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1.
有机氯农药(Organochlorine Pesticides,OCPs)是一类由人工合成的杀虫广谱、毒性较低、残效期长的化学杀虫剂。本文以汕头市为研究区域,探讨了土壤OCPs的残留现状和特征,并对该区的土壤进行了环境质量评价和初步的生态风险评价。结果表明:(1)汕头地区土壤中OCPs的检出率高达99.13%,OCPs残留量的平均值是113.37 ng·g^-1,主要的OCPs污染物为DDTs和硫丹类;南澳县OCPs残留量平均值最高(174.68 ng·g^-1),其次为龙湖区,濠江区含量平均值最低(69.24 ng·g^-1);(2)与国内外一些地区土壤中OCPs的残留量对比,本研究区域土壤中的OCPs处于中等污染残留水平;与美国马里兰州标准、纽约州可容许的土壤浓度标准和我国的土壤环境质量标准相比较,OCPs基本没有超标;(3)本研究地区土壤存在较高的生态风险,OCPs可能对环境造成一定的危害,其中生态风险最高的是DDTs,BHCs的生态风险较低。  相似文献   

2.
对常规种植的长兴、昆山和有机种植的溧阳、溧水农田灌溉水进行了采样监测,并参照农田灌溉水质标准(GB 5084—2005)和地表水环境质量标准(GB 3838—2002),分别采用单项指数法(Pi)和综合指数法(P综)对常规种植和有机种植的7个农田灌溉区24个水质样品进行灌溉水质量的分析与评价。结果表明:灌溉区的水质总体良好,其中常规种植的长兴样点Pi中Zn元素严重超标,P综为9.529,属重度污染,昆山样点Pi为0.277,尚清洁;有机种植的溧阳、溧水(L1、L2、L3、L4)样点Pi处于安全等级,综合评价为清洁。相关分析显示,水质pH、EC25℃、化学物质和重金属元素之间呈正相关,且锌与铬、镉与砷有其同源性。  相似文献   

3.
南充农村土壤中有机氯农药残留现状分析   总被引:1,自引:0,他引:1  
本研究以四川省南充市某农村土壤为研究对象,于2010年和2011年连续两年对土壤中有机氯农药(HCH,DDT)残留情况进行了定点监测。研究结果表明,试区土壤HCHs在2011年基本未检出。两年的DDTs的检出率均为100%。OCPs主要残留物为p,p’-DDE,占残留总量75%以上。不同利用类型土壤中有机氯残留总量排序为:菜地>重点污染场地>基本农田>居民聚集区。所有土壤样品中的HCHs含量均达到国家《土壤环境质量标准》(GB15618-1995)一级标准(<0.05mg/kg),DDTs含量均达到二级标准(<0.50mg/kg)。残留污染较轻。  相似文献   

4.
为了调查淄博市POPs的污染水平,在全市不同功能区设置了5个采样点,采集了采暖期和非采暖期大气颗粒物样品。在对颗粒物样品进行前处理后,通过GC/MS和GC-ECD,分析测定了颗粒物上PAHs、PAEs、PCBs和OCPs四类典型POPs的浓度。结果表明,淄博市市区混合区和县城混合区污染较为严重,采暖季污染较非采暖季严重,这归因于采暖季燃煤量的增加。PAHs成分以4~6环为主,PAEs以DBP和DEHP为主,PCBs污染主要以四氯联苯、五氯联苯和六氯联苯为主,OCPs中含量最高的是艾氏剂和狄氏剂。  相似文献   

5.
为发展无公害农产品基地提供科学依据,2005年对浙江省宁波市鄞州区100个农业土壤样品中重金属含量进行了测定和评价。结果表明:耕层全砷、镉、铬、汞和铅的平均含量分别为8.1mg·kg^-1,0.163mg·kg^-1、100.1mg·kg^-1、0.257mg·kg^-1和3.6mg·kg^-1,与1983年宁波市的耕层土壤背景值相比,分别增加了12.5%、32.5%、61.2%、0.8%和55.2%,土壤已受到镉、铅和汞的轻微污染,而汞的污染已得到遏制。从总体上来说,鄞州区农业土壤环境质量良好,区内有98个点(占总样点数的98%)符合无公害农产品产地土壤环境质量要求,但有2个点(占总样点数的2%)分别受到镉和汞的污染。  相似文献   

