[Objectives]To study the characteristics of soil heavy metal contents in facility agriculture of Guangxi and analyze its risks.[Methods]The heavy metal content of 30 surface soil samples taken from facility agricultur...[Objectives]To study the characteristics of soil heavy metal contents in facility agriculture of Guangxi and analyze its risks.[Methods]The heavy metal content of 30 surface soil samples taken from facility agriculture in Guangxi was analyzed.The status of soil heavy metal pollution in facility agriculture of Guangxi was evaluated by the single factor index method,geo-accumulation index method and Hakanson potential ecological risk index method with reference to the soil background value in Guangxi.[Results]Compared with the soil background value in Guangxi,the over-limit rates of heavy metals cadmium,lead,arsenic,chromium,mercury,copper and zinc in soil samples were 56.67%,56.67%,16.67%,30.00%,50.00%,60.00%and 80.00%,respectively.Compared with the screening values of the Soil Environmental Quality-Risk Control Standard for Soil Contamination of Agricultural Land(for trial implementation)(GB15618-2018),the overlimit rates of the heavy metals cadmium,arsenic,copper and zinc in the surface soil of agricultural facilities in Guangxi were 56.67%,10.00%,16.67%and 23.33%,respectively.Except for the average content of soil cadmium exceeding the screening value,the evaluation content of the other six soil heavy metals did not exceed the screening value.According to the evaluation results of the single factor pollution index method,the surface soil arsenic and chromium of the agricultural facilities in Guangxi belonged to the clean level,lead,mercury,and copper belonged to mild pollution,and cadmium and zinc belonged to moderate pollution.According to the evaluation results of the geo-accumulation index,the lead,arsenic,chromium and mercury in the surface soil of the agricultural facilities in Guangxi belonged to the pollution-free level,while the cadmium,copper and zinc belonged to the mild-moderate pollution.According to the evaluation results of the potential ecological risk index method,the potential ecological risks of the heavy metals of lead,arsenic,chromium,copper and zinc in the soil of agricultural facilities in Guangxi belonged to low potential ecological risk level,and the potential ecological risks of cadmium and mercury belonged to moderate risk level.The potential ecological risk index(RI)of the seven heavy metals in the soil was 132.46,which belonged to moderate potential ecological risk.The largest contribution of soil heavy metals to the potential ecological risk index was cadmium and mercury.[Conclusions]Taking the soil of facility agriculture in Guangxi as the object,this paper studied the characteristics of heavy metal content in facility agricultural soil and its risk assessment,in order to provide a scientific basis for facility soil heavy metal risk prevention and control and provide safe technology for facility agriculture.展开更多
According to the previous literature published since 1989,statistical analysis for reported data on the heavy metals in Chinese vegetable plantation soils was carried out systematically in this article. The purpose of...According to the previous literature published since 1989,statistical analysis for reported data on the heavy metals in Chinese vegetable plantation soils was carried out systematically in this article. The purpose of this investigation was to study the status of heavy metal content in vegetable land soils systematically through objective assessment to promote the development of vegetable production with high quality and efficiency. It is concluded that Zn,Cr,Cu had relatively high concentrations while the mean concentrations of toxic metals,As,Hg,Cd were 8.03,0.12,0.28 mg kg-1,respectively with comparatively low concentrations in Chinese vegetable land. Comparing to Chinese Soil Quality Criterion GB 15618-1995 (6.5 < pH < 7.5),about 24.1,10.3,and 9.2% of the total samples was contaminated by Cd,Hg,and As,respectively,and the descending order of heavy metals was Cd > Hg > As > Zn > Cu > Cr > Pb. When compared among different regions,the more serious heavy metal contamination was found in the vegetable land of eastern China and the main contamination elements were Cd,Hg,and Zn. In the mid region,vegetable plantation land soil was mainly polluted by As and Cd,as well as by Hg,Zn,and Cu,to some extent. In the west region of China,Cd and As contamination was also observed to some degree,along with few soil samples exceeding the grade II level of GB 15618-1995 (6.5 < pH < 7.5) for Cu,Cr,and Hg content. Compared to the five vegetable plantation land patterns,the highest concentration of As,Cd,Hg,and Zn occurred in the industrial/sewage irrigation vegetable land,especially for Hg with 2.36 mg kg-1 content averagely,which is 10.5-21.1 times higher than the other four types of vegetable lands. The highest concentration of Cu and Cr occurred in the greenhouse vegetable land soils,and urban vegetable land soil had the highest Pb content in comparison with the other types of vegetable plantation land patterns. By analyzing heavy metal content under different vegetable land patterns,it was found that soil in vegetable production base had relatively low heavy metal concentrations except for Pb with a slightly higher amount in the suburb area. The soil quality of common vegetable land was good with the lowest concentrations for most heavy metals. Under present utilization patterns of vegetable land,the soil quality in Chinese vegetable base land was good with comparatively low concentrations of heavy metals and mostly not exceeding the grade II level of Chinese Soil Quality Criterion GB 15618-1995 (6.5 < pH < 7.5). However,comparatively serious contamination was found in industrial/sewage irrigation and suburb vegetable land soils.展开更多
