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The Aureobasidium pullulans F4 was isolated from the rhizosphere of Hippochaete ramosissimum in Tongguanshan mine wasteland in Tongling City, Anhui Province. Liquid culture was conducted with four kinds of phosphorus sources, calcium phosphate, aluminum phosphate, ferric phosphate and rock phosphate to determine the pH, dissolved phosphorus, phosphorus in the bacteria and organic acid in the solution. The results showed that the phosphate solubilization by A. pullulans F4 varied with phosphorus sources, which decreased in order of aluminum phosphate > ferric phosphate,calcium phosphate > rock phosphate. The amounts of dissolved phosphorus in the different treatments were all higher than 200 mg·L-1. The pH of the medium dropped immediately in 48 h, and the aluminum phosphate and ferric phosphate treatments showed a greater decrease in pH than the calcium phosphate and rock phosphate treatments. The organic acid synthesized by A. pullulans F4 included oxalic acid, citric acid and tartaric acid, and oxalic acid, among which oxalic acid was the dominated component. The phosphate dissolving capacity of A. pullulans F4 showed no significant correlation with organic acid, but significantly correlated with the pH. The available phosphorus was significantly improved with the combined application of A. pullulans F4 and glucose, suggesting A. pullulans F4 was a potent candidate for remediation of copper mine wastelands. [ABSTRACT FROM AUTHOR]

Biological soil crusts play an important role in increasing the accumulation of organic matter and nitrogen in revegetated mining wastelands. The diversity of nitrogen-fixing microorganisms in three types of biological soil crusts (algal crust, moss crust and algal moss crust) from two wastelands of copper mine tailings were investigated by polymerase chain reaction denaturing gradient gel electrophoresis, based on the nifH gene of diazotrophs, to investigate: The diversity of nifH gene in the crusts of mine wastelands, and whether and how the nifH gene diversity in the crusts could be affected by the development of plant communities. The algal crust on the barren area displayed the highest nifH gene diversity, followed by the algal moss crusts within vascular plant communities, and the moss crust displayed the lowest nifH gene diversity. The diversity of diazotrophs in algal moss crust within vascular plant communities decreased with the increase of height and cover of vascular plant communities. No significant relationship was found between wasteland properties (pH, water content, contents of organic matter, nitrogen and phosphorus and heavy metal concentration) and nifH gene diversity in the crusts. Sequencing and phylogenetic analysis indicated that most nitrogen-fixing taxa in the crusts of mine wastelands belonged to Cyanobacteria, especially nonheterocystous filamentous Cyanobacteria. [ABSTRACT FROM AUTHOR]

Tongling is one of the main non-ferrous metal mining areas in China, and the biodiversity in the river ecosystem of this area is seriously affected by heavy metals as a result of mining activities. In the winter in 2010, an investigation was conducted on the community structure of phytoplankton and its relationships with environmental factors in the main sections of the rivers in Tongling. A total of 203 phytoplankton species were identified, belonging to 96 genera and 8 phyla. The community structure of the phytoplankton differed obviously in different river sections, but the communities were all dominated by Bacillariophyta, Chlorophyta and Cyanophyta. The phytoplankton abundance ranged from 9. 1×103 to 6. 5×107 cells·L-1, and the quantity of the phytoplankton in the river sections directly carried with mining waste water was significantly low. The Shannon index of the phytoplankton community at different sampling sites ranged from 0 to 3. 45, with a significant discrepancy in different river sections. There existed significant correlations between the density and group number of phytoplankton and the CODCr and cadmium, copper and zinc concentrations in the rivers, and the concentrations of river total nitrogen, NH4 +-N, NO3 --N, and copper, CODCr and pH were the main environmental variables affecting the phytoplankton's community structure and its spatial distribution. Although the nutritional status of the river waters had greater effects on the community structure of phytoplankton, the effects of the heavy metals there from mining enterprises could not be neglected. [ABSTRACT FROM AUTHOR]

Various phosphatesolubilizing bacterial strains were isolated from the Hippochaete ramo sissimum rhizosphere in Tongguanshan copper tailings in Tongling of Anhui Province, East China. After many times of screening and purification, a strain B25 with stronger phosphatesolubilizing ca pability was obtained, which belonged to Bacillus genus, as identified by transmission electron microscope and DNA molecular approaches. A culture experiment was conducted to study the phosphate-solubilizing capability of the B25 within 168 h and the variations of the medium pH and B25 growth as well as the phosphate-solubilizing capability of B25 under different culture conditions. A weak correlation was observed between the phosphate-solubilizing capability of B25 and the medium pH. The B25 displayed a better phosphate-solubilizing capability when the carbon source was glucose, medium initial pH was 7. 0, and culture temperature was 30 °C. [ABSTRACT FROM AUTHOR]

