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Landscape moderation of biodiversity patterns and processes‐eight hypotheses
Abstract
Understanding how landscape characteristics affect biodiversity patterns and ecological processes at local and landscape scales is critical for mitigating effects of global environmental change. In this review, we use knowledge gained from human-modified landscapes to suggest eight hypotheses, which we hope will encourage more systematic research on the role of landscape composition and configuration in determining the structure of ecological communities, ecosystem functioning and services. We organize the eight hypotheses under four overarching themes. Section A: 'landscape moderation of biodiversity patterns' includes (1) the landscape species pool hypothesis-the size of the landscape-wide species pool moderates local (alpha) biodiversity, and (2) the dominance of beta diversity hypothesis-landscape-moderated dissimilarity of local communities determines landscape-wide biodiversity and overrides negative local effects of habitat fragmentation on biodiversity. Section B: 'landscape moderation of population dynamics' includes (3) the cross-habitat spillover hypothesis-landscape-moderated spillover of energy, resources and organisms across habitats, including between managed and natural ecosystems, influences landscape-wide community structure and associated processes and (4) the landscape-moderated concentration and dilution hypothesis-spatial and temporal changes in landscape composition can cause transient concentration or dilution of populations with functional consequences. Section C: 'landscape moderation of functional trait selection' includes (5) the landscape-moderated functional trait selection hypothesis-landscape moderation of species trait selection shapes the functional role and trajectory of community assembly, and (6) the landscape-moderated insurance hypothesis-landscape complexity provides spatial and temporal insurance, i.e. high resilience and stability of ecological processes in changing environments. Section D: 'landscape constraints on conservation management' includes (7) the intermediate landscape-complexity hypothesis-landscape-moderated effectiveness of local conservation management is highest in structurally simple, rather than in cleared (i.e. extremely simplified) or in complex landscapes, and (8) the landscape-moderated biodiversity versus ecosystem service management hypothesis-landscape-moderated biodiversity conservation to optimize functional diversity and related ecosystem services will not protect endangered species. Shifting our research focus from local to landscape-moderated effects on biodiversity will be critical to developing solutions for future biodiversity and ecosystem service management.
Supplementary resource (1)
... At the field scale, the impact of farming management* (*see Section 2.1 for definitions related to farming management considered in this review) on biodiversity has been widely studied, both in terms of direct effects (Jones et al. 2021) and the interaction of local farming management with landscape land cover (Tscharntke et al. 2012). For instance, biodiversity is impacted by farming systems, with greater diversity in organic fields than in non-organic ones (Lichtenberg et al. 2017). ...
... Indeed, given (i) the already recognized impact of farming management at the local scale on biodiversity and ecosystem services (e.g., Rusch et al. 2010) and (ii) the fact that most species move, complement, or supplement their resources in multiple patches across the landscape (e.g., Dunning et al. 1992;Greenstone et al. 1987;Petit et al. 2013), it seems highly likely that farming management will have direct and indirect impacts on biodiversity at the landscape scale. In fact, farming management at the landscape scale could influence mechanisms underlying biodiversity patterns and dynamics (Tscharntke et al. 2012). For example, the disturbances generated in fields by farming practices could have an impact on the movements of species in agricultural landscapes, thus affecting relationships within meta-communities (Leibold et al. 2004). ...
... The presence of organic fields in the landscape reduced the number of aphids in organic and nonorganic fields and decreased leaf blotch densities, but only in non-organic fields (Gosme et al. 2012). These results illustrate the existing interactions between local farming practices and the context of the agricultural landscape and could refer to the intermediate hypothesis of landscape complexity (Tscharntke et al. 2012). ...
Farming management and alterations in land cover play crucial roles in driving changes in biodiversity, ecosystem functioning , and the provision of ecosystem services. Whereas land cover corresponds to the identity of cultivated/non-cultivated ecosystems in the landscape, farming management describes all the components of farming activities within crops and grassland (i.e., farming practices, crop successions, and farming systems). Despite extensive research on the relationship between land cover and biodiversity at the landscape scale, there is a surprising scarcity of studies examining the impacts of farming management on biodiversity at the same scale. This is unexpected given the already recognized field-scale impact on biodiversity and ecosystem services, and the fact that most species move or supplement their resources in multiple patches across agricultural landscapes. We conducted a comprehensive literature review aimed at answering two fundamental questions: (1) What components of farming management are considered at the landscape scale? (2) Does farming management at the landscape scale impact biodiversity and associated ecosystem functions and services? We retrieved 133 studies through a query on the Web of Science, published from January 2005 to December 2021 addressing the broad notion of farming management at the landscape scale. The key findings are as follows: (1) The effect of farming management components at the landscape scale on biodiversity was tackled in only 41 studies that highlighted that its response was highly taxon-dependent. They reported positive effects of organic farming on pollinators, weeds, and birds, as well as positive effects of extensification of farming practices on natural enemies. (2) Most studies focused on the effect of organic farming on natural enemies and associated pests, and reported contrasting effects on these taxa. Our study underscores the challenges in quantifying farming management at the landscape scale, and yet its importance in comprehending the dynamics of biodiversity and related ecosystem services.
... Rather, supporting biodiversity in agroecosystems depends on maximizing the diversity of both seminatural and cropland cover resources through increased compositional and configurational heterogeneity. Shifts to intensive monocultures with large fields negatively impact species adapted to utilize resources across spatially heterogeneous systems, particularly specialist species (Gámez-Virués et al., 2015;Hua et al., 2024;Martin et al., 2019;Tscharntke et al., 2005Tscharntke et al., , 2012. Our results suggest that increased spatial heterogeneity in both crop and non-crop cover types can go some way to reverting or at least slowing down the negative effects of agricultural intensification on biodiversity. ...
... Our results on the effects of different components of spatial heterogeneity on biodiversity contribute to a more mechanistic understanding of the factors influencing biodiversity in agricultural landscapes. Higher crop or landscape compositional heterogeneity increases the variability between land-cover (or crop) types by incorporating diverse habitat types into the landscape that often harbour different wildlife communities compared to monocultures of similar size (Benton et al., 2003;Fahrig et al., 2011;Tews et al., 2004;Tscharntke et al., 2012). The presence of such a diverse array of habitats creates a wider range of spatially separated biotic and abiotic resources within the landscape (Fahrig et al., 2011;Tews et al., 2004). ...
... The presence of such a diverse array of habitats creates a wider range of spatially separated biotic and abiotic resources within the landscape (Fahrig et al., 2011;Tews et al., 2004). This resource diversity could play a crucial role in promoting biodiversity as many species rely on multiple resources provided by several different habitats throughout their life cycle, highlighting the importance of resource complementarity (Dunning et al., 1992;Fahrig et al., 2011;Mandelik et al., 2012;Tews et al., 2004;Tscharntke et al., 2012). Resource complementarity occurs F I G U R E 7 Estimated average Pearson's correlation coefficients among heterogeneity components and pest abundance (pest richness results were not interpreted due to the smaller number of studies, i.e., >5), with 90% (thicker bars) and 95% (thinner bars) confidence intervals (CIs). ...
Agricultural intensification not only increases food production but also drives widespread biodiversity decline. Increasing landscape heterogeneity has been suggested to increase biodiversity across habitats, while increasing crop heterogeneity may support biodiversity within agroecosystems. These spatial heterogeneity effects can be partitioned into compositional (land‐cover type diversity) and configurational heterogeneity (land‐cover type arrangement), measured either for the crop mosaic or across the landscape for both crops and semi‐natural habitats. However, studies have reported mixed responses of biodiversity to increases in these heterogeneity components across taxa and contexts. Our meta‐analysis covering 6397 fields across 122 studies conducted in Asia, Europe, North and South America reveals consistently positive effects of crop and landscape heterogeneity, as well as compositional and configurational heterogeneity for plant, invertebrate, vertebrate, pollinator and predator biodiversity. Vertebrates and plants benefit more from landscape heterogeneity, while invertebrates derive similar benefits from both crop and landscape heterogeneity. Pollinators benefit more from configurational heterogeneity, but predators favour compositional heterogeneity. These positive effects are consistent for invertebrates and vertebrates in both tropical/subtropical and temperate agroecosystems, and in annual and perennial cropping systems, and at small to large spatial scales. Our results suggest that promoting increased landscape heterogeneity by diversifying crops and semi‐natural habitats, as suggested in the current UN Decade on Ecosystem Restoration, is key for restoring biodiversity in agricultural landscapes.
... Land use change is considered a key global change driver affecting arthropod communities (Birkhofer et al., 2017). In particular, urbanisation and the loss of woody areas are two major processes that can erode abundance and diversity of arthropods (Forman & Baudry, 1984;Meyfroidt & Lambin, 2011;Tscharntke et al., 2005Tscharntke et al., , 2012 and potentially cause functional filtering (Correa-Carmona et al., 2022;Martinson & Raupp, 2013;Merckx et al., 2018;Schirmel et al., 2016;Simons et al., 2016). In addition, arthropod communities inhabiting different major land-use types of the temperate zone such as forests, managed grasslands or crops are likely to differ in their vulnerability to environmental changes. ...
... smaller species (but context-dependent trends in spiders), especially in more intensively managed and perturbed land-use types such as crops, as well as in landscapes characterised by a high degree of urbanisation. These findings are in agreement with expectations that landscape context can shape local arthropod communities (Tscharntke et al., 2005(Tscharntke et al., , 2012, and that frequent perturbations and less stable environments should benefit smaller species, which have been shown to cope better with diminished or more fluctuating resource availability (Eggenberger et al., 2019;Merckx et al., 2018;Peters, 1983), loss of environmental heterogeneity and reduced availability of microclimatic conditions. Potential underlying mechanisms are related to lower energetic costs and faster development and reduced risk of predation risk of small species (Fenoglio et al., 2021). ...
... Regarding our fourth prediction, we expected that arthropod species with higher dispersal capacities could cope better with more perturbed and fragmented habitats (Perović et al., 2018). Therefore, low dispersal capacity should be associated with higher vulnerability to such land-use modifications and face higher local extinction risks (Tscharntke et al., 2012;Wong et al., 2019). These predictions are partly supported by our study, showing long-term trends towards increased dispersal capacity of carabid communities in crops. ...
Understanding how anthropogenic activities induce changes in the functional traits of arthropod communities is critical to assessing their ecological consequences. However, we largely lack comprehensive assessments of the long‐term impact of global‐change drivers on the trait composition of arthropod communities across a large number of species and sites. This knowledge gap critically hampers our ability to predict human‐driven impacts on communities and ecosystems.
Here, we use a dataset of 1.73 million individuals from 877 species to study how four functionally important traits of carabid beetles and spiders (i.e. body size, duration of activity period, tolerance to drought, and dispersal capacity) have changed at the community level across ~40 years in different types of land use and as a consequence of land use changes (that is, urbanisation and loss of woody vegetation) at the landscape scale in Switzerland.
The results show that the mean body size in carabid communities declined in all types of land use, with particularly stronger declines in croplands compared to forests. Furthermore, the length of the activity period and the tolerance to drought of spider communities decreased in most land use types. The average body size of carabid communities in landscapes with increased urbanisation in the last ~40 years tended to decrease. However, the length of the activity period, the tolerance to drought, and the dispersal capacity did not change significantly. Furthermore, urbanisation promoted increases in the average dispersal capacities of spider communities. Additionally, urbanisation favoured spider communities with larger body sizes and longer activity periods. The loss of woody areas at the landscape level was associated with trait shifts to carabid communities with larger body sizes, shorter activity periods, higher drought tolerances and strongly decreased dispersal capacities. Decreases in activity periods and dispersal capacities were also found in spider communities.
Our study demonstrates that human‐induced changes in land use alter key functional traits of carabid and spider communities in the long term. The detected trait shifts in arthropod communities likely have important consequences for their functional roles in ecosystems.
... This lack of studies hampers our understanding of complex BEF relationships in fragmented natural ecosystems. In theory, habitat loss and fragmentation per se can regulate ecosystem function and the BEF relationship by altering species composition, interactions, and spatial asynchrony regardless of changes in species richness (Liu et al., 2018;Thompson and Gonzalez, 2016;Tscharntke et al., 2012). This is because species in communities are not ecologically equivalent and may respond differently to habitat loss and fragmentation per se, and contribute unequally to ecosystem function (Devictor et al., 2008;Wardle and Zackrisson, 2005). ...
