摘要
基于MOD16产品,利用作物缺水指数法,结合气象站点观测资料及MOD17植被指数信息,分析了2000—2013年陕西关中地区干旱的时空分布特征。结果表明：基于MOD16产品的作物缺水指数的计算结果与站点土壤相对湿度的变化规律一致,并且两者的相关系数通过了P〈0.001的显著性检验,说明MOD16数据可以用于关中地区干旱的时空变化分析;作物缺水指数的空间分布不均匀,在关中地区的东部和北部值较高,较为干旱,特别是在关中东北部和西安市周边干旱特别严重,作物缺水指数多年平均值在0.795-0.832,达到重旱等级,并且区域内干旱程度呈显著上升趋势;作物缺水指数有明显的年内变化波动,在3—6月及10—11月值最高,作物缺水指数达0.7左右,其中3—6月是重旱和特旱集中发生的时期,而10—11月以轻旱和中旱为主;2000—2013年作物缺水指数在2003年出现最低值（0.65左右）,后逐年升高,在2013年达最高值（0.8左右）;2000—2013年轻旱面积呈减小的趋势,中、特旱呈增加趋势;作物缺水指数与温度、降水及植被的关系密切,高温少雨时,作物缺水指数偏高,干旱容易发生,同时归一化植被指数较低。
Based on MOD16 products and the method of crop water stress index, combined with meteorological station observations and MOD17 vegetation index information, this article analyzed the Spatial-temporal variation characteristics of drought in the Guanzhongregion of Shaanxi Province during 2000-2013. The results showed that crop water stress index based on MOD16 products was consistent with the variation of soil relative humidity, and the correlation coefficient between them was significant （ P 〈 0. 001 ）. This relationship indicated that MOD16 products could be used to analyze the variation features in Guanzhong region. In addition, the crop water stress index had not been evenly distributed. In eastern and northern of Guanzhong regions, its value was high, suggesting relatively dry condition. Particularly, in the northeast of Guanzhong region and around Xi＇ an city, the crop water stress index was 0. 795 - 0. 832, reaching a heavy drought level. In the meantime, drought severity was becoming elevated. Furthermore, the crop water stress index had obvious monthly fluctuation variations, reaching its highest value of 0. 7 in March to June and October to November. From March to June, heavy and severe drought events mainly occurred. Rather from October to November, light and medium drought events mostly took place. In Guanzhong region, the crop water stress index exhibited an increasing trend, after minimum and maximum values of 0.65 in 2003 and 0.8 in 2013, respectively. The area suffered light drought showed a trend of becoming reduced. However, areas with medium to severe drought were increased during 2000-2013. Moreover, temperature, precipitation and vegetation were closely related to crop water stress index. During the period with higher temperature and less precipitation, the crop water stress index was high, drought was likely to happen, and the normalized difference vegetation index was low.
出处
《干旱地区农业研究》
CSCD
北大核心
2016年第1期236-241,共6页
Agricultural Research in the Arid Areas
基金
陕西省气象局科技创新基金计划项目(2014M-14)
