Heavy metal pollution in agricultural water resources is very serious in re- cent years, resulting in large losses of the agricultural economy and endangering human life and health. Due to the advantages of low cost, ...Heavy metal pollution in agricultural water resources is very serious in re- cent years, resulting in large losses of the agricultural economy and endangering human life and health. Due to the advantages of low cost, high efficiency and less secondary pollution, microbial ramediation technology is widely used in the treatment of heavy metal pollution in agricultural water resources. At present, with the progress of modern biotechnology, microbial remediation of heavy metals in agricul- tural water resources has grown rapidly. The sources and status quo of heavy met- al pollution in agricultural water resources at home and aboard, and the principles of microbial remediation of heavy metals pollution in agricultural water resources were reviewed in this paper, as well as the several common microbial remediation technology of heavy metals in agricultural water resources. Additionally, the further research work of heavy metal contaminated agricultural water resources by microbial ramediation were prospected.展开更多
The monitored soil samples were collected from Heihui irrigated area, Jiaokou irrigated area, Qianhe river valley and Jinghe river valley (hereafter Heihui, Jiaokou, Qianhe and Jinghe for short respectively) of Guan...The monitored soil samples were collected from Heihui irrigated area, Jiaokou irrigated area, Qianhe river valley and Jinghe river valley (hereafter Heihui, Jiaokou, Qianhe and Jinghe for short respectively) of Guanzhong District. According to the Environment Quality Standard for Soil (GB 15618-1995II), we evaluated the pollution status of heavy metals (Cd, As, Cr and Pb) that could seriously endanger soil environment and human health by using single-factor index and synthetic pollution index methods. The results indicate that the synthetic pollution indices P of soil heavy metals are less than 0.7 in Heihui, Jiaokou, Qianhe and Jinghe of Guanzhong, the single-factor indices Pi of soil heavy metals of most soil samples are less than 0.7, so the soil environmental quality is in a good condition in Guanzhong on the whole; the enrichment degree of soil heavy metals is in the order of Heihui, Jinghe, Qianhe and Jiaokou; the contaminated degree of soil heavy metals has the feature of Cd 〉 As 〉 Cr 〉 Pb; heavy metals contents in the cultivated horizon soil are generally higher than those in its underlayer soil, heavy metals contents of soil have the characteristic of enriching towards the cultivated horizon; Cd exceeds standard in the soil samples HS07a, b and HS08a, b at the Yangtao orchard in Heihui and in the soil sample QHS01a at the suburban vegetable plot in Qianhe, which was mainly caused by the long-term irrational use of chemical fertilizer and pesticide.展开更多
According to the historical changes of coastal lines, seven soil sampling districts, from land to sea, were arranged in Dongtai City, Jiangsu Province to sample soils from surface and profile. Concentrations of seven ...According to the historical changes of coastal lines, seven soil sampling districts, from land to sea, were arranged in Dongtai City, Jiangsu Province to sample soils from surface and profile. Concentrations of seven major heavy metals (HMs), granularity, pH, organic matters and C/N of the soil samples were analyzed. Results show that concentrations of heavy metals in agricultural land present a certain spatial variance, decreasing from land to sea. Pollution assessment indicates that the agricultural soils were not polluted by HMs, but the potential pollution of Cu and Hg needs to be alerted. Different HMs accumulate in the surface and sub-surface of the soil profiles, and concentrations of Hg and Pb decrease significantly with the increment of soil depth. Concentrations of HMs exhibit a significantly negative correlation to pH, but have no significant relation with organic matters in soil. Principle component analysis show that the concentrations of HMs relate to the land use history. Concentrations of Hg, Ni and Cr in soil are closely related with land use history, and concentrations of Pb, Cu and Cr are affected by land use history as well as other factors. However, there is no significant relation between concentration of As and land use history.展开更多
Using data of 6 pollution-free agricultural product bases in Guangxi Zhuang Autonomous Region,this paper analyzed content of heavy metals,including arsenic(As),mercury(Hg),lead(Pb),cadmium(Cd),and chromium(Cr) in soil...Using data of 6 pollution-free agricultural product bases in Guangxi Zhuang Autonomous Region,this paper analyzed content of heavy metals,including arsenic(As),mercury(Hg),lead(Pb),cadmium(Cd),and chromium(Cr) in soil.After Pb,Cd,Cr,Hg and As content in soil is determined,it evaluated the pollution of soil using single factor pollution index method and Nemerow synthetic pollution index method in combination with evaluation standard of heavy metals in soil and grading standard for soil pollution.Analysis results indicate that As,Hg,Pb,Cd,Cr content is different in pollution-free agricultural product bases,but all conform to related standards and there is no standard exceeding problem.It is concluded that the quality of soil in pollution-free agricultural product bases is excellent,not polluted and completely meet requirements of evaluation standards,and suitable for developing pollution-free agricultural products.展开更多
