Stream-Riparian Corridors - Disturbance, Linkages, and Resistance

众所周知，河岸（即溪边）森林限制了溪流中的光照和植物生长，同时提供了为溪流食物网提供燃料的有机物质。这种类型的横向相互作用在陆地和水生系统之间产生了密切的联系。在河流中有同样强大的上游和下游联系。森林采伐通过改变陆地和水生元素之间的联系，对流域景观的山坡和溪流子系统都产生了干扰。河岸过程可能决定了山坡扰动如何影响溪流。在这个项目中，研究人员探讨了河岸植被和河流之间的相互作用如何影响河流对森林砍伐的反应。他们通过对流域的比较研究来关注河岸植被的作用，在这些流域中，采伐将清除上坡植被，但留下不同宽度的河岸带。设计了两个研究元素，1)解决河岸植被如何缓冲对河流的干扰，并组织陆地和河流生态系统之间的横向联系，2)量化在森林采伐后不同宽度的河岸植被保留时的河流梯度或“恢复距离”。响应变量包括河流的物理模板（沉积物、光、热）、有机物动力学（叶片分解）、生物地球化学（营养成分和浓度）和生物成分搜索等方面。该项目将直接与NSF Coweeta LTER项目的成员互动，并进一步发展研究和教育基础设施。最后，研究结果将促进我们对干扰及其影响的理解，将研究与政策制定联系起来，并解决管理者对南部阿巴拉契亚流域的担忧。

Riparian (i.e., stream side) forests are known to restrict light availability and plant growth in streams while providing organic matter that fuels stream food webs. Lateral interactions of this type generate intimate links between terrestrial and aquatic systems. There are equally strong upstream and downstream linkages within streams. By altering the linkages between terrestrial and aquatic elements, forest harvest is a disturbance that influences both hillslope and stream subsystems of watershed landscapes. Riparian processes may dictate how hillslope disturbance influences streams. In this project, the investigators address how interactions between riparian vegetation and streams influence stream responses to forest clear-cutting. They focus on the role of riparian vegetation through comparative studies among watersheds where clear-cutting will remove upslope vegetation but leave riparian zones of differing widths. Two research elements are designed to, 1) address how riparian vegetation buffers disturbance to the stream and organizes lateral linkages between terrestrial and lotic ecosystems, and 2) quantify in-stream gradients or 'recovery distances' when different widths of riparian vegetation remain after forest harvest. Response variables include aspects of the stream's physical template (sediment, light, heat), organic matter dynamics (leaf breakdown), biogeochemistry (nutrient composition and concentration), and biotic composition.search. The project will interact directly with members of the NSF Coweeta LTER program and further development of the research and education infrastructure. Finally, results will advance our understanding of disturbance and its influences, link research and policy formation, and address manager's concerns for southern Appalachian watersheds.