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SCI论文目录 |
5年模拟增温后矮嵩草草甸群落结构及生产量的变化 |
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| 出 版 社：草地学报 第12卷 第3期 |
| 发表时间：2004年 9月 |
| 台 站：
海北高寒草甸生态系统定位研究站
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| 作 者：李英年,赵亮,赵新全,周华坤 |
| 点 击 率：6130 |
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| 关 键 字：关键词:草原学;模拟增温;矮嵩草草甸;暖室;群落结构 |
| 摘 要：摘要:5年模拟增温后观察表明,植物生长期4～9月暖室内10cm、20cm地下土壤平均增温1.86℃,10cm、20cm地上空气平均增温1.15℃,地表0cm平均增温1.87℃,且增温在植物生长初期大于生长末期及枯黄期。在模拟增温初期年生物量比对照高,增温5年后生物量反而有所下降。增温使禾草类植物种增加,杂草减少。从表面来看,增温可使植物生长期延长,利于增大生物量,实际受热效应作用,植物发育生长速率加快,植物成熟过程提早,生长期反而缩短,加之玻璃纤维的存在使暖室内外温度交换减缓,减少了温度日变化,限制干物质积累,终久导致生物量减少。这说明小气候的作用,环境条件诱发土壤结构变化,植被的种群结构也随之改变,甚至出现演替的过程,全球变暖不仅对植物的生物生产力影响较大,而且对植被类型的演替有着不可忽视的作用。 |
| 关 键 字(英文)：Keywords:Grasslandscience;Mimicairtemperatureincrease;Kobresiahumilismeadow;Greenhouse;Com-munitystructure |
| 摘 要(英文)：Abstract:Amimic5-yeartemperatureincreasedinagreenhouseraisedthesoiltemperatureof10and20cmdepth1.86℃higherthanthatintheopen,the10and20cmabovegroundairtemperature1.15℃higher,andthesoilsurfacetemperature1.87℃higherthanthatintheopenrespectively,Theextentoftemperaturein-creasewasgenerallygreaterintheearlyplantgrowingseasonthaninthelaterstageandtheplantwitheringpe-riod.Theresultshowedthatinthefirstfewyearsofthe5-yearexperiment,theyearlybiomassfromthegreen-houseisweightierthanthatofthecontrolintheopen.However,afterthe5-yearperiod,theyearlybiomassformthegreenhousedecreasedandbecamelessthanofthecontrol.Thoughhighertemperatureincreasedthenumberofgrassspecies,preventedweedsfromteemingtheland,andapparentlyextendedtheplantgrowingperiod,andraisedthebiomass,theheatacceleratedthegrowthandmaturingofplants,thusshorteningthegrowingperiodactually.Moreover,theglassofthegreenhouseretardedthefluctuationoftemperatureofday-timeandthenighttime,andrestrictedtheaccumulationofdrymatter.allthisleadstothedecreaseofbiomassinthegreenhouse.Themicro-climaticchangeofsoilstructurewhichalsochangesthestructureoftheplantspeciesandleadstothespeciessuccessionprocess.Consequently,globalwarmingnotonlyaffectstheplantpro-ductivity,butthesuccessionofplanttypesaswell. |
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