江苏千年蝗灾的时空特征与环境响应

Spatiotemporal characteristics and environmental response of locust plague in Jiangsu Province during the past one thousand years

利用史料记录建立了江苏北宋至民国近千年来的蝗灾数据库,构建蝗灾等级序列和10a尺度上的蝗灾频次序列,再现蝗灾发生的时空特征,探讨了蝗灾动态与河湖环境变迁及气候变化的关联。结果表明:宋至民国时期江苏有282个蝗灾年份,平均2.8a/10a;蝗灾整体上呈现增多的趋势,蝗灾频次统计揭示有7个蝗灾高发期和7个蝗灾低发期。苏北和苏南地区蝗灾频次和升降趋势整体上较为一致,苏南灾情更甚。小波分析显示,蝗灾暴发没有显著的周期性。江苏历史蝗灾空间分布具有明显的"水缘性"特征,相对集中于湖泊周围和河流沿岸地区,亦有逐步向南、向东扩散的趋势。蝗灾与温度关系不明确,与干旱较为一致。未来亟需开展历史蝗区演化与水系变迁及蝗灾代次细化与追踪溯源研究,以获得更加深入的认识。

Based on the historical records of locust outbreaks in Jiangsu Province, this study established the data- base of locust plague from Song to the Republican period and reconstructed locust outbreak grades sequence and 10 -year scale frequency sequence, aiming to explore the spatiotemporal characteristics, the linkage or relationship between locust outbreaks and lake/river environmental change and climate change. Results show that, 282 locust years occurred in Jiangsu province during this period, with an average frequency of 2.8a/10a; the locust shows an overall increase trend ; there are seven high - incidence periods and seven low - incidence periods. North and south Jiangsu regions present almost the same frequency change and rise -fall trend, with a few more serious locust e- vents in the south. Wavelet analysis indicates that, historical locust outbreaks do not have periodicity during this period. The spatial distribution of locust outbreaks displays the an obvious attachment nature of the locust plague to water： the plagues gather relatively more in the areas around lakes and rivers, with a southward and eastward diffu- sion trend. Locust plague is insignificantly affected by temperature change but has a strong relationship with drought. Fine and retrospective analysis of different generations of locusts plague are required to be conducted in further researches.