2000—2020年岷江上游干旱河谷区植被时空变化及其地形效应  

Spatial and Temporal Changes of Vegetations and Its Topographic Effects on the Arid Valley Area of the Upper Reaches of Minjiang River from 2000 to 2020

作　　者：周雪妮 肖成志 刘磊[1] 计扬 曹亚廷 李小红 巴仁基[1] ZHOU Xueni;XIAO Chengzhi;LIU Lei;JI Yang;CAO Yating;LI Xiaohong;BA Renji(Civil-Military Integration Center of China Geological Survey,Chengdu,Sichuan 610036,China;Key Laboratory of Natural Resource Coupling Process and Effects,Beijing 100055,China;College of Environment and Civil Engineering,Chengdu University of Technology,Chengdu,Sichuan 610059,China;School of Geophysics&Geomatics,China University of Geosciences(Wuhan),Wuhan,Hubei 430074,China)

机构地区：[1]中国地质调查局军民融合地质调查中心,四川成都610036 [2]自然资源要素耦合过程与效应重点实验室,北京100055 [3]成都理工大学环境与土木工程学院,四川成都610059 [4]中国地质大学(武汉)地球物理与空间信息学院,湖北武汉430074

出　　处：《现代地质》2024年第3期589-598,共10页Geoscience

基　　金：中国地质调查局军民融合地质调查中心项目(DD20220955,DD20220881)。

摘　　要：针对岷江上游干旱河谷区生态极其脆弱的特点,利用NDVI数据通过像元二分法反演了岷江上游干旱河谷区2000—2020年的植被覆盖度(FVC),运用线性趋势分析和F显著性检验法,定量分析了FVC的时空变化规律,结合地形数据剖析岷江上游干旱河谷区FVC趋势变化与海拔、坡度、坡向之间的关系。结果表明:(1)2000—2020年,研究区植被覆盖度呈波动增加趋势,年均FVC由2000年0.62增加至2020年的0.67。(2)在空间上,植被覆盖度由低海拔至高海拔呈现增高趋势,低等级和中低等级植被覆盖度主要分布在岷江干流及岷江支流杂谷脑河两岸,中等级和中高等级植被覆盖度集中分布在河谷两岸低中山和中山区,高等级植被覆盖度则主要分布在远离河谷的高中山和中高山区。(3)高等级植被覆盖面积随海拔增加呈先减小后增加的趋势,在1100~1400 m和3200~3500 m区域达到峰值;高等级植被覆盖度面积随坡度增加呈现先增加后减少的趋势,10°~20°和30°~40°是植被覆盖度高等级和中高-高等级的峰值区;总体上阳坡植被覆盖度高于阴坡。植被覆盖状况受海拔、坡度以及坡向影响较大,对岷江上游干旱河谷区生态保护应考虑地形影响,因地制宜采取措施。Considering the extremely fragile ecological characteristics in the arid valley area of Upper Reaches of Minjiang River(URMR),we inverted the Fractional Vegetation Cover(FVC)of the arid valley area of URMR from 2000 to 2020,using the NDVI data and the approach of image element dichotomy.We further qua.pngied the spatial and temporal variations of the FVC index using the linear analysis and F significance test.The relationship between FVC and altitude,slope,and aspect were analyzed in the arid valley area of URMR.The results showed that(1)the FVC index showed a fluctuating increasing trend from 2000 to 2020,and the annual average FVC increased from 0.62 in 2000 to 0.67 in 2020.(2)Spatially,FVC showed an increasing trend from the low altitude area to the high altitude one.FVC in the low and medium-low-grade was mainly distributed on the banks of the main stream and tributaries of the Minjiang River,while FVC in the medium and medium-high grade was distributed on both banks of Minjiang River,and FVC in the medium and medium-high grade was distributed in the URMR valley.FVC in the medium and high grade was distributed in the low and medium altitude mountains on both sides of the river valley,and FVC in the high grade was mainly distributed in the high and medium altitude mountains away from the river valley.(3)The area with a high vegetation coverage decreases and then increases with the increasing altitude,and the high vegetation coverage reaches to its peak in the altitude of 1,100-1,400 m and 3,200-3,500 m.The area with a high vegetation coverage increases with the slope,while the area with a high vegetation coverage shows an increasing and then decreasing trend with the increasing slope gradients.The areas with slopes of 10°-20°and 30°-40°were the peak of high and medium-high to high vegetation coverage.Overall,the vegetation coverage on the sunny slope was higher than that on shady side,and FVC index is greatly affected by the factors of altitude,slope,and aspect.Therefore,the effects of topography and local

关 键 词：植被覆盖度 时空变化 地形效应 岷江上游 干旱河谷 

分 类 号：P931[天文地球—自然地理学] Q948[生物学—植物学]