土地利用/覆被变化对产水服务功能的影响:以海南热带雨林国家公园为例

Impact from land use/land cover change on function of water yield service: a case study on national park of hainan tropical rainforest

为揭示海南热带雨林国家公园土地利用/覆被变化(LUCC)对产水服务功能时空演变的影响,应用GIS和InVEST模型,分析产水服务功能对LUCC的响应及其成因。结果表明:(1)1990—2018年研究区土地利用发生较大变化,耕地、草地及天然林分别减少68.48%、18.74%及4.89%;水库坑塘、橡胶林和经济林分别增加810.74%、190.42%和38.09%。(2)产水服务功能对LUCC产生明显变化响应,1990—2018年产水总量和产水服务功能总体呈先下降后轻微上升趋势。四期平均产水深分别为1 251.74 mm、1 191.98 mm、1 086.48 mm和1 204.98 mm,并整体呈现出西部产水量低,东部高的空间差异。LUCC是影响产水服务功能变化的重要原因,其中耕地、天然林面积锐减,橡胶林等经济林和水库坑塘面积增加会削弱产水服务功能。因此,未来应合理控制橡胶林等经济林面积,优化配置用地格局。

In order to reveal the impact from land use/land cover change(LUCC) of the National Park of Hainan Tropical Rainforest on the spatial-temporal evolution of water yield service function, the response of water yield service function to LUCC and the causation are analyzed by means of GIS and InVEST model. The results show that(1) the land use in the study area is greatly changed within the period of 1990~2018, for which cultivated land, grassland and natural forest are reduced by 68.48%, 18.74% and 4.89% respectively, while reservoirs as well as pits and ponds, rubber plantation and economic forest are respectively increased by 810.74%, 190.42% and 38.09%;(2) obvious changing response is generated from the water yield service function to LUCC and the total water yield and water yield service function generally exhibit the trends of decreasing at first and then slightly rising. The mean water yield depths of the relevant four study phases are 1 251.74 mm, 1 191.98 mm, 1 086.48 mm and 1 204.98 mm respectively and the water yield wholly presents a spatial difference of lower in the west and higher in the east. LUCC is the important cause to affect the change of water yield service function, in which the sharp reductions of cultivated land and natural forest area and the increases of the areas of the economic forests such as rubber plantation, etc. and reservoirs as well as pits and ponds can weaken the water yield service function. Therefore, the areas of the economic forests such as rubber plantation, etc. are necessary to be reasonably controlled and the the land use pattern must be optimally allocated as well.