Ecosystem Function in Watershed Meta-Ecosystems

生态系统彼此之间有着内在的联系，小到昆虫从水体中爬出来，死在陆地上，大到撒哈拉沙漠的灰尘吹过大西洋，给亚马逊雨林施肥。元生态系统理论的发展是为了解释生物、资源和能量在生态系统边界之间的流动。通过结合群落生态学（生物的扩散）和生态系统生态学（资源通量），它提供了更好地理解人类所依赖的生态系统功能的机会：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前景尚未在实证和应用环境中实现。造成这种情况的一个原因是，理论工作在很大程度上是空间隐含的，忽视了景观中不同生态系统的配置塑造它们之间联系的方式。我的研究计划的长期目标是开发和使用空间明确的元生态系统方法来理解整个生态系统、流域和景观的功能。目的1。我们将开发空间明确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功能。在元生态系统研究中，觅食和迁徙动物跨生态系统边界的资源移动是一种独特的机制，可以对抗重力和洋流等被动梯度运输资源。我们的建模工作将展示人类对动物种群规模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，如跨溪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，我们将解开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，从而有利于管理。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。它通过揭示栖息地破碎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。该研究计划将产生一个新的建模框架，以理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，如流域及其子集水区。

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.