基于SPA模型的森林生态系统净初级生产力空间分布

NPP Spatial Distribution of Forest Ecosystem Based on SPA Model

森林生态系统净初级生产力(NPP)是森林生态系统碳循环的原动力,是陆地森林生态系统碳循环的重要组成部分,它代表了森林生态系统固定大气中CO2的能力,对森林生态系统能否降低大气CO2浓度及抑制全球变暖趋势的评估起着重要作用。根据英国爱丁堡大学的森林生态系统碳循环SPA模型的特点,以遥感信息数据作为主要的数据源,将该模型从斑块尺度模型到区域尺度模型进行扩展,并以数据并行技术作为解决模型扩展后计算时间过长的手段,建立新的森林生态系统碳循环动态过程模型RSPA,利用该模型对福建省三明市尤溪县2007年森林生态系统NPP进行模拟与验证。结果表明,2007年尤溪县森林生态系统NPP值季节变化空间分布明显,其6-9月是森林植被生长旺盛的季节,NPP出现增长峰值,而其他月份则NPP值相对较小。在森林植被固碳能力方面是阔叶林>竹林>杉木林>马尾松林。

The forest ecosystem Net Primary Productivity （NPP） is the driving force for the forest ecosystem carbon cycle and an important component in the terrestrial forest ecosystems carbon cycle, because it represents the capacity of the forest ecosystem to fix CO2 in the atmosphere. NPP plays a significant role in assessing whether the concentration of CO2 can be reduced in the atmosphere and the biosphere can be protected against global warming or not. Based on the British Edinburgh University＇s forest ecosystem carbon cycle SPA （Soil-Plant-Atmosphere） model, and using the remote sensing data as a major source of the data to expand the model from a patch model to a region model, this paper presents a new forest ecosystem carbon cycle dynamic process RSPA （Region Soil-Plant-Atmosphere） model, with the aid of the data parallel computing and the cluster technology as a solution to the excessively long computing time due to the model expansion. This model is used to simulate and verify the NPP of the forest ecosystem in Youxi County, Sanming City, Fujian Province in 2007. The results show clearly the NPP seasonal spatial distribution variation of Youxi County forest ecosystem in 2007. Its forest cover plants grow during the exuberant season from June to September, where the NPP provides the growth peak value, but other months＇ NPP values are relatively small. With respect to the forest cover plant solid carbon ability, we have： the broad-leaved forest〉 bamboo〉Chinese fir〉pine forest.