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Fir endemic species of fast growing and excellent material. Until 2004, the Chinese fir area of ??9,213,500 ha, accounting for 30.4% of the total plantation area, occupies an important position in the structure of China's forest resources and alleviate the pressure on China's economic development is the growth in demand for timber and to support the protection of natural forests etc. plays an important role in the implementation of major ecological engineering. However, the traditional management of Chinese fir plantation woodland lasting ability to maintain the productivity of domestic forest circles widespread concern one. Clearcutting, burning and site preparation is an important measure of the operation and utilization of Chinese fir plantation. Order to study the short-term impact of these measures on Chinese fir plantation soil, as before and after harvesting, before and after the slash burning, site preparation and reforestation chronological points 0-15 cm ,15-30 cm two layers of soil samples were collected. The test results show that: to all silvicultural measures available N and 0-15 cm layer pH, organic carbon and organic matter has a significant effect. pH showed a downward trend after the implementation of various measures. To retain residues increase soil organic carbon after harvesting, controlled burning has led to the reduction of the organic carbon content. Make soil redistribution and restored to the level before the harvesting of the organic carbon and ash after burning and mixing of soil preparation. Available N content after logging and slash burning significantly reduced, but to reduce the amount of compensation but soil preparation after. Silvicultural practices on soil bulk density, total N, total P, available P content had no significant effect. The two layers of 0-15 cm and 15-30 cm soil K and Mg content were significantly decreased after harvesting. Burning and before and after the 0-15 cm K content increased, but decreased significantly after site preparation. Controlled burning and site preparation on full-Mg was not significant. In the artificial real Shiying Lin measures intended to avoid the rainy season the case in this study did not reach past that the fir forest soil logging, slash burning, silvicultural measures have led to an increase in bulk density, organic carbon, organic matter, total N and total P is reduced findings. Within 1 a pH showed an increasing trend after planting; bulk density and organic matter and organic carbon, total N, total P, total K and Mg content in the first few months after afforestation have increased, but the rainy season of leaching have some degree of impact, it decreased in varying degrees, but had no significant effect on the total P content of this study element. The logging residue contains a lot of nutrients, is an important source of the woodland soil organic matter and nutrient elements, is an important substance in the nutrient cycling of forest ecosystems library. From logging residue decomposition and nutrient release angle to study the contribution of logging residue on the soil nutrient, and then to explore fir artificial forests sustainable development of operational problems. The results show that: the logging slash after the clear-cutting of Chinese fir plantation bio about 65.91t.hm-2, N, P, K, Ca, total nutrients Mg5 elements 1 632.37 kg.hm-2. The logging slash branches, leaves, fruit and skin such as biomass and nutrient content of different proportion to sprig biomass attributable to the largest proportion of the nutrient content share of logging slash total nutrient proportion largest. In the decomposition test different components of the decomposition rate of leaf fastest, followed by twigs and leather; big sticks and fruit of the decomposition rate of the slowest. Generally faster decomposition rate and the various components in the first 122 d to 246 d period (late May to late September). Exponential regression equation residual logging slash the rate of decomposition time simulation results showed that the leaf decomposition 50% of the required 17.99 a, decomposition of 95% of the required 25.88 a; big sticks and fruit decompose 50%, respectively, required 36.10 a and 36.16 a decomposition 95 %, respectively, required 51.90 a 51.93 a; the logging residue decomposition of 50% of the required 24.07 a, decomposition of 95% of the required 34.58 a. The end of this test, i.e. the decomposition of 402 d, logging residue there are a large number of C, P, Ca and Mg is freed for 3996.14kg.hm-2, the total amount of the four elements release. The logging residues nutrient release rate from fast to slow order P gt; Mg gt; Ca gt; C and sprig is the main source; N elements in logging slash accumulation, although sprig small amount of released. N accumulation, leaf is the main exchange, followed by skin. Logging residues in the C / N, C / P between the different components of a larger range, and the range of variation of the N / P is smaller.
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