辽宁省植被覆盖度时空演变及其对气候因子的响应

基于MODIS-NDVI数据及像元二分模型，对辽宁省植被覆盖度进行估算，并在此基础上探讨了辽宁植被覆盖度时空演变特征及其对气候因子的响应，结果表明：2000-2018年辽宁省植被覆盖度整体呈波动增加趋势，年平均增长速率为0.38%，呈增加趋势的面积占总面积的92.3%；2000年以来，裸地及低覆盖区域占比逐年减小，中低覆盖、中覆盖及高覆盖区域占比分别增加11.35%、11.00%和9.22%；辽宁省植被覆盖度与气候因子的关系表现出明显的空间差异性，其中，西部易旱地区覆盖度与气温呈显著负相关，与降水呈正相关，东部地区覆盖度与气温呈正相关，与降水呈负相关；辽宁植被覆盖度对降水的响应存在一个月的滞后期，对气温的响应无滞后效应。

Spatio-temporal evolution of vegetation coverage and its responses to climatic factors in Liaoning province

Based on the estimated vegetation coverage (VC) in Liaoning province using MODIS-NDVI data and mixed pixel decomposition model, the spatio-temporal evolution of VC and its responses to climatic factors were investigated.The results show that the VC experiences a fluctuating increasing trend with an average annual rate of 0.38% from 2000 to 2018.The region with increasing trend accounts for 92.3% of the vegetated area.The bare land and low-coverage area decrease year by year, and the percentages of the middle-low, middle and high coverage areas increase by 11.35%, 11.00% and 9.22%, respectively, since 2000.The relationships between the VC and climatic factors show significant spatial variability.Specifically, the VC in the west of Liaoning which is drought prone region is negatively correlated with temperature and positively correlated with precipitation.However, the VC in the east of Liaoning has positive and negative relationships with temperature and precipitation, respectively.Besides, the VC has a lag response of one month to the precipitation, but not to the temperature in Liaoning province.