Center for Remote Sensing of Land Surfaces (ZFL), University of Bonn, Genscherallee 3, 53113, Bonn, Germany.
Remote Sensing Research Group (RSRG), Department of Geography, University of Bonn, Meckenheimer Allee 166, 53115, Bonn, Germany.
Environ Monit Assess. 2019 Jul 24;191(8):510. doi: 10.1007/s10661-019-7620-z.
Droughts have significant negative impacts on livelihoods and economy of Kazakhstan. In this study, we assessed and characterized drought hazard events in Kazakhstan using satellite Remote Sensing time series for the period between 2000 and 2016. First, we calculated Vegetation Condition Index (VCI) and Standardized Enhanced Vegetation Index anomalies (Z) based on 250 m Moderate Resolution Imaging Spectroradiometer (MODIS) Enhanced Vegetation Index (EVI) time series. Second, we assessed vegetation cover changes for the observation period. Third, we analyzed different characteristics of the drought hazard as well as spatial distribution of the drought-affected areas within the country. The results confirmed that drought was one of the environmental challenges for Kazakhstan in 2000-2016. The obtained maps showed that drought hazard conditions were observed every year, though the areal coverage of the drought conditions largely varied between the analyzed years. The calculated drought indices indicated that in years 2000, 2008, 2010, 2011, 2012, and 2014, more than 50% of the area of the country were affected by drought conditions of different severity with the largest droughts in terms of the areal spread occurring in 2012 and 2014. We concluded that the pre-requisite of successful implementation of drought hazard and risk mitigation strategies is availability of spatially explicit, timely, and reliable information on drought hazard. This suggests the necessity of incorporation of remote sensing-based drought information, as was demonstrated in this paper, in the national drought monitoring system of Kazakhstan.
干旱对哈萨克斯坦的生计和经济造成了重大的负面影响。在这项研究中，我们使用卫星遥感时间序列评估和描述了 2000 年至 2016 年期间哈萨克斯坦的干旱灾害事件。首先，我们根据 250m 分辨率中分辨率成像光谱仪（MODIS）增强植被指数（EVI）时间序列计算了植被状况指数（VCI）和标准化增强植被指数异常（Z）。其次，我们评估了观测期间的植被覆盖变化。第三，我们分析了干旱灾害的不同特征以及该国受干旱影响地区的空间分布。结果证实，干旱是 2000-2016 年期间哈萨克斯坦面临的环境挑战之一。得到的地图表明，干旱灾害状况每年都存在，尽管分析年份之间的干旱状况的面积覆盖范围差异很大。计算出的干旱指数表明，在 2000 年、2008 年、2010 年、2011 年、2012 年和 2014 年，该国超过 50%的地区受到不同严重程度的干旱条件影响，而面积最大的干旱发生在 2012 年和 2014 年。我们得出的结论是，成功实施干旱灾害和风险缓解策略的前提是获得关于干旱灾害的空间明确、及时和可靠的信息。这表明有必要将基于遥感的干旱信息纳入哈萨克斯坦国家干旱监测系统，正如本文所展示的那样。
