Abrupt downstream forest decline following river damming in southern Alberta
Abrupt downstream forest decline following river damming in southern Alberta
复制标题
艾伯塔省南部河流筑坝导致下游森林急剧减少
作者：
S. Rood;Sig Heinze
通过比较阿尔伯塔省南部有水坝的圣玛丽河和沃特顿河与邻近无水坝的贝利河的森林丰度，研究了筑坝对河岸白杨林丰度的影响。通过1961年和1981年拍摄的航空照片估算森林的线性河流距离，确定了大坝上游和下游的森林分布。在20年的间隔中，圣玛丽大坝下游的水量减少了48%，该大坝于1951年建成。1964年完工的沃特顿大坝下游，河岸森林减少了23%。在研究期间，无坝贝利河下游地区的杨树丰度相对没有变化，减少了不到1%。在20年的时间间隔内，这三条河流的上游（无水坝）部分的森林都略有减少；圣玛丽河、贝利河和沃特顿河沿岸分别下降了4.7%、4.6%和6.1%。因此，南方两条河的筑坝…
The influence of river damming on the abundance of riparian poplar forests was investigated by comparing forest abundances on the dammed St. Mary and Waterton rivers of southern Alberta with the neighbouring undammed Belly River. Forest distributions were determined by estimating the linear river distance of forests from airphotos taken in 1961 and 1981, both upstream and downstream from the dams. During the 20-year interval, a 48% reduction occurred downstream from the St. Mary Dam, which was completed in 1951. Downstream from the Waterton Dam, completed in 1964, riparian forests declined 23 %. Poplar abundance along the downstream region of the undammed Belly River was relatively unchanged over the study period, showing less than a 1 % reduction. The upstream (undammed) portions of all three rivers underwent a slight forest decline during the 20-year interval; declines of 4.7, 4.6, and 6.1 % occurred along the St. Mary, Belly, and Waterton rivers, respectively. Thus, the damming of two rivers in souther...