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1.
In order to control heavy metal pollution effectively, this paper reviews heavy metal source and transport characteristics in heavy metal circulation in bio- sphere, including geochemical cycle and biological cycle of heavy metals. The inter- body of geochemical cycle of heavy metals includes soil, gas as well as water body, and the interbody of biological cycle of heavy metals includes environment, plant, microorganisms and animals. As to macro-cycle, transportation character in each interbody is different. Heavy metal circulation in different interbody interacts with each other and is in dynamic balance. Heavy metals in soil include two parts, i.e. active and inert forms, which are in dynamic equilibrium. This equilibrium may be affected by different physicochemical factors. Heavy metal content at different soil depth reflects historical accumulation level of heavy metal. In contrast to agri- cultural eco-system itself, industrial and urban activities are of great menace. Fluvial transport and atmospheric input are significant pathways of heavy metal circulation. Sludge plays an accumulative role of heavy metals, and can release its heavy met- als to water body causing secondary pollution. Balance of heavy metal immobiliza- tion and release is interrupted by physicochemical characters and microbial activity. Temperature can influence atmospheric heavy metal content, and volatile heavy meal precipitation is an indLspensable source in soil and water body. In regard to micro-cycle, plants is the main part in heavy metal cycle, microorganisms play roles in accelerator and animals in recipient. Specific transportation and assigned location of heavy metal in plants are adopted to keep internal heavy metal equilibrium.  相似文献   

2.
This paper, probing into heavy metal control in domestic rubbish by source screening and nutrient element analysis, revealed the feasibility of source control of heavy metals and the suitability of rubbish as turfgrass medium. Heavy metals in domestic rubbish were controlled by source screening before composting. The study consisted of a control with garden soil. The contents of main mineral elements and heavy metals in rubbish compost and control were determined by the method of ICP-AES. The results showed that heavy metal concentrations in rubbish were lower than those in garden soil, and little difference occurred between rubbish and garden soil in main mineral element concentrations. Based on this, it was concluded that rubbish compost was favorable for using as turfgrass medium and heavy metal control in rubbish by source screening was effective.  相似文献   

3.
Northeast of China and Jiangsu Province are major production areas of japonica rice in China.Rice from northeast of China is well-known for its good-eating and appearance quality,and that from Jiangsu Province is viewed as inferior.However,little is known concerning the difference in physicochemical and sensory properties of rice between the major two production areas.Analysis of 16 commercial rice samples showed marked differences in physicochemical properties,including chalky grain rate,contents of amylose and protein and pasting properties between the two main areas.Northeastern rice contained more shortchain amylopectin as compared with Jiangsu rice.However,Jiangsu rice is comparable to northeastern rice in terms of sensory quality including overall acceptability and textural properties of springiness,stickiness and hardness as evaluated by trained panel.Our results indicated the limitation of conventional index of physicochemical properties,and suggested the necessity of identification of new factors controlling rice sensory property.In addition,the taste analyzer from Japan demonstrates limitation in distinguishing the differences between northeastern and Jiangsu rice,and therefore needs localization to fit China.  相似文献   

