The Vegetation Restoration and Reconstruction of Different Types of Degraded Barren Ecosystems in Jiangxi

27 Mar The Vegetation Restoration and Reconstruction of Different Types of Degraded Barren Ecosystems in Jiangxi

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Abstract

English Abstract

To restore vegetation on five major types of barren hills in Jiangxi Province, trials were set up in 1990 and were carefully monitored afterwards. Both short and long term feasibility were taken into account by selecting high valued and hardy species to ensure the success of the re-vegetation processes on these barren hills. Based on the type of the barren hill and local weather pattern, species of trees, shrubs, grasses and their combinations were carefully selected to study suitability of the plant. According to the local conditions and goals, various management skills and practices with either the cross-over or the randomized block design were conducted. The survival rates, growth rates and degree of vegetative coverage were recorded annually. In 1994, economic analysis and a more detailed survey were conducted to record biomass, microclimate, soil properties and root growth. The results indicated that simultaneous introduction of a mixture of selected conifers, broadleaf trees, shrubs and grass improved soil properties and erosion control significantly and stimulated further vegetative growth. Eminent pioneer trees and grasses are: Pinus massoniana, Platycladus orientalis, Liquidambar fomosana, Schima superba and Gardenia jasminoides, Lespedeza spp. On limestone barren hills, combinations of Platycladus orientalis and Firmiana simplex, Toona sinensis and Amorpha fruticosa, Alnus cremastogyna and Platycladus orientalis as well as Cornus macrophylla and Amorpha fruticosa gave satisfactory results. Mixtures of Pinus massoniana spp. and Lespedeza spp. with Paspalum wettsteimit as well as Pinus elliottii and Liquidambar fomosana with Digitaria spp. produced the best results on severely eroded barren hills in south and east side of the province. Root hormone to stimulate root growth, sapling transplantation with container seedling to boost survival rates, fertilizer supplement to provide proper nutrients for growth, species selection to elevate survival rate as well as economic return when harvest and high population density to sustain colonial plants were important factors in vegetative restoration. On the steep slopes in central Jiangxi, soil and water conservation practices such as building terraces and water-retaining pits were applied to ensure the initial establishment of the introduced vegetation. Due to the interference from human activities, severe soil erosion, infertile soil and low survival rate for tree seedling, good management skills developed for various local situations in this study are needed to bring vegetation back to these barren hills in Jiangxi