西北干旱区荒漠植物叶片和细根碳、氮、磷化学计量特征  

Carbon,nitrogen and phosphorus stoichiometry in leaves and fine roots of desert plants in arid region of Northwest China

作　　者：陈壹铭 单立山[1] 马静 王红永 解婷婷 杨洁 马丽 CHEN Yiming;SHAN Lishan;MA Jing;WANG Hongyong;XIE Tingting;YANG Jie;MA Li(College of Forestry,Gansu Agricultural University,Lanzhou 730070,China)

机构地区：[1]甘肃农业大学林学院,兰州730070

出　　处：《生态学报》2024年第9期3648-3659,共12页Acta Ecologica Sinica

基　　金：甘肃农业大学青年导师扶持基金(GAU-QDFC-2022-08);国家自然科学基金(32160253);甘肃省重点研发计划项目(22YF7FA117);甘肃省优秀博士生项目(23JRRA1452)。

摘　　要：植物的叶片和细根是植物地上部分和地下部分最重要的营养器官,其碳(C)、氮(N)、磷(P)化学计量特征反映了植物的养分限制状况及叶片与细根间的协同作用,开展叶片与细根化学计量关系的研究,对认识植物养分利用策略及元素间平衡关系有重要意义。对西北干旱区21种荒漠植物叶片与细根C、N、P含量进行了测定,分析了C、N、P含量及其计量比在不同生活型及不同器官间的关系。结果表明:1)西北干旱区荒漠植物叶片与细根C含量相对稳定,叶N、P含量高于细根,说明在干旱生境中,植物对养分的分配侧重于地上部分,以完成其正常的生命活动;叶片与细根的N∶P无显著差异,有明显的保守性,表明植物地上与地下部分养分吸收策略与分配规律具有一致性;2)不同生活型植物叶片和细根的C、N、P含量及C∶N、C∶P存在显著差异,灌木与禾草具有较高的C∶N和C∶P,杂类草具有较高的N、P含量,说明灌木与禾草倾向于保守型养分适应策略,杂类草倾向于快速生长的资源竞争策略;3)21种荒漠植物叶片与细根N、P含量间均存在显著的正相关关系,表明西北干旱区荒漠植物体内N、P元素间存在相互作用;4)植物叶片与细根间C、N、P含量及C∶N、C∶P存在等速生长关系,表明植物光合产物和养分在地上与地下部分间的分配具有平行的比例关系,但这种关系受生活型影响。上述结果表明西北干旱区不同生活型植物在恶劣生境中存在不同的养分适应策略,且地上与地下部分的养分利用策略及分配规律存在协同作用,这为进一步认识西北干旱区荒漠植物的养分利用策略提供了试验基础。Leaves and fine roots play a crucial role as vegetative organs in both the aboveground and underground parts of plants.The stoichiometric characteristics of carbon(C),nitrogen(N),and phosphorus(P)in these organs reflect the strategies of nutrient adaptation and the balance of elements.In this study,we examined the C,N,and P content as well as the C∶N,C∶P,and N∶P ratios in leaves and fine roots of 21 desert plants in arid region of Northwest China.The plant species were categorized into three life forms:shrubs,forbs,and grasses.We investigated the correlation and differences in C,N,and P contents and their ratios between leaves and fine roots,as well as among the three life forms.Our findings revealed the following:1)The C content of leaves and fine roots in desert plants of the northwest arid region remained relatively stable,while the N and P contents of leaves were higher compared to fine roots.This suggests that in arid habitats,plants allocate nutrients to their aboveground parts to carry out essential life activities.Moreover,there was no significant difference in N∶P between leaves and fine roots,indicating a consistent nutrient absorption strategy and distribution pattern between the above⁃ground and underground parts of plants.2)The significant differences were observed in the content of C,N,and P,as well as in the ratios of C∶N and C∶P,among the leaves and fine roots of various life forms.Shrubs and grasses exhibited higher C∶N and C∶P ratios,suggesting their inclination towards conservative nutrient adaptation strategies.On the other hand,forbs displayed higher N and P content,indicating their preference for fast⁃growing resource competition strategies.3)The study revealed a noteworthy positive correlation between the N and P contents in both leaves and fine roots of 21 desert plants.This finding suggests the presence of an interaction between N and P elements in desert plants within the arid region of Northwest China.4)The C,N,P contents and C∶N,C∶P ratios between leaves and fin

关 键 词：生态化学计量 叶片 细根 生活型 西北干旱区 荒漠植物 

分 类 号：Q948[生物学—植物学]