... In our study, a possible mechanism for the positive impacts of fragmentation per se on plant diversity and above-ground productivity (indirect positive impact via plant diversity) is that fragmentation per se increases the habitat heterogeneity in the landscape, which can promote biodiversity through spatial asynchrony and spatial insurance effects (Tscharntke et al., 2012). Previous studies indicated that heterogeneity typically has nonlinear effects on BEF, as moderate heterogeneity can maximise spatial asynchrony (Redon et al., 2014;Wilcox et al., 2017). ...
... For a given level of habitat loss, the positive BEF relationship was strongest at moderate fragmentation per se level and became neutral at high fragmentation per se level. This can be explained by the increased spatial asynchrony at moderate fragmentation per se level, which can promote niche complementary among species in the community and thus strengthen the BEF relationship (Gonzalez et al., 2020;Thompson and Gonzalez, 2016;Tscharntke et al., 2012). The neutral BEF relationship at high fragmentation per se level may be due to edge effects enhancing environmental filtering, thereby leading to functional redundancy among species and decoupling the BEF relationship (Fetzer et al., 2015;Hu et al., 2016;Zambrano et al., 2019). ...
Habitat loss and fragmentation per se have been shown to be a major threat to global biodiversity and ecosystem function. However, little is known about how habitat loss and fragmentation per se alters the relationship between biodiversity and ecosystem function (BEF relationship) in the natural landscape context. Based on 130 landscapes identified by a stratified random sampling in the agro-pastoral ecotone of northern China, we investigated the effects of landscape context (habitat loss and fragmentation per se) on plant richness, above-ground biomass, and the relationship between them in grassland communities using a structural equation model. We found that habitat loss directly decreased plant richness and hence decreased above-ground biomass, while fragmentation per se directly increased plant richness and hence increased above-ground biomass. Fragmentation per se also directly decreased soil water content and hence decreased above-ground biomass. Meanwhile, habitat loss decreased the magnitude of the positive relationship between plant richness and above-ground biomass by reducing the percentage of grassland specialists in the community, while fragmentation per se had no significant modulating effect on this relationship. These results demonstrate that habitat loss and fragmentation per se have inconsistent effects on BEF, with the BEF relationship being modulated by landscape context. Our findings emphasise that habitat loss rather than fragmentation per se can weaken the positive BEF relationship by decreasing the degree of habitat specialisation of the community.
... For reconciling production and conservation in human-dominated landscapes, particularly important is understanding the scale and taxon dependence of biodiversity patterns as well as their relationships with components of spatial environmental heterogeneity (Azeria et al., 2009;Tscharntke et al., 2012;Landis, 2017). Scale issues in biodiversity studies in agricultural landscapes are not new, and most of them are founded, on the one hand, on extrapolation from results of local scale studies to the landscape scale and, on the other hand, on the lack of direct assessment of environmental heterogeneity (Fahrig et al., 2011), with relevant variables from each scale. ...
... Nowadays it has been recognized that traditional production lands are a mosaic landscape composed of agriculture patches, forest patches and patches with natural and semi-natural vegetation which interact among them, and where land-use and cover changes occur at different frequencies, magnitudes and time spans (Duelli, 1997;Watson et al., 2014). In these landscapes, species may inhabit different types of patches throughout their life cycles; they may be patch specialists or be successful in using different types of patches, sometimes disconnected across the landscape (Fischer et al., 2004;Fischer and Lindenmayer, 2006;Tscharntke et al., 2012). ...
... A cornerstone hypothesis for predicting and assessing biodiversity patterns in mosaic landscapes is environmental heterogeneity (Duelli, 1997;Benton et al., 2003), which, in its broad concept, assumes that biodiversity increases in heterogeneous environments because there are more niches and diverse ways of exploiting environmental resources. However, it has been also pointed out that the general pattern of the heterogeneity-diversity relationship should be humpe-shaped because increased heterogeneity will positively affect biodiversity up to some point, when the negative effects of fragmentation may outweigh the positive effects of heterogeneity, resulting in biodiversity declines (Fahrig et al., 2011, Allouche et al., 2012Tscharntke et al., 2012). Whether environmental heterogeneity elicits an increasing, decreasing or humped response of biodiversity will depend on a particular species or species group, on spatial scale and on type of agricultural land use and management (Tews et al., 2004;Fahrig et al., 2011). ...
In mosaic landscapes, environmental heterogeneity has been pointed out as an outstanding driver of emergent biodiversity patterns. Whether environmental heterogeneity elicits an increasing, decreasing or hump-shaped response of biodiversity depends on species, scale and type of agricultural land use and management. In this study, we analyzed ground-dwelling ant diversity in agroecosystems of Southern Dry Chaco (SDC) at local and landscape scales. We carried out the study along a gradient of agriculture intensification, taking into account five land-use and land-cover (LULC) classes: fallow lands, secondary forests, pastures, woody crops and herbaceous crops. We analyzed ant species richness and community composition in relation to local environmental heterogeneity as well as to landscape compositional heterogeneity. Changes in ant community composition were mainly related to species replacement along the LULC gradient, with fallow lands and secondary forests harboring the highest ant species richness. Biotic heterogeneity, promoted by vegetation, explained the pattern of ant diversity at local scale, whereas dissimilarity between neighboring LULC types explained ant species richness at landscape scale. Our findings highlight the importance of promoting natural and semi-natural vegetation as well as managing landscape compositional structure to enhance ant diversity in agroecosystems of the SDC.
... Across the globe, agricultural intensification has been the primary approach to increase crop yields and feed the growing human population (Maja and Ayano, 2021;Tscharntke et al., 2012). This process involves several changes applied at local and landscape scales, such as increasing chemical inputs and mechanizing agricultural practices, enlarging field sizes and reducing non-crop habitats (Emmerson et al., 2016;Tilman et al., 2001). ...
... Several groups of arthropods benefit from neighboring non-crop habitats and spill over to arable fields, enhancing ecosystem service provision (Blitzer et al., 2012). This spillover of arthropods can result from their periodic or annual movements across habitat edges (Blitzer et al., 2012;Tscharntke et al., 2012), leading to a substantial variation in community structures along the gradient from field edges towards arable field interiors (Fagan et al., 1999;González et al., 2016;Rand et al., 2006). Thus, cross-habitat movements of organisms can be crucial for promoting in-field diversity (Galpern et al., 2020;González et al., 2020a;Knapp et al., 2019) and ecosystem services such as biological control (Ollivier et al., 2020;Perović et al., 2018), pollination (Castro et al., 2021), and organic matter decomposition (Benbow et al., 2019). ...
Agricultural intensification and landscape simplification are among the major drivers of biodiversity loss in agricultural landscapes. Increasing field edges might be a key solution for enhancing biodiversity and related ecosystem services within arable fields. In this study, we investigated the spatial distribution of nine arthropod groups and weed seed and pest predation rates across different distances from field edges and crop types. Furthermore, we tested the relationship between local carabid abundance and species richness and directly measured weed seed and pest predation rates. Most of the investigated taxa were not affected by field margin proximity, except for carabid species richness and the abundance of bees and wasps, hoverflies, and myriapods, which were high near the edge. We found a higher abundance of carabids and herbivores in oilseed rape compared to other crops, while hoverflies, bees and wasps were more abundant in cereal. True bug abundance was significantly higher in oilseed rape interiors compared to edges. Weed seed predation and pest predation by small mammals were the highest at 36 m from the field margin, probably due to small mammal distribution, while pest predation by arthropods did not show any significant pattern. Both weed seed predation rate and arthropod pest predation were positively related to carabid abundance and negatively to species richness. Contrasting responses across nine investigated arthropod taxa indicate that redesigning agricultural landscapes to support biodiversity across taxa will be challenging, and further studies are needed to fully understand the spatial distribution of arthropods and related ecosystem services in agricultural landscapes.
... Therefore, understanding the extent to which ecotones support biodiversity is fundamental to making decisions about conservation priorities (Kark 2013) and for subsequent conservation planning (Mereta et al. 2012;Baselga 2012;KoubaY et al. 2014). Furthermore, such an approach allows us to design appropriate strategies not only on a large scale but also on a finer scale for the conservation of threatened or rare species (Tscharntke et al. 2012) that have restricted habitats in ecotones (Gaston 2000;Baselga 2010;Tscharntke et al. 2012;Zhang et al. 2014). ...
... Therefore, understanding the extent to which ecotones support biodiversity is fundamental to making decisions about conservation priorities (Kark 2013) and for subsequent conservation planning (Mereta et al. 2012;Baselga 2012;KoubaY et al. 2014). Furthermore, such an approach allows us to design appropriate strategies not only on a large scale but also on a finer scale for the conservation of threatened or rare species (Tscharntke et al. 2012) that have restricted habitats in ecotones (Gaston 2000;Baselga 2010;Tscharntke et al. 2012;Zhang et al. 2014). ...
... Although habitat characteristics have been extensively considered when studying species-environment interactions, in the last decades, these interactions have also been explored including the landscape-level perspective (Palmer et al., 2000;Hovel and Lipcius, 2001;Cole et al., 2012;Ricart et al., 2018), which usually implies observation at larger spatial scales, since landscapes are characterized by their composition of habitat types and their configuration or spatial arrangement (Turner, 2005;Dunning et al., 1992). Thus, the influence of landscape characteristics (e.g., habitat type, patch size, patch configuration) in a number of ecological mechanisms have been widely documented, showing that habitat-level processes can interact with landscape-level and also higher spatial scale processes to generate patterns of species distribution (Tscharntke et al., 2012;Staveley et al., 2017;Bustamante and Branch, 1996;Witman et al., 2004). ...
... After settling, habitat attributes will shape its abundance and composition, providing food and shelter, while landscape-level processes could influence recruitment or interspecific interactions (e.g., predation) but their potential influence will fade out with the mobility of the species promoting connectivity among habitat patches. This study contributes to the emerging evidence of the role of the interaction of processes acting at different scales in modulating the patterns of species coexistence and distribution which understanding is crucial to protect coastal biodiversity (Tscharntke et al., 2012;Staveley et al., 2017;Bustamante and Branch, 1996;Witman et al., 2004). ...
... Moreover, fragmentation reduces animal population sizes and disrupts animal movement and seed dispersal between fragments (Ibáñez et al., 2014;Morán-López et al., 2015). As a result, the landscape acts as an environmental filter for plant communities, making it challenging for species with larger fruits and seeds to disperse between fragments and decreasing their occurrence within the overall landscape, including in regenerating areas (Ewers and Didham, 2006;Tscharntke et al., 2012b). These species are primarily zoochorous (with seeds dispersed by animals) and shade-tolerant, and they play an important role in maintaining the carbon stocks of forest fragments (Coelho et al., 2022b). ...
... analyses to the landscape level gives a different picture, as landscape structure is the key driver of local biodiversity patterns and processes [28,29]. On a landscape scale, most studies find that single large habitat patches conserve fewer species than several small patches of the same cumulative area [18,27,30]. ...
The continuing biodiversity losses through agricultural expansion and intensification are dramatic. We argue that a mix of on- and off-field measures is needed, overcoming the false dichotomy of the land sharing-sparing debate. Protected land is essential for global biodiversity, while spillover between farmed and natural land is key to reducing species extinctions. This is particularly effective in landscapes with small and diversified fields. Focusing only on protected land fails to conserve a wealth of species, which often provide major ecosystem services such as pest control, pollination, and cultural benefits. On-field measures must minimise yield losses to prevent increased demand for food imports from biodiversity-rich regions, requiring enforcement of high social–ecological land-use standards to ensure a good life for all.
... To effectively protect saproxylic beetles in tree hollows not only knowledge of the beetles' habitat requirements at local scales is needed (see Ranius et al. 2009 Henneberg et al. 2021) but also a better understanding of how landscape composition at larger spatial scales in uences saproxylic beetle assemblages in tree hollows (Franc et al. 2007; Müller & Gossner 2010; Ranius et al. 2015). Landscape composition is considered a key factor explaining species richness patterns at different spatial scales (Tscharntke et al. 2012; Gonthier et al. 2014). Habitat availability at landscape scale has been shown to be of high importance for species assemblages in old trees (Sverdrup-Thygeson et al. 2014). ...
1. Veteran deciduous trees are a rare element in today’s central European managed forests due to intensive forest management over the last 200 years, resulting in a loss of dead wood habitats like tree hollows. Saproxylic beetle species depend on dead wood, and habitat specialists, such as species relying on tree hollows, are largely threatened.