4.
Heavy metal accumulation and its influential factors were studied in the different land use soils, which would provide a theoretical basis for controlling the content of heavy metals in soils. To identify the effects of land use on the accumulation of heavy metals in soils, 148 soil samples were collected from four land use patterns including greenhouse field, uncovered vegetable field, maize field, and forest field in Siping area of Jilin Province, China, and Cr, Ni, Cu, As, Cd, Pb, and Zn contents of those samples were determined with ICP and ICP-Mass. The result showed that there was a rather large difference in effects of the accumulation of Cr, Ni, Cu, As, Cd, and Zn in soils under different land use patterns, except Pb. Based on the assessment which compared with background concentrations in soil, the higher accumulation of heavy metals was found in greenhouse and uncovered vegetable field, much less in maize field and forest field. The mean contents of heavy metals in soils from high to low were arranged in order of greenhouse field, uncovered vegetable field, maize field, and forest field. Cd and Cu had relatively serious accumulation in soils compared to Cr, Ni, As, and Zn. The mean content of Cd in greenhouse field was 0.467 mg kg-x,which exceeded the grade II of the Chinese Soil Quality Criterion GB15618-1995 (6.5 〈pH〈7.5) for Cd standard of 0.3 mg kg^-1, while it was 5.2 times of Cd standard in the forest fields. The mean contents ofCr, Ni, Cu, As, Pb, and Zn in soils under four land use patterns were lower than the grade II of the Chinese Soil Quality Criterion. Compared with the soil cultivated years, the agricultural chemical compounds and manures application, especially the quality and quantity of applied fertilizer was one of the main reasons for leading to different accumulation of heavy metals in soils under the studied land use patterns. The accumulation of heavy metals, such as Cr, Ni, Cu, As, Cd, and Zn in soils was significantly affected by land use patterns, among them the accumulation of heavy metals in greenhouse soils was higher than others. It is suggested that the application of chemical fertilizer, organic fertilizer, and pesticides with high contents of heavy metals should be avoided to prevent the accumulation of heavy metal and keep high quality soils for sustainable use.  相似文献   

5.
[Objective] The inductively coupled plasma mass spectrometry(ICP-MS)was constructed to determine the contents of lead,cadmium,mercury and arsenic in Archyranthes bidentata Blume.[Method]Under the optimum operation condition of ICP-MS,the samples were digested by microwave.The element 114In was taken as an internal standard element to compensate body effect and ICP-MS method was used to determine the contents of lead,cadmium,mercury and arsenic.[Result]For the determined elements,the correlation coefficient(r)of standard curve was over 0.9995 and recovery rate was from 96.7% to 106.4% while RSD was less than 11.2%.The result of determination showed that the heavy metal content in Archyranthes bidentata Blume.beyond standard was serious.[Conclusion]The constructed ICP-MS method with simple operation,rapid response,accuracy and high sensitivity in this experiment could be used for quality control of Chinese medicinal materials by detecting heavy metal contents in different Chinese medicinal materials from original places.  相似文献   

6.
This study aimed to analyze the relationship between nutrient elements K, Ca, Mg, Cu, Mn, Zn and Fe in tobacco-planting soils and tobacco leaves from six main tobacco-producing areas, and to investigate the influences of these elements on chemical composition and aroma components in tobacco leaves. Results showed that there were certain relationship between contents of nutrient elements in tobac- co-planting soils and contents of corresponding elements in tobacco leaves; various elements exhibited different influences on the aroma quality of flue-cured tobacco. Based on the actual situation of nutrient contents in soils from different tobacco- producing areas, contents of various elements in tobacco leaves should be regulat- ed by soil fertilization and foliar spraying, thereby improving the aroma quality of flue-cured tobacco.  相似文献   

7.
Development of new technologies for evaluating genetically modified(GM) crops has revealed that there are unintended insertions and expression changes in GM crops.Profiling techniques are non-targeted approaches and are capable of detecting more unintended changes in GM crops.Here,we report the application of a comparative proteomic approach to investigate the protein profile differences between a GM rice line,which has a lysine-rich protein gene,and its non-transgenic parental line.Proteome analysis by two-dimensional gel electrophoresis(2-DE)and mass spectrum analysis of the seeds identified 22differentially expressed protein spots.Apart from a number of glutelins that were detected as targeted proteins in the GM line,the majority of the other changed proteins were involved in carbohydrate metabolism,protein synthesis and stress responses.These results indicated that the altered proteins were not associated with plant allergens or toxicity.  相似文献   