The effect of crude oil pollution on heavy metal content in the soil, microbial population, and growth performance of maize and cowpea was investigated. The heavy metals determined were lead, cadmium, iron, nickel, zi...The effect of crude oil pollution on heavy metal content in the soil, microbial population, and growth performance of maize and cowpea was investigated. The heavy metals determined were lead, cadmium, iron, nickel, zinc and copper. Microbial population and growth performance of maize and cowpea in both polluted and unpolluted soils samples were evaluated. Results showed that higher concentration of heavy metals was observed in all crops planted in polluted soil, polluted site vegetation and soils. The total heterotrophic bacteria was 89% lower in the polluted soil than in the unpolluted soil while fungi was 78% lower in the polluted soil when compared to the unpolluted soil. However, hydrocarbon utilizing bacteria and fungi was 22% and 24% higher in the polluted soil than in the unpolluted soil respectively. Maize and Cowpea performed poorly in polluted soil when compared with unpolluted soil as evidenced in the growth parameters measured for both crops.展开更多
Excessive use of agro-chemicals(such as mineral fertilizers) poses potential risks to soil quality. Application of organic amendments and reduction of inorganic fertilizer are economically feasible and environmentally...Excessive use of agro-chemicals(such as mineral fertilizers) poses potential risks to soil quality. Application of organic amendments and reduction of inorganic fertilizer are economically feasible and environmentally sound approaches to develop sustainable agriculture. This study investigated and evaluated the effects of mineral fertilizer reduction and partial substitution of organic amendment on soil fertility and heavy metal content in a 10-season continually planted vegetable field during 2009–2012. The experiment included four treatments: 100% chemical fertilizer(CF100), 80% chemical fertilizer(CF80), 60% chemical fertilizer and 20% organic fertilizer(CF60+OM20), and 40% chemical fertilizer and 40% organic fertilizer(CF40+OM40). Soil nutrients, enzyme activity and heavy metal content were determined. The results showed that single chemical fertilizer reduction(CF80) had no significant effect on soil organic matter content, soil catalase activity and soil heavy metal content, but slightly reduced soil available N, P, K, and soil urease activity, and significantly reduced soil acid phosphatase activity. Compared with CF100, 40 or 60% reduction of chemical fertilizer supplemented with organic fertilizer(CF60+OM20, CF40+OM40) significantly increased soil organic matter, soil catalase activity and urease activity especially in last several seasons, but reduced soil available P, K, and soil acid phosphatase activity. In addition, continuous application of organic fertilizer resulted in higher accumulation of Zn, Cd, and Cr in soil in the late stage of experiment, which may induce adverse effects on soil health and food safety.展开更多
Measurements of the magnetic properties and total contents of Cu, Cd, Pb and Fe in 30 automobile emission par-ticulate samples indicated the presence of magnetic particles in them. The values of frequency dependent su...Measurements of the magnetic properties and total contents of Cu, Cd, Pb and Fe in 30 automobile emission par-ticulate samples indicated the presence of magnetic particles in them. The values of frequency dependent susceptibility (χfd) showed the absence of superparamagnetic (SP) grains in the samples. The IRM20 mT (isothermal remanent magnetization at 20 mT) being linearly proportional to SIRM (saturation isothermal remanent magnetization) (R2=0.901), suggested that ferrimagnetic minerals were responsible for the magnetic properties of automobile emission particulates. The average contents of Cu, Cd, Pb and Fe in automobile emission particulates were 95.83, 22.14, 30.58 and 34727.31 mg/kg, respectively. Significant positive correla-tions exist between the magnetic parameters and the contents of Pb, Cu and Fe. The magnetic parameters of automobile emission particulates reflecting concentration of magnetic particles increased linearly with increase of Pb and Cu content, showed that the magnetic measurement could be used as a preliminary index for detection of Pb and Cu pollution.展开更多
To understand heavy metal content in soil of rural landfill in Chongqing,samples were collected at 10 sampling sites of different counties.Zn,Cr,Cu,Cd and Pb contents were analyzed,and their pollution degrees were eva...To understand heavy metal content in soil of rural landfill in Chongqing,samples were collected at 10 sampling sites of different counties.Zn,Cr,Cu,Cd and Pb contents were analyzed,and their pollution degrees were evaluated by single-factor evaluation and index of geoaccumulation. Results displayed that there was no Cr pollution in soil of rural landfill in Chongqing,but Cd pollution was very serious. Pb,Zn and Cu showed spatial difference in different counties. Dispersion degrees of Zn and Pb pollution were lower,and their pollution degrees were also relatively lower.Dispersion degree of Cu pollution was higher,and its pollution degree was also relatively higher.展开更多
Pb, Cd and As are main heavy metal elements in tobacco leaves in China. Through the application of organic fertilizers in the tobacco area of Pu'er City, the effects on tobacco growth and heavy metal contents were...Pb, Cd and As are main heavy metal elements in tobacco leaves in China. Through the application of organic fertilizers in the tobacco area of Pu'er City, the effects on tobacco growth and heavy metal contents were investigated. The results showed that the tobacco plants in the treatments applied with organic fertilizers as the base fertilizer grew at a lower rate and had relatively smaller stem girth and leaf number than the treatment applied with the compound fertilizer special for tobacco in early growth period, and the differences between various treatments were not significant. After applying the organic fertilizers, they had a positive effect in reducing heavy metal contents of flue-cured tobacco, and the effect of applying oil cake was better, followed by the treatment of chicken manure plus oil cake. The sole application of chicken manure had a certain effect on the control of Hg, As and Pb, but the Cd content increased. For the areas with high heavy metal levels, the selection of appropriate organic fertilizers has a practical significance to the reduction of heavy metal contents in tobacco leaves.展开更多
