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1.
蔬菜对土壤镉铜锌富集能力的研究   总被引:11,自引:0,他引:11  
调查了福建部分污染严重地区不同蔬菜对镉、锌、铜的富集能力。结果表明蔬菜对镉的平均富集系数为0.017,锌的平均富集系数为0.116,铜的平均富集系数为0.014。蔬菜对镉的富集系数的品种间差异最大,达315倍,远高于锌和铜的富集系数的品种间差异。茭白、豇豆和莲藕对镉的富集能力较低,可作为镉污染土壤优先选种的蔬菜品种,而青包菜、白包菜、芥菜、空心菜、芋头等对镉的富集系数较高,不宜在镉污染土壤上栽培。  相似文献   

2.
对河南郑州郊县不同种植年限保护地土壤速效氮、磷、钾及重金属铜、锌、镉、铅含量调查表明:随保护地种植年限的增加,速效氮、磷含量有显著的增加,其增加与种植年限呈极显著正相关,速效钾含量增加幅度不大,说明氮、磷、钾肥施用不均衡;重金属铜、锌、铅含量随保护地种植年限的增加有一定的增加,镉含量没有明显的规律性,但这几项重金属含量均比农田含量要高,说明在保护地高强度施肥及人为活动下,引入了重金属;农田及保护地重金属含量较土壤背景值均有一定程度的增加,但未超出国家土壤环境质量标准。  相似文献   

3.
四川平武野生天麻产区的土壤条件   总被引:1,自引:0,他引:1  
研究了平武野生天麻(Gastronia elata)产区土壤类型、土壤肥力、土壤及天麻中微量元素组成特征。该区土壤以粗骨性壤土为主,为弱酸性条件,土壤的有机质、全氮、速效磷、速效钾、速效锌、速效锰、速效铜等含量较高,土壤肥力优良。土壤中重金属元素Hg、As、Pb、Cr含量符合土壤一级质量标准,Cd符合二级质量标准,综合指标优于中药材GAP生产要求的土壤二级质量标准,是发展中药材生产的良好基地。天麻对重金属元素汞有较强的富集作用,对铜、锌具较强的主动吸收作用。  相似文献   

4.
辽河干流坝间耕地土壤重金属污染特征研究   总被引:1,自引:0,他引:1  
通过对辽河干流坝间10个断面耕地土壤0~5 cm、5~15 cm、15~30 cm沉积层重金属铜、镉、锌、铅含量测定,评价了该区土壤重金属污染程度,并采用地质累积指数法评价单一重金属污染状况与潜在生态危害指数,综合评价重金属生态危害程度。研究结果表明,该区土壤铜、铅、锌与镉含量均值分别为32.42 mg?kg~(-1)、38.23 mg?kg~(-1)、47.35 mg?kg~(-1)和1.625 mg?kg~(-1);铅、锌含量均值在达牛渡口最大,分别为55.54 mg?kg~(-1)和80.51 mg?kg~(-1);铜、镉含量均值在通江口处最大,分别为50.24 mg?kg~(-1)和3.103 mg?kg~(-1)。除镉外,铅、铜、锌含量各断面不同深度浓度均低于全国土壤环境质量Ⅱ级标准,镉含量均值是全国土壤环境质量Ⅱ级标准的1.70倍,最大值为3.402 mg?kg~(-1);辽河大桥上游干流镉含量是下游镉含量的6.47倍。镉的地质累积指数值在坝间均显污染,其中,辽河大桥以上各断面显强污染。通江口至毓宝台特大桥重金属潜在生态风险指数值最强。各断面镉对多种金属潜在生态风险指数值的贡献达78.77%~98.23%,贡献率与潜在生态危害指数(RI)呈正相关。多种重金属潜在生态风险指数值变化趋势与镉地质积累指数分布趋势相同,最大值出现于通江口断面。  相似文献   