A total of 219 agricultural soil and 48 vegetable samples were collected from the midstream and downstream of the Xiangjiang River(the Hengyang-Changsha section)in Hunan Province.The accumulation characteristics,spa...A total of 219 agricultural soil and 48 vegetable samples were collected from the midstream and downstream of the Xiangjiang River(the Hengyang-Changsha section)in Hunan Province.The accumulation characteristics,spatial distribution and potential risk of heavy metals in the agricultural soils and vegetables were depicted.There are higher accumulations of heavy metals such as As,Cd,Cu,Ni,Pb and Zn in agricultural soils,and the contents of Cd(2.44 mg kg^-1 ),Pb(65.00 mg kg^-1 )and Zn(144.13 mg kg^-1 )are 7.97,3.69 and 1.63 times the corresponding background contents in soils of Hunan Province,respectively. 13.2%of As,68.5%of Cd,2.7%of Cu,2.7%of Ni,8.7%of Pb and 15.1%of Zn in soil samples from the investigated sites exceeded the maximum allowable heavy metal contents in the China Environmental Quality Standard for Soils(GB15618-1995,Grade Ⅱ).The pollution characteristics of multi-metals in soils are mainly due to Cd.The contents of As,Cd,Cu,Pb and Zn in vegetable soils are significantly higher than the contents in paddy soils.95.8%, 68.8%,10.4%and 95.8%of vegetable samples exceeded the Maximum Levels of Contaminants in Foods(GB2762-2005)for As,Cd,Ni and Pb concentrations,respectively.There are significantly positive correlations between the concentrations of Cd,Pb and Zn in vegetables and the concentrations in the corresponding vegetable soils(p〈0.01).It is very necessary to focus on the potential risk of heavy metals for food safety and human health in agricultural soils and vegetables in the midstream and downstream of the Xiangjiang River,Hunan Province of China.展开更多
A total of 118 of agricultural soil and 43 of vegetable samples were collected from Dongguan City, Guangdong, China. The spatial distribution, sources, accumulation characteristics and potential risk of heavy metals i...A total of 118 of agricultural soil and 43 of vegetable samples were collected from Dongguan City, Guangdong, China. The spatial distribution, sources, accumulation characteristics and potential risk of heavy metals in the agricultural soils and vegetables were depicted in details by three different approaches, including total contents of eight metal elements in soils and vegetables, GIS maps and multivariate analysis of heavy metals in soils in the study. The results show that there are higher accumulation of heavy metals such as Cu, Zn, Ni, Pb, Cd and Hg in agricultural soils, and the contents of Pb (65.38 mg kg^-1) and Hg (0.24 mg kg^-1) are 1.82 and 2.82 times of the background contents of the corresponding heavy metals in soils of Guangdong Province, respectively. There are about 3.4% of Cu, 5.9% of Ni, 1.7% of Cd and 28% of Hg in all collected soil samples from all investigated sites which have overran the contents for heavy metals of the China Environmental Quality Standard for Soils (GB15618-1995, Grade Ⅱ). The pollution characteristics of multi-metals in soils are mainly reflected by Hg. There are different sources to eight metal elements in soils, Cu, Zn, Ni Cr and As are predominantly derived from parent materials, and Pb, Hg and Cd are affected by anthropogenic activities. The spatial distribution shows that the Cu, Zn, Ni, Cr, Pb, As and Hg contents of agricultural soils are high in the west and low in the east, and Cd contents are high in the northwest, southeast and low in the southwest in Dongguan. The ratios of vegetable samples which Ni, Pb and As concentrations higher than the Maximum Levels of Contaminants in Foods (GB2762-2005) are 4.7%, 16.3% and 48.8%, respectively. The order of bio-concentration factors (BCF) of heavy metals in vegetables is Cd 〉 Zn 〉 Cu 〉 As 〉 Ni 〉 Hg 〉 Cr 〉 Pb. It is necessary to focus on potential risk of heavy metals for food safety and human's health from agricultural soils and vegetables in Dongguan City, Guangdong Province.展开更多
In recent years,the treatment of agricultural wastewater has been an important aspect of environmental protection.The purpose of photocatalytic technology is to degrade pollutants by utilizing solar light energy to st...In recent years,the treatment of agricultural wastewater has been an important aspect of environmental protection.The purpose of photocatalytic technology is to degrade pollutants by utilizing solar light energy to stimulate the migration of photocarriers to the surface of photocatalysts and occur reduction-oxidation reaction with pollutants in agricultural wastewater.Photocatalytic technology has the characteristics of high efficiency,sustainability,low-energy and free secondary pollution.It is an environmental and economical method to recover water quality that only needs sunlight.In this paper,the mechanism and research progress of photocatalytic removal of heavy metal ions and antibiotics from agricultural water pollution were reviewed by combining photocatalytic degradation process with agricultural treatment technology.The mechanism of influencing factors of photocatalytic degradation efficiency was discussed in detail and corresponding strategies were proposed,which has certain reference value for the development of photocatalytic degradation.展开更多
A detailed investigation was conducted on the relationship between land use patterns and trace metal content in surface soils of the Benue State to assess soil environmental quality. Results revealed that metals level...A detailed investigation was conducted on the relationship between land use patterns and trace metal content in surface soils of the Benue State to assess soil environmental quality. Results revealed that metals levels were generally high in mineralized and urban soils and lower in agricultural soils whilst forest soils were lease by anthropogenic pollution. Mineralized soils developed from weathered sulphides were rich in lead (Pb), zinc (Zn), and cadmium (Cd). Urban soils accumulated copper (Cu), Zn, and Cd most probably from refuse dumps, gasoline combustion and farming. Agricultural soils were enriched in arsenic (As) and to a lesser degree Pb and Cd originating most probably from the application of pesticides, manure and fertilizers. A pollution index (PI) based on plant-tolerant contamination levels, indicates that multi-element contamination in soils is low and implies that the sampled soils could be cultivated for crop production especially away from point sources of pollution. The degree of anthropogenic pollution was high for As (80%), and Pb (54%), moderate for Zn (47%), Cd (40%), and low for Cu (27%). Correlations (r) are significant between Zn- Pb (0.7), Cu-As (0.6) in mineralized soils, between Zn-Cu (0.64), Zn-Cd (0.5), Cu-Cd (0.6), in urban soils, As-Cd (0.61), in agricultural soils and Zn-Pb (0.82) in forest soils. These distinct relationships indicate a common source or similar geochemical control. Based on the overall evaluation, recommendation in respect of contamination, control and monitoring strategies as well as land use planning in the study area are presented.展开更多
