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Managing agricultural landscapes to support biodiversity conservation requires profound structural changes worldwide. Often, discussions are centered on management at the field level. However, a wide and growing body of evidence calls for zooming out and targeting agricultural policies, research, and interventions at the landscape level to halt and reverse the decline in biodiversity, increase biodiversity-mediated ecosystem services in agricultural landscapes, and improve the resilience and adaptability of these ecosystems. We conducted the most comprehensive assessment to date on landscape complexity effects on nondomesticated terrestrial biodiversity through a meta-analysis of 1,134 effect sizes from 157 peer-reviewed articles. Increasing landscape complexity through changes in composition, configuration, or heterogeneity significatively and positively affects biodiversity. More complex landscapes host more biodiversity (richness, abundance, and evenness) with potential benefits to sustainable agricultural production and conservation, and effects are likely underestimated. The few articles that assessed the combined contribution of linear (e.g., hedgerows) and areal (e.g., woodlots) elements resulted in a near-doubling of the effect sizes (i.e., biodiversity level) compared to the dominant number of studies measuring these elements separately. Similarly, positive effects on biodiversity are stronger in articles monitoring biodiversity for at least 2 y compared to the dominant 1-y monitoring efforts. Besides, positive and stronger effects exist when monitoring occurs in nonoverlapping landscapes, highlighting the need for long-term and robustly designed monitoring efforts. Living in harmony with nature will require shifting paradigms toward valuing and promoting multifunctional agriculture at the farm and landscape levels with a research agenda that untangles complex agricultural landscapes’ contributions to people and nature under current and future conditions.

Aim: The spatial extent (scale) at which landscape attributes are measured has a strong impact on inferred species-landscape relationships. Consequently, researchers commonly measure landscape variables at multiple scales to select one scale (the 'scale of effect') that yields the strongest species-landscape relationship. Scales of effect observed in multiscale studies may not be true scales of effect if scales are arbitrarily selected and/or are too narrow in range. Miscalculation of the scale of effect may explain why the theoretical relationship between scale of effect and species traits, e.g. dispersal distance, is not empirically well supported. Location: World-wide. Methods: Using data from 583 species in 71 studies we conducted a quantitative review of multiscale studies to evaluate whether research has been conducted at the true scale of effect. Results: Multiple lines of evidence indicated that multiscale studies are often conducted at suboptimal scales. We did not find convincing evidence of a relationship between observed scale of effect and any of 29 species traits. Instead, observed scales of effect were strongly positively predicted by the smallest and largest scales evaluated by researchers. Only 29% of studies reported biological reasons for the scales evaluated. Scales tended to be narrow in range (the mean range is 0.9 orders of magnitude) and few (the mean number of scales evaluated is four). Many species (44%) had observed scales of effect equal to the smallest or largest scale evaluated, suggesting a better scale was outside that range. Increasing the range of scales evaluated decreased the proportion of species with scales of effect equal to the smallest or largest scale evaluated. Main conclusions: To ensure that species-landscape relationships are well estimated, we recommend that the scales at which landscape variables are measured range widely, from the size of a single territory to well above the average dispersal distance.

Agricultural systems have been continuously intensified to meet rising demand for agricultural products. However, there are increasing concerns that larger, more connected crop fields and loss of seminatural areas exacerbate pest pressure, but findings to date have been inconclusive. Even less is known about whether increased pest pressure results in measurable effects for farmers, such as increased insecticide use and decreased crop yield. Using extensive spatiotemporal data sampled every 2 to 3 d throughout five growing seasons in 373 cotton fields, we show that pests immigrated earlier and were more likely to occur in larger cotton fields embedded in landscapes with little seminatural area (<10%). Earlier pest immigration resulted in earlier spraying that was further linked to more sprays per season. Importantly, crop yield was the lowest in these intensified landscapes. Our results demonstrate that both environmental conservation and production objectives can be achieved in conventional agriculture by decreasing field sizes and maintaining seminatural vegetation in the surrounding landscapes.

1. Agricultural landscapes are characterised by dynamic crop mosaics changing in composition and configuration over space and time. Although semi-natural habitat has been often shown to contribute to pest biological control, the effects of increasing landscape heterogeneity with cropland have been disregarded. Here, we examine how cereal aphids, their enemies and biological control are affected by the composition and configuration of the crop mosaic and its inter-annual change due to crop rotation. 2. We studied the abundance of cereal aphids, natural enemies and aphid parasitism over 2 years on 51 winter wheat fields. Arthropods were monitored at three distances (0, 10, 30 m) from field borders. Fields were embedded in landscapes of 1-km diameter selected along orthogonal gradients of compositional crop heterogeneity (crop diversity), configurational heterogeneity (field border and grassy field boundary length) and inter-annual change in cover of aphid host habitats (cereal, maize and grassland). We aimed to disentangle spatial and temporal heterogeneity effects through these independent landscape gradients. 3. Aphid densities were lower in landscapes with smaller field size (more field borders) coupled with high amounts of grassy field boundaries. Aphid densities decreased also in landscapes with higher crop diversity when the cover of aphid host habitat had decreased from the year before. Aphid natural enemy densities decreased with smaller field size and high amounts of grassy field boundaries. Aphid parasitism decreased with the inter-annual expansion in aphid host habitat, but only in landscapes with small field sizes. 4. Synthesis and applications. Our study shows for the first time that cereal aphid numbers can be reduced by optimising the composition, configuration and temporal heterogeneity of the crop mosaic. We highlight the value of maintaining small field sizes in agricultural landscapes and high densities of grassy boundaries for reducing aphid abundance. Landscape-wide crop diversification can reduce aphid densities as well.

