张淑杰1*,张玉书1,陈鹏狮2,梁淑娥3,刘东明2,米娜1,纪瑞鹏1,王阳2,王笑影1,李广霞4
ZHANG Shu-jie1*, ZHANG Yu-shu1, CHEN Peng-shi2, LIANG Shu-e3, LIU Dong-ming2, MI Na1, JI Rui-peng1, WANG Yang2, WANG Xiao-ying1, LI Guang-xia4#br#
摘要： 干旱的发生是一个累积渐进的过程，其对农作物的影响机理非常复杂，准确识别干旱的发生发展演变过程并做出动态定量评估非常重要。本文从作物、气象、土壤三个方面综合考虑，优化和改进了作物水分亏缺指数模型中供需水项的计算方法，实现了从出苗开始逐日模拟玉米的水分亏缺状况，进而能够动态定量描述玉米干旱发生发展致灾演变过程。基于辽宁地区1981—2018年气象、玉米发育期、土壤水分和产量数据，利用改进后的作物水分亏缺指数（CWDIwp）结合春季、秋季、春夏季典型干旱年代表站点减产率与干旱强度的关系，确定了持续时间和CWDIwp的双因子干旱致灾动态阈值指标，在此基础上对辽宁地区典型时段干旱致灾过程进行评估。结果表明：CWDIwp与土壤相对湿度呈显著负相关，与改进前相比，CWDIwp能够更精确地识别干旱的起止时间、干旱历时和干旱程度，更准确地刻画干旱的发生、发展、持续、缓解和解除的演变过程。区域应用显示，该方法可以逐日滚动评估干旱的发生发展，且与实际发生情况一致性较好，不同程度干旱面积对比误差约为9%。
Abstract: The occurrence of drought is a cumulative and gradual process. The mechanism underlying the effects of drought on crops is complicated. It is important to accurately and quantitatively identify and evaluate the occurrence and development of drought. In this study, the crop water deficit index model was improved by optimizing the calculation method of water supply and demand, with the influences of soil, crops and meteorological conditions being considered. The simulation of daily water deficit for maize beginning from emergence was achieved, realizing the dynamic and quantitative description of droughtinduced disaster process of maize. Using the data of meteorological condition, development period of maize, soil moisture and yield during 1981-2018 in Liaoning, based on crop water deficit index(CWDIwp) and relationship between yield reduction rate and drought intensity at representative sites in typical years with spring, autumn, springtosummer droughts, twofactor (i.e., duration and CWDIwp) dynamic threshold index of droughtinduced disaster was determined. Then, the disastercausing processes during typical drought periods were evaluated. The results showed thatCWDIwp was negatively correlated with soil relative moisture, which could easily identify the starting and ending time, duration andintensity of drought as well as to describe the drought process including occurrence, development, persistence, mitigation and relief more accurately relative to the original model. Moreover, the improved method could be used to daily rolling assessment of regional drought development process, with the assessment result being consistent with the actual situation with a relative error of about 9% for drought areas with different levels.
张淑杰, 张玉书, 陈鹏狮, 梁淑娥, 刘东明, 米娜, 纪瑞鹏, 王阳, 王笑影, 李广霞. 基于改进作物水分亏缺指数的玉米干旱致灾过程识别与动态定量评估[J]. 生态学杂志, 2020, 39(12): 4241-4252.
ZHANG Shu-jie, ZHANG Yu-shu, CHEN Peng-shi, LIANG Shu-e, LIU Dong-ming, MI Na, JI Rui-peng, WANG Yang, WANG Xiao-ying, LI Guang-xia. Identification and dynamic quantitative evaluation of maize drought-induced disaster process based on an improved crop water deficit index.[J]. Chinese Journal of Ecology, 2020, 39(12): 4241-4252.