2000-2014年黄河流域区域尺度植被结构时空分异特征分析  

Spatio -temporal Change Analysis of Vegetation Structural Characteristics of Yellow River Basin during 2000 - 2014 based on MODIS Products

作　　者：胡必波 王志慧[2] 武婕 鲍宏喆[2] 倪用鑫 杨二[2] WU Jie1,2, WANG Zhihui 2 , DONG Zengchuan1(1. College of hydrology and water resources, HoHai university , Nanjing 210098;2. Yellow River Institute of Hydraulic Research, Yellow River Conservancy Commission, Zhengzhou 45000)

机构地区：[1]四川省自贡市水利电力建筑勘测设计院 [2]黄河水利委员会黄河水利科学研究院 [3]河海大学水文水资源学院

出　　处：《名城绘》2018年第4期277-282,207,共7页

摘　　要：植被结构是影响植被水土保持效应的重要因素之一,遥感技术是监测区域尺度植被结构动态变化的最有效工具.本文将植被叶面积指数分解为植被覆盖度与垂直维叶面积指数2个参数指标,分别表示植被的水平维结构和垂直维结构.本文利用2000-2014年的MOD44B和MOD15A2H产品,基于Mann-Kendall趋势检验与Sen斜率分析方法,由大空间尺度到像素尺度,分析黄河流域、黄河源区、黄土高原以及黄河各子流域和不同坡度上的植被水平维与垂直维结构的时空分异特征.结果表明：（1）2000-2014年黄河流域植被覆盖度变化趋势不显著,而垂直维LAI呈显著上升趋势.在大空间尺度上,树木覆盖度与垂直维LAI呈显著正相关关系,黄土高原退耕还林还草工程对植被垂直维结构的影响大于对植被水平维结构的影响.（2）黄土高原植被结构参数增加面积比重大,河源区变化面积比重小.黄土高原植被垂直维结构相对变化率最大.（3）黄河源区5°以下区域植被结构变化面积比和相对变化率最大,黄土高原15°-25°区域内的变化面积比重最大.植被结构参数的相对变化率呈现随坡度的增加而逐渐降低的趋势.Vegetation structural characteristic is an important factor determining soil and water conservation effect of vegetation. Remote sensing technology is the most effective tool to monitor vege-tation dynamics at regional scale. In this paper, the spatio-temporal variation characteristics of vegetation structure in the horizontal and vertical dimensions including fractional vegetation coverage （ F V C ）, tree coverage and leaf area index （ LAI） in the vertical dimension were analyzed from large regional scale to MO D I S pixel scale using Mann-IKendall trend test and Sen’ s slope analysis methods based on MOD 44B and MOD 15A 2 H products during 20 0 0 to 2014. The re-sults show that 1） The variation trend of FVC is not significant, and vertical-dimension LAI have significant increasing trend. Tree cover is positively and significantly related to LAI in the vertical dimension at large spatial scale. 2） The proportion of areas where vegetation structural parameters increase significantly is highest in the loess plateau, and lowest in the source region. Relative change ratio of vertical-dimension LAI in the loess plateau is largest. 3） The ratio of changed area and relative change ratio of vegetation structural parameters within the area with slope less than 5. in the source region is highest. The ratio of change area of vegetation structural parameters within the area with slope between 15. and 2 5. in the loess plateau is highest. It is also observed that variation density of vegetation structural parameters will decrease with slope increase.

关 键 词：MODIS产品 植被覆盖度 垂直维LAI 树木覆盖度 时空分异规律 

分 类 号：S157.1[农业科学—土壤学]