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Global cropland expansion over the last century caused widespread habitat loss and degradation. Establishment of protected areas aims to counteract the loss of habitats and to slow species extinctions. However, many protected areas also include high levels of habitat disturbance and conversion for uses such as cropland. Understanding where and why this occurs may realign conservation priorities and inform protected area policy in light of competing priorities such as food security. Here, we use our global synthesis cropland dataset to quantify cropland in protected areas globally and assess their relationship to conservation aims and socio-environmental context. We estimate that cropland occupies 1.4 million km²or 6% of global protected area. Cropland occurs across all protected area management types, with 22% occurring in strictly protected areas. Cropland inside protected areas is more prevalent in countries with higher population density, lower income inequality, and with higher agricultural suitability of protected lands. While this phenomenon is dominant in midnorthern latitudes, areas of cropland in protected areas of the tropics and subtropics may present greater trade-offs due to higher levels of both biodiversity and food insecurity. Although area-based targets are prominent in biodiversity goal-setting, our results show that they can mask persistent anthropogenic land uses detrimental to native ecosystem conservation. To ensure the long-term efficacy of protected areas, post-2020 goal setting must link aims for biodiversity and human health and improve monitoring of conservation outcomes in cropland-impacted protected areas.

Trees shape the critical zone and modulate terrestrial water storage yet observed streamflow responses to forest cover change vary. Differences in catchment area, soil water storage, management practices, tree species, and climate are among the many explanations proposed for heterogeneous hydrologic responses. We addressed evidence for the hypothesis that mean annual temperature (MAT) and the phase shift between precipitation and enhanced vegetation index (EVI) peaks,θ, explain a significant amount of the variation in hydrologic response to forest cover loss. We selected 50 catchments with daily streamflow records spanning eight nations and seven climate regions. Categorical clustering of catchments was performed with MAT, θ, minimum EVI, catchment area, and percentage forest loss. Similar storm event runoff ratio responses to deforestation were best clustered by MAT andθ. High MAT tropical monsoonal catchments (Brazil, Myanmar, and Liberia) exhibited minimal evidence of increasing runoff ratios (increases observed in 9% of catchments). Low MAT subarctic, cold semi-arid, and humid continental catchments (US, Canada, and Estonia) showed consistent runoff increases around the time of snowmelt (94%). The deforestation runoff responses of temperate and subtropical catchments with Mediterranean, humid, and oceanic climates depended strongly onθ. We observe increased runoff following forest loss in a majority of catchments (90%) where precipitation peaks followed peak growing season (max EVI) (US). In contrast, where precipitation peaks preceded the growing season (South Africa and Australia) there was less evidence of increased runoff (25% of catchments). This research supports the strategic implementation of native forest conservation or restoration for simultaneously mitigating the effects of global climate change and regional or local surface runoff.