| Dendrocalamus oldhamli, Dendrocalamopsis vario-striata, Dendrocalamopsis beecheyanus var.pubescens, Dendrocalamus latiflorus and Dendrocalamus brandisii are plants of wide usage, short growing cycle and wide accommodation. The kind of tree in the coastal shelterbelt is singleness. The forest quality has declined, and exists that the second era renovates is difficulty. And the ability of selt-reproduced of the bamboo is strong. That the rhizomatous is mutual tortility is perfect vegetation, the climate of southeast coastal is adaptable to the growth of bamboos. There are not only economy benefits but also ecolgy benefits of D.oldhamli and D.vario-striat et al. The present study was the first systematic exploration on the ecosystem characteristics of bamboo forests. These include structure of biomass, hydrology dynamic, nutritent characteristics and circulation. The main findings were as follows.(1) The growth condition and adaptability of bamboo are good in Coastal sandy area, but it has a bit of contrast on account of difference in adaptability. The reserve rate of D.vario-striat was 100%, but D.brandisii's only was 90.1%; the height and diameter of D.brandisii were 6.38 m and 4.32 cm respectively, D.oldhamli's were 4.51 m and 3.00 cm respectively.(2) The water rate of bamboo in coast is preferable, which meet the needs of bamboo's physiological activities. The bamboo in coast is adapted well to drough climes. Concerning average water rate of components over ground, leaf of one-year-old bamboo was lowest and branch of two-year-old bamboo was highest except D.vario-striat. The sequence of average water rate of components under ground was stem underground>root. the crop of one-year-old D.latiflorus and D.brandisii was high in average water rate, which reached to 73.72% and 73.37% respectively. D.beecheyanus var.pubescens ranked last, which was 65.34%. The average water rate of two-year-old D.vario-striat crop was highest, to 45.29%.(3) with the increasing of height, the biomass in one-year-old individual bamboo decreased, although increased and then desreased in two-year-old individual bamboo. In the distribution of organ biomass, the sequence was crop>branch>leaf over ground and stem>root under ground. In the distribution of biomass in bamboo forest, the arbor's biomass was the main part, which accounted for over 70%. The herbage ranked second, it was litter lastly. The total biomass of D.vario-striat forest was most, which reached to 33.991 hm-2.(4) The bamboo forests can adjust rainfall's distribution. Rainfall was the dominant factor which affected interception, throughfall and stem flow. In a certain rainfall class, with the increasing of rainfall, the interception, throughfall and stem flow increased. The annual amount of interception and stem flow were 179.3 mm and 32.9 mm respectively in D.beecheyanus var.pubescens. the annual amount of throughfall was most, which reached to 853.7 mm in D.oldhamli.(5) Variation of soil moisture affected mostly by rainfall. Soil moisture had two peaks in ayear due to rainfall. The vertical distribution law of soil moisture increased with increasing in soil depth (below 20 cm deep).(6) The water holding capacity of arbor and litter were most in D.vario-striat forest, which amounted to 16.86 t hm-2 and 10.58 t hm-2 respectively. The water holding capacity of herbage was most in D.oldhaml forest, which reached to 8.93 t hm-2. The soil (0-40cm deep) storage capacity was the main part of total water holding capacity, which accounted for over 95%.(7) N Concentration of all organs was topmost in N, P, K, Ca and Mg concentration and Mg concentration was higher than Ca concentration. N, P, K, Ca and Mg concentration in one-year-old bamboo were all higher than that in two-year-old bamboo.(8) The vertical distribution law of nutrient amount was not the same as that of biomass. With the increasing of height, the nutrient amount decreased in individual bamboo crop, increased and then decreased in individual bamboo branch and leaf. N amount of leaf was most in e...
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