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| Investigation of shrub germplasm resources and community successionin Kongtong Mountain,eastern Gansu Province |
| Li Zhencun1, Zhang Feng2 |
| 1. Gansu Bureau of Eco-environment Detection and Supervision, 730020, Lanzhou, China;2. Institute on Soil and Water Conservation, Gansu Province, 730021, Lanzhou, China |
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Abstract In the region of Kongtong Mountain of eastern Gansu Province, there are various and complextypes of plants with seed plants 702 species in 356 genera of 90 families, in which 662 species in 343genera of 88 families are wild type. It is a valuable natural species gene pool. The forest coverage rateincreased from 37.4% in 1996 to 45.8% in 2011, and shrub land area increased from 3216hm21996 to 3 865hm2 in 2011. Accompanying with the shrub land area increasing is the complex successional change of community structure. In order to clarify the structure and community of shrubs and vegetation landscape change of Kongtong Mountain under different habitat conditions, we conducted a resource scensus in the Kongtong Mountain forest region with rich shrub resources banned for many years. Theregion was divided into four different habitat types according to the aspect and location, i. e. , sunny,semi-sunny, semi-shady and shady. According to the detailed investigation of habitat types, a basesurvey line was selected along each of the channels, slope moldings, ridges and other typical geomorphology. Finally, 13 sample lines and 115 determination sections were set. We systematicallyanalyzed the relationship among shrub community, ecological environment, shrub communitycomposition, structure and community succession in the Kongtong Mountain under various ecologicalconditions. The results showed that there are a total of 142 species of shrub, sub-shrub and liana plants,belonging to 39 families and 74 genera. Except for one family, one genus and two species that belong to the gymnosperms, they are all angiosperms with most species belonging to North China Flora. Various shrubspecies have their certain spatial distribution features. There is a certain hierarchy along the verticaldistribution that can be divided into three elevation zones: 1 393-1 496 m, 1 796-1 946 m and 1 946-2046 m. Shrub community compositions are different under four slope conditions with 12 main species distributed in sunny slopes and Sophora davidiias the constructive species, 14 main tree species in semi-sunny slopes and the sea buckthorn as constructive species,12 main tree species in semi-shady slopes, and 15 main tree species in shady slopes and the ostryopsis as constructive species. In the case without disturbance, the succession of shrub community began from the bare wasteland during the period, and hasprobably experienced natural grassland, mixed shrub and grass, shrub community, sub-shrub community and the ultimate succession of arbor community. It is a complicated system for the development andutilization of shrub resources in Kongtong Mountain and therefore we must strengthen the protection anddevelopment of shrub resources and plan utilization, vigorously protect the suitable shrubs such asSophoradavidii, sea buckthorn,Prunus davidiana, caragana,Ostryopsisand so on, expand the scale ofresources, and ensure the sustainable development and succession of shrub community in the region.
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Received: 07 March 2015
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