The experimental results of flue gas desulphurization with caustic lime andhydrated lime activated by water spraying in a desulphurization reactor are presented. The effectsof Ca/S molar ratio, approach to saturation ...The experimental results of flue gas desulphurization with caustic lime andhydrated lime activated by water spraying in a desulphurization reactor are presented. The effectsof Ca/S molar ratio, approach to saturation of flue gas, SO_2 concentration and gas velocity onsulfur retention efficiency and calcium utilization rate are investigated. Desulphurizationcharacteristics of the two sorbents are compared. The mechanism of improving desulphurizationefficiency by water spraying is analyzed. The results show that the activities of two sorbents areimproved obviously by humidification with water spray and the caustic lime has better applicationprospect because of cheaper cost.展开更多
By measuring wetland plants chlorophyll content,malondialdehyde(MDA) content and superoxide dismutase(SOD) enzyme activity,the changes of wetland plant physiological characeristics under different power strength were ...By measuring wetland plants chlorophyll content,malondialdehyde(MDA) content and superoxide dismutase(SOD) enzyme activity,the changes of wetland plant physiological characeristics under different power strength were studied,and the mechanism of electric field on plant physiological characteristics was analyzed to provide a theoretical basis for the pollutant removal ability strengthening of artificial wetland under electricfield.The results showed that compared with the control plants,low-intensity-voltage(1 V and 3 V) had no significant effect on the normal physiological and biochemical indexes of the plants,and the growth trend was better than the control group;with the voltage increasing,plant chlorophyll content,MDA content and SOD activity were greatly affected,indicating that plants were under strong oxidative stress,and the growth was damaged.Therefore,a suitable electric field could enhance the sewage treatment effect of constructed wetland.展开更多
To probe the influence and the adverse-resistance characteristics of wetland plants in presence of silver nanoparticles (AgNPs), the changes in the physiological and biochemical characteristics (including the superoxi...To probe the influence and the adverse-resistance characteristics of wetland plants in presence of silver nanoparticles (AgNPs), the changes in the physiological and biochemical characteristics (including the superoxide dismutase (SOD) activity, catalase (CAT) activity, peroxidase (POD) activity, soluble protein content, and chlorophyll content) of Typha orientalis exposed to different concentrations of AgNPs solutions (0, 0.1, 1, 20 and 40 mg/L) were explored. Meantime, the accumulation of silver content in these plants was revealed. The results show that under low concentrations of AgNPs, the SOD and POD activities in the leaves of Typha orientalis are strengthened to different degrees. However, high concentrations of AgNPs inhibit the activities of SOD and POD. Under the stress of different concentrations of AgNPs, the CAT activities are inhibited initially and later recovered to some extent. Under the stress of low concentrations of AgNPs, the soluble protein content in the leaves of Typha orientalis increases significantly, but decreases more significantly with increasing concentrations of AgNPs. Low concentrations of AgNPs promote chlorophyll synthesis in the leaves of Typha orientalis , but the chlorophyll content subsequently falls to pre-stress levels. In contrast, high concentrations of AgNPs cause a certain inhibition to generate chlorophyll. Meanwhile, the results show that the silver concentrations of plant tissues increase with the exposure of concentrations of AgNPs and they have a positive relationship with the exposure of concentrations of AgNPs.展开更多
Modern hydrometallurgy has been developing for more than 100 years and the related articles keep piling up.Based on a bibliometric analysis of the articles in Hydrometallurgy,the most authoritative journal in the fiel...Modern hydrometallurgy has been developing for more than 100 years and the related articles keep piling up.Based on a bibliometric analysis of the articles in Hydrometallurgy,the most authoritative journal in the field of hydrometallurgy,we try to catch the research and development trends from a global perspective.Firstly,keywords burstness shows that rare earth,recycling,lithium,ionic liquid,and thorium are the hotspots in recent years,and the economic and technological reasons behind them were discussed in depth.Secondly,the proportion of biohydrometallurgy grows fast from 5%to 13%and the related articles are almost all about bioleaching.There are some new directions such as direct preparation of materials in hydrometallurgical processes and ion-imprinted techniques.Thirdly,the advanced instrument analysis methods such as XAFS(X-ray absorption fine structure),gene sequencing,and micro-CT promote the deep understanding of hydrometallurgy mechanism.Finally,the cooperation network and contribution of the main institutes were mapped.展开更多
