Research on Leaf Litter Decomposition and Hydrological Characteristics of Dominant Tree Species in the Caohai Wetland Watershed
Using the method of leaf litter decomposition bag to study the litter decomposition's residual rate,decomposition rate,regression model and hydrographic trait by decomposition process.The dominant tree species(e.g.,Cyclobalanopsis glauca,Quercus f abri,Alnus cremastogyne,Populus yunnanensis,Pinus yunnanensis and Cunninghamia lanceolata) in Caohai wetland watershed forest was selected as the research object.The result showed that:(1)The leaf litter accumulation decomposition rate was (24.0 ± 1.4)% (Cyclobalanopsis glauca),(24.1±2.0)% (Quercus fabri),(26.6±2.6)% (Alnus cremastogyne),(26.0 ±0.7) % (Populus yunnanensis),(13.8±2.6) % (Pinus yunnanensi) and (13.8±0.9) % (Cunninghamia lanceolata),respectively by the decomposition 12 months later,the litter decomposition rate of leaf accumulated had extremely significant difference (F =10.28,P < 0.01).(2) The leaf litter decomposition equation conformed to the Olson Exponential decay model (Lr =ae-kt).The leaf litter decomposition constants of broadleaved plant and conifer plant were 0.019~0.024 and 0.011 ~0.012,respectively.The leaf litter decomposition rate was influenced by leaf form,the leaf litter decomposition rate of broadleaved plant was significantly higher than that of conifer leaf plant.T0.5 and T0.95 in broadleaved plant was 2.27~3.06 years and 10.46~13.16 years,that in conifer plant was 4.61~5.20 years and 20.60~20.64 years.(3)The leaf litter water-holding rate (Rl) and decomposition residual rate(Lr) showed a significant linear relationship(Rl =aLr+b,P<0.05).(4)The soil moisture(Rs) and leaf litter water-holding rate(Rl) showed a significant inverse function correlation(Rs =a/Rl + b,P<0.05).
wetland watersheddominant tree speciesleaf litter decompositionhydrological characteristics