Research on the forest soil water in the hilly area at different density of Pinus tabulaeformis Carr.in Northern Hebei

In order to evaluate the water conservation function level of the harf-mature forest plantation of Pinus tabulaeformis Carr.in the northern Hebei mountains,the soil moisture physical characteristics of different stand density of 30A Pinus tabulaeformis in the Beigou Forest Farm are studied.On the basis of total soil capillary water capacity,maximum storage capacity of Pinus tabulaeformis,the forest soil water content was probed.The results showed that:(1) Among the 5 densities of Pinus tabulaeformis stand,there was weaker capillary porosity change law,with non capillary porosity of 1.7%~5.6%,which increased with the increase of the density,and total soil porosity of 39.3%~49.1%.(2) The maximum soil storage capacity was 2 853~3 112 t/hm2,and the greater density,the stronger soil water storage ability was.When the density reached more than 1 200 plant/hm2 plants,there exists a trend of slow increase.