2. To better understand how to protect saproxylic beetle assemblages in tree hollows at a landscape scale we collected beetles from tree hollows in three forest regions in Bavaria using emergence traps. We related landscape composition at spatial scales of 300–5000 m around the tree hollows to beetle diversity in the hollows using CORINE satellite data. We also modelled four dispersal-associated morphological traits as well as functional diversity indices of the beetles in relation to landscape composition.
3. The proportion of deciduous forest surrounding the tree hollows had positive effects on species richness of saproxylic beetles in two of the three study regions. Positive effects on threatened species were more pronounced than effects on total species richness at all spatial scales. Relationships between functional diversity and landscape composition only partly confirmed our expectations regarding better dispersal ability of beetles in isolated habitat patches.
4. Our study indicates that threatened saproxylic beetles react more sensitively to landscape compositional changes than common species. In the light of ongoing habitat fragmentation, efforts to protect threatened saproxylic beetle species should not only include single forest stands but focus on a landscape scale and support connectivity of forest patches.
... Moreover, fragmentation reduces animal population sizes and disrupts animal movement and seed dispersal between fragments (Ibáñez et al., 2014;Morán-López et al., 2015). As a result, the landscape acts as an environmental filter for plant communities, making it challenging for species with larger fruits and seeds to disperse between fragments and decreasing their occurrence within the overall landscape, including in regenerating areas (Ewers and Didham, 2006;Tscharntke et al., 2012b). These species are primarily zoochorous (with seeds dispersed by animals) and shade-tolerant, and they play an important role in maintaining the carbon stocks of forest fragments (Coelho et al., 2022b). ...
Secondary forests can play a critical role in conserving plant biodiversity and sequestering carbon. However, intensive past management, fragmentation, and initial soil fertility can hinder forest recovery during secondary succession, especially in terms of tree species selection. In turn, tree species selection can negatively impact soil fertility recovery and may slow down the succession process, but the direct and indirect effects between these factors remain unclear. To assess the complex interactions among landscape, previous management, soil and vegetation, 27 secondary forests of varying ages, previously used for eucalyptus plantations, located in diverse landscape configurations within the Atlantic Forest biome, were examined. Key variables, such as planting frequency, cutting frequency, forest cover in the landscape, patch isolation between fragments, functional richness, tree aboveground biomass (AGB), soil sum of bases, soil organic matter, and soil phosphorus concentration were used to construct a structural equation model to evaluate the direct and indirect effects of landscape and previous management on forest development. Cutting frequency and patch isolation had a negative direct effect on functional richness. Additionally, a strong positive direct effect of functional diversity on aboveground biomass and soil sum of bases was found. Thus, cutting frequency and patch isolation had negative indirect effects on biomass and soil sum of bases (a proxy for soil fertility), mediated by functional richness. These findings underscore the significance of integrating plant functional diversity into restoration strategies to preserve ecosystem functioning and efficiently recover biodiversity, tree biomass, and soil fertility in secondary forests.
... Landscape heterogeneity positively affects ecological systems, increasing the abundance and diversity of vascular plants [5], insects [6,7], spiders [8,9], birds [10], and mammals [11]. Grasslands, pastures, woodlands, and hedgerows are foraging and resting areas for beneficial biota, providing nectar sources for pollinators, prey for predators, and hosts for parasitoids, all of which are very scarce within disturbed habitats [12,13]. Furthermore, these semi-natural landscape elements can act as corridors or stepping stones, favouring the permeability of hostile environments [14][15][16][17]. ...
The simplification of agricultural landscapes that has occurred in recent decades has led to a consequent decline in biodiversity. The aim of this study was to investigate the role of cultivated and semi-natural areas to sustain the beta diversity of nocturnal Lepidoptera. A dataset available for an organic century-old olive farm was analysed. Sampling was carried out from July 2018 to June 2019 within eight sites. The beta diversity was explored using the Bray–Curtis quantitative similarity index. To assess the main process driving community composition, two measures of nestedness were calculated. The analyses showed that most species were more abundant in semi-natural sites, although some species were found to be barycentric or exclusive to the olive groves. The nestedness at farm and site scales confirmed that the main process driving the composition of the moth community was species impoverishment, but this process was not found to be significant when comparisons involved herbaceous semi-natural habitats and cultivated sites. We found out that the contribution of olive groves to the farm beta diversity was small but non-negligible. To improve the sustainable management of an olive grove, it is preferable to promote the presence of tree-covered areas since semi-natural herbaceous cover can be represented within the farm by low-input olive groves.
... No strong differences between years within vineyards, but significant differences between vineyards (p < 0.006). Top: NMDS borders 1 and 2. Bottom: NMDS borders 1 and 3. the interaction with landscape context (Tscharntke et al., 2012;Tuck et al., 2014). These differences could also be attributed to the degree of vegetation cover in the interrows, which has been shown to have positive impacts on birds, especially for those that nest there (Duarte et al., 2014;Buehler et al., 2017;Brambilla and Gatti, 2022). ...
Management under ecological schemes and increasing habitat heterogeneity, are essential for enhancing biodiversity in vineyards. Birds provide several contributions to agriculture, for example pest control, recreation and enhancing human mental health, and have intrinsic value. Birds are also ideal model organisms because they are easy to survey, and species respond differently to agricultural land use at different scales. Vegetated borders of crops are key for many species of birds, and distance to the border have been found to be an important factor in vineyard dominated agroecosystems. We evaluate if there are differences in the bird assemblage, between the interior compared to borders within vineyards, using a hierarchical community occupancy model. We hypothesized that occupancy of birds is greater in environments with greater heterogeneity, which in this study was considered to be contributed by the proximity to vegetated corridors. We expected that vineyard borders close to corridors will have higher bird occupancy than the center of the vineyard. The research was conducted in three vineyards with biodiversity-friendly management practices, in Gualtallary, Mendoza. Bird surveys were conducted over three breeding seasons from 2018 to 2020. Occupancy and richness of the bird community was more closely associated with the borders adjacent to the corridors than with the interior of the vineyards, as we initially predicted, although the assemblage of birds did not differ much. More than 75% of the registered species consume exclusively or partially invertebrates. Biodiversity-friendly management and ecological schemes, together with vegetated corridors provide multiple benefits for biodiversity conservation. These approaches not only minimize the use of agrochemicals but also prioritize soil cover with spontaneous vegetation, which supports a diverse community of insectivorous bird species, potentially contributing to pest control.
... Due to habitat alteration and loss, the species' current distribution is significantly reduced (Queirolo et al. 2011. In contrast to the contraction of the maned wolf's original distribution, the conversion of forest habitats to mosaics of pastures and agriculture created areas that favoured their expansion toward the densely forested areas of the Atlantic Forest, in south-eastern Brazil (Queirolo et al. 2011, Tscharntke et al. 2012, Nigro et al. 2020, Pereira et al. 2020, such as large forest blocks and protected areas. ...
We present new records of two threatened canid species, the bush dog (Speothos venaticus) and the maned wolf (Chrysocyon brachyurus), within and in the vicinity of Iguaçu National Park, Paraná, Brazil. These records were obtained through camera trap monitoring conducted between 2018-2020 and a wildlife rescue operation outside the park. The bush dog record was the first in a decade of camera trap monitoring, encompassing 20,297 trap days. This effort is comparable to that expended in detecting the species in other areas of the Atlantic Forest. The maned wolf records in the Atlantic Forest were unexpected, given the species' apparent avoidance of this habitat type. This presence may be attributed to significant landscape transformations , creating open areas conducive to the maned wolf's dispersion within the Atlantic Forest. These records highlight the importance of investigating the dispersal behaviors of the bush dog and the maned wolf in this region to understand the impact of human-altered landscapes on the geographical distribution of these two canids. These new records within and on the border of the Iguaçu National Park assume particular significance for enhancing and coordinating conservation initiatives for these species and establishing public policies for their conservation.
http://www.canids.org/CBC/25/Threatened_Canids_Brazil%20.pdf
... Par exemple il a fallu tester un mélange de variétés de riz résistante et sensible à la pyriculariose sur une surface de plus de 3000 ha pour démontrer l'efficacité des mélanges variétaux (Zhu et al. 2000). Un autre exemple est l'impact très important de la complexité du paysage sur l'efficacité des mesures agrienvironementales pour améliorer la biodiversité et les services éco-systémiques (Tscharntke et al. 2012) : dans un paysage d'agriculture intensive, le pool d'espèce régional est très faible et les habitats favorables mis en place ne sont pas colonisés. A l'autre extrême, dans un habitat très diversifié, la biodiversité est de toute façon très importante donc l'aménagement d'habitats favorables ne change rien (par exemple (Smits et al. 2012)). ...
... Only few organisms are adapted to intensively used agricultural landscapes, such as crop feeding insects or those adapted to high and continuing disturbance (Henle et al. 2004). The gross of species, however, cannot survive in highly intensified agricultural landscapes requiring natural or semi-natural landscapes (Henle et al. 2008;Guerrero et al. 2012;Tscharntke et al. 2012a;Lécuyer et al. 2022). ...
Increasing agricultural intensification, combined with land transformation and fragmentation, poses significant threats to biodiversity. While extensively cultivated landscapes serve as vital refuges against biodiversity loss, they are modified by land abandonment and intensification. Orchard meadows in Central Europe represent traditional extensive land management systems, exhibiting high biodiversity. Comprising cultivated grasslands and scattered fruit trees, orchard meadows feature structures rich in different habitats supporting a diverse flora and fauna. However, their decreasing economic importance in recent decades has resulted in severe degradation or abandonment. Despite their importance for biodiversity conservation, there remains no comprehensive overview of orchard meadow biodiversity and management in Central Europe. This review aims to summarize existing knowledge on orchard meadows’ role in biodiversity conservation and the effects of management practices on habitat diversity and quality at both smaller (structure and microhabitats, local scale) and larger scales (surrounding landscape, regional scale). The first part focuses on orchard meadow biodiversity, including both plants and animals and their link to landscape-scale factors. Biodiversity in orchard meadows is predominantly affected by patch size, determining species richness and composition, and connectivity to neighbouring orchard meadows, influencing species migration and recolonization success. The second part evaluates management impacts, illustrating differences in the benefits of mowing versus grazing across taxonomic groups. An intermediate management intensity for orchard meadows determines their conservation value in terms of species composition, varying among different taxonomic groups. To prevent area loss and abandonment of orchard meadows, we advocate for political and public support, along with incentives for farmers to maintain their biodiversity.
... In landscapes characterised by habitat loss, fragmentation and limited connectivity, species are not equally affected. In fact, degraded landscapes promote the invasion and expansion of species directly affected by the frequency of the relevant effect traits, whereas other species with response functional traits, that make them susceptible to disturbances, tend to be lost (Tscharntke et al., 2012). Therefore, in recent years, the study of functional traits has been incorporated into diversity assessments to address questions related to the consequences of environmental transformation on the functions performed by species in ecosystems. ...
Owing to the rapid and ongoing anthropogenic changes impacting ecosystem functions and their interplay with biodiversity, there is a growing focus on assessing insect functional diversity. This emphasis helps to unravel key roles of insects on ecosystem processes and to identify the assembly mechanisms that regulate species coexistence.
The ecological functions of phytophagous scarab beetles (Scarabaeidae) have been relatively unexplored, and potential functional traits are scattered throughout the literature. Species within this group exhibit diverse lifestyles, forms and sizes. They exploit various resources such as decomposing wood, foliage, roots and flowers, with a small subset identified as predators. Although many of their representatives are significant agricultural pests, information on their contributions in natural ecosystems has not been consolidated.
This study reviews the ecological functions potentially carried out by phytophagous scarab beetles and proposes functional traits to be incorporated into studies of functional diversity. Through this, the goal is to integrate the scattered information, stimulate the generation of questions that go beyond classical ecological theory and contribute to advancing our knowledge of their ecosystem functions, as well as the foundations for understanding community structure. We propose to use trophic groups to define functions such as bioturbation, organic matter decomposition, biological control and potential pollination.
A simplified list of functional traits was obtained by conducting correlation analyses using a trait matrix from a region in northern Colombia. This represents a significant advance for the study of traits within the framework of functional ecology, applicable to territorial planning and biodiversity conservation.
... Landscape characteristics and the presence of natural enemies of vector communities can indirectly influence viral prevalence, with more complex landscapes showing reduced PVY prevalence due to a decrease in species spillover [82,83]. In the plant host, vertical transmission begins with one infected cell, leading to systemic infection throughout the plant as the virus follows the distribution of photo-assimilates, thereby infecting new tubers and growing leaves [84]. ...
