Working Papers are interim reports on work of Mansholt Graduate School (MG3S) and have received o... more Working Papers are interim reports on work of Mansholt Graduate School (MG3S) and have received only limited reviews 1. Each paper is refereed by one member of the Editorial Board and one member outside the board. Views or opinions expressed in them do not necessarily represent those of the Mansholt Graduate School. The Mansholt Graduate School's researchers are based in two departments: 'Social Sciences' and 'Environmental Sciences' and two institutes: 'LEI, Agricultural Economics Research Institute' and 'Alterra, Research Institute for the Green World'. In total Mansholt Graduate School comprises about 250 researchers. Mansholt Graduate School is specialised in social scientific analyses of the rural areas and the agri-and food chains. The Graduate School is known for its disciplinary and interdisciplinary work on theoretical and empirical issues concerning the transformation of agriculture, rural areas and chains towards multifunctionality and sustainability. Comments on the Working Papers are welcome and should be addressed directly to the author(s).
Human activities such as land use and-management may strongly affect the soil's ability to provid... more Human activities such as land use and-management may strongly affect the soil's ability to provide ecosystem services, in which microbes are playing a key role. Because sampling is usually restricted to the topsoil, little is known about effects of land use on ecosystem functioning down the soil profile. The present study assessed the effects of different land use types (arable, forest, grassland) on soil microbial biomass, activity and community structure at different soil depths (A, AC, C horizons), under the same climatic and pedological conditions, in the Danube Floodplain in Austria. Microbial biomass was 4e5 times lower in the arable field than in forest and grassland in the upper horizons. Additionally, both microbial biomass and activity decreased 3e4 fold with soil depth in forest and grassland. However, up to 30% of total microbial biomass was found in the C horizon in the arable field. We found a differentiation of microbial community structure between land use types and with soil depth: i.e. strong differences in the topsoil between land uses, whereas community structure in the C horizon was similar. This study confirms that land use exerts strong effects on soil microbes in the topsoil and that microbial biomass and activity decrease with soil depth. However, considerable microbial biomass and activity are found below 30 cm depth which is usually not included in samplings. In the deeper soil horizon effects of land use disappear, with microbial community structure and functioning becoming similar in similar pedological conditions.
A stochastic model is formulated to determine the optimal strategy for a solitary parasitoid whic... more A stochastic model is formulated to determine the optimal strategy for a solitary parasitoid which has discovered an already parasitized host. The model assumes that the parasitoid can count both the number of eggs already present in a host and the number of conspecifics searching in the same patch. The survival probability of an egg is assumed to depend on the total number of eggs in a host. The decision to (super)parasitize depends both on the degree to which the discovered host already is parasitized and on the number of conspecific females searching in the same patch. We consider both the case that egg laying does not involve any costs for the parasitoid and the case that it involves some marginal costs. Uniform behaviour of all the conspecific parasitoids in a patch, i.e. laying one additional egg in all encountered larvae containing a particular number of eggs, appears to be a pure evolutionary stable strategy (ESS). If either the probability that a parasitoid emerges from a host decreases with an increasing degree of parasitism, at least from a particular number of eggs onwards, or if parasitism involves marginal costs, the maximum number of eggs for which it is still profitable to superparasitize a host once more is limited. This number increases with the number of conspecifics searching in the patch. Large marginal costs (i.e. the expected gain of not parasitizing now) decrease the profit of superparasitism. For newly emerged parasitoids the rejection of an already parasitized host is not advantageous as long as the marginal costs of parasitism are small, because the host can never contain an egg of its own.
