干旱区生态环境知识资源中心(Arid): 模拟CO_2升高及降水变化对红砂碳氮特征的影响

Arid

	模拟CO_2升高及降水变化对红砂碳氮特征的影响
其他题名	Effects of simulated elevated CO_2concentration and precipitation change on carbon and nitrogen characteristics of Reaumuria soongorica
	刘晟彤 1; 种培芳 1; 姬江莉 1; 曾继娟 2
来源期刊	草业学报
ISSN	1004-5759
出版年	2018
卷号	27 期号:5 页码:73-84
中文摘要	为探讨荒漠植物红砂根、茎、叶在CO_2升高与降水变化条件下的碳氮含量及分配特征,以当年生民勤红砂为试验材料,利用开顶式CO_2控制气室,研究了350、550及700mumol·mol~(-1)3种CO_2浓度和降水减少30%(-W_2)、减少15%(-W_1)、自然降水(W0)、增加15%(+W_1)和增加30%(+W_2)5个降水变化下红砂根、茎、叶的有机碳、全氮含量、C/N及有机碳和全氮积累(吸收)量。结果表明:1)相同降水条件下,CO_2浓度升高使根、茎、叶有机碳含量显著增加,全氮含量显著减少;在-W_2降水量和700mumol·mol~(-1) CO_2浓度时根有机碳含量增幅最大(13.33%),在+W_1降水量和700mumol·mol~(-1) CO_2浓度时叶全氮含量降幅最大(56.31%);CO_2浓度升高使红砂根、茎、叶C/N显著升高,对有机碳、全氮积累(吸收)量影响显著。2)相同CO_2浓度条件下,降水增加对根、茎、叶有机碳含量及全氮含量影响显著;550mumol·mol~(-1) CO_2浓度和+W_2降水量时叶有机碳含量增幅最大(11.56%),700 mumol·mol~(-1) CO_2浓度和+W_2降水量时叶全氮含量降幅最大(35.31%);降水量对红砂根、茎、叶的C/N及有机碳、全氮积累量影响显著。3)在CO_2浓度升高与降水变化下,红砂有机碳含量在根中最高,全氮含量在叶中最高, C/N在根中最大,红砂有机碳、全氮积累(吸收)量在叶中最高。综上所述,未来CO_2浓度升高及降水改变的情况下,红砂生长情况取决于CO_2浓度与降水量的协同作用对有机碳、全氮含量的影响,CO_2浓度升高会在一定程度上减缓干旱对红砂碳氮吸收及利用的抑制作用,在湿润条件下能有效地增强红砂对碳氮的吸收及利用能力。
英文摘要	Atmospheric CO_2concentrations are predicted to increase from approximately 350mumol·mol~(-1)today to over 700mumol·mol~(-1)in the late 21st century.In the future,elevated CO_2levels are likely to have profound effects on precipitation.This change would seriously affect the desert ecosystem,altering the carbon and nitrogen allocations of desert plants and so leading to changes in ecosystem structure and function.Although many studies have examined the effects of precipitation and CO_2,the interactions between precipitation changes and CO_2in desert plants have attracted little attention to date.In order to assess the possible effect of global climate change on desert ecosystems,apot experiment was conducted to study the interaction of elevated CO_2concentrations and changing precipitation with organic carbon,total nitrogen,C/N,organic carbon accumulation(absorption), and total nitrogen accumulation(absorption)in the roots,stems and leaves of Reaumuria soongorica, a dominant species on desert steppe in the arid regions of China.The main experiment included three CO_2 concentrations(350,550and 700mumol·mol~(-1))and five precipitation conditions(natural precipitation as control [W0],precipitation minus 30% [-W_2],precipitation minus 15% [-W_1],precipitation plus 15% [+ W_1],and precipitation plus 30% [+W_2]).The main results are as follows:1)At the same precipitation treatment, organic carbon in root,stem and leaf were significantly increased and total nitrogen decreased by elevated CO_2.The rise of organic carbon contents in roots was highest at 13.33%under 700mumol·mol~(-1) CO_2concentration and-W_2precipitation.Total nitrogen contents in leaves were lowest at 56.31% under 700mumol· mol~(-1) CO_2concentration and+W_1precipitation.C/N,organic carbon and total nitrogen accumulation(absorption) in root,stem and leaf were significantly increased by elevated CO_2.2)At the same CO_2concentrations, organic carbon and total nitrogen in roots and stems significantly increased with raised precipitation levels.The largest increase in organic carbon in leaves was 11.56% under+W_2precipitation and 550mumol·mol~(-1) CO_2 concentration.The largest decrease in total nitrogen in leaves was 40.16% under precipitation+W_2and 700 mumol·mol~(-1) CO_2concentration.C/N,organic carbon and total nitrogen accumulation(absorption)in root, stem and leaf were affected significantly by precipitation.3)Under the interactive effects of elevated CO_2and changing precipitation conditions,organic carbon contents and C/N were allocated mostly to roots,total nitrogen, organic carbon accumulation and total nitrogen accumulation(absorption)mostly to leaves.These results suggest that in the future,with CO_2concentration and precipitation changes,the growth states of R.soongorica will be decided by the interactive effects of CO_2concentration and precipitation changes on carbon and nitrogen. Elevated CO_2concentration can relieve the inhibition of drought on the carbon and nitrogen absorbed and used of R.soongorica,and moist conditions can reinforce the impact of these elements.
中文关键词	CO_2浓度升高 ; 降水变化 ; 有机碳 ; 全氮 ; 红砂
英文关键词	elevated CO_2concentration precipitation change organic carbon total nitrogen Reaumuria soongorica
语种	中文
国家	中国
收录类别	CSCD
WOS类目	FORESTRY
WOS研究方向	Forestry
CSCD记录号	CSCD:6240350
来源机构	甘肃农业大学
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/237358
作者单位	1.甘肃农业大学林学院, 兰州, 甘肃 730070, 中国; 2.宁夏林业研究院股份有限公司, 银川, 宁夏 750000, 中国
推荐引用方式 GB/T 7714	刘晟彤,种培芳,姬江莉,等. 模拟CO_2升高及降水变化对红砂碳氮特征的影响[J]. 甘肃农业大学,2018,27(5):73-84.
APA	刘晟彤,种培芳,姬江莉,&曾继娟.(2018).模拟CO_2升高及降水变化对红砂碳氮特征的影响.草业学报,27(5),73-84.
MLA	刘晟彤,et al."模拟CO_2升高及降水变化对红砂碳氮特征的影响".草业学报 27.5(2018):73-84.