| Based on researching the situation of water and soil erosion and its management in the north of Fujian, close measurements, level terrace, hillside ditch, planting trees and grass, orchard, Hedge of Vetiver Grass, Schima superba forest , fir forest lands are sampled. By means of experiments on shrub runoff-plot, fixed point measurements and fixed point surveys to explore benefit from the technique in dealing with water and soil erosion and seek out the good way with better effects of soil , fertilization and moisture conservation to control it. These can accelerate the management of water and soil erosion in north Fujian. These also can protect the environment of the Minjiang River. The results as follows:(1) Through 9 years' close measurement in open forest and young forest, the water in soil are added by average 97. 5 tons of water per hectare per year, soil erosion is reduced by 227.3 tons per square kilometer.(2) In terrace the rate of sediment reduction by water and soil conservation is 96.2%. The terrace with covering plants can reduce soil erosion effectively. It is also can improve organic matter content, total nitrogen content, total phosphorus, total K content.[3] The soil erosion amount of hillside ditch with grasses is reduced with the rate of covering, and to zero in 4 years. It also has a high rate of land using, lower cost, and mechanization.(4) The water in soil and the runoff is influenced by the covering. The higher of the covering, the higher of the water rate, and the lower of the runoff. The plant covering can keep soil apparently, the soil erosion is reduced 86.26 percent than clean tillage. The watercontent of soil with straw is higher than plant covering in 2. 1 percent, soil erosion is higher in 6.2 percent.(5) When planting hedge of vetiver grass in contour line of longitudinal slope with socket, the runoff and erosion can each reduce 33. 9 percent and 95. 9 percent. The runoff and erosion can each reduce 82. 2 percent and 45. 2 percent with planting Hedge of Vetiver Grass on ridge platform orchard than without planting.(6) Artificial afforestation movement can improve the capacity of water and soil conservation markedly. Man-planted broad-leaved forests can conserve water resources as 1. 07 as man-planted Coniferous Forest. It can keep water well and reduce splash erosion well. |