Objective: To study the expression of activated epi-dermal growth factor receptor (EGFR) and transcrip-tion factor E2F (E2F) in Condyloma Accuminata(CA)patients. Methods: Immunofluorescent techniques were usedto inves...Objective: To study the expression of activated epi-dermal growth factor receptor (EGFR) and transcrip-tion factor E2F (E2F) in Condyloma Accuminata(CA)patients. Methods: Immunofluorescent techniques were usedto investigate the expression of activated EGFR andE2F in CA patients. Results: The expression of activated EGFR on themembrane of epithelial cells in CA lesions was sig-nificantly greater compared to expression levers inthe control group (P<0.01). Moreover, the co-expres-sion of activated EGFR and E2F was significantly in-creased compared to the control group (P<0.01). Conclusion: Our observations suggest that the in-crease in activated EGFR expression may stimulatehyperplasia in CA patients through the activation oftranscription factor E2F.展开更多
The energy budget and regulating factors were investigated over an estuarine wetland during one year of continuous measurement in 2006.The results show that the seasonal changes of the energy fluxes and Bowen ratio(β...The energy budget and regulating factors were investigated over an estuarine wetland during one year of continuous measurement in 2006.The results show that the seasonal changes of the energy fluxes and Bowen ratio(β) were greatly affected by incoming shortwave radiation and canopy growth.During the non-growing season and early-growing season, sensible heat(H) dominated the energy flux, and β could reach a maximum of 2.5, while during most of the growing season, latent heat dominated the energy flux and β fluctuated from 0.4 to 1.0.The energy budget ratio in growing season was about 0.76, and the value would be higher if heat exchange during tidal flooding was in-cluded.During tidal flooding days, β was slightly higher than that at exposure days in most cases.Vegetation cover seems exert little effect on energy partitioning except in March when the standing dead grass intercepted the incoming radiation that might reach the soil surface and reduce the turbulence between soil and atmosphere, thus suppressing the evaporation from the soil though the soil mositure was high at that time.展开更多
Objective To observe the characteristics of gene methylation in obese rats with phlegm-dampness syndrome induced by the high-fat diet, and to study the effect of Wen Dan Decoction on gene methylation after the interve...Objective To observe the characteristics of gene methylation in obese rats with phlegm-dampness syndrome induced by the high-fat diet, and to study the effect of Wen Dan Decoction on gene methylation after the intervention. Methods Methylation sites of genes were detected by the MeDIP-seq method. Bioinformatics method was used to analyze the gene methylation characteristics of obesity with phlegmdampness syndrome and the effect of Wen Dan Decoction. Results (1) There were 3 242 methylation differential loci in dietinduced obesity with phlegm-dampness syndrome, of which 1 243 were down-regulated and 1 999 were up-regulated, involving 1 579 differential genes. GO analysis showed that "offactory receptor activity" and others were enriched. The possible signal pathways involved were "Olfactory transduction""Tuberculosis""Systemic lupus erythematosus" and "Ribosome".(2) After the intervention of Wen Dan Decoction in obesity with phlegmdampness syndrome, 4 046 different methylation loci were obtained, including 1 067 down-regulated loci and 2 979 up-regulated loci, involving 2 068 genes. GO analysis showed that "offactory receptor activity" and others were enriched. These genes involved seven signaling pathways, such as "Metabolic pathways".(3) Between diet-induced obesity with phlegm-dampness syndrome and Wen Dan Decoction intervening obesity with the phlegm-dampness syndrome, 582 common genes of methylation differential genes were obtained. After the intervention of Wen Dan Decoction, the number of GO enrichment items was more than that of obesity with phlegm-dampness syndrome, and even the same GO enrichment items involved more genes. Conclusions The phlegm-dampness syndrome of obesityinduced by diet had the characteristics of gene methylation changes, and the intervention of Wen Dan Decoction could also affect the status of gene methylation. The genes affected by Wen Dan Decoction were closely related to the methylation gene of phlegm-dampness syndrome of obesity-induced by diet but covered a wider range.展开更多
Wetlands play a very important role in ecosystems. Qixinghe Wetland is a nature reserve area in northeastern China. In this paper, diatom communities and environmental qualities were investigated at eight sites in Qix...Wetlands play a very important role in ecosystems. Qixinghe Wetland is a nature reserve area in northeastern China. In this paper, diatom communities and environmental qualities were investigated at eight sites in Qixinghe Wetland. This study was to examine diatom species patterns in relation to environmental variables in wetlands, and to use diatoms as indicators to water quality in wetlands and wetland classification. Diatoms were sampled in summers and autumns in 2002 and 2004, during which 180 taxa were identified. Environmental variations in pH, temperature, biochemical oxygen demand (BOD), and chemical oxygen demand (COD) were measured. The seasonal composition and abundance of diatoms changed greatly during the study period. The relationship between diatoms and chemical water quality was estimated statistically. Canonical correspondence analysis (CCA) with forward selection and Monte Carlo permutation tests revealed that all water environmental variables changed during the study period (P<0.05). Among all the parameters, variation in BOD among the sites was a very important determinant of species composition according to the CCA, and BOD decreased from 2002 to 2004. Our results suggest that the water quality had improved during the three-year period because of enhanced environmental protection with less human disturbance. We conclude that diatoms can be used to indicate water quality and habitat conditions in this wetland.展开更多
