Biomass&Nutrient Accumulation And Distribution Of Chenshan Red-heart Chinese-fir

Chinese fir is an unique fast-growing timber species in southern China,and it plays a decisive role in plantation production practice;Red-heart Chinese fir is one of the variation types of Chinese fir with high red heart rate and fine materials,which can be used as the first-class decoration and construction materials.It is not only of important economic value,but also of great ecological value.Thus,the development,utilization and protection of this species are getting more and more attention.This study took the 26-year-old Red-heart Chinese fir plantation in Chenshan forest farm of Anfu county,Jiangxi province as the research object.The biomass,nutrient accumulation and distribution of Red-heart Chinese fir were studied by using methods of field standard sample plot investigation and indoor chemical nutrient analysis,so as to compare the nutrient distribution differences between heartwood and sapwood.The main research results were as follows:(1)Biomass:The biomass distribution in each layer of Red-heart Chinese fir plantation was:Tree layer>Fir litter layer>Other litter layer>Shrub layer>Herb layer.Biomass distribution in each organ of tree layer was:sapwood>heartwood>root>bark>branch>leaf.The biomass of different diameter classes in Red-heart Chinese fir plantation was normally distributed.The biomass of 16-18 cm diameter classes reached the maximum,accounting for 19.6%of the biomass of the whole tree layer.The biomass of shrub and herb layer were 2.54 t/hm~2,and 1.89 t/hm~2 respectively.The total biomass of 26-year-old red-heart Chinese fir was 171.58 t/hm~2.(2)Major-elements contents:?the major-elements average contents in tree layer was:C>N>Ca>K>Mg>P.But in the bark and leaf were:C>N>Ca>K>P>Mg;The contents of C in different organs of Red-heart Chinese Fir were:trunk>root>leaf>branch>bark,the contents of N?Mg and P in which were:leaf>branch>bark>root>trunk,and the contents of K and Ca behaved as:leaf>bark>branch>root>trunk.Except for C,the contents of other major-elements in sapwood were higher than in heartwood;The contents of major-elements in root decreased with the increase of root diameter.?The major-elements contents in shrub layer were:C>N>Ca>K>Mg>P,except for Ca,the other major-elements contents were higher in the aboveground part than that in the underground part;The major-elements contents in herb layer were ordered as:C>N>K>Ca>Mg>P,and all the major-elements contents were higher in the aboveground part than that in the in underground part.?The major-elements average contents of Red-heart Chinese fir litter were:C>N>Ca>Mg>K>P;The major-elements average contents of other litter were:C>N>Ca>Mg>K>P;? The major-elements contents in soil were:C>K>Mg>N>Ca>P.(3)Minor-elements contents:The minor-elements average contents in tree layer were:Mn>Fe>Ba>Zn>Sr>Sn>Cu>Li>As>Ti;The contents of minor-elements in root decreased with the increase of root diameter;Sn?As?Cu and Ti contents in heartwood were higher than in sapwood,but Sr?Ba?Fe?Li?Mn and Zn contents in sapwood were higher than in heartwood.?The minor-elements contents in shrub layer were:Mn>Fe>Ba>Zn>Sr>Ti>Cu>Li>As>Sn;Sn?Ba?Cu?Li?Mn and Zn contents were:aboveground part>underground part,Sr?As?Fe and Ti contents were:underground part>aboveground part;The minor-elements contents in shrub layer were:Fe>Mn>Ba>Zn>Sr>Ti>Cu>Li>As>Sn,Sr?As?Mn and Zn contents were:aboveground part>underground part;Sn?Ba?Cu?Fe?Li and Ti contents were:underground part>aboveground part.?Red-heart Chinese fir litter average contents were:Fe>Mn>Ba>Zn>Sr>Ti>Cu>As>Sn>Li;Other litter average contents were:Fe>Mn>Ba>Zn>Sr>Ti>Cu>Li>As>Sn;? The minor-elements contents in soil were:Fe>Mn>Zn>Ba>Li>Cu>Sr>Sn>Ti>As.(4)The major-elements accumulation and distribution:? The major-elements accumulation in the whole stands were 105445.33 kg/hm~2.The distribution pattern of major-elements at different layer in whole stand were:tree layer>fir litter>shrub layer>other litter>herb layer;?The major-elements accumulation in tree layer were 98884.21kg/hm~2,and the order of major-elements accumulation were:C>N>Ca>K>Mg>P;The major-elements accumulation of different organs were:sapwood>heartwood>root>bark>leaf>branch.? The major-elements accumulation in shrub layer were 1435.12 kg/hm~2;The major-elements accumulation in herb layer were 954.45 kg/hm~2.? The major-elements accumulation of Red-heart Chinese fir litter were 2990.35 kg/hm~2;the major-elements accumulation of other litter were 1181.19 kg/hm~2.(5)The minor-elements accumulation and distribution:?The minor-elements accumulation in the whole stands were 57.90 kg/hm~2.The distribution pattern of minor-elements at different layer in whole stand were:tree layer>fir litter>other litter>shrub layer>herb layer;?The minor-elements accumulation in tree layer were 33.06 kg/hm~2,and the order of minor-elements accumulation were:Mn>Fe>Ba>Zn>Sr>Sn>Cu>Li>As>Ti;The minor-elements accumulation of different organs were:leaf>bark>sapwood>branch>root>heartwood.?The total minor-elements accumulation in shrub layer were 2.67 kg/hm~2.The minor-elements accumulation in herb layer were 2.29 kg/hm~2.?The minor-element accumulation of Red-heart Chinese fir litter were 13.48 kg/hm~2;the minor-elements accumulation of other litter were 6.39 kg/hm~2.The results provide basic data for the study of the material cycle of Red-heart Chinese fir plantation ecosystem and the theoretical support for forest cultivation and sustainable management of Red-heart Chinese fir plantation.In addition,our results also provides theoretical guidance for the development and utilization of Red-heart Chinese fir plantation and give full play to its ecological and economic benefits.