Many species of wireworms (larvae of click beetles, Elateridae) are polyphagous root herbivores. ... more Many species of wireworms (larvae of click beetles, Elateridae) are polyphagous root herbivores. In grasslands under restoration succession with various grass species, we aim to determine the role of wireworms in aboveground vegetation succession. Therefore, it is crucial to know whether wireworms prefer some food plants to others. We have investigated the root preference to different grass species for Agriotes obscurus and Athous haemorrhoidalis and whether these preferences can be explained by covariates. In Experiment 1, individual wireworms could choose between four different plants, one of each species (Anthoxanthum odoratum, Festuca rubra, Holcus lanatus, and Lolium perenne). In Experiment 2, groups of wireworms were released into the soil in the center of 16 plants (4 from each species). We used multinomial logit models (MLMs) to analze the data. In the appendix the use of multinomial response models is clarified with a fictitious example, using the SAS statistic software package. No preference was found in Experiment 1. In Experiment 2 we found differences in attractiveness of plant species depending on wireworm species: A. obscurus preferred grass species from nutrient-rich grasslands (L. perenne and H. lanatus). Both wireworm species disliked F. rubra. The distance from the release point influenced the probability of being found at a certain place at the end of the experiment: wireworms tended to stay in the proximity of the release point. A. haemorrhoidalis was more often found farther from the point of release than A. obscurus. Dispersal was farther
1. Carabids and other epigeal arthropods make important contributions to biodiversity, food webs ... more 1. Carabids and other epigeal arthropods make important contributions to biodiversity, food webs and biocontrol of invertebrate pests and weeds. Pitfall trapping is widely used for sampling carabid populations, but this technique yields biased estimates of abundance ('activitydensity') because individual activitywhich is affected by climatic factorsaffects the rate of catch. To date, the impact of temperature on pitfall catches, while suspected to be large, has not been quantified, and no method is available to account for it. This lack of knowledge and the unavailability of a method for bias correction affect the confidence that can be placed on results of ecological field studies based on pitfall data. 2. Here, we develop a simple model for the effect of temperature, assuming a constant proportional change in the rate of catch per°C change in temperature, r, consistent with an exponential Q 10 response to temperature. We fit this model to 38 time series of pitfall catches and accompanying temperature records from the literature, using first differences and other detrending methods to account for seasonality. We use meta-analysis to assess consistency of the estimated parameter r among studies. 3. The mean rate of increase in total catch across data sets was 0Ă0863 AE 0Ă0058 per°C of maximum temperature and 0Ă0497 AE 0Ă0107 per°C of minimum temperature. Multiple regression analyses of 19 data sets showed that temperature is the key climatic variable affecting total catch. Relationships between temperature and catch were also identified at species level. Correction for temperature bias had substantial effects on seasonal trends of carabid catches. 4. Synthesis and Applications. The effect of temperature on pitfall catches is shown here to be substantial and worthy of consideration when interpreting results of pitfall trapping. The exponential model can be used both for effect estimation and for bias correction of observed data. Correcting for temperature-related trapping bias is straightforward and enables population estimates to be more comparable. It may thus improve data interpretation in ecological, conservation and monitoring studies, and assist in better management and conservation of habitats and ecosystem services. Nevertheless, field ecologists should remain vigilant for other sources of bias.
This study is part of the program Enhanced Biodiversity, funded by the Earth and Life Sciences of... more This study is part of the program Enhanced Biodiversity, funded by the Earth and Life Sciences of the Dutch Scientific Organization (NWO-ALW, Project Number 014-22-031).We thank M. A. Keller for the use of his software to construct the kinetograms from the behavioral transition matrices. A. Willemsen from Noldus Information Technology is acknowledged for his kindness in giving us the opportunity to analyze our data with the most recent Theme version and for discussions. Correspondence concerning this article should be addressed to L.
Evaluation of lifetime productivity is sensible to target interventions for improving productivit... more Evaluation of lifetime productivity is sensible to target interventions for improving productivity of smallholder dairy systems in the highlands of East Africa, because cows are normally not disposed of based on productive reasons. Feeding strategies and involuntary culling may have long-term effects on productive (and therefore economic) performance of dairy systems. Because of the temporal scale needed to evaluate lifetime productivity, experimentation with feedstuffs in single lactations is not enough to assess improvements in productivity. A dynamic modelling approach was used to explore the effect of feeding strategies on the lifetime productivity of dairy cattle. We used LIVSIM (LIVestock SIMulator), an individual-based, dynamic model in which performance depends on genetic potential of the breed and feeding. We tested the model for the highlands of Central Kenya, and simulated individual animals throughout their lifetime using scenarios with different diets based on common fe...
Tuta absoluta (Meyrick), a key pest of tomato, is quickly spreading over the world and biological... more Tuta absoluta (Meyrick), a key pest of tomato, is quickly spreading over the world and biological control is considered as one of the control options. Worldwide more than 160 species of natural enemies are associated with this pest, and an important challenge is to quickly find an effective biocontrol agent from this pool of candidate species. Evaluation criteria for control agents are presented, with the advantages they offer for separating potentially useful natural enemies from less promising ones. Next, an aggregate parameter for ranking agents is proposed: the pest kill rate km. We explain why the predator's intrinsic rate of increase cannot be used for comparing the control potential of predators or parasitoids, while km can be used to compare both types of natural enemies. As an example, kill rates for males, females and both sexes combined of three Neotropical mirid species (Campyloneuropsis infumatus (Carvalho), Engytatus varians (Distant) and Macrolophus basicornis (St...