8.
The effect of brown rice and corn-based diets on fatty liver weight, carcass traits, lipids accumulation and liver composition of Landes geese (Anser anser) after feeding the same amount of each diet was investigated. After 2 weeks overfeeding,besides body weight and body weight gain increased significantly, the fatty liver weights were increased dramatically from 94.67 to 554.67 and 754.00 g in corn treatment and rice treatment, respectively, and the accumulation lipids in adipose tissues reached up to or close to 2 folds of initial weight in both treatments. Liver weight was greater in brown rice group than in corn group (P<0.05). Compared to before overfeeding, triacylglycerols (TG) in geese fatty liver increased dramatically and predominated (from 9.08% to close to or more than 90% of hepatic lipids), whereas phospholipids (PL) and cholesteryl esters (CE) decreased sharply in both treatments (P<O.05). However, the percentages of lipids, TG and PL in fatty liver were higher in brown rice treatment than in corn treatment, and that of CE was lower (P<O.05). It indicates that overfeeding chiefly results in lipids accumulation in goose fatty liver and adipose tissues. Brown rice-based diet induces greater fatty liver, and brown rice is one of high quality overfeeding ingredients instead of corn.  相似文献   

9.
Maize-rice cropping systems are expanding in Bangladesh. Hybrid maize has increasing demand and value, particularly for poultry feed, while rice remains the traditional dominant starch staple food. Bangladesh maize yields (with average farm yields around 5.7 t·ha^-1) are among the highest found in Asia. Cool winter (Rabi) season maize followed by T. Aman (monsoon) rice is the major cropping system; however it is now becoming diversified with many other crops including potato. Financially, hybrid maize is far more profitable than boro (irrigated) rice, wheat, or most other competing winter season Rabi crops. Although maize is relatively problem-free in Bangladesh, some constraints are intensifying with increased concern over input supply and soil-related environmental sustainability. An array of new technologies for sustainable intensive maize production systems is emerging in Bangladesh and some are being promoted and adopted. Continued sustainability of hybrid maize production in Bangladesh depends on optimization of planting time, quality seed of appropriate hybrids, balanced use of nutrient inputs along with soil fertility conservation and other management, for which further research would be high priority.  相似文献   

10.
The resultant climate change on sustainable food supply has greatly affected agricultural production by the level of great volumes of gasses emitted into the atmosphere by human activities. The human factors that emit large amount of green house gases include industrialization, burning of fossil fuel and gas flaring. Increase in air temperature and consequent increase in the rates of evaporation also affect the level of food supply. Data for this study were collected from primary and secondary sources. Primary source were collected through field investigation and structured questionnaire. A total of 450 questionnaires were administered. Results revealed that varieties of crops ranging from tree crops to cereals were cultivated within the study area. The effect of climate change on food supply has resulted into change in crop yields, change in rainfall pattern, soil loss and has greatly affected planting period and harvesting. The study therefore recommended awareness campaigns on the causes and consequences of global climate change on food production, environmental education and afforestation campaign programmes on sustainable food supply and environmental safety must be intensified.  相似文献   

11.
陕蒙高速两旁粮食作物中重金属含量分析   总被引:1,自引:0,他引:1  
为了研究陕蒙高速公路的开通对公路旁粮食作物生产带来的影响,笔者以陕蒙高速南段的王则湾为样区,采用原子吸收法对公路边水稻和玉米根、茎、叶的消解液中重金属(Zn、Pb、Cu、Cb)含量进行测定。结果表明公路对玉米和水稻中重金属元素积累有显著作用,与无公路影响的对照样进行比较,2个样区中2种粮食作物的重金属含量均超标,表明高速路旁100m范围内种植的粮食作物(特别是距路基40m范围)正受到重金属的污染,污染原因主要与高速公路的开通直接相关。据此,笔者认为,公路主干道100m范围内不适宜种植粮食作物。  相似文献   

12.
陕蒙高速公路两旁粮食作物中重金属含量分析   总被引:14,自引:1,他引:13  
1试验方法1.1研究地点概况1.1.1地理特点。位于陕西境内的陕蒙高速公路沿线为案例研究区,路线所经地段均在毛乌素沙漠区,全长88.1km,起于榆林市榆阳区孙家湾村,与榆靖高速公路相连。样品采集地点为王则湾,位于陕蒙高速公路的榆林以北10km处。该农田样区四周开阔,与公路间无遮挡,无明显的工业污染源,土壤质地均为沙壤土。公路为南北走向的柏油马路。  相似文献   

