摘要
以高寒沼泽草甸为研究对象,采用开顶室增温小室进行增温模拟实验,设置CK(对照点)、T_1(增温1.5—2.5℃)、T_2(增温3—5℃)3种处理,研究了短期增温对高寒沼泽草甸土壤活性有机碳库及生物量生产的影响。结果表明:(1)T_1增温显著促进土壤微生物量碳(MBC)的生成,T_2增温幅度过大,抑制了微生物的活性,导致这种促进效果在T_2内不显著。(2)T_1, T_2增温均使得0—20 cm土层土壤有机碳(SOC)含量降低, T_1增温促进20—30 cm土层土壤有机碳(SOC)的生成,但这种促进效果在T_2内并不显著。(3)T_1, T_2增温均使得0—20 cm土层土壤溶解性有机碳(DOC)含量降低, 20—30cm土层土壤溶解性有机碳(DOC)含量无明显变化。(4)模拟增温促进了长江源高寒沼泽草甸地上生物量的生成,并且增温幅度越大地上生物量增加越多。T_1增温促进了地下生物量的生成,T_2增温幅度过大,对地下生物量随温度上升而增加的这种促进作用有所抑制。(5)土壤有机碳(SOC),土壤微生物量碳(MBC),土壤溶解性有机碳(DOC)三者碳组分之间均呈显著正相关,表明土壤有机碳(SOC)的变化在一定程度上制约的土壤微生物量碳(MBC)与土壤溶解性有机碳(DOC)的变化。
This study investigated the short-term effects of simulated warming on soil organic carbon pools and plant biomass in alpine swamp meadow.Open-top chambers were used to simulate climate warming.Three treatments were simulated in our experiment:CK(control),T1(temperature increased by1.5-2.5℃),and T2(temperature increased by 3-5℃).The results are as follows.(1)The soil microbial biomass carbon(MBC)in T1 plots increased significantly.In T2 plots,the soil microbial activity might be inhibited due to the over rising temperature,thus the soil MBC was not affected obviously.(2)Soil organic carbon(SOC)at 0-20 cm soil depth in the warming plots(T1,T2)was significantly higher than that in CK plots.The SOC at 20-30cm soil depth increased obviously in T1 plots,but this positive effect was not significant in T2 plots.(3)Warming(T1,T2)increased dissolved organic carbon(DOC)at 0-20cm soil depth but the DOC at 20-30cm soil depth was not significantly influenced..(4)Warming(T1,T2)showed obvious positive effects on aboveground biomass(AGB),and the greater increase in temperature,the more increase in above-ground biomass.Underground biomass(BGB)increased in T1 plots,in contrast,the BGB tended to be inhibited in T2 plots.(5)There were significant positive correlations between SOC,MBC and DOC,indicating that the changes in soil MBC and DOC were restricted by the variations in soil SOC.
作者
奚晶阳
白炜
尹鹏松
刘永万
XI Jingyang;BAI Wei;YIN Pengsong;LIU Yongwan(School of Environmental and Municipal Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China)
出处
《生态科学》
CSCD
2019年第1期92-101,共10页
Ecological Science
基金
国家自然科学基金(41563005)
兰州交通大学青年科学基金(2015013)
关键词
长江源区
模拟增温
高寒沼泽草甸
土壤微生物量碳
土壤溶解性有机碳
生物量
the headwaters region of the Yangtze River
simulated warming
alpine swamp meadow
soil microbial biomass carbon
soil dissolved organic carbon
biomass
