基于Landsat8的2015年贵州省农业干旱监测研究

Study on Agricultural Drought Monitoring in Guizhou Province in 2015 Based on Landsat8

在全球气候变暖背景下,干旱普遍发生,而农业干旱对国民经济发展的影响尤为明显,威胁着国家的粮食安全和生态安全。基于贵州省2015年不同季节的landsat8 OIL遥感数据,利用影像数据所获取的植被覆盖指数和地表温度数据,拟合植被指数(NDVI)和地表温度(LST)的特征空间,设计得到贵州省2015年春、夏、秋、冬4个不同季节的不同土壤湿度,将TVDI作为监测农业干旱状况的指标,得到贵州省2015年的农业干旱时空分布图。结果表明,土壤含水率的高低与植被覆盖和地表温度有关,且TVDI更适宜中等植被覆盖的土壤湿度反演。贵州省2015年全年旱情较缓,各地区均不存在春旱或伏旱,只有冬季绝大部分地区土壤含水率较低,更有力地促进了农业干旱的发生。因此,对农业干旱的监测研究可为贵州省农业干旱的监测管理提供依据,对今后减少农业干旱的影响和进一步促进农业社会经济可持续发展具有重要的现实意义。

Under the background of global warming,drought generally occurs,and the impact of agricultural drought on national economic development is particularly obvious.At the same time,agricultural drought also threatens the national food security and ecological security.Based on the remote sensing data of Landsat8 OIL in different seasons of Guizhou Province in 2015,using the vegetation coverage index(NDVI) and surface temperature(LST) data obtained from the image data,fitting the characteristic space of vegetation index(NDVI)and surface temperature(LST),the different soil moisture in spring,summer,autumn and winter of Guizhou Province in 2015 was designed,and TVDI was taken as the index of monitoring agricultural drought spatial and temporal distribution of agricultural drought in Guizhou Province in 2015.The results showed that the soil moisture content was related to vegetation cover and surface temperature,and TVDI was more suitable for soil moisture inversion of medium vegetation cover.In 2015,the drought in Guizhou Province was relatively slow,and there was no spring drought or summer drought in all areas.Only in winter,the soil moisture content in most areas was low,which promoted the occurrence of agricultural drought more effectively.Therefore,the study of agricultural drought monitoring provides a basis for the monitoring and management of agricultural drought in Guizhou Province,and has important practical significance for reducing the impact of agricultural drought and further promoting the sustainable development of agricultural social economy in the future.