Heavy metal pollution in agricultural soils has serious negative influence on human health. Concentrations of Cd, Hg, As, Pb, Cr, Cu, Zn, and Ni in top soils (0-20 cm) of greenhouses and farmlands from four main veg...Heavy metal pollution in agricultural soils has serious negative influence on human health. Concentrations of Cd, Hg, As, Pb, Cr, Cu, Zn, and Ni in top soils (0-20 cm) of greenhouses and farmlands from four main vegetable production areas Shouguang, Laiyang, Jinxiang, and Zhangqiu in Shandong Province, one of the most rapidly developing regions in China, were measured in this study. Shouguang is mainly occupied by greenhouse vegetables and the other three areas are mainly open field culture. Total of 149 soil samples were collected. The average concentrations of the eight heavy metals of the tested 149 soil samples were all below the threshold values according to "Farmland environmental quality evaluation standards for edible agricultural products (HJ332-2006)" of China. However, most of the studied heavy metals were present at higher concentrations than those of the natural background levels in local agricultural soils. Among the total 149 soil samples, 22 samples were contaminated by Cd, Ni, Cu, or Hg. Comparisons showed that the main pollution element in greenhouse vegetable soils was Cd, while that of open field vegetable soils was Cu. The results of principal components analysis (PCA) suggested that concentrations of Cr, As, and Ni were mainly controlled by parent rocks; Hg and Pb were affected by anthropogenic activities such as vehicle and industrial fumes and waste water irrigation. Meanwhile, concentrations of Cd, Cu, and Zn were affected mainly by the use of agrochemicals. Most of the heavy metals were positively correlated with each other in concentration. Appropriate measures should be taken to effectively control heavy metal levels in vegetable soils and thus protect human health.展开更多
Several studies focused on nutrients have shown that land use and management practices have a strong influence on stream chemistry. Much less is known about the relationship between heavy metal concentrations in strea...Several studies focused on nutrients have shown that land use and management practices have a strong influence on stream chemistry. Much less is known about the relationship between heavy metal concentrations in stream water and land use. We compared the variability of trace element concentrations in the stream of a catchment exposed to different types of management practices and land use. This is a small catchment with previous agricultural diffuse and accidental pollution mainly due to the spreading of slurry. The agricultural land was reforested in July 1998. The concentrations of Fe, Mn, Cu and Zn in dissolved phase from surface water samples collected at the catchment outlet were determined over a period of approximately six years. The results suggest that dissolved metal concentrations, especially Cu and Mn, are controlled by the land use and management practices. The median concentrations of studied metals were the highest in the agricultural period. It was also during this period when they all presented the highest concentration peaks, coinciding with a time of heavy application of manure to the soil. Dissolved Fe and Mn showed high dependence of flow rate, whereas Cu and Zn concentrations seemed to be independent of flow.展开更多
The present work is concerned with the voltammetric application of unmodified tricresyl phosphate carbon paste electrode (TCP-CPE) and in situ bismuth-film modified tricresyl phosphate-based carbon paste electrode ...The present work is concerned with the voltammetric application of unmodified tricresyl phosphate carbon paste electrode (TCP-CPE) and in situ bismuth-film modified tricresyl phosphate-based carbon paste electrode (BiF-TCP-CPE). The TCP-CPE was examined with the main objective of using it for the differential pulse voltammetric analysis of some neonicotinoid insecticides in aqueous Britton-Robinson buffer solution pH 7.0 as supporting electrolyte. After comparing the performance of the TCP-CPE with that of silicone oil carbon paste electrode, quantitative analysis of imidacloprid, thiamethoxam and clothianidin was performed in model solutions and real samples (river water and commercial insecticide formulations). The in situ prepared BiF-TCP-CPE was tested for a simultaneous detection of selected heavy metal ions (Cd^2+ and Pb^2+) at a μg/dm^3 concentration level, using square wave anodic stripping voltammetric technique. The influence of different electrochemical pretreatments of the working electrode on the bismuth deposition and analyte signals were investigated. Film formation was studied at untreated, pre-cathodized and pre-anodized TCP-CPEs in the acetic buffer solution pH 4.6, containing 1 μg/cm^3 Bi (III).展开更多
