关键词: 元素硫, 蔬菜地土壤, 硝态氮, 硝化抑制剂

Abstract: Based on the classification of ecosystem services value and of wetland types, the ecosystem services value of coastal wetlands in the southern Laizhou Bay was calculated by using the Landsat 7 satellite remote sensing images of October 1987 and October 2002, and the temporal change of the value in 1987-2002 was analyzed. The results showed that the material production values of aquatic products and crude salt as well as the values of gas regulation and water regulation were the dominant ecosystem services value of the coastal wetlands in southern Laizhou Bay. The values of gas regulation and water regulation were the primary ecosystem services value of natural wetlands, and those of the material production values of aquatic products and crude salt were the primary ecosystem services value of artificial wetlands. From 1987 to 2002, the total ecosystem services value of the coastal wetlands in southern Laizhou Bay had descended by 28.8%, being from 38.953×10.8 yuan to 27.743×10.8 yuan, and the ecosystem services value per hectare had descended by 29.4%, being from 4.291×10⁴ yuan·hm^-2 to 3.031×10⁴ yuan·hm^-2. The main reason for the decline was that part of natural wetlands had been converted into artificial wetlands, which caused the direct use value of the coastal wetlands in southern Laizhou Bay to rise, but the indirect use value and non-use value to descend. To avoid the decrease of the value, local governments should strictly control the construction of artificial wetlands, and protect the existing natural wetlands.

Key words: Element sulphur, Vegetable soil, Nitrate, Nitrification inhibitor