ContextNitrogen (N) and phosphorus (P) exports from rural landscapes can cause eutrophication of inland and coastal waters. Few studies have investigated the influence of the spatial configuration of nutrient sources—i.e. the spatial arrangement of agricultural fields in headwater catchments—on N and P exports.ObjectivesThis study aimed to (1) assess the influence of the spatial configuration of nutrient sources on nitrate (NO3−) and total phosphorus (TP) exports at the catchment scale, and (2) investigate how relationships between landscape composition (% agricultural land-use) and landscape configuration vary depending on catchment size.MethodsWe analysed NO3− and TP in 19 headwaters (1–14 km², Western France) every two weeks for 17 months. The headwater catchments had similar soil types, climate, and farming systems but differed in landscape composition and spatial configuration. We developed a landscape configuration index (LCI) describing the spatial organisation of nutrient sources as a function of their hydrological distance to streams and flow accumulation zones. We calibrated the LCI’s two parameters to maximise the rank correlation with median concentrations of TP and NO3−.ResultsWe found that landscape composition controlled NO3− exports, whereas landscape configuration controlled TP exports. For a given landscape composition, landscape spatial configuration was highly heterogeneous at small scales (< 10 km2) but became homogeneous at larger scales (> 50 km2).ConclusionsThe spatial configuration of nutrient sources influences TP but not NO3− exports. An ideal placement of mitigation measures to limit diffuse TP export should consider both the hydrological distance to streams and flow accumulation zones.

ContextIntensive agricultural management practices and landscape homogenisation are the main drivers of biodiversity loss in agricultural landscapes. Agricultural fields are regularly disturbed and provide unstable habitats due to crop management regimes. This may lead to movement of arthropods into neighbouring non-arable habitats, as natural and semi-natural habitats provide suitable overwintering sites.ObjectivesHere we assessed the effect of landscape composition and configuration on the overwintering spider and carabid fauna of grassy field margins and hedgerows.MethodsWe sampled ground-dwelling arthropods at field edges of different types (grassy field margin and hedgerows), landscape composition (diverse and simple) and configuration (mosaic and large-scale agricultural landscapes).ResultsWe detected larger spiders in hedgerows than in grassy field margins and in complex landscapes rather than in simple landscapes. We found a significant effect of interaction between landscape composition and edge type on ballooning propensity of spiders. Agrobiont carabids were more abundant in field edges of compositionally simple and large-scale agricultural landscapes. Furthermore, we showed an effect of interaction between landscape composition and edge type on agrobiont spiders. We collected larger carabids in grassy field margins than in hedgerows and carabids were smaller in simple landscapes than in diverse landscapes. The spider community was affected by edge type, and landscape composition had a significant effect on the carabid community.ConclusionsSmall-scale agricultural landscapes may have higher overall densities of ground-dwelling spiders and carabids than large scale landscapes due to the relatively high edge density and the higher quantity of available overwintering sites.

Understanding how landscape structure, the composition and configuration of land use/land cover (LULC) types, affects the relative supply of ecosystem services (ES), is critical to improving landscape management. While there is a long history of studies on landscape composition, the importance of landscape configuration has only recently become apparent. To understand the role of landscape structure in the provision of multiple ES, we must understand how ES respond to different measures of both composition and configuration of LULC. We used a multivariate framework to quantify the role of landscape configuration and composition in the provision of ten ES in 130 municipalities in an agricultural region in Southern Québec. We identified the relative influence of composition and configuration in the provision of these ES using multiple regression, and on bundles of ES using canonical redundancy analysis. We found that both configuration and composition play a role in explaining variation in the supply of ES, but the relative contribution of composition and configuration varies significantly among ES. We also identified three distinct ES bundles (sets of ES that regularly appear together on the landscape) and found that each bundle was associated with a unique area in the landscape, that mapped to a gradient in the composition and configuration of forest and agricultural LULC. These results show that the distribution of ES on the landscape depends upon both the overall composition of LULC types and their configuration on the landscape. As ES become more widely used to steer land use decision-making, quantifying the roles of configuration and composition in the provision of ES bundles can improve landscape management by helping us understand when and where the spatial pattern of land cover is important for multiple services.