Forest plays very important roles in global system with about 35% land area producing about 70% of total land net production. It is important to consider both elevated CO2 concentrations and different soil moisture wh...Forest plays very important roles in global system with about 35% land area producing about 70% of total land net production. It is important to consider both elevated CO2 concentrations and different soil moisture when the possible effects of elevated CO2 concentration on trees are assessed. In this study, we grew Cinnamomum camphora seedlings under two CO2 concentrations （350 μmol/mol and 500μmnol/mol） and three soil moisture levels [80%, 60% and 40% FWC （field water capacity）] to focus on the effects of exposure of trees to elevated CO2 on underground and aboveground plant growth, and its dependence on soil moisture. The results indicated that high CO2 concentration has no significant effects on shoot height but significantly impacts shoot weight and ratio of shoot weight to height under three soil moisture levels. The response of root growth to CO2 enrichment is just reversed, there are obvious effects on root length growth, but no effects on root weight growth and ratio of root weight to length. The CO2 enrichment decreased 20.42%, 32.78%, 20.59% of weight ratio of root to shoot under 40%, 60% and 80% FWC soil water conditions, respectively. And elevated CO2 concentration significantly increased the water content in aboveground and underground parts. Then we concluded that high CO2 concentration favours more tree aboveground biomass growth than underground biomass growth under favorable soil water conditions. And CO2 enrichment enhanced lateral growth of shoot and vertical growth of root. The responses of plants to elevated CO2 depend on soil water availability, and plants may benefit more from CO2 enrichment with sufficient water supply.展开更多
Synthesis of monoglycerides with Cinnamomum burmannii seeds oil and its application in moisturizing cream were studied. The results showed that the optimal transesterification conditions of synthesis of monoglycerides...Synthesis of monoglycerides with Cinnamomum burmannii seeds oil and its application in moisturizing cream were studied. The results showed that the optimal transesterification conditions of synthesis of monoglycerides with Cinnamomum burmannii seeds oil were as follows： the glycerol to oil molar ratio of 3 ： 1 ; NaOH catalyst dosage of 0.8% of the oil mass; reaction temperature of 180 ℃ for 3 hours; and the yield reached 62.6% . The crude product was purified by molecular distillation and the purity of the final product achieved 92.8%. Physicochemical properties of moisturizing cream prepared by using the final product can meet the requirements of China National Standard and the cosmetic product displayed good performance in application.展开更多
Five different sites with a soluble salt gradient of 3.0-17.7 g kg^-1 dry soil from the coast to the inland were selected, and the microbial population size, activity and diversity in the rhizospheres of five common p...Five different sites with a soluble salt gradient of 3.0-17.7 g kg^-1 dry soil from the coast to the inland were selected, and the microbial population size, activity and diversity in the rhizospheres of five common plant species and the adjacent bulk soils （non-rhizosphere） were compared in a degraded wetland of the Yellow River Delta, Shandong Province, China to study the effects of soil environment （salinity, seasonality, depth, and rhizosphere） on microbial communities and the wetland＇s ecological function, thus providing basic data for the bioremediation of degraded wetlands. There was a significant negative linear relationship between the salinity and the total number of microorganisms, overall microbial activity, or culturable microbial diversity. Salinity adversely affected the microbial community, and higher salinity levels resulted in smaller and less active microbial communities. Seasonal changes were observed in microbial activity but did not occur in the size and diversity. The microbial size, activity and diversity decreased with increasing soil depth. The size, activity and diversity of culturable microorganisms increased in the rhizospheres. All rhizospheres had positive effects on the microbial communities, and common seepweed had the highest rhizosphere effect. Three halophilic bacteria （Pseudomonas mendocina, Burkholderia glumae, and Acinetobacter johnsonii） were separated through BIOLOG identification, and common seepweed could be recommended for bioremediation of degraded wetlands in the Yellow River Delta.展开更多