Heavy metal concentrations in agricultural soils of Zhejiang Province were monitored to indicate the status of heavy metal contamination and assess environmental quality of agricultural soils. A total of 908 soil samp...Heavy metal concentrations in agricultural soils of Zhejiang Province were monitored to indicate the status of heavy metal contamination and assess environmental quality of agricultural soils. A total of 908 soil samples were collected from 38 counties in Zbejiang Province and eight heavy metal (Cd, Cr, Pb, Hg, Cu, Zn, Ni and As) concentrations had been evaluated in agricultural soil. It was found 775 samples were unpolluted and 133 samples were slightly polluted and more respectively, that is approximately 14.65% agricultural soil samples had the heavy metal concentration above the threshold level in this province by means of Nemerow's synthetical pollution index method according to the second grade of Standards for Soil Environmental Quality of China (GB15618- 1995). Contamination of Cd was the highest, followed by Ni, As and Zn were lower correspondingly. Moreover, Inverse Distance Weighted (IDW) interpolation method was used to make an assessment map of soil environmental quality based on the Nemerow's pollution index and the soil environmental quality was categorized into five grades. Moreover, ten indices were calculated as input parameters for principal component analysis (PCA) and the principal components (PCs) were created to compare environmental quality of different soils and regions. The results revealed that environmental quality of tea soils was better than that of paddy soils, vegetable soils and fruit soils. This study indicated that GIS combined with multivariate statistical approaches proved to be effective and powerful tool in the mapping of soil contamination distribution and the assessment of soil environmental quality on provincial scale, which is beneficial to environmental protection and management decision-making by local government.展开更多
This paper assesses the agricultural land resources of Guiyang City by means of GIS, on the basis of the pressure-state-response model in which soil heavy metal contamination is selected as a pressure indicator. The r...This paper assesses the agricultural land resources of Guiyang City by means of GIS, on the basis of the pressure-state-response model in which soil heavy metal contamination is selected as a pressure indicator. The results suggest that most of the agricultural land resources are of good quality. However, there are 17.11 km\+2 dry land and paddy field, which belong to the region of serious heavy metal contamination and are not fit for planting crops. At the same time, the high quality plowland, which is suitable for cultivation, has decreased nearly by 1/3 due to soil heavy metal contamination. These findings may improve our understanding that it is very important to prevent and cure heavy metal contamination of Guiyang City.展开更多
Heavy metals in agricultural soil pose human health risks through food consumption. In a novel study for Trinidad, concentration and pollution index levels of heavy metals were assessed from 18 agricultural farms usin...Heavy metals in agricultural soil pose human health risks through food consumption. In a novel study for Trinidad, concentration and pollution index levels of heavy metals were assessed from 18 agricultural farms using the X-Ray fluorescence technique, then to evaluate the Geo-accumulation and Nemerow’s Integrated Pollution indexes. Toxic elements Pb and As were present but soil quality due to anthropogenic input was found as unpolluted. Overall heavy metal pollution was classified at a precautionary level for 33% of farms, slightly polluted for 61% and moderately polluted for 6% of the farms assessed, thus, regular monitoring and mitigation measures are important for food safety and human health in Trinidad.展开更多
Heavy metals(HMs)and antibiotic resistance have become serious environmental problems affecting soil and human health.Soil microorganisms play key roles in pollutant degradation and biogeochemical cycling processes;ho...Heavy metals(HMs)and antibiotic resistance have become serious environmental problems affecting soil and human health.Soil microorganisms play key roles in pollutant degradation and biogeochemical cycling processes;however,the interactions among HMs,soil microbial communities,and antibiotic resistance genes(ARGs)in agricultural soils remain unclear.Using quantitative real-time polymerase chain reaction and NovaSeq sequencing,we evaluated heavy metal contents,abundances of ARGs,soil bacterial community structure and functions,and their correlations in paddy soils at 43 sampling sites along the middle and lower reaches of the Yangtze River,central and eastern China.Our results showed the co-occurrence of HMs,ARGs,and HM resistance genes across all paddy soils.Additionally,significant positive associations were detected between HMs and resistance genes.Cadmium,czcA,and int1 were positively correlated with bacterial community diversity.The Mantel test showed that bacterial community composition and functions were significantly associated with HMs and resistance genes,such as Cd,Cr,Zn,copA,czcA,int1,and sul1.Moreover,HMs and ARGs were the major factors shaping soil bacterial communities;thus,HMs triggered proliferation of HM and antibiotic resistances by influencing the mobile genetic element(int1)and soil microbial communities.Our study revealed that HMs potentially drive the co-selection of ARGs by shifting soil bacterial community structure and functions,thereby increasing the potential risks to human health as well as ecological environment in the paddy soils along the middle and lower reaches of the Yangtze River.展开更多
文摘Heavy metal pollution in agricultural water resources is very serious in re- cent years, resulting in large losses of the agricultural economy and endangering human life and health. Due to the advantages of low cost, high efficiency and less secondary pollution, microbial ramediation technology is widely used in the treatment of heavy metal pollution in agricultural water resources. At present, with the progress of modern biotechnology, microbial remediation of heavy metals in agricul- tural water resources has grown rapidly. The sources and status quo of heavy met- al pollution in agricultural water resources at home and aboard, and the principles of microbial remediation of heavy metals pollution in agricultural water resources were reviewed in this paper, as well as the several common microbial remediation technology of heavy metals in agricultural water resources. Additionally, the further research work of heavy metal contaminated agricultural water resources by microbial ramediation were prospected.
