Research On Biomass And Soil Nutrient Content Of Cupressus Torulosa Plantation

Cupressus torulosa,also known as the Himalayan Cypress,is an evergreen coniferous tree of the genus Cupressus,belonging to Up-ressaceae.Cupressus torulosa native to southeast Tibet,Mottle,Linzhi and other regions,northern India,Bhutan,Nepal,Sikkim and other countries are also distributed.The tree species is light-loving and can grow on neutral,slightly acidic and calcareous soil,and the fastest on the rich calcium soil.Cupressus torulosa has strong adaptability,poor tolerance,drought resistance,straight and straight trunk,beautiful tree shape characteristics and so on.Therefore,it is an excellent timber,greening tree.Cupressus torulosa was introduced into Zhaohua area of Guangyuan City,Sichuan Province in 1988,but its ecological and biological characteristics were not systematically studied.Therefore,the growth characteristics of 27 year old Cupressus torulosa plantation in Zhaohua District,Shaba Township and Yuanba Town of Guangyuan City were studied in this paper.Biomass and soil nutrient content in forest land were studied.and compared with the local tree species of Sichuan Province similar to the site conditions,in order to further understand the characteristics of Cypress species and the future development of cedar plantation.It provides theoretical basis and technical support for improving carbon sink function and strengthening management and management.It is important for improving local ecological environment,mitigating global climate change,increasing human timber forest and so on.Want meaning.The results showed that it was a very successful case to introduce Cupressus torulosa into Sichuan.When the tree age and site conditions were the same,the biomass,productivity and carbon sequestration ability of the Cupressus torulosa were better than that of the Sichuan Cypress.The main conclusions were as follows:?1?Growth characteristics:The height,DBH and volume of the standard cypress tree were 14.65m,20.31cm and 0.20583m³respectively.In the early stage of height growth of cypress,the growth was slow,the number of tree height was about 22 years,the diameter of DBH fluctuated with the age of tree,and the number of DBH was the mature period of DBH,and the potential of volume growth was large,and the mature age of volume was less than 27 years.?2?Water content characteristics:the average moisture content of different parts of Cypress sinensis is different,the order of water content of each organ is:cone>trunk>leaf>branch,the moisture content of root decreases with the decrease of root diameter,the order of water content of each organ is:cone>trunk>leaf>branch.The order of root moisture content was:root pile>thick root>middle root>fine root.?3?Biomass per plant:the biomass of standard wood was 88.00kg and the maximum biomass of cypress was 302.22kg,which was 3.43 times of that of standard wood.The distribution law of aboveground organ biomass was as follows:trunk>branch>leaf>cone.The distribution law of branch biomass was:first branch>second branch>small branch,and the distribution law of underground biomass of single tree was root pile>thick root>medium root>fine root.?4?The biomass of the stand:the total biomass of the 27a and cypress plantations is 179.61t·hm^-2,which is higher than the 126.46t·hm^-2 of 30a in the middle area of Sichuan and the 1.42 times of the cypress cypress.The distribution rules of the biomass of the trees are:the tree layer>litter>herbaceous layer>shrub layer.The biomass of Arbor layer is 156.19t·hm^-2,which is higher than that of Cypress arboreal layer(124.02t·hm^-2),which is 1.26 times of that of Cypress chinensis,0.42t·hm^-2 in shrub layer,0.75t·hm^-2 in herbaceous layer and 22.25t·hm^-2 in litter layer.The rules of biomass distribution of each organ stand were as follows:trunk>branch>root>leaf>cone.?5?The total productivity of stand productivity and carbon storage of 1:27a plantation was 6.65t·hm^-2·a^-1.The productivity of Arbor layer was 5.78t·hm^-2·a^-1,which was higher than that of 30 years old cypress tree layer in central Sichuan,and the productivity of shrub layer was 0.02t·hm^-2·a^-1,that of herbaceous layer was0.03t·hm^-2·a^-1,and that of litter layer was 0.82t·hm^-2·a^-1.The total carbon reserves of 27a in Berlin are 93.40t·hm^-2.tree layer carbon reserves of 81.22t·hm^-2.The carbon reserves of shrub layer are 0.22t·hm^-2,and the carbon reserves of the herb layer are 0.39t·hm^-2.?6?Soil nutrient content:the range of soil pH was 6.22⁷.56,which was slightly acidic or neutral,the distribution range of organic carbon was 7.9g·kg^-121.6g·kg^-1,the range of total nitrogen content was 0.043g·kg¹.200g·kg.The distribution range of available nitrogen content was 0.07g·kg^-11.97g·kg^-1 and the total phosphorus content was 0.045g·kg^-10.139g·kg^-1.From layer A to layer C,soil organic carbon content increased gradually,soil total nitrogen content and available nitrogen content decreased.The total phosphorus content of the soil decreased first and then increased.The soil in layer A played an important role in plant growth.The organic carbon content in layer A was lower than that in layer A,and the content of available nitrogen and total phosphorus was the largest in layer A,which was higher than that in layer B C.