We have examined the effects of herbivore diversity on parasitoid community persistence and stabi... more We have examined the effects of herbivore diversity on parasitoid community persistence and stability mediated by nonspecific information from herbivore-infested plants. First, we investigated host location and patch time allocation in the parasitoid Cotesia glomerata in environments where host and/or nonhost herbivores were present on Brassica oleracea leaves. Parasitoids were attracted by infochemicals from leaves containing nonhost herbivores. They spent
Females of the larval parasitoid of Drosophila, Asobara citri, from sub-Saharan Africa, defend pa... more Females of the larval parasitoid of Drosophila, Asobara citri, from sub-Saharan Africa, defend patches with hosts by fighting and chasing conspecific females upon encounter. Females of the closely related, palearctic species Asobara tabida do not defend patches and often search simultaneously in the same patch. The effect of patch defence by A. citri females on their distribution in a multi-patch environment was investigated, and their distributions were compared with those of A. tabida. For both species 20 females were released from two release-points in replicate experiments. Females of A. citri quickly reached a regular distribution across 16 patches, with a small variance/mean ratio per patch. Conversely, A. tabida females initially showed a clumped distribution, and after gradual dispersion, a more Poisson-like distribution across patches resulted (variance/mean ratio was closer to 1 and higher than for A. citri). The dispersion of A. tabida was most probably an effect of exploitation: these parasitoids increasingly made shorter visits to already exploited patches. We briefly discuss hypotheses on the adaptive significance of patch defence behaviour or its absence in the light of differences in the natural history of both parasitoid species, notably the spatial distribution of their hosts.
The hemiparasite Striga hermonthica is a major constraint to smallholder farmer livelihoods and f... more The hemiparasite Striga hermonthica is a major constraint to smallholder farmer livelihoods and food security in subâSaharan Africa. A better understanding of its lifeâcycle can help developing more effective management strategies. Here, we studied density dependence in S. hermonthica on Sorghum bicolor. We exposed two genotypes of S. bicolor that differed in the level of tolerance and resistance to S. hermonthica to a range of seed densities of the parasite. We evaluated multiple host and parasite performance parameters through periodic, destructive harvests and related these to the initial seed density using model selection. Initially, the probability for attachment was positively densityâdependent, suggesting facilitation of new infections. However, at host maturity, S. hermonthica infection probability showed strong negative density dependence, indicating severe competition, in particular in the early developmental stages. Although parasite shoot dry weight showed a strong negative density dependence at host maturity, flower production per parasite exhibited positive density dependence again, suggesting compensation. The two host genotypes had similar responses to increased parasite densities, indicating differences between the genotypes in tolerance but not resistance. Consequently, despite density dependence in lifeâcycle components, the per capita reproductive output of S. hermonthica, Râ (flowersâseedâ»Âč) was densityâindependent. Apparently, management of the hemiparasite can neither benefit from a negatively densityâdependent bottleneck, nor from a positively densityâdependent Allee effect. The most promising suggestion to obtain S. hermonthica population decline (Rââ<â1) and longâterm control is to increase host shading by growing a vigorous, competitive crop.
