低水位增加灌木多样性和生物量但降低土壤有机碳含量:以鄂西南贫营养泥炭地为例  

Lower water table increase shrub plant diversity and biomass but decrease soil organic carbon content:A case study of oligotrophic peatland in the Southwestern Hubei Province

作　　者：吴浩 余玉蓉 王佳钰 赵媛博 高娅菲 李小玲 卜贵军[1,2] 薛丹 吴林[1,2] Hao Wu;Yurong Yu;Jiayu Wang;Yuanbo Zhao;Yafei Gao;Xiaoling Li;Guijun Bu;Dan Xue;Lin Wu(Hubei Key Laboratory of Biological Resources Conservation and Utilization,Enshi,Hubei 445000;College of Forestry and Horticulture,Hubei Minzu University,Enshi,Hubei 445000;Institute of Chinese Medicinal Materials,Hubei Academy of Agricultural Sciences,Enshi,Hubei 445000;Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization,Chengdu Institute of Biology,Chinese Academy of Sciences,Chengdu 610041)

机构地区：[1]生物资源保护与利用湖北省重点实验室,湖北恩施445000 [2]湖北民族大学林学园艺学院,湖北恩施445000 [3]湖北省农业科学院中药材研究所,湖北恩施445000 [4]中国科学院成都生物研究所山地生态恢复与生物资源利用院重点实验室,成都610041

出　　处：《生物多样性》2023年第3期30-41,共12页Biodiversity Science

基　　金：国家自然科学基金(32260303,41867042)。

摘　　要：地下水位变化对泥炭地的植被组成及多样性具有明显的调控作用,从而可能会深刻改变泥炭地的储碳潜力。目前,有关泥炭地植物多样性和土壤有机碳含量对水位波动的响应还存在较大争议,且有关亚热带贫营养泥炭地地下水位对植物多样性及生物量与土壤有机碳含量影响的研究鲜有报道。本研究选择鄂西南贫营养泥炭地为研究对象,调查了4个地下水位梯度(-4 cm、-8 cm、-12 cm、-20 cm)下的植被组成、多样性、生物量及土壤有机碳含量,以探究不同水位梯度对鄂西南贫营养泥炭地植物多样性、生物量及土壤有机碳含量的影响。结果表明:(1)地下水位下降,土壤含水量、土壤有机碳含量和总酚含量显著降低,而溶解氧含量显著增加(P<0.05)。并且,低水位(-20 cm)处土壤有机碳含量是高水位(-4 cm)处土壤有机碳含量的72%。(2)地下水位显著改变鄂西南贫营养泥炭地物种组成,随着地下水位下降,灌木物种数量增加,且以浅根系的杜鹃花科和蔷薇科植物为主。(3)总体上,随着地下水位的降低,灌木多样性呈现显著增加的趋势(P<0.05),而草本植物多样性变化不显著。(4)地下水位对植被地上总体生物量影响不显著,但随地下水位的降低,灌木生物量极显著增加(P<0.01)、草本生物量显著增加(P<0.05),而苔藓生物量降低。本研究表明,较高的地下水位是维持鄂西南贫营养泥炭地土壤有机碳含量的关键,维管植物多样性的提升并不能增加该泥炭地的固碳潜力。Aim:The change of water table level has an obvious causative effect on the vegetation composition and diversity of peatlands,which may profoundly change the carbon sequestration potential of peatlands.However,the exact responses of the diversity of vegetation and soil organic carbon in peatland have to water table fluctuations are still controversial.In addition,there are few reports on the effects of water table level on plant diversity,biomass and soil organic carbon in oligotrophic peatlands in subtropical regions.Methods:Soil organic carbon content,species diversity and vegetation biomass of different groundwater levels were compared by one-way ANOVA.Significant difference in species diversity and biomass of plant community were analyzed by LSD multiple comparison method(P=0.05).Linear correlation analysis was used to compare the correlation among water level,oxygen content,Sphagnum moss and shrub biomass.Results:(1)With a decrease in level of the water table,soil water content,soil organic carbon content and polyphenol content all decreased significantly,while dissolved oxygen increased significantly(P<0.05).Moreover,soil organic carbon at the low-water table(-20 cm)was 72%of that at the high-water table(-4 cm).(2)Water table significantly changed the plant species composition of oligotrophic peatland in the Southwestern Hubei Province.With a decrease in level of the water table,the number of shrub species increased,and the shallow-rooted Ericaceae and Rosaceae were the dominant shrubs.(3)Overall,shrub diversity showed a significant increase with the decrease of water table(P<0.05),while herbaceous diversity showed no significant change.(4)Water table had no significant effect on the total aboveground biomass of vegetation.However,with the decrease of water table,shrub biomass(P<0.01)and herbaceous biomass(P<0.05)significantly increased,while moss biomass decreased.Conclusion:This study shows that a higher water table is a key factor to maintain soil organic carbon content in oligotrophic peatlands in the So

关 键 词：泥炭藓湿地 地下水位 植物多样性 生物量 土壤有机碳 

分 类 号：Q948.113[生物学—植物学]