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Jing Zhan - One of the best experts on this subject based on the ideXlab platform.
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development of microbial properties and enzyme activities in copper mine wasteland during natural restoration
Catena, 2014Co-Authors: Jing ZhanAbstract:Abstract A copper mine wasteland consists of a pedogenetic substrate, and regeneration of ecosystems on mine wasteland undergoes typical primary succession. In this study, microbial biomass, basic respiration, microbial diversity and enzyme activities were investigated during the natural successional process in two copper mine Wastelands with different restoration development times. As the plant ecosystem progressed from bare land with cryptogamic crusts to vascular plant communities, organic matter, total nitrogen (N), available phosphorus (P) and water holding capacity increased, whereas pH and toxicity of heavy metals decreased. Along with the natural process of soil development resulting from the amelioration of substrate condition, microbial biomass C and N, and urease and alkaline phosphatase activities in surface layers increased, and the metabolic quotient decreased. Microbial biomass gradually exhibited strong spatial heterogeneity during succession. Microbial biomass and enzyme activities had positive correlations with organic matter and nutrient conditions (N and P), and negative correlations with pH and heavy metals. The concentrations of organic matter, N, P and available Cu significantly influenced microbial biomass and activity. The analysis of 16S rDNA fragments by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) showed no obvious trend in microbial diversity during succession. Phylogenetic analysis of 16S rDNA sequences generated from DGGE gels indicated that bacteria mainly included Proteobacteria ( alpha- , beta- and gamma-Proteobacteria ), Firmicutes ( Bacillus and Clostridia ), Actinobacteria , Nitrospirae , Deinococcus-Thermus and Bacteroidetes . The natural successional series consisted of species adapted to mine Wastelands. Soil microbial biomass and enzyme activities tended to be more sensitive to heavy metals.
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diversity of free living nitrogen fixing microorganisms in the rhizosphere and non rhizosphere of pioneer plants growing on Wastelands of copper mine tailings
Microbiological Research, 2012Co-Authors: Jing Zhan, Qingye SunAbstract:The composition of free-living nitrogen-fixing microbial communities in rhizosphere and non-rhizosphere of pioneer plants growing on Wastelands of copper mine tailings was studied by the presence of nifH genes using Polymerase Chain Reaction-Denatured Gradient Gel Electrophoresis (PCR-DGGE) approach. Eleven rhizosphere tailing samples and nine non-rhizosphere tailing samples from six plant communities were collected from two Wastelands with different discarded periods. The nested PCR method was used to amplify the nifH genes from environmental DNA extracted from tailing samples. Twenty-two of 37 nifH gene sequences retrieved from DGGE gels clustered in Proteobacteria (α-Proteobacteria and β-Proteobacteria) and 15 nifH gene sequences in Cyanobacteria. Most nifH gene fragments sequenced were closely related to uncultured bacteria and cyanobacteria and exhibited less than 90% nucleotide acid identity with bacteria in the database, suggesting that the nifH gene fragments detected in copper mine tailings may represent novel sequences of nitrogen-fixers. Our results indicated that the non-rhizosphere tailings generally presented higher diversity of nitrogen-fixers than rhizosphere tailings and the diversity of free-living nitrogen-fixers in tailing samples was mainly affected by the physico-chemical properties of the Wastelands and plant species, especially the changes of nutrient and heavy metal contents caused by the colonization of plant community.
