Spatial Patterns Of Soil Nutrients And Productivity Of Phyllostachys Pubescens Forest In Anhui

Phyllostachys pubescens is an important economic bamboo species. Bamboo with its enormous ecological and economic value is very adaptable. At present, the productivity of bamboo forest began to decline due to unreasonable management. Therefore, in order to sustain the high yield of the bamboo forest and to provide a theoretical basis and reasonable measures for management of Moso bamboo forest, a systematic study on soil nutrients and stand productivity of the bamboo forests was conducted at the the main producing area in Anhui. The results are as follows.(1) The order of the average diameter of the bamboo culms at the different areas is Taiping (10.81cm)> Xiaokeng (10.52cm)> Huoshan (10.09cm)> JingXian (9.91cm)> Yeshan (9.53cm)> Guangde (9.04cm). The order of the bamboo density index is Taiping (0.34)> Xiaokeng (0.31)> Jingxian (0.30)> Guangde (0.27)> Yeshan (0.24) Huoshan (0.21). The order of the stand biomass is Taiping (94.69t·hm-2)> Xiaokeng (80.84t·hm-2)> Jingxian (78.19t·hm-2)> Guangde (73.75t·hm-2)> Yeshan (70.81t·hm-2)> Huoshan (54.7t·hm-2). Generally the stand boimass is higher in the southern mountane area than in the the Dabieshan area. Various regions of bamboo each part of The biomass partition for the different areas demonstrated the similar patterns as: bamboo culm> bamboo branch> bamboo root> bamboo leaves.(2) The order of the soil moisture content in the bamboo forest is Taiping> Jingxian> Yeshan> Guangde> Xiaokeng> Huoshan. The order of the average soil pH is Huoshan> Jingxian> Guangde> Yeshan> Taiping> Xiaokeng. The order of the soil bulk density is Taiping> Yeshan> Guangde> Xiaokeng> Huoshan> Jingxian.The soil nutrients varied greatly amongst the different sites. In the0-10cm layer, the total N concentrations were from1.96(Huoshan) to4.73g·kg-1(Taiping); total P from0.54(Xiaokeng) to2.52g·kg-1(Guangde); total K from1.38(Taiping) to3.38g·kg-1(Huoshan); soil organic matter from28.39(Huoshan) to48.19g·kg-1(Taiping); available N from59.55(Jingxian) to82.71mg·kg-1(Huoshan).In the10-30cm layer, soil nutrients also varied greatly. The mean concentrations of total N ranged from2.51(Guangde) to4.35g·kg-1(Taiping), total P from0.47(Xiaokeng) to2.51g·kg-1(Guangde); total K from1.65(Guangde) to4.19g·kg-1(Huoshan); soil organic matter from22.60(Huoshan) to35.25g·kg-1(Jingxian); available N from53.61(Jingxian) to80.43mg·kg-1(Huoshan).The concentrations of total N, organic matter, available N were all gradually decreased with soil depth. The N concentration at the different sites varied widely. The total K concentration was all lower in0-10cm soil layer than in10-30cm layer. In all the three layers of soil, the concentration of organic matter was the lowest at Dabieshan. However, the concentration of available N was highest this area. The lowest concentration of available N was found in Jingxian.The result from the correlation analysis showed that the stand biomass were significantly and positively related to the soil total N, organic matter, both of which showed a extremely significant and positive correlation. The average diameter of the culm was significantly and positively correlated with soil organic matter and available nitrogen. The satnd density index was significantly and positively related to the soilo total nitrogen, organic matter and available phosphorus.In the main areas of bamboo-production in Anhui, the total N, total P, total K, organic matter, available P and available N was the main nutrients in soil. The result from the principal component analysis showed the total N, total P, organic matter and available P were the main features of the soil nutrient factors, of which the total P and organic matter had total contribution of48.28%. This indicates that total P and organic matter became the important control of soil nutrient factors. The total N (contribution of19.75%) and available P (13.53%) bacame the secondary factor in controlling the productivity of bamboo forests in Anhui.