Het doel van dit experiment is het bepalen van het effect van voedseltype op gewichtstoename. Om ... more Het doel van dit experiment is het bepalen van het effect van voedseltype op gewichtstoename. Om zoân effect vast te stellen op een wetenschappelijke manier, worden de gegevens geanalyseerd met de Wilcoxon tweesteekproeventoets
Ongoing human population growth and changing patterns of resource consumption are increasing glob... more Ongoing human population growth and changing patterns of resource consumption are increasing global demand for ecosystem services, many of which are provided by soils. Some of these ecosystem services are linearly related to the surface area of pervious soil, whereas others show non-linear relationships, making ecosystem service optimization a complex task. As limited land availability creates conflicting demands among various types of land use, a central challenge is how to weigh these conflicting interests and how to achieve the best solutions possible from a perspective of sustainable societal development. These conflicting interests become most apparent in soils that are the most heavily used by
Working Papers are interim reports on work of Mansholt Graduate School (MG3S) and have received o... more Working Papers are interim reports on work of Mansholt Graduate School (MG3S) and have received only limited reviews 1. Each paper is refereed by one member of the Editorial Board and one member outside the board. Views or opinions expressed in them do not necessarily represent those of the Mansholt Graduate School. The Mansholt Graduate School's researchers are based in two departments: 'Social Sciences' and 'Environmental Sciences' and two institutes: 'LEI, Agricultural Economics Research Institute' and 'Alterra, Research Institute for the Green World'. In total Mansholt Graduate School comprises about 250 researchers. Mansholt Graduate School is specialised in social scientific analyses of the rural areas and the agri-and food chains. The Graduate School is known for its disciplinary and interdisciplinary work on theoretical and empirical issues concerning the transformation of agriculture, rural areas and chains towards multifunctionality and sustainability. Comments on the Working Papers are welcome and should be addressed directly to the author(s).
Human activities such as land use and-management may strongly affect the soil's ability to provid... more Human activities such as land use and-management may strongly affect the soil's ability to provide ecosystem services, in which microbes are playing a key role. Because sampling is usually restricted to the topsoil, little is known about effects of land use on ecosystem functioning down the soil profile. The present study assessed the effects of different land use types (arable, forest, grassland) on soil microbial biomass, activity and community structure at different soil depths (A, AC, C horizons), under the same climatic and pedological conditions, in the Danube Floodplain in Austria. Microbial biomass was 4e5 times lower in the arable field than in forest and grassland in the upper horizons. Additionally, both microbial biomass and activity decreased 3e4 fold with soil depth in forest and grassland. However, up to 30% of total microbial biomass was found in the C horizon in the arable field. We found a differentiation of microbial community structure between land use types and with soil depth: i.e. strong differences in the topsoil between land uses, whereas community structure in the C horizon was similar. This study confirms that land use exerts strong effects on soil microbes in the topsoil and that microbial biomass and activity decrease with soil depth. However, considerable microbial biomass and activity are found below 30 cm depth which is usually not included in samplings. In the deeper soil horizon effects of land use disappear, with microbial community structure and functioning becoming similar in similar pedological conditions.
A stochastic model is formulated to determine the optimal strategy for a solitary parasitoid whic... more A stochastic model is formulated to determine the optimal strategy for a solitary parasitoid which has discovered an already parasitized host. The model assumes that the parasitoid can count both the number of eggs already present in a host and the number of conspecifics searching in the same patch. The survival probability of an egg is assumed to depend on the total number of eggs in a host. The decision to (super)parasitize depends both on the degree to which the discovered host already is parasitized and on the number of conspecific females searching in the same patch. We consider both the case that egg laying does not involve any costs for the parasitoid and the case that it involves some marginal costs. Uniform behaviour of all the conspecific parasitoids in a patch, i.e. laying one additional egg in all encountered larvae containing a particular number of eggs, appears to be a pure evolutionary stable strategy (ESS). If either the probability that a parasitoid emerges from a host decreases with an increasing degree of parasitism, at least from a particular number of eggs onwards, or if parasitism involves marginal costs, the maximum number of eggs for which it is still profitable to superparasitize a host once more is limited. This number increases with the number of conspecifics searching in the patch. Large marginal costs (i.e. the expected gain of not parasitizing now) decrease the profit of superparasitism. For newly emerged parasitoids the rejection of an already parasitized host is not advantageous as long as the marginal costs of parasitism are small, because the host can never contain an egg of its own.