Turkey’s inland water ecosystem consists of 33 rivers (177.714 miles), 200 natural lakes (906.118 ha), 159 reservoirs (342.377 ha) and 750 ponds (15.500 ha). Sedimentological studies conducted on inland water ecosyst...Turkey’s inland water ecosystem consists of 33 rivers (177.714 miles), 200 natural lakes (906.118 ha), 159 reservoirs (342.377 ha) and 750 ponds (15.500 ha). Sedimentological studies conducted on inland water ecosystems during the last 15 years in Turkey can be categorized into two main topics. The first group of studies is concerned with heavy metal levels in sediment, with especial reference to the interaction between water, sediment and aquatic organisms. Additionally, the studies in question deal with the potential impacts of heavy metal concentrations on the ecosystem. The second group of studies is concerned with the role of eutrophication in the sediment as a result of serious contamination of inland water ecosystems. It is known that the sediment can directly influence the nutrient level in standing inland waters such as lakes and ponds by way of internal nutrient loading. In this context, studies regarding sediment, overlying water, sediment pore water and nutrient release from the sediment should be emphasized as these are important steps with respect to the eutrophication process. By keeping these studies in mind, the researcher in this study compiled and analyzed studies dealing with inland water ecosystems with differing nutrient levels and uses, including for drinking water, in Turkey’s drainage basins. In addition, field and laboratory studies regarding nutrient release from sediment into Turkey’s inland water ecosystems were evaluated in light of lake management practices.展开更多
Heavy metals not only adversely affect the quality of tobacco leaves,but also have very adverse effects on human health. In order to find out the effective cultivation method of controlling heavy metal content in flue...Heavy metals not only adversely affect the quality of tobacco leaves,but also have very adverse effects on human health. In order to find out the effective cultivation method of controlling heavy metal content in flue-cured tobacco,the content of four kinds of heavy metals in soil and tobacco leaves in different intercropping treatments was tested. The results showed that there were significant differences between the effects of intercropping on the content of some heavy metals in soil and tobacco leaves. Different interplanting methods had a positive effect on the reduction of heavy metal content in tobacco leaves and play a very important and positive role in actual production.展开更多
Taking three mains edibles products(walnut, prickly ash and bamboo shoots) and origin soil in central area of Sichuan Province as the study objects, this research aimed at revealing the level of heavy metals and pesti...Taking three mains edibles products(walnut, prickly ash and bamboo shoots) and origin soil in central area of Sichuan Province as the study objects, this research aimed at revealing the level of heavy metals and pesticide residue and comprehensive evaluation the soil heavy metal pollution in the region. The results showed that: ① Soil organic matter, total nitrogen, total phosphorus and heavy metal contents of mercury, arsenic in the south area were significant higher than that in the north area, while the heavy metal contents of lead and copper were significantly higher in the north area; ② The pollution index of six heavy metals of cadmium, mercury, arsenic, lead, chromium and copper in the producing area was less than 1.0. However, the integrated pollution index was at a warning level, and there was a potential risk of cadmium contamination; ③ The walnut samples exceeded the lead limit value over 75% in the north area and over 35% in the south area, and the same as 30% of bamboo shoot samples; ④ There was a significant negative correlation of mercury content between walnut samples and production soil, and a significant positive correlation of arsenic content between bamboo shoots and production soil. In addition, there is no significant correlation of heavy metal contents between prickly samples and production soil; ⑤ Fenthion residues were detected in walnuts, malathion samples were detected in prickly ash, and chlorothalonil, dimethoate and chlorpyrifos residues in bamboo shoots samples. None of theses pesticide residues exceeded the standard limit value. In general, the soil is in well sanitary condition and the edible forest products are not exposed to the contamination of pesticide residues in the study area. The quality and safety of the prickly ash is good while the walnut and bamboo shoots have certain risks in terms of high lead level.展开更多
Concentrations of lead( Pb),cadmium( Cd),chromium( Cr),copper( Cu),zinc( Zn) and manganese( Mn) were measured in various organs( such as in liver and muscle) from 9 species of freshwater economic fishes which were col...Concentrations of lead( Pb),cadmium( Cd),chromium( Cr),copper( Cu),zinc( Zn) and manganese( Mn) were measured in various organs( such as in liver and muscle) from 9 species of freshwater economic fishes which were collected from northeast area of Guangdong Province. The concentration of metals was measured by inductively coupled plasma atomic emission spectrometry( ICP- AES). Results showed that the levels of metals in hepatopancreas of the fishes were found in order of Zn > Pb > Cu > Hg > Cd,while in muscles were Zn > Cr> Pb > Mn > Cu > Cd. In general,the metals concentrations were significantly higher in liver samples than that in muscle samples. Based on the " pollution index of single factor",the fishes,to one degree or another,were polluted by Pb,Cd,Cr,Cu and Zn,and pollution levels were mostly followed by Pb > Cd > Cr > Cu > Zn. The indexes of Pb and Cd tested in hepatopancreas of the fishes were in a majority exceeded the national safety criteria for food in China. What's more,it was found that the contents of the heavy metals in fishes did not vary with the trophic level which they belong to. In summary,the fishes were polluted by Pb,Cd,Cr,Cu and Zn to some extent,which indicated that hidden danger of heavy metals pollution was present in ecological environment or safety in fishery production in the area.展开更多