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diversity of free living nitrogen fixing microorganisms in Wastelands of copper mine tailings during the process of natural ecological restoration
Journal of Environmental Sciences-china, 2011Co-Authors: Jing ZhanAbstract:Biological nitrogen fixing is an important source of nitrogen input in the natural ecological restoration of mine Wastelands. The diversity of nifH genes in tailings samples under different plant communities in Yangshanchong and Tongguanshan Wastelands in Tongling, was analyzed using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) approach. The nitrogen-fixing microorganism community in the upper layer of tailings of Tongguanshan wasteland discarded in 1980 showed higher Shannon-Wiener diversity index than that in Yangshanchong wasteland discarded in 1991. The diversity of nifH genes in Yangshanchong wasteland of copper mine tailings did not display a consistent successional tendency with development of plant communities during the process of natural ecological restoration. Phylogenetic analysis of 25 sequences of nifH gene fragments retrieved from the DGGE gels indicated that there were mainly two taxa of free-living nitrogen-fixing microorganisms, Proteobacteria and Cyanobacteria living in the Wastelands investigated, most of which were unique and uncultured. Canonical correspondence analysis (CCA) based on the relationship between band patterns of DGGE profile and physico-chemical properties of tailings samples showed that the diversity of nifH genes in different tailing samples was mainly affected by loss of ignition, water content, pH and available Zn contents of Wastelands. The dominant plant species and development period of plant communities by ameliorating pH, reducing the toxicity of heavy metals, increasing organic matter and water content affected the diversity and structure of the free-living nitrogen-fixing microorganisms in Wastelands of copper mine tailings.
Changyong Huang - One of the best experts on this subject based on the ideXlab platform.
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effect of lime application on microbial community in acidic tea orchard soils in comparison with those in wasteland and forest soils
Journal of Environmental Sciences-china, 2010Co-Authors: Xiangdong Huang, Changyong HuangAbstract:Lime application is a conventional technology to control acidification in tea orchard soils. We investigated the effect of lime application on soil microbial community diversity in the soils of three tea orchards, wasteland and forest. The BIOLOG data showed that both the average well color development of all carbon sources and the functional diversity index increased with the liming rate in the tea orchards and the forest, but decreased in the wasteland. The phospholipid fatty acid (PLFA) analysis showed that the structural diversity index of soil microbial community increased with the liming rate in all the tea orchards, the wasteland and the forest. Lime application also increased the soil-bacterial PLFA content in all the soils. Soil fungal and actinomycete PLFAs in the tea orchards showed an increasing trend from 0 to 3.2 g CaCO3/kg application and then a decreasing trend from 3.2 to 6.4 g CaCO3/kg application. The principal component analysis of BIOLOG and PLFA data suggested that lime application had a significant effect on soil microbial community structure, and land use had a greater effect on soil microbial community structure compared to lime application.
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nitrification potentials of chinese tea orchard soils and their adjacent wasteland and forest soils
Journal of Environmental Sciences-china, 2009Co-Authors: Yangmei Gao, Huaiying Yao, Dong Xue, Changyong HuangAbstract:To investigate the nitrifying activities of different soil types, soil samples collected from 8-, 50- and 90-year old tea orchards, the adjacent wasteland, and 90-year old forest were measured for their nitrification potentials using the conventional soil incubation and the liquid incubation method. Among different soil types, the nitrification potential of soil in tea orchards was higher than that of wasteland and forest soils. The slurry shaken liquid incubation method was confirmed to be more accurate and have reliable results than the soil incubation. Interestingly, experimental result revealed that the generally applied pH value of 7.2 for the liquid media was not the optimal pH for these acid soils with a strong buffer capacity. This suggested that tea orchard soils may have nitrifiers requiring pH-neutral condition for the best activity. Our data also showed that treatment with the commonly used nitrogen fertilizer urea significantly improved nitrification potential of the soils; such enhancement effect was stronger on all of three tea orchard soils than on wasteland and forest soils, and also stronger on the younger (8- and 50-year old) tea orchard soils than on the older one (90-year old).