Many species of wireworms (larvae of click beetles, Elateridae) are polyphagous root herbivores. ... more Many species of wireworms (larvae of click beetles, Elateridae) are polyphagous root herbivores. In grasslands under restoration succession with various grass species, we aim to determine the role of wireworms in aboveground vegetation succession. Therefore, it is crucial to know whether wireworms prefer some food plants to others. We have investigated the root preference to different grass species for Agriotes obscurus and Athous haemorrhoidalis and whether these preferences can be explained by covariates. In Experiment 1, individual wireworms could choose between four different plants, one of each species (Anthoxanthum odoratum, Festuca rubra, Holcus lanatus, and Lolium perenne). In Experiment 2, groups of wireworms were released into the soil in the center of 16 plants (4 from each species). We used multinomial logit models (MLMs) to analze the data. In the appendix the use of multinomial response models is clarified with a fictitious example, using the SAS statistic software package. No preference was found in Experiment 1. In Experiment 2 we found differences in attractiveness of plant species depending on wireworm species: A. obscurus preferred grass species from nutrient-rich grasslands (L. perenne and H. lanatus). Both wireworm species disliked F. rubra. The distance from the release point influenced the probability of being found at a certain place at the end of the experiment: wireworms tended to stay in the proximity of the release point. A. haemorrhoidalis was more often found farther from the point of release than A. obscurus. Dispersal was farther
1. Carabids and other epigeal arthropods make important contributions to biodiversity, food webs ... more 1. Carabids and other epigeal arthropods make important contributions to biodiversity, food webs and biocontrol of invertebrate pests and weeds. Pitfall trapping is widely used for sampling carabid populations, but this technique yields biased estimates of abundance ('activitydensity') because individual activitywhich is affected by climatic factorsaffects the rate of catch. To date, the impact of temperature on pitfall catches, while suspected to be large, has not been quantified, and no method is available to account for it. This lack of knowledge and the unavailability of a method for bias correction affect the confidence that can be placed on results of ecological field studies based on pitfall data. 2. Here, we develop a simple model for the effect of temperature, assuming a constant proportional change in the rate of catch per°C change in temperature, r, consistent with an exponential Q 10 response to temperature. We fit this model to 38 time series of pitfall catches and accompanying temperature records from the literature, using first differences and other detrending methods to account for seasonality. We use meta-analysis to assess consistency of the estimated parameter r among studies. 3. The mean rate of increase in total catch across data sets was 0Ă0863 AE 0Ă0058 per°C of maximum temperature and 0Ă0497 AE 0Ă0107 per°C of minimum temperature. Multiple regression analyses of 19 data sets showed that temperature is the key climatic variable affecting total catch. Relationships between temperature and catch were also identified at species level. Correction for temperature bias had substantial effects on seasonal trends of carabid catches. 4. Synthesis and Applications. The effect of temperature on pitfall catches is shown here to be substantial and worthy of consideration when interpreting results of pitfall trapping. The exponential model can be used both for effect estimation and for bias correction of observed data. Correcting for temperature-related trapping bias is straightforward and enables population estimates to be more comparable. It may thus improve data interpretation in ecological, conservation and monitoring studies, and assist in better management and conservation of habitats and ecosystem services. Nevertheless, field ecologists should remain vigilant for other sources of bias.
This study is part of the program Enhanced Biodiversity, funded by the Earth and Life Sciences of... more This study is part of the program Enhanced Biodiversity, funded by the Earth and Life Sciences of the Dutch Scientific Organization (NWO-ALW, Project Number 014-22-031).We thank M. A. Keller for the use of his software to construct the kinetograms from the behavioral transition matrices. A. Willemsen from Noldus Information Technology is acknowledged for his kindness in giving us the opportunity to analyze our data with the most recent Theme version and for discussions. Correspondence concerning this article should be addressed to L.
Evaluation of lifetime productivity is sensible to target interventions for improving productivit... more Evaluation of lifetime productivity is sensible to target interventions for improving productivity of smallholder dairy systems in the highlands of East Africa, because cows are normally not disposed of based on productive reasons. Feeding strategies and involuntary culling may have long-term effects on productive (and therefore economic) performance of dairy systems. Because of the temporal scale needed to evaluate lifetime productivity, experimentation with feedstuffs in single lactations is not enough to assess improvements in productivity. A dynamic modelling approach was used to explore the effect of feeding strategies on the lifetime productivity of dairy cattle. We used LIVSIM (LIVestock SIMulator), an individual-based, dynamic model in which performance depends on genetic potential of the breed and feeding. We tested the model for the highlands of Central Kenya, and simulated individual animals throughout their lifetime using scenarios with different diets based on common fe...
Tuta absoluta (Meyrick), a key pest of tomato, is quickly spreading over the world and biological... more Tuta absoluta (Meyrick), a key pest of tomato, is quickly spreading over the world and biological control is considered as one of the control options. Worldwide more than 160 species of natural enemies are associated with this pest, and an important challenge is to quickly find an effective biocontrol agent from this pool of candidate species. Evaluation criteria for control agents are presented, with the advantages they offer for separating potentially useful natural enemies from less promising ones. Next, an aggregate parameter for ranking agents is proposed: the pest kill rate km. We explain why the predator's intrinsic rate of increase cannot be used for comparing the control potential of predators or parasitoids, while km can be used to compare both types of natural enemies. As an example, kill rates for males, females and both sexes combined of three Neotropical mirid species (Campyloneuropsis infumatus (Carvalho), Engytatus varians (Distant) and Macrolophus basicornis (St...
