杉木人工林养分循环随林龄变化的特征  

Changes in nutrient cycling with age in a Cunninghamia lanceolata plantation forest

作　　者：陈日升 康文星[1,2,3] 周玉泉 田大伦 项文化[1,3] CHEN Ri-Sheng1,KANG Wen-Xing1,2,3,ZHOU Yu-Quan1,TIAN Da-Lun1,2,3,XIANG Wen-Hua1,3(1.Central South University of Forestry and Technology, Changsha 410004, China;2.National Engineering Laboratory for Applied Technology of Forestry ＆ Ecology in South China, Changsha 410004, China;3.Huitong National Field Station for Scientific Observation and Research of Chinese Fir Plantation Ecosystem in Hunan Province, Huitong, Hunan 418307, Chin)

机构地区：[1]中南林业科技大学,长沙410004 [2]南方林业生态应用技术国家工程实验室,长沙410004 [3]湖南会同杉木林国家重点野外科学观测研究站,湖南会同418307

出　　处：《植物生态学报》2018年第2期173-184,共12页Chinese Journal of Plant Ecology

基　　金：国家林业公益性行业科研专项(201104009);科技部公益性研究项目(2007-04-15);国家野外科学观测研究站项目(20080615)~~

摘　　要：为弄清杉木(Cunninghamia lanceolata)人工林不同林龄的养分循环特征,为人工林丰产的经营管理提供科学依据,利用湖南会同杉木林25年的定位连续测定数据,根据杉木生长规律和养分吸收动态对杉木林不同林龄的养分循环进行了研究。结果表明:对于同一林龄的杉木,器官养分浓度大小依次为叶>枝>皮>根>干。林龄小于12年的,杉木养分浓度随林龄增加而增高;林龄大于12年的,杉木养分浓度随林龄增加而降低。养分年均吸收量随林龄增长的变化曲线为双波峰。养分归还量随着林龄的增加逐渐增加。同一林龄,各营养元素的利用效率都是磷(P)>钾(K)>氮(N)>镁(Mg)>钙(Ca)。林分郁闭后,各营养元素的利用效率随着林木生长而增大。同一林龄,Ca、Mg的循环强度大于N、P,各营养元素循环强度随林龄增长的变化曲线都为抛物线。同一林龄,N、P、K被杉木利用的时间比Ca、Mg长,各元素被杉木利用的时间随着杉木生长的进行而缩短。研究显示:不同林龄的养分吸收量除受生产量控制外,还受这个林龄和前一个林龄杉木体内养分浓度的差异制约;杉木体内养分再分配及贮备机制、杉木生长规律和不同生育阶段对养分的利用效率等共同调节控制着养分循环过程。Aims The purpose of this study is to investigate the characteristics of nutrient cycling in Cunninghamia lanceolata plantations） with different ages, and to provide scientific basis for the management of high-yield plantations in China. Methods In this study, we used the ecological data of the past 25 years in Hunan Huitong Ecological Station and analyzed the nutrient cycling characteristics of the C.lanceolata plantation forests with different ages according to the law of tree growth and the dynamics of nutrient uptake. Important findings For most nutrients, their concentrations ranked in order as leaf 〉 twig 〉 bark 〉 root 〉 stem for all C. lanceolata trees with any ages. When the tree age was less than 12 years, nutrient concentrations increased with age, while they decreased with age when the tree was more than 12 years old. The changes in average annual nutrient uptake with age showed two peaks. Nutrient return gradually increases with age. For the same age, the nutrient use efficiency followed the order of phosphorus （P） 〉 potassium （K） 〉 nitrogen （N） 〉 magnesium （Mg） 〉 calcium （Ca）. After the stand was closed, the nutrient utilization efficiency increases with the growth and development of trees. The cycling intensity of Ca and Mg was greater than that of N and P at the same stand age. The changes in nutrient cycling intensity with age varying curve with stand age acted as parabolic curve. Utilization of N, P and K was longer than displayed a parabolic shape for all elements. The utilization time of each element got shorter with increasing stand age. These results suggested that the nutrient uptake in different growthstages was not only controlled by the quantity of biomass, but also affected by the difference in nutrient concentration between previous and current stages. The nutrient cycling processes were jointly controlled by the mechanisms of nutrient redistribution and storage in Cunninghamia lanceolata,during the growth and development stages, and the nutrie

关 键 词：杉木 人工林 不同林龄 养分循环 湖南 会同 

分 类 号：S791.27[农业科学—林木遗传育种]