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microbial biomass n mineralization and nitrification enzyme activities and microbial community diversity in tea orchard soils
Plant and Soil, 2006Co-Authors: Dong Xue, Huaiying Yao, Changyong HuangAbstract:Understanding the chronological changes in soil microbial and biochemical properties of tea orchard ecosystems after wasteland has been reclaimed is important from ecological, environmental, and management perspectives. In this study, we determined microbial biomass, net N mineralization, and nitrification, enzyme (invertase, urease, proteinase, and acid phosphatase) activities, microbial community diversity assessed by denaturing gradient gel electrophoresis (DGGE) of 16S rDNA polymerase chain reaction (PCR) products, and related ecological factors in three tea orchard systems (8-, 50-, and 90-year-old tea orchards), adjacent wasteland and 90-year-old forest. Soil microbial biomass C (Cmic) and activity, i.e., soil basal respiration (Rmic), microbial biomass C as a percent of soil organic C (Cmic/Corg), N mineralization, invertase, urease, proteinase, and acid phosphatase, significantly increased after wasteland was reclaimed; however, with the succeeding development of tea orchard ecosystems, a decreasing trend from the 50- to 90-year-old tea orchard became apparent. Soil net nitrification showed an increasing trend from the 8- to 50-year-old tea orchard and then a decreasing trend from the 50- to 90-year-old tea orchard, and was significantly higher in the tea orchards compared to the wasteland and forest. Urea application significantly stimulated soil net nitrification, indicating nitrogen fertilizer application may be an important factor leading to high-nitrification rates in tea orchard soils. The Shannon’s diversity index (H) and richness (S) based on DGGE profiles of 16S rRNA genes were obviously lower in all three tea orchards than those in the wasteland; nevertheless, they were significantly higher in all three tea orchards than those in the forest. As for the three tea orchard soils, comparatively higher community diversity was found in the 50-year-old tea orchard.
Sha Gao - One of the best experts on this subject based on the ideXlab platform.
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combining stable carbon isotope analysis and petroleum fingerprinting to evaluate petroleum contamination in the yanchang oilfield located on loess plateau in china
Environmental Science and Pollution Research, 2018Co-Authors: Yiping Wang, Jidong Liang, Jinxing Wang, Sha GaoAbstract:This study evaluated petroleum contamination in the Yanchang (Shaanxi Yanchang Petroleum (Group) Co., Ltd.) oilfield, located in the loess plateau region of northern Shaanxi, China. Surface soil and sediment samples were collected from the wasteland, farmland, and riverbed in this area to assess the following parameters: total petroleum hydrocarbon (TPH), n-alkanes, polycyclic aromatic hydrocarbons (PAHs), and carbon isotope ratios (δ13C). The results showed that TPH and PAH levels in the study area were 907-3447 mg/kg and 103.59-563.50 μg/kg, respectively, significantly higher than the control samples (TPH 224 mg/kg, PAHs below method quantification limit, MQL). Tests using δ13C to detect modified TPH (2238.66 to 6639.42 mg/kg) in the Wastelands adjacent to the oil wells revealed more significant contamination than tests using extraction gravimetric analysis. In addition, "chemical fingerprint" indicators, such as low to high molecular weight (LMW/HMW) hydrocarbons, carbon preference index (CPI), and pristine/phytane (Pr/Ph), further confirmed the presence of heavy petroleum contamination and weathering. This has resulted in a nutrient imbalance and unsuitable pH and moisture conditions for microbial metabolic activities. This study evaluates petroleum contamination, which can inform contamination remediation on a case by case basis.
Dong Xue - One of the best experts on this subject based on the ideXlab platform.
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nitrification potentials of chinese tea orchard soils and their adjacent wasteland and forest soils
Journal of Environmental Sciences-china, 2009Co-Authors: Yangmei Gao, Huaiying Yao, Dong Xue, Changyong HuangAbstract:To investigate the nitrifying activities of different soil types, soil samples collected from 8-, 50- and 90-year old tea orchards, the adjacent wasteland, and 90-year old forest were measured for their nitrification potentials using the conventional soil incubation and the liquid incubation method. Among different soil types, the nitrification potential of soil in tea orchards was higher than that of wasteland and forest soils. The slurry shaken liquid incubation method was confirmed to be more accurate and have reliable results than the soil incubation. Interestingly, experimental result revealed that the generally applied pH value of 7.2 for the liquid media was not the optimal pH for these acid soils with a strong buffer capacity. This suggested that tea orchard soils may have nitrifiers requiring pH-neutral condition for the best activity. Our data also showed that treatment with the commonly used nitrogen fertilizer urea significantly improved nitrification potential of the soils; such enhancement effect was stronger on all of three tea orchard soils than on wasteland and forest soils, and also stronger on the younger (8- and 50-year old) tea orchard soils than on the older one (90-year old).
