Understanding resilience in agroecosystems: landscapes in transition

粮食、纤维和生物燃料生产是土壤提供的核心生态系统服务之一。然而，土壤也有助于水净化、碳固存、生物多样性栖息地和养分循环。促进农业集约化是为日益增长的全球人口增加粮食生产的必要条件。然而，这种加剧也与广泛宣传的围绕水质和水量、温室气体排放和生物多样性减少的环境问题有关。强化带来的最重要问题之一是对变化的适应能力降低。不幸的是，我们没有足够的信息来描述关键土壤生态系统服务对变化的弹性，特别是在加拿大的农业生态系统中。这种信息的缺乏是可持续农业的主要障碍：在全球气候变化下，土壤如何应对集约化导致的土地利用变化，或温度和降水模式的变化？特别是，在整个农业景观中，土壤功能的净变化可能是什么？为了量化土壤在农业生态系统中的恢复力，我们首先需要量化土壤在不同土地利用、不同景观位置下提供的基线生态系统服务。哪些服务可以很容易地量化？在不同的土地用途下，哪些是不同的？哪些不是？通过将土壤性质和功能的敏感测量与土地利用和地形联系起来，我们能否确定在未来变化下，哪些指数对土地利用变化最脆弱（最不具弹性）？最终，我们能否确定一种短期土壤测试来测试长期弹性？反过来，我们能否确定土壤生态系统服务的收益和成本，从而量化农业景观的复原力和可持续性？在这个项目中，我们将研究一套新的跨生态和土地利用梯度的土壤变化指数来回答这些问题。此外，通过观察地形梯度上的这些指数，我们将确定这些丘陵景观中的不同位置如何对变化做出反应。

Food, fiber, and biofuel production is one of the core ecosystem services provided by soils. However, soils also contribute to water purification, carbon sequestration, habitat for biodiversity, and nutrient cycling. Intensification of agriculture is being promoted as essential to increase food production for a growing global population. However, intensification has also been linked to widely publicized environmental issues surrounding water quality and quantity, greenhouse gas emissions, and reduced biodiversity. Among the most significant problems with intensification is reduced resiliency to change. Unfortunately, we do not have sufficient information to characterize the resiliency of key soil ecosystem services to change, particularly in Canadian agro-ecosystems. This lack of information presents a major obstacle to sustainable agriculture: How might soils respond to either a change in land use due to intensification, or to a change in temperature and precipitation patterns under global climate change? In particular, what might the net change in soil function be across the agricultural landscape?To quantify soil's resilience in agro-ecosystems, we first need to quantify the baseline ecosystem services that soils provide under different land uses in different landscape positions. What services can be readily quantified? Which ones differ under different land uses? Which ones do not? By linking sensitive measurements of soil properties and function to land use and landform, can we determine which indices are most vulnerable (least resilient) to land use change under future change? Ultimately, can we identify a short-term soil test for long-term resilience? In turn, can we determine the benefits and costs of soil ecosystem services to quantify resilience and sustainability of agricultural landscapes?In this project, we will look at a suite of novel indices of soil change across ecotonal and land use gradients to answer these questions. Furthermore, by looking at these indices across topographic gradient, we will determine how different positions in these hummocky landscapes might respond to change.