| Storage amount, composition, seasonal dynamics and decomposing dynamics of litterfall of Pinus sylvesstris var.mongolica stand and Quercus mongolica stand in Maoershan mountain was studied, using theory and method of plant ecology, microbiology and agrology. The results are as follows:1. During three years from 2003 to 2005, the amount of litterfall of Pinus sylvesstris var.mongolica stand (5524.01Kg.hm-2.a-1) was more than that of Quercus mongolica stand (3907.96Kg.hm-2.a-1)) , and there were significant difference between two year, and increased year after year. Significant difference of litterfall amount in different years between the two stands was observed also. The ratio of leaffall amount to total amount of litterfall was more than 60% in two stands.2. There was one peak of monthly dynamic of total litterfall in 2003 and 2005, and two peaks in 2004 in Pinus sylvesstris var.mongolica stand. But it showed one peak of total litterfall in Quercus mongolica stand, and the pattern of monthly dynamic of leaf and branch litterfall is also unimodal in both of the stands;the pattern of flower was unnimodal, and amount of branch, bark and fruit-fall fluctuate strongly in the pine stand in different monthes;Flower of the oak stand withers mainly from April to September, while fruit mainly from July to September.3. The space distribution pattern of the litterfall layer was L>H+F, and the storage in H+F layer was more than 50% of the total amount. In the pine stand the total amount of litter-fall layer was 7884 Kg.hm-2, and 5776 Kg.hm-2 in the oak stand.4. It showed exponential relationship between leaf-fall decomposition rate and time in both stands, which showed fast stage of decomposition before 320 days, and slow stage after that.5. The accumulation of all nutritious elements (N, P, K, Ca, Mg) in both stands increased from L layer to F+H layer (except Mg in the pine stand);In both of the mix broad leaf sample and single oak leaf sample in the oak stand, N, P, K, Ca and Mg released (except N in mix broad leaf sample) during decomposition process. In pine forest, the 5 elements released with single needle sample and mixed leaf sample decomposition, showing direct releasing pattern, and fast decomposition rate during the prophase of the decomposition. P accumulated with the leaves decomposition. C element concentration of litter sample of oak stand reduced linearly with the decomposition process, and wave-likely decreased in the pine stand.6. C/N of the different litterfall layers in both stands was L>F>H. During the decomposing of leaf, C/N reduced gradually with the decomposition of literfall in both of the mixed leaf sample and single needle sample in the pine stand and mixed broad leaf in the oak stand The decomposing rate depended on the leaf-fall characters, especially their C/N.7. The bacteria amount of the litterfall layer in both stands was L>H>F, the number of actinomycetes was H>F>L, fungi was L>F>H respectively. Bacteria and actinomycetes in both stands deduced with time going, but fungi increased in September. And the monthly total amount microorganism was more in the oak stand than that of in the pine stand.8. Catalase activity in litterfall layer was L>F>H in the pine stand, and F>H>L in the oak stand. Invertase activity in litterfall layer was F>L>H in the pine stand, and H>F>L in the oak stand;Proteinase activity in litterfall layer was L>F>H in both stands;Urease activity in litterfall layer was L>H>F in the pine stand, and F>H>L in the oak stand respectively. Catalase activity and Proteinase activity in the oak stand is more than those in the pine stand.9. Catalase activity of litterfall layer in two stands increased with decomposing of litterfall from May to September. And invertase activity reduced gradually in litterfall layer of the oak stand, and deduced at first and then increased in the pine stand, Proteinase and urease activity of litterfall layer in both stands deduced at first and then increased.
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