The atmospheric CH4 oxidation rate of peat bog soil from the Zoige Plateau was 0.97~1.69ng/(g·h), and decreased with increasing of the soil depth, but the discharged rate of CH4 from peat soil was 0.37~0.61ng/(g·h).
The main results showed that vertically ,the roots concentrated at the 80～100cm soil zone where the amount of roots accounted for 38.75% of the total, but the amount of roots below 100cm soil zone sharply decreased, and the root length density varied with the soil depth in a exponent curve;
(2) Soil porosity and soil non-capillary porosity tended to decrease with the increasing of soil depth,but on the contrary,in chestnut intercropping mode they tended to increase with the increasing of soil depth.
It suggested that there were significant effects of season, plantation and soil depth on soil fauna (P<0.01, three-way-ANOVA). Soil fauna were conspicuously abundant in autumn (P<0.05, DMRT), but conspicuously succinct in summer (P<0.05, DMRT).
pH in the 10 ~ 50 cm soil depth was decreased by 0.02 ~ 0.83 unit, and soil exchangeable Al was increased by 22.45 % ~ 34.66 % in 10 mmol/L citric、malic and oxalic acid treatments, respectively, compared with simulated acid rain treatment.
pH in the 10 ~ 50 cm soil depth was decreased by about 0.1 unit, and soil exchangeable Al was increased by 6.99% ~ 12.82 % in 100 μmol/L citric、malic and oxalic acid treatments, respectively, compared with simulated acid rain treatment.
The results showed that pH in the 0 ~ 10 cm soil depth was decreased by 0.27, 0.44 and 0.08, 0.18, and soil exchangeable Al was increased by 4.43% and 2.38%, respectively, after leached with pH 3.5 and pH 4.5 simulated acid rain, compared with deionised water check, while pH in the10 ~ 50 cm soil depth was not changed significantly.
pH in the 0 ~ 10 cm soil depth was higher within 0.3 unit, and soil exchangeable Al was lower 0.08 ~ 0.75 cmol/kg in the citric, malic and oxalic acid treatments than that of in the simulated acid rain treatment, respectively.
Soil water contents in the two systems were both increasing with the increase of soil depth, but their difference was great. The soil water content in complex system stably ranged from 7.59% to 23.79%, while that in monoculture system varied greatly and ranged from 4.73% to 49.72%.