基金Key item of departmental plan of science and technology in Shaanxi Province, No.2003K12-G5 Soft science item of the Ministry of Science and Technology, No.2004DGS3D026 The opening fund of the State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, CAS, No.SKLLQG0515
文摘The monitored soil samples were collected from Heihui irrigated area, Jiaokou irrigated area, Qianhe river valley and Jinghe river valley (hereafter Heihui, Jiaokou, Qianhe and Jinghe for short respectively) of Guanzhong District. According to the Environment Quality Standard for Soil (GB 15618-1995II), we evaluated the pollution status of heavy metals (Cd, As, Cr and Pb) that could seriously endanger soil environment and human health by using single-factor index and synthetic pollution index methods. The results indicate that the synthetic pollution indices P of soil heavy metals are less than 0.7 in Heihui, Jiaokou, Qianhe and Jinghe of Guanzhong, the single-factor indices Pi of soil heavy metals of most soil samples are less than 0.7, so the soil environmental quality is in a good condition in Guanzhong on the whole; the enrichment degree of soil heavy metals is in the order of Heihui, Jinghe, Qianhe and Jiaokou; the contaminated degree of soil heavy metals has the feature of Cd 〉 As 〉 Cr 〉 Pb; heavy metals contents in the cultivated horizon soil are generally higher than those in its underlayer soil, heavy metals contents of soil have the characteristic of enriching towards the cultivated horizon; Cd exceeds standard in the soil samples HS07a, b and HS08a, b at the Yangtao orchard in Heihui and in the soil sample QHS01a at the suburban vegetable plot in Qianhe, which was mainly caused by the long-term irrational use of chemical fertilizer and pesticide.
基金Under the auspices of State Key Development Program for Basic Research of China (No 2002CB410810)
文摘According to the historical changes of coastal lines, seven soil sampling districts, from land to sea, were arranged in Dongtai City, Jiangsu Province to sample soils from surface and profile. Concentrations of seven major heavy metals (HMs), granularity, pH, organic matters and C/N of the soil samples were analyzed. Results show that concentrations of heavy metals in agricultural land present a certain spatial variance, decreasing from land to sea. Pollution assessment indicates that the agricultural soils were not polluted by HMs, but the potential pollution of Cu and Hg needs to be alerted. Different HMs accumulate in the surface and sub-surface of the soil profiles, and concentrations of Hg and Pb decrease significantly with the increment of soil depth. Concentrations of HMs exhibit a significantly negative correlation to pH, but have no significant relation with organic matters in soil. Principle component analysis show that the concentrations of HMs relate to the land use history. Concentrations of Hg, Ni and Cr in soil are closely related with land use history, and concentrations of Pb, Cu and Cr are affected by land use history as well as other factors. However, there is no significant relation between concentration of As and land use history.
基金Supported by Heavy Metal Pollution Mechanism for Water Environment in Xijiang River Basin and Regulation Project(2013GXNSFEA053001)
文摘Using data of 6 pollution-free agricultural product bases in Guangxi Zhuang Autonomous Region,this paper analyzed content of heavy metals,including arsenic(As),mercury(Hg),lead(Pb),cadmium(Cd),and chromium(Cr) in soil.After Pb,Cd,Cr,Hg and As content in soil is determined,it evaluated the pollution of soil using single factor pollution index method and Nemerow synthetic pollution index method in combination with evaluation standard of heavy metals in soil and grading standard for soil pollution.Analysis results indicate that As,Hg,Pb,Cd,Cr content is different in pollution-free agricultural product bases,but all conform to related standards and there is no standard exceeding problem.It is concluded that the quality of soil in pollution-free agricultural product bases is excellent,not polluted and completely meet requirements of evaluation standards,and suitable for developing pollution-free agricultural products.
