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In this thesis, Hunan in conjunction with the first generation of Chinese fir Deforested Lands by different regeneration of transition to second-generation Chinese fir plantation land (12 years born and 20 years of Health), natural update woodland, chestnut woodland, citrus woodland, Miscanthus places the soil organic carbon ( SOC), total nitrogen (TN) content of the vertical distribution of reserves and soil easily oxidized organic carbon (LOC) of the vertical distribution of content, and for the 20-year-old Chinese fir In contrast, calculation of the updated soil carbon pool management index reveals updated woodland soil carbon sequestration abilities of different forest soil carbon pool estimates as well as the sustainable use of soil to provide basic data and scientific basis for human activities. The results show that: the 1,5 update woodland SOC content and density spatial distribution characteristics: (1) update the way woodland SOC content was decreased with soil depth increases the exponential function downward trend (r2 ≥ 0.929); 0 to 75cm soil SOC the average content of descending Sort: the chestnut forest land (14.76 g kg-1) gt; 12-year-old cutting stand (13.54 g · kg-1) gt; 20-year-old cutting stand (12.81g · kg-1) gt ; natural regeneration of forest land (11.50 g · kg-1) gt; gt the Citrus ground (10.73g · kg-1); the Miscanthus places (10.09 g kg-1), and chestnut woodland was significantly higher than the the citrus ground and Miscanthus ground (p lt; 0.05, t test), 12 years, born fir forest land was significantly higher than the Miscanthus manner (p lt; 0.05, t test), while the 20-year Health fir forest land, natural updates between the woodland and Miscanthus ground differences are not significant with (p-gt; 0.05, t test); between the adjacent soil, the 12-year-old cutting stand, the 20-year-old stand in 0 ~ 15cm soil SOC content was significantly higher than the woodland adjacent soil layers (p lt; 0.05), while the other the woodland adjacent soil between SOC content, the differences were not significant (p gt; 0.05). (2) update the way woodland 0 ~ 15,0 ~ 30,0 ~ 45,0 ~ 60,0 ~ 75cm soil the SOC density high to low Sort showed: chestnut woodland gt; 12-year-old stand gt; 20 years old stand gt; the Miscanthus manner gt; natural update woodland gt; citrus woodland. Compared with the first generation 22 years born fir forest to logging when the SOC density of 0 ~ 60cm soil depth, cutting stand shift for 20 years born fir forest land, 12 years born fir forest land, natural update woodland, chestnut woodland, citrus woodland and Miscanthus ground after, woodland SOC density in lower average annual decrease were 2.837,2.666,3.207,2.201,3.565 and 3.278t · hm-2 · a-1, the average annual reduction rate of 1.769%, respectively, 1.666%, 2.000 %, 1.373%, 2.223% and 2.044%. 2,5 update the way woodland soil LOC content space distribution: (1) woodland soil LOC content generally declines linearly with the increase of soil depth (R2 ≥ 0.731) are in the 0-75cm depth the LOC average content 1.100 ~ 1.800g · kg-1, high to low Sort by: natural regeneration of woodland (1.713g · kg-1) gt; 20-year-old cutting stand (1.625g · kg-1) gt; 12-year-old cutting stand (1.406 g · kg-1) gt; the Miscanthus places (1.314g · kg-1) gt; citrus woodland (1.260g · kg-1) gt; chestnut woodland (1.119g · kg-1). (2) update the way woodland soil LOC allocation proportion with the increase of soil depth trends. Fir forest, the natural regeneration of woodland, chestnut woodland, citrus woodland showed decreased and then increased with soil depth, Miscanthus decline compared to the first rise. 0 ~ 75cm soil LOC average allocation ratio of 0.07 to 0.15, including cutting stand, natural regeneration of forest land, the citrus woodland, Miscanthus ground are significantly higher than the chestnut woodland (p lt; 0.05), and 20-year-old cutting stand, natural update woodland were significantly higher than the 12-year-old Chinese fir (p lt; 0.05), and the rest of the update Means twenty-two were no significant differences (p gt; 0.05). The 3,5 update the way woodland soil TN content and density spatial distribution of the differences: (1) the overall content of soil TN on with the increase of soil depth declines linearly (R2 ≥ 0.701) in the size of the average content of 0 ~ 75cm soil Sort: chestnut woodland (1.68 g · kg-1) gt; the Miscanthus land of the 12-year-old cutting stand (1.57 g · kg-1) gt; 20-year-old cutting stand (1.47 g · kg-1) gt; (1.40g · kg -1) gt; natural regeneration of forest land (1.38 g · kg-1) gt; citrus woodland (1.31 g · kg-1) (2) update the way woodland 0-15,0 ~ 30,0 to 45,0 ~ 60,0 ~ 75cm soil TN-density high to low Sort showed: chestnut woodland gt; 12-year-old stand gt; Miscanthus to gt; natural update woodland gt; 20-year-old stand gt; citrus woodland. 4, the slope of the face of the the Chinese fir SOC content has some influence, but as planting the number of years of growth and change; With growth of fir Age, left (east) slope fir forest contribution of deep soil organic carbon density right (west) slope. 5, the sloping face the cutting stand LOC content along with the growth of the planted years and change. , The sloping face the cutting stand TN content with the growth of the planted years changed; soil TN accumulation rate is greater than the slope of the left (east) right (west) slope, with the growth of the number of years of Chinese fir planted, left The slope soil TN density (East) over right (west) slope. 7 to 20-year-old stand as the control, updated way the woodland soil management index exists heterogeneity. Natural regeneration of the forest soil carbon pool activity (L) the carbon pool activity index (LI), carbon pool management index (CMI) than the control, respectively 14.12%, 21.60%, 18.33%; 12-year-old Chinese fir, mandarin orange woodland, chestnut woodland soil L, LI, CMI were lower than that of the control ground; the Miscanthus soil L, LI higher than the control ground CMI control ground than citrus woodland; 12-year-old cutting stand, chestnut woodland soil carbon pool index (CPI) than in the control places increased by 15.60%, 23.30%, and natural regeneration of woodland, citrus woodland, Miscanthus ground than in the control ground were reduced by 0.50%, 11.50%, 17.40%. 8,5 kinds Update Means SOC, TN, LOC, the CMI and soil bulk density showed a negative linear correlation, with soil moisture content, pH correlation apparent regularity.
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