Study On Relationship Between The Plant Community And Environmental Factors In Sphagnum Hummock Microbiotope Of Jinchuan Peatland

Sphagnum hummock originates from the accumulation of dead Sphagnum plants with the characteristic of high acidity and low nutrition. Nine communities and Sphagnum dunes in Jinchuan peatland are investigated in July, August and September monthly in 2006 in order to study the relationship between communities on Sphagnum dunes and environment surrounding. Water samples were also collected in different sites during the field investigation. Data about the abundance of ammonium nitrogen, nitric nitrogen,available nitrogen, available phosphorus,available potassium, available calcium, available magnesium and pH value of water samples were obtained by laboratory experiments. SPSS software is used to analyze the relationship between plant communities and environment factors. All conclusions are as following:(1) From July to September,as the plant selectively absorbe mineralnutrition, available magnesium decreases gradually, nitric nitrogen and available phosphorus decreases at first , and then increases, ammonium nitrogen and available potassium increases gradually, pH value and available calcium increases at first, and then decreases.Available phosphorus, available calcium content correlate weakly with the other factors, while the pH value, available nitrogen, ammonium nitrogen, nitric nitrogen,available potassium and available magnesium correlate strongly with each other. So we infer that the primary recharge source of available phosphorus and available calcium is probably not from the plant decays but ground water. The height of Sphagnum dune, pH value and available mineral nutrition are positive correlation but the radius of Sphagnum dune is negative correlation.(2) Principal component analysis is applied to analyze the data of environmental factors which influence the plants community. The sequence according to their score is as follows: available phosphorus, Sphagnum hummock height, available magnesium, available potassium, pH value, Sphagnum hummock radius, available nitrogen, available calcium, ammonium nitrogen, nitric nitrogen.(3) The condition of high acidity and low nutrition of Sphagnum hummock of is favorable for the growth of Lonicera caeurulea var. deulis, Ledum palustre var. angustum, Oxycoccus quadripetalus Gilib, Jancus effuses, Sphagnum cymbifolium Ehrh, Sphagnum magellunicum Brid. While high acidity and low nutrition limite the growth and development of Betula ovalifolia Rupr, Phragmites australis Trin, Carex schmidtii Meinsh, Thelypteris palustris (Salisb) Schott, Menyanthes trifoliate, Caltha palustris Linn.The top of decay Sphagnum hummock is fit the growth of Aulacomnium palustre (Hedw) Schwaegr, so moisture and mineralnutrition are important factors which influence its growth. Further research on the relationship between Sanquisorpa parviflora Takeda, Ssussurea amurensis Turcz and environmental factors is needed.Quantitative studying on the relationship between the plant community and environmental factors will settle the foundation for the further study and will provide theoretical basis for the restoration of wetland.