Li S.-F.,Chinese Academy of Forestry |
Li S.-F.,The Puer Forest Eco system Research Station |
Su J.-R.,Chinese Academy of Forestry |
Su J.-R.,The Puer Forest Eco system Research Station |
And 8 more authors.
Forest Research | Year: 2015
Taking three stand age-class(immature forest, near-mature forest and over-mature forest) of Pinus kesiya var. langbiannesis plantation and nearby green broad-leaved forest, primary coniferous forest as contrast in Pu'er city, Yunnan province. We discussed that the impacts on afforestation for size and spatial distribution of soil organic carbon and nitrogen stocks of Pinus kesiya var. langbiannesis plantation.The results show that soil organic carbon content, nitrogen content and C:N gradually decreased with increase of soil layer thickness in different forest types. Soil organic carbon and nitrogen content in the over-mature forest were significantly higher than that of other forest types as the soil layer deepen and soil organic carbon and nitrogen content of topsoil in the near-mature foretst is significantly lower than that immature forest and over-mature forest. Tree layer carbon stocks of Pinus kesiya var. langbiannesis plantation increased with stand age development, moreover, tree layer carbon stocks in the over-mature forest was significantly higher than other forest types. Afforestation had no significant effect on soil nitrogen stocks, and the soil organic carbon stocks increased, then decreased and recovered the level of green broad-leaved forest and primary coniferous forest with the stand age development. Simultaneously, soil organic carbon and nitrogen stocks decreased with the increase of soil layers depth(0-60 cm). The relative Change rate of soil organic carbon and nitrogen stock of immature and over-mature forest were higher than near-mature forest with stand age development compared with the green broad-leaved and primary coniferous forest, and the relative change rate of soil organic carbon and nirtrogen stock of near-mature forest had obviously net reduction. Artificial reforestation of priamry coniferous forest can accumulate more soil organic carbon and nitrogen stocks than green broad-leaved forest. there were a significant and extremely significant positive correlation between soil moisture and soil organic carbon stocks in the different soil layer depth. © 2015, Chinese Academy of Forestry. All right reserved.