南方草地NPP的水热估算模型及其应用  

Estimation model and the application of grassland NPP based on precipitation and temperature in south China

作　　者：孙成明[1] 刘涛[1] 陈雯[1] 陈瑛瑛[1] 田婷[1] 李建龙[2] 

机构地区：[1]扬州大学农学院江苏省作物遗传生理国家重点实验室培育点,江苏扬州225009 [2]南京大学生命科学学院,江苏南京210093

出　　处：《生态环境学报》2013年第9期1457-1461,共5页Ecology and Environmental Sciences

基　　金：国家重点基础研究发展计划(973计划)项目(2010CB950702);国家高技术(863计划)专题项目(2007AA10Z231);江苏高校优势学科建设工程资助项目(2011-05);APN全球变化基金项目(ARCP-2012-FP28-Li)

摘　　要：草地NPP对气候变化的响应是全球变化研究的重要内容之一。为了明确草地NPP与水热的关系及实现南方草地NPP的大面积估算,本文以气候数据为基础,以南方草山草坡为研究对象,结合野外实测数据,分析南方草地NPP与月平均温度及平均降水量之间的关系,结果表明:南方草地NPP与月平均温度之间呈对数相关,相关系数r=0.462 9**(n=66);与月平均降水量之间呈线性正相关,相关系数r=0.783 6**(n=66),结果均达到了极显著水平(P<0.01)。在此基础上构建以温度和降水为自变量的南方草地NPP估算模型:NPP=Ln(T/16.7+2.5)×Sqrt(W/84.5+0.5)×(T+W),其中T为全年月平均温度(℃),W为全年月平均降水量(mm)。通过不同年份的实测数据对模型进行验证,草地NPP的模拟值和实测值之间有很好的相关性,R2为0.787,也达到极显著水平,RMSE和RRMSE均较小,分别为60.272和0.387,表明模型的模拟结果比较可靠。利用上述模型对2011年的南方草地NPP进行估算,模拟结果呈现一定的地带性,总体分布由西北向东南逐渐增加,其中四川西北部及其与云南交界等地区草地NPP值较小,基本在200 g·m-2以下,而海南、广西、江西以及广东等地草地NPP值较高,相当一部分地区达到700 g·m-2以上。通过分析可知,整个南方草地NPP平均值约为321.8 g·m-2左右,和实测结果比较接近。结果为南方草山草坡NPP估算提供了新的方法。The response of grassland NPP to the climate change is one of ‘hot topics’ of global change researches. In order to quantify the relationship between grassland NPP and precipitation and temperature, and to estimate the grassland NPP of south China in large scales, this paper analyzed the grassland NPP of south China, the mean monthly temperature, and the mean monthly precipitation from the climate data and field data. The results showed a logarithm relationship between the grassland NPP and the mean monthly temperature and the correlation coefficient was 0.462 9 （P〈 0.01, n=66）. The grassland NPP was also linearly correlated with the mean monthly precipitation and the correlation coefficient was 0.783 6 （P〈0.01, n=66）. The estimation model of NPP in the southern grassy mountains was constructed with temperature and precipitation as the independent variables based on the above results, and it was NPP=Ln（T/16.7＋2.5）×Sqrt（W/84.5＋0.5）×（T＋W）, where T was the mean monthly temperature （℃） in a year, and W was the mean monthly precipitation （mm） in a year. The model was validated by the observed data in different years and there was a good correlation between the simulated and observed NPP values, and R2 was 0.787, reaching a very significant level too. The RMSE and RRMSE were small, and the values were 60.272 and 0.387, respectively, which indicated that the model was reliable. The southern grassland NPP in 2011 was estimated by using the model and the simulation results presented a zonality. The distribution of grassland NPP increased gradually from northwest to southeast, and the values of the grassland NPP in northwest of Sichuan and the border regions with Yunnan were the lowest, and they were less than 200 g·m-2. The values of the grassland NPP in Hainan, Guangxi, Jiangxi, and Guangdong were the highest, and they were more than 700 g·m-2 in a number of areas. The analysis result showed that the mean value of grassland NPP in south China was about 321.8 g·m-2, and it

关 键 词：应用 月平均降水量 月平均温度 估算模型 草地NPP 南方 

分 类 号：S127[农业科学—农业基础科学]