Potatoes are a cornerstone of global agriculture and a fundamental component of diets worldwide, with plant viruses accounting for nearly half of the emerging crop epidemics. Among these, Potato Virus Y (PVY) poses a formidable challenge to potato farming, leading to significant economic repercussions and threats to food security. Understanding the influence of climate on PVY is pivotal in tackling this viral menace. Climatic conditions, including temperature, precipitation, and humidity, play a key role in the behavior of aphids, the primary vectors of PVY, thereby impacting the disease's prevalence in potato fields. With climate change modifying these key weather variables, there's a looming risk of enhanced PVY spread and a shift in its geographical presence. Recognizing and adapting to these climate-induced changes is vital for formulating effective Review Article 40 strategies and sustainable practices to counter PVY's effects, safeguarding potato crops from this major viral threat. This analysis delves into the complex dynamics between climate change and PVY, focusing on how changes in weather patterns influence the virus's behavior and impact, with the aim of enhancing our preparedness and response to this agricultural challenge.
... In burned forests, for example, higher tree herbivory is related to a decrease in the abundance of predatory ants (Queiroz et al., 2022). Predatory insects usually decline with habitat conversions to agricultural landscapes (Tscharntke et al., 2012), but it is still unknown whether top-down control performed by predatory ants decreases in forest fragments surrounded by croplands. Ants are also important seed dispersers-seeds dispersed by ants are less exposed to granivores and have higher success rates (Gallegos et al., 2014;Giladi, 2006;Leal et al., 2015). ...
Land‐use changes and habitat fragmentation can alter biodiversity and associated ecosystem functions.
We investigated whether cropland expansion in south‐east Amazonia decreases ecosystem functions performed by ants and dung beetles by altering their communities.
We sampled both groups in two forest types, in south‐eastern Amazonia: undisturbed riparian forests and riparian forests surrounded by croplands. We sampled ants and dung beetles with epigaeic pitfall traps, and experimentally assessed seed removal and predation by ants, and faeces and seed removal by dung beetles.
Although ant and dung beetle abundance and richness did not differ across riparian forests, species composition of both groups did. Ants found seeds faster in undisturbed riparian forests, but the proportion of seed removal did not differ between forests. The abundance of predatory ants and the predation of termites by ants did not differ between forests.
Seed and dung removal by dung beetles did not differ across riparian forests. Despite the observed differences in dung beetle composition, we did not find the effects on ecosystem functions probably due a functional redundancy of species.
The quality of ecosystem functions provided by ants is lower in riparian forests surrounded by croplands, while changes in dung beetle diversity did not impact their ecosystem functions, with potential effects on the natural recovery of these disturbed riparian forests.
... In this context, biodiversity-friendly matrices, such as agroforestry systems, can have a vital impact on aiding the migration of species across fragmented habitats, simultaneously offering resources to alleviate the decline in biodiversity (Perfecto and Vandermeer, 2008). In fact, biodiversity-friendly matrices can be used as supplementary or complementary habitat for a wide range of native species, thus contributing to increased regional diversity (Dunning et al., 1992, Tscharntke et al., 2012. The loss and modification of natural habitats pose one of the greatest threats to the decline of amphibian and reptile species worldwide. ...
Global herpetofauna faces threats by habitat loss and degradation, with amphibian and reptile species maintenance in human-modified landscapes not only depending on forest remnants, but also on biodiversity-friendly matrices, such as agroforestry systems. Nevertheless, herpetological studies in agroforests are limited, hindering conservation decisions. To fill this gap, we conducted a global meta-analysis to assess the ability of agroforestry systems to maintain abundance and richness of amphibian and reptile species when compared to native forests. We analyze how community parameters (richness or abundance) and agroforest types based on the vegetation characteristics described by the studies (simplified or complex) impact the variation of overall effect size. We also used meta-regression models to examine how the amount of forest cover around agroforests affects the effect size. Finally, we calculated Sorensen's Index based on incidence data to investigate the degree of similarity in species composition of amphibians and reptiles between agroforestry systems and native forests. Our results showed that amphibian diversity in agroforests is lower than in native forests, regardless of the parameter and agroforestry type. For reptiles, agroforests showed higher abundance and similar species richness to forests. Simplified agroforestry systems support less reptile diversity than complex systems, which are more similar to forests. Interestingly, landscape forest amount modulates the ability of agroforests in maintain reptile richness. In fact, agroforests inserted in highly forested landscapes can harbor higher richness of reptiles than forests. We also found that half of the amphibian and reptile species observed in agroforests are different from those observed in native forests. Our findings highlights that agroforests cannot replace native forests because such systems harbor reduced abundance and species richness, especially amphibians, and a distinct species composition. However, when inserted in forested landscapes these agricultural systems can host rich reptile communities. Thus, preserving native forests and restoring deforested regions are crucial for herpetofauna conservation in human-modified landscapes.
... Bird species richness at the landscape scale and, to a lesser extent, butterfly species richness at the landscape scale, were related to a larger total area of EFAs with larger shares of collaborative landscape-targeted EFAs. This may be because collaborative landscape-targeted EFAs aim at increasing habitat connectivity, which may increase cross-habitat spillover within and from outside farmland (Albrecht et al., 2010;Tscharntke et al., 2012). Also, they aim at increasing habitat diversity, which has been shown to be critical for high biodiversity at the landscape scale, because different habitats may provide different niches and thereby support different species (Ben-Hur and Kadmon, 2020;Meier et al., 2022;Smith et al., 2022). ...
Ecological focus areas (EFAs) are a key element of European agri-environmental measures, which aim at mitigating the negative impact of intensive agricultural practices on biodiversity. They are mostly implemented at local scale, such as action-based EFAs (prescribed minimum biodiversity-friendly management) and result-based EFAs (prescribed minimum biodiversity outcome). Implementation at the landscape scale as part of a collabo-rative landscape-targeted approach is less frequent. There, farmers of a given region jointly determine where and which measures are implemented in order to create a biodiversity-friendly landscape. The effectiveness of the three different, but often intertwined approaches to promote farmland biodiversity, has hardly ever been studied. To this end, we analyzed data from 121 1-km 2 squares distributed across the Swiss agricultural landscapes. At local scale (10-m 2 units), we found that plant species richness was higher in all EFA categories compared to management units outside EFAs, but tended to be highest in result-based and in collaborative landscape-targeted EFAs. At landscape scale (1-km 2 units), plant species richness was positively related to a large total area of all EFAs, while butterfly and bird richness were positively related to a large total area of all EFAs with a high share of collaborative landscape-targeted EFAs. We conclude that while result-based, and especially collaborative landscape-targeted EFAs come along with higher transaction costs, they contribute substantially to farmland biodiversity at different spatial scales.
... The explanation is that organisms are often searching for other sources (food, mating, shelter, microclimate, among others) that are separated in space, in a phenomenon that is called "landscape complementation", which occurs when landscapes contain two or more non-replaceable and spatially separated resources, important for vertebrates such as moths, parasitoids, and bees. Moths such as E. cyparissias can seek sources other than host plants and leave natural habitats such as forests to coconut plantations (Tscharntke et al., 2012). Therefore, it would be effective for coconut palm producers to intensify the monitoring of the presence of coconut plants affected by E. cyparissias on the margins of riparian forest, as these are more likely to be attacked by this pest insect, as they have a high possibility to emerge from this type of habitat. ...
The leaf crown borer Eupalamides cyparissias (Fabricius, 1777) is an agricultural pest that deserves attention in the cultivation of coconut (Cocos nucifera L.) and other economically important palm trees (Areacaceae). Several studies address the use of geostatistics to understand the attack of pest insects in agriculture, but there are no studies on the spatial and temporal patterns of E. cyparissias in coconut trees. The presence or absence of the borer was verified monthly in all coconut plants of a plot measuring 12.5 hectares, from July 2018 to October 2020. The occurrence of the borer was verified by the appearance of two main symptoms in the coconut trees. Dispersion patterns of E. cyparissias were studied using semivariograms to determine the most suitable spatial distribution model for the species. Kriging maps were created. Exponential and spherical semivariogram models showed the best fit to the patterns of spatial dispersion of the borer, showing that the attack on the coconut plantation occurs in an aggregate, and in foci, with a range of 20 to 160 metres. The climatic data had no significant correlation with the infestation rate. These results show that geostatistics are an important tool to define reliable sampling plans for integrated pest management. It is useful to assess the spatial and temporal distribution of E. cyparissias
... − жовтий кластер -інтегрує наукові напрацювання у сфері урбаністичного розвитку задля забезпечення стійкості субнаціональних утворень. Узагальнення результатів наукових досліджень з найбільш цитованих наукових праць з визначеної проблематики [5][6][7][8][9][10][11][12][13][14] засвідчило превалювання цікавості науковців до визначення екологічних детермінант забезпечення резільєнтності територіальних громад, проте розгортання пандемії COVID-19 та її наслідки переконливо свідчать про необхідність врахування також факторів забезпечення громадського здоров'я у контексті посилення стійкості соціально-економічної системи громади та її резистентності до загроз та шоків різної етимології. З урахуванням того, що саме цей блок наукових досліджень є менш поширеним, що обумовлено його новизною, то подальші емпіричні напрацювання у цьому напрямку залишаються актуальними. ...
In the article it is developed a methodological toolkit for determining the temporal patterns of the influence of financial determinants and public health factors on the local community resilience in the context of overcoming the consequences of the COVID-19 pandemic, based on the use of panel data regression modeling (testing for the presence of a lag of up to 3 years). The practical approbation of the approach was carried out on the basis of a sample from 21 European countries for the period 2000-2021. The following indicators were chosen as local community resilience parameters (outcome indicators): level of tax revenue decentralization; the level of income decentralization (ratio of own incomes of local budgets to central government incomes); the level of expenditure decentralization (the ratio of own expenditures of local budgets to central government expenditures). The financial and infrastructural factors of public health, the impact of which on performance indicators was studied, are the following: the number of beds (per 1,000 people); capital expenditures for health care (% of GDP); current health care expenditures (% of GDP); domestic government health care expenditures (% of current health care expenditures); domestic private health care expenditures (% of current health care expenditures); out-of-pocket health care expenditures (% of current health care expenditures). Based on the results of the approbation of the developed approach, immediate drivers and inhibitors of ensuring local community resilience, as well as drivers and inhibitors of delayed action, were identified. The obtained results allow us to note that in the context of strengthening the financial resilience of local community, it is necessary to increase the number of hospital beds, as well as the volume of current expenditures on health care, and to ensure this growth mainly by the expenditures from private financial resources and out-of-pocket expenditures.
... While recognizing that the relationship between habitat area and biodiversity independent of configuration is not settled, we propose that just as biodiversity may be affected by the total amount of nearby habitat through the sample-area effect, population-level demographic parameters also may be influenced by landscape-level ecological relationships, where effect sizes and directions are averaged over nearby habitat conditions. We expect the relative importance of factors affecting brood parasitism to vary with species and the degree of alteration of the landscape (Turner et al. 2001;Tscharntke et al. 2012). Our goal was thus to compare evidence of established nest parasitism hypotheses and possible effects of vegetation diversity and habitat amount on brood parasitism in agricultural landscapes dominated by extensive row crop production. ...
Context
Prior research documented relationships between brown-headed cowbird (Molothrus ater) brood parasitism and edge effects, proximity of perches, and nest exposure. Those relationships have not been evaluated in agroecosystems containing extremes of fragmentation and vegetation diversity.
Objectives
We compared three existing hypotheses on how cowbirds locate host nests with two new hypotheses regarding habitat amount and vegetation diversity to determine how the configuration and location of agricultural conservation practices affect grassland bird nest parasitism rates and predicted rates for eight common conservation practices.
Methods
We assessed cowbird parasitism of grassland bird nests on corn and soybean farms in Iowa, USA, and measured perch proximity, nest exposure, edge effects, habitat amount, and vegetation diversity for each nest. We fit a global generalized linear mixed-effects model and compared importance of model parameters using odds ratios. We predicted parasitism likelihood for every subset model and averaged predictions to explore individual effects.
Results
The variables that most influenced parasitism rates included main effects for nest initiation day-of-season (OR = 0.71, CI95 = 0.60–0.84) and the landscape variables of distance to nearest crop edge (0.63, 0.51–0.76) and proportion of grass land cover within 660 m (0.75, 0.57–1.00). We found little support that perch proximity, nest exposure, or native vegetation diversity affected parasitism. We also assessed parasitism likelihood by conservation practice and found no significant differences.
Conclusions
Our results provide evidence to support the edge effect and habitat amount hypotheses, but not the nest exposure, vegetation diversity, or perch proximity hypotheses.
