NPP列入生态统计指标体系的潜力分析——以北京地区NPP测算与空间分析为例

Potential analysis on NPP included as ecological statistical indicators:Taking Beijing vegetation net primary productivity measurement and spatial analysis as an example

通过梳理目前自然资源和生态环境统计指标(简称生态统计指标)定义和使用情况,发现国内统计指标体系的内容框架有待扩展,指标体系亟待标准化。NPP是衡量生态系统对环境气候响应的重要研究指标,可以考虑作为国内生态统计指标体系的有益补充,因而在列入指标体系之前需要在数据来源和模型方面进行统一和验证。以目前最常使用的NPP光能利用率模型进行适用于研究地区的参数改进,利用RS、GIS技术手段,综合MODIS遥感数据、气象数据(每日降水量、每日气温、日照时间)、一些辅助矢量数据等多源信息,计算出北京地区2008年NPP的月度值和全年累计值,目标是为其进入生态指标体系建立一个系统的数据处理规范,以保证NPP统计的一致性、可行性和有效性。结论:从区位统计结果来看,城市核心区和城市功能拓展区NPP的季节性特征变化不明显,而生态涵养发展区的NPP随着时间变化比较大;从地貌统计结果来看,远山区的NPP值大于平原区,也大于半山区。以上结果与温度、降水的季节性变化和耕地的收种时间具有一致性,证明该处理流程可以作为北京地区NPP量化及空间评估的有效手段。表明,NPP的数据来源稳定,测量模型具有可行性和有效性,可以考虑将该指标纳入自然资源和生态环境统计体系。

It has been found that inconsistency norms of the statistical indicator system on natural resources and ecological environ- ment from different release institutions, when reviewing the current definition and employment of them. The study of the net primary productivity （NPP） will contribute to reflect the response of ecosystem toward the climate and environment. When it has been added into the national statistical indicator system, at least two points should be considered, data uniform and the model validation. Based on RS, GIS technologies, using MODIS remote sensing data, meteorological data （daily precipitation, daily temperature, sunshine duration）, some auxiliary vector data, as multi-source information, to drive NPP model （CASA） with the parameters of the study areas improvements, the results are that monthly NPP, as well as yearly accumulation in Beijing. The goal is to give the data proc- essing norm for NPP measurement, in order to ensure the consistency, feasibility, and validity of NPP statistics. The conclusions show that： （1）more prominent seasonal fluctuation existing in the eco-conserving division, than the urban core division and the urban function extension division; （2）the NPP in the mountainous area is larger than the plain area as well as the semi mountainous area. The conclusions mentioned above show the consistency with the seasonal fluctuation of temperature, precipitation, as well as the sowing and harvesting time, which proves the workflow, is an effective one, to give spatial assessment and quantitative measurement in the Beijing area. This paper shows that, considering the data sources stability, the feasibility and effectiveness of the measurement model, NPP can be added into the statistics indicator system of natural resources and ecological environment.