干旱区生态环境知识资源中心(Arid): 三江源地区基于净初级生产力的草地生态系统脆弱性特征

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	三江源地区基于净初级生产力的草地生态系统脆弱性特征
其他题名	Vulnerability of Grassland Ecosystems in the Sanjiangyuan Region Based on NPP
	肖桐; 王军邦; 陈卓奇
来源期刊	资源科学
ISSN	1007-7588
出版年	2010
卷号	32 期号:2 页码:323-330
中文摘要	三江源区作为青藏高原的一部分,在目前日益加剧的全球变暖和人类活动现状下,其内部的草地生态系统发生了明显的退化现象,这种退化过程极大的影响了下游地区的生态安全.本文从生态系统最基本的净初级生产力(NPP)出发,利用IPCC提供的生态系统脆弱性的概念,建立了三江源地区基于NPP的脆弱性空间分布格局,同时对其进行了脆弱性等级划分,发现脆弱度等级随平均高程的增加而增高,根据插值得到的降雨量和湿润指数的空间分布,发现中度以上脆弱度主要分布在500mm等降雨量线以西,重度以上脆弱度主要分布在400mm等降雨量线以西,极度脆弱区主要分布在350mm等降雨量线以西.可见该区的脆弱度与降雨量有很大关系.湿润指数-30等值线很好的标示了大部分中度以上脆弱度,因此可见在这一区域水热交互作用是影响植物生长的更重要的因子.
英文摘要	As a part of the Qinghai-Tibet Plateau, the grassland ecosystems in the Sanjiangyuan Region (the source regions of the Yangtze River, Yellow River, and Lancang River) is suffering an obvious eco-environmental degradation, which would greatly impact the downstream areas. Quantitative assessment of ecosystem vulnerability is critical for a better understanding of the functions and processes of ecosystems. In this present study, the authors utilized the concepts and approaches suggested by the Intergovernmental Panel on Climate Change (IPCC) to simulate spatial patterns of vulnerability in grassland ecosystems. NPP was employed to describe the ecosystem vulnerability and the concepts of adaptation and sensitivity were introduced to quantify the changes in ecosystems. If the adaptation is greater than the sensitivity, which represents a kind of characteristic sensitive to external environment changes, the ecosystem is deemed stable, vice versa. Spatial distribution of the vulnerability was derived based on NPP. The authors categorized it as four degrees, i.e., slight vulnerability, moderate vulnerability, severe vulnerability and extreme vulnerability. Through comparing the spatial distribution of the vulnerability with that of precipitation and moisture index, characteristic contours describing the vulnerability were derived. At last, it was concluded that the vulnerability across the areas exhibits an explicit trend from the west to the east. The slight vulnerability and moderate vulnerability were estimated to account for nearly 90% of the entire region, with showing larger contribution of the moderate vulnerability. The slight and moderate vulnerability are primarily distributed in the middle and eastern parts having better hydrothermal conditions. A line through Zaduo, Zhiduo, Qumalai and Chengduo counties was clearly presented and extracted to differentiate the moderate vulnerability from the slight vulnerability. The vulnerability areas in all counties and degradation districts were investigated. In this region, desertification is a major driving force responsible for severe and extreme vulnerability. In the eastern part of the Sanjiangyuan Region, there exists a moderate vulnerability portion influenced by intensive human activities, which is located in Xinghai and Tongde where there are significant changes in land use. With increases in elevation, the vulnerability increases across the region because of lower temperature and less precipitation over the high-elevation areas. Through comparing the derived vulnerability with precipitation, it was found that contours of 500 mm, 400 mm and 350 mm can generally differentiate slight, moderate, severe and extreme degrees of vulnerability. Compared vulnerability with moisture index, when the moisture index was less than 30, it can differentiate the slight vulnerability and other degrees well. Alpine grassland ecosystems dominate the study region. Alpine meadow ecosystems show slight vulnerability and moderate vulnerability whereas the alpine steppe shows the moderate vulnerability.
中文关键词	脆弱性 ; 三江源 ; 草地生态系统
英文关键词	NPP Vulnerability Sanjiangyuan Region Grassland ecosystems NPP
语种	中文
国家	中国
收录类别	CSCD
WOS类目	ENVIRONMENTAL SCIENCES
WOS研究方向	Environmental Sciences & Ecology
CSCD记录号	CSCD:3844599
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/226103
作者单位	中国科学院,地理科学与资源研究所, 北京 100101, 中国
推荐引用方式 GB/T 7714	肖桐,王军邦,陈卓奇. 三江源地区基于净初级生产力的草地生态系统脆弱性特征[J],2010,32(2):323-330.
APA	肖桐,王军邦,&陈卓奇.(2010).三江源地区基于净初级生产力的草地生态系统脆弱性特征.资源科学,32(2),323-330.
MLA	肖桐,et al."三江源地区基于净初级生产力的草地生态系统脆弱性特征".资源科学 32.2(2010):323-330.