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Agriculture is the main driver of the rapid collapse of biodiversity, upon which all life on Earth, including agricultural production, depends. As we face the challenge of feeding a growing human population under a changing climate regime, the pressure on biodiversity is expected to further intensify. While the potential to expand and improve natural habitats for biodiversity conservation has been widely explored in large-scale scenarios of agricultural systems, the critical role of agricultural landscapes’ management on halting the loss of biodiversity remains unexplored at this scale. We argue that, to achieve an effective conservation of biodiversity (both natural and agricultural), the combined multivariate effects of agriculture on biodiversity must be accounted for, including its surface area as well as its management. Based on a literature review, we identified the main biodiversity pressures stemming from agriculture: land-use change, contribution to climate change, water withdrawal, pesticide pollution, nutrient (nitrogen and phosphorus) pollution, and landscape and farmscale simplification (of croplands and pastures). For each one, we proposed a critical boundary, based on reviews of studies covering a range of taxa, biodiversity metrics, and biomes, below or above which negative impacts on biodiversity are minimized or positive effects arise. Implemented simultaneously, the identified boundaries would integrate biodiversity conservation within and across farmlands and minimize agriculture’s far-reaching impacts on biodiversity. We present a framework called “agricultural boundaries for biodiversity” that will allow to explore the potential of developing agricultural systems that effectively reconcile food production and biodiversity conservation at large scales. [ABSTRACT FROM AUTHOR]

The plot-level decisions of land managers (i.e., farmers, ranchers, and forest owners) influence landscape-scale environmental outcomes for biodiversity in agricultural landscapes. The impacts of their decisions often develop in complex, non-additive ways that unfold over time and space. Behavioral science offers insights into ways decision-makers manage complexity, uncertainty, choice over time, and social influence. We review such insights to understand the plot-level conservation actions of farmers that impact biodiversity. To make these connections concrete, we provide a case study of the decision to adopt biodiversity management practices in the heavily cultivated region of the Central Valley, California, USA. We use results from a survey of 122 farmers in the region to test whether adoption is related to farm tenure arrangements or peer influence. We find farmers who are more sensitive to peer influence are three times more likely to adopt practices that support biodiversity, including wildflowers, native grasses, cover crops, hedgerows, and wetlands. This relationship could have important implications for how plot-level decisions aggregate to landscape-scale outcomes. Finally, we suggest priorities for future research and program design to integrate behavioral science into biodiversity conservation in agricultural landscapes. By considering land managers' plot-level conservation decisions with the lens of behavioral science, we identify barriers and opportunities to promote environmental benefits. [ABSTRACT FROM AUTHOR]

Assessing how much management of agricultural landscapes, in addition to protected areas, can offset biodiversity erosion in the tropics is a central issue for conservation that still requires cross‐taxonomic and landscape‐scale studies. We measured the effects of Amazonia deforestation and subsequent land‐use intensification in 6 agricultural areas (landscape scale), where we sampled plants and 4 animal groups (birds, earthworms, fruit flies, and moths). We assessed land‐use intensification with a synthetic index based on landscape metrics (total area and relative percentages of land uses, edge density, mean patch density and diversity, and fractal structures at 5 dates from 1990 to 2007). Species richness decreased consistently as agricultural intensification increased despite slight differences in the responses of sampled groups. Globally, in moderately deforested landscapes species richness was relatively stable, and there was a clear threshold in biodiversity loss midway along the intensification gradient, mainly linked to a drop in forest cover and quality. Our results suggest anthropogenic landscapes with high‐quality forest covering >40 % of the surface area may prevent biodiversity loss in Amazonia. Article impact statement: Tropical landscapes should retain over 40% of forests and 50% of unaffected patches to efficiently conserve biodiversity. [ABSTRACT FROM AUTHOR]

Agricultural intensification has substantially reduced multi-scale habitat heterogeneity, including increased field size and loss of semi-natural structures, thus resulting in large-scale deterioration of farmland biodiversity. Biodiversity conservation in farmland has therefore become a conservation priority on a regional as well as continental scale. The effect of habitat heterogeneity on biodiversity on different trophic and niche levels is poorly understood, particularly in agricultural regions with simple arable patterns, where biodiversity has declined most conspicuously. To investigate the effects of habitat heterogeneity on biodiversity in an intensively managed arable-dominated agricultural landscape, we measured the abundance and species richness of spiders, butterflies, birds and European hares as well as the fine-scale habitat composition on various spatial scales. Additionally, we examined correlations between species richness and abundance among taxonomic groups to investigate if any of the biodiversity parameters provided a good indicator of overall farmland biodiversity. We found that smaller patch sizes and larger areas of non-cropped elements (margins, hedges and grasslands) were related to higher farmland biodiversity of different taxonomic groups but habitat diversity was not. The positive effect of these factors was recorded on both spatial scales and in a separate analysis considering groups with different habitat requirements and dispersal abilities. Biodiversity parameters (i.e. species richness and abundance) of the taxonomic groups were positively correlated with one another. In particular, butterfly species richness correlated with bird, butterfly and spider abundance and with bird species richness, suggesting that it may be a good indicator of general farmland biodiversity in intensively managed arable landscapes. Our results suggest that enhancing the heterogeneity of farmed landscapes by decreasing field size and increasing the availability of non-cropped habitats may be a valuable tool for conserving farmland biodiversity in intensive arable farmlands. [ABSTRACT FROM AUTHOR]

Mediterranean central Chile is globally recognized as a hotspot for terrestrial biodiversity due to its high endemism and massive habitat loss. However, within the rural landscape of central Chile, significant extents of natural areas remain, especially on less productive, steep slopes, and vegetation strips extending from the surrounding hills to agricultural areas. Accordingly, vegetation strips or corridors, within lowland farms, constitute key elements to support the conservation of biodiversity in rural landscapes. To assess the ecological performance of corridors in 22 commercials vineyards in central Chile, we characterized them in terms of width-, length-, area-, and perimeter-to-area ratios, as well as the number of connections with natural areas. Based on a set of previously defined ecological indicators (species, functional groups, and structural components), we compared their occurrence in corridors within vineyards and in the surrounding natural areas. We evaluated the effects of corridor attributes on the occurrence of the selected ecological indicators, using a generalized linear mixed model with each vineyard as a random factor. The area, width, and length of vegetation corridors varied widely (1.2–86.3 ha, 10.5–95 m, and 380–5000 m, respectively). We found significant differences in the occurrence of indicators between corridors and natural areas. All sampled ecological indicators in corridors showed a negative relationship with the distance to the nearest natural area. Vegetation strips within vineyards represent important opportunities for biodiversity conservation that significantly enhance habitat quality in the agricultural landscape for biodiversity and habitat connectivity. [ABSTRACT FROM AUTHOR]