6.
铜陵铜官山矿区土壤重金属污染状况研究   总被引:2,自引:0,他引:2  
通过野外调查和室内分析,研究了铜陵铜官山铜矿区土壤重金属含量,并采用单因子指数法和内梅罗指数法对铜官山土壤污染程度进行评价.研究结果表明,研究区土壤Cu、Zn、As、Hg平均含量高于当地的土壤背景值,土壤已受Cu、Zn、As重污染,受Hg轻污染.不同样点土壤重金属含量存在较大差异,其中处于选矿厂附近的9到16号样点土壤重金属污染情况较其它样点相对较重,15和16号样点的重金属单项污染指数和综合污染指数都很高,污染状况在所有样点中最为严重.  相似文献   

7.
抽取浙西南地区28个茶叶样品及相应茶园土壤样品,检测分析了茶园土壤Pb、Cd、Cu及春茶、秋茶Pb、cd、cu、稀土含量,并结合茶园土壤和茶叶的卫生标准,采用单因子污染指数、单因子综合污染指数和Nemerow污染指数法进行污染评价。结果表明:该地区茶园土壤和茶叶总体未受到Pb、cd、cu污染,个别茶叶样品受到Pb和稀土的轻度污染;土壤单因子综合污染指数P均小于0.6,综合污染指数P镕小于0.7,基本符合土壤一级标准。  相似文献   

8.
采用加速溶剂萃取,气相色谱-质谱法测定了杭州市城区蔬菜地中农药残留量,并进行了评价。结果表明:杭州市城区蔬菜地中有机氯类、有机磷类、拟除虫菊酯类农药残留量为ND~0.19mg·kg^-1、ND~0.238mg·kg^-1、ND~0.013mg·kg^-1,检出率为52.4%、33.3%和28.6%。其中有机氯类农药达到国家土壤环境质量标准(GB15618—1995)二级以上,符合无公害蔬菜产地环境要求;根据加拿大残留限量标准评价有机磷类农药,超标率为14.3%;拟除虫菊酯类农药对土壤造成的污染不论是残留量还是检出率都小于前2类农药。  相似文献   

9.
矿山开采和冶炼可对矿区土壤造成不同程度的重金属污染。为了明确吉林省镍矿区耕地土壤/植物体系中重金属的迁移累积规律,在吉林省镍矿区采集了27个区域的土壤和玉米植株样品。结果表明,吉林省镍矿区土壤p H为5.00~6.82,有机质的含量为2.79%~7.93%,部分采样点的Cd和Pb超出吉林省土壤背景值,大部分采样点的Cu和Ni超出吉林省土壤背景值,所有采样点的Zn超出吉林省土壤背景值。玉米籽粒中Cd和Pb未检出,玉米茎中Cd未检出,27个采样点中有23个采样点的玉米籽粒Ni含量超过我国粮食及制品中重金属限量标准(NY 861-2004),而仅有4个采样点的籽粒Zn含量超过我国限量标准,所有采样点的籽粒Cu含量明显低于我国限量标准。随土壤重金属全量增加,玉米根Cd,Cu,Ni,Pb和Zn含量均呈增加趋势,其中根Cd,Cu,Ni含量与土壤重金属Cd,Cu,Ni全量呈显著正相关,而根Pb和Zn含量与土壤重金属Pb和Zn全量相关性不显著。  相似文献   

10.
为了评价70%甲基硫菌灵可湿性粉剂在番茄中的使用安全性,开展甲基硫菌灵在番茄中的残留量研究。本文建立了分散固相萃取前处理,高效液相色谱/质谱联用法测定甲基硫菌灵在番茄中残留量的方法。样品经乙腈提取,乙二胺-N-丙基甲硅烷(PSA)和无水硫酸镁混合振荡离心除去杂质和水分,上清液用配有电喷雾(ESI)源的高效液相色谱/质谱联用仪测定。田间试验结果建议在番茄上喷施70%甲基硫菌灵可湿性粉剂562.5 g ai·hm^-2,3次施药,推荐安全间隔期为3 d;市场抽检样品检测表明番茄中甲基硫菌灵的残留量均小于0.05 mg·kg^-1,低于最大残留限量3 mg·kg^-1。  相似文献   

