黄河源区建植19年人工草地生物结皮CO_(2)通量与叶绿素荧光参数的变化  

Changes of CO_(2) Fluxes and Chlorophyll Fluorescence Parameters of Biological Soil Crusts in a 19-year Artificial Grassland in the Source Zone of the Yellow River

作　　者：孙华方 李希来[1] 李成一[1] 张静[1] 林春英[1,2] 金立群[1,3] 杨鑫光 SUN Hua-fang;LI Xi-lai;LI Cheng-yi;ZHANG Jing;LIN Chun-ying;JIN Li-qun;YANG Xin-guang(College of Agriculture and Animal Husbandry, Qinghai University, Xining, Qinghai Province 810016, China;Qinghai Province Weather Modification Office, Xining, Qinghai Province 810001, China;Grassland station of Huangyuan County, Xining, Qinghai Province 812100, China;College of Ecological Environment and Resources, Qinghai University for Nationalities, Xining, Qinghai Province 810007, China)

机构地区：[1]青海大学农牧学院,青海西宁810016 [2]青海省人工影响天气办公室,青海西宁810001 [3]湟源县草原站,青海西宁812100 [4]青海民族大学生态环境与资源学院,青海西宁810007

出　　处：《草地学报》2021年第5期894-903,共10页Acta Agrestia Sinica

基　　金：青海省科技厅项目(2020-ZJ-904);国家自然科学基金项目(31872999);三江源国家公园联合研究专项(LHZX-2020-08);高等学校学科创新引智计划资助(D18013)项目;教育部长江学者和创新团队发展计划(IRT_17R62)资助。

摘　　要：为了解黄河源人工草地不同类型生物结皮和植被群落CO_(2)释放和固定的变化特征,并探讨二者的影响因子,本文通过调查黄河源建植19年人工草地不同类型生物结皮CO_(2)通量和植被土壤特征变化发现:藻和地衣结皮CO_(2)通量均显著小于苔藓结皮(10.58μmol·m^(-2)·s^(-1))(P<0.05);苔藓结皮对应的植被群落CO_(2)通量(11.55μmol·m^(-2)·s^(-1))显著低于藻和地衣结皮(P<0.05);藻和地衣结皮下的土壤CO_(2)通量显著大于苔藓结皮(约2倍,P<0.05)。苔藓结皮叶绿素初始荧光参数F0(Minimal Fluorescence)和最大荧光参数Fm(Maximal Fluorescence)均最大;藻和苔藓结皮的PSⅡ最大光化学量子产量Fv/Fm(Optimal/Maximal Quantum Yield of PSⅡ)均高于地衣结皮。CO_(2)通量和叶绿素荧光参数的主要影响因子相似,均与禾本科高度、土壤铵态氮含量正相关,与pH负相关。因此,在研究草地碳平衡过程中应充分考虑生物结皮的贡献,同时需注意不同类型的生物结皮的CO_(2)通量和叶绿素荧光参数的差异变化。To understand the variation of CO_(2)release and carbon fixation in different BSCs and vegetation communities in artificial grassland,and to explore the factors influencing CO_(2)release and photosynthesis of BSCs,we measured CO_(2)fluxes and chlorophyll fluorescence parameters of different BSCs in a 19-year-old artificial grassland,vegetation and soil characteristics were also investigated at the same time.The results showed that CO_(2)flux of algal and lichen crusts was significantly lower than that of moss(10.58μmol·m^(-2)·s^(-1))(P<0.05).The CO_(2)flux of the vegetation community was 11.55μmol·m^(-2)·s^(-1) in moss crust stage,which was significantly lower than that in algal and lichen crusts(P<0.05).The CO_(2)flux of the soil covered by algae and lichen crusts was significantly higher than that of moss crusts in soil CO_(2)fluxes test(about 2 times,P<0.05).For chlorophyll fluorescence,the parameters F0 and Fm of moss were the highest.Algal and moss had a higher Fv/Fm than lichen.Redundancy Analysis(RDA)showed that the CO_(2)fluxes and chlorophyll fluorescence were positively correlated with the height of grass and NH+4-N content,but negatively correlated with pH.Thus,it is important to consider the contribution of BSCs to the variability of CO_(2)fluxes and chlorophyll fluorescence in different successional stages.

关 键 词：CO_(2)通量 叶绿素荧光 BSCs演替阶段 植被特征 土壤性质 冗余分析 

分 类 号：S812[农业科学—草业科学]