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Zhang Y.,Tsinghua University | Chen L.,Tsinghua University | Chen L.,Yangtze University | Sun R.,Peking University | And 4 more authors.
Applied Microbiology and Biotechnology | Year: 2015

Under the increasing pressure of human activities, Hangzhou Bay has become one of the most seriously polluted waters along China’s coast. Considering the excessive inorganic nitrogen detected in the bay, in this study, the impact of an effluent from a coastal industrial park on ammonia-oxidizing microorganisms (AOMs) of the receiving area was interpreted for the first time by molecular technologies. Revealed by real-time PCR, the ratio of archaeal amoA/bacterial amoA ranged from 5.68 × 10−6 to 4.79 × 10−5 in the activated sludge from two wastewater treatment plants (WWTPs) and 0.54–3.44 in the sediments from the effluent receiving coastal area. Analyzed by clone and pyrosequencing libraries, genus Nitrosomonas was the predominant ammonia-oxidizing bacteria (AOB), but no ammonia-oxidizing archaea (AOA) was abundant enough for sequencing in the activated sludge from the WWTPs; genus Nitrosomonas and Nitrosopumilus were the dominant AOB and AOA, respectively, in the coastal sediments. The different abundance of AOA but similar structure of AOB between the WWTPs and nearby coastal area probably indicated an anthropogenic impact on the microbial ecology in Hangzhou Bay. © 2015, Springer-Verlag Berlin Heidelberg.


Guan D.,China Agricultural University | Guan D.,Rural Energy and Environment Agency | Zhang Y.,China Agricultural University | Al-Kaisi M.M.,Iowa State University | And 3 more authors.
Soil and Tillage Research | Year: 2015

Water shortage has limited the agricultural sustainable development of North China Plain (NCP), where winter wheat (. Triticum aestivum L.) is the major irrigated crop that consumes 60-80% of available deep groundwater for agriculture production, leading to the significant decline in groundwater resource. The protection of water resources is important for the sustainable development of agriculture in NCP. The objective of this study was to evaluate the effect of plow-tillage (PT), rotary-tillage (RT) and no-tillage (NT) on root growth, water consumption characteristics, grain yield, water use and water use efficiency (WUE) under rain-fed condition conducted in a field with 20-year of rotary tillage history. Findings of this research show that plow-tillage (PT) and rotary-tillage (RT) decreased the soil bulk density in the 0-20. cm soil depth and the penetration resistance in the 0-30. cm soil depth. During two growth seasons, PT had greater root weight density (RWD), root length density (RLD) and root surface density (RSD) than those under NT across the 0-110. cm soil profile at the tillering stage and in the 0-40. cm soil profile at the flowering stage, respectively. However, RWD, RLD and RSD of PT were lower than NT at 0-10. cm soil depth and greater at 10-20. cm soil depth at the ripening stage. Similar trends were observed under RT compared with NT. Soil water content (SWC) under PT and RT were lower compared with NT from tillering to flowering stage across 0-110. cm, but higher than under NT in 0-20. cm soil profile at ripening stage. Evapotranspiration (ET) values under PT were higher than under NT from sowing to flowering stages, but significantly lower at the ripening stage. Moreover, tillage practices had no notable influences on pre-planting soil water storage and total ET under rain-fed condition during two growing season, but PT significantly enhanced grain yield through higher spike number and grain weight compared with NT, which led to higher WUE under PT. The findings of this study show that PT practice can reduce soil bulk density and penetration resistance at the tillage zone, which can lead to greater RWD, RLD and RSD and greater ET from tillering to flowering stage. This can increase plant population and cause greater WUE and grain yield under rain-fed condition. © 2014 Elsevier B.V.


