色季拉山急尖长苞冷杉林线过渡带土壤化学计量特征  

Soil Stoichiometric Characteristics in the Timberline Ecotone of Abies georgei var.smithii Forest in Sejila Mountain

作　　者：汪汉驹 李江荣[1,2,3] 郑维列 陈康[1,2,3] 陈文盛 丁慧慧 WANG Han-ju;LI Jiang-rong;ZHENG Wei-lie;CHEN Kang;CHEN Wen-sheng;DING Hui-hui(Research Institute of Xizang Plateau Ecology,Xizang Agriculture&Animal Husbandry University,Linzhi Xizang 860000,P.R.China;Key Laboratory of Forest Ecology in Xizang,Ministry of Education,Linzhi Xizang 860000,P.R.China;National Key Station of Field Scientific Observation&Experiment of Alpine Forest Ecology System in Linzhi,Linzhi Xizang 860000,P.R.China)

机构地区：[1]西藏农牧学院高原生态研究所,西藏林芝860000 [2]西藏高原森林生态教育部重点实验室,西藏林芝860000 [3]西藏林芝高山森林生态系统国家野外科学观测研究站,西藏林芝860000

出　　处：《西部林业科学》2022年第2期161-168,共8页Journal of West China Forestry Science

基　　金：西藏自治区教育厅项目“2019年西藏林芝森林生态站辐射基准站与冻土自动检测系统建设(502219001)”;科技部国家野外科学观测研究站(生态系统)运行补助项目“西藏林芝高山森林生态系统国家野外科学观测研究(2020-2025)”。

摘　　要：为了解色季拉山北坡林线过渡带不同海拔梯度、不同土层土壤养分变化和化学计量特征,以有效评价色季拉山急尖长苞冷杉林线过渡带土壤生态系统养分状况。以急尖长苞冷杉林线过渡带土壤为研究对象,采用方差分析及化学计量比等方法,参照全国第二次土壤普查分级标准,对不同季节林线过渡带不同海拔以及不同土层深度的土壤pH值和化学计量特征进行比较分析。结果显示:(1)急尖长苞冷杉林线过渡带土壤pH值为3.56~5.64,为酸性土壤;(2)不同季节土壤养分含量具有差异性,所有指标均表现为非生长季高于生长季;(3)除了非生长季C∶N随土深增加而升高、生长季P∶K随土深增加先降后升外,其余各化学计量比皆随土层深度增加而递减;(4)非生长季C∶N,生长季C∶P、N∶P、C∶K、N∶K、P∶K均随海拔升高而递增;非生长季C∶K、N∶K、P∶K均随海拔升高先降后升。可得结论:色季拉山急尖长苞冷杉林线过渡带表层土壤有机碳(SOC)、全氮(TN)含量整体较高,远高于全国及全球陆地土壤C∶N;研究区域土壤肥力状况良好,但相对受P、K限制。This study is to understand the changes and stoichiometric characteristics of soil nutrients in different altitude gradients and different soil layers in the timberline ecotone on the north slope of Sejila Mountain,so as to effectively evaluate the nutrient status of soil ecosystem in the timberline ecotone of Abies georgei var.smithii forest.Taking the soil in the timberline ecotone as the research object,using the methods of analysis of variance and stoichiometric ratio,and referring to the classification standard of the second national soil survey,the soil pH and stoichiometric characteristics of different altitudes and different soil depths in the transition zone of forest line in different seasons were compared and analyzed.The results showed that:(1)the pH of the soil in the transition zone of fir forest line was 3.56~5.64,which was acidic soil;(2)The content of soil nutrients was different in different seasons,and all indexes were higher in non growing season than in growing season;(3)Except that C∶N increased with the increase of soil depth in non growing season and P∶K first decreased and then increased with the increase of soil depth in growing season,the other stoichiometric ratios generally decreased with the increase of soil depth;(4)C∶N in non growing season,C∶P,N∶P,C∶K,N∶K and P∶K in growing season increased with the increase of altitude;In non growing season,C∶K,N∶K and P∶K decreased first and then increased with the increase of altitude.The contents of SOC and TN in the surface soil of the timberline ecotone of Abies georgei var.smithii forest in Sejila Mountain are generally high,which is much higher than the C∶N in the national and global land soil.The soil fertility in the study area is healthy,but relatively limited by P and K.

关 键 词：林线过渡带 化学计量特征 海拔 不同季节 色季拉山 急尖长苞冷杉 

分 类 号：S714[农业科学—林学]