中国农业气象 ›› 2018, Vol. 39 ›› Issue (12): 814-824.doi: 10.3969/j.issn.1000-6362.2018.12.006

• 论文 • 上一篇    

玛纳斯河流域植被覆盖度随地形因子的变化特征

位宏,徐丽萍,李晓蕾,薛凯   

  1. 1.石河子大学理学院,石河子 832003;2.南京师范大学地理科学学院,南京 210023;3.虚拟地理环境教育部重点实验室,南京 210023
  • 出版日期:2018-12-20 发布日期:2018-12-11
  • 作者简介:位宏(1992?),硕士生,主要从事GIS应用、景观格局研究。E-mail:hnwh12012@163.com
  • 基金资助:

    新疆维吾尔自治区研究生科研创新项目(XJGRI2017044);国家自然科学基金项目(31760151)

Variation Characteristics of Vegetation Coverage Based on Terrain Factors in the Manas River Basin

WEI Hong, XU Li-ping, LI Xiao-lei, XUE Kai   

  1. 1.College of Science, Shihezi University, Shihezi 832003, China; 2.School of Geography Science, Nanjing Normal University, Nanjing, 210023; 3. Key Laboratory of Virtual Geographical Environment, Nanjing 210023
  • Online:2018-12-20 Published:2018-12-11

摘要:

基于2000-2016年MODIS NDVI数据,利用像元二分模型和ArcGIS空间分析功能对玛纳斯河流域植被覆盖度分布格局及动态变化特征进行研究,并分析植被覆盖度变化在高程、坡度和坡向上的空间分布差异。结果表明:(1)玛纳斯河流域以低等级植被覆盖为主,高等级植被覆盖面积显著增加,其它各等级面积波动较小,研究期内植被覆盖改善的面积比例(31.17%)远大于退化的面积比例(16.1%),研究区总体植被覆盖度增加,生态环境有所好转。(2)在海拔<800m,坡度<8°区域内,植被覆盖度明显改善,植被显著退化区主要分布在海拔1300-3400m,坡度>25°区域内,植被覆盖度未发生变化的区域主要集中在海拔>3600m范围内。(3)当海拔>2100m时,植被覆盖度随海拔增加呈现持续减少的趋势,海拔低于2100m的地带,植被覆盖度随海拔增加波动较大。(4)随着坡度的增加,植被覆盖度呈逐渐减小的趋势,全流域0?5°坡度范围内植被覆盖度最大(42.69%)。(5)在各坡向上,植被覆盖度差异不明显。流域内平地上的植被覆盖度最大(44.21%);阴坡的植被覆盖度优于阳坡,植被变化趋势除在平地区域较显著外,其余坡向间差异不大。

关键词: 植被覆盖度, 地形因子, 像元二分模型, 玛纳斯河流域

Abstract:

Based on MODIS NDVI data from 2000 to 2016, the distribution pattern and dynamic change characteristics of vegetation coverage in the Manas River Basin of Xinjiang were studied by using the dimidiate pixel model and the spatial analysis of ArcGIS, and the spatial distribution differences of vegetation cover change in elevation, slope and aspect were analyzed. The results showed that: (1) the Manas River Basin was dominated by low vegetation cover, the area of high-level vegetation coverage was significantly increased, and the other levels were less volatile. The area ratio of vegetation cover improvement (31.17%) was much larger than the proportion of degraded area (16.1%) during the study period, the overall vegetation coverage of the study area increased, and the ecological environment improved. (2)In the area of elevation <800m and slope <8°, the vegetation coverage was obviously improved. The vegetation significantly degraded areas were mainly distributed in the elevation of 1300-3400m, the slope was >25°, and the area where the vegetation coverage had not changed was mainly concentrated in the elevation > 3600m. (3)When the elevation was >2100m, the vegetation coverage tended to decrease with the increase of elevation. In the area below 2100m, the vegetation coverage fluctuated greatly with the increase of elevation. (4)With the increase of slope, the vegetation coverage gradually decreased. The vegetation coverage was the largest (42.69%) in the 0?5 degree slope of the whole basin. (5)The difference of vegetation coverage was not significant in all aspects. The vegetation coverage on the flat ground was the largest (44.21%), and the vegetation coverage on the shade aspect was better than the sunny aspect. There was no obvious difference of the vegetation coverage change except in the flat ground.

Key words: Vegetation coverage, Topography factor, Dimidiate pixel model, Manas River Basin