Bio-crust is the initial stage of natural primary succession in copper mine tailings. With the Yangshanchong and Tongguanshan copper mine tailings in Tongling City of Anhui Province as test objects, this paper studied the soil microbial biomass C and N and the activities of dehydrogenase, catalase, alkaline phosphatase, and urease under different types of bio-crust. The bio-crusts improved the soil microbial biomass and enzyme activities in the upper layer of the tailings markedly. Algal crust had the best effect in improving soil microbial biomass C and N, followed by moss-algal crust, and moss crust. Soil microflora also varied with the type of bio-crust. No significant difference was observed in the soil enzyme activities under the three types of bio-crust. Soil alkaline phosphatase activity was significantly positively correlated with soil microbial biomass and dehydrogenase and urease activities, but negatively correlated with soil pH. In addition, moss rhizoid could markedly enhance the soil microbial biomass and enzyme activities in moss crust rhizoid. [ABSTRACT FROM AUTHOR]

Both the photosynthetic light curves and CO2 curves of Juglans regia L. and Ziziphus jujuba Mill. var. spinosa in three seasons were measured using a LI-6400 portable photosynthesis system. The maximal net photosynthetic rate (Amax), apparent quantum efficiency(φ), maximal carboxylation rate (Vcmax) and water use efficiency (WUE) of the two species were calculated based on the curves. The results showed that Amax of J. regia reached its maximum at the late-season, while the highest values of Amax of Z. jujuba occurred at the mid-season. The Amax of J. regia was more affected by relative humidity (RH) of the atmosphere, while that of Z. jujuba was more affected by the air temperature. Light saturation point (LSP) and Light compensation point (LCP) of J. regia had a higher correlation with RH of the atmosphere, those of Z. jujuba, however, had a higher correlation with air temperature. Vcmax of both J. regia and Z. jujuba had negative correlation with RH of the atmosphere. WUE of J. regia would decrease with the rise of the air temperature while that of Z. jujuba increased. Thus it could be seen that RH, temperature and soil moisture had main effect on photosynthesis and WUE of J. regia and Z. jujuba. Incorporating data on the physiological differences among tree species into forest carbon models will greatly improve our ability to predict alterations to the forest carbon budgets under various environmental scenarios such as global climate change, or with differing species composition. [ABSTRACT FROM AUTHOR]

Hydrochar, as a product of the hydrothermal carbonization of biomass, has good application prospects for the NH 3 volatilization reduction in rice fields due to its rich pore structure and functional surface. In this study, hydrochar was applied as a soil conditioner to paddy soil. A soil column experiment was conducted to investigate the effect of hydrochar on NH 3 volatilization throughout the growth period of rice. The experiment was conducted with three treatments:CKU (control without hydrochar); SHC (sawdust hydrochar); and W-SHC (water-washed sawdust hydrochar). The application rate of SHC and W-SHC was 0.5% ( w/w ). The study investigated the effects of different hydrochars on the pH and concentrations of NH 4 + -N in floodwater, the flux and accumulation of NH 3 volatilization, and the yield-scale cumulative emission of NH 3 volatilization. Results show that the SHC treatment significantly reduces cumulative emissions of NH 3 volatilization and the yield-scale cumulative emissions of NH 3 volatilization ( P <0.05), which were 32.42% and 47.61% lower than CKU, respectively. The effect of W-SHC on ammonia volatilization reduction was slightly weaker, as the cumulative emissions of NH 3 volatilization and the yield-scale cumulative emissions of NH 3 volatilization decreased by 10.14% and 27.71%, respectively, compared with CKU. The NH 3 volatilization reduction was possibly related to the disturbance of pH and the decrease in NH 4 + -N concentrations in the floodwater because of the application of hydrochar. Compared with CKU, both SHC and W-SHC treatments reduced the pH and NH 4 + -N concentration in the floodwater. The impacts were more obvious in the rice base fertilizer period (BF) and the first supplemental fertilizer period (SF1) than in the second supplemental fertilizer period (SF2). The soil urease activity was significantly inhibited by hydrochar ( P <0.05), and the abundance of soil ammonia-oxidizing gene (AOA, AOB) also significantly increased after application of SHC ( P <0.05). This resulted in the enhanced efficiency of ammonia-oxidizing, which had an effect on the reduction of the NH 4 + -N concentrations in the floodwater. This study provides theoretical and experimental data support for the application of hydrochar in agro-environments with regard to ammonia volatilization reduction in paddy fields.