5.
采用野外调查与室内实验分析相结合的方法,以哈尔滨市街道广场绿地、单位附属绿地、苗圃生产绿地的“乔灌草密林、乔灌草疏林、灌木密林”植物群落为研究对象,综合评价不同植物群落土壤的重金属Zn、Cu、Pb含量与污染程度,对比分析不同植物群落的重金属修复效应及树木含水量、全氮、全磷含量与土壤重金属富集的相关性.结果表明:土壤重金属修复能力为乔灌草密林>灌木密林>乔灌草疏林;植物根系重金属富集能力最强,其中小根对锌、铜富集能力较强,大根、中根对铅富集能力较强;树种富集重金属能力显著不同,梓树、黄檗对铜富集能力较强,铺地柏、红皮云杉、小叶丁香对铅富集能力较强,紫丁香、胡桃楸对锌富集能力较强;树木富集铜和锌的能力与其叶片含水量、叶片全磷含量密切相关.为了有效修复土壤重金属污染,提出了优先选用耐重金属植物、努力提高乔灌木小根数量、科学营造乔灌草复层群落等种植对策.  相似文献   

6.
在2004年土壤调查数据的基础上,参照1982年土壤普查的资料,分析了张家港市土壤中有效铜和有效锌的时空变化趋势,并探讨了土壤性质、农业生产管理措施及环境污染等因素对它们的影响。研究结果表明:二十几年来,该地区土壤中有效铜和有效锌含量有了显著增加。在空间上,虽然土壤有效性铜和锌在水耕人为土高于北部的潮湿雏形土的格局没有改变,但在局部地区积聚的现象较为明显。这些时空变异的特征是由于二十多年来该地区农业生产管理措施的改变,工业发展等的外在因素,通过土壤性质发生改变(pH降低、有机质含量增加)而造成的。同时,工业、农业和城市活动带来的废弃物进入土壤中,也可导致土壤有效铜和锌含量增加。土壤有效铜和锌的时空演变,导致了研究区出现了铜过量的土壤,因此今后注意土壤铜过量对作物产生的危害。而土壤有效锌虽然有所增加,但大部分土壤仍处于较低或缺乏的状态,农业生产中应注意恰当施用锌肥,以提高作物产量,改善作物品质。  相似文献   

7.
随着新时代农业的发展,蔬菜大棚在农业产值方面取得了可观的收益,但封闭式大棚内的土壤因使用周期、化肥农药等原因污染越来越严重,为蔬菜食品安全和人类身体健康带来了隐患。基于此,以山西省太谷县周边蔬菜大棚为主要调查对象,采集20多个不同设施大棚中土壤和植物样品,并对其进行镉铜锌重金属元素的含量测定,通过重金属含量、植物富集系数、土壤去除率等评定土壤和农作物现状,比较出不同轮作方式下能够修复和控制土壤中重金属污染的最优轮作方式。  相似文献   

8.
双城市土壤重金属空间分异及影响因子分析   总被引:13,自引:1,他引:13  
采用地理信息系统(GIS)和地统计学相结合的方法,研究了黑龙江省双城市的土壤全量铜、锌、铅、镍、镉5种重金属元素的空间分异规律及其影响因子。结果表明:研究区土壤锌、镍、镉具有强烈的空间相关性,表明这3种元素受土壤内在属性影响较大;而铜、铅具有中等强度的空间相关性,表明这2种元素由土壤内在属性和人为因素共同起作用。镉、铅、铜较锌、镍的变程小,说明前3种重金属元素含量可能主要受到较小尺度因子的影响。研究区土壤各重金属元素空间分异规律如下:铜和镍呈东高西低的趋势,铅呈南高北低的趋势,而锌和镉分别表现为块状分布和岛状分布的特点。影响重金属元素空间分布的影响因子主要有自然因素(土壤类型、高程、土壤理化性质等)和人为因素(乡镇、道路、各种工厂等)。  相似文献   

9.
采用野外调查与室内分析相结合的方法,对四川平武野生天麻产区的自然地理、气候、植被、土壤营养成分、土壤及天麻中微量元素含量等进行了研究。研究表明平武野生天麻主要分布于海拔800-1900m范围,该区气候温和、降雨充沛,林木以青冈树为主,草本植物以蕨类为主,成土母质为志留系千枚岩。野生天麻多生长于壤土中,土壤为弱酸性,有机质含量丰富,土壤中速效氮、速效钾含量中等,速效磷较缺乏,土壤有效铜、有效锌和活性锰含量较高,未遭受到重金属污染。天麻对铜、锌具有选择性吸收作用。  相似文献   

