Soil Properties Responding to Pinus tabulaeformis Forest Thinning in Mountainous Areas, Beijing

摘要

Studied soil physiochemical properties of Pinus tabulaeformis plantations under varying silviculture intensity in shade, slope and thick soil areas in mountain areas of Beijing. The results show that at intensive (50%), medium (45%), weak (33%) thinning intensity compared with the control, (1) soil bulk density was reduced by 7.9, 5.7 and 3.9%, respectively in depth from 0 to 10 cm (layer_0-10) and soil properties in layer_0-10 were better than in depth of 10-20 cm (layer_0-10). (2) Total soil porosity increased by 7.3, 5.4 and 2.9%, respectively; the effects of thinning intensity on soil non-capillary porosity ranked as: weak>medium>intensive>control and the total soil porosity and non-capillary porosity both changed similarly in the two layers. (3) Water infiltration capacity and total soil pondage capacity were enhanced by thinning intensity. (4) Soil organic matter, total Nitrogen and rapidly-available Phosphorus were maximized in the medium thinning plot, while the rapidly-available Potassium was maximized in the intensive intensity plot, demonstrating that medium and intensive thinning can improve the P. tabulaeformis forest soil nutrient level. (5) The effects of thinning intensity on catalase and urease activities ranked as: medium>intensive>control>weak, which revealed that the soil enzyme activity can be improved by forest thinning. In conclusion, to improve soil physiochemical properties of P. tabulaeformis plantation in shade, slope and thick soil areas in mountain areas of Beijing, we prefer intensive thinning management.