平潭岛木麻黄碳储量遥感估测

Remote sensing estimation of Casuarina equisetifolia carbon storage in Pingtan Island

为快速获取选定研究区域内的碳储量,以福建省平潭综合实验区主岛栽植的木麻黄为研究对象,采用遥感与地理信息系统技术对平潭主岛2014年9月美国国家航空航天局陆地卫星影像(Landsat OLI)8进行处理,结合归一化比值植被指数(NDVI)与专家知识分类为基础的像元扩张法对木麻黄林分信息进行提取。结果表明,扩张法对木麻黄林地分类总体精度80.6%,与专家分类相比提高了9.6%。根据采集木麻黄样本生物量与含碳率估测研究区木麻黄碳储量,结果表明平潭主岛木麻黄碳储量总量为331 308.09 t,单位面积碳储量为75.48 t·hm-2,生物量为151.88 t·hm-2,均处于中等水平。其中潭城镇木麻黄碳储量最高,平原镇、流水镇木麻黄碳储量较高,白青乡、中楼乡、岚城乡等地木麻黄碳储量一般,苏澳镇、北厝镇木麻黄碳储量较低。从岛上木麻黄分布情况分析,平潭主岛北部、中部、南部的乡镇均有分布较为集中的地块,而苏澳镇、潭城镇、白青乡整体分布较少。

To obtain the carbon storage in research area, Casuarina equisetifolia in the main Island of Pingtan Comprehensive Experimental Community in Fujian Province was taken as the research object and OLI images of main Pingtan Island in September 2014 were processed by the RS and GIS technology. Meanwhile the C. equisetifolia information was extracted by NDVI and the knowledge of repeat pixel expansion classification. Results revealed that pixel expansion classification overall accuracy was 80.6%, higher than the expert knowledge classification 9.6%. The C. equisetifolia carbon storage in the research area was estimated according to the values of sample biomass and C. equisetifolia carbon storage rate. The result showed that the main Pingtan Island C. equisetifolia carbon storage amounted to 331 308.09 t, 75. 48 t-hm-2 on average, biomass was 151. 88 t-hm-2 , the values of C. equisetifolia biomass and carbon storage of the whole research area were medium. Particularly, Tancheng Town had the highest C. equisetifolia carbon storage, followed by Pingyuan and Liushui. And the C. equisetifolia carbon storage in Baiqing, Zhonglou and Lancheng towns kept at the averaged level, which were higher than those in Suao and Beicuo towns. According to analysis of the distribution of C. equisetifolia in Pingtan Island, there were more concentrated distributions of C. equisetifolia in the northern, central and southern towns of Pingtan Island, while less distribution in Suao Town, Tancheng Town and Baiqing Town.