宁夏荒漠草原典型灌丛根际土壤酶活性及微生物代谢多样性  

Enzyme activity and microbial metabolic diversity in typical shrub rhizosphere soil in Ningxia desert steppe

作　　者：姚佳妮 刘爽 张钧杰 胡明珠 代金霞 Jia-ni YAO;Shuang LIU;Jun-jie ZHANG;Ming-zhu HU;Jin-xia DAI(College of Life Sciences,Ningxia University,Yinchuan 750021,China)

机构地区：[1]宁夏大学生命科学学院,宁夏银川750021

出　　处：《草业学报》2024年第9期1-14,共14页Acta Prataculturae Sinica

基　　金：国家自然科学基金项目(32160023,31760027);宁夏自然科学基金项目(2023AAC03062)资助。

摘　　要：开展荒漠灌丛根际土壤酶活性和微生物代谢多样性研究,对于荒漠土壤的生态修复具有重要意义。运用可见分光光度法和Biolog微平板法,对宁夏白芨滩荒漠草原内柠条、沙冬青、毛刺和猫头刺4种典型的豆科灌丛不同发育期根际土壤酶活性及微生物代谢功能多样性进行了研究。结果表明:不同灌丛各发育期根际土壤的酶活性存在显著差异。从灌丛种类来看,沙冬青根际土壤脲酶活性均显著高于其他3种灌丛,毛刺根际土壤碱性磷酸酶活性均显著低于其他灌丛。从发育期来看,营养期沙冬青根际土壤脲酶和碱性磷酸酶活性显著高于其他时期,柠条根际土壤脲酶和蔗糖酶活性显著低于其他时期;盛花期柠条根际土壤脲酶和碱性磷酸酶活性、沙冬青根际土壤蔗糖酶活性、猫头刺根际土壤脲酶和脱氢酶活性显著高于其他时期;果实期沙冬青根际土壤脲酶和碱性磷酸酶活性最高,柠条根际土壤蔗糖酶和脱氢酶活性最高;毛刺的盛花期和果实期根际土壤中酶活性普遍较低。不同灌丛各发育期根际土壤微生物群落代谢多样性大多存在显著差异。4种灌丛根际土壤平均颜色变化率(average well color development,AWCD)均随培养时间的延长而逐渐增加,碳源利用类型主要为碳水化合物、氨基酸和羧酸。柠条营养期根际土壤中微生物分布较均匀,代谢活性强,生长旺盛。主成分分析(principal component analysis,PCA)显示,营养期沙冬青、毛刺和猫头刺根际土壤微生物的碳源利用模式相似;盛花期柠条、沙冬青和猫头刺根际土壤微生物的碳源利用模式相似;果实期柠条和沙冬青、毛刺和猫头刺根际土壤微生物的碳源利用模式相似。随着发育期的变化,土壤微生物碳源利用模式发生不同程度的变化。冗余分析(redundancy analysis,RDA)显示,酶活性和微生物代谢功能与土壤理化性质关系密切。脲酶与铵态氮(NH_This research investigated the enzyme activity and microbial metabolic diversity of desert shrub rhizosphere soil for ecological restoration of desert soil.Four selected legume shrub species(Caragana spp.,Ammopiptanthus mongolicus,Caragana tibetica and Oxytropis aciphylla)within the Baijitan desert steppe in Ningxia were investigated using visible wavelength spectrophotometry and Biolog microplates,to determine if rhizosphere soil enzyme activity differed in different seasonal development periods(early season‘nutritional’,flowering,and fruiting periods)and to determine the functional diversity of microbial metabolism.Significant differences in the enzyme activity of rhizosphere soil in the different seasonal phases of shrub growth were detected.In terms of different development periods,the rhizosphere soil urease activity of A.mongolicus was significantly higher than the other three shrubs,and the rhizosphere soil alkaline phosphatase activity of C.tibetica was significantly lower than the other shrubs.For the different development periods,during the nutritional period,rhizosphere soil urease and alkaline phosphatase activity of A.mongolicus were significantly higher than those of other periods,and rhizosphere soil urease and sucrase activity of the unidentified Caragana spp.were significantly lower than those of other periods.During the flowering period,rhizosphere soil urease and alkaline phosphatase activities ofthe Caragana spp.,soil sucrase activity of A.mongolicus,and soil urease and dehydrogenase activities of O.aciphylla were significantly higher than at other periods.In the fruiting period,rhizosphere soil urease and alkaline phosphatase activities were highest in A.mongolicus and soil sucrase and dehydrogenase activities were highest in Caragana spp.Enzyme activities were generally low in the rhizosphere soils of C.tibetica during the flowering and fruiting periods.There were significant differences in the metabolic diversity of rhizosphere soil microbial communities in the different seasonal period

关 键 词：豆科灌丛 土壤酶活性 Biolog法 碳源利用 代谢多样性 

分 类 号：S812.2[农业科学—草业科学]