基金National Natural Science Foundation of China, No.20507022
文摘A total of 219 agricultural soil and 48 vegetable samples were collected from the midstream and downstream of the Xiangjiang River(the Hengyang-Changsha section)in Hunan Province.The accumulation characteristics,spatial distribution and potential risk of heavy metals in the agricultural soils and vegetables were depicted.There are higher accumulations of heavy metals such as As,Cd,Cu,Ni,Pb and Zn in agricultural soils,and the contents of Cd(2.44 mg kg^-1 ),Pb(65.00 mg kg^-1 )and Zn(144.13 mg kg^-1 )are 7.97,3.69 and 1.63 times the corresponding background contents in soils of Hunan Province,respectively. 13.2%of As,68.5%of Cd,2.7%of Cu,2.7%of Ni,8.7%of Pb and 15.1%of Zn in soil samples from the investigated sites exceeded the maximum allowable heavy metal contents in the China Environmental Quality Standard for Soils(GB15618-1995,Grade Ⅱ).The pollution characteristics of multi-metals in soils are mainly due to Cd.The contents of As,Cd,Cu,Pb and Zn in vegetable soils are significantly higher than the contents in paddy soils.95.8%, 68.8%,10.4%and 95.8%of vegetable samples exceeded the Maximum Levels of Contaminants in Foods(GB2762-2005)for As,Cd,Ni and Pb concentrations,respectively.There are significantly positive correlations between the concentrations of Cd,Pb and Zn in vegetables and the concentrations in the corresponding vegetable soils(p〈0.01).It is very necessary to focus on the potential risk of heavy metals for food safety and human health in agricultural soils and vegetables in the midstream and downstream of the Xiangjiang River,Hunan Province of China.
基金Important National Science & Technology Specific Projects of China, No.2007zx07211Fund from the Ministry of Environmental Protection of the People’s Republic of China, No.0202043
文摘A total of 118 of agricultural soil and 43 of vegetable samples were collected from Dongguan City, Guangdong, China. The spatial distribution, sources, accumulation characteristics and potential risk of heavy metals in the agricultural soils and vegetables were depicted in details by three different approaches, including total contents of eight metal elements in soils and vegetables, GIS maps and multivariate analysis of heavy metals in soils in the study. The results show that there are higher accumulation of heavy metals such as Cu, Zn, Ni, Pb, Cd and Hg in agricultural soils, and the contents of Pb (65.38 mg kg^-1) and Hg (0.24 mg kg^-1) are 1.82 and 2.82 times of the background contents of the corresponding heavy metals in soils of Guangdong Province, respectively. There are about 3.4% of Cu, 5.9% of Ni, 1.7% of Cd and 28% of Hg in all collected soil samples from all investigated sites which have overran the contents for heavy metals of the China Environmental Quality Standard for Soils (GB15618-1995, Grade Ⅱ). The pollution characteristics of multi-metals in soils are mainly reflected by Hg. There are different sources to eight metal elements in soils, Cu, Zn, Ni Cr and As are predominantly derived from parent materials, and Pb, Hg and Cd are affected by anthropogenic activities. The spatial distribution shows that the Cu, Zn, Ni, Cr, Pb, As and Hg contents of agricultural soils are high in the west and low in the east, and Cd contents are high in the northwest, southeast and low in the southwest in Dongguan. The ratios of vegetable samples which Ni, Pb and As concentrations higher than the Maximum Levels of Contaminants in Foods (GB2762-2005) are 4.7%, 16.3% and 48.8%, respectively. The order of bio-concentration factors (BCF) of heavy metals in vegetables is Cd 〉 Zn 〉 Cu 〉 As 〉 Ni 〉 Hg 〉 Cr 〉 Pb. It is necessary to focus on potential risk of heavy metals for food safety and human's health from agricultural soils and vegetables in Dongguan City, Guangdong Province.
基金supported by the National Natural Science Foundation of China(52272213)Natural Science Research of Jiangsu Higher Education Institutions of China(21KJB140005)Jiangsu Province and Education Ministry Co-Sponsored Synergistic Innovation Center of Modern Agricultural Equipment(XTCX2024).
文摘In recent years,the treatment of agricultural wastewater has been an important aspect of environmental protection.The purpose of photocatalytic technology is to degrade pollutants by utilizing solar light energy to stimulate the migration of photocarriers to the surface of photocatalysts and occur reduction-oxidation reaction with pollutants in agricultural wastewater.Photocatalytic technology has the characteristics of high efficiency,sustainability,low-energy and free secondary pollution.It is an environmental and economical method to recover water quality that only needs sunlight.In this paper,the mechanism and research progress of photocatalytic removal of heavy metal ions and antibiotics from agricultural water pollution were reviewed by combining photocatalytic degradation process with agricultural treatment technology.The mechanism of influencing factors of photocatalytic degradation efficiency was discussed in detail and corresponding strategies were proposed,which has certain reference value for the development of photocatalytic degradation.
