversification in terms of monocrop heterogeneity and weediness as well as by intercropping and the presence of field boundaries, although corresponding increases in their pest reduction efficacy have not yet been evidenced.