青藏高原不同生境沙棘叶片及土壤碳、氮、磷的生态化学计量特征  

Ecological Stoichiometry Characteristics of Carbon,Nitrogen,and Phosphorus in Hippophae rhamnoides Leaves and Soil Across Different Habitats on the Qinghai⁃Tibet Plateau

作　　者：杨红 高文于 吕庆鑫 白有志 阮成江 丁健 孙宗玖[3] Yang Hong;Gao Wenyu;Lyu Qingxin;Bai Youzhi;Ruan Chengjiang;Ding Jian;Sun Zongjiu(Tibet Agricultural and Animal Husbandry University,Linzhi 860000,P.R.China;Dalian Minzu University;Xinjiang Agricultural University)

机构地区：[1]西藏农牧学院,林芝860000 [2]大连民族大学 [3]新疆农业大学

出　　处：《东北林业大学学报》2024年第8期110-119,共10页Journal of Northeast Forestry University

基　　金：西藏自治区项目-中央引导地方项目(XZ202201YD0025C);大连民族大学生物技术与资源利用国家重点实验室开放性课题(KF2023010、KF2024004);拉萨南北山造林主要树种培育示范中心建设(藏财科教指2023-17号)。

摘　　要：为掌握青藏高原低温区沙棘(Hippophae Linn)灌丛土壤养分分布格局及其生态化学计量特征,探究沙棘灌丛土壤养分固持能力及土壤养分限制类型。以青藏高原江孜沙棘、西藏沙棘、肋果沙棘和云南沙棘4种典型沙棘为对象,探讨不同类型沙棘叶片及非根土、根围土0<h≤20 cm土层的有机碳(SOC)、全氮(TN)、全磷(TP)、全钾(TK)质量分数及其生态化学计量特征。结果表明:4种生境沙棘非根土土壤含水量(SM)、土壤密度(SBD)、地上生物量、地下生物量均大于根围土。青藏高原低温区4种典型生境沙棘非根土及根围土0<h≤20 cm土层养分质量分数均维持在较高水平,非根土养分质量分数大于根围土。低海拔沙棘非根土具有较高的P固持潜力,随海拔高度增加,N元素限制程度逐渐降低。从沙棘叶片生态化学计量特征来看,高海拔地区沙棘(西藏沙棘、肋果沙棘)叶片有利于N、P、K的累积,符合“温度-植物生理假说”。从相关性分析来看,土壤养分之间及植物叶片养分之间相互耦合、相互制约,N、P元素在一定程度影响植物C的同化和土壤C的矿化,反之亦然。通过沙棘非根土和根围土养分质量分数及化学计量特征在不同海拔及土层间的分布状况进行初步判断,青藏高原低温区4种生境沙棘的生长发育均存在不同程度的N元素限制,但随海拔高度增加,N元素限制程度逐渐降低。To understand the nutrient distribution patterns and ecological stoichiometry characteristics of Hippophae rhamnoides shrubland soils in the cold regions of the Qinghai⁃Tibet Plateau,and to explore soil nutrient retention capacity and nutrient limitation types in H.gyantsensis,H.thibetana,H.neurocarpa,and H.yunnanensis,four typical H.rhamnoides species in the Qinghai⁃Tibet Plateau.Different types of H.rhamnoides leaves and organic carbon(SOC),total nitrogen(TN),total phosphorus(TP),and total potassium(TK)mass fractions of non⁃root soil,root zone soil(0<h≤20 cm),and ecological stoichiometry characteristics were investigated.The results showed that soil moisture content(SM),soil bulk density(SBD),above⁃ground biomass,and below⁃ground biomass of H.rhamnoides in four habitats on the Qinghai⁃Tibet Plateau are higher in non⁃root soil compared to root zone soil.The nutrient mass fractions in non⁃root soil and root zone soil(0<h≤20 cm)of H.rhamnoides in the cold regions of the Qinghai⁃Tibet Plateau are maintained at relatively high levels,with higher nutrient mass fractions observed in non⁃root soil compared to root zone soil.Non⁃root soil of H.rhamnoides at lower elevations exhibits high phosphorus retention potential,while nitrogen limitation decreases with increasing altitude.Regard⁃ing the ecological stoichiometry characteristics of H.rhamnoides leaves,species at higher altitudes(H.thibetana,H.neu⁃rocarpa)accumulate nitrogen,phosphorus,and potassium,consistent with the temperature⁃plant physiological hypothesis.Correlation analysis reveals mutual coupling and restriction between soil nutrients and plant leaf nutrients,with nitrogen and phosphorus elements influencing plant carbon assimilation and soil carbon mineralization to a certain extent,and vice versa.Preliminary assessment based on nutrient mass fractions and stoichiometric characteristics of non⁃root and root zone soils at different altitudes and soil layers indicates varying degrees of nitrogen limitation in the growth and d

关 键 词：沙棘 非根土 根围土 土壤养分 生态化学计量 

分 类 号：S714.5[农业科学—林学]