The wetlands on the Zoige Plateau have experienced serious degradation,with most of the original marsh being converted to marsh meadow or meadow.Based on the 3 wetland degradation stages,we determined the effects of w...The wetlands on the Zoige Plateau have experienced serious degradation,with most of the original marsh being converted to marsh meadow or meadow.Based on the 3 wetland degradation stages,we determined the effects of wetland degradation on the structure and relative abundance of nitrogencycling(nitrogen-fixing,ammonia-oxidizing,and denitrifying) microbial communities in 3 soil types(intact wetland:marsh soil;early degrading wetland:marsh meadow soil;and degraded wetland:meadow soil) using 454-pyrosequencing.The structure and relative abundance of nitrogen-cycling microbial communities differed in the 3 soil types.Proteobacteria was the predominant phylum in most soil samples but the most abundant soil nitrogenfixing and denitrifying microbial bacteria differed at the class,order,family,and genus levels among the 3soil types.At the genus level,the majority of nitrogenfixing bacterium sequences related to Bradyrhizobium were from marsh and marsh meadow soils;whereas those related to Geobacter originated from meadow soil.The majority of ammonia-oxidizing bacterium sequences related to Nitrosospira were from marsh(except for the 40-60 cm layer),marsh meadow and meadow soils;whereas those related to Candidatus Solibacter originated from 40-60 cm layer of marsh soil.The majority of denitrifying bacterium sequences related to Candidatus Solibacter and Anaeromyxobacter were from marsh and meadow soils;whereas those related to Herbaspirillum originated from meadow soil.The distribution of operational taxonomic units(OTUs)and species were correlated with soil type based upon Venn and Principal Coordinates Analysis(PCoA).Changes in soil type,caused by different water regimes were the most important factors influencing compositional changes in the nitrogen-fixing,ammonia-oxidizing,and denitrifying microbial communities.展开更多
The Jamaica Bay ecosystem is a dichotomy. It encompasses more than 12,000 acres of coastal estuarine marshes and an ecological diversity rivaling any coastal environment in the world. It is considerably altered, and i...The Jamaica Bay ecosystem is a dichotomy. It encompasses more than 12,000 acres of coastal estuarine marshes and an ecological diversity rivaling any coastal environment in the world. It is considerably altered, and is affected by a variety of ecological insults directly related to the fact that more than 14 million people live in its vicinity. Environmental protection institutions responded to the challenge of protecting the bay, surrounding wetlands and recreational benefits by addressing the increasing load of contaminants into the ecosystem. Billions of dollars have been spent during the past five decades on restoration attempts, including upgrading wastewater treatment plantsand the closure of three major sanitary landfills. Even with the curtailment of untreated wastewater release and ending periodic dredging and filling programs, all activities that are necessary processes in maintaining an urban harbor, the Jamaica Bay ecosystem has reached a point where many believe it to be unrecoverable, requiring massive infusions of restoration dollars. This categorization has been perpetuated based on questionable data （the ＂myths＂） that, when investigated in rigorous scientific detail, prove to be unsubstantiated. In this paper, the origin of these myths and the scientific investigation that dispel them are discussed.展开更多
By the use of the software of ARCGIS, dynamic changes of the landscape elements, landscape structure, conversion processes of the landscape gradients and the responses of wetland eco-security to land use/cover changes...By the use of the software of ARCGIS, dynamic changes of the landscape elements, landscape structure, conversion processes of the landscape gradients and the responses of wetland eco-security to land use/cover changes (LUCC) in the western Jilin Province were studied from 1930 to 2000. The results show that the landscape elements of grassland, wetland, forestland and water area shrank rapidly, and wetlands underwent huge losses in the study period due to the conversion from wetland into arable land and grassland in large quantities. The responses of wetland eco-security to LUCC were inverse evolvement of wetland vegetation, loss of biodiversity, water deficiency in wetland ecosystem, the changes of the heterogeneity of wetlands and the fragmentation of the wetland habitats. Suggestions were given for protection of wetlands and the regional sustainable development.展开更多
文摘The experimental results of flue gas desulphurization with caustic lime andhydrated lime activated by water spraying in a desulphurization reactor are presented. The effectsof Ca/S molar ratio, approach to saturation of flue gas, SO_2 concentration and gas velocity onsulfur retention efficiency and calcium utilization rate are investigated. Desulphurizationcharacteristics of the two sorbents are compared. The mechanism of improving desulphurizationefficiency by water spraying is analyzed. The results show that the activities of two sorbents areimproved obviously by humidification with water spray and the caustic lime has better applicationprospect because of cheaper cost.