... For instance, the quality of provision of an ecosystem service may not only be based on its average provision over time, but also on its difference over time [60]. So It is important to assess the steadiness of ecosystem service provision in easy ecosystems, where losses of ecosystem resilience to disturbances can be predictable to be strongest [61]. In addition, lageffects of management decisions may make ecosystem service losses only apparent a long time after the anthropogenic involvement [3]. ...
The concept of ecosystem service (ES) was originally developed to illustrate the benefits that natural ecosystems generate for society and to raise awareness for biodiversity and ecosystem conservation. In recent years, geographical information systems (GIS) have become a powerful tool for mapping (ES) within a landscape, which visualizes spatial and temporal patterns and changes in ecosystems and their services. Mapping (ES) is necessary for the progress of strategies that will guarantee their future supply and to support the policies in a more effective way. The comprehensive literature review was conducted using international databases such as Elsevier, Springer, Wiley, and Google Scholar. We used key terms including 'mapping','maps’, ‘ES or ecosystem service, ‘ecosystem functions’, ‘landscape functions’, ‘evaluation of ES’, and ‘assessment of services’. To identify mapping ecosystem services and their challenges and opportunities. In total, 65 research papers were found first, of which 34 were selected for review. The most important challenges are insufficient generation of ES in the context of managed systems, the need to estimate associations among indicators of (ES) incomplete understanding of the nature of associations among services, and the lack of a general numerical outline to address these relations.
Biological pest control relies on interactions between herbivores and their natural enemies. Maintaining this ecosystem service requires considering herbivore and natural enemy interactions and their response to anthropogenic change at multiple scales. In this study, we used ecological networks to quantify the network structure of interactions between herbivorous insects and their parasitoids. We examined how herbivore host abundance, parasitism rates, and shifts in network structure relate to changes in local habitat management and landscape context. We sampled herbivores and parasitoids in Brassica oleracea plants at 22 urban gardens in the Central Coast of California. At each site, we measured local management characteristics (e.g., vegetation, ground cover, canopy cover) and quantified surrounding landscape composition (e.g., urban, natural, open, and agricultural cover). For the eight sites with large enough networks, we calculated three network structure metrics (interaction richness, vulnerability, and functional complementarity). We then used generalized linear and mixed models to examine relationships between herbivore host abundance, parasitism rates, garden management and landscape characteristics, and network metrics. We found that both local management and landscape composition influenced parasitism, while only local factors affected host abundance and network structure. Higher network interaction richness was marginally associated with enhanced parasitism rates for two host species and lower parasitism rates for one host species. Our results suggest that local garden management decisions may shift the structure of host–parasitoid networks, which may subsequently affect host parasitism rates, but outcomes for biological pest control will likely vary across host species.
Oil palm plantations are typically managed in a monoculture system over large areas. This system contributes to biodiversity loss and promotes pest outbreaks by reducing natural enemies. However, ecosystem functions in oil palm plantations vary spatially and temporally and can still support biodiversity under certain conditions.
We conducted a study on the species richness, abundance and species composition of natural enemies in oil palm plantations and investigated the factors influencing natural enemy communities in oil palm plantations at both local and landscape scales. We selected 12 sites in an oil palm plantation in Central Borneo, Indonesia, which were grouped into 4 sub‐areas based on the presence of natural habitats, which varied in local and landscape characteristics. Arthropods were sampled using canopy knockdown fogging with a pyrethroid insecticide.
Different taxa of natural enemies responded differently to changes in habitat characteristics within oil palm plantations. Species richness of spiders was not affected by either local or landscape scale, but their species composition was affected by oil palm tree age (local scale) and the total edge of dominant oil palm tree age (landscape scale). Ant species richness was influenced by the class area of natural habitat (landscape scale), whereas their species composition was not influenced by either local or landscape scale. On the other hand, species richness of parasitoid wasps was influenced by light intensity (local scale) and the variation of oil palm tree age within a landscape (landscape scale). However, their species composition was only affected by light intensity.
The results suggest that oil palm management practices need to consider both local and landscape scales to maintain biodiversity and biological control and to achieve sustainable management of oil palm plantations.
1. Landscape context influences wild bee abundance and diversity, alongside pollination-related services. Growing evidence supports the positive effects of landscape heterogeneity on bee diversity and fruit production for pollination-dependent crops in flatlands. However, little remains known about these relationships in mountainous environments where the landscape matrix surrounding crops is often more complex than in lowlands.
2. We conducted our study in apple orchards in South Tyrol, an Alpine region in Italy, using pan-traps, direct observations of visitation frequency and a pollinator exclusion experiment. We investigated the scale-dependent effects of landscape heterogeneity and other parameters on wild bee assemblages and the related pollination service they provide at five spatial scales (radius 100-2000 m).
3. We found that landscape heterogeneity positively affected the abundance and richness of wild bees, with the strongest effect at 500 m. We calculated a multi-diversity index, reflecting the land-use intensity based on the species richness of vascular plants, grasshoppers, butterflies, birds and bats. We identified a positive relationship between this multidiversity index and wild bee richness. Additionally, we found that visitation rate of wild bees was negatively affected by crop cover and that abundance of honeybees did not influence wild bee visitation rate or reproductive success. Finally, reproductive success was positively related to semi-natural habitat cover.
4. Landscape heterogeneity should be maintained in apple orchards to continue to reap the benefits of vital pollination-related services. Diversification strategies should be implemented to promote habitat diversity at small scales, even in regions with more than 80% of (semi-)natural habitats.
Improving marginal lands to overcome challenges in land use, such as land abandonment prevention and biodiversity conservation, has garnered increasing attention from policymakers and scientists. In the context of rehabilitating marginal lands, the consideration of edaphic arthropods becomes paramount due to their multifaceted roles within the soil. The productivity of marginal lands is influenced by a complex interplay of various interconnected factors, including nutrient balance, nutrient release capacity, soil acidity, organic matter content, soil structure, and water retention. The long-term functionality of these soil processes in agricultural lands is heavily reliant on the activities of arthropods inhabiting the soil environment. Soil-dwelling arthropods play a pivotal role in ecosystem functioning, notably in nutrient cycling, facilitating plant nutrient uptake, and regulating pest populations, which ultimately impacts plant health, physiology, and overall performance. Recognizing the ecological importance of soil arthropod biodiversity is critical in the development of a future sustainable agricultural strategy. The potential for better agricultural production on marginal lands can be achieved by incorporating their contributions into land management practices that maintain ecological balance and sustainability.
Evolutionary biology was previously considered a historical science with predictions about evolutionary trajectories believed to be near impossible. The development of high throughput sequencing and data analysis technologies has challenged this belief, and provided an abundance of data that yields novel insights into evolutionary processes. Evolutionary predictions are now increasingly being used to develop fundamental knowledge of evolving systems and/or to demonstrate evolutionary control. Here we investigate the factors that make evolutionary repeatability more or less likely to increase the accuracy of evolutionary predictions. We identify outstanding questions and provide a potential starting point to determine how evolutionary repeatability is affected by genetic relatedness.
Habitat loss and fragmentation are landscape transformations with profound impacts on biodiversity. Insects are particularly affected by these processes, with consequences for ecosystem services. In the Neotropics, the Chaco forest is one of the largest phytogeographic regions and has suffered critical deforestation rates in recent decades. For 20 years, we have studied the impact of these modifications on insect communities in Córdoba, Argentina, and the interaction between forests and adjacent crops. Here, we review 25 empirical studies of the influence of fragment area, forest cover, and edge habitats on different insect functional groups, ecological processes, and ecological networks in fragmented Chaco forests in central Argentina. Small fragments and landscapes with low proportions of forest cover were generally linked to impoverished insect communities across most functional groups. Fragment area reductions negatively affected aboveground processes such as herbivory and parasitoidism, whereas leaf litter decomposition and most network parameters were not affected. Edge effects were variable, favoring some insect groups (i.e., ground-dwelling arthropods and parasitoids) and parasitoidism rates. Moreover, intense insect movement between forests and crops increased ecosystem service provision near the forest. Our results indicate that fragmentation of Chaco forests has clear implications for potential changes in insect communities and ecosystem services. Maintaining forest remnants and promoting native forest plantations should be prioritized to guarantee insect biodiversity conservation.
The long-term and large-scale cause of habitat fragmentation and loss is determined by human intervention, primarily due to the expansion of agriculture and increase in deforestation and urbanization. In this chapter, we present case studies to discuss the effects of habitat fragmentation on insect diversity and change in Mexican tropical areas. In this context, insect assemblages have responded in varied and contrasting ways. First, butterfly diversity and abundance from tropical dry forest fragments ranging from 10 to 90% forest cover area responded negatively to habitat loss. Ants and dung beetles from tropical rainforest fragments and surrounding matrix features showed idiosyncratic (significant) responses to patch attributes (the case for hypogeic ants) and/or to landscape composition (the case for dung beetles). At a larger (national) scale, loss of primary vegetation had a significant effect on species composition of dragonflies and damselflies, yet this effect does not necessarily mirror the effects detected for species richness, which likely are driven by species turnover effects. Unveiling complex dynamics for many insect populations and spatial patterns of insect diversity in fragmented landscapes requires accounting for species-level trait effects and responses, along with monitoring of trends in habitat extent and fragmentation over a range of spatial scales.
Pollinator activity is affected by landscape‐scale flower availability, and by pollinator interactions with co‐occurring organisms. Of special interest are potentially detrimental effects of herbivores on the attractiveness of plants to pollinators. While insect herbivores are abundant in natural and agro‐ecosystems, the combined effect of herbivory and landscape floral resources on pollinator activity and the delivery of pollination services is little studied and understood. Here we investigated the combined effects of surrounding flower cover and aphid herbivory on pollination services in agricultural landscapes. We apply a resource landscape approach for mapping the spatial distribution of floral resources across landscapes, using neighbourhood modelling and empirical data on flower availability in specific land‐use types. In each of 25 Mediterranean landscapes spanning a gradient of land‐use intensity ranging from natural to agricultural, we established paired patches of potted aphid‐infested or aphid‐free phytometer plants Diplotaxis erucoides . In each patch, we recorded the activity of insects visiting flowers and subsequent seed set. We also recorded the relative abundance of flowers in dominant land‐use locales within a 1 km radius of each patch. Neighbourhood analyses revealed that plant–pollinator interactions in our study system are shaped by herbivory, distribution of floral resources across the landscape, and the interaction between these factors. We found a negative competitive effect of flower cover on pollinator activity and phytometer seed‐set; this effect was stronger on aphid‐infested than aphid‐free plants. The main pollinator guilds in the study sites (wild bees, honeybees and non‐bee pollinators) responded differently to these factors. Our results highlight the importance of combining a resource landscape approach with the exploration of interactions among different organisms, when mapping pollination services and identifying the scale at which pollinators respond to foraging resources.
Urban green infrastructure has historically been used for aesthetical purposes, making landscapes visually pleasant. More recently the green infrastructure in urban and sub- urban areas has started to be applied to help solve a broad range of problems that city dwellers are facing. These problems include natural disasters, overheating, excessive flows rainwater, biodiversity decline and food insecurity among others. Thus, implementation of green infrastructure as Nature-based Solutions has become increasingly popular. This trend is likely to continue in future as global climate change poses more and more changes to city dwellers. Urbanization and population growth are likely to drive implementation of urban green infrastructure across the globe and especially in the Global South, where impacts of the global heating are likely to be particularly strong. Implementation of green infrastructure may be developed either mostly for aesthetical purposes or as Nature-based Solutions or both. It is, however, important to note that the integrated approach is likely to have the greatest potential to meet global challenges. Furthermore, implementation of the green infrastructure is likely to have the greatest positive impact when implemented as a holistic system rather than individual elements. Thus, there is a clear need to evaluate opportunities for green infrastructure development that could simultaneously maximize aesthetic impact and effectiveness of the urban green and blue spaces to act as Nature-based Solutions. Here we illustrate some of the variables and system dynamics involved. Using a simplified model with specific focus on food supply, system structural analysis suggests that the urbanization variables commonly considered in urban design models are not closely connected with those that would provide long-term sustainability. The positive feedback between variables within each of these two groups and negative impacts between groups create barriers to their combined assessment for practical mitigation actions. The various sub-systems and an expanded variable set can ideally be addressed with a similar methodology. We also discuss opportunities for integration and provide recommendations for policy makers, city planners and other stakeholders involved in construction and management of urban landscapes
VielFalterGarten ist ein Citizen-Science-Projekt, das zusammen mit Bürgerinnen und Bürgern der Stadt Leipzig Tagfalter beobachtet, dokumentiert und wissenschaftlich auswertet (www.vielfaltergarten.de). Das Projekt läuft von 2020 bis voraussichtlich 2024 und ist ein Ver-bundprojekt zwischen dem Helmholtz-Zentrum für Umweltforschung – UFZ, dem Deutschen Zentrum für integrative Biodiversitätsforschung (iDiv) Halle-Jena-Leipzig, dem Bund für Um-welt und Naturschutz Deutschland (BUND) Leipzig und der Stadt Leipzig, Amt für Stadtgrün und Gewässer. Gefördert wird das Projekt im Bundesprogramm Biologische Vielfalt durch das Bundesamt für Naturschutz mit Mitteln des Bundesministeriums für Umwelt, Naturschutz, nukleare Sicherheit und Verbraucherschutz.
