基于净初级生产力的广西喀斯特区生物多样性维护功能评价

Evaluation of Biodiversity Maintenance Function in Karst Area of Guangxi Based on Net Primary Productivity

采用MODIS-NDVI数据、气象数据、土地覆被数据,利用光能利用率模型,估算2000~2017年的广西喀斯特区的植被净初级生产力(NPP),分析广西喀斯特区植被NPP时空演变特征;运用气候方程法,构建广西喀斯特区气候资源空间分析模型,分析广西喀斯特区气候资源时空分布特征;在此基础上,结合地形因子,构建基于NPP的广西喀斯特区生物多样性维护功能定量评价模型,分析广西喀斯特区生物多样性维护功能空间分布特征。结果表明:广西喀斯特区大部分为生物多样性维护功能重要区,以植被生态系统类型为空间尺度,生物多样性维护功能重要性特征表现为灌丛>农田植被>草丛>其他;以市县为空间尺度,生物多样性维护功能重要性特征表现为,由南向北、由东向西逐步递增趋势,重要、极重要区占50. 6%,主要分布在百色、河池、崇左等国家级、市级山地自然保护区,一般重要区只占24. 5%,主要分布贵港、玉林、桂林、贺州、来宾等地市自然灾害发生频繁、人类活动干扰频繁地区。基于较高空间分辨率的NPP,采用“3S”技术开展生物多样性维护功能定量评价,可以为区域生态保护空间精准定位提供技术支撑。

In order to provide theoretical support and decision basis for ecological protection in karst area, the evaluation method of ecological diversity service capacity in karst area is studied.Based on MODIS-NDVI data,meteorological data,land cover data,the net primary productivity (NPP) of vegetation were estimated in the karst area of Guangxi from 2000 to 2017 by using the light energy utilization model,and the spatial and temporal evolution characteristics of vegetation NPP in Karst area of Guangxi were analyzed.The spatial analysis model of climate resources in karst area of Guangxi is constructed using the method of climate equation,and the spatial and temporal distribution characteristics of climate resources in karst area of Guangxi were analyzed.The quantitative evaluation model of biodiversity maintenance function were established in Guangxi karst area based on NPP,and the spatial distribution characteristics of biodiversity maintenance ability in Guangxi karst region were analyzed.The service capacity of biodiversity in most areas of karst in Guangxi are relatively good.On the spatial scale of vegetation ecosystem types,the important characteristics of biodiversity maintenance function are as follows: shrub > farmland vegetation > grassland > others;On the spatial scale of cities and counties,the importance of biodiversity maintenance function shows a gradual increasing trend from south to north and from east to west.Important and extremely important areas accounting for 50.6%,mainly distributed in Baise,Hechi,Chongzuo,and the areas with national and municipal nature reserves.Generally important areas accounting for only 24.5%,mainly distributed in Guigang,Yulin,Guilin,Hezhou and Laibin,where natural disasters occur frequently and human activities interfere frequently.With high spatial resolution of NPP,quantitative assessment of biodiversity maintenance function can provide technical support for precise positioning of regional ecological protection space based on "3S".