13.
焦作煤矿区成熟作物中重金属Pb·Cr·Zn·Cu富集特征研究   总被引:2,自引:0,他引:2  
[目的]探明焦作煤矿区成熟作物的重金属的富集特征。[方法]采用扇形布点法在焦作煤矿周边农田区采集土壤和小麦、玉米等样品,测定土壤和作物中的Cu、Zn、Pb和Cr4种重金属元素含量。[结果]土壤中Zn、Pb和Cu已开始富集,但Cr无富集,甚至亏损。成熟玉米籽粒和茎叶的重金属元素富集顺序分别为:Zn>Cu>Cr>Pb和Cu>Pb>Zn>Cr;成熟小麦籽粒、茎叶和根部的富集顺序分别为:Zn>Cu>Cr≈Pb,Cu>Pb>Zn>Cr和Zn>Pb>Cu>Cr。Pb和Cu在玉米不同部位分布顺序为:茎叶>籽粒;Cr和Zn在玉米中分布为:籽粒>茎叶。Pb在小麦不同部位含量分布为:根部>茎叶>籽粒;Cr和Cu在小麦中分布为:根部>籽粒≈茎叶;Zn在小麦中分布为:根部>籽粒>茎叶。[结论]作物对于重金属的累积因作物和重金属类型的不同而异。  相似文献   

14.
[目的]研究贵州SQ、DX典型铅锌矿区种植的水稻、玉米与其土壤中重金属的污染状况,为矿区环境保护、农业生产提供参考。[方法]以该矿区18个水稻籽、15个玉米样品与其土壤中重金属含量为对照,采用单项污染指数法和综合污染指数(内梅罗指数)法研究铅锌矿区土壤-农作物体系重金属含量间的相关性。[结果]研究结果表明,水稻籽、玉米中Cu、As的单因子污染指数小于1,Pb、Cr、Hg、Cd的单因子污染指数大于2,已造成农作物污染。采用综合污染指数评价,该矿区种植的水稻籽、玉米已受重金属污染。[结论]除Cu、As、Zn外,水稻籽、玉米中的其他重金属含量与土壤中的相应重金属含量显著相关,说明这些元素较易从土壤向水稻、玉米植物体内迁移积累。  相似文献   

15.
为揭示大气降尘对作物生长和农产品品质的影响,采用不同来源和不同程度的降尘,模拟开展降尘-农作物盆栽试验,分析青菜和水稻幼苗光合及呼吸速率、叶绿素含量、地上部干物质质量以及重金属含量的变化。结果表明,大气降尘显著抑制了2种农作物的光合速率,降低了叶片中叶绿素含量,同时提高了呼吸速率,导致青菜和水稻幼苗地上部干物质质量分别下降了11.8%~51.3%和12.7%~35.5%。大气降尘使青菜和水稻幼苗植株中部分重金属元素含量显著增加,农作物安全品质降低。  相似文献   

16.
为了给菌糠改善土壤重金属污染提供理论参考,探究菌糠对污灌区种植不同作物的土壤中重金属铜和铬形态的影响,针对污灌区土壤,采用田间试验,对玉米、高粱、糯玉米3种作物基施菌糠后,在作物成熟期采集土壤样品,研究了重金属铜、铬总量及不同形态的分布变化。结果表明:菌糠的施用增加了污灌区土壤中铜、铬总量的降低幅度,与不施菌糠相比,3种作物种植后土壤中的铜、铬总量都呈现减少趋势。在不施用菌糠土壤中,Cu含量减少率在3.17%~16.20%,Cr含量减少率在5.00%~15.40%;在施用菌糠的土壤中,Cu含量减少率在6.17%~18.60%,Cr含量减少率在8.94%~20.60%;菌糠的施用提升了碳酸盐结合态、有机结合态、残渣态铜和铬的减少率,除可交换态铜含量呈增加趋势外,其余各形态铜和铬均呈减少趋势。3种土壤中,种植玉米的土壤中铜、铬各个形态的含量减少率显著高于种植其他两种作物的土壤,这与土壤中铜、铬全量的减少率规律一致。除种植玉米的土壤中铁锰氧化物结合态铜的含量外,种植其他两种作物的土壤施加菌糠后,铜、铬各个形态含量的减少率均高于不施用菌糠土壤,说明施用菌糠可以促进重金属铜和铬碳酸盐结合态、有机结合态、残渣态的减少,降低土壤中的重金属含量。  相似文献   

