干旱区生态环境知识资源中心(Arid): 黑河中游荒漠生态系统归一化植被指数对降水的响应

Arid

	黑河中游荒漠生态系统归一化植被指数对降水的响应
其他题名	Changes in normalized difference vegetation index of deserts and dunes with precipitation in the middle Heihe River Basin
	李芳 1; 赵文智2
来源期刊	植物生态学报
ISSN	1005-264X
出版年	2016
卷号	40 期号:12 页码:1245-1256
中文摘要	降水是荒漠生态系统主要的水分来源,是植被结构和功能变化的根本驱动力。该研究以黑河中游砾质荒漠(砾漠)和沙质荒漠(沙漠)为研究对象,基于2000-2012年中分辨率成像光谱仪(MODIS)获取的归一化植被指数(NDVI)数据以及日降水数据,运用多元线性回归法,分析了砾漠和沙漠植被生长季(5-9月)、生长季早期(5-6月)和晚期(7-9月)累积NDVI (NDVI_(INT), INT表示某时间段的累积值)对冷季降水(P_c,前一年9月至当年2月累积降水)、暖季降水(P_w,当年3月至8月累积降水)、前一年生长季NDVI_(INT) (NDVI_(INT-pys))以及干湿气候期(干旱期: 2001-2003;湿润期: 2004-2007年)的响应。研究结果表明: (1)砾漠植被生长季NDVI_(INT)年际变化的影响因素排序为NDVI_(INT-pys) > P_c > P_w,沙漠植被NDVI_(INT)则为P_w > NDVI_(INT-pys);砾漠生长季NDVI_(INT)早期NDVI_(INT)年际变化的影响因素排序为NDVI_(INT-pys) > P_c,晚期则为NDVI_(INT-pys) > P_c = P_w;而沙漠生长季早期NDVI_(INT)年际变化的影响因素为NDVI_(INT-pys),晚期是P_w。(2)在干湿气候期内,降水量并非是影响荒漠NDVI_(INT)变化的关键因子。干湿气候期交替时,砾漠NDVI_(INT)较沙漠增加明显;湿润期内,湿润期持续的长短是影响两种生境植被NDVI_(INT)的关键因子,以沙漠较为明显。黑河中游砾漠和沙漠植被生产力对冷暖季降水及干湿气候期响应具有明显的差异,但总体显示出荒漠植被生产力对降水响应具有滞后性特征。以上结论可为揭示荒漠植被生产力对降水的响应机理提供参考。
英文摘要	Aims Precipitation is the major water source for desert ecosystems, with its temporal dynamics significantly driving the changes of ecosystem structure and function in desert regions. The objectives of this study are to evaluate the changes in normalized difference vegetation index (NDVI) with seasonal precipitation and different climate years in two cover types (desert and dune). Methods Based on the daily rainfall dataset of 2000-2012 in the middle Heihe River Basin in Northwest China and the NDVI extracted from the moderate resolution imaging spectroradiometer (MODIS) images, we performed linear regression analysis to examine the correlation of NDVI_(INT) (accumulated NDVI) with precipitation in two cover types (desert and dune). Two measures of the precipitation are P_c (cool-season precipitation from last September to late February) and P_w (warm-season precipitation in between March and August), while NDVI was characterized with NDVI_(INT-pys) (previous-year during the different climate years (dry: 2001-2003, wet: 2004-2007)) and the different periods of a growing season (i.e. whole growing season from May through September, early growing season in between May and June, and late growing season in between July and September). Important findings We found that: (1) the determinants of growing season NDVI_(INT) and their order were NDVI_(INT)- pys > P_c > P_w for the deserts, while the order was P_w > NDVI_(INT-pys) for the dunes. The determinants and their order of NDVI_(INT) in early growing season were NDVI_(INT-pys) > P_c for the desert, while they were NDVI_(INT-pys) > P_c = P_w for the late growing season. However, for the dunes, NDVI_(INT) of the early and late growing season appeared determined by NDVI_(INT-pys) and P_w, respectively. (2) During the dry and wet periods, precipitation was not a significant factor influencing NDVI_(INT) for the desert and dune. However, significant increases in NDVI_(INT) were observed at dune under wet condition. With the wet years continued, the length of the wet years become an important determinant of NDVI_(INT) at both cove types, particularly at dune. In addition, it appeared that different changes in NDVI with precipitation existed between the two cover types, but with very similar effects of time-lag. These findings provide useful references for further understanding the mechanisms of NDVI changes with precipitation.
中文关键词	累积归一化植被指数(NDVI_(INT)) ; 冷季降水 ; 暖季降水 ; 干湿气候期 ; 滞后性 ; 生态水文
英文关键词	accumulated normalized difference vegetation index (NDVI_(INT)) precipitation of cold season precipitation of warm season dry and wet climate period lag time ecohydrology
语种	中文
国家	中国
收录类别	CSCD
WOS类目	PLANT SCIENCES
WOS研究方向	Plant Sciences
CSCD记录号	CSCD:5886999
来源机构	中国农业科学院草原研究所
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/235308
作者单位	1.中国农业科学院草原研究所, 呼和浩特, 内蒙古 010010, 中国; 2.中国科学院西北生态环境资源研究院,中国生态系统研究网络临泽内陆河流域研究站, 兰州, 甘肃 730000, 中国
推荐引用方式 GB/T 7714	李芳,赵文智. 黑河中游荒漠生态系统归一化植被指数对降水的响应[J]. 中国农业科学院草原研究所,2016,40(12):1245-1256.
APA	李芳,&赵文智.(2016).黑河中游荒漠生态系统归一化植被指数对降水的响应.植物生态学报,40(12),1245-1256.
MLA	李芳,et al."黑河中游荒漠生态系统归一化植被指数对降水的响应".植物生态学报 40.12(2016):1245-1256.