Research On Dynamic Change Of Soil Physical Property And The Value Of Water Conservation In Guangxi Ecological Forest

This study focuses on the ecological forest in Guangxi, through the soil sampling data from 2005 to 2014 years, analysis the change rule of different forest soil physical properties, master different forest function of water conservation, and to evaluate the value of main forest function of water conservation forests. The results show that:(1) To distant river source, river-banks, large reservoirs and national nature reserve, the autonomous region public ecological forest as the research object, it is concluded that public ecological forest soil physical property as follows:① The soil density of river source is about 1.16 g.cm-3 to 1.25 g.cm-3; The soil density of river-bank is aboutl.17 g.cm-3 to 1.31 g.cm-3;The soil density of large reservoirs is about 1.27g.cm-3 to 1.35 g.cm-3;The soil density of national nature reserve is about 1.16 g.cm-3 to 1.25 g.cm-3, Different ecological niches of different forest types of soil bulk density with time appear regularly to increase after the decrease trend.②The porosity of the soil of river source are between51.43% to 54.88%; The porosity of the river Banks are between 45.13% to 49.91%; The porosity of the soil of large reservoirs are between 49.43% to 51%; The porosity of the soil of national nature reserve are between 44.8% to 56.35%. Different ecological niches of different forest types’soil porosity increasing by the increase of time first.(2) Different forest maximum water capacity and capillary moisture capacity size order is the moso bamboo forest stone mountain> shrub> broad-leaved forest> coniferous forest, soil water holding capacity of the gap with different degree of density and root distribution of tree roots in the soil layer.(3)To evaluate the main forest water conservation value of ecological forest, it is concluded that:in 2014, Guangxi ecological forest stand water conservation value of 162.4 billion yuan, mainly water conservation value is 34000 RMB per unit area, hm 2, water conservation value per unit area of broad-leaved forest> moso bamboo forest> stone mountain coniferous forest> shrub.