Ecosystem Function in Watershed Meta-Ecosystems

流域元生态系统中的生态系统功能

• 批准号: RGPIN-2021-03778
• 负责人: Little, Chelsea
• 金额: $ 2.04万
• 依托单位: Simon Fraser University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2021
• 资助国家: 加拿大
• 起止时间: 2021-01-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=742714
• 关键词: Ecosystem; Function; Watershed; Meta; Ecosystems

Ecosystems are intrinsically connected to each other, through movements as small as insects emerging from waterbodies to die on land, to those as distant as dust from the Sahara blowing across the Atlantic Ocean to fertilize the Amazon rainforest. Meta-ecosystem theory was developed to account for flows of organisms, resources, and energy across ecosystem boundaries. By combining community ecology (the dispersal of organisms) and ecosystem ecology (resource fluxes), it presents the opportunity to better understand the functioning of ecosystems that humans rely on: how important are they, and can changes in the functioning of one ecosystem have cascading effects across a landscape because of these connections? Unfortunately, the promise of meta-ecosystem ecology has not yet been fulfilled in empirical and applied settings. One reason for this is that theoretical work has largely been spatially implicit, neglecting the ways that the configuration of different ecosystems in a landscape shape the connections between them. The long-term goal of my research program is to develop and use spatially-explicit meta-ecosystem approaches for understanding the functioning of whole ecosystems, watersheds, and landscapes. Objective 1. We will develop spatially-explicit theoretical models to examine how animal movement influences ecosystem function by redistributing resources. While largely unaddressed in meta-ecosystem research so far, the movement of resources across ecosystem boundaries by foraging and migratory animals is a unique mechanism transporting resources against passive gradients such as gravity and currents. Our modeling work will show how human impacts on animal population sizes and habitat connectivity could affect resource flows, landscape heterogeneity, and ecosystem function. Objective 2. My research group will explore how the spatial configuration of watersheds can be used to predict ecosystem functions such as respiration and decomposition across stream and river networks. We will draw on classic theories of watershed structure, such as the River Continuum Concept, and use new geostatistical methods to model spatial covariance in decomposition and ecosystem respiration. We will thus disentangle the roles of network structure and terrestrial land cover on these key ecosystem functions. Our research will benefit management by developing new ways to estimate the functioning of entire watersheds. My proposed research will accelerate meta-ecosystem ecology by identifying how landscape and watershed structure mediates ecosystem function. It has direct relevance for the management by revealing how habitat fragmentation and other human impacts may alter animal contributions to the functioning of ecosystems. This research program will produce a new modeling framework to understand and predict ecosystem function at scales that are relevant for human interaction and management, such as watersheds and their subcatchments.

生态系统从本质上是相互联系的，从从水体中冒出的昆虫到陆地上死亡的昆虫，到从撒哈拉沙漠吹来的尘埃吹过大西洋肥沃亚马逊雨林的那些小生物。元生态系统理论的发展是为了解释生物、资源和能量跨越生态系统边界的流动。通过将群落生态学(生物体的扩散)和生态系统生态学(资源通量)结合起来，它为更好地理解人类所依赖的生态系统的功能提供了机会：它们有多重要，一个生态系统功能的变化是否会因为这些联系而在整个景观中产生级联效应？不幸的是，元生态系统生态学的承诺尚未在经验和应用环境中实现。其中一个原因是，理论工作在很大程度上是空间上的隐含，忽略了景观中不同生态系统的配置如何塑造它们之间的联系。我的研究计划的长期目标是开发和使用空间显式的元生态系统方法，以了解整个生态系统、流域和景观的功能。目标1.我们将开发空间显式的理论模型来研究动物运动如何通过重新分配资源来影响生态系统的功能。虽然到目前为止，元生态系统研究基本上没有涉及到这一问题，但通过觅食和迁徙动物跨越生态系统边界的资源转移是一种独特的机制，可以对抗重力和洋流等被动梯度来运输资源。我们的建模工作将展示人类对动物种群大小和栖息地连通性的影响如何影响资源流动、景观异质性和生态系统功能。目标2.我的研究小组将探索如何利用流域的空间配置来预测生态系统功能，如跨河流和河流网络的呼吸和分解。我们将借鉴经典的流域结构理论，如河流连续体概念，并使用新的地统计学方法来模拟分解和生态系统呼吸的空间协方差。因此，我们将理清网络结构和陆地覆盖对这些关键生态系统功能的作用。我们的研究将通过开发新的方法来评估整个流域的功能，从而使管理受益。我提出的研究将通过确定景观和流域结构如何调节生态系统功能来加速元生态系统生态学。它通过揭示栖息地碎片化和其他人类影响如何改变动物对生态系统功能的贡献，与管理直接相关。这项研究计划将产生一个新的建模框架，以了解和预测与人类互动和管理相关的尺度上的生态系统功能，如流域及其子流域。