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| Evaluation to composing, structure and function for soil and water conservation of vegetation in rehabilitated lands in upper reach of the Yellow River |
| Hu Jianzhong, Zheng Jiali, Zhang Chunxia |
| College of Soil and Water Conservation,Beijing Forestry University;Key Laboratory of Soil and Water Conservation and Desertification Combating of the Ministry of Education,100083,Beijing,China |
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Abstract For the severe situation of eco-unbalance in the upper reaches of the Yellow River, the study of function for soil and water conservation in rehabilitated lands not only has the theoretical values, but has the urgent need for practice. The more the species and layers, the higher the function of vegetation. The research in the high mountains of the upper reaches of the Yellow River, shows that the high species richness appears in the middle stage of vegetation succession with more plant layers (usually 3～5 layers) and complex species and genes, and result in more rain reception and good eco-functions. In the implement of the project of Conversion of Cropland to Forest and Grassland, more attention should be paid to rehabilitate mixed conifer (mainly Picea crassifolia)and broad leaved trees in the middle stage of succession than such climax communities. As the vegetations grow, their structures and functions increase gradually. Some artificial vegetation types after 20 odd years in the rehabilitated lands have more bio-diversity, complex vertical layers of community, with so good eco-functions that even surpassing some of native vegetation, and approaching to the best one of eco-function in the areas, namely, 50 odd years native mixed Picea crassifolia with broad leaved trees. In the process of PCCFG, it is pressing and feasible to realize the whole function of artificial vegetation in the rehabilitated lands by means of imitating native vegetation structure for restoration of mixed and complicated vegetation types.
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Received: 22 August 2004
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