基金Supported by Natural Science Foundation of Shanghai(10ZR1400300 )Central University Special Foundation of Basic Research and Operating expenses+1 种基金Creative Group Foundation of the National Natural Science Foundation of China (50721006)Key Discipline construction Project of Shanghai (B604)~~
文摘By measuring wetland plants chlorophyll content,malondialdehyde(MDA) content and superoxide dismutase(SOD) enzyme activity,the changes of wetland plant physiological characeristics under different power strength were studied,and the mechanism of electric field on plant physiological characteristics was analyzed to provide a theoretical basis for the pollutant removal ability strengthening of artificial wetland under electricfield.The results showed that compared with the control plants,low-intensity-voltage(1 V and 3 V) had no significant effect on the normal physiological and biochemical indexes of the plants,and the growth trend was better than the control group;with the voltage increasing,plant chlorophyll content,MDA content and SOD activity were greatly affected,indicating that plants were under strong oxidative stress,and the growth was damaged.Therefore,a suitable electric field could enhance the sewage treatment effect of constructed wetland.
基金The National Natural Science Foundation of China(No.51479034,5151101102)
文摘To probe the influence and the adverse-resistance characteristics of wetland plants in presence of silver nanoparticles (AgNPs), the changes in the physiological and biochemical characteristics (including the superoxide dismutase (SOD) activity, catalase (CAT) activity, peroxidase (POD) activity, soluble protein content, and chlorophyll content) of Typha orientalis exposed to different concentrations of AgNPs solutions (0, 0.1, 1, 20 and 40 mg/L) were explored. Meantime, the accumulation of silver content in these plants was revealed. The results show that under low concentrations of AgNPs, the SOD and POD activities in the leaves of Typha orientalis are strengthened to different degrees. However, high concentrations of AgNPs inhibit the activities of SOD and POD. Under the stress of different concentrations of AgNPs, the CAT activities are inhibited initially and later recovered to some extent. Under the stress of low concentrations of AgNPs, the soluble protein content in the leaves of Typha orientalis increases significantly, but decreases more significantly with increasing concentrations of AgNPs. Low concentrations of AgNPs promote chlorophyll synthesis in the leaves of Typha orientalis , but the chlorophyll content subsequently falls to pre-stress levels. In contrast, high concentrations of AgNPs cause a certain inhibition to generate chlorophyll. Meanwhile, the results show that the silver concentrations of plant tissues increase with the exposure of concentrations of AgNPs and they have a positive relationship with the exposure of concentrations of AgNPs.
基金Project(2019JJ40377)supported by the Natural Science Foundation of Hunan Province,ChinaProject(2020CX026)supported by the Innovation-Driven Project of Central South University,ChinaProject(51934010)supported by the Major Program of National Natural Science Foundation of China。
文摘Modern hydrometallurgy has been developing for more than 100 years and the related articles keep piling up.Based on a bibliometric analysis of the articles in Hydrometallurgy,the most authoritative journal in the field of hydrometallurgy,we try to catch the research and development trends from a global perspective.Firstly,keywords burstness shows that rare earth,recycling,lithium,ionic liquid,and thorium are the hotspots in recent years,and the economic and technological reasons behind them were discussed in depth.Secondly,the proportion of biohydrometallurgy grows fast from 5%to 13%and the related articles are almost all about bioleaching.There are some new directions such as direct preparation of materials in hydrometallurgical processes and ion-imprinted techniques.Thirdly,the advanced instrument analysis methods such as XAFS(X-ray absorption fine structure),gene sequencing,and micro-CT promote the deep understanding of hydrometallurgy mechanism.Finally,the cooperation network and contribution of the main institutes were mapped.