11.
基于各3种采集环境样本、国家标准物质的土壤和沉积物,以当前环境监测行业常用的3种消解方法,探讨20种混合酸系统条件在消解条件变化中对复杂样本硒元素测定的影响。确定了最佳土壤和沉积物消解的组合为王水系统(盐酸∶硝酸∶氢氟酸∶过氧化氢∶高氯酸=3∶1∶1∶1∶1),各消解法的处理结果部分(n=5)∶水浴法消解时间仅需0.5h,总处理时间2h,准确度回收率达101%~104%,精密度RSD为1.95%~2.20%;电热板法总处理时间较长(7.5h),回收率106%,RSD偏高为8.46%,不推荐使用;微波法处理的总时间亦长达7.0h,回收率93.8%,但精密度亦偏高为8.24%,因此采用水浴法应用于环境样本的测定。该优化消解方法已直接应用于环境中农业、建筑用土和管道淤泥沉积物的3种样品类型前处理,利用同一优化条件即可快速对应土壤和沉积物性质样品,单次可批量处理72~84个样本,解决高通量样品痕量硒测定需求,提供环境污染监测和检测行业一参考依据。  相似文献   

12.
针对石油污染土壤中VOCs含量的应急监测,便携式气相色谱-质谱联用仪适用于土壤中甲苯、乙苯、二甲苯、三氯苯等13种苯系物的快速定量检测,通过对某废弃炼油厂土壤样品测定,该方法在快速定性的同时,定量测定5~20411μg/kg土壤样品具有很高的可靠性。  相似文献   

13.
A selective separation and quantitative determination procedure for 210Pb and 210Po in various environmental matrices from different sources such as IAEA-326 soil, phosphate rocks (PR), and phosphogypsum (PG) was developed. The tested samples were digested sequentially using concentrated mineral acids (HF, HNO3) by a programmable high-pressure microwave digestion system. The sample solution was loaded onto a preconditioned ion exchange column (Sr-resin) for chromatographic separation. Polonium-210 was eluted by 6 M HNO3 then spontaneously deposited onto polished silver discs to be measured using low-background alpha spectrometry. Lead-210 was sequentially eluted using 6 M HCl solution, precipitated as lead oxalate, dissolved in HNO3 solution, and mixed with scintillation cocktail to be measured by liquid scintillation counting (LSC). Performance of the developed procedure was tested using a reference soil (IAEA-326), with recommended isotope values, that was used as a quality control to assess separation and quantification efficiency (recovery %). The minimum detectable activities of 210Pb and 210Po were found to be 24 and 0.28 Bq kg(-1) for the measurements using LSC and alpha spectrometry, respectively. The recoveries (%) of 210Pb and 210Po were found to be 80 and 60%, respectively. To test the validity of the proposed LSC method, a comparative study was performed by measuring 210Pb activity concentration in test samples by nondestructive gamma-ray spectrometry.  相似文献   

14.
应用硝酸微波消解土壤样品-冷原子吸收法测定土壤中的汞。通过正交试验,优化了土壤中汞的微波消解条件。并对干扰消除、方法精密度、加标回收、检出限进行了试验研究。在0~10μg/L范围内线性关系良好,方法测定下限为0.20μg/L,土壤中汞的检出限为0.005μg/g。该优化条件对汞含量为0.02—0.46μg/g的土壤样品,汞提取完全。建立了一种简便、成本低、干扰少、灵敏度高的方法。  相似文献   

15.
为了客观分析土壤中硒形态分布特征及硒有效性影响因素,依据硒不同形态下的溶解度不同,采用四步五态连续浸提取技术,由弱到强的选择顺序提取僰王山镇水田土壤中硒的水溶态、可交换态、有机质结合态、硫化物/硒化物态、残渣态这5种形态,并用原子荧光光谱法分析和氢化物发生-原子荧光光谱法测定了土壤样品中5种形态硒和总硒的含量。初步总结了研究区水田土壤硒含量特征和硒形态分布特征。研究结果发现,僰王山镇水田土壤总硒含量变化范围为0.51~0.93 mg/kg,平均值0.714 mg/kg,远远超过全国土壤总硒平均值0.290 mg/kg,且超过了目前认为的富硒土壤的标准值0.4 mg/kg。从土壤中5种形态分析结果所占比例来看,有机质结合态和硫化物/硒化物态硒是硒元素的主要赋存形态,两者占土壤总硒含量的54.63%,反应了研究区土壤中硒富集与有机质结合态存在密切关系。  相似文献   