Rivers in mining areas were influenced by contaminants such as nitrogen, phosphorus and organic matter due to domestic and agricultural wastewater discharge in addition to pollutants caused by mining activities. In this study, surface sediment samples of rivers in Tongling city were collected to address the effect of season and pollution type on the abundance of nitrifiers and denitrifiers using quantitative polymerase chain reaction (QPCR) technique targeting at the ammonia monooxygenase (amoA) and nitrite reductase (nir) genes. The results showed that the average ahundance of ammonia oxidizing archaea (AGA) (ranging from 1.74 x 10⁵ to 1.45 x 10⁸ copies · g⁻¹) was 4.39 times that of ammonia oxidizing hacteria (AGH) (ranging from 1.39 x 10⁵ to 3.39 x 10⁷ copies · g⁻¹); and the average abundance of nirK gene (ranging from 4.45 x 10⁶ to 1.51 x 10⁸ copies · g) was almost a thirtieth part of nirS gene (ranging from 1.69 x 10⁷ to 8.55 x 10⁹ copies · g⁻¹). The abundance of AOA was higher in spring and autumn, and lower in summer and winter. And sediment AOB abundance was higher in spring and winter than in summer and autumn. Meanwhile, the abundance of nir genes was in the order of spring (nirS )/autumn (nirK) > summer > winter > autumn (nirS )/spring (nirK). Moreover, the abundance of bacterial and archaeal arnoA and nirS genes in sediments influenced by mine pollution was generally higher than that in sediments influenced by agricultural non-point pollution, whereas the abundance of nirK gene showed an opposite trend.

The Aureobasidium pullulans F4 was isolated from the rhizosphere of Hippochaete ramosissimum in Tongguanshan mine wasteland in Tongling City, Anhui Province. Liquid culture was conducted with four kinds of phosphorus sources, calcium phosphate, aluminum phosphate, ferric phosphate and rock phosphate to determine the pH, dissolved phosphorus, phosphorus in the bacteria and organic acid in the solution. The results showed that the phosphate solubilization by A. pullulans F4 varied with phosphorus sources, which decreased in order of aluminum phosphate > ferric phosphate, calcium phosphate > rock phosphate. The amounts of dissolved phosphorus in the different treatments were all higher than 200 mg x L(-1). The pH of the medium dropped immediately in 48 h, and the aluminum phosphate and ferric phosphate treatments showed a greater decrease in pH than the calcium phosphate and rock phosphate treatments. The organic acid synthesized by A. pullulans F4 included oxalic acid, citric acid and tartaric acid, and oxalic acid, among which oxalic acid was the dominated component. The phosphate dissolving capacity of A. pullulans F4 showed no significant correlation with organic acid, but significantly correlated with the pH. The available phosphorus was significantly improved with the combined application of A. pullulans F4 and glucose, suggesting A. pullulans F4 was a potent candidate for remediation of copper mine wastelands.

Biological soil crusts play an important role in increasing the accumulation of organic matter and nitrogen in re-vegetated mining wastelands. The diversity of nitrogen-fixing microorganisms in three types of biological soil crusts (algal crust, moss crust and algal-moss crust) from two wastelands of copper mine tailings were investigated by polymerase chain reaction-denaturing gradient gel electrophoresis, based on the nifH gene of diazotrophs, to investigate: The diversity of nifH gene in the crusts of mine wastelands, and whether and how the nifH gene diversity in the crusts could be affected by the development of plant communities. The algal crust on the barren area displayed the highest nifH gene diversity, followed by the algal-moss crusts within vascular plant communities, and the moss crust displayed the lowest nifH gene diversity. The diversity of diazotrophs in algal-moss crust within vascular plant communities decreased with the increase of height and cover of vascular plant communities. No significant relationship was found between wasteland properties (pH, water content, contents of organic matter, nitrogen and phosphorus and heavy metal concentration) and nifH gene diversity in the crusts. Sequencing and phylogenetic analysis indicated that most nitrogen-fixing taxa in the crusts of mine wastelands belonged to Cyanobacteria, especially nonheterocystous filamentous Cyanobacteria.