文摘A detailed investigation was conducted on the relationship between land use patterns and trace metal content in surface soils of the Benue State to assess soil environmental quality. Results revealed that metals levels were generally high in mineralized and urban soils and lower in agricultural soils whilst forest soils were lease by anthropogenic pollution. Mineralized soils developed from weathered sulphides were rich in lead (Pb), zinc (Zn), and cadmium (Cd). Urban soils accumulated copper (Cu), Zn, and Cd most probably from refuse dumps, gasoline combustion and farming. Agricultural soils were enriched in arsenic (As) and to a lesser degree Pb and Cd originating most probably from the application of pesticides, manure and fertilizers. A pollution index (PI) based on plant-tolerant contamination levels, indicates that multi-element contamination in soils is low and implies that the sampled soils could be cultivated for crop production especially away from point sources of pollution. The degree of anthropogenic pollution was high for As (80%), and Pb (54%), moderate for Zn (47%), Cd (40%), and low for Cu (27%). Correlations (r) are significant between Zn- Pb (0.7), Cu-As (0.6) in mineralized soils, between Zn-Cu (0.64), Zn-Cd (0.5), Cu-Cd (0.6), in urban soils, As-Cd (0.61), in agricultural soils and Zn-Pb (0.82) in forest soils. These distinct relationships indicate a common source or similar geochemical control. Based on the overall evaluation, recommendation in respect of contamination, control and monitoring strategies as well as land use planning in the study area are presented.
基金supported by the National Key Tech-nology R&D Program of China (2006BAD17B07,2006BDA07A13-1-2) the Staring Fund for Doc-tors of Shandong Academy of Agricultural Sciences,China (2006YBS015)
文摘Heavy metal pollution in agricultural soils has serious negative influence on human health. Concentrations of Cd, Hg, As, Pb, Cr, Cu, Zn, and Ni in top soils (0-20 cm) of greenhouses and farmlands from four main vegetable production areas Shouguang, Laiyang, Jinxiang, and Zhangqiu in Shandong Province, one of the most rapidly developing regions in China, were measured in this study. Shouguang is mainly occupied by greenhouse vegetables and the other three areas are mainly open field culture. Total of 149 soil samples were collected. The average concentrations of the eight heavy metals of the tested 149 soil samples were all below the threshold values according to "Farmland environmental quality evaluation standards for edible agricultural products (HJ332-2006)" of China. However, most of the studied heavy metals were present at higher concentrations than those of the natural background levels in local agricultural soils. Among the total 149 soil samples, 22 samples were contaminated by Cd, Ni, Cu, or Hg. Comparisons showed that the main pollution element in greenhouse vegetable soils was Cd, while that of open field vegetable soils was Cu. The results of principal components analysis (PCA) suggested that concentrations of Cr, As, and Ni were mainly controlled by parent rocks; Hg and Pb were affected by anthropogenic activities such as vehicle and industrial fumes and waste water irrigation. Meanwhile, concentrations of Cd, Cu, and Zn were affected mainly by the use of agrochemicals. Most of the heavy metals were positively correlated with each other in concentration. Appropriate measures should be taken to effectively control heavy metal levels in vegetable soils and thus protect human health.
文摘Several studies focused on nutrients have shown that land use and management practices have a strong influence on stream chemistry. Much less is known about the relationship between heavy metal concentrations in stream water and land use. We compared the variability of trace element concentrations in the stream of a catchment exposed to different types of management practices and land use. This is a small catchment with previous agricultural diffuse and accidental pollution mainly due to the spreading of slurry. The agricultural land was reforested in July 1998. The concentrations of Fe, Mn, Cu and Zn in dissolved phase from surface water samples collected at the catchment outlet were determined over a period of approximately six years. The results suggest that dissolved metal concentrations, especially Cu and Mn, are controlled by the land use and management practices. The median concentrations of studied metals were the highest in the agricultural period. It was also during this period when they all presented the highest concentration peaks, coinciding with a time of heavy application of manure to the soil. Dissolved Fe and Mn showed high dependence of flow rate, whereas Cu and Zn concentrations seemed to be independent of flow.
文摘The present work is concerned with the voltammetric application of unmodified tricresyl phosphate carbon paste electrode (TCP-CPE) and in situ bismuth-film modified tricresyl phosphate-based carbon paste electrode (BiF-TCP-CPE). The TCP-CPE was examined with the main objective of using it for the differential pulse voltammetric analysis of some neonicotinoid insecticides in aqueous Britton-Robinson buffer solution pH 7.0 as supporting electrolyte. After comparing the performance of the TCP-CPE with that of silicone oil carbon paste electrode, quantitative analysis of imidacloprid, thiamethoxam and clothianidin was performed in model solutions and real samples (river water and commercial insecticide formulations). The in situ prepared BiF-TCP-CPE was tested for a simultaneous detection of selected heavy metal ions (Cd^2+ and Pb^2+) at a μg/dm^3 concentration level, using square wave anodic stripping voltammetric technique. The influence of different electrochemical pretreatments of the working electrode on the bismuth deposition and analyte signals were investigated. Film formation was studied at untreated, pre-cathodized and pre-anodized TCP-CPEs in the acetic buffer solution pH 4.6, containing 1 μg/cm^3 Bi (III).
