东北地区落叶松新鲜针叶凋落物碳氮磷化学计量特征对环境变化的响应  

Carbon,nitrogen,and phosphorus stoichiometry of recently senesced larch leaves in response to environmental factors across an entire growing season

作　　者：李汶倬 高扬[2] 杨柳 蒋治岩 王秀伟[1] LI Wen-zhuo;GAO Yang;YANG Liu;JIANG Zhi-yan;WANG Xiu-wei(Ministry of Education Key Laboratory of Sustainable Forest Ecosystem Management,School of Forestry,Northeast Forestry University,Harbin 150040,China;College of Chemistry,Chemical Engineering and Resource Utilization,Northeast Forestry University,Harbin 150040,China)

机构地区：[1]东北林业大学林学院,森林生态系统可持续经营教育部重点实验室,哈尔滨150040 [2]东北林业大学化学化工与资源利用学院,哈尔滨150040

出　　处：《生态学杂志》2020年第9期2832-2841,共10页Chinese Journal of Ecology

基　　金：国家重点研发计划课题(2018YFC0507003);国家自然科学基金项目(31670476);中央高校基本科研业务费专项(2572019BA15,2572019CP09)资助。

摘　　要：为了解新鲜叶凋落物碳(C)、氮(N)、磷(P)化学计量特征对生长季环境因子变化的响应规律,揭示落叶松人工林生态系统养分循环过程,本研究以东北地区4个不同纬度地点的落叶松人工林新鲜针叶凋落物为对象,分析了针叶凋落物C、N和P含量与生长季累积温度、累积降水量和土壤养分累计变化量的关系。结果表明:4个地点间落叶松针叶凋落物C、N和P含量变化范围分别为429~497、7.94~16.27和1.04~2.49 mg·g^-1。随生长季累积温度升高,落叶松针叶凋落物C、N含量升高,P含量降低,C∶P和N∶P升高;随生长季累积降水量增加,落叶松针叶凋落物C、N含量降低,C∶N升高,C∶P和N∶P降低。凉水、帽儿山、露水河和草河口生长季土壤全氮变化量分别为(-0.84±0.27)、(-0.42±0.07)、(0.04±0.01)和(1.44±0.01)g·kg^-1,土壤全磷变化量分别为(0.98±0.04)、(-0.24±0.05)、(-0.30±0.06)和(-0.95±0.05)g·kg^-1。4个地点的人工林中,落叶松普遍受到N限制,生长季累积温度较高的地点落叶松受到N限制的程度较低,累积降水量越多落叶松越容易受到N限制。在N限制得到缓解或程度较低的地点,落叶松针叶凋落物的C含量更高,P的利用效率也相应提高。因此,在东北地区落叶松人工林的经营过程中,应考虑生长季温度和降水量的变化,并关注土壤与落叶松N含量的动态变化,及时调整养分管理措施,保证落叶松正常生长。We collected recently senesced leaf litter from larch plantations across a latitudinal gradient in Northeast China to investigate the responses of carbon(C),nitrogen(N),and phosphorus(P)stoichiometry to environmental factors across an entire growing season and to assess potential nutrient limitation.Concentrations of litter C,N and P ranged 429-497 mg·g^-1,7.94-16.27 mg·g^-1,and 1.04-2.49 mg·g^-1,respectively.The C and N concentrations as well as the ratios of C∶P and N∶P increased with increasing accumulated temperature and decreased with increasing accumulated precipitation.The P concentration decreased with increasing accumulated temperature,whereas C∶N ratio increased with increasing accumulated precipitation.The accumulated changes of soil total N contents were(-0.84±0.27),(-0.42±0.07),(0.04±0.01),and(1.44±0.01)g·kg^-1,while the accumulated changes of soil total P contents were(0.98±0.04),(-0.24±0.05),(-0.30±0.06),and(-0.95±0.05)g·kg^-1 in Liangshui,Maoershan,Lushuihe,and Caohekou along a decreased latitudinal gradient.Nitrogen limitation commonly occurred in larch plantations across the four sites.The degree of N limitation decreased with increasing accumulated temperature and increased with increasing accumulated precipitation.When N limitation was alleviated,C concentrations were higher,and P use efficiency increased.Therefore,accumulated temperature and precipitation can inform management decisions related to plantation fertilization.

关 键 词：落叶松人工林 新鲜叶凋落物 化学计量学 温度 降水量 土壤养分 

分 类 号：S718.5[农业科学—林学]