Ecological Benefits Monitoring And Assessment On Water Source Conservation Areas Of Reservoir Under Different Measures Of Ecological Restoration

Taking ecological restoration project on water source conservation area of Taolinkou Reservoir as the research object, the thesis monitored vegetation types and biodiversity variation characteristics, soil improvement benefit, water conservation and storage benefit, and other indexes under different eco- restoration measures. Firstly, the thesis mainly used"space replacing time"method, located monitoring method on the fixed and semi-fixed standard plot, field investigation and indoor test to monitor the ecological benefit indexes of different eco-restoration measures during the eco-restoration process using membership function method.The research can provide scientific basis to quantitatively evaluate eco-restoration benefits of water source conservation area of reservoir. Besides, it can provide scientific basis to accelerate the paces of ecological degradation prevention on the whole watershed and the similar areas in North China.The results showed:(1) The vegetation types andα-diversity increase of eco-restoration area obviously.After eco-restoration, the species richness of natural secondary forest segeneration type is maximum (28 species), with barren slope segeneration type (25 species), steep slope terrace segeneration type(24 species), open forest repair planting type (18 species), plantation segeneration type (17 species), and barren slope afforestation type (17 species) followed.The plant community species diversity and evenness of different eco- restoration measures on the project area increase obviously, where natural secondary forest segeneration type are maximum, and open forest repair planting type, barren slope afforestation type, steep slope terrace segeneration type, plantation segeneration type, and barren slope segeneration type are in order.(2) The soil structure significantly improves, the soil bulk density decreases, and the soil porosities and fertility improve on the eco-restoration area.After eco-restoration, the soil particle composition is dominated by silt and sand, and the soil texture is sandy loam soil, besides, the soil fractal dimension decreases. The soil structure and stability become better.The soil bulk density reduction of different eco-restoration measures ranges from 11.23% to 26.94%, and that of steep slope terrace segeneration type is maximum. While the soil total porosities increase ranging from 14.66% to 31.71%, and that of natural secondary forest segeneration type is maximum, while that of barren slope segeneration type is least; the soil capillary porosities and non-capillary porosities increase respectively ranging from 13.19% to 33.14% , and from 23.20% to 62.54%.The soil fertility improves markedly, including the contents of soil organic matter, total nitrogen, available nitrogen, total phosphorus, available phosphorus, and available potassium. Concretely, soil organic matter content ranges from 27.84g·kg^-1 to 73.40g·kg^-1, increasing from 20.53% to 93.74%; soil total nitrogen content ranges from 1.85g·kg^-1 to 2.43g·kg^-1; soil available nitrogen content ranges from 165.86mg·kg^-1 to 343.43mg·kg^-1; soil total phosphorus content ranges from 7.06g·kg^-1 to 9.51g·kg^-1, soil available phosphorus content ranges from 5.98mg·kg^-1 to 14.30 mg·kg^-1, and soil available potassium content ranges from 60.27mg·kg^-1 to 145.36mg·kg^-1, which increases respectively from 8.19%, 18.59%, 7.02%, 34.15% and 33.71% to 44.12%, 46.48%, 15.27%, 64.75% and 220.68%.(3) The benefits of water conservation and storage increase markedly on the eco-restoration area.The effective litter interception amount of natural secondary forest segeneration type, plantation segeneration type, barren slope segeneration type, steep slope terrace segeneration type, open forest repair planting type, and barren slope afforestation type respectively are 8.51mm, 4.51mm, 2.86mm, 3.92mm, 5.13mm, 5.22mm, which increases respectively ranging from 20.41% to 98.63%.The available soil water content of natural secondary forest segeneration type and plantation segeneration type respectively is 42.25mm and 34.23mm. Besides, that of barren slope segeneration type, steep slope terrace segeneration type, open forest repair planting type, and barren slope afforestation type respectively is 19.58mm, 19.53mm, 33.06mm, and 27.20mm, which increases respectively ranging from 26.24% to 50.94%. What's more, the soil water content of forest land segeneration type is more than that of other eco-restoration measures.The soil water holding capacity of natural secondary forest segeneration type is 423.25 t·hm^-2, while that of plantation segeneration type is 342.46 t·hm^-2. The soil water holding capacity of barren slope segeneration type, steep slope terrace segeneration type, open forest repair planting type, and barren slope afforestation type adds up respectively from 26.28% to 50.50%, reaching 195.84 t·hm^-2 195.66 t·hm^-2, 329.53 t·hm^-2, and 271.98 t·hm^-2.The total water storage of different eco-restoration measures is higher than before restoration. The total water storage of natural secondary forest segeneration type is maximum, reaching 236.35mm, followed by that of open forest repair planting type(222.93mm), plantation segeneration type(206.86 mm), barren slope afforestation type(168.61mm), steep slope terrace segeneration type(121.14mm), barren slope segeneration type(101.24mm). While the available water storage respectively is 50.76mm, 38.19mm, 38.74mm, 32.42mm, 23.45mm, 22.44mm.(4) The membership function method was used to evaluate the ecological benefits. The evaluation result shows that the ecological benefit of natural secondary forest segeneration type is best, that of open forest repair planting type, steep slope terrace segeneration type, barren slope afforestation type, plantation segeneration type, and barren slope segeneration type are in order.