Chin J Plan Ecolo ›› 1996, Vol. 20 ›› Issue (5): 449-459.

• Research Articles • Previous Articles     Next Articles

Research on the Restoring Succession of the Degenerated Grassland in Inner Mongolia I. Basic Characteristics and Driving Force for Restoration of the Degenerated Grassland

Wang Wei, Liu Zhong-ling, Hao Dun-yuan, Liang Cun-zhu   

  • Published:1996-05-10
  • Contact: Wang Wei

Abstract: A grazing-induced degenerated Artemisia frigida community has been monitored till 1993 since it was fenced in 1983 in the middle reaches of the Xilin River. The vegetation was measured by 10~20 quadrats of 1m2 once per 15 days during the plant growing season from May to September each year. The species standing crops, density, height, water content, and their flowering stem number were recorded. The similar monitoring were simultaneously conducted in the well protected communities dominated by Leymus chinensis and Stipa grandis. The dynamics of spatial distribution pattern of plant population has also been monitored with improved method of quadrat variance. Based on a comparative analysis of these data, the community features were summarised and the driving force for restoration was discussed. The results are as follows: 1. The degenerated Artemisia frigida community is in a stable state corresponding to a certain grazing intensity. Degeneration degree depend on the grazing intensity. 2. The species composition of the degenerated A. frigida community has no significant difference from that of primary plant community dominated by L. chinensis. The grazing disturbance has a big effects on the proportion of plant population in community, but no much effects on the species richness for the succession series between A. frigida and L. chinensis communities. 3. The spatial hetterogeneity is low in degenerated community, and will increase with the restoring succession due to the patches of some populations’ expansion. 4. The species-biomass relationships in degenerated community and in primary community fits to a log-normal distribution model. The restoration succession fits to a broken-stick distribution model. 5. A significant character of the degenerated grassland is the low productivity. The productivity is only 1/3 of the primary community, and palatable forage proportion is only 50 % ~ 70 % of the primary community, so the usable productivity decreased to only 30% of that of primary community. 6. The plant colonising ability and the relative surplus resource in the degenerated community is the driving force for its restoration