海南岛土壤体积含水量变化规律及其与气候因子的关系

Soil Volume Water Content Change and Its Relationship with Climate in Hainan Island

为海南岛的农业生产指导和气候评价提供科学依据,采用统计学方法以及基于地理信息系统的空间分析方法对2013—2017年海南省18个农业气象观测站的土壤体积含水量数据及气温、降水数据进行分析,讨论海南岛土壤水分的分布特征,并对其气候影响因子进行初步分析。结果表明:1)海南岛气温空间分布特征以中部山区为中心,四周气温升高,西部、南部至东南沿海地区气温为全岛最高,降水基本集中在海南岛中东部地区。2)随着土壤深度加深,受到外界环境及气候条件的影响相对较小,基本的变化是3月后,不同土层的土壤体积含水量随着时间的推移呈上升趋势,至9月后,呈下降趋势。除30~40cm土层是在10月出现最大值,其余各土层的土壤体积含水量均在9月出现最大值。3)0~20cm土层中土壤水分的交换较为频繁,受外界水热因子影响较大,空间分布以西北-东南为分界线,分界线以东的地区土壤含水量偏大,屯昌除外;分界线以西的地区土壤含水量偏小。4)在湿润区与半湿润区,土壤体积含水量受降水量的影响较气温大,而半干旱区主要影响因素是气温。

To provide scientific basis for agricultural production guidance and climate evaluation in Hainan Island,the data of soil volumetric water content,air temperature and precipitation of 18 agrometeorological stations in Hainan Province from 2013 to 2017 were analyzed by statistical method and spatial analysis method based on GIS.The distribution characteristics of soil moisture in Hainan Island were discussed,and the climate influencing factors were analyzed either.Results:1)The spatial distribution characteristics of air temperature in Hainan Island were centered in the central mountainous area,and the temperature increased around it.The temperature in the western,southern and southeast coastal areas was the highest in the whole island,and the precipitation was basically concentrated in the central and eastern part of Hainan Island.2)With the deepening of soil depth,the influence of external environment and climatic conditions was relatively small.The basic change was that the soil volumetric water content of different soil layers increased with the passage of time after March,and decreased after September.The soil volumetric water content of all soil layers reached the maximum in September except that the soil volume water content of 30-40 cm soil layer gained the maximum in October.3)The exchange of soil water in 0-20 cm soil was more frequent,which was greatly affected by external hydrothermal factors.Taking the northwest-southeast as the dividing line,and the soil water content in the area to the east of the dividing line was on the high side,except in Tunchang.The soil water content in the area to the west of the dividing line was small.4)In humid and semi-humid areas,the influence of precipitation on soil volumetric water content was greater than that of air temperature,while the main influencing factor in semi-arid area was air temperature.