| 摘要: |
| 掌握降水及降雨侵蚀力的时空分布和演变特征对于揭示区域气候变化规律，有效预防和科学评估水土流失等环境问题具有重要意义。基于34个气象站点1961—2015年的降水日值数据，采用降雨侵蚀力计算模型、Mann-Kendall检验、小波分析和Kriging空间插值等研究方法，分析研究了山东省内山地、丘陵和平原等不同地形区的降水和降雨侵蚀力时空变化特征。结果显示：近55年间，全省及各地形区的降水量和降雨侵蚀力均呈波动下降趋势，年内分配均集中在夏季，降雨侵蚀力在时间尺度上存在25年左右的变化周期。空间上，降水和降雨侵蚀力均呈现鲁中南山区＞胶东半岛丘陵区＞鲁西北平原区；分界线由东北至西南沿福山—莱阳—淄博—定陶等站呈“S”型贯穿山东省，界线东南侧降雨侵蚀力高，西北侧降雨侵蚀力较低。其原因主要是受海拔和地形的影响，东南季风携带湿润气流受胶东半岛丘陵及鲁中南山地的阻挡抬升，致使“S”型分界线东南侧迎风面降水及降雨强度相对较高；西北侧背风面形成焚风效应，降水及降雨侵蚀强度较低。该结果可为山东省水土流失空间特征分析奠定数据基础，同时为区域水土资源利用与调控及生态环境保护与改善提供决策支撑。 |
| 关键词: 降雨侵蚀力 时空变化 不同地形区 山东省 |
| DOI：10.7515/JEE182079 |
| CSTR：32259.14.JEE182079 |
| 分类号: |
| 基金项目:山东省重点研发计划项目（2018GSF117021）；山东省高等学校科技计划项目（J17KA192）；中国科学院海岸带环境过程与生态修复重点实验室开放基金项目（2016KFJJ03）；国家自然科学基金项目（41530854） |
| 英文基金项目:Shandong Provincial Key R & D Program (2018GSF117021); Science and Technology Projects of Shandong Universities (J17KA192); Open Foundation of Key Laboratory of Coastal Environmental Processes and
Ecological Remediation, Chinese Academy of Sciences (2016KFJJ03); National Natural Science Foundation of China (41530854) |
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| Spatial and temporal variations of rainfall erosivity in different topographic regions of Shandong Province |
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XIAO Bei, CUI Buli, JIANG Baofu, LI Dongsheng, WANG Ying, ZHAO Tao
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1. School of Resources and Environmental Engineering, Ludong University, Yantai 264025, China
2. Bureau of Land and Resources of Longkou, Yantai 265701, China
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| Abstract: |
| Background, aim, and scope The problem of water and soil loss in China was serious, and it was increasingly serious in Shandong Province in recent years. Rainfall erosivity is one of the driving force of this ecological issue while precipitation is the primary cause of rainfall erosivity, thus the research of precipitation and rainfall erosivity are necessary, which would contribute to comprehensively understand the knowledge about the regional climatic change and the water resources utilization situation. This paper wrote with the study area of the three topographic regions (Jiaodong Peninsula Hilly Area (JDPHA), Luzhongnan Mountainous Area (LZNMA), and Luxibei Plain Area (LXBPA)) in Shandong Province for investigate the spatial and temporal variations of the precipitation and rainfall erosivity as well as their regional difference under the influence of topography, aim to provide insight into the prevention and control of water and soil loss as well as the protection and restoration of ecological environment. Materials and methods Based on the daily precipitation data of 34 meteorological stations in Shandong Province from 1961 to 2015, the spatio-temporal precipitation and rainfall erosivity variations respectively in Shandong Province and the three topographic regions were analyzed by using the mathematical statistics methods of coefficient of variation, Mann-Kendall test, wavelet analysis and Kriging interpolation. Results The results showed that annual precipitation and rainfall erosivity of Shandong Province fluctuated and declined slightly during the period from 1961 to 2015 with the average annual precipitation of 681.3 mm and the average rainfall erosivity of 4236.3 MJ·mm·hm−2·h−1·a−1. The three topographic regions all showed the same fluctuated and slightly declined trends during the 55 years, among which, JDPHA was more obvious with the climate tendency rate of −11.6 mm·(10a) −1 and −10.0 MJ·mm·hm−2·h−1·a−1 in precipitation and rainfall erosivity, respectively. The annual precipitation and rainfall erosivity were concentrated mostly in summer, the sum of precipitation and rainfall erosivity in June to August occupy for 60% and 70% of the year, respectively. The rainfall erosivity had a main period of 25 years. For the spatial characteristics of precipitation and rainfall erosivity, they all decreased gradually from the southeast to the northwest, while the values of the three regions were in the order of LZNMA＞JDPHA＞LXBPA. The study area should be divided into two parts by the “S” type boundary line through Fushan, Laiyang, Zibo, and Dingtao weather stations. High precipitation and rainfall erosivity were at the southeast side of the line, while relative low precipitation and rainfall erosivity were at the northwest side of the line. Discussion Influencing factors of the distribution and variations of rainfall erosivity were discussed. Altitude and topography also played an important role in influencing precipitation and rainfall erosivity. High precipitation and rainfall erosivity emerged on the southeast side of hilly areas (JDPHA and LZNMA) due to high moisture, climbing airflow on the windward slope of mountains, derived from the Southeast Asian Monsoon, while relative low precipitation and rainfall erosivity emerged on the northwest side of hilly areas (LXBPA) due to the foehn effect. Statistics showed that the precipitation and rainfall erosivity would increase with the rising of elevation, of which, the stations which altitude higher than 50 m the correlation coefficients of precipitation, rainfall erosivity and elevation all showed the significant level at 0.01, while the stations which lower than 50 m were not so obvious but also showed the positive correlation. Conclusions The annual and monthly variations of the precipitation and rainfall erosivity of the three topographic regions all showed the same trends with Shandong Province during the period from 1961 to 2015, but there are minor differences among each topographic region in the coefficient of variation, climate tendency rate and the periodical variations of rainfall erosivity. Shandong Province have been divided into two parts by the “S” type boundary line that influenced by the altitude and topography, the southeast side had high precipitation and rainfall erosivity whereas the northwest side was quite the opposite. Besides, the higher the altitude the more obvious positive correlation of the precipitation, rainfall erosivity and elevation. Recommendations and perspectives It’s necessary to plan and deploy the water and soil conservation with the stress on prevent and control water and soil loss in summer in Shandong Province, especially in JDPHA and LZNMA. The southeast monsoon is the key factor that influence the precipitation and rainfall erosivity, the altitude and topography work too, but in addition, other natural and human factors like temperature, vegetation coverage, soil property, agriculture development, urban expansion also play important roles in the spatial and temporal variations of precipitation and rainfall erosivity, that will be the further research to promote the rational use of regional water resources and accelerate the conservation and restoration of the eco-environment. |
| Key words: rainfall erosivity spatial and temporal variation topographic region Shandong Province |