[Objectives]This study aimed to explore the effect of different concentrations of selenium fertilizer on the yield,selenium content and heavy metal contents of waxy maize,thereby providing reference for the scientific...[Objectives]This study aimed to explore the effect of different concentrations of selenium fertilizer on the yield,selenium content and heavy metal contents of waxy maize,thereby providing reference for the scientific application of selenium fertilizer on waxy maize.[Methods]Different varieties of waxy maize(Guitiannuo 611,Guinuo 615 and Guiheinuo 609)were used as test materials.They were sprayed with different concentrations(0,0.5,1.0,1.5 and 2.0 g/L)of water-soluble selenium fertilizer(Xinxibao)at the big flare stage,and the effect on the yield,selenium content and heavy metal contents of the waxy maize was analyzed.[Results]Foliar application of different concentrations of selenium fertilizer showed no significant effect on the yield and yield components of waxy maize.As the concentration of selenium fertilizer increased,the grain selenium content of different varieties of waxy maize increased.Among them,the increase of Guinuo 615 was the largest,of which the selenium content reached 0.265 mg/kg,2.82 times that of the control(water).The cadmium and arsenic contents of different varieties of waxy maize decreased with the increase of the concentration of selenium fertilizer sprayed.Among the waxy maize varieties,the cadmium and arsenic contents of Guitiannuo 611 dropped the most significantly,up to 52.94%and 77.78%.In waxy maize,the correlation coefficients between selenium content and cadmium,arsenic contents were-0.5509(P<0.05)and-0.8530(P<0.01),respectively.[Conclusions]Spraying exogenous selenium fertilizer had no obvious effect on the yield of waxy maize.However,the increase of the concentration of exogenous selenium fertilizer could significantly increase the selenium content and reduce the cadmium and arsenic contents in grains of different varieties of waxy maize.展开更多
In order to determine and assess the concentrations of trace elements in coral reefs sediments from Red Sea of Yemen,sediment samples were collected,treated and analyzed for cadmium,chromium,cobalt,copper,manganese,ni...In order to determine and assess the concentrations of trace elements in coral reefs sediments from Red Sea of Yemen,sediment samples were collected,treated and analyzed for cadmium,chromium,cobalt,copper,manganese,nickel,iead,iron,zinc and vanadium by the atomic absorption spectrometric analysis.The result is that cadmium,cobalt and lead concentrations were high and other elements are low or the same as natural background.It is concluded that the high cadmium,cobalt and lead levels in coral reefs sediments will have negative effects on marine life of the sites,so further researches are needed to characterize the sources fate,biogeochemical processes and impacts of these trace elements on coral reefs and marine of the region.展开更多
Spices are generally consumed because of their medicinal properties, taste, and add flavor to food. Objectives: To determine the nutrient contents and heavy metals of five commonly consumed spices, namely turmeric (Cu...Spices are generally consumed because of their medicinal properties, taste, and add flavor to food. Objectives: To determine the nutrient contents and heavy metals of five commonly consumed spices, namely turmeric (Curcuma longa), bay leaf (Laurus nobilis), red chili (Capsicum annuum), coriander (Coriander sativum), and black cumin (Nigella sativa) were collected from the local market of Northern zone, Bangladesh and were analyzed. Methods: Nutrient composition was assessed by proximate analysis, trace and heavy metals by atomic absorption spectrophotometry while the indophenol method was used to determine vitamin C. Result: The results revealed that spices are good sources of carbohydrate, fiber, and fat. The highest levels of carbohydrates, dietary fiber, protein, and fat were observed in turmeric (71.1%), black cumin (40.0%), red chili (16.77%), and coriander (17.8%) respectively. Vitamin C was present in trace amounts ranging from 0.04 to 0.1 mg/100g, except black cumin (35.0 mg/100g). Essential trace minerals like sodium, potassium, calcium, magnesium, and iron were significantly present in black cumin and bay leaf. Most of the heavy metal levels in the spices were appreciable amounts i.e. much lesser than the statutory safe limit approved by WHO and FAO for some of the samples. Conclusion: The current study concluded that the investigated spices are nutritionally rich, and heavy metal levels in the examined samples are safe for human consumption.展开更多
In order to explore the application effect of the comprehensive control technology of"soil conditioning-organic planting-foliar control"in the rice area of northern Guangdong,the effects of combined applicat...In order to explore the application effect of the comprehensive control technology of"soil conditioning-organic planting-foliar control"in the rice area of northern Guangdong,the effects of combined application of different dosages of soil conditioner,bio-organic fertilizer and foliar control agent on heavy metal contents and yields of early and late rice were investigated based on field experiments.The results showed that different treatments of early rice and late rice all increased the yield.The yield increase rates of treatments 2,3 and 4 reached 4.9%,7.2%and 8.7%in early rice,respectively,and those in late rice reached 7.7%,7.8%and 9.7%,respectively.And the cadmium contents of early rice and late rice in treatments 2,3 and 4 were significantly reduced below the safe value.Taking into account factors such as cost,yield increase rate,and heavy metal compliance rate,the recommended application rate for early and late rice is conventional fertilization+soil conditioner 6000 kg/hm^(2)+bio-organic fertilizer 1800 kg/hm^(2)+foliar control agent 6000 ml/hm^(2).展开更多
A study was conducted to assess the heavy metal (As, Pb, Cd, Cr, Cu, Zn and Hg) contents of different sources of wastes generated in Dhaka city which was further used for a compost plant. The study consisted of both f...A study was conducted to assess the heavy metal (As, Pb, Cd, Cr, Cu, Zn and Hg) contents of different sources of wastes generated in Dhaka city which was further used for a compost plant. The study consisted of both field survey and laboratory analyses. Relevant primary and secondary sources of data were collected to identify the source and nature of wastes generated near the compost plant. A total of eight households, ten officers and ten waste collectors were surveyed for data collection. For laboratory analyses, wastes from various socio-economic niches (lower, lower middle, middle and high) were collected. The result showed that wastes generated in the lower income niche contained the minimum contents of heavy metals compared to middle and high niches. The increasing trend of heavy metal contents of the wastes from lower to high income groups has been found to be linked to the life style, attitude, profession, culture and food habit. Most of the heavy metals did not meet the standard level for almost all the niches. Most of the correlations were found to be insignificant between the contents of nutrient element (C, N and P) and heavy metals (As, Pb, Cd, Cr, Cu, Zn and Hg).展开更多