Cities provide opportunities for biodiversity conservation through the design of urban greenspaces as wildlife habitat. A significant proportion of urban public land is narrow linear road verges, though their small size and harsh environmental conditions (e.g. high soil temperatures) may limit their ability to support plants and animals.
We worked with a municipal government in a highly urbanised area to test whether conversion of standard road verges (e.g. lawn) to predominantly native understorey plants (forbs, grasses and shrubs) selected for their abilities to tolerate harsh growing conditions and provide habitat increased the abundance and richness of bees, butterflies and birds. We used a before‐after‐control‐impact experiment and characterised temporal dynamics of biodiversity responses 1 year prior to planting and 4 years post‐planting. We also tested whether traits known to influence species responses to urbanisation (body size and feeding specialisation) mediated responses to road verge plantings.
Bee species richness and abundance increased at experimental plantings in the first post‐planting year and remained stable thereafter despite fluctuations at control sites. Butterfly abundance but not richness increased, and there was no evidence of bird responses to plantings.
Larger bee species, which are known to be most negatively impacted by urbanisation, benefited more from the road verge plantings, while there was no effect of feeding specialisation. Bird and butterfly traits did not mediate responses to plantings.
Synthesis and applications . Road verges comprise a significant proportion of urban green spaces, and our results suggest that despite their small sizes and harsh environmental conditions they can provide habitat for bees and to a lesser extent butterflies. We demonstrated that habitat value can be rapidly enhanced by converting standard road verges to native understorey plants and that these benefits may be greatest for the bee species most negatively impacted by urbanisation. Modifications such as additional plant species or wider verges may be required for urban road verges to provide habitat for a greater range of taxa including birds and butterflies.
Agricultural simplification continues to expand at the expense of more diverse forms of agriculture. This simplification, for example, in the form of intensively managed monocultures, poses a risk to keeping the world within safe and just Earth system boundaries. Here, we estimated how agricultural diversification simultaneously affects social and environmental outcomes. Drawing from 24 studies in 11 countries across 2655 farms, we show how five diversification strategies focusing on livestock, crops, soils, noncrop plantings, and water conservation benefit social (e.g., human well-being, yields, and food security) and environmental (e.g., biodiversity, ecosystem services, and reduced environmental externalities) outcomes. We found that applying multiple diversification strategies creates more positive outcomes than individual management strategies alone. To realize these benefits, well-designed policies are needed to incentivize the adoption of multiple diversification strategies in unison.
Understanding how the mammalian diversity responds to anthropogenic disturbances on local and landscape scales is an urgent task. The Atlantic Forest biome, with only 12% of its original area remaining, still harbors great diversity of small mammals (Rodentia and Didelphimorphia), a key group that responds quickly to disturbances. Here, using the largest dataset of Atlantic Forest small mammals, we evaluate how forest amount and bioclimatic variables affect the non-volant small mammal diversity. For this purpose, we use 214 small mammal assemblages across the Atlantic Forest domain. Our results show that forest amount, with a positive relation, was the most important predictor explaining the diversity of small mammals in Atlantic Forest remnants. We also found that the bioclimatic variables (temperature and precipitation) can positively and/or negatively affect small mammal biodiversity, depending on the region analyzed. This is the first study that has assessed diversity across the entire Atlantic Forest biome, showing the importance of large-scale assessment and of forest amount and bioclimatic variables in shaping the diversity of small mammals regardless of the biogeographic context.
Species distributions are a product of both current spatial configuration of habitats and legacies of historic land use. Therefore, effectiveness of agri-environment schemes, Payment for Ecosystem Service policies, and conservation management all hinge on understanding the relative importance of, and interactions among, current and historic drivers of species distributions. Here, we explore the combined effects of spatial spillovers and temporal legacies, both within and between habitat types. We use Bayesian hierarchical occupancy models with data on 373 species from four taxa (ground beetles, birds, vascular plants, small terrestrial mammals) from a chronosequence of 134 woodlands in temperate agricultural landscapes. Both spillovers and legacies affect species richness and community composition and, critically, these effects appear to interact. Real-world combinations of spillovers and legacies result in different biodiversity responses compared to the individual drivers in isolation. Woodland patches in landscapes with more old woodland and lower amounts of historical woodland loss tend to host more birds and plant species, but fewer small mammals. Failing to account for these drivers, particularly legacy effects, gives a distorted view of habitat suitability. In consequence, the same management actions may result in unexpectedly different outcomes depending on the spatial and historical context within the landscape.
Fruits and vegetables can vary significantly in their dependence upon insect pollinators to transfer pollen. Raspberry and blackberry are two fruits that are regarded as highly-pollinator dependent. This means that knowledge of pollinator foraging behaviour, efficiency at transferring pollen, and interactions between pollinators, flowers, and the surrounding environment, are all critical factors to understand in depth to ensure that pollination service delivery is optimised. Bees have generally been acknowledged as the most important crop pollinators, yet their efficiency can vary in response to various factors including timing of the visit, previous visits, hive health, flowers available and interactions with other taxa. Further, even though we know other insects visit crop flowers, little is known about the pollination services provided by animals other than bees (i.e., non-bees) and their capacity to transfer pollen effectively. We also have a limited understanding about the number and quality of flower visits required in different cultivars and systems to achieve the best fruit quality. Finally, the resources pollinators require in different seasons and landscapes and the environmental conditions in which berry plants are grown, can also mediate the likelihood of pollination success. This presentation will outline a number of research findings that could be used to support greater resiliency with regard to insect pollination needs of Rubus and Ribes. These include understanding the contribution of different flower visitors and their efficiency in providing pollination services, a greater understanding of pollinator resource needs to improve their longevity in orchard environments, the conditions in which plants are most responsive to pollination service delivery and the importance of collaborations between industry and researchers to manage the system sustainably and to optimise fruit production and quality.
The cabbage stem flea beetle (Psylliodes chrysocephala) is a significant pest of rapeseed (Brassica napus). Feeding by adult P. chrysocephala can cause severe leaf damage and larval infestation can reduce stem strength, both of which impact crop growth and development, causing substantial yield losses and economic damage. The structure of the agricultural landscape can regulate herbivorous pest populations through top-down and bottom-up processes. This has shown promise in regulating the populations of other herbivorous pests, but remains relatively unexplored for P. chrysocephala. Here we investigate how the structure of the agricultural landscape influences P. chrysocephala abundance (pest pressure) and associated crop damage. We also examine the effect of the landscape on natural enemies and their ability to regulate P. chrysocephala populations. We show that P. chrysocephala populations are primarily regulated through bottom-up processes. We identify adjacency to another rapeseed crop and the total proportion of rapeseed grown in the landscape as key factors influencing beetle pressure, crop damage, and larval infestation, but find no effect of host crop proportions grown in the previous year at the examined scales up to 1 km surrounding focal crops. We also observe positive effects of crop heterogeneity and semi-natural habitat proportions on natural enemy abundance and diversity; however, these increases had no direct impact on P. chrysocephala. Bottom-up processes appear to contribute to herbivorous pest regulation by diluting beetles in the landscape, and could represent an important mechanism for sustainably managing pest populations by adapting the proportions and neighbourhoods of rapeseed crops at small to large spatial scales.
Riparian buffer strips and their effects on insects
Critical thresholds are transition ranges across which small changes in spatial pattern produce abrupt shifts in ecological responses. Habitat fragmentation provides a familiar example of a critical threshold. As the landscape becomes dissected into smaller parcels of habitat, landscape connectivity-the functional linkage among habitat patches-may suddenly become disrupted, which may have important consequences for the distribution and persistence of populations. Landscape connectivity depends not only on the abundance and spatial patterning of habitat, but also on the habitat specificity and dispersal abilities of species. Habitat specialists with limited dispersal capabilities presumably have a much lower threshold to habitat fragmentation than highly vagile species, which may perceive the landscape as functionally connected across a greater range of fragmentation severity. To determine where threshold effects in species' responses to landscape structure are likely to occur, we developed a simulation
Conserving biodiversity requires identifying and addressing the myriad of problems generated when humans exploit natural resources. This chapter first explores ways in which priorities for both conservation action and research emerge and are evaluated. Effective conservation depends on identifying priorities for specific research and/or action. The first route is more reactive and involves the detection, through surveillance monitoring, of a change in status of a taxon, species group, habitat or ecosystem. The second route is more proactive and works by identifying potential threats that may cause significant negative changes in the future. Recognizing that conservation is ultimately a societal process underpinned by values and beliefs, the chapter describes how decisions about resource allocation for conservation actions can be informed by explicit use of scientific evidence in decision-making frameworks. The chapter ends by outlining future challenges to the development of decision-making frameworks for conservation that encompass policy, management and research
Conceptual approaches used to understand conservation in fragmented landscapes are summarized in this chapter by Andrew F. Bennett and Denis A. Saunders. Destruction and fragmentation of habitats are major factors in the global decline of species, the modification of native plant and animal communities and the alteration of ecosystem processes. Habitat destruction, habitat fragmentation (or subdivision) and new forms of land use are closely intertwined in an overall process of landscape change. Landscape change is not random: disproportionate change typically occurs in flatter areas, at lower elevations and on more-productive soils. Altered physical processes (e.g. wind and water flows) and the impacts of human land-use have a profound influence on fragments and their biota, particularly at fragment edges. Different species have different ecological attributes (such as scale of movement, life-history stages, what constitutes habitat) which influence how a species perceives a landscape and its ability to survive in modified landscapes. Differences in the vulnerability of species to landscape change alter the structure of communities and modify interactions between species (e.g. pollination, parasitism). Changes within fragments, and between fragments and their surroundings, involve timelags before the full consequences of landscape change are experienced. Conservation in fragmented landscapes can be enhanced by: (i) protecting and increasing the amount of habitat: (ii) improving habitat quality; (iii) increasing connectivity; (iv) managing disturbance processes in the wider landscape; (v) planning for the long term; and (vi) learning from conservation actions undertaken.
Author Summary
The world is currently experiencing a rapid loss of species, prompting investigation into the role of biodiversity on the functioning of ecosystems. Many recent studies have shown that high diversity of plants, pollinators, and predators is related to high plant growth, pollination, and predation, respectively. Many of these studies involved controlled experiments, yet results were highly variable, indicating that the environment may affect the relationship between species diversity and these ecosystem functions. In a heterogeneous environment, different species can occupy different microhabitats, or use different resources. This reduces competition between species, and can mean that diverse assemblages perform their ecosystem functions at elevated rates. Here we examine rates of three important functions in different natural, nonexperimental ecosystems: plant biomass production in German grasslands, parasitism rates across five habitat types in coastal Ecuador, and coffee pollination in agroforestry systems in Indonesia. We demonstrate that the effect of diversity on these processes increases in environments where limiting resources (soil nutrients, host insects, and coffee flowers, respectively) are spatially heterogeneous. These real world patterns, combined with previous experiments suggest that biodiversity may have its greatest impact on the functioning of diverse, naturally heterogeneous ecosystems.
Farmland birds have suffered significant declines in the last decades due to agricultural intensification. Agri-environment schemes (AES) aim to reverse this process by promoting “nature friendly” practises at the field-scale. AES based on the habitat requirements of target species have usually been successful, but the concurrence of species groups with contrasting habitat requirements (guilds) makes the design of successful measures for the whole bird community difficult. The effectiveness of AES is also constrained by landscape and regional effects not addressed by its field-scale application. Effects acting at different spatial scales could differ among bird species depending on basic life-history traits such home range size and landscape perception, which should covary with body size. We are not aware, however, of any study which investigates whether relative effects at different spatial scales could vary predictably within bird guilds. We analyse whether relative effects of within-field (including AES application), landscape and regional factors on open-land birds differ according to body size. Large birds were mostly affected by regional and landscape factors, whereas for small birds landscape and within-field factors were important. Hence, relative effects at changing spatial scales showed predictable variation according to bird size within this endangered and specialised farmland guild. These size-dependent effects should be taken into account for the design of more effective, integrated multi-scale strategies for the conservation of farmland birds.