Wang S.,China University of Geosciences | Wu W.,China Institute of Water Resources and Hydropower Research | Wu W.,Engineering Technology Research Center Explor Utiliz Non Conventional Water Rsrc Water Use Efficiency | Liu F.,China University of Geosciences | And 4 more authors.
Journal of Contaminant Hydrology | Year: 2015

Seen as a solution to water shortages, wastewater reuse for crop irrigation does however poses a risk owing to the potential release of organic contaminants into soil and water. The frequency of detection (FOD), concentration, and migration of nonylphenol (NP) isomers in reclaimed water (FODRW), surface water (FODSW), and groundwater (FODGW) were investigated in a long-term wastewater irrigation area in Beijing. The FODRW, FODSW and FODGW of any or all of 12 NP isomers were 66.7% to 100%, 76.9% to 100% and 13.3% to 60%, respectively. The mean (± standard deviation) NP concentrations of the reclaimed water, surface water, and groundwater (NPRW, NPSW, NPGW, repectively) were 469.4 ± 73.4 ng L- 1, 694.6 ± 248.7 ng- 1 and 244.4 ± 230.8 ng- 1, respectively. The existence of external pollution sources during water transmission and distribution resulted in NPSW exceeding NPRW. NP distribution in groundwater was related to the duration and quantity of wastewater irrigation, the sources of aquifer recharge, and was seen to decrease with increasing aquifer depth. Higher riverside infiltration rate nearby leads to higher FODGW values. The migration rate of NP isomers was classified as high, moderate or low. © 2015 Elsevier B.V. All rights reserved.


Yin S.,China University of Geosciences | Wu W.,China Institute of Water Resources and Hydropower Research | Wu W.,Engineering Technique Research Center for the Exploration and Utilization of Non Conventional Water Resources and Water Use Efficiency | Liu H.,Engineering Technique Research Center for the Exploration and Utilization of Non Conventional Water Resources and Water Use Efficiency | Bao Z.,Rural Energy and Environment Agency
Journal of Contaminant Hydrology | Year: 2016

Reclaimed water reuse is an effective method of alleviating agricultural water shortages, which entails some potential risks for groundwater. In this study, the impacts of wastewater reuse on groundwater were evaluated by combination of groundwater chemistry and isotopes. In reclaimed water infiltration, salt composition was affected not only by ion exchange and dissolution equilibrium but also by carbonic acid equilibrium. The dissolution and precipitation of calcites and dolomites as well as exchange and adsorption between Na and Ca/Mg were simultaneous, leading to significant changes in Na/Cl, (Ca + Mg)/Cl, electrical conductivity (EC) and sodium adsorption ratio (SAR). The reclaimed water was of the Na-Mg-Ca-HCO3-Cl type, and groundwater recharged by reclaimed water was of the Na-Mg-HCO3 and Mg-Na-HCO3 types. The hydrogeological conditions characterized by sand-clay alternation led to both total nitrogen (TN) and total phosphorus (TP) removal efficiencies > 95%, and there was no significant difference in those contents between aquifers recharged by precipitation and reclamation water. > 40 years of long-term infiltration and recharge from sewage and reclaimed water did not cause groundwater contamination by nitrogen, phosphorus and heavy metals. These results indicate that characteristics of the study area, such as the lithologic structure with sand-clay alternation, relatively thick clay layer, and relatively large groundwater depth have a significant role in the high vulnerability. © 2016 Elsevier B.V.


PubMed | Engineering Technique Research Center for the Exploration and Utilization of Non Conventional Water Resources and Water Use Efficiency, Rural Energy and Environment Agency, China Institute of Water Resources and Hydropower Research and China University of Geosciences
Type: | Journal: Journal of contaminant hydrology | Year: 2016

Reclaimed water reuse is an effective method of alleviating agricultural water shortages, which entails some potential risks for groundwater. In this study, the impacts of wastewater reuse on groundwater were evaluated by combination of groundwater chemistry and isotopes. In reclaimed water infiltration, salt composition was affected not only by ion exchange and dissolution equilibrium but also by carbonic acid equilibrium. The dissolution and precipitation of calcites and dolomites as well as exchange and adsorption between Na and Ca/Mg were simultaneous, leading to significant changes in Na/Cl, (Ca+Mg)/Cl, electrical conductivity (EC) and sodium adsorption ratio (SAR). The reclaimed water was of the Na-Mg-Ca-HCO