基金Project supported by the National Natural Science Foundation of China (No. 40001008) the Science and Technology Project of Zhejiang Province (No. 2004C32066).
文摘Heavy metal concentrations in agricultural soils of Zhejiang Province were monitored to indicate the status of heavy metal contamination and assess environmental quality of agricultural soils. A total of 908 soil samples were collected from 38 counties in Zbejiang Province and eight heavy metal (Cd, Cr, Pb, Hg, Cu, Zn, Ni and As) concentrations had been evaluated in agricultural soil. It was found 775 samples were unpolluted and 133 samples were slightly polluted and more respectively, that is approximately 14.65% agricultural soil samples had the heavy metal concentration above the threshold level in this province by means of Nemerow's synthetical pollution index method according to the second grade of Standards for Soil Environmental Quality of China (GB15618- 1995). Contamination of Cd was the highest, followed by Ni, As and Zn were lower correspondingly. Moreover, Inverse Distance Weighted (IDW) interpolation method was used to make an assessment map of soil environmental quality based on the Nemerow's pollution index and the soil environmental quality was categorized into five grades. Moreover, ten indices were calculated as input parameters for principal component analysis (PCA) and the principal components (PCs) were created to compare environmental quality of different soils and regions. The results revealed that environmental quality of tea soils was better than that of paddy soils, vegetable soils and fruit soils. This study indicated that GIS combined with multivariate statistical approaches proved to be effective and powerful tool in the mapping of soil contamination distribution and the assessment of soil environmental quality on provincial scale, which is beneficial to environmental protection and management decision-making by local government.
文摘This paper assesses the agricultural land resources of Guiyang City by means of GIS, on the basis of the pressure-state-response model in which soil heavy metal contamination is selected as a pressure indicator. The results suggest that most of the agricultural land resources are of good quality. However, there are 17.11 km\+2 dry land and paddy field, which belong to the region of serious heavy metal contamination and are not fit for planting crops. At the same time, the high quality plowland, which is suitable for cultivation, has decreased nearly by 1/3 due to soil heavy metal contamination. These findings may improve our understanding that it is very important to prevent and cure heavy metal contamination of Guiyang City.
文摘Heavy metals in agricultural soil pose human health risks through food consumption. In a novel study for Trinidad, concentration and pollution index levels of heavy metals were assessed from 18 agricultural farms using the X-Ray fluorescence technique, then to evaluate the Geo-accumulation and Nemerow’s Integrated Pollution indexes. Toxic elements Pb and As were present but soil quality due to anthropogenic input was found as unpolluted. Overall heavy metal pollution was classified at a precautionary level for 33% of farms, slightly polluted for 61% and moderately polluted for 6% of the farms assessed, thus, regular monitoring and mitigation measures are important for food safety and human health in Trinidad.
基金sponsored by the Outstanding Innovative Research Team for Molecular Enzymology and Detection in Anhui Provincial Universities,China(No.2022AH010012)the Program of Anhui Provincial Key Laboratory of the Conservation and Exploitation of Biological Resources,China(No.swzy202001)。
文摘Heavy metals(HMs)and antibiotic resistance have become serious environmental problems affecting soil and human health.Soil microorganisms play key roles in pollutant degradation and biogeochemical cycling processes;however,the interactions among HMs,soil microbial communities,and antibiotic resistance genes(ARGs)in agricultural soils remain unclear.Using quantitative real-time polymerase chain reaction and NovaSeq sequencing,we evaluated heavy metal contents,abundances of ARGs,soil bacterial community structure and functions,and their correlations in paddy soils at 43 sampling sites along the middle and lower reaches of the Yangtze River,central and eastern China.Our results showed the co-occurrence of HMs,ARGs,and HM resistance genes across all paddy soils.Additionally,significant positive associations were detected between HMs and resistance genes.Cadmium,czcA,and int1 were positively correlated with bacterial community diversity.The Mantel test showed that bacterial community composition and functions were significantly associated with HMs and resistance genes,such as Cd,Cr,Zn,copA,czcA,int1,and sul1.Moreover,HMs and ARGs were the major factors shaping soil bacterial communities;thus,HMs triggered proliferation of HM and antibiotic resistances by influencing the mobile genetic element(int1)and soil microbial communities.Our study revealed that HMs potentially drive the co-selection of ARGs by shifting soil bacterial community structure and functions,thereby increasing the potential risks to human health as well as ecological environment in the paddy soils along the middle and lower reaches of the Yangtze River.