文摘Objective: To study the expression of activated epi-dermal growth factor receptor (EGFR) and transcrip-tion factor E2F (E2F) in Condyloma Accuminata(CA)patients. Methods: Immunofluorescent techniques were usedto investigate the expression of activated EGFR andE2F in CA patients. Results: The expression of activated EGFR on themembrane of epithelial cells in CA lesions was sig-nificantly greater compared to expression levers inthe control group (P<0.01). Moreover, the co-expres-sion of activated EGFR and E2F was significantly in-creased compared to the control group (P<0.01). Conclusion: Our observations suggest that the in-crease in activated EGFR expression may stimulatehyperplasia in CA patients through the activation oftranscription factor E2F.
基金Under the auspices of National Natural Science Foundation of China (No. 30870409,40471087)Science and Technology Commission of Shanghai (No. 07DZ12038-2)the Program for New Century Excellent Talents in University (No.NCET-06-0364) funded by the Ministry of Education of China
文摘The energy budget and regulating factors were investigated over an estuarine wetland during one year of continuous measurement in 2006.The results show that the seasonal changes of the energy fluxes and Bowen ratio(β) were greatly affected by incoming shortwave radiation and canopy growth.During the non-growing season and early-growing season, sensible heat(H) dominated the energy flux, and β could reach a maximum of 2.5, while during most of the growing season, latent heat dominated the energy flux and β fluctuated from 0.4 to 1.0.The energy budget ratio in growing season was about 0.76, and the value would be higher if heat exchange during tidal flooding was in-cluded.During tidal flooding days, β was slightly higher than that at exposure days in most cases.Vegetation cover seems exert little effect on energy partitioning except in March when the standing dead grass intercepted the incoming radiation that might reach the soil surface and reduce the turbulence between soil and atmosphere, thus suppressing the evaporation from the soil though the soil mositure was high at that time.
基金the funding support from the National Natural Science Youth Foundation of China: Effect of Wen Dan Decoction on gene promoter methylations related to fat metabolism (No. 81302907)
文摘Objective To observe the characteristics of gene methylation in obese rats with phlegm-dampness syndrome induced by the high-fat diet, and to study the effect of Wen Dan Decoction on gene methylation after the intervention. Methods Methylation sites of genes were detected by the MeDIP-seq method. Bioinformatics method was used to analyze the gene methylation characteristics of obesity with phlegmdampness syndrome and the effect of Wen Dan Decoction. Results (1) There were 3 242 methylation differential loci in dietinduced obesity with phlegm-dampness syndrome, of which 1 243 were down-regulated and 1 999 were up-regulated, involving 1 579 differential genes. GO analysis showed that "offactory receptor activity" and others were enriched. The possible signal pathways involved were "Olfactory transduction""Tuberculosis""Systemic lupus erythematosus" and "Ribosome".(2) After the intervention of Wen Dan Decoction in obesity with phlegmdampness syndrome, 4 046 different methylation loci were obtained, including 1 067 down-regulated loci and 2 979 up-regulated loci, involving 2 068 genes. GO analysis showed that "offactory receptor activity" and others were enriched. These genes involved seven signaling pathways, such as "Metabolic pathways".(3) Between diet-induced obesity with phlegm-dampness syndrome and Wen Dan Decoction intervening obesity with the phlegm-dampness syndrome, 582 common genes of methylation differential genes were obtained. After the intervention of Wen Dan Decoction, the number of GO enrichment items was more than that of obesity with phlegm-dampness syndrome, and even the same GO enrichment items involved more genes. Conclusions The phlegm-dampness syndrome of obesityinduced by diet had the characteristics of gene methylation changes, and the intervention of Wen Dan Decoction could also affect the status of gene methylation. The genes affected by Wen Dan Decoction were closely related to the methylation gene of phlegm-dampness syndrome of obesity-induced by diet but covered a wider range.