PubMed | Water Resources University, Engineering Technique Research Center for the Exploration and Utilization of Non Conventional Water Resources and Water Use Efficiency, Rural Energy and Environment Agency, China Institute of Water Resources and Hydropower Research and China University of Geosciences
Type: | Journal: Journal of contaminant hydrology | Year: 2015

Seen as a solution to water shortages, wastewater reuse for crop irrigation does however poses a risk owing to the potential release of organic contaminants into soil and water. The frequency of detection (FOD), concentration, and migration of nonylphenol (NP) isomers in reclaimed water (FODRW), surface water (FODSW), and groundwater (FODGW) were investigated in a long-term wastewater irrigation area in Beijing. The FODRW, FODSW and FODGW of any or all of 12 NP isomers were 66.7% to 100%, 76.9% to 100% and 13.3% to 60%, respectively. The mean (standard deviation) NP concentrations of the reclaimed water, surface water, and groundwater (NPRW, NPSW, NPGW, repectively) were 469.473.4 ng L(-1), 694.6248.7 ng(-1) and 244.4230.8 ng(-1), respectively. The existence of external pollution sources during water transmission and distribution resulted in NPSW exceeding NPRW. NP distribution in groundwater was related to the duration and quantity of wastewater irrigation, the sources of aquifer recharge, and was seen to decrease with increasing aquifer depth. Higher riverside infiltration rate nearby leads to higher FODGW values. The migration rate of NP isomers was classified as high, moderate or low.


Zheng S.-A.,Rural Energy and Environment Agency | Zheng S.-A.,Agro Environmental Protection Institute | Han Y.-L.,Chinese Association of Agricultural Science Society | Zheng X.-Q.,Agro Environmental Protection Institute
Huanjing Kexue/Environmental Science | Year: 2014

Gaseous Hg can evaporate and enter the plants through the stomata of plat leaves, which will cause a serious threat to local food safety and human health. For the risk assessment, this study aimed to characterize atmospheric mercury (Hg) as well as its accumulation in 5 leafy vegetables (spinach, edible amaranth, rape, lettuce, allium tuberosum) from sewage-irrigated area of Tianjin City. Bio-monitoring sites were located in paddy (wastewater irrigation for 30 a), vegetables (wastewater irrigation for 15 a) and grass (control) fields. Results showed that after long-term wastewater irrigation, the mean values of mercury content in paddy and vegetation fields were significantly higher than the local background value and the national soil environment quality standard value for mercury in grade I, but were still lower than grade II. Soil mercury contents in the studied control grass field were between the local background value and the national soil environment quality standard grade I. Besides, the atmospheric environment of paddy and vegetation fields was subjected to serious mercury pollution. The mean values of mercury content in the atmosphere of paddy and vegetation fields were 71.3 ng·m-3 and 39.2 ng·m-3, respectively, which were markedly higher than the reference gaseous mercury value on the north sphere of the earth (1.5-2.0 ng·m-3). The mean value of ambient mercury in the control grass fields was 9.4 ng·m-3. In addition, it was found that the mercury content in leafy vegetables had a good linear correlation with the ambient total gaseous mercury (the data was transformed into logarithms as the dataset did not show a normal distribution). The comparison among 5 vegetables showed that the accumulations of mercury in vegetables followed this order: spinach>edible amaranth>allium tuberosum>rape>lettuce. Median and mean values of mercury contents in spinach and edible amaranth were greater than the hygienic standard for the allowable limit of mercury in food. Spinach appeared to accumulate more mercury than the other four vegetables, in which the median and mean mercury content were both higher than 20 μg·kg-1. The mercury concentrations in rape, lettuce and allium tuberosum were lower than the standard. Moreover, test results indicated that the Hg content in leafy vegetables was mainly the gaseous mercury through leaf adsorption but not the Hg particulates. This study clearly manifested that there should be a great concern on the pollution risk of both air-and soil borne mercury when cultivating leafy vegetables in long-term wastewater-irrigated area. ©, 2014, Science Press. All right reserved.


