Sixteen different vegetation types of grassland and shrubland were selected to study the component and diversity of plant species of riparian plant communities along main channel in the Three-Gorges areas. Species ric...Sixteen different vegetation types of grassland and shrubland were selected to study the component and diversity of plant species of riparian plant communities along main channel in the Three-Gorges areas. Species richness (s), Simpson index (D), and Shannon-Weiner index (H) were used to study the biodiversity and the hierarchical classification was carried out by the methods of TWINSPAN and DCA ordination. The results showed that the components of flora were complex and dominated by the temperate type in the riparian plant communities. Species diversity was not different between the communities, but Shannon-Weiner indexes of different layers in some grassland were significantly different. TWINSPAN and DCA indicated that riparian plant communities distributed along the gradient of moisture.展开更多
The eco-environment and the condition of economic development in the Three Gorges area were evaluated with emergy indices calculated with the statistic data of the years from 1997 to 2005. The rising environmental loa...The eco-environment and the condition of economic development in the Three Gorges area were evaluated with emergy indices calculated with the statistic data of the years from 1997 to 2005. The rising environmental loading ratio indicates an increasing pressure of economic activities on the environment and the economic development achieved at the cost of over-exploitation of resources and environment deterioration. The net emergy yield ratio implies that the economic system of this area was a self-contained, resource-export-oriented type at a relatively low level of technology. The emergy sustainability index of about 6 implies the economy of this area was under developed but had a potential to grow. According to the results of the emergy analysis, circular economy should be taken as the economic model of this region's development. This economic system should be water-resource-oriented and more open, make combined use of local and extraneous resources, and have an updated systematic structure with emphasis on emergy recirculation.展开更多
基金This study was supported by the Chinese Academy of Sciences (A grant KZCX2-406) the National Natural Science Foundation of China (NSFC39970123) and Changbai Mountain Open Research Station.
文摘Sixteen different vegetation types of grassland and shrubland were selected to study the component and diversity of plant species of riparian plant communities along main channel in the Three-Gorges areas. Species richness (s), Simpson index (D), and Shannon-Weiner index (H) were used to study the biodiversity and the hierarchical classification was carried out by the methods of TWINSPAN and DCA ordination. The results showed that the components of flora were complex and dominated by the temperate type in the riparian plant communities. Species diversity was not different between the communities, but Shannon-Weiner indexes of different layers in some grassland were significantly different. TWINSPAN and DCA indicated that riparian plant communities distributed along the gradient of moisture.
文摘The eco-environment and the condition of economic development in the Three Gorges area were evaluated with emergy indices calculated with the statistic data of the years from 1997 to 2005. The rising environmental loading ratio indicates an increasing pressure of economic activities on the environment and the economic development achieved at the cost of over-exploitation of resources and environment deterioration. The net emergy yield ratio implies that the economic system of this area was a self-contained, resource-export-oriented type at a relatively low level of technology. The emergy sustainability index of about 6 implies the economy of this area was under developed but had a potential to grow. According to the results of the emergy analysis, circular economy should be taken as the economic model of this region's development. This economic system should be water-resource-oriented and more open, make combined use of local and extraneous resources, and have an updated systematic structure with emphasis on emergy recirculation.