摘要
植被是联系陆地、大气和生态系统的自然纽带,其随着气候和人类活动而发生变化,因此,研究它的突变和变化趋势具有重要意义。本文利用3年滑动t检验、Mann-Kendall检验(MK检验)和距平分析法,研究了中国1982-2006年5-9月平均的NDVI(NOAA/AVHRR GIMMS)突变和变化趋势及其主要原因。3年滑动t检验和MK检验表明,1998年华东地区的NDVI出现了突变,而东北地区和青藏高原NDVI没有出现突变。NDVI变化趋势的分析表明,1982-1998年华东地区NDVI为较平稳的趋势,1998年出现突变后,1998-2006年转为明显下降的趋势(以1998年为转折点)。因此,华东地区NDVI存在明显的变化趋势。NDVI突变和变化趋势的成因分析表明,20世纪90年代后期至21世纪初,随着华东地区大规模的城市化建设和房地产的过度开发,导致耕地面积减少,华东地区植被1998年出现了突变,并从偏多转为明显偏少的趋势,而卫星仪器和气候因子并非是导致该地植被出现突变和变化趋势的主要原因。
Vegetation is an important part of the terrestrial ecosystem, and it is the natural bond for linking land,atmosphere and ecosphere. Vegetation changes with climate and human activity, thus, studying its sudden and trend changes is an important subject. Using the methods of 3-year moving t-test, Mann-Kendall test(MK-test)and anomaly analysis, the sudden and trend changes of the normalized difference vegetation index(NDVI of AVHRR GIMMS) in China from May to September during 1982 to 2006, as well as their causes were analyzed.The t-test and MK-test results show that there was a sudden change of NDVI in the eastern China in 1998, and there couldn’t be a sudden change of NDVI in the northeast China and the Tibetan Plateau during 1982 to 2006.The changing trend of NDVI indicates that there was an increasing trend during 1982 to 1998, and then a decreasing trend from 1999 to 2006 in the eastern China. The causes of the sudden and trend changes of NDVI reveal that with the massive urbanization process in China that started in the late 1990 s, the city and built- ups increased and the arable area decreased, and the NDVI indicated a sudden change with the vegetation decreased in the eastern China. Moreover, the satellite instruments and climate factors couldn’t be the main causes of the decreasing vegetation in the eastern China.
出处
《地球信息科学学报》
CSCD
北大核心
2015年第11期1333-1340,共8页
Journal of Geo-information Science
基金
卫星遥感全球下垫面类型数据集(GYHY201106014)
公益性行业(气象)科研专项经费项目"青藏高原遥感积雪气候数据集建设(GYHY201206040)"
关键词
NDVI
突变
成因
NDVI
sudden change
causes