基金Supported by Key Research and Development Program of Guangxi(Gui Ke AB18221096)Fund of Guangxi Academy of Agricultural Sciences(2019ZX121Gui Nong Ke 2020ZX03)
文摘[Objectives]To study the characteristics of soil heavy metal contents in facility agriculture of Guangxi and analyze its risks.[Methods]The heavy metal content of 30 surface soil samples taken from facility agriculture in Guangxi was analyzed.The status of soil heavy metal pollution in facility agriculture of Guangxi was evaluated by the single factor index method,geo-accumulation index method and Hakanson potential ecological risk index method with reference to the soil background value in Guangxi.[Results]Compared with the soil background value in Guangxi,the over-limit rates of heavy metals cadmium,lead,arsenic,chromium,mercury,copper and zinc in soil samples were 56.67%,56.67%,16.67%,30.00%,50.00%,60.00%and 80.00%,respectively.Compared with the screening values of the Soil Environmental Quality-Risk Control Standard for Soil Contamination of Agricultural Land(for trial implementation)(GB15618-2018),the overlimit rates of the heavy metals cadmium,arsenic,copper and zinc in the surface soil of agricultural facilities in Guangxi were 56.67%,10.00%,16.67%and 23.33%,respectively.Except for the average content of soil cadmium exceeding the screening value,the evaluation content of the other six soil heavy metals did not exceed the screening value.According to the evaluation results of the single factor pollution index method,the surface soil arsenic and chromium of the agricultural facilities in Guangxi belonged to the clean level,lead,mercury,and copper belonged to mild pollution,and cadmium and zinc belonged to moderate pollution.According to the evaluation results of the geo-accumulation index,the lead,arsenic,chromium and mercury in the surface soil of the agricultural facilities in Guangxi belonged to the pollution-free level,while the cadmium,copper and zinc belonged to the mild-moderate pollution.According to the evaluation results of the potential ecological risk index method,the potential ecological risks of the heavy metals of lead,arsenic,chromium,copper and zinc in the soil of agricultural facilities in Guangxi belonged to low potential ecological risk level,and the potential ecological risks of cadmium and mercury belonged to moderate risk level.The potential ecological risk index(RI)of the seven heavy metals in the soil was 132.46,which belonged to moderate potential ecological risk.The largest contribution of soil heavy metals to the potential ecological risk index was cadmium and mercury.[Conclusions]Taking the soil of facility agriculture in Guangxi as the object,this paper studied the characteristics of heavy metal content in facility agricultural soil and its risk assessment,in order to provide a scientific basis for facility soil heavy metal risk prevention and control and provide safe technology for facility agriculture.
基金the National Key Technology R&D Program during the 11th Five-Year Plan period (2006BAD05B01)the project of Standards on Heavy Metal Contamination of Farmlands (2007-2009)Special Public Welfare Fund of Basic Scientific Research Service Spends for Research Institute/Academy supported by China Central Government
文摘According to the previous literature published since 1989,statistical analysis for reported data on the heavy metals in Chinese vegetable plantation soils was carried out systematically in this article. The purpose of this investigation was to study the status of heavy metal content in vegetable land soils systematically through objective assessment to promote the development of vegetable production with high quality and efficiency. It is concluded that Zn,Cr,Cu had relatively high concentrations while the mean concentrations of toxic metals,As,Hg,Cd were 8.03,0.12,0.28 mg kg-1,respectively with comparatively low concentrations in Chinese vegetable land. Comparing to Chinese Soil Quality Criterion GB 15618-1995 (6.5 < pH < 7.5),about 24.1,10.3,and 9.2% of the total samples was contaminated by Cd,Hg,and As,respectively,and the descending order of heavy metals was Cd > Hg > As > Zn > Cu > Cr > Pb. When compared among different regions,the more serious heavy metal contamination was found in the vegetable land of eastern China and the main contamination elements were Cd,Hg,and Zn. In the mid region,vegetable plantation land soil was mainly polluted by As and Cd,as well as by Hg,Zn,and Cu,to some extent. In the west region of China,Cd and As contamination was also observed to some degree,along with few soil samples exceeding the grade II level of GB 15618-1995 (6.5 < pH < 7.5) for Cu,Cr,and Hg content. Compared to the five vegetable plantation land patterns,the highest concentration of As,Cd,Hg,and Zn occurred in the industrial/sewage irrigation vegetable land,especially for Hg with 2.36 mg kg-1 content averagely,which is 10.5-21.1 times higher than the other four types of vegetable lands. The highest concentration of Cu and Cr occurred in the greenhouse vegetable land soils,and urban vegetable land soil had the highest Pb content in comparison with the other types of vegetable plantation land patterns. By analyzing heavy metal content under different vegetable land patterns,it was found that soil in vegetable production base had relatively low heavy metal concentrations except for Pb with a slightly higher amount in the suburb area. The soil quality of common vegetable land was good with the lowest concentrations for most heavy metals. Under present utilization patterns of vegetable land,the soil quality in Chinese vegetable base land was good with comparatively low concentrations of heavy metals and mostly not exceeding the grade II level of Chinese Soil Quality Criterion GB 15618-1995 (6.5 < pH < 7.5). However,comparatively serious contamination was found in industrial/sewage irrigation and suburb vegetable land soils.
