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Water circulation and nutrient cycling of forest ecosystems interact closely related. The water cycle is a medium of nutrient cycling and transport power, the coordinated water - nutrient cycling is very important to maintain the stability and function of the ecosystem. Forest vegetation on forest hydrology are mainly reflected in two aspects, water, and water chemistry. Pleioblastus (Pleioblastus amarus) is one of the main bamboo species of West rain screen Returning Farmland to Forest, has important ecological, economic and social benefits in the middle and upper reaches of the Yangtze River ecological barrier construction and regional economic development. By positioning the observations in this study, of West rain screen the bitter bamboo forest ecosystem forest outside precipitation, throughfall, stemflow, litter penetration of water, surface runoff, and 0 to 40cm soil penetration of water, 0 to 100cm soil infiltration water The chemical properties of water and water analysis (DC, DOC, DN, NH4-N, NO3 - N, SO42-, K, Ca2, Mg2), designed to reveal the redistribution of precipitation and hydrology of the West rain screen area the bitter bamboo forest ecosystem water chemical characteristics of the process to provide the basic data for the study of forests in conserving water and purify water. The study results show that: the Huaxi rainy area of ??the bitter bamboo forest ecosystem precipitation distribution (1) forest outside meteoric annual precipitation 1986.0mm, after canopy after penetrating precipitation 1877.0mm, stemflow 223.9mm. (2) total precipitation Rinnai 2100.9mm, to penetrate the water flows to the surface after litter after sorption annual infiltration volume 1060.3mm the litter holding 1040.6mm, sorption rate of 49.5%. (3) Annual surface runoff 14.2mm, the runoff coefficient of 1.3%; 40cm soil penetration of water, 161.2mm, 100cm soil infiltration of water 44.5mm. Huaxi rainy area of ??the bitter bamboo forest ecosystem hydrological process the hydrochemical characteristics (1) outside the forest precipitation and precipitation Rinnai water chemical characteristics of pH: outside the forest precipitation, and the penetration of water and stemflow pH value of the monthly variation showed spring and higher in autumn, winter and summer; outside the forest precipitation annual average pH value of 5.86, penetrating water annual average pH of 6.58, higher than outside the forest precipitation; stem fleeting average pH of 5.13, compared with the low outside the forest precipitation appears acidification. DC, DOC, DN, NH4-N, NO3 - N, SO42-, K, Ca2 and Mg2: in concentration, the forest outside the precipitation, and the penetration of water and stemflow monthly variation of the nutrients, and low concentrations in summer in winter at high concentrations; except NO3 - N, penetrate the precipitation of the nutrients in the water are greater than outside the forest; the outside Ca2 stemflow nutrient elements are greater than outside the forest precipitation. Total, except NH4-N, Forest Rainfall (penetrating water stemflow) leaching of nutrient elements are positive. (2) litter penetration water pH of the water chemistry characteristics: Litter penetration of water annual average pH value of 6.17, greater than stem flow is less than the penetration of water, its monthly variation in spring and autumn higher in winter and summer. DC, DOC, DN, NH4-N, NO3 - N, SO42, K, Ca2, Mg2: Litter in concentration, penetration of the water, the nutrients monthly variation low concentrations in summer and winter high concentrations, but the DC DOC and NO3 - N in May-June, a peak; except NH 4-N, litter penetrate the nutrients in the water are greater than the Forest Rainfall. Total positive leaching DC, DOC, NO3 - N, DN, NH4-N, of SO42-, K, Ca2, Mg2 negative leaching. Water chemistry characteristics (3) surface runoff, 40cm of soil water infiltration of water and 100cm soil penetration pH: surface runoff annual average pH of 7.51, significantly greater than the penetration of water and soil litter penetration of water, and no obvious rose variation ; 40cm soil penetration penetration of water and 100cm soil water annual average pH values ??were 6.06 and 5.77, both the trend and litter consistent penetration of water, spring and fall high winter and low in summer. DC, DOC, DN, NH4-N, NO3 - N, SO42-, K, Ca2, Mg2: in concentration, surface runoff, 40cm soil penetration penetration of water and 100cm soil water nutrient elements Monthly changes in law consistent summer concentration low winter high concentrations, but the of surface runoff DC and DOC concentration has a peak in May-June 40cm soil penetration penetration of water and 100cm soil water DC DOC, DN, NH4-N and NO3 - N concentration in 5 to June there is a peak; surface runoff DN, NH4-N, SO42-, and K concentrations less than litter penetration of water, the remaining nutrient elements is greater than the the litter penetration water: In addition to SO42-and Ca2, 40cm of soil The osmotic water nutrient elements are less than the penetration of water and 100cm soil litter osmotic water; total nutrient elements in the 0-40cm and 0 ~ 100cm soil layer adsorption effect.
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