PRF/M: A Geographical Information System Analysis of Stream Detrital Processing

Coweeta实验森林(美国农业部林业局运营的一个地点)的四条溪流向下游移动木质垃圾的速度将进行比较。然后，这些结果将与来自波多黎各卢基洛实验森林的一对溪流的类似结果进行比较。在重大降雨事件发生后，将绘制添加到这些支流源头的标记(标记)木材的位置图，以确定这些木块的数量和大小如何影响其向下游移动。在蜿蜒穿过老森林的溪流中，预计木材的数量和大小会更多地导致泥石坝的形成，从而降低水流速度，增加树叶在溪流中的滞留，从而改变溪流的物理化学条件。这种差异对底栖动物群落成员的种类组成和丰富度有着深远的影响。这项研究的一个主要组成部分是应用地理信息系统(地理信息系统)技术记录天然和添加的木质碎屑位置的顺序变化。正在开发的一些地理信息系统软件将用于通过使用地形、高程和坡度的数字数据来模拟天然集水区下游的物质移动。开发这一方法是为了处理从遥感(飞机和卫星)图像获得的数字化数据。存储和处理大型比较数据集的能力在生态学研究中得到了广泛的应用，但尚未应用于碎屑物质的分析。俄克拉荷马大学的艾伦·P·科维奇博士将为这项研究投入12个月的环境生物学终身教职。主办机构是佐治亚大学。

Rates of woody debris movement downstream will be compared among four streams in Coweeta Experimental Forest (a site operated by the U.S. Department of Agriculture's Forest Service). These will then be compared with analogous results from a pair of streams in Puerto Rigo's Luquillo Experimental Forest. The locations of marked (tagged) wood added to headwaters of these tributary streams are to be mapped after major rainfall events in order to determine how quantity and sizes of these pieces influence their downstream movement. The greater amont and diversity of sizes of wood expected in streams meandering through older forests will more often lead to formation of debris dams, which decrease water flow rates and increase retention of leaf litter within the stream, thereby altering physico-chemical conditions of the stream. Such differences have a profound influence on the species composition and abundances of benthic community members. A major component of this study is the application of Geographical Information System (GIS) technology to record sequential changes in positions of natural and added woody debris. Some of the GIS software being developed will be used to simulate movement of materials downstream in natural catchment basins by using digital data on topography, elevation, and slope. This methodology has been developed to manipulate digitized data available from remotely sensed (aircraft and satellite) imagery. The capacity to store and handle large comparative data sets is finding wide use in ecological studies but has not yet been applied to analysis of detrital materials. Dr. Alan P. Covich, of the University of Oklahoma, will devote twelve months of Mid- Career Fellowship in Environmental Biology tenure to this research. The host institution is the University of Georgia.