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microbial biomass n mineralization and nitrification enzyme activities and microbial community diversity in tea orchard soils
Plant and Soil, 2006Co-Authors: Dong Xue, Huaiying Yao, Changyong HuangAbstract:Understanding the chronological changes in soil microbial and biochemical properties of tea orchard ecosystems after wasteland has been reclaimed is important from ecological, environmental, and management perspectives. In this study, we determined microbial biomass, net N mineralization, and nitrification, enzyme (invertase, urease, proteinase, and acid phosphatase) activities, microbial community diversity assessed by denaturing gradient gel electrophoresis (DGGE) of 16S rDNA polymerase chain reaction (PCR) products, and related ecological factors in three tea orchard systems (8-, 50-, and 90-year-old tea orchards), adjacent wasteland and 90-year-old forest. Soil microbial biomass C (Cmic) and activity, i.e., soil basal respiration (Rmic), microbial biomass C as a percent of soil organic C (Cmic/Corg), N mineralization, invertase, urease, proteinase, and acid phosphatase, significantly increased after wasteland was reclaimed; however, with the succeeding development of tea orchard ecosystems, a decreasing trend from the 50- to 90-year-old tea orchard became apparent. Soil net nitrification showed an increasing trend from the 8- to 50-year-old tea orchard and then a decreasing trend from the 50- to 90-year-old tea orchard, and was significantly higher in the tea orchards compared to the wasteland and forest. Urea application significantly stimulated soil net nitrification, indicating nitrogen fertilizer application may be an important factor leading to high-nitrification rates in tea orchard soils. The Shannon’s diversity index (H) and richness (S) based on DGGE profiles of 16S rRNA genes were obviously lower in all three tea orchards than those in the wasteland; nevertheless, they were significantly higher in all three tea orchards than those in the forest. As for the three tea orchard soils, comparatively higher community diversity was found in the 50-year-old tea orchard.
Qingye Sun - One of the best experts on this subject based on the ideXlab platform.
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diversity of free living nitrogen fixing microorganisms in the rhizosphere and non rhizosphere of pioneer plants growing on Wastelands of copper mine tailings
Microbiological Research, 2012Co-Authors: Jing Zhan, Qingye SunAbstract:The composition of free-living nitrogen-fixing microbial communities in rhizosphere and non-rhizosphere of pioneer plants growing on Wastelands of copper mine tailings was studied by the presence of nifH genes using Polymerase Chain Reaction-Denatured Gradient Gel Electrophoresis (PCR-DGGE) approach. Eleven rhizosphere tailing samples and nine non-rhizosphere tailing samples from six plant communities were collected from two Wastelands with different discarded periods. The nested PCR method was used to amplify the nifH genes from environmental DNA extracted from tailing samples. Twenty-two of 37 nifH gene sequences retrieved from DGGE gels clustered in Proteobacteria (α-Proteobacteria and β-Proteobacteria) and 15 nifH gene sequences in Cyanobacteria. Most nifH gene fragments sequenced were closely related to uncultured bacteria and cyanobacteria and exhibited less than 90% nucleotide acid identity with bacteria in the database, suggesting that the nifH gene fragments detected in copper mine tailings may represent novel sequences of nitrogen-fixers. Our results indicated that the non-rhizosphere tailings generally presented higher diversity of nitrogen-fixers than rhizosphere tailings and the diversity of free-living nitrogen-fixers in tailing samples was mainly affected by the physico-chemical properties of the Wastelands and plant species, especially the changes of nutrient and heavy metal contents caused by the colonization of plant community.
