Variation trend of dry-wet climatic factors and correlation with wetlands in western Jilin Province, China

The variation of climate elements and its relationship with wetland landscape in western Jilin Province (WJL) were studied to support decision-making for drought prevention and ecology protection. Mann-Kendall test and linear regression algorithm methods were used to analyze the characteristics of climate change, using a large amount of data of temperature, precipitation, evapotranspiration and dry-wet index, collected from nine monitoring stations during 1960-2014. The results showed that annual temperature and dry-wet index in WJL displayed a ascendant tendency, with the average rate of 0.34℃/10a and 0.14/10a, respectively. The annual precipitation and potential evapotranspiration showed a declining trend; decreasing by about -7.92mm/10a and -3.4mm/10a, respectively. Homogeneous trend was found for temperature and evapotranspiration in the autumn; an increasing trend observed. A sharp declining trend was found in the summer season for precipitation, which was the biggest contributor to the overall decrease of annual precipitation. The spatial distribution of annual and seasonal climate factors indicated that the WJL area is becoming drier, especially in the summer and autumn seasons. The wetland landscape indexes in most regions are significantly correclated with summer precipitation. The significance level for I, II and IV regions located in the west of WJL reached 99%. It is important to plan responding measures of water resource management, to counter the decrease of summer precipitation in western WJL, and reduce the impact of drought and wetlands degradation, which is possibly caused by the global climate change