Study On The Species Diversity And Niche Of Dominant Population In Coastal Vegation Of Guanmen River

In headwater of Liao River, the property of the river and vegetation stability will directly affect the ecological environment of downstream, so its influence is significant for plant diversity, prevention soil conservation and ecological balance with study on the diversity of the Liao River headwater of vegetation at shore. Based on field investigation in Guanmen River, through calculating the diversity index (Shannon-Wiener diversity index, Pielou evenness index, Patrick richness index and Simpson dominance index), niche index (niche breadth and overlap) and analysis crossing shoreline the changes of species diversity in estuary and along shoreline the changes of coastal vegetation species diversity and niche of dominant population in Guanmen River. This research can provide the support to protection vegetation, soil and water conservation and ecological balance. The results showed:① Crossing shoreline, the community diversity, richness and evenness of the Lemna minor community, Sparaganium coreanum Scirpus tabernaemontani community, Pofygonum hydropiper Arthraxon hispidus Echinochloa crusgalli community and Quercus mongolica Juglans mandshurica community are increased in estuary. The community of dominance decreased first and then increased. The community of lowest diversity is Lemna minor community.② The community of the diversity, richness and evenness of Echinochloa crusgalli community, Sorbaria sorbifolia Agriminia community, Sorbaria sorbifolia Weeds community and Juglans mandshurica Quercus mongolica community are decreased first and then increased. But the dominance increased first and then decreased. The lowest diversity are Sorbaria sorbifolia Agrimonia pilosa community and Sorbaria sorbifolia Weeds community.③ The tree niche breadths of Juglans mandshurica(0.467), Quercus mongolica(0.345) and Acer mono(0.301) are largest. But from the family, the niche breadth of Maple family is the largest. The shrub niche breadth of Sorbaria sorbifolia is largest. In suspect of the herb niche breadths, the niche values of Cacalia hastate(0.477), Agrimonia pilosa(0.440) and Glycine soja (0.445) are high. The herb niche breadth of Sparaganium coreanum(0.395), Scirpus tabernaemontani (0.395), Polygonum hydropiper(0.384), Lemna minor(0.311) and Echinochloa crusgalli(0.304) are lower than them. The herb niche breadth of Arthraxon hispidus(0.288), Plantago major(0.258), Setaria viridis(0.235), Phragmites australis(0.244), Leymus chinensis(0.242) and Typha orientalis(0.223) are lower also.④ The niche overlap values of all plant are not very high in coastal vegation of Guanmen River. The tree niche overlap of the Juglans mandshurica and Acer mono(0.142) the Juglans mandshurica and Quercus mongolica(0.108) are large. In the view of the family, the overlap of Maple family is largest. The shrub niche overlap of the Sorbaria sorbifolia and the Rubus corchoriflius(0.018) are large. The herb niche overlap of Sparaganium coreanum and Scirpus tabernaemontani(0.292), Sparaganium coreanum and Lemna minor(0.176), Lemna minor and Polygonum hydropiper and Arthraxon hispidus (0.174) are large. The herb niche overlap of Scirpus tabernaemontani(0.169), Polygonum hydropiper and Echinochloa crusgalli(0.153), Arthraxon hispidus and Echinochloa crusgalli(0.153) are lower than them.Integrated the above conclusion, the middle part of Liao River headwater and it’s the banks close to water the plant species diversity is low. Therefore, to strengthening protection of the middle part of the river headwater and the part near water is the measure for protection vegetation, soil and water conservation and ecological balance.