应用Landsat影像数据分析岷江上游植被覆盖度时空变化及地形分异特征  

Temporal and Spatial Variation of Vegetation Coverage and Its Topographical Differentiation in the Upstream of Minjiang River with Landsat Remote Sensing Image

作　　者：黄兰鹰 杨育林[1] 高鹏 严欣荣 尤继勇[4] 张好[4] 贺维[4] 吴雨峰[4] Huang Lanying;Yang Yulin;Gao Peng;Yan Xinrong;You Jiyong;Zhang Hao;He Wei;Wu Yufeng(Ecological Restoration and Conservation on Forest and Wetland Key Laboratory of Sichuan Province,Sichuan Academy of Forest,Chengdu 610081,P.R.China;Litang County Forestry and Grassland Bureau;Institute of Geographic Science and Natural Resources Research,CAS;Ecological Restoration and Conservation on Forest and Wetland Key Laboratory of Sichuan Province,Sichuan Academy of Forest)

机构地区：[1]森林和湿地生态恢复与保育四川省重点实验室(四川省林业科学研究院),成都610081 [2]理塘县林业和草原局 [3]中国科学院地理科学与资源研究所 [4]森林和湿地生态恢复与保育四川省重点实验室(四川省林业科学研究院)

出　　处：《东北林业大学学报》2023年第1期54-60,共7页Journal of Northeast Forestry University

基　　金：四川省重点实验室项目(2022ZDSY01);四川省科技计划项目(2019ZHFP0094)。

摘　　要：以2000、2010和2020年的Landsat遥感影像为数据源,利用像元二分模型提取岷江上游3个时期的植被覆盖度,结合海拔、坡度以及坡向等地形因子,对研究区2000—2020年的植被覆盖状况变化及地形分异特征进行分析,为生态保护和土地规划利用提供数据支持。结果表明:(1)2000—2020年,研究区植被覆盖度呈先降低后升高的趋势,总体上得到改善,植被覆盖度Ⅲ级以上区域面积达到80%以上。(2)植被覆盖度在空间上呈现为“东高西低,南高北低”的分布特征,岷江上游中西部地区的植被覆盖度为Ⅳ级以上,黑水县西北部山区和松潘县的极高海拔地带植被覆盖度为Ⅰ级。(3)随海拔、坡度的上升,研究区植被覆盖度均表现为先升高后降低的特征;植被覆盖度半阳坡最大,阴坡最小,平地大于半阴坡。岷江上游作为长江上游的生态屏障,植被覆盖状况受海拔、坡度以及坡向和人类活动影响较大,因此,对岷江上游地区生态保护和土地利用应考虑地形限制,因地制宜采取措施。With three periods of remote sensing images of Landsat(2000,2010 and 2020),the dimidiate pixel model was used to calculate vegetation coverage in three periods in the upstream of the Minjiang River and topographic differentiation characteristics were analyzed in combination with altitude,slope and slope aspect.The temporal and spatial variation of vegetation cover and its topographical differentiation in the study area were analyzed to provide data support for its ecological protection and land planning and utilization.The results showed:(1)During 2000-2020,the vegetation coverage in the study area showed a trend of decreasing and then increasing,the overall improvement.More than 80%of the area was dominated with medium coverage or above.(2)The overall spatial distribution pattern of vegetation coverage was“high east and low west,high south and low north”.The med-high vegetation coverage was mainly distributed in the central and western parts of the upstream of the Minjiang River,while the low vegetation coverage was mainly distributed in the northwestern mountainous area of Heishui County and the extremely high altitude area of Songpan County.(3)The vegetation coverage in the study area increased and then decreased with the rise of altitude and slope.The vegetation coverage in the study area showed the characteristic from small to large with the change of slope aspect.And the vegetation coverage of the semi sunny slope was the largest,the flat land was larger than the semi shady slope,and the shady slope was the smallest.The upstream of the Minjiang River serve as an ecological barrier for the upstream of the Yangtze River and other rivers,the vegetation coverage in the study area was greatly affected by altitude,slope and slope aspect,and human activities.Ecological protection and land use should be taken into account in the terrain constraints according to local conditions.

关 键 词：Landsat影像 像元二分模型 植被覆盖度 时空变化 地形分异 

分 类 号：S757[农业科学—森林经理学]