We propose a protocol for assessing the ecological impacts of edge effects in fragments of natural habitat surrounded by induced (artificial) edges. The protocol involves three steps: (1) identification of focal taxa of particular conservation or management interest, (2) measurement of an ‘edge function’ that describes the response of these taxa to induced edges, and (3) use of a ‘Core-Area Model’ to extrapolate edge function parameters to existing or novel situations. The Core-Area Model accurately estimates the total area of pristine habitat contained within fragments. Moreover, it can be used to predict the amount of unaltered habitat preserved within any hypothetical fragment, such as a planned park or nature reserve, regardless of its size or shape. The model is simple, requiring two edge function parameters and the area and perimeter length of the fragment. Model simulations revealed that for any edge-sensitive species and habitat type there exists a critical range of fragment sizes in which the impacts of edge effects increase almost exponentially. This critical size range cannot be predicted without empirical measurement of the edge function.
Censuses were made of breeding birds on islands in Pymatuning Lake, a reservoir at the Pennsylvania-Ohio border. For these islands the variation of the number of resident avian species with island size is that which one would expect if the birds were distributed randomly, with the probability of a breeding pair residing on an island proportional to the area of the island and independent of the presence of other pairs. This type of random placement of individuals can yield species-area relations which differ from those commonly used for analysis of biogeographic data. -from Authors
Most ecological processes and interactions depend on scales much larger than a single habitat, and therefore it is important to link spatial patterns and ecological processes at a landscape scale. Here, we analyzed the effects of landscape context on the distribution of bees (Hymenoptera: Apoidea) at multiple spatial scales with respect to the following hypotheses: (1) Local abundance and diversity of bees increase with increasing proportion of the surrounding seminatural habitats. (2) Solitary wild bees, bumble bees, and honey bees respond to landscape context at different spatial scales. We selected 15 landscape sectors and determined the percentage of seminatural habitats and the diversity of habitat types at eight spatial scales (radius 250-3000 m) by field inspections and analyses of vegetation maps using two Geographic Information Systems. The percentage of semi- natural habitats varied between 1.4% and 28%. In the center of each landscape sector a patch of potted flowering plants (four perennial and two annual species) was placed in the same habitat type, a grassy field margin adjacent to cereal fields. In all, 865 wild bee individuals and 467 honey bees were observed and an additional 475 individuals were caught for species identification. Species richness and abundance of solitary wild bees showed a close positive correlation with the percentage of seminatural habitats at small scales up to 750 m, whereas bumble bees and honey bees did not respond to landscape context at these scales. In contrast, honey bees were correlated with landscape context at large scales. The densities of flower-visiting honey bees even increased with decreasing proportion of seminatural habitats at a radius of 3000 m. We are not aware of any empirical studies showing contrasting foraging patterns related to landscape context at different spatial scales. We conclude (1) that local landscape destruction affects solitary wild bees more than social bees, possibly changing mutualistic plant-pollinator and competitive wild bees- honey bees interactions and (2) that only analyses of multiple spatial scales may detect the importance of the landscape context for local pollinator communities.
Most large herbivores require some type of management within their habitats. Some populations of large herbivores are at the brink of extinction, some are under discussion for reintroduction, whilst others already occur in dense populations causing conflicts with other land use. Large herbivores are the major drivers for forming the shape and function of terrestrial ecosystems. This 2006 book addresses the scientifically based action plans to manage both the large herbivore populations and their habitats worldwide. It covers the processes by which large herbivores not only affect their environment (e.g. grazing) but are affected by it (e.g. nutrient cycling) and the management strategies required. Also discussed are new modeling techniques, which help assess integration processes in a landscape context, as well as assessing the consequences of new developments in the processes of conservation. This book will be essential reading for all involved in the management of both large herbivores and natural resources.
It is argued that community ecology should provide useful knowledge for managing ecological interactions and biological resources sustainably. In the context of managing biodiversity and ecosystem services in human-dominated landscapes, a theoretical and historical background to metacommunity ecology (Chapter 5) is presented and some case studies showing the interplay between theory and applied questions in agricultural landscape ecology are discussed. Several expectations from metacommunity theory on the effects of land use intensification are suggested, based on the fact that both local and regional processes are important for diversity and ecosystem functioning. Some rules of thumb for landscape management based on metacommunity theory and empirical studies are suggested: maintain local conditions by management; manage whole landscapes and not only single patches; maintain diversity of local conditions in region; maintain connections between patches without homogenizing landscape; maintain disturbance regimes close to natural.
The field of refuge design per se did not really exist until 1971. This is not to say that there were no wildlife refuges, national parks or game reserves, or that no thought was given to their situation and management. Even a nation as young and development orientated as the United States established its first national park in 1872 and its National Park System as early as 1916 (Stone, 1965), while in Europe and Asia hunting reserves of the aristocracy served the same goals as national parks (maintenance of wildlife) centuries earlier.
This book had its origin when, about five years ago, an ecologist (MacArthur) and a taxonomist and zoogeographer (Wilson) began a dialogue about common interests in biogeography. The ideas and the language of the two specialties seemed initially so different as to cast doubt on the usefulness of the endeavor. But we had faith in the ultimate unity of population biology, and this book is the result. Now we both call ourselves biogeographers and are unable to see any real distinction between biogeography and ecology.
Ask airline passengers what they see as they gaze out the window, and they will describe a fragmented landscape: a patchwork of desert, woodlands, farmlands, and developed neighborhoods. Once-contiguous forests are now subdivided; tallgrass prairies that extended for thousands of miles are now crisscrossed by highways and byways. Whether the result of naturally occurring environmental changes or the product of seemingly unchecked human development, fractured lands significantly impact the planet's biological diversity. In Ecology of Fragmented Landscapes, Sharon K. Collinge defines fragmentation, explains its various causes, and suggests ways that we can put our lands back together. Researchers have been studying the ecological effects of dismantling nature for decades. In this book, Collinge evaluates this body of research, expertly synthesizing all that is known about the ecology of fragmented landscapes. Expanding on the traditional coverage of this topic, Collinge also discusses disease ecology, restoration, conservation, and planning. Not since Richard T. T. Forman's classic Land Mosaics has there been a more comprehensive examination of landscape fragmentation. Ecology of Fragmented Landscapes is critical reading for ecologists, conservation biologists, and students alike. © 2009 The Johns Hopkins University Press. All rights reserved.
The number and variety of statistical techniques for spatial analysis of ecological data are burgeoning and many ecologists are unfamiliar with what is available and how the techniques should be used. This book provides an overview of the wide range of spatial statistics available to analyze ecological data, and provides advice and guidance for graduate students and practicing researchers who are either about to embark on spatial analysis in ecological studies or who have started but need guidance to proceed. © M.-J. Fortin and M.R.T. Dale 2005 and Cambridge University Press 2009.
A metacommunity consists of several local communities connected by dispersal. A metacommunity perspective helps to synthesize community ecology across spatial scales, and provides insights into the spatial mechanisms causing variation in species coexistence, strengths of species interactions and patterns of local and regional diversity. For example, while increasing the rate of dispersal among habitats can often lead to higher diversity of species, high dispersal can also homogenize the variation among communities (e.g. lower among-site variation (β-diversity) and increase predation intensity. An explicit consideration of scale, and, in particular, the relationship between local (α-diversity) and regional (γ-diversity), as mediated through β-diversity, will provide insights into the mechanisms underlying the structure of metacommunities. Finally, an explicitly spatial perspective must recognize the potential importance of movement of organisms and materials across traditional taxonomic (e.g. different trophic levels) and ecosystem (e.g. aquatic, terrestrial) boundaries.
Landscapes are frequently seen as fragments of natural habitat surrounded by a 'sea' of agriculture. But recent ecological theory shows that the nature of these fragments is not nearly as important for conservation as is the nature of the matrix of agriculture that surrounds them. Local extinctions from conservation fragments are inevitable and must be balanced by migrations if massive extinction is to be avoided. High migration rates only occur in what the authors refer to as 'high quality' matrices, which are created by alternative agroecological techniques, as opposed to the industrial monocultural model of agriculture. The authors argue that the only way to promote such high quality matrices is to work with rural social movements. Their ideas are at odds with the major trends of some of the large conservation organizations that emphasize targeted land purchases of protected areas. They argue that recent advances in ecological research make such a general approach anachronistic and call, rather, for solidarity with the small farmers around the world who are currently struggling to attain food sovereignty. Nature's Matrix proposes a radically new approach to the conservation of biodiversity based on recent advances in the science of ecology plus political realities, particularly in the world's tropical regions. © Dr Ivette Perfecto, Dr John Vandermeer and Dr Angus Wright, 2009. All rights reserved.
This book is the second of two volumes in a series on terrestrial and marine comparisons, focusing on the temporal complement of the earlier spatial analysis of patchiness and pattern (Levin et al. 1993). The issue of the relationships among pattern, scale, and patchiness has been framed forcefully in John Steele’s writings of two decades (e.g., Steele 1978). There is no pattern without an observational frame. In the words of Nietzsche, “There are no facts… only interpretations.”
This book provides a comprehensive, up-to-date synthesis of what is known about soil biodiversity and the factors that regulate its distribution, as well as the functional significance of below-ground biodiversity for ecosystem form and function. It describes the vast diversity of biota that live in the soil environment - the most complex habitat on Earth - and discusses the factors that act as determinants of this diversity across different spatial and temporal scales. This book also considers how biotic interactions in soil influence the important soil processes of decomposition and nutrient cycling. It demonstrates how interactions and feedbacks between diverse plant and soil communities act as important drivers of ecosystem form and function. The importance of these relationships for understanding how ecosystems respond to global change phenomena, including climate change, is discussed in depth. Much is still to be learned about the soil biota and their roles in ecosystems, and the author highlights some of the many challenges that face ecologists in the exploration of soil. This book provides an introduction to the biology of soil, and also discusses the most recent developments in this progressive field of ecology. The importance of soil biotic interactions for community and ecosystem ecology is illustrated through the use of numerous examples and case studies.
This chapter discusses herbivore–natural enemy interactions in fragmented and continuous forests. Studies of forest insect population dynamics have generally taken two approaches, using either long-term life-table data from a single forest stand or data from several widely separated sites, where each site is treated as a replicate population and a composite picture of the dynamics is inferred from the multiple sties. Under each hypothesis, the effect of fragmentation is to uncouple the forest tent caterpillar population from the parasite/pathogen community associated with population collapse. At each sample point in the megagrid and mesogrid, one estimates forest tent caterpillar's abundance and several discrete mortality factors. The spatial pattern of defoliation provides a detailed record of caterpillar abundance, from which one can measure the spread of increasing populations and the contraction of declining populations. Cocoons from isolated patches were less likely to be parasitized than those from continuous forest and the effect was much stronger for parasitism by P. pachypyga than for S. aldrichi. Two of the parasitic flies that attack forest tent caterpillar, Sarcophaga aldrichi and Patelloa pachypyga , are affected in different ways by forest fragmentation. The large-scale pattern of prolonged outbreaks of tent caterpillar in fragmented boreal forests in Ontario could result from a variety of mechanisms, including the reduced efficiency of parasitoids and a reduction in parasitoid movement in response to herbivore abundance in fragmented forests. Ultimately, population dynamics studies will need to be placed within the landscape framework for dynamics to be fully understood.
1. We measured beta diversity, or turnover in species composition, in each of 15 taxa (including plants, vertebrates and invertebrates), along two common transects: N-S and W-E arrays of 50X50 km squares across Britain. Comparing taxa, we asked whether high beta diversity is associated with poor powers of dispersal. Within taxa, we asked whether turnover increases consistently with geographic distance. 2. Beta diversity on this scale was found to be low in all groups. Total (transect) species richness increased by only 3-13% per 50X50 km square, relative to the average value of local (within-square) richness; or by 0.6-6% per square, relative to the maximum value of local richness. Among taxa, beta diversity showed no tendency to be higher in poorer dispersers. 3. In nearly all taxa, beta diversity as defined by Whittaker (1960) increased linearly with distance on the N-S transect. However, this was shown to be largely the effect of gradients in alpha (local, within-square) diversity. Moreover, distance is highly correlated with environmental (climatic) dissimilarity, providing an alternative explanation for distance effects. 4. We conclude that in the British biota, turnover at this scale is more the product of range and habitat restriction than of dispersal limitation; and that turnover is a relatively minor component of regional diversity, because of the predominance of strong gradients in alpha diversity.