Tongling is one of the main non-ferrous metal mining areas in China, and the biodiversity in the river ecosystem of this area is seriously affected by heavy metals as a result of mining activities. In the winter in 2010, an investigation was conducted on the community structure of phytoplankton and its relationships with environmental factors in the main sections of the rivers in Tongling. A total of 203 phytoplankton species were identified, belonging to 96 genera and 8 phyla. The community structure of the phytoplankton differed obviously in different river sections, but the communities were all dominated by Bacillariophyta, Chlorophyta and Cyanophyta. The phytoplankton abundance ranged from 9.1 x 10(3) to 6.5 x 10(7) cells x L(-1), and the quantity of the phytoplankton in the river sections directly carried with mining waste water was significantly low. The Shannon index of the phytoplankton community at different sampling sites ranged from 0 to 3.45, with a significant discrepancy in different river sections. There existed significant correlations between the density and group number of phytoplankton and the COD(Cr) and cadmium, copper and zinc concentrations in the rivers, and the concentrations of river total nitrogen, NH4(+)-N, NO3(-)-N, and copper, COD(Cr) and pH were the main environmental variables affecting the phytoplankton' s community structure and its spatial distribution. Although the nutritional status of the river waters had greater effects on the community structure of phytoplankton, the effects of the heavy metals there from mining enterprises could not be neglected.

Various phosphate-solubilizing bacterial strains were isolated from the Hippochaete ramosissimum rhizosphere in Tongguanshan copper tailings in Tongling of Anhui Province, East China. After many times of screening and purification, a strain B25 with stronger phosphate-solubilizing capability was obtained, which belonged to Bacillus genus, as identified by transmission electron microscope and DNA molecular approaches. A culture experiment was conducted to study the phosphate-solubilizing capability of the B25 within 168 h and the variations of the medium pH and B25 growth as well as the phosphate-solubilizing capability of B25 under different culture conditions. A weak correlation was observed between the phosphate-solubilizing capability of B25 and the medium pH. The B25 displayed a better phosphate-solubilizing capability when the carbon source was glucose, medium initial pH was 7.0, and culture temperature was 30 degrees C.

Total phosphorus (TP), inorganic-phosphorus(IP), organic-phosphorus (OP), Fe/Al-bound phosphorus (NaOH-P) and Ca-bound phosphorus (HCl-P) in surface sediments of Chaohu Lake were measured, using the standard measurement and test (SMT) procedure of phosphorus forms in freshwater sediments. ArcGIS 9.2 and goestatistics software GS + 5. 3 were applied to process the spatial data and interpolation. Results showed that no significant seasonal variation of TN, TP and organic matter contents in sediments were presented, and the western lake had higher contents of TN, TP and organic matter than those in eastern lake; the C/N ratios varied from 21.35 to 28.19, with average value of 24.94, which demonstrated the dominance of non-point source pollution. The TP contents in surface sediments ranged from 528.90 to 1 385.71 mg x kg(-1), and the main form of TP in sediments was IP(accounted for 55.78% -79.86% of TP). The OP in sediments ranged from 169.05 mg x kg(-1) to 841.24 mg x kg(-1), with eastern lake and western lake were 376.02 mg x kg(-1) and 406.53 mg x kg(-1), respectively (accounted for 47.49% and 36.28% of TP); the NaOH-P contents in sediments ranged from 33.77 mg x kg(-1) to 411.37 mg x kg(-1), with eastern lake and western lake of 376.02 mg x kg(-1) and 406.53 mg x kg(-1), respectively (accounted for 21.73% and 33.12% of the IP); the HCl-P contents ranged from 194.95 mg x kg(-1) to 477.45 mg x kg(-1), with eastern lake and western lake 321.71 mg x kg(-1). and 338.08 mg x kg(-1), respectively (accounted for 64.50% and 40.53% of the IP), which was the main species of IP. The OP contents was high in spring and winter compared with summer and autumn, while the contents of HCl-P and NaOH-P in summer and autumn were higher than those in spring and winter.

There are a lot of ponds around Chaohu Lake. According to location and runoff supply of ponds, the ponds are divided into three types: ponds inner vellage (PIV), ponds adjacent vellage (PAV) and ponds outer vellage (POV). The samples of water and sediment were collected from 136 ponds around Chaohu Lake and the contents of nitrogen, phosphorus and organic matter in water and sediments were analyzed in this study. The results showed that mean contents of total nitrogen (TN), NH4+ -N, NO3- -N, NO2- -N, total phosphorus (TP), soluble PO4(3-) -P and COD were 2.53, 0.65, 0.18, 0.02, 0.97, 0.38 and 51.58 mg x L(-1) in pond water, respectively; and mean contents of TN, NH4+ -N, NO3- -N, NO2- -N, TP, inorganic phosphorus (IP), organic phosphorus (OP) and loss of ignition (LOI) in pond sediment were 1575.36, 35.73, 13.30, 2.88, 933.19, 490.14, 414.75 mg x kg(-1) and 5.44%, respectively. The ponds of more than 90% presented eutrophication in the contents of total nitrogen and phosphorus in water. The contents of TN and NH4+ -N in water and sediment of PIV were significantly higher than that of POV. And the contents of inorganic nitrogen in pond water and sediment displayed a following order: NH4+ -N > NO3- -N > NO2- -N. Data analysis indicated that there was a significantly positive correlation between organic matter and total nitrogen and phosphorus in water and sediment. The nitrogen, phosphorus and organic matter in ponds mainly sourced farmlands and village land surface. The contents of nitrogen, phosphorus and organic matter in ponds were affected by location and runoff supply of ponds. By retaining nitrogen, phosphorus and organic matter in runoff, the ponds can effectively decrease nutrient content into Chaohu Lake.

