摘要
在祁连山冷龙岭南麓坡地进行不同海拔高度土壤(0～40(30)cm土层)和植被的整体双向移地实验,以探讨气候变化对主要物种和群落碳、氮特征的影响。结果表明,3 200 m的麻花艽移地至高海拔时,叶片碳、氮含量分别呈现出先增加后减少和一直增加的趋势,而碳/氮值下降明显。3 400 m的兰石草、珠芽蓼、垂穗披碱草、金露梅和鹅绒委陵菜5种植物大部分叶片碳、氮素含量及碳/氮呈现出随海拔增高而下降的趋势。3 600 m的矮嵩草、雪白委陵菜和重齿风毛菊3种植物叶片碳、氮含量及碳/氮在各海拔之间变化不明显。3 800 m的矮嵩草和矮火绒草的叶片碳、氮含量随海拔高度增加而增加,碳/氮下降。整个群落来讲碳含量随海拔升高而降低,氮含量和碳/氮比变化较小。研究发现,各群落和物种对移地的响应方式因物种组成、原生状态不同而存在差异;温度条件(以海拔升降模拟温度降升)对植被群落及主要植物叶片碳、氮含量和碳/氮比有一定影响,尤其是当高海拔稀疏植被移地到低海拔时,其叶片碳、氮和碳氮比与原生状况的植被群落及主要植物种相对变化较大。
Along the elevation gradients in the southern slope of Lenglongling,Qilian Mountains,we conducted a reciprocal translocation experiment on coherent quadrats of soil（0～40（30） cm） and turf,and analyzed responses of carbon and nitrogen of alpine dominant plant species and community to simulated climate change.The results showed that carbon contents of Gentiana straminea from 3 200 m increased and reached its peak at 3 600 m then declined,while its nitrogen contents were enhanced,and then its C∶N（carbon nitrogen ratio） declined significantly along the elevation hoisting.The carbon,nitrogen contents and C∶N of Lancea tibetica,Polygonum viviparum,Elymus nutans,Potentilla fruticosa,Potentilla anserina from 3 400 m showed the tendency of descending with altitude climbing.The carbon,nitrogen and C∶N of Kobresia humilis,Potentilla nivea,Saussurea katochaete from 3 600 m changed undetectably to translocation experiment.The contents of carbon and nitrogen of Kobresia humilis,Leontopodium nanum from 3 800 m increased,and C∶N descended with elevation rising.The carbon contents of community was enhanced,nitrogen and C∶N fluctuated little along with elevation rising.There were difference of response to reciprocal translocation experiment between plant species and community,due to species composition and primary location.The thermal factor（simulated warming from higher elevation to lower sites,vice versa,cooling） influenced the carbon,nitrogen and C∶N of dominated species and plant community.The carbon,nitrogen and C∶N of sparse vegetation fluctuated much more when transferred to lower elevation,because it was inhabited the maximum elevation of native species distribution.
出处
《西北植物学报》
CAS
CSCD
北大核心
2011年第4期788-794,共7页
Acta Botanica Boreali-Occidentalia Sinica
基金
国家自然科学基金项目(31070437)
国家重点基础研究发展计划(973计划)项目(2010CB833501)
关键词
祁连山冷龙岭南麓
移地实验
植物碳、氮
碳氮比
Southern Slope of Lenglongling
Qilian Mountain
translocation experiment
plant carbon and nitrogen
C∶N ratio
