| Controlled burning is a common way of silvicultural forest management, is currently cleaning up deforested simple, rapid and cost-effective means of one, in the afforestation has been widely used in the burning logging residues and ground vegetation composition also will cause water and soil and nutrient loss, thereby affecting the growth of trees. Shading network coverage is improving a negative impact on the process of refining the mountain forest soil ecosystem processes? Unclear. Therefore, in order to understand shade net treatments on soil ecological processes after controlled burning, the use of site control experiments, comparative study of the shading rate of 100% shade net cover ((SC1) and 85% of the sun shading network coverage (SC0.85) treatment on controlled burning and non-burning mountain of Young Forests of new soil carbon dynamics of nitrogen and phosphorus in order to provide a scientific basis for sustainable operation and management of the Yangtze River upstream of Masson Pine Plantation findings as follows:(1) Significantly increased shading network coverage covering 60 d refining mountains and soil organic carbon content, covering 60 d, burning and soil organic carbon was significantly lower than SC1 none burning, slash burning and covering 150 d, SC1 and SC0.850-30 cm significant increase of 79%-139% and 106%-172% of soil organic carbon content. With respect to controlled burning, no slash and covering 300 d, SC1 for 0-30 cm soil organic carbon significantly increase 31%-53%,480 d when SC1 and SCo.85 increase 0-30 cm soil organic carbon were 24%-28% and 24%-26%. In refining the mountains and covering 60 d, SC1 and SCo.85 for 0-30 cm microbial biomass carbon content was increased by 45%-78% and 17%-29%, no slash and mulch 60 d and 150 d SC1 only 15-30 cm of soil microbial biomass carbon content of 40% and significantly higher 85%. Controlled burning and covering 150 d, SC1 15-30 cm soil layer in addition to outside, SC1 and SC0.85 for 0-15 cm soil microbial biomass carbon significantly reduced the proportion of 74%-137% and 77%-152%, None burning and covering 150 d, SCi and SC0.85 for 0-15 cm soil microbial biomass carbon rates were significantly reduced by 32%-33% and 22%-44%.(2) Reduce the burning and soil nitrogen content showed a trend, but it can significantly increase the content covered 60 d and 150 d ammonium and nitrate. Shade net cover can be improved to some extent controlled burning to reduce the tendency of soil nitrogen content, and the significant increase in ammonium and nitrate content in soil under controlled burning environment, refining and fertilizer mountains covered within 60 d and 150 d obvious effect. Relative to the SC1, SC0.85 can be more effective in promoting increased soil mineral nitrogen. Controlled burning significantly reduced and covering 60 d,150 d and 300 d soil microbial biomass nitrogen content, were reduced by 21%-63%,63%-108%,52%-97%. Shade can significantly increase network coverage and microbial biomass burning and the nitrogen content is not burning and environment, but it does not completely change the negative effects of controlled burning on soil microbial biomass. Compared SC1, SCo.85 more effective in promoting increased microbial biomass nitrogen, might be more effective in promoting the recovery of soil microbial community.(3) Significantly reduced refining mountains covering 60 d,300 d and soil total phosphorus and available phosphorus content of 480 d, in refining the mountains and covering 60 d,150 d,300 d and 480 d, SC1 and SC0.85 for refining controlled burning slash total phosphorus content had no significant effect, no slash and covering 60 d, SC1 significantly increased total phosphorus content of 72%-156% coverage at no slash and 150 d SC1 and SCo.85 significantly reduced 5-15 cm soil total phosphorus content of 45% and 33%; no slash and covering 300 d SC1 and SC0.85 were not significantly increased phosphorus burning and slash 50%-113% and 42%-180%. Controlled burning showed decreased soil phosphorus activation coefficient, covering 150 d, SC0.85 significantly reduce the burning and slash 0-5 cm and 15-30 cm soil layer of soil phosphorus activity value of 52% and 88%. SC1 for none burning 15-30 cm soil layer of phosphorus activity significantly decreased 83%.(4) Controlled burning ratio significantly affect carbon and nitrogen phosphorus ratio of soil carbon and nitrogen than those without, controlled burning and covering 150 d, SC1 and SC0.85 significantly improve the 0-30 cm soil nitrogen ratio, which increased the value of 27%-165% and 37%-148%, No slash and covering 480 d, SC1 and SC0.85 significantly improves the 0-30 cm soil carbon and nitrogen ratio of 17%-36% and 21%-42%. SC0.85 cover 60 d,150 d and 300 d for controlled burning slash carbon-phosphorus ratio of 0-30 cm a significant effect, while SC1 and SC0.85 covering 150 d and 480 d for none burning carbon 0-30 cm significant than the effect of phosphorus. SC0.85 covering 60 d for controlled burning slash 0-15 cm nitrogen to phosphorus ratio improved significantly to 49%-53%. Although these results appear in the process and the specific mechanisms still need further research, but for the region and similar Masson pine plantation silviculture provide new ideas and theoretical basis. |
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