Context There is great interest in land management practices for pollinators; however, a quantitative comparison of landscape and local effects on bee communities is necessary to determine if adding small habitat patches can increase bee abundance or species richness. The value of increasing floral abundance at a site is undoubtedly influenced by the phenology and magnitude of floral resources in the landscape, but due to the complexity of measuring landscape-scale resources, these factors have been understudied. Objectives To address this knowledge gap, we quantified the relative importance of local versus landscape scale resources for bee communities, identified the most important metrics of local and landscape quality, and evaluated how these relationships vary with season. Methods We studied season-specific relationships between local and landscape quality and wild-bee communities at 33 sites in the Finger Lakes region of New York, USA. We paired site surveys of wild bees, plants, and soil characteristics with a multi-dimensional assessment of landscape composition, configuration, insecticide toxic load, and a spatio-temporal evaluation of floral resources at local and landscape scales. Results We found that the most relevant spatial scale and landscape factor varied by season. Early-season bee communities responded primarily to landscape resources, including the presence of flowering trees and wetland habitats. In contrast, mid to late-season bee communities were more influenced by local conditions, though bee diversity was negatively impacted when sites were embedded in highly agricultural landscapes. Soil composition had complex impacts on bee communities, and likely reflects effects on plant community flowering. Conclusions Early-season bees can be supported by adding flowering trees and wetlands, while mid to late-season bees can be supported by local addition of summer and fall flowering plants. Sites embedded in landscapes with a greater proportion of natural areas will host a greater bee species diversity.

1. Semi-natural habitats (SNH) provide essential resources for many organisms in agricultural landscapes and can increase biodiversity at the local and landscape scale. For the management of ecosystem services, it is crucial to understand how local characteristics of SNH and the surrounding landscape complexity affect beneficial species. 2. We investigated this for hoverflies (Diptera: Syrphidae)—an important functional group providing both pest control and pollination services—in a total of 138 SNH within 35 agricultural landscapes in Switzerland and Germany. SNH differed in type (woody, herbaceous), shape (areal, linear) and availability of food resources (floral resources and aphids). They were located along a gradient of landscape complexity (1%-75% SNH in a 1 km radius). 3. In total, 9,030 hoverflies belonging to 89 species were collected. In both countries, hoverfly community composition was mainly driven by SNH type and SNH shape, in addition to landscape complexity in Switzerland. Species richness of hoverflies increased with additional SNH at the landscape scale. However, the ubiquitous and dominant aphidophagous species Episyrphus balteatus was indifferent to landscape composition. 4. Species richness of total and aphidophagous hoverflies was higher in woody than in herbaceous SNH. Hoverfly species richness was similar in linear and areal SNH, but non-aphidophagous hoverflies were more vulnerable to landscape simplification in linear than areal SNH. Effects of the SNH type partly differed between the two countries. In Germany, the dominant aphidophagous species E. balteatus preferred woody over herbaceous SNH, while no such difference was found in Switzerland. Overall, local richness and abundance of floral resources were poor predictors for composition. 5. Synthesis and applications. Hoverfly species richness and community composition in semi-natural habitats (SNH) were mainly driven by the SNH type and landscape complexity. Conservation and restoration of complex agricultural landscapes with a high proportion of different SNH types is therefore key for the conservation of hoverfly diversity, and thus likely to promote pest control and pollination services provided by them. Thereby, local improvement of SNH to promote hoverflies has to consider regional differences in habitat characteristics.

ContextBiodiversity in tropical region has declined in the last decades, mainly due to forest conversion into agricultural areas. Consequently, species occupancy in these landscapes is strongly governed by environmental changes acting at multiple spatial scales.ObjectivesWe investigated which environmental predictors best determines the occupancy probability of 68 bird species exhibiting different ecological traits in forest patches.Methods.We conducted point-count bird surveys in 40 forest sites of the Brazilian Atlantic forest. Using six variables related to landscape composition and configuration and local vegetation structure, we predicted the occupancy probability of each species accounting for imperfect detections.ResultsLandscape composition, especially forest cover, best predicted bird occupancy probability. Specifically, most bird species showed greater occupancy probability in sites inserted in more forested landscapes, while some species presented higher occurrence in patches surrounded by low-quality matrices. Conversely, only three species showed greater occupancy in landscapes with higher number of patches and dominated by forest edges. Also, several species exhibited greater occupancy in sites harbouring either larger trees or lower number of understory plants. Of uttermost importance, our study revealed that a minimum of 54% of forest cover is required to ensure high (> 60%) occupancy probability of forest species.ConclusionsWe highlighted that maintaining only 20% of native vegetation in private property according to Brazilian environmental law is insufficient to guarantee a greater occupancy for most bird species. We recommend that policy actions should safeguard existing forest remnants, expand restoration projects, and curb human-induced disturbances to minimise degradation within forest patches.