云南省九大高原湖泊流域NDVI时空演变及其与气候的响应关系

(1.云南师范大学 旅游与地理科学学院, 昆明 650500; 2.云南省基础地理信息中心, 昆明 650034)

NDVI; 九大高原湖泊流域; 偏相关分析; 变化轨迹分析

Temporal and Spatial Evolution of NDVI and Its Response Relation with the Climate in the Nine Plateau Lake Basins of Yunnan Province
LI Yingxin1, LI Shihua2, PENG Shuangyun1

(1.College of Tourism and Geographic Sciences, Yunnan Normal University, Kunming 650500, China; 2.Yunnan Provincial Geomatics Centre, Kunming 650034, China)

NDVI; nine plateau lake basins; partial correlation analysis; change trajectory analysis

备注

探究云南省九大高原湖泊流域NDVI的时空演变及其与气候的响应关系,对云南省九大高原湖泊流域的生态环境保护及生态安全建设具有重要意义。以2000年、2005年、2010年、2015年4个时段的Landsat数据及同期的气象数据为数据源,应用趋势分析、偏相关分析、变化轨迹等方法,研究近16 a云南省九大高原湖泊流域NDVI时空演化情况及其与气候因子的响应关系。结果 表明:(1)近16 a来,九大高原湖泊流域NDVI总体以0.026/10 a的速率上升,但各流域的NDVI变化差异显著。星云湖、杞麓湖流域植被退化面积较大,而抚仙湖流域植被恢复效果明显。(2)九大高原湖泊流域NDVI变化与气候因子均有一定的相关性(程海流域除外),但相关性不显著,且不同区域空间异质性明显,滇西、滇西北地区的流域气温与NDVI值的相关性大于降水与NDVI值的相关性; 滇中地区的流域降水与NDVI值的相关性大于气温与NDVI值的相关性; 滇南地区的流域NDVI值与气温和降水相关性差异不大; 位于金沙江河谷地区的程海流域NDVI值与气温和降水呈负相关;(3)NDVI变化与高程分异相关性显著,植被垂直分布明显,1 000~3 000 m的高程带内,NDVI值随高程的增加而增加,3 000m是九大高原湖泊流域NDVI值的转折点。(4)非植被类型转化为植被类型是九大高原湖流域NDVI时空转换的主要形式,而滇池流域由裸土转化为水体或建筑的数量较多。

Exploring the spatiotemporal evolution of NDVI and its response to climate in the nine plateau lake basins in Yunnan Province is of great significance to the ecological environment protection and ecological security construction. Based on the Landsat data of 2000, 2005, 2010 and 2015 and the meteorological data in the same period, the spatiotemporal evolution of NDVI in nine plateau lake basins in Yunnan Province in recent 16 years and its response to climate factors were studied by using methods such as trend analysis, partial correlation analysis and change trajectory. The results show that:(1)in the past 16 years, the NDVI of the nine plateau lake basins has generally increased at a rate of 0.026/decade, but there are significant differences in NDVI changes among the basins; the Xingyun Lake and Qilu Lake basins have a large area of vegetation degradation, while Fuxian Lake basin has obvious effects of vegetation restoration;(2)except Chenghai basin, NDVI changes in nine plateau lake basins have certain correlation with climatic factors, but the correlation is not significant, and the spatial heterogeneity in different regions is obvious; the correlation between temperature and NDVI values in the basins in western and northwest Yunnan is greater than that between precipitation and NDVI values; the correlation between precipitation and NDVI values in the basins of central Yunnan is greater than that between temperature and NDVI values; the correlation between NDVI values and temperature and precipitation in the basins of southern Yunnan is not significant; NDVI values in Chenghai basin which is located in Jinsha River valley is negatively correlated with temperature and precipitation;(3)NDVI changes are significantly correlated with elevation differentiation, and the vertical distribution of vegetation is obvious; in the elevation band of 1 000~3 000 m, NDVI values increase with the increase of elevation, and 3 000 m is the turning point of NDVI values in nine plateau lake basins;(4)the transformation from non-vegetation type to vegetation type is the main form of NDVI spatiotemporal transformation in the nine plateau lake basins, while the transformation from bare soil to water area or building area in Dianchi lake basin is relatively significant.