基金Supported by the National Natural Science Foundation of China (Nos.30870157, 31070183)the Natural Science Foundation of Heilongjiang Province, China (No. C200828)+1 种基金the Aid Program for Science and Technology Innovative Research Team (No. KJTD2011-2)the Projects in advance of Harbin Normal University
文摘Wetlands play a very important role in ecosystems. Qixinghe Wetland is a nature reserve area in northeastern China. In this paper, diatom communities and environmental qualities were investigated at eight sites in Qixinghe Wetland. This study was to examine diatom species patterns in relation to environmental variables in wetlands, and to use diatoms as indicators to water quality in wetlands and wetland classification. Diatoms were sampled in summers and autumns in 2002 and 2004, during which 180 taxa were identified. Environmental variations in pH, temperature, biochemical oxygen demand (BOD), and chemical oxygen demand (COD) were measured. The seasonal composition and abundance of diatoms changed greatly during the study period. The relationship between diatoms and chemical water quality was estimated statistically. Canonical correspondence analysis (CCA) with forward selection and Monte Carlo permutation tests revealed that all water environmental variables changed during the study period (P<0.05). Among all the parameters, variation in BOD among the sites was a very important determinant of species composition according to the CCA, and BOD decreased from 2002 to 2004. Our results suggest that the water quality had improved during the three-year period because of enhanced environmental protection with less human disturbance. We conclude that diatoms can be used to indicate water quality and habitat conditions in this wetland.
基金Project supported by the National Natural Science Foundation of China (Nos. 30170161 and 90102015) and the Doctoral Disciplines Programs Foundation of Ministry of Education of China (No. 20030335043)
文摘Forest plays very important roles in global system with about 35% land area producing about 70% of total land net production. It is important to consider both elevated CO2 concentrations and different soil moisture when the possible effects of elevated CO2 concentration on trees are assessed. In this study, we grew Cinnamomum camphora seedlings under two CO2 concentrations （350 μmol/mol and 500μmnol/mol） and three soil moisture levels [80%, 60% and 40% FWC （field water capacity）] to focus on the effects of exposure of trees to elevated CO2 on underground and aboveground plant growth, and its dependence on soil moisture. The results indicated that high CO2 concentration has no significant effects on shoot height but significantly impacts shoot weight and ratio of shoot weight to height under three soil moisture levels. The response of root growth to CO2 enrichment is just reversed, there are obvious effects on root length growth, but no effects on root weight growth and ratio of root weight to length. The CO2 enrichment decreased 20.42%, 32.78%, 20.59% of weight ratio of root to shoot under 40%, 60% and 80% FWC soil water conditions, respectively. And elevated CO2 concentration significantly increased the water content in aboveground and underground parts. Then we concluded that high CO2 concentration favours more tree aboveground biomass growth than underground biomass growth under favorable soil water conditions. And CO2 enrichment enhanced lateral growth of shoot and vertical growth of root. The responses of plants to elevated CO2 depend on soil water availability, and plants may benefit more from CO2 enrichment with sufficient water supply.
文摘Synthesis of monoglycerides with Cinnamomum burmannii seeds oil and its application in moisturizing cream were studied. The results showed that the optimal transesterification conditions of synthesis of monoglycerides with Cinnamomum burmannii seeds oil were as follows： the glycerol to oil molar ratio of 3 ： 1 ; NaOH catalyst dosage of 0.8% of the oil mass; reaction temperature of 180 ℃ for 3 hours; and the yield reached 62.6% . The crude product was purified by molecular distillation and the purity of the final product achieved 92.8%. Physicochemical properties of moisturizing cream prepared by using the final product can meet the requirements of China National Standard and the cosmetic product displayed good performance in application.
基金Supported by the National Natural Science Foundation of China (No.30570340)the National Key Technology R&DProgram of China (No.2006BAC01A13)+1 种基金the Program for New Century Excellent Talents in University, China (NCET-06-0599)the Cheung Kong Scholar Program of the Education Ministry of China
文摘Five different sites with a soluble salt gradient of 3.0-17.7 g kg^-1 dry soil from the coast to the inland were selected, and the microbial population size, activity and diversity in the rhizospheres of five common plant species and the adjacent bulk soils （non-rhizosphere） were compared in a degraded wetland of the Yellow River Delta, Shandong Province, China to study the effects of soil environment （salinity, seasonality, depth, and rhizosphere） on microbial communities and the wetland＇s ecological function, thus providing basic data for the bioremediation of degraded wetlands. There was a significant negative linear relationship between the salinity and the total number of microorganisms, overall microbial activity, or culturable microbial diversity. Salinity adversely affected the microbial community, and higher salinity levels resulted in smaller and less active microbial communities. Seasonal changes were observed in microbial activity but did not occur in the size and diversity. The microbial size, activity and diversity decreased with increasing soil depth. The size, activity and diversity of culturable microorganisms increased in the rhizospheres. All rhizospheres had positive effects on the microbial communities, and common seepweed had the highest rhizosphere effect. Three halophilic bacteria （Pseudomonas mendocina, Burkholderia glumae, and Acinetobacter johnsonii） were separated through BIOLOG identification, and common seepweed could be recommended for bioremediation of degraded wetlands in the Yellow River Delta.