文摘The effect of crude oil pollution on heavy metal content in the soil, microbial population, and growth performance of maize and cowpea was investigated. The heavy metals determined were lead, cadmium, iron, nickel, zinc and copper. Microbial population and growth performance of maize and cowpea in both polluted and unpolluted soils samples were evaluated. Results showed that higher concentration of heavy metals was observed in all crops planted in polluted soil, polluted site vegetation and soils. The total heterotrophic bacteria was 89% lower in the polluted soil than in the unpolluted soil while fungi was 78% lower in the polluted soil when compared to the unpolluted soil. However, hydrocarbon utilizing bacteria and fungi was 22% and 24% higher in the polluted soil than in the unpolluted soil respectively. Maize and Cowpea performed poorly in polluted soil when compared with unpolluted soil as evidenced in the growth parameters measured for both crops.
基金financially supported by grants of the Key Projects in the Key Technologies R&D Program of China during the 12th Five-Year Plan period(2012BAD14B00)the Guangdong Provincial Science and Technology Plan Key Project,China(2012A020100003,2015A050502043)
文摘Excessive use of agro-chemicals(such as mineral fertilizers) poses potential risks to soil quality. Application of organic amendments and reduction of inorganic fertilizer are economically feasible and environmentally sound approaches to develop sustainable agriculture. This study investigated and evaluated the effects of mineral fertilizer reduction and partial substitution of organic amendment on soil fertility and heavy metal content in a 10-season continually planted vegetable field during 2009–2012. The experiment included four treatments: 100% chemical fertilizer(CF100), 80% chemical fertilizer(CF80), 60% chemical fertilizer and 20% organic fertilizer(CF60+OM20), and 40% chemical fertilizer and 40% organic fertilizer(CF40+OM40). Soil nutrients, enzyme activity and heavy metal content were determined. The results showed that single chemical fertilizer reduction(CF80) had no significant effect on soil organic matter content, soil catalase activity and soil heavy metal content, but slightly reduced soil available N, P, K, and soil urease activity, and significantly reduced soil acid phosphatase activity. Compared with CF100, 40 or 60% reduction of chemical fertilizer supplemented with organic fertilizer(CF60+OM20, CF40+OM40) significantly increased soil organic matter, soil catalase activity and urease activity especially in last several seasons, but reduced soil available P, K, and soil acid phosphatase activity. In addition, continuous application of organic fertilizer resulted in higher accumulation of Zn, Cd, and Cr in soil in the late stage of experiment, which may induce adverse effects on soil health and food safety.
基金Project supported by the National Natural Science Foundation of China (No. 40371056)the Foundation for the Author of NationalExcellent Doctoral Dissertation of China (No. 200149)
文摘Measurements of the magnetic properties and total contents of Cu, Cd, Pb and Fe in 30 automobile emission par-ticulate samples indicated the presence of magnetic particles in them. The values of frequency dependent susceptibility (χfd) showed the absence of superparamagnetic (SP) grains in the samples. The IRM20 mT (isothermal remanent magnetization at 20 mT) being linearly proportional to SIRM (saturation isothermal remanent magnetization) (R2=0.901), suggested that ferrimagnetic minerals were responsible for the magnetic properties of automobile emission particulates. The average contents of Cu, Cd, Pb and Fe in automobile emission particulates were 95.83, 22.14, 30.58 and 34727.31 mg/kg, respectively. Significant positive correla-tions exist between the magnetic parameters and the contents of Pb, Cu and Fe. The magnetic parameters of automobile emission particulates reflecting concentration of magnetic particles increased linearly with increase of Pb and Cu content, showed that the magnetic measurement could be used as a preliminary index for detection of Pb and Cu pollution.
基金Supported by Municipal Key Laboratory Project of Chongqing HigherSchool,China(WEPKL2013QN-02)Municipal Innovation and Entre-preneurship Training Program of University Student in Chongqing in2013,China(201310643003)
文摘To understand heavy metal content in soil of rural landfill in Chongqing,samples were collected at 10 sampling sites of different counties.Zn,Cr,Cu,Cd and Pb contents were analyzed,and their pollution degrees were evaluated by single-factor evaluation and index of geoaccumulation. Results displayed that there was no Cr pollution in soil of rural landfill in Chongqing,but Cd pollution was very serious. Pb,Zn and Cu showed spatial difference in different counties. Dispersion degrees of Zn and Pb pollution were lower,and their pollution degrees were also relatively lower.Dispersion degree of Cu pollution was higher,and its pollution degree was also relatively higher.
基金Supported by Hongyun Honghe Tobacco(Group)Science and Technology Project(HYHH2013YL01)Tea Science Discipline Practical Training Base Construction Project of Institute of Agricultural and Garden Technology,Pu'er University
文摘Pb, Cd and As are main heavy metal elements in tobacco leaves in China. Through the application of organic fertilizers in the tobacco area of Pu'er City, the effects on tobacco growth and heavy metal contents were investigated. The results showed that the tobacco plants in the treatments applied with organic fertilizers as the base fertilizer grew at a lower rate and had relatively smaller stem girth and leaf number than the treatment applied with the compound fertilizer special for tobacco in early growth period, and the differences between various treatments were not significant. After applying the organic fertilizers, they had a positive effect in reducing heavy metal contents of flue-cured tobacco, and the effect of applying oil cake was better, followed by the treatment of chicken manure plus oil cake. The sole application of chicken manure had a certain effect on the control of Hg, As and Pb, but the Cd content increased. For the areas with high heavy metal levels, the selection of appropriate organic fertilizers has a practical significance to the reduction of heavy metal contents in tobacco leaves.
