基于景观格局的现代黄河三角洲滨海湿地土壤有机碳储量估算

Estimation of Soil Organic Carbon Storage in Coastal Wetlands of Modern Yellow River Delta based on Landscape Pattern

利用2000年和2009年的TM影像数据,对现代黄河三角洲滨海湿地的景观进行分类,将其划分为9种景观类型。利用ArcGIS9.3软件,依据2009年黄河三角洲滨海湿地GPS土壤定点采样点的理化分析数据,计算出土壤有机碳密度,并进行空间插值,结合各景观类型分布面积,估算表层(0～30cm深度)土壤有机碳密度和储量。研究结果表明,2000～2009年,研究区的总面积增加,土壤有机碳密度为0.73～4.25kg/m2;2000年和2009年的土壤总有机碳储量分别为3.43×106t和3.17×106t。各景观类型的土壤有机碳储量随着其面积的变化而变化,面积变化最明显的景观类型是滩涂、灌草地、农田和盐田养殖池,导致这种变化的原因是自然因素和人为因素共同作用的结果。减少和限制人类活动、保护表层土壤对黄河三角洲滨海湿地土壤碳库的持续稳定发展非常重要。

Appling Landsat TM digital images of 2000 and 2009 for the modern Yellow River Delta,the landscape of the modern Yellow River Delta was divided into nine different landscape types.The soil organic carbon density was calculated based on the laboratory data of soil samples from field investigations in 2009.The soil organic carbon density was spatially interpolated by Kriging interpolation method of ArcGIS.Combined with areas of landscape types,the soil organic carbon stocks （0-30cm） of the modern Yellow River Delta in 2000 and 2009 were estimated.The results showed that the soil organic carbon densities varied in the range from 0.73 kg/m 2 to 4.25 kg/m 2 and the soil organic carbon storages were estimated about 3.43×10 6 t in 2000 and 3.17×10 6 t in 2009.Although the total areas of the modern Yellow River Delta increased a lot from 2000 to 2009 because functions of silt deposit in the estuary,the difference of soil organic carbon storage was little.Because of the dramatic changes of landscape areas,the changes of soil organic carbon storages at landscapes of beaches,bush-grassland,and farm land and saline aquaculture pone increased from 2000 to 2009.Through the driving force analysis,we found that the results was caused by both natural and anthropogenic factors.Therefore,reducing and limiting human activities on destructing wetlands is an effective way to ensure the stable development of soil carbon pool of coastal wetlands in the modern Yellow River Delta.