基金financially supported by the 11th Five Years Key Programs for Science and Technology Development of China (Grant No.2007BAC18B03)
文摘The wetlands on the Zoige Plateau have experienced serious degradation,with most of the original marsh being converted to marsh meadow or meadow.Based on the 3 wetland degradation stages,we determined the effects of wetland degradation on the structure and relative abundance of nitrogencycling(nitrogen-fixing,ammonia-oxidizing,and denitrifying) microbial communities in 3 soil types(intact wetland:marsh soil;early degrading wetland:marsh meadow soil;and degraded wetland:meadow soil) using 454-pyrosequencing.The structure and relative abundance of nitrogen-cycling microbial communities differed in the 3 soil types.Proteobacteria was the predominant phylum in most soil samples but the most abundant soil nitrogenfixing and denitrifying microbial bacteria differed at the class,order,family,and genus levels among the 3soil types.At the genus level,the majority of nitrogenfixing bacterium sequences related to Bradyrhizobium were from marsh and marsh meadow soils;whereas those related to Geobacter originated from meadow soil.The majority of ammonia-oxidizing bacterium sequences related to Nitrosospira were from marsh(except for the 40-60 cm layer),marsh meadow and meadow soils;whereas those related to Candidatus Solibacter originated from 40-60 cm layer of marsh soil.The majority of denitrifying bacterium sequences related to Candidatus Solibacter and Anaeromyxobacter were from marsh and meadow soils;whereas those related to Herbaspirillum originated from meadow soil.The distribution of operational taxonomic units(OTUs)and species were correlated with soil type based upon Venn and Principal Coordinates Analysis(PCoA).Changes in soil type,caused by different water regimes were the most important factors influencing compositional changes in the nitrogen-fixing,ammonia-oxidizing,and denitrifying microbial communities.
文摘The Jamaica Bay ecosystem is a dichotomy. It encompasses more than 12,000 acres of coastal estuarine marshes and an ecological diversity rivaling any coastal environment in the world. It is considerably altered, and is affected by a variety of ecological insults directly related to the fact that more than 14 million people live in its vicinity. Environmental protection institutions responded to the challenge of protecting the bay, surrounding wetlands and recreational benefits by addressing the increasing load of contaminants into the ecosystem. Billions of dollars have been spent during the past five decades on restoration attempts, including upgrading wastewater treatment plantsand the closure of three major sanitary landfills. Even with the curtailment of untreated wastewater release and ending periodic dredging and filling programs, all activities that are necessary processes in maintaining an urban harbor, the Jamaica Bay ecosystem has reached a point where many believe it to be unrecoverable, requiring massive infusions of restoration dollars. This categorization has been perpetuated based on questionable data （the ＂myths＂） that, when investigated in rigorous scientific detail, prove to be unsubstantiated. In this paper, the origin of these myths and the scientific investigation that dispel them are discussed.
基金U nderthe auspices ofK now ledge Innovation Program ofC hinese A cadem y ofSciences (N o.K ZC X 2-308-3-5)
文摘By the use of the software of ARCGIS, dynamic changes of the landscape elements, landscape structure, conversion processes of the landscape gradients and the responses of wetland eco-security to land use/cover changes (LUCC) in the western Jilin Province were studied from 1930 to 2000. The results show that the landscape elements of grassland, wetland, forestland and water area shrank rapidly, and wetlands underwent huge losses in the study period due to the conversion from wetland into arable land and grassland in large quantities. The responses of wetland eco-security to LUCC were inverse evolvement of wetland vegetation, loss of biodiversity, water deficiency in wetland ecosystem, the changes of the heterogeneity of wetlands and the fragmentation of the wetland habitats. Suggestions were given for protection of wetlands and the regional sustainable development.