文摘Turkey’s inland water ecosystem consists of 33 rivers (177.714 miles), 200 natural lakes (906.118 ha), 159 reservoirs (342.377 ha) and 750 ponds (15.500 ha). Sedimentological studies conducted on inland water ecosystems during the last 15 years in Turkey can be categorized into two main topics. The first group of studies is concerned with heavy metal levels in sediment, with especial reference to the interaction between water, sediment and aquatic organisms. Additionally, the studies in question deal with the potential impacts of heavy metal concentrations on the ecosystem. The second group of studies is concerned with the role of eutrophication in the sediment as a result of serious contamination of inland water ecosystems. It is known that the sediment can directly influence the nutrient level in standing inland waters such as lakes and ponds by way of internal nutrient loading. In this context, studies regarding sediment, overlying water, sediment pore water and nutrient release from the sediment should be emphasized as these are important steps with respect to the eutrophication process. By keeping these studies in mind, the researcher in this study compiled and analyzed studies dealing with inland water ecosystems with differing nutrient levels and uses, including for drinking water, in Turkey’s drainage basins. In addition, field and laboratory studies regarding nutrient release from sediment into Turkey’s inland water ecosystems were evaluated in light of lake management practices.
基金Supported by Science and Technology Project of Hongyun Honghe Tobacco(Group)Co.,Ltd.(HYHH2013YL01)Tea Science Specialty Practice and Training Base Construction Project of College of Agriculture and Forestry,Pu'er University
文摘Heavy metals not only adversely affect the quality of tobacco leaves,but also have very adverse effects on human health. In order to find out the effective cultivation method of controlling heavy metal content in flue-cured tobacco,the content of four kinds of heavy metals in soil and tobacco leaves in different intercropping treatments was tested. The results showed that there were significant differences between the effects of intercropping on the content of some heavy metals in soil and tobacco leaves. Different interplanting methods had a positive effect on the reduction of heavy metal content in tobacco leaves and play a very important and positive role in actual production.
基金Supported by the Guizhou Provincial Education Department of Education's Youth Science and Technology Project Fund Grant No.161/2016(Q-J-H-KY)the Science and Technology Planning Project of Guizhou Science and Technology Department Project Fund grant No.1074/2018(Qian-ke-he-basic)
文摘Taking three mains edibles products(walnut, prickly ash and bamboo shoots) and origin soil in central area of Sichuan Province as the study objects, this research aimed at revealing the level of heavy metals and pesticide residue and comprehensive evaluation the soil heavy metal pollution in the region. The results showed that: ① Soil organic matter, total nitrogen, total phosphorus and heavy metal contents of mercury, arsenic in the south area were significant higher than that in the north area, while the heavy metal contents of lead and copper were significantly higher in the north area; ② The pollution index of six heavy metals of cadmium, mercury, arsenic, lead, chromium and copper in the producing area was less than 1.0. However, the integrated pollution index was at a warning level, and there was a potential risk of cadmium contamination; ③ The walnut samples exceeded the lead limit value over 75% in the north area and over 35% in the south area, and the same as 30% of bamboo shoot samples; ④ There was a significant negative correlation of mercury content between walnut samples and production soil, and a significant positive correlation of arsenic content between bamboo shoots and production soil. In addition, there is no significant correlation of heavy metal contents between prickly samples and production soil; ⑤ Fenthion residues were detected in walnuts, malathion samples were detected in prickly ash, and chlorothalonil, dimethoate and chlorpyrifos residues in bamboo shoots samples. None of theses pesticide residues exceeded the standard limit value. In general, the soil is in well sanitary condition and the edible forest products are not exposed to the contamination of pesticide residues in the study area. The quality and safety of the prickly ash is good while the walnut and bamboo shoots have certain risks in terms of high lead level.
基金Supported by Natural Science Foundation of Guangdong(S2013010013693)Outstanding Young Teacher Training Program of Colleges and Universities in Guangdong Province(Yq2013152)
文摘Concentrations of lead( Pb),cadmium( Cd),chromium( Cr),copper( Cu),zinc( Zn) and manganese( Mn) were measured in various organs( such as in liver and muscle) from 9 species of freshwater economic fishes which were collected from northeast area of Guangdong Province. The concentration of metals was measured by inductively coupled plasma atomic emission spectrometry( ICP- AES). Results showed that the levels of metals in hepatopancreas of the fishes were found in order of Zn > Pb > Cu > Hg > Cd,while in muscles were Zn > Cr> Pb > Mn > Cu > Cd. In general,the metals concentrations were significantly higher in liver samples than that in muscle samples. Based on the " pollution index of single factor",the fishes,to one degree or another,were polluted by Pb,Cd,Cr,Cu and Zn,and pollution levels were mostly followed by Pb > Cd > Cr > Cu > Zn. The indexes of Pb and Cd tested in hepatopancreas of the fishes were in a majority exceeded the national safety criteria for food in China. What's more,it was found that the contents of the heavy metals in fishes did not vary with the trophic level which they belong to. In summary,the fishes were polluted by Pb,Cd,Cr,Cu and Zn to some extent,which indicated that hidden danger of heavy metals pollution was present in ecological environment or safety in fishery production in the area.
