| Litter is a major index in the study of biomass yield, nutrient recycling and energy flow in forestry ecosystem. It has significance to the organic formation and nutrient release because of the follow reasons: major content of the forest productivity; major material pool of forest organic; major course of the material cycling and energy flow in forest ecosystem. Leaves amounts 60%-80% of the litter. Their decomposition is a key factor in the ecosystem functions and the decomposition process reveals the fundamental characteristics of nutrients recycle. In order to remain the sustainable productivity of the forest, it is very important for the nutrient to return to soil through litter, especially the comprehensive fertilization is impossible in our country.The author investigated the structure of 8 representative community in the Luoboyan Natural Reservation in Fujian Province, analyzing characteristics of vegetation and structure of Phoebe bournei community in subtropical natural forest. The result shows that the structure separates obviously into three layers: tree, shrub and herb. There are many species in the vegetation with 55 in the tree layer, 82 in shrub layer, 22 in herb layer. They are all growing healthily. In the tree layer, the dominance species are Phoebe bournei, Cyclobalanopsis glauca, Loropetarum chinense, which accounts for 5.5% of the total species numbers, while the IV (important value) 37.22% of all. In the shrub layer, 6.1% species occupies 24.33%.The young Phoebe bournei is in the second place, which reveals the community is in stable condition because the regeneration is normal. There are more Pteridophyta species in the herb layer and many inter-community species because of the high coverage, more rainfall and high moistening. The community is favorable of the environmental with quick growth, dark-green aspect and stable forest form. Their average crown density is 0.8.The author analyzed the storage amount of the un-decomposing and sub-decomposing layers by investigating the remnant litter under the forest. The result shows that the un-decomposing remnant of Phoebe bournei litter accounts for 32.04% of the total remnant and other species 25.97%; the sub-decomposing has the dominance of 41.99%. The reason may be the sample spots are in good conditions .So the structure is stable and the decomposition rate is high. To some extend, it reflects the facts that the litter has the ecological function of containing rainfall and balancing the water in ecosystem because the total water-holding amount and the average water-holding rate are so high that they reached 2.31874t/hm2 and 61.09% respectively. Moreover, the water holding in the un-decomposition is less and that is relatively more in thesub-decomposition, which reveals the sub-decomposition contributes more to the ability of holding and storing water.By studying apprehensively the process of litter decomposition and comparing quantitatively the other subtropical plantation species, the author quantitatived the mass changes and build the dynamic model to analyze the characteristics and to predict the half-life. The outcome shows that in prophase Phoebe bournei, Cinnamomum camphora, Podocarpus nagi and Taxodium ascendens have lost most of the dry mass, the remnant amount occupied 35.45%-66.95%. During Sep. to Nov. 2002,the rate began to decrease while increased after November. Comparing with the Cinnamomum camphora, Podocarpus nagi and Taxodium ascendens, the decomposition of Phoebe bournei is the slowest and the remnant amount is 52.33% of the original amount after one year. It took 1.027 year and 4.44 year respectively for the litter of Phoebe bournei the longest time to decompose to the extent of 50% and 95%. The rate order of the 4 species decomposition is Cinnamomum camphora > Podocarpus nagi> Taxodium ascendens>Phoebe bournei.Studying on the rules of concentration, releasing amount and releasing rate of 6 major nutrient elements and 5 macronutrient elements in the decomposing process of Phoebe bournei litter and comparin...
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