摘要
植物功能性状能够反映植物对环境变化的响应,但是很少有研究同时考虑多个气候变化因子交互对植物功能性状的影响。基于氮添加(0 g·m^−2·a^−1和10 g·m^−2·a^−1)和干旱(减少66%生长季(5-8月)降水量)模拟实验,测量了呼伦贝尔草原5种优势植物的叶片形态学特征、叶片化学计量学特征以及植被高度等多个指标,探讨了呼伦贝尔草原植物对于土壤养分和水分变化的响应。结果表明,(1)干旱能够促进氮添加对土壤可利用氮特别是硝态氮含量的提升。(2)氮添加显著增加叶片N含量,降低叶片P含量,增加叶片氮磷比;干旱降低叶片N含量和叶片P含量,对叶片氮磷比影响不显著;植物叶片N、P含量受氮添加和干旱交互作用的显著影响,并在氮添加情况下施加干旱能够进一步增加P素对植物生长的限制作用。(3)氮添加处理下植物倾向于采取资源获取型策略,增加高度和比叶面积(SLA),降低叶片干物质含量(LDMC);干旱处理下植物倾向于资源保守型利用策略,降低高度和SLA,增加LDMC和叶片C含量;而植物高度、SLA、LDMC和叶片C含量不受氮添加和干旱交互作用的显著影响。研究表明,草地生态系统氮、水循环之间存在偶联关系,两者共同影响了植物养分吸收,决定植物叶片化学计量特征;而氮添加对植物资源利用策略影响更多的受到土壤水分调节。该研究强调在未来的气候变化研究中,需要同时考虑多个气候变化因子及其交互作用对植物功能性状的影响,并且需要考虑不同维度的功能性状的响应,才能更全面更准确地评估并预测生态系统功能的变化。
꞉Plant functional traits can reflect the responses of vegetation to environmental change,but few studies have considered its responses to the interactive effects of multiple climate change factors.Based on the simulated experiment of nitrogen(N)addition(0 and 10 g·m−2·a−1)and drought(66%precipitation reduction in growth season(May-August)),the leaf morphological characteristics,leaf chemometric characteristics and vegetation height of five dominant plants in Hulunbeier grassland were measured,and the responses of Hulunbeier grassland plants to soil nutrient and water changes were discussed.The results showed that:(1)Drought could promote soil available N,especially NO3−1-N.(2)Nitrogen addition significantly increased N content,decreased P content and consequently increased N:P ratio of leaves;drought reduced foliar N and P contents,but had no significant effect on foliar N:P ratio;N and P contents of plant leaves were significantly affected by the interaction of nitrogen addition and drought,and the application of drought under the condition of nitrogen addition could further increase P limitation for plant growth.And(3)plants tended to adopt resource acquisition strategy through increasing plant height and specific leaf area(SLA),and reducing dry matter content(LDMC)under the treatment of nitrogen addition,and tended to adopt resource conservation strategy via reducing plant height and SLA and increasing LDMC and leaf C content under the treatment of drought,while plant height,SLA,LDMC and leaf C content are not affected by the interaction of nitrogen addition and drought.The results show that there was a coupling relationship between nitrogen and water cycle in grassland ecosystem,which together affected the plant nutrient absorption and determined the stoichiometric characteristics of plant leaves,while the effect of nitrogen addition on plant resource utilization strategy was more regulated by soil water.This study emphasizes that future researches should simultaneously consider the impacts of multi
作者
周一平
张玉革
马望
梁潇洒
马欣雨
王正文
ZHOU Yiping;ZHANG Yuge;MA Wang;LIANG Xiaosa;MA Xinyu;WANG Zhengwen(School of Environment,Shenyang University,Shenyang 110044,China;Erguna Forest-Steppe Ecotone Research Station,Institute of Applied Ecology,Chinese Academy of Sciences,Shenyang 110016,China)
出处
《生态环境学报》
CSCD
北大核心
2020年第1期41-48,共8页
Ecology and Environmental Sciences
基金
国家重点研发专项项目（2016YFC0500602-2）
关键词
氮添加
减水
交互作用
植物功能性状
养分利用策略
꞉nitrogen addition
water reducing
interaction
plant functional traits
nutrient utilization strategy
