Liu Zhiyong, Li Chao, Zhou Ping, Chen Xiuzhi
Institute of Geography, Heidelberg University, Heidelberg 69120, Germany.
Department of Global Ecology, Carnegie Institution for Science, Stanford, California, USA.
Sci Rep. 2016 Oct 7;6:35105. doi: 10.1038/srep35105.
Climate change significantly impacts the vegetation growth and terrestrial ecosystems. Using satellite remote sensing observations, here we focus on investigating vegetation dynamics and the likelihood of vegetation-related drought under varying climate conditions across China. We first compare temporal trends of Normalized Difference Vegetation Index (NDVI) and climatic variables over China. We find that in fact there is no significant change in vegetation over the cold regions where warming is significant. Then, we propose a joint probability model to estimate the likelihood of vegetation-related drought conditioned on different precipitation/temperature scenarios in growing season across China. To the best of our knowledge, this study is the first to examine the vegetation-related drought risk over China from a perspective based on joint probability. Our results demonstrate risk patterns of vegetation-related drought under both low and high precipitation/temperature conditions. We further identify the variations in vegetation-related drought risk under different climate conditions and the sensitivity of drought risk to climate variability. These findings provide insights for decision makers to evaluate drought risk and vegetation-related develop drought mitigation strategies over China in a warming world. The proposed methodology also has a great potential to be applied for vegetation-related drought risk assessment in other regions worldwide.
气候变化对植被生长和陆地生态系统有重大影响。利用卫星遥感观测数据，我们在此聚焦于研究中国不同气候条件下的植被动态以及与植被相关的干旱可能性。我们首先比较了中国归一化植被指数（NDVI）和气候变量的时间趋势。我们发现，在变暖显著的寒冷地区，植被实际上没有显著变化。然后，我们提出了一个联合概率模型，以估计在中国生长季不同降水/温度情景下与植被相关的干旱可能性。据我们所知，本研究首次从联合概率的角度审视了中国与植被相关的干旱风险。我们的结果展示了在低降水/温度条件和高降水/温度条件下与植被相关的干旱风险模式。我们进一步确定了不同气候条件下与植被相关的干旱风险变化以及干旱风险对气候变异性的敏感性。这些发现为决策者评估干旱风险以及在全球变暖背景下制定中国与植被相关的干旱缓解策略提供了见解。所提出的方法在全球其他地区进行与植被相关的干旱风险评估方面也具有很大的应用潜力。