17.
中国土壤模式-作物系统重金属生物富集模型建立   总被引:9,自引:5,他引:4  
针对土壤模式建立土壤和作物重金属含量关系模型,旨在消除土壤属性对作物重金属吸收量的影响。当作物类型或品种确定后,作物重金属吸收量只与土壤重金属含量有关。提出了农田作物重金属生物富集的"土壤重金属含量-作物特性-土壤属性"关系理论,定义了土壤模式、土壤模式-作物系统重金属生物富集模型、土壤模式-作物系统重金属生物富集模型图谱等概念,确定了土壤模式的划分方法和使用方法,在此基础上以最近30年来中文期刊发表的土壤镉含量与水稻和小麦镉含量关系作为案例验证了以上方法。结果表明:水稻和小麦同一部位镉吸收量随土壤镉含量增加而增加,水稻和小麦吸收镉能力顺序为根>茎>叶>籽粒,水稻和小麦籽粒镉吸收量在同一范围内。  相似文献   

18.
以油菜、小麦、玉米和水稻秸秆为调理剂,与城市污泥混合进行好氧堆肥,研究了不同作物秸秆作调理剂对城市污泥好氧堆肥产品重金属质量分数及形态的影响.结果表明:好氧堆肥使堆体中Cd,Pb和Cr 3种重金属质量分数升高,使Pb,Cr可交换态质量分数及生物有效性降低,但不能降低Cd的生物有效性.其中,添加玉米秸秆有利于Cd的碳酸盐结合态向残渣态转化;添加油菜和水稻秸秆促进Cr分别向有机结合态和残渣态转化;添加玉米秸秆能有效降低Pb碳酸盐结合态质量分数,而水稻秸秆更有利于Pb向残渣态转化.表明4种秸秆作为调理剂对重金属形态的影响有一定的差异,对不同的重金属钝化效果不同,应根据污泥中的重金属选择合适的调理剂.  相似文献   

19.
铜陵市凤凰山尾矿区重金属污染研究   总被引:1,自引:0,他引:1  
惠勇  张凤美  王友保  郭凯  张洁  谈成林 《安徽农业科学》2011,39(23):14268-14269
[目的]铜尾矿库的修复及以后的相关研究提供科学依据。[方法]采用火焰-原子吸收分光光度计和石墨炉原子吸收分光光度法测定土壤中重金属含量。[结果]尾矿土壤中的Cu、Zn、Cd含量均较高,其中Cu、Cd的含量分别是国家土壤环境质量二级标准的1.04~1.30倍和6.58~9.34倍。[结论]重金属污染会降低土壤质量,进而影响该地区作物的质量。凤凰山尾矿区近年来种植的作物,对重金属元素的吸收效果不明显。这为后期的土壤改良和种植作物的选择提供了一定的依据。  相似文献   

20.
北京市主要路旁绿化灌木中重金属元素分布特征   总被引:1,自引:0,他引:1  
分析了北京市7种主要路旁绿化灌木的重金属元素质量分数。结果表明:7种优势植物对重金属元素有不同程度的积累,但积累量均未达到超积累植物所规定的临界含量。小叶女贞和紫叶小檗对重金属的转运能力(向地上部分)较强,对重金属污染土壤有一定的修复潜力。植物各器官对重金属元素的吸收受土壤中重金属元素质量分数的影响。从对重金属的富集吸收能力来看,根最强,茎次之,叶最弱,趋势明显。小叶女贞、紫叶小檗、小叶黄杨对重金属的富集能力都较强,是对抗重金属污染的最佳选择。  相似文献   

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