| Dendrocalamus latiflorus, is a kind of plant of wide usage, short growing cycle and wide accommodation. It also has high economic benefit, as well as social benefit and ecological benefit. As the biological and ecological properties of it have not been fully recognized, our knowledge to cultivating moutain Dendrocalamus latiflorus was still in perceptual stage. Furthermore, restricted by market fluctuation, it was difficult to develop the cultivating of it to a level of high efficiency, high yield, high quality and stability, let alone to put its' ecological effect, social effect and sustainable management in to reality. As the major managing measure for scattered and mixed bamboo forest, till now, plough still has not been applied in clump bamboo forest. Experiment plots were established in Xiaosharigcheng working unit of Nanjing National Forest Farm, applying 3 types of soil plough measures separately, including overall plough, strip plough and ditch plough surrounding stem underground(in each March), to compare the economic benefit, soil and water losses of each measure. The investigating content involved the shoots yield and annual profit, overland flow, , the losses of sediment and nutrient. Meanwhile, other links of hydrology characteristic and nutrient dynamic were also studied, the former contained first distribution of rainfall in crown and forest water-storage capacity, the latter contained the law of litter's producing, decomposing and nutrient return, eluvial return of nutrient. The main conclusions were as follows:(1) In the 3 treatments, the shoots yield and economic benefit of the strip ploughed treatment were the best, and it also had the highest output and profit, which amounted to 25520kg玥m~2 and 17778 yuan-hm-2.(2) Plough improved the physical and chemical property of soil. The property of soil in overall ploughed treatment was the best among the 3 treatments, its permeability, poprosity and water-holding capacity were the most excellent, of which the final infiltration speed was 9.62mnTmin-', the total poprosity in 0-20cm and 20-40cm deep were 56.24% and 47.69% respectively, and the water storage capacity in 0-40cm deep was 1503.29 t'hrn-2.(3) In water and soil losses, annual overland flow and sediment losses was the highest in overall ploughed treatment, which reached to 30.37mm and 234.45kg-hm-2 repectively. The strip ploughed treatment ranked second, then it was the ditch ploughed treatment. Difference between strip ploughed treatment and ditch ploughed treatment was not obvious. The correlation between over-land flow and rainfall could be modeled by index function fairly. Overland flow and sediment losses varied in season, which was much more in rainy seasonthan that in drought season.(4) The sequence of annual N, P and K losses of overland flow was overall ploughed>strip ploughed>ditch ploughed treatment. The difference of annual losses of N, P was not obvious among the 3 treatments. The difference of annual losses of K was extremely obvious among the 3 treatments, but not obvious between strip plough and ditch plough. Affected by fertilization and overland flow amount, the nutrient amount in overland flow in Jun. and Aug.,2000 were obviously high than that in other month.(5) Annual N, P and K amount had surplus in the ecosystem of 3 treatments. The soil was loosed and the roots spread better and absorbed more nutrient in strip ploughed treatment. Meanwhile, the speed and quantity of nutrient losses are relatively low. The nutrient using rate of strip ploughed treatment was the highest among the 3 treatments, and the annual surplus of N, P and K in the ecosystem was the lowest, which was 783.18, 120.68 kg* hm'2 and 184.50kga hm-2 respectively. The annual input of N, P and K through rainfall and fertility were: 951.85, 152.23 kg* hm'2 and 281.90 kg- hm-2; the annual output of N, P and K through shoots, bamboo wood and overland flow were: 168.67 ,31.55 kg* hm-2and 97.41 kg* hm-2.(6) Rainfall is the dominant factor which affect interception, throughfall and stem flow...
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