We have examined the effects of herbivore diversity on parasitoid community persistence and stabi... more We have examined the effects of herbivore diversity on parasitoid community persistence and stability mediated by nonspecific information from herbivore-infested plants. First, we investigated host location and patch time allocation in the parasitoid Cotesia glomerata in environments where host and/or nonhost herbivores were present on Brassica oleracea leaves. Parasitoids were attracted by infochemicals from leaves containing nonhost herbivores. They spent
Females of the larval parasitoid of Drosophila, Asobara citri, from sub-Saharan Africa, defend pa... more Females of the larval parasitoid of Drosophila, Asobara citri, from sub-Saharan Africa, defend patches with hosts by fighting and chasing conspecific females upon encounter. Females of the closely related, palearctic species Asobara tabida do not defend patches and often search simultaneously in the same patch. The effect of patch defence by A. citri females on their distribution in a multi-patch environment was investigated, and their distributions were compared with those of A. tabida. For both species 20 females were released from two release-points in replicate experiments. Females of A. citri quickly reached a regular distribution across 16 patches, with a small variance/mean ratio per patch. Conversely, A. tabida females initially showed a clumped distribution, and after gradual dispersion, a more Poisson-like distribution across patches resulted (variance/mean ratio was closer to 1 and higher than for A. citri). The dispersion of A. tabida was most probably an effect of exploitation: these parasitoids increasingly made shorter visits to already exploited patches. We briefly discuss hypotheses on the adaptive significance of patch defence behaviour or its absence in the light of differences in the natural history of both parasitoid species, notably the spatial distribution of their hosts.
The hemiparasite Striga hermonthica is a major constraint to smallholder farmer livelihoods and f... more The hemiparasite Striga hermonthica is a major constraint to smallholder farmer livelihoods and food security in subâSaharan Africa. A better understanding of its lifeâcycle can help developing more effective management strategies. Here, we studied density dependence in S. hermonthica on Sorghum bicolor. We exposed two genotypes of S. bicolor that differed in the level of tolerance and resistance to S. hermonthica to a range of seed densities of the parasite. We evaluated multiple host and parasite performance parameters through periodic, destructive harvests and related these to the initial seed density using model selection. Initially, the probability for attachment was positively densityâdependent, suggesting facilitation of new infections. However, at host maturity, S. hermonthica infection probability showed strong negative density dependence, indicating severe competition, in particular in the early developmental stages. Although parasite shoot dry weight showed a strong negative density dependence at host maturity, flower production per parasite exhibited positive density dependence again, suggesting compensation. The two host genotypes had similar responses to increased parasite densities, indicating differences between the genotypes in tolerance but not resistance. Consequently, despite density dependence in lifeâcycle components, the per capita reproductive output of S. hermonthica, Râ (flowersâseedâ»Âč) was densityâindependent. Apparently, management of the hemiparasite can neither benefit from a negatively densityâdependent bottleneck, nor from a positively densityâdependent Allee effect. The most promising suggestion to obtain S. hermonthica population decline (Rââ<â1) and longâterm control is to increase host shading by growing a vigorous, competitive crop.
Het doel van dit experiment is het bepalen van het effect van voedseltype op gewichtstoename. Om ... more Het doel van dit experiment is het bepalen van het effect van voedseltype op gewichtstoename. Om zoân effect vast te stellen op een wetenschappelijke manier, worden de gegevens geanalyseerd met de Wilcoxon tweesteekproeventoets
Ongoing human population growth and changing patterns of resource consumption are increasing glob... more Ongoing human population growth and changing patterns of resource consumption are increasing global demand for ecosystem services, many of which are provided by soils. Some of these ecosystem services are linearly related to the surface area of pervious soil, whereas others show non-linear relationships, making ecosystem service optimization a complex task. As limited land availability creates conflicting demands among various types of land use, a central challenge is how to weigh these conflicting interests and how to achieve the best solutions possible from a perspective of sustainable societal development. These conflicting interests become most apparent in soils that are the most heavily used by
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