喀斯特峰丛洼地3个建群树种“植物-凋落物-土壤”系统氮同位素特征  

Nitrogen isotope characteristics of"plant-litter-soil"system of three constructive tree species in Karst peak-cluster depression

作　　者：吴凤婵 蔡国俊 李安定[1] 张红玉[4] 张丽敏[3] 彭熙[3] WU Fengchan;CAI Guojun;LI Anding;ZHANG Hongyu;ZHANG Limin;PENG Xi(Guizhou Institute of Biology,Guizhou Academy of Sciences,Guiyang,Guizhou 550009,China;College of Environment&Ecology,Hunan Agricultural University,Changsha,Hunan 410128,China;Guizhou Institute of Mountain Resources,Guizhou Academy of Sciences,Guiyang,Guizhou 550001,China;School of Life Sciences,Guizhou Normal University,Guiyang,Guizhou 550025,China)

机构地区：[1]贵州科学院贵州省生物研究所,贵州贵阳550009 [2]湖南农业大学环境与生态学院,湖南长沙410128 [3]贵州科学院贵州省山地资源研究所,贵州贵阳550001 [4]贵州师范大学生命科学学院,贵州贵阳550025

出　　处：《贵州师范大学学报（自然科学版）》2024年第1期12-18,共7页Journal of Guizhou Normal University：Natural Sciences

基　　金：贵州省重大基础研究项目(黔科合JZ字[2014]200208);贵州省自然科学基金项目(黔科合基础[2018]1410);贵州科技计划项目(黔科合支撑[2022]一般200,黔科合平台人才[2021]5624号)。

摘　　要：以喀斯特峰丛洼地3种常见次生林及其建群树种为研究对象,测定3种林分建群种的不同器官及凋落物、土壤的氮含量及氮同位素丰度值(δ^(15)N),探讨植物-凋落物-土壤氮含量及稳定氮同位素组成变化及内在联系。结果显示:3种次生林建群种植物中叶片氮含量最高,茎的氮含量最低,3种次生林建群树种叶片氮含量均显著高于掉落物和土壤氮含量,0~30 cm土壤氮含量显著高于30~90 cm土壤氮含量,土壤养分主要集中于表层土壤;白栎、栓皮栎和光皮桦器官中δ^(15)N变化范围分别为-2.82‰~14.94‰、-1.37‰~9.35‰和-4.39‰~26.06‰,3种建群种器官间氮同位素组成均表现出显著差异(P<0.05);3种建群种群落表层土壤δ^(15)N差异显著,3种林分中0~30 cm土壤δ^(15)N均显著低于30~60 cm和60~90 cm的土壤,δ^(15)N可能是这些群落土壤氮循环过程中的敏感指标,光皮桦叶片氮含量略大于白栎和栓皮栎,光皮桦林土壤表层δ^(15)N大于白栎林和栓皮栎林,光皮桦可能比白栎和栓皮栎更为适应喀斯特生境。In this study,three common secondary forests and their constructive tree species in Karst peak-cluster depression were used to determine the nitrogen content and nitrogen isotope abundance of different organs,litter and soil.The changes and internal relations of plant-litter-soil nitrogen content and stable nitrogen isotope composition were discussed.The results showed:Among the three secondary forest constructive species,the leaf nitrogen content was the highest,the stem nitrogen content was the lowest,and the leaf nitrogen content was higher than the litter and soil nitrogen content of the three secondary forest constructive species.The soil nitrogen content of 0~30 cm was significantly higher than that of 30~90 cm,and the soil nutrients were mainly concentrated in the surface soil.The variation ranges ofδ^(15)N in the organs of Quercus fabrei,Quercus variabilis and Betula luminifera were-2.82‰~14.94‰,-1.37‰~9.35‰and-4.39‰~26.06‰,respectively.There were significant differences in nitrogen isotope composition among the three constructive species(P<0.05).There were significant differences inδ^(15)N of different tree species stands.0~30 cm soilδ^(15)N values in three stands were significantly lower than those in 30~60 cm and 60~90 cm soils.δ^(15)N may be a sensitive index in the process of soil nitrogen cycle under these communities.The leaf nitrogen content of Betula luminifera was slightly higher than that of Quercus fabrei and Quercus variabilis,and the surface soil nitrogen content of Betula luminifera forest was also higher than that of Quercus fabrei forest and Quercus variabilis forest.Betula luminifera may be more adapted to Karst habitat than Quercus fabrei and Quercus variabilis.

关 键 词：氮同位素 植物-凋落物-土壤 生态策略 适应机制 喀斯特峰丛洼地 

分 类 号：Q14[生物学—生态学] S154[生物学—普通生物学]