Losing a single species from an ecosystem may have large effects on community and ecosystem properties, but this may depend on characteristics of the species and the ecosystem. We examined the effect of losing a single species on productivity and nitrogen retention in experimental grassland communities, concentrating on how these effects varied with the functional identity of the species lost and the diversity and composition of the community from which it was lost. In one experiment, we constructed random plant assemblages that varied in species richness to measure the effect of diversity alone on productivity and nitrogen retention. In another experiment, we constructed plant assemblages to assess the effects of deleting an individual plant species from assemblages differing in their functional and species richness and composition. On average, as species richness declined, productivity decreased but nitrogen retention was unaffected. However, the magnitude and direction of change in ecosystem functioning with declining diversity depended on the identity of the species deleted and the composition of the community from which it was deleted. The functional identity of a species predicted the type of impact its loss had on productivity, but not on nitrogen retention.
Beneficial arthropods, including native bees, predators, and parasitoids, provide valuable ecosystem services worth $8 billion to US agriculture each year. These arthropod-mediated ecosystem services (AMES) Include crop pollination and pest control, which help to maintain agricultural productivity and reduce the need for pesticide inputs. Maximizing survival and reproduction of beneficial arthropods requires provision of pollen and nectar resources that are often scarce in modern agricultural landscapes. Increasingly, native plants are being evaluated for this purpose. Native plants can outperform recommended non-natives and also provide local adaptation, habitat permanency, and support of native biodiversity. We predict that the success of insect conservation programs using flowering plants to increase AMES on farmland will depend on landscape context, with the greatest success in landscapes of moderate complexity. Reintegration of native plants into agricultural landscapes has the potential to support multiple conservation goals, and will require the collaboration of researchers, conservation educators, and native plant experts.
It is argued that the problem of pattern and scale is the central problem in ecology, unifying population biology and ecosystems science, and marrying basic and applied ecology. Applied challenges, such as the prediction of the ecological causes and consequences of global climate change, require the interfacing of phenomena that occur on very different scales of space, time, and ecological organization. Furthermore, there is no single natural scale at which ecological phenomena should be studied; systems generally show characteristic variability on a range of spatial, temporal, and organizational scales. The observer imposes a perceptual bias, a filter through which the system is viewed. This has fundamental evolutionary significance, since every organism is an "observer" of the environment, and life history adaptations such as dispersal and dormancy alter the perceptual scales of the species, and the observed variability. It likewise has fundamental significance for our own study of ecological systems, since the patterns that are unique to any range of scales will have unique causes and biological consequences. The key to prediction and understanding lies in the elucidation of mechanisms underlying observed patterns. Typically, these mechanisms operate at different scales than those on which the patterns are observed; in some cases, the patterns must be understood as emerging form the collective behaviors of large ensembles of smaller scale units. In other cases, the pattern is imposed by larger scale constraints. Examination of such phenomena requires the study of how pattern and variability change with the scale of description, and the development of laws for simplification, aggregation, and scaling. Examples are given from the marine and terrestrial literatures.
The species pool hypothesis is applied here to the interpretation of ‘hump-shaped’ (unimodal) species richness patterns along gradients of both habitat fertility and disturbance level (the habitat templet). A ‘left-wall’ effect analogous to that proposed for the evolution of organismal complexity predicts a right-skewed unimodal distribution of historical habitat commonness on both gradients. According to the species pool hypothesis, therefore, the distribution of opportunity for net species accumulation (speciation minus extinction) should also have a corresponding unimodal central tendency on both habitat gradients. Two assumptions of this hypothesis are illustrated with particular reference to highly fertile, relatively undisturbed habitats: (i) such habitats have been relatively uncommon in space and time, thus providing relatively little historical opportunity for the origination of species with the traits necessary for effective competitive ability under these habitat conditions; and (ii) species that have evolved adaptation to these habitats are relatively large, thus imposing fundamental ‘packing’ limitations on the number of species that can ‘fit’ within such habitats. Based on these assumptions, the species pool hypothesis defines two associated predictions that are both supported by available data: (a) resident species richness will be relatively low in highly fertile, relatively undisturbed contemporary habitats; and (b) species sizes within regional floras should display as a right-skewed unimodal (log-normal) distribution. The latter is supported here by an analysis of data for 2,715 species in the vascular flora of northeastern North America.
Landscape simplification has been clearly demonstrated to have negative impacts on the in-crop density and biological-control activity of natural enemies in agricultural landscapes. The role of spatial arrangement of the landscape, however, has not been investigated in agroecosystems. We applied cost–distance modeling to investigate the relationship between the in-crop density of natural enemies and the structural connectivity of non-crop land uses surrounding crops within Australian cotton landscapes. We further compared the explanatory power of this approach with the more commonly used spatially specific proportional-area approach, which considers landscape composition in terms of the proportional area of a given land use within a given radius. Cost–distance metrics offered a more significant explanation of in-crop density for the predatory beetle Dicranolaius bellulus (Coleoptera: Melyridae) than did the proportional-area approach. The in-crop density for this species was positively and significantly correlated with the connectivity of wooded land uses within a 3000 m radius. However, for natural enemy taxa that responded to landscape characteristics at smaller spatial scales (within a 750 m radius), namely Oxyopes spp. (Araneae: Oxyopidae) and Trichogramma spp., (Hymenoptera: Trichogrammatidae), the proportional-area approach gave a more significant explanation of in-crop density. Herbivore taxa responded weakly to proportional area at all scales and showed no correlation to cost–distance metrics. Findings indicate potential for simplified agricultural landscapes to be ‘selectively’ manipulated to enhance colonization of the crop by natural enemies, but not herbivores, by improving connectivity between crops and non-crop resources, through the presence of woody vegetation.
Under the current scenario of rapid human population increase, achieving efficient and productive agricultural land use while conserving biodiversity is a global challenge. There is an ongoing debate whether land for nature and for production should be segregated (land sparing) or integrated on the same land (land sharing, wildlife-friendly farming). While recent studies argue for agricultural intensification in a land sparing approach, we suggest here that it fails to account for real-world complexity. We argue that agriculture practiced under smallholder farmer-dominated landscapes and not large-scale farming, is currently the backbone of global food security in the developing world. Furthermore, contemporary food usage is inefficient with one third wasted and a further third used inefficiently to feed livestock and that conventional intensification causes often overlooked environmental costs. A major argument for wildlife friendly farming and agroecological intensification is that crucial ecosystem services are provided by “planned” and “associated” biodiversity, whereas the land sparing concept implies that biodiversity in agroecosystems is functionally negligible. However, loss of biological control can result in dramatic increases of pest densities, pollinator services affect a third of global human food supply, and inappropriate agricultural management can lead to environmental degradation. Hence, the true value of functional biodiversity on the farm is often inadequately acknowledged or understood, while conventional intensification tends to disrupt beneficial functions of biodiversity. In conclusion, linking agricultural intensification with biodiversity conservation and hunger reduction requires well-informed regional and targeted solutions, something which the land sparing vs sharing debate has failed to achieve so far.
Ecological findings on small spatial or temporal scales often do not extrapolate to larger scales (Wiens 1989; Kareiva 1990; Horne and Schneider 1995; Englund and Cooper 2003). This empirical pattern has a parallel in ecological theory. In many model systems, the rules devised for population dynamics on small spatial or temporal scales can be quite different from those that emerge on large scales (Levin 1992). For example, in models of host-parasitoid systems, the highly unstable Nicholson-Bailey model might describe local population dynamics, but combined with spatial environmental variation, these local-scale instabilities may give rise to dynamics on the larger spatial scale described by the potentially highly stable host-parasitoid models of Bailey et al. ( 1962) and May ( 1978). Indeed, theoretical examples abound where the rules assumed on a small scale lead to contrasting outcomes on a larger scale, including changes in stability properties of single species models, conversion of competitive exclusion into competitive coexistence, and more mundane cases simply involving changes in quantitative features of models, such as mean densities (Chesson 2001).
Scale transition theory focuses on the mechanisms by which the rules for population dynamics on local scales become modified to produce different rules for dynamics on larger spatial scales. Many of the specific issues discussed here as part of scale-transition theory pervade analyses of spatial ecological models, including models formally identified as metacommunity models. The difference here is the focus on the interaction between nonlinearity in local population dynamics and spatial variation as the explanation of the important outcomes on larger spatial scales. In essence, the material presented here implies a research program in which the interaction between nonlinearities and spatial variation is explored for its mechanistic and biological content. Nonlinearities often arise from specific biological postulates such as the nature of interactions within and between species (Chesson 200 l ). The properties of these nonlinearities identify the kinds of patterns of spatial variation that are important to outcomes at the scale of the whole system.
Understanding global biodiversity patterns requires analyses at multiple spa- tial and temporal scales, across a variety of different habitat types. We used a highly replicated study in coastal Ecuador to examine simultaneously for the first time spatial and temporal species turnover and the contribution of five different habitat types (rice, pasture, coffee agroforests, abandoned coffee agroforests, and native forest fragments) to regional diversity in the tropics, using the experimental placement of standardized nesting structures for bees and wasps. There was notable overlap in the communities of different habitat types, indicating that even intensively managed land can provide a valuable contribution to the overall biodiversity of the landscape mosaic. Importantly, there was a significant effect of habitat type on temporal variation in diversity. While intensive cropping systems such as rice and pasture exhibited higher diversity in certain months, greater species turnover through time in the abandoned coffee and forest plots accounted for the higher overall diversity in these habitats. Overall, spatial and temporal turnover explained 38.6% and 23.1%, respectively, of partitioned regional species richness. A quantitative analysis re- vealed that the relative habitat specificity of Hymenoptera decreased with increasing habitat disturbance.
The pervasive influence of island biogeography theory on forest fragmentation research has often led to a misleading conceptualization of landscapes as areas of forest/habitat and 'non-forest/non-habitat' and an overriding focus on processes within forest remnants at the expense of research in the human-modified matrix. The matrix, however, may be neither uniformly unsuitable as habitat nor serve as a fully-absorbing barrier to the dispersal of forest taxa. In this paper, we present a conceptual model that addresses how forest habitat loss and fragmentation affect biodiversity through reduction of the resource base, subdivision of populations, alterations of species interactions and disturbance regimes, modifications of micro- climate and increases in the presence of invasive species and human pressures on remnants. While we acknowledge the importance of changes associated with the forest remnants themselves (e.g. decreased forest area and increased isolation of forest patches), we stress that the extent, intensity and permanence of alterations to the matrix will have an overriding influence on area and isolation effects and emphasize the potential roles of the matrix as not only a barrier but also as habitat, source and conduit. Our intention is to argue for shifting the examination of forest fragmentation effects away from a patch-based perspective focused on factors such as patch area and distance metrics to a landscape mosaic perspective that recognizes the importance of gradients in habitat conditions.
All terrestrial ecosystems consist of an explicit producer subsystem and a decomposer subsystem. While traditionally these components have usually been considered in isolation from one another, they are obligatory dependent upon each other. Producers provide the organic carbon sources that drive the decomposer community and decomposer activity is in turn responsible for mineralizing nutrients required for maintaining growth of the producers. Mutualists, herbivores, pathogens and parasites affect producer-decomposer interactions both by directing changes in the flow of energy and resources, and by imposing selective forces that lead to evolutionary changes in individual producer and decomposer populations. The direct and indirect interactions between above-ground and below ground communities therefore have the potential to operate as major drivers of population-, community- and ecosystem-level processes (Hooper et al. 2000; Van der Putten et al. 2001; Wardle 2002).
Aboveground and belowground species interactions drive ecosystem properties at the local scale, but it is unclear how these relationships scale-up to regional and global scales. Here, we discuss our current knowledge of aboveground and belowground diversity links from a global to a local scale. Global diversity peaks towards the Equator for large, aboveground organisms, but not for small (mainly belowground) organisms, suggesting that there are size-related biodiversity gradients in global aboveground–belowground linkages. The generalization of aboveground–belowground diversity relationships, and their role in ecosystem functioning, requires surveys at scales that are relevant to the organisms and ecosystem properties. Habitat sizes and diversity gradients can differ significantly between aboveground and belowground organisms and between ecosystems. These gradients in biodiversity and plant community trait perception need to be acknowledged when studying aboveground–belowground biodiversity linkages.