土地利用方式改变对红树林沉积物中营养元素含量的影响

以广西、广东、海南等地代表性红树林湿地为对象,研究红树林湿地利用方式的改变对沉积物有机碳、总硫、总氮和总磷等营养元素的含量变化和影响,结果表明：1）广东和海南红树林区总氮和总磷变化相似,均为：沉积物〉农田〉鱼塘〉光滩,广西大冠沙稍有不同,光滩的氮磷含量最低;有机碳和总硫含量各地稍有差异,但是红树林沉积物中的有机碳,总硫...

Impact of Different Land Use Modes on Nutrients of Sediments from Mangrove Wetlands of China

This study aims at evaluating impacts of mangrove wetland-use on the levels of organic carbon,total surfer,total nitrogen and total phosphorus in sediments from major mangrove wetland ecosystems in Guangxi Autonomous Region,Guangdong and Hainan Island,China.Our results show that: 1) both Guangdong and Hainan displayed the same pattern for total nitrogen and total phosphorus,decreasing in the order of sediment> farmland> pond> mudflat;within a slightly different order,the lowest levels for total nitrogen and total phosphorus were also observed in the mudflat of Guangxi Daguansha mangrove wetland.As to the concentrations of organic carbon and total surfer,although a slight difference was detected,all the three districts exhibited greater values in mangrove sediments,with the levels of mudflat being the lowest;2) based on loss amounts from Guangdong,Guangxi and Hainan,we further calculated the nationwide loss amounts of organic carbon,total sulfur,nitrogen and phosphorus(3.05×1012 g,2.68×1011 g,2.94×1012 g and 0.377×1011 g,respectively) and it can be concluded that changes in land use mode escalated the loss of organic carbon,surfer,nitrogen and phosphorus in soils,thus leading to gradual soil erosion in mangrove wetlands.