青藏铁路沿线NDVI的人类活动和气候变化响应

The response of NDVI along the Qinghai-Tibet railway to human activities and climate change

针对青藏铁路建设和运营对青藏高原植被生态的影响程度以及归一化植被指数(NDVI)和气候因子之间的响应关系,该文选用MODIS NDVI遥感数据,利用最大值合成法进行趋势分析、相关性分析、变异系数分析。结果表明:①青藏铁路在修建和运营期间对沿线植被生态的影响主要集中在5km范围内,影响程度与距铁路距离成反比;②青藏铁路沿线降水对植被覆盖的影响较气温密切;③青藏铁路的工程建设对周边植被有显著影响,核心区植被覆盖变化更为显著;④青藏铁路工程整体对周边生态的扰动以中等和较低波动为主。

Aiming at the impact of the construction and operation of Qinghai-Tibet railway on the vegetation ecology of Qinghai-Tibet Plateau and the response relationship between normalized difference vegetation index(NDVI)and climatic factors,the maximum value composite method was used for trend analysis,correlation analysis and variation coefficient analysis based on moderate-resolution imaging spectroradiometer(MODIS)NDVI remote sensing data.The results showed that the impact of Qinghai-Tibet railway on the vegetation ecology along the line during the construction and operation period was mainly concentrated within 5km,and the degree of impact was inversely proportional to the distance from the railway;the impact of precipitation along Qinghai-Tibet railway on vegetation coverage was closer than that of temperature;the construction of Qinghai-Tibet railway had a significant impact on the surrounding vegetation,and the vegetation coverage changes in the core area were more significant;the overall disturbance of Qinghai-Tibet railway project to the surrounding ecology was mainly moderate and low fluctuations.