Study On Seasonal Dynamics Of Litter And Correlation Between Litter Nutrient And Soil Properties Of Pinus Yunnanensis Var.

Litter is the carrier of forest plant and soil nutrient cycling and material exchange,which is closely related to soil physical and chemical properties,soil fertility,soil microbial activities and so on,therefore,forest litter is one of the most important subjects in forest ecology,forest soil science and Biogeochemistry.From Pinus yunnanensis var.is a pioneer species in Southwest China,but previous studies to investigate Pinus yunnanensis var.mainly concentrated in the geographical distribution,growth pattern,genetic diversity,population spatial distribution pattern.Study on the litter of Pinus yunnanensis var.is still blank.In this paper,through to investigate natural Pinus yunnanensis var.mixed forest litterfall and nutrient dynamics were studied,revealing the relationship between litter biomass,composition and seasonal dynamics of litterfall and nutrient and soil nutrients,and provide scientific basis for the structure and function of deep understanding.Pinus yunnanensis var.natural mixed forest ecosystem.Research indicates:1.The litter of Pinus yunnanensis var.is 12462.90～14273.49kg/hm2 every year..The main content of the litter is coniferous,in a number 4047.17～7353.23kg/hm2,accounting for more than 30%of the total litter,The broadleaf of litter is 2205.56～3815.84kg/hm2,which accounted for more than 15%of the total litter,the leaf of litter accounted for more than 60%of the total litter.2.The litter fall amount of the half-tropholytic and the untropholytic is similar.The boimass shows that the half-tropholytic is larger than the untropholytic.The samples of boimass are water content respectively:the untropholytic 62.67%、34.68%、63.15%,and the half-tropholytic 63.54%、52.07%、66.57%,besides.3.The litter throughout the year appears an obvious trend of two-peak curve in Pinus yunnanensis var..The value of peak is respectively April and November.The least amount of litter appears in September.The trend of coniferous litter is many-peak,and the peak value is April,August,November.The change pattern of the broadleaf and debris are two-peak.The value of peak in the broadleaf is on April,November or January.The value of peak in the debris is on April,or from October to November.The change pattern of the branches has no common rule.4.Pinus yunnanensis var.is rich in crude ash,and the order of its component is:broadleaf>coniferous>debris>branches,and its accumulation is half-tropholytic>untropholytic.The crude ash of its component respectively the coniferous:3.49%、3.52%、6.77%;broadleaf:4.32%、5.25%.8.21%;branches:2.98%、4.16%、5.80%;debris:1.99%、4.17%、3.98%;untropholytic:10.52%、10.07%、13.76%;half-tropholytic:49.17%、35.19%、36.48.5.Measured and compared the nutrient concentration of the litter of Pinus yunnanensis var.,the results of the three samples are consistent.Its size order is N>K>Ca>P>Fe>Mg>Cu.The concentration of each component is different,and the range of every nutrient is:N 4.72～15.01g/kg,P 0.40～0.69g/kg,Ca 0.35～4.82g/kg,Fe 81.23～281.44mg/kg,Mg 20.31～94.00mg/kg,Cu 6.91～37.05mg/kg,K 0.98～5.56g/kg.6.The 3 kind of litter components Fe,Cu,Ca unified annual return is the return of the amount of performance for the rule of Fe No.1 plots>2 plots>3 plots;Cu return size shows No.3 plots>2 plots>1 plots;Ca return amount for the performance of the 3 sample>1 sample>2 sample.Other elements each annual return of no regularity of unity.7.The amount of litter and the return of each element of each component were correlated with soil nutrients,the results shows that soil organic matter with the branches of N,P,Cu and K,Fe of the coniferous and Cu of broadleaf and Cu of debris;soil nitrogen with N of branches,Mg,Fe,K of coniferous,Cu of broadleaf,Cu of debris;soil total phosphorus and K.Mg of coniferous and K of branches;soil total potassium and needles of N,Mg;soil available potassium and N,K of coniferous and branches,showing a significant correlation.