16.
Increasing antibiotic resistance genes in the environment may pose a threat to public health. In this study, tetracycline and sulfonamide resistance genes (Tet-W, Tet-O, and Sul-I) were quantified in 24 manure samples from three farms and 18 biosolids samples from seven different wastewater treatment plants using quantitative polymerase chain reaction methods. Concentrations of Tet-W and Tet-O genes were observed to be significantly higher (p < 0.05) in manure than in biosolids samples. The background soil samples showed significantly lower concentration of the above genes compared with manure and biosolids. Lime-stabilized biosolids showed significantly (p < 0.05) lower concentration of antibiotic resistance genes compared with other biosolids treatment methods. Elevated levels of antibiotic resistance genes (Tet-W, Tet-O, and Sul-I) were observed in the amended soil samples after the land application of manure or biosolids (Site A) monitored for a period of about 4 mo. However, at another site (Site B), no significant increase (p > 0.05) in concentration of antibiotic resistance genes was observed after biosolids application on soil. Even though the concentration of antibiotic resistance genes in manure was statistically higher than that in biosolids, when they were applied on land, the contribution to the soil depended on the background soil concentration and the soil characteristics. Further study of multiple soil samples in various locations is needed.  相似文献   

17.
Degradation and mobility of the surfactants linear alkylbenzene sulfonate (LAS) and nonylphenol (NP) were investigated in a lysimeter study using a sandy loam soil and 45-cm soil columns. Anaerobically digested sewage sludge was incorporated in the top-15-cm soil layer to an initial content of 38 mg LAS and 0.56 mg NP kg(-1) dry wt., respectively. Spring barley (Hordeum vulgare L.) was sown onto the columns. The lysimeters were placed outdoors and therefore received natural precipitation, but were also irrigated to a total amount of water equivalent to 700 mm of precipitation. Leachate and soil samples from three soil layers were collected continuously during a growth period of 110 d. Leachate samples and soil extracts were concentrated by solid-phase extraction (SPE) and analyzed using high performance liquid chromatography (HPLC) with fluorescence detection. The concentrations in the top-15-cm soil layer declined to 25 and 45% of the initial contents for LAS and NP, respectively, within the first 10 d of the study. At the end of the study, less than 1% LAS was left, while the NP content was below the detection limit. Assuming first-order degradation kinetics, half-lives of 20 and 37 d were estimated for LAS and NP, respectively. The surfactants were not measured in leachate samples in concentrations above the analytical detection limits of 4.0 and 0.5 microg L(-1) for LAS and NP, respectively. In addition, neither LAS nor NP were measured in concentrations above the detection limits of 150 and 50 microg kg(-1) dry wt., respectively, in soil layers below the 15 cm of sludge incorporation, indicating negligible downward transport of the surfactants in the lysimeters.  相似文献   

18.
The production of water-extractable organic carbon (WEOC) during arctic coastal erosion and permafrost degradation may contribute significantly to C fluxes under warming conditions, but it remains difficult to quantify. A tundra soil collected near Barrow, AK, was selected to evaluate the effects of soil pretreatments (oven drying vs. freeze drying) as well as extraction solutions (pure water vs. seawater) on WEOC yields. Both oven drying and freeze drying significantly increased WEOC release compared with the original moist soil samples; dried samples released, on average, 18% more WEOC than did original moist samples. Similar results were observed for the production of low-molecular-weight dissolved organic C. However, extractable OC released from different soil horizons exhibited differences in specific UV absorption, suggesting differences in WEOC quality. Furthermore, extractable OC yields were significantly less in samples extracted with seawater compared with those extracted with pure water, likely due to the effects of major ions on extractable OC flocculation. Compared with samples from the active horizons, upper permafrost samples released more WEOC, suggesting that continuously frozen samples were more sensitive than samples that had experienced more drying-wetting cycles in nature. Specific UV absorption of seawater-extracted OC was significantly lower than that of OC extracted using pure water, suggesting more aromatic or humic substances were flocculated during seawater extraction. Our results suggest that overestimation of total terrestrial WEOC input to the Arctic Ocean during coastal erosion could occur if estimations were based on WEOC extracted from dried soil samples using pure water.  相似文献   

19.
通过研究改进了土壤有机质含量的测定方法。首先称取适量土壤置于长管消解系统中进行消解,然后采用全自动电位滴定仪进行滴定,直接获得土壤的有机质含量。使用该方法测定的土壤标准样品的有机质含量均在保证值以内,同时对实际样品进行精密度测试,得到相对标准偏差为1.03%。该方法降低了土壤有机质含量检测的实验成本,减少了环境污染,同时提高了实验数据的准确度与精密度,值得推广。  相似文献   

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