Bio-crust is the initial stage of natural primary succession in copper mine tailings. With the Yangshanchong and Tongguanshan copper mine tailings in Tongling City of Anhui Province as test objects, this paper studied the soil microbial biomass C and N and the activities of dehydrogenase, catalase, alkaline phosphatase, and urease under different types of bio-crust. The bio-crusts improved the soil microbial biomass and enzyme activities in the upper layer of the tailings markedly. Algal crust had the best effect in improving soil microbial biomass C and N, followed by moss-algal crust, and moss crust. Soil microflora also varied with the type of bio-crust. No'significant difference was observed in the soil enzyme activities under the three types of bio-crust. Soil alkaline phosphatase activity was significantly positively correlated with soil microbial biomass and dehydrogenase and urease activities, but negatively correlated with soil pH. In addition, moss rhizoid could markedly enhance the soil microbial biomass and enzyme activities in moss crust rhizoid.

Solution culture experiment was carried out to investigate the effects on the removal efficiencies of N and P by perennial ryegrass (Lolium perenne L.) under the Cu stress and the ecological response of ryegrass to various dosages of Cu2+. The results indicated that the removal efficiencies of N and P decreased under all the intimidating conditions compared with the control tanks, which followed the second-rate equation. The removal efficiencies of N and P and the plant growth at low Cu2+ concentrations (< or = 0.2 mg/L) were higher than those at high Cu2+ concentration (> or = 0.5 mg/L), and the biomass (dry weight) was increased at low Cu2+ concentrations (< or = 0.2 mg/L) relative to control solution. In addition, the plant was able to remove Cu2+ in the eutrophic water simultaneously, and the removal efficiencies under the high Cu2+ concentrations were higher than those under low Cu2+ concentrations. Results show that the root was the main section for accumulating Cu2+ and the data of Cu2+ uptake by perennial ryegrass fitted Michaelis-Menten kinetics equation. Perennial ryegrass were sensitive to Cu2+ treatment. Root elongation was reduced in Cu2+ treatment solutions, but the numbers of new-growth roots increased compared with those cultivated in control solution.

The adsorption of acid orange II onto modified peat-resin particles was examined in aqueous solution in a batch system. The Langmuir and Freundlich adsorption models were applied to describe the equilibrium isotherms. The pseudo-first-order, pseudo-second-order kinetic and the intraparticle diffusion models were used to describe the kinetic data. The results showed that both Langmuir and Freundlich adsorption models could be used to describe the adsorption of acid orange II onto modified peat-resin particles. The maximum adsorption capacity was 71.43 mg x g(-1). The data analysis indicated that the intraparticle diffusion model could fit the results of kinetic experiment well. The adsorption rate of acid orange II onto modified peat-resin particles is affected by the initial dye concentrations, sizes and doses of modified peat-resin particles and agitation rates. The surface of modified peat-resin particle is the major adsorption area.

Pot experiments with five legumes were conducted in five different amendment substrates for the reclamation of copper tailings in Tongling, Anhui province. The five tested legumes species are Glycine max, Phaseolus angularis, P. calcaratus, P. radiatus, P. mininus. The results showed that the main factors to restrict growing of the vegetation are poor nutrient and high concentration of Cu. The seeds of the legumes species could germinate, but they germinated later in the substrates with higher proportion of copper tailings than in the substrates with lower proportion of copper tailings. After clipping, G. max, P. angularis, P. calcaratus, P. radiatus were alive all the time, but some of the other two legumes species were dead because of the their non-adaptation to the copper tailings. At the same amendment group, the chlorophyll contents of G. max and P. calcaratus were higher than that of other three experimental species on the 50th day. The height and the biomass of G. max and P. calcaratus were higher than that of other three experimental species on the 70th day too. According to the biological characteristics of the five species during the growth periods about indexes of the seeding survival, chlorophyll content, height and biomass, G. max and P. calcaratus are more adaptive and tolerant than the other legumes and the TA75 amendment approach is the more reasonable for the reclamation of copper tailings.