Jiang L.,Chinese Academy of Agricultural Sciences | Zhang H.-B.,Rural Energy and Environment Agency | Li G.,Chinese Academy of Agricultural Sciences | Chen B.-R.,Chinese Academy of Agricultural Sciences
Sensor Letters | Year: 2014

Time-series MODIS NDVI datasets for 2000-2009 were used in this study to investigate the characteristics of spatial-temporal changes in annual NDVImax for six typical grassland types, i.e., up-land meadows, low-land meadows, temperate meadow steppes, temperate steppes, desert steppes, and steppe deserts of the Xilingol grasslands, in Inner Mongolia, China. The analysis focused on the spatial change trends, the standard deviations and the occurrence time points of annual NDVImax for 2000-2009. The results indicated that too much utilization pressure has been put on the eastern research area, including up-land meadows, low-land meadows, temperate meadow steppes and the south and north parts of the temperate steppes; the work of vegetation protection and restoration has been remarkable in the central research area, including part of the desert steppe and the temperate steppe, and the changes in different types of grassland had been stable in total biomass. In terms of the changes in grassland areas over different grades, areas with annual NDVImax values in (0.1, 0.2], (0.6, 0.7] decreased, and areas with annual NDVImax values in (0.2, 0.6] increased for the study period. Insofar as space is concerned, deteriorating grasslands account for about 6.79% of the total area; restoring grasslands takes up 9.34%, Furthermore, there is about 82.14% of grassland where the annual NDVImax occurs between the 193rd day and the 241st day in each year, indicating that this period is the most important growing season for Xilingol grasslands. Copyright © 2014 American Scientific Publishers.


Bian J.,Nankai University | Bai H.,Nankai University | Li W.,Nankai University | Yin J.,Rural Energy and Environment Agency | Xu H.,Nankai University
Journal of Cleaner Production | Year: 2016

The number of waste mobile phones (WMPs) has increased dramatically in recent years. A complete recycling network is being developed in China, and the WMP recycling process will need to be industrialized. WMPs are valuable, but the potential environmental pressures resulting from recycling processes are currently not well understood. Three recycling scenarios were constructed to represent different current WMP treatment methods, and life-cycle assessments of the environmental impacts of the scenarios were performed. All three scenarios offered environmental benefits, but the scale of the benefits decreased in the order scenario 3 > scenario 2 > scenario 1. Recycling printed circuit boards and metals in the lithium batteries, possible because of the modularization process, was most environmentally beneficial. Environmental impacts were divided into 10 subcategories: recycling decreased the impacts of acidification and nitrification, carcinogenic effects, climate change, ecotoxicity, fossil fuel use, inorganic respiratory effects, and mineral effects more than the impacts of the other categories. The industrialization of WMP recycling should be based on a "manual disassembly plus modularized recycling" model (scenario 3). These results will allow decision-makers involved in the disposal of WMPs to improve the efficiency with which resources (including energy) can be recycled from WMPs. © 2016 Elsevier Ltd.


Li W.,Nankai University | Bai H.,Nankai University | Yin J.,Nankai University | Yin J.,Rural Energy and Environment Agency | Xu H.,Nankai University
Journal of Cleaner Production | Year: 2016

The sharp increase in car ownership that has occurred in China in recent years has led to a rapid increase in the number of end-of-life vehicles (ELVs). Life cycle analysis, in terms of the environmental impact and the ability to recycle and recover resources, was performed on a whole car in this study. Three scenarios were used to represent different technological levels of recycling ELVs. The major environmental impact of the ELV recycling system in China was found to be the human toxicity potential. It was found that recycling automotive shredder residues (ASRs), glass, plastic, wire harnesses, and various metal components during ELV recycling would decrease the amounts of raw materials and energy consumed in China. Moreover, it was found that decreasing the amount of energy consumed by recycling materials and remanufacturing engines would decrease pollutant emissions in China. The analysis showed that improving the engine remanufacturing, the recovery of nonmetallic materials and recycling ASRs would effectively improve the recovery of resources and increase the environmental benefits. Measures are proposed that the ELV recycling industry in China should take to decrease the environmental impact. © 2016 Elsevier Ltd.

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