明清时期京津冀地区蝗灾的时空特征及环境背景*

明清时期（公元1368—1911年）是中国的小冰期，也被称为方志时期，蝗灾等各种自然灾害频发且记录丰富。华北平原是中国历史蝗灾暴发的主要源地，对其开展研究具有特殊的意义。基于明清时期的文献资料，从灾害地理学的视角，借助数理统计与GIS空间分析方法，构建京津冀地区蝗灾等级、频数和县次序列，揭示蝗灾的时空分布特征，并解析其成因。结果表明： （1）明清时期京津冀地区蝗灾平均1.8 a一遇，年均受灾3县次；蝗灾主要发生在夏半年的三月至八月，其中六月和七月是蝗灾暴发的峰值月份，而冬半年的九月至次年二月较少；（2）蝗灾等级以Ⅱ级和Ⅲ级为主，平均等级为2.17；“十年蝗灾频数”和“十年蝗灾县次”整体上呈现波动上升趋势；（3）蝗灾代际县次变化，夏蝗县次多于秋蝗县次，且次年夏蝗的发生与上年暖冬并未良好对应；（4）小波分析指示蝗灾存在100a和30a的主周期和53 a、17 a和11a的次周期；（5）蝗灾空间分布具有一定的集中性，东南远多于西北，受地形起伏和水系格局的影响较大；（6）蝗灾的发生与温度关系不明显，但与旱涝关系密切，并与Nino3指数有良好的对应。

Spatial-temporal characteristics and environmental background of locust plague in Beijing-Tianjin-Hebei region during Ming and Qing Dynasties

Ming and Qing Dynasties(1368-1911 AD),known as the Chronicles Period of China,belong to the Little Ice Age during which locust plague and other natural disasters were frequently occurring and were well registered in historical documents. The North China Plain is the main source area of locust plague in China's history. It is of special significance to do research on the Beijing-Tianjin-Hebei region of North China plain. Based on historical records in the study area during Ming and Qing Dynasties,this paper reconstructed locust outbreak sequences concerning grades,frequency and counties to disclose the temporal dynamics and spatial pattern,and analyzed the causes and environmental mechanism. The results show that: (1)During Ming and Qing Dynasties,locust plague occurred once every 1.8 a and covered 3 counties per year in Beijing-Tianjin-Hebei region. Locust used to occur from March to August of the summer-half year with the peak in June and July. And September to February of the winter-half year was less. (2)The locust outbreak grades ranged mainly between two and three,and the average grade was 2.17. The decadal locust outbreak frequency and decadal locust outbreak counties presented an overall rising trend with fluctuations. (3)The number of counties of summer locust was more than that of autumn locust. Either warm or cold winters had little impact on the following summer locust outbreak. (4)The result of wavelet analysis indicated that periodicity occurred with primary periods of 100 a and 30 a and secondary periods of 53 a, 17 a and 11 a. (5)The spatial distribution of locusts presented a certain geographic clustering with southeast far more than northwest. It was greatly affected by the topography and water system pattern. (6)The locust plague was insignificantly affected by temperature change but had a strong relationship with drought and a good correspondence with the Nino3 index.