| Soil respiration is an important part for the Global carbon cycle, not the single factor but multiple factors affect the variations of soil respiration rate variations. It is the less part of the current study. What is the relationship between the stability of soil respiration spatial pattern and relative stability of stand structure. This is very difficult and important for accurately finding out the percentage of soil respiration componment. The Pinus massoniana forest is the second big forest ecosystems in our country, so it has very important implications to research on the soil respiration rate of the Pinus massoniana forest, and that is influence on soil organic carbon pool of forest ecosystems. It is relationships between biological factor and soil respiration spatial pattern.The results was that:(1)Fine-root biomass of measure point depends on the of the trees and the distance with the trees, makes use of fine-root biomass and the sum.that of the sum of DBH size to do with the ratio of the distance for regression analysis, the triple simulation equation were that:March:y=0.1073x10067,R2=0.7667; July:y=4.2964x05478. R2=0.7641:October: y=3E-06x2.64.R2=0.7404. Fine-root biomass and the DBH size to do with the ratio of the distance were Significantly related.(2)Soil respiration and its components displayed seasonal dynamics obviously.with maximum values in summer and minimum values in winter. The maximum soil respiration rate was2.95μmol.m-2.s-1in August; the minimum soil respiration rate was0.82μmol.m-2.s-1in December. Soil autotrophic respiration accounted for20.4%-28.3%,Soil heterotrophic respiratory rate accounted for72.7%-79.6%.(3) Fine-root biomass was different in different seasons, it manifests summer> spring> autumn> winter. Fine-root biomass mainly in twenty centimeters of surface soil, with maximum ratio was71.17%in spring. And the ratio of the two millimetre. Fine-root biomass was more than50%. (4) Forest litter displayed seasonal dynamics obviously, the biggest output presented in December. Pine needle was the largest share of forest litter, which the percentage was45.9%. branch and sundries percentage were21.5%and29.4%, the lest part was bark, which percentage was3.1%.(5) Equation for simulation herb layer and soil breathing was:y=2.00x+2.06(R2=0.169, P<0.05) Compare with the coverage of shrub layer, the herb layer coverage could better performance the relationship between biomass of the point of fine roots and oil biomass size breathing size.(6) Relationships between month after month litter accumulated and soil respiration accumulated from month after month amount were positive correlation. The production in different month would affect the soil heterotrophic respiratory in the next mouth, and they have significant. The size of soil heterotrophic respiratory to a large extent depends on the sun of sundry and pine needles, they have significant positive correlation between the linear relationships.(7) Stand structure parameters of the DBH size and fine roots biomass were significant power function. The simulation equation were July:y=0.0263x0.6122、 R2=0.369、P=0.026; September:y=7E-05x1.5114, R2=0.3566、 P=0.044; October: y=0.0002x1.3596、R2=0.3109, P=0.043; December:y=0.0047x0.7734, R2=0.2411、 P=0.032。Relationships between soil root respiratory rate and the stand structure parameters of the sum of DBH size to do with the ratio of the distance were high-end significant correlation. |
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