| As a serious problem of ecological and environmental degradation, Karst rocky desertification has severely constrained the local social and economic's sustainable development, and has gradually been valued by people. With the development of the vegetation restoration on the Karst rocky desertification, the study on the Karst rocky desertification has been widely taken into account by the ecologists. Biomass is a primary function index of the ecological system, and has important ecological significance, and it is the foundation of the study in energy balance, energy flow, nutrient cycling and other functional processes of ecosystem; while the distribution pattern and accumulation of vegetation nutrient elements are not only the basic characteristics of forest ecosystems, but also the important and indispensable aspects of forest to maintain its structure and founction. Therefore, it can provide important reference data for the vegetation restoration on the Karst rocky desertification to configure a reasonable stand structure and develop an appropriate silvicultural method, to study on the distribution of biomass and nutrients in different vegetation restoration stands in the Karst rocky desertification.In order to study the distribution characteristics of biomass and nutrient elements and the physical-chemical properties of soil in rocky desertification area,5 patterns of vegetation restoration stand were chosen in rocky desertification area in Shaoyang county, Hunan province, by using sample survey design and laboratory analysis methods. The 5 patterns vegetation restoration stand were Platycladus orientalis (Linn.) Franco Pure Forest (POPF), Liquidamba formosana Hance and Platycladus orientalis (Linn.) Franco Mixed Forest (LPMF), Liquidamba formosana Hance Pure Forest (LFMF), Pinus elliottii Pure Forest (PEPF), Pinus elliottii and Liquidamba formosana Hance Mixed Forest (PLMF). We obtained the following achievements:1. In the young stage, the Pinus elliottii grows better than other trees, and had 7.79 cm in average DBH,5.07 m in average hight, and had the largest biomass. The total biomass of the PEPF was 38.66 t·hm-2 which accounted for 91.49% of tree layer, for 6.93% of understory vegetation, for 1.58% of litter. The total biomass of the POPF was 7.20 t·hm-2 which accounted for 51.39% of tree layer, for 39.86% of understory vegetation, for 8.75% of litter. The total biomass of the LFPF was 4.30 t·hm-2 which accounted for 9.30% of tree layer, for 86.51% of understory vegetation, for 4.19% of litter.2. The total biomass of the LPMF was 8.49 t·hm-2 which accounted for 39.11% of tree layer, for 48.76% of understory vegetation, for 12.13% of litter. The total biomass of the PLMF was 9.19 t·hm-2 which accounted for 18.93% of tree layer, for 60.18% of understory vegetation, for 20.89% of litter.3. Through multi-model optimization, we found that the forecasting models of W=a(D2H)b can be used to simulate the biomass of the organs and a single tree of Platycladus orientalis (Linn.) Franco and Pinus elliottii in the period of the early vegetation restoration stand.4. The order of macroelement of the tree in the 5 different patterns of vegetation restoration stand were not the same, which were Ca>N>K>Mg>P in POPF and LFPF and LPMF, N>Ca>K>Mg>P in PEPF and PLMF. This showed that the macroelement N was much more in the Pinus elliottii than in any other plants, as a result, the Pinus elliottii grows faster in the early stage of the vegetation restoration. The content distribution rule of the macroelement in various organs of the vegetation was the leaf with the hightest content of the macroelement except Ca.5. The order of microelement of the tree layer were Fe>Mn>Zn>Pb>Cu>Ni>Cd in POPF and PEPF, Fe>Mn>Zn>Ni>Cu>Pb>Cd in LFPF, and Fe>Mn>Zn>Cu> Pb>Ni>Cd in the other two mixed forest (PLMF and LPMF).6. The order of macroelement of the shrub layer were Ca>N>K>Mg>P in POPF, N>K>Ca>Mg>P in LPMF and PEPF, K>N>Ca>Mg>P in PLMF and LFPF. The distribution rule of the macroelement in the shrub layer was that the aboveground part of nutrient content was higher than the underground part of the nutrient content, but the distribution rule of the microelement was on the contrary. The order of the microelement of the shrub layer were Fe>Mn>Cu>Zn>Ni>Pb>Cd in LFPF and PLMF, and Fe>Mn>Zn>Pb>Cu> Ni>Cd in the other three patterns vegetation restoration.7. The order of macroelement and microelement of the litter layer was N>Ca>K>Mg>P and Fe>Mn>Pb>Zn>Cu>Ni>Cd, respectively. The distribution rule of the nutrient was the half-decomposition has higher nutrient content than the no-decomposition.8. The soil was weak acidity in PEPF and PLMF, but the pH were all more than 7.0 in the other 3 patterns of vegetation restoration stand. The soil moisture content were all very low, actually has little difference between them, the least were in the uphill in LFPF with 18.11% in soil moisture content. The order of soil bulk density from high to low was:POPF, LFMF, PLMF, PEPF, LPMF, but the order of soil porosities was on the contrary. There were significant difference among the 5 patterns of vegetation restoration stand in total P, K, Ca, Mg, Fe, and Zn, Cd and available N and K; and the most significant difference were taken place between the soil organic matter and soil total Ca. But there were no significant difference among the 5 patterns of vegetation restoration stand in total N, Cu and Mn, which had only related to the soil background value.
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