Agricultural landscape intensification has enabled food production to meet growing demand. However, there are concerns that more simplified cropland with lower crop diversity, less noncrop habitat, and larger fields results in increased use of pesticides due to a lack of natural pest control and more homogeneous crop resources. Here, we use data on crop production and insecticide use from over 100,000 field-level observations from Kern County, California, encompassing the years 2005-2013 to test if crop diversity, field size, and cropland extent affect insecticide use in practice. Overall, we find that higher crop diversity does reduce insecticide use, but the relationship is strongly influenced by the differences in crop types between diverse and less diverse landscapes. Further, we find insecticide use increases with increasing field size. The effect of cropland extent is distance-dependent, with nearby cropland decreasing insecticide use, whereas cropland further away increases insecticide use. This refined spatial perspective provides unique understanding of how different components of landscape simplification influence insecticide use over space and for different crops. Our results indicate that neither the traditionally conceived "simplified" nor "complex" agricultural landscape is most beneficial to reducing insecticide inputs; reality is far more complex.pesticides | biological control | landscape simplification | landscape complexity | crop diversity

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Reducing the costs from human–wildlife conflict, mostly borne by marginal rural households, is a priority for conservation. We estimate the mean species-specific cost for households suffering damages from one of 15 major species of wildlife in India. Our data are from a survey of 5,196 households living near 11 wildlife reserves in India, and self-reported annual costs include crop and livestock losses and human casualties (injuries and death). By employing conservative estimates from the literature on the value of a statistical life (VSL), we find that costs from human casualties overwhelm crop and livestock damages for all species associated with fatalities. Farmers experiencing a negative interaction with an elephant over the last year incur damages on average that are 600 and 900 times those incurred by farmers with negative interactions with the next most costly herbivores: the pig and the nilgai. Similarly, farmers experiencing a negative interaction with a tiger over the last year incur damage that is on average 3 times that inflicted by a leopard and 100 times that from a wolf. These cost differences are largely driven by differences in the incidence of human death and casualties. Our estimate of costs fluctuates across reserves, mostly due to a variation of human casualties. Understanding the drivers of human casualties and reducing their incidence are crucial to reducing the costs from human–wildlife conflict.Most of the tales were about animals, for the Jungle was always at their door. The deer and the pig grubbed up their crops, and now and again the tiger carried off a man at twilight, within sight of the village gates. “Tiger! Tiger!” (Rudyard Kipling, The Jungle Book, Collins Classics, 2010)

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Small-scale farming provides both food and livelihoods for the vast majority of the global poor. Thus, increasing and stabilizing farm incomes and food production in developing countries is fundamental to reducing global poverty. Policies for rural development such as improved access to non-agricultural incomes or land titling may benefit farmers, but they may also lead to farm consolidation with unintended consequences for aggregate food supply. Using a large panel dataset of rural households in Uganda, we parse apart how farm size affects the level and riskiness of agricultural incomes as well as of local food supply. Our findings indicate that while output per unit of land does decline with increasing farm size as suggested by previous literature, agricultural incomes increase with farm size. We show further that while the variance of agricultural incomes declines with increasing farm size, the variance of local food production increases with farm size. These results suggest that farmers benefit from larger farms, earning higher and more stable incomes while consumers suffer from lower and more volatile food supply.

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Agriculture is a major threat to global biodiversity. A common claim is that large-scale agro-industrial farming is mainly responsible for the biodiversity decline, while smaller family farms are more wildlife friendly. Here we leverage a natural experiment along the former inner German border to estimate the causal impact of farm size on biodiversity. We combine land cover data with bird diversity data to establish the mechanisms through which farm size affects bird diversity. Our main results show that the increase in farm size at the former inner German border reduces bird diversity by 15%. The results suggest further that the decline is the result of land cover simplification rather than land use intensification.

Rural households in developing countries depend on crops, forest extraction and other income sources for their livelihoods, but these livelihood contributions are sensitive to climate change. Combining socioeconomic data from about 8,000 smallholder households across the tropics with gridded precipitation and temperature data, we find that households have the highest crop income at 21°C temperature and 2,000 mm precipitation. Forest incomes increase on both sides of this agricultural maximum. We further find indications that crop income declines in response to weather shocks while forest income increases, suggesting that households may cope by reallocating inputs from agriculture to forests. Forest production may thus be less sensitive than crop production to climatic fluctuations, gaining comparative advantage in extreme climates and under weather anomalies. This suggests that well-managed forests might help poor rural households to cope with and adapt to future climate change.