基金Key Research and Development Project of Guangxi(Gui Ke AB18221056)Guangxi Innovative Team Building Project in Earmarked Fund for China Agriculture Research System(nycytxgxcxtd-04-02)Special Fund for Innovation-driven Development in Guangxi(Gui Ke AA17204064)。
文摘[Objectives]This study aimed to explore the effect of different concentrations of selenium fertilizer on the yield,selenium content and heavy metal contents of waxy maize,thereby providing reference for the scientific application of selenium fertilizer on waxy maize.[Methods]Different varieties of waxy maize(Guitiannuo 611,Guinuo 615 and Guiheinuo 609)were used as test materials.They were sprayed with different concentrations(0,0.5,1.0,1.5 and 2.0 g/L)of water-soluble selenium fertilizer(Xinxibao)at the big flare stage,and the effect on the yield,selenium content and heavy metal contents of the waxy maize was analyzed.[Results]Foliar application of different concentrations of selenium fertilizer showed no significant effect on the yield and yield components of waxy maize.As the concentration of selenium fertilizer increased,the grain selenium content of different varieties of waxy maize increased.Among them,the increase of Guinuo 615 was the largest,of which the selenium content reached 0.265 mg/kg,2.82 times that of the control(water).The cadmium and arsenic contents of different varieties of waxy maize decreased with the increase of the concentration of selenium fertilizer sprayed.Among the waxy maize varieties,the cadmium and arsenic contents of Guitiannuo 611 dropped the most significantly,up to 52.94%and 77.78%.In waxy maize,the correlation coefficients between selenium content and cadmium,arsenic contents were-0.5509(P<0.05)and-0.8530(P<0.01),respectively.[Conclusions]Spraying exogenous selenium fertilizer had no obvious effect on the yield of waxy maize.However,the increase of the concentration of exogenous selenium fertilizer could significantly increase the selenium content and reduce the cadmium and arsenic contents in grains of different varieties of waxy maize.
文摘In order to determine and assess the concentrations of trace elements in coral reefs sediments from Red Sea of Yemen,sediment samples were collected,treated and analyzed for cadmium,chromium,cobalt,copper,manganese,nickel,iead,iron,zinc and vanadium by the atomic absorption spectrometric analysis.The result is that cadmium,cobalt and lead concentrations were high and other elements are low or the same as natural background.It is concluded that the high cadmium,cobalt and lead levels in coral reefs sediments will have negative effects on marine life of the sites,so further researches are needed to characterize the sources fate,biogeochemical processes and impacts of these trace elements on coral reefs and marine of the region.
文摘Spices are generally consumed because of their medicinal properties, taste, and add flavor to food. Objectives: To determine the nutrient contents and heavy metals of five commonly consumed spices, namely turmeric (Curcuma longa), bay leaf (Laurus nobilis), red chili (Capsicum annuum), coriander (Coriander sativum), and black cumin (Nigella sativa) were collected from the local market of Northern zone, Bangladesh and were analyzed. Methods: Nutrient composition was assessed by proximate analysis, trace and heavy metals by atomic absorption spectrophotometry while the indophenol method was used to determine vitamin C. Result: The results revealed that spices are good sources of carbohydrate, fiber, and fat. The highest levels of carbohydrates, dietary fiber, protein, and fat were observed in turmeric (71.1%), black cumin (40.0%), red chili (16.77%), and coriander (17.8%) respectively. Vitamin C was present in trace amounts ranging from 0.04 to 0.1 mg/100g, except black cumin (35.0 mg/100g). Essential trace minerals like sodium, potassium, calcium, magnesium, and iron were significantly present in black cumin and bay leaf. Most of the heavy metal levels in the spices were appreciable amounts i.e. much lesser than the statutory safe limit approved by WHO and FAO for some of the samples. Conclusion: The current study concluded that the investigated spices are nutritionally rich, and heavy metal levels in the examined samples are safe for human consumption.
基金Supported by Enterprise Science and Technology Commissioner Project of Guangdong Province(GDKTP2020020800)Natural Science Foundation of Guangdong Province(2021A1515010851)+1 种基金Undergraduate Innovation and Entrepreneurship Project(S202110576028X,202010576002X)Science and Technology Innovation Strategy Special Fund Project of Guangdong Province(pdjh2021b0455)。
文摘In order to explore the application effect of the comprehensive control technology of"soil conditioning-organic planting-foliar control"in the rice area of northern Guangdong,the effects of combined application of different dosages of soil conditioner,bio-organic fertilizer and foliar control agent on heavy metal contents and yields of early and late rice were investigated based on field experiments.The results showed that different treatments of early rice and late rice all increased the yield.The yield increase rates of treatments 2,3 and 4 reached 4.9%,7.2%and 8.7%in early rice,respectively,and those in late rice reached 7.7%,7.8%and 9.7%,respectively.And the cadmium contents of early rice and late rice in treatments 2,3 and 4 were significantly reduced below the safe value.Taking into account factors such as cost,yield increase rate,and heavy metal compliance rate,the recommended application rate for early and late rice is conventional fertilization+soil conditioner 6000 kg/hm^(2)+bio-organic fertilizer 1800 kg/hm^(2)+foliar control agent 6000 ml/hm^(2).
文摘A study was conducted to assess the heavy metal (As, Pb, Cd, Cr, Cu, Zn and Hg) contents of different sources of wastes generated in Dhaka city which was further used for a compost plant. The study consisted of both field survey and laboratory analyses. Relevant primary and secondary sources of data were collected to identify the source and nature of wastes generated near the compost plant. A total of eight households, ten officers and ten waste collectors were surveyed for data collection. For laboratory analyses, wastes from various socio-economic niches (lower, lower middle, middle and high) were collected. The result showed that wastes generated in the lower income niche contained the minimum contents of heavy metals compared to middle and high niches. The increasing trend of heavy metal contents of the wastes from lower to high income groups has been found to be linked to the life style, attitude, profession, culture and food habit. Most of the heavy metals did not meet the standard level for almost all the niches. Most of the correlations were found to be insignificant between the contents of nutrient element (C, N and P) and heavy metals (As, Pb, Cd, Cr, Cu, Zn and Hg).
