PROGRESS IN GEOGRAPHY ›› 2010, Vol. 29 ›› Issue (11): 1375-1384.

• Original Articles •

### Study on Social Influence, Environmental Significance and Ecological Explanation of the Dynamics of Locust Plagues in China During the Historical Period

LI Gang1, WANG Naiang2, LI Zhuolun2

1. 1. College of Urban and Environmental Sciences, Northwest University, Xi'an 710127, China;
2. College of Earth and Environment Sciences, Lanzhou University, Lanzhou 730000, China
• Received:2010-01-01 Revised:2010-05-01 Online:2010-11-25 Published:2010-11-25

Abstract:

The process of Chinese social-economic development was a long struggle history. Flood, drought and locust plague were the three biggest natural disasters in Chinese history. Flood and drought which had a close relationship with climate change have been studied by many researchers for a long time. As for locust plague, more attention should be paid to it. Accordingly, through collection and interpretation of Chinese historical documents related with locust plague, we set up a Chinese historical locust plague database according to which the trend and characteristics of locust plagues were disclosed. As for the three subspecies of migratory locusts in China, we made a sublevel regionalization map of them. According to the database and the map, we constructed many historical locust plague sequences. More work was done to deal with comparisons between locust plague sequences and sequences of other natural disasters, social crises, and climate proxies—mainly temperature and precipitation. Finally, we drew a preliminary conclusion of the social influence and environmental significance of historical locust plagues, to which ecological explanation was also given. We did several comparisons between locust plague sequence and war sequence, epidemic sequence, dust storm sequence, rice price index, and flood sequence of Huaihe River. The results were as follows. Firstly, locust plagues had close correlations with wars and epidemics, which indicated the causality among them. Secondly, locust plagues had a good coherence with dust storms, but it did not mean that cold background was indispensable for locust plagues. Thirdly, locust plagues in Anhui had no overlapping year with floods of the Huaihe River, which in reverse proved the coherence between locust plague and drought. Fourthly, we found that rice price ascended always with a 1-3 year lag after locust plague, which inspected and verified the fact in history. Through construction of next year tables of warm and cold winters in North and East China, we found the recurring probabilities of locust plagues in the two tables were 89/126=0.7063 and 64/85=0.7529, with a difference of 0.0466. The result indicated that locust plague did not have a positive correlation with either warm or cold winter, and locust plague sequence could not be used to reconstruct winter half-year temperature. In a worldwide field of view, we made comparisons between several representative locust plague sequences and typical climate sequences. We found that locust plagues of Core Region had a good tele-connection with ENSO, and locust plague still had bad coherence with temperature, but good with drought. Ecological explanation was given. In summary, our study was an integrated study on social influence and environmental significance of locust plagues in China during the historical period, and the study was an integrated work based on historical data, geographical methods and ecological explanation.