【摘要】 以鄱阳湖南矶山湿地为研究区域,研究了三种典型植被南荻、芦苇、苔草土壤中的砷和硒形态的分布特征以及与土壤酶活性、微生物群落结构的关系。结果表明:三种植被土壤砷含量平均值为16.21±3.77(mg·kg^-1),大小顺序为:南荻>芦苇>苔草;土壤硒含量平均值为0.33±0.02(mg·kg^-1),大小顺序为:苔草>芦苇>南荻。土壤砷形态含量大小顺序为:残渣态砷>铁型砷>钙型砷>铝型砷>交换态砷,残渣态砷和残渣态硒含量均分别约占总砷和总硒含量的50%。南荻、苔草和芦苇的可交换态硒的百分含量分别为:7.36±0.04%,9.27±0.06%和7.72±0.05%。芦苇、苔草和南荻的总PLFA含量分别为132.29±3.72、93.26±2.39和122.97±3.15(nmol·g^-1),呈现芦苇>南荻>苔草趋势。铝型砷含量与土壤脲酶显著正相关;残渣态砷与放线菌显著正相关,与蔗糖酶和脱氢酶显著负相关;水溶态硒与革兰氏阳性菌呈显著正相关,与真菌、脲酶、过氧化氢酶呈显著负相关。交换态硒和残渣态硒都与蔗糖酶呈正相关,与放线菌呈负相关。实验结果表明,土壤中的砷和硒的形态与土壤微生物活性和群落结构密切相关。更多还原

【Abstract】 Taking Nanjishan wetland of Poyang Lake as the research area,the distribution characteristics of arsenic and selenium in soils of three typical vegetation soils such as Triarrhena lutarioriparia,Phragmites australic,Carex,and their relationship with soil enzyme activity and microbial community structure were studied.The results show that the average arsenic content of the three vegetation soils was 16.21±3.77 mg·kg^-1,and the order is:Triarrhena lutarioriparia>Phragmites australis>Carex;The average selenium content in soil is 0.33±0.02 mg·kg^-1,and the order is:Carex>Phragmites australis>Triarrhena lutarioriparia.The order of arsenic content in soil was as follows:residual arsenic>iron arsenic>calcium arsenic>aluminum arsenic>exchange arsenic.Residual arsenic and residual selenium content account for about 50% total arsenic and total selenium,respectively.The percentages of exchangeable selenium in Triarrhena lutarioriparia,Carex and Phragmites australis were:7.36±0.04%,9.27±0.06% and 7.72±0.05%,respectively.The total PLFA contents of Phragmites australis,Carex and Triarrhena lutarioriparia were 132.29±3.72,93.26±2.39 and 122.97±3.15 nmmol·g^-1,respectively,showing the trend of Phragmites australis>Triarrhena lutarioriparia>Carex.Aluminum arsenic content is significantly positively correlated with soil urease;Residual arsenic was significantly positively correlated with actinomycetes and significantly negatively correlated with sucrase and dehydrogenase;Water-soluble selenium was significantly positively correlated with Gram-positive bacteria and negatively correlated with fungi,urease and catalase.Both exchangeable selenium and residual selenium were positively correlated with invertase and negatively correlated with actinomycetes.The results show that the forms of arsensic and selenium in soil were closely related to the microbial activity and community structure.更多还原