10.
县域耕地土壤锌含量的协同克里格插值及采样数量优化   总被引:10,自引:2,他引:8  
耕地土壤锌含量的空间分布和适宜的采样数量研究,为农产品产地评价和认证、土壤环境质量调查提供帮助。以土壤有机质、pH、全氮、碱解氮、有效铁、有效铜、有效锰、高程数据为辅助变量,采用协同克里格插值方法,对吉林省舒兰市耕地土壤锌含量进行了插值精度分析,并对不同样点数量下协同克里格法在县域尺度耕地土壤锌含量空间分布研究中的适用性进行了评价。结果表明,相同采样数量下,土壤锌协同克里格法的均方根误差比普通克里格法低,拟合效果更好;辅助因子对土壤锌协同克里格插值的影响效果大小为:全氮>有效锰>高程>有效铁>碱解氮>pH>有机质>有效铜;当高程和有效铜作为辅助因子时,土壤采样数量可以减少20%,土壤锌协同克里格插值仍能满足精度要求。协同克里格作为一种更为精确和经济的空间插值方法,可为县域尺度耕地土壤重金属含量的空间分布研究提供更多的信息和帮助  相似文献   

11.
Current UK legislation permits the application of sewage sludge to agricultural land provided concentrations of heavy metals in soil do not increase above maximum permissible limits. However, even within the defined limits, we do not know how an increase in soil heavy metal concentrations is likely to affect biological diversity and activity. Here we report on the effects of sewage sludge addition, including sludge rich in the metals cadmium, copper and zinc, on soil fungal community composition using both an rDNA and rRNA DGGE approach. Sewage sludge addition altered fungal ITS-DGGE banding patterns, however, there were no additional effects of an increase in soil heavy metal concentrations. Similar results were obtained for the full range of copper rich sludge treatments even when copper concentrations were well above the maximum permissible limits. Our data therefore demonstrate that although an increase in soil organic matter content alters soil fungal community diversity and composition, increasing soil concentrations of cadmium, copper and zinc up to current legislative limits had little additional effect regardless of whether rRNA or rDNA was analysed. This suggests that current UK limits for these three heavy metals are within a concentration range that the dominant soil fungi at this field site can tolerate.  相似文献   

12.
Soil and plant samples (Lolio-Cynosuretum) were taken from four different locations in Hesse, Germany. Different doses of nitrogen, phosphorus, and potassium fertilizers were applied to verify metal input due to fertilization. Metal concentrations in plants increased due to mineral fertilization. Detected plant cadmium (Cd), copper (Cu), manganese (Mn), lead (Pb), and zinc (Zn) concentrations in non-fertilized plots were 0.04, 4.13, 106.5, 0.57, and 23.0 mg kg?1 and in long-term NPK-amended plots they were 0.31, 15.3, 524.9, 3.49, and 60.0 mg kg?1, respectively. Transfer factor (TF) was observed to decrease in the order of Cd>Cu>Zn>Mn>Pb. The results of regression analysis showed that organic carbon (Corg) content, effective-cation exchange capacity (CECeff), and bioavailable metal content are the most important predictors for plant metal uptake. This study confirmed that plant metal uptake was not only highly affected by the soil metal content but also influenced by soil properties.  相似文献   

13.
为了解黄土高原苹果园肥力状况,在大量调查研究的基础上,结合GIS采集苹果主产区黄陵县的304个苹果园的土壤和叶片样品,测定分析土壤有机质、全氮、速效氮、p H、速效磷、速效钾、CEC及有效铁、锰、铜、锌的含量和叶片全氮、全磷、全钾及微量元素的含量,并根据土壤和叶片相应的评价标准对其进行丰缺评价。结果表明:该地区土壤有机质含量很低,72%的果园未达到绿色食品土壤肥力指标的正常值含量;土壤和叶片氮含量较低,磷和钾含量较高,其需肥顺序为氮钾磷;该地区微量元素含量较低,在以后的生产中需多施微肥。通过对土壤养分进行相关性分析,得知土壤有机质含量的提升有利于土壤中大量元素的有效养分增加。从土壤和叶片养分间的相关性分析得知,仅土壤钾和叶片钾呈负相关,而其余元素全部呈正相关,由此得出通过提升土壤中某元素的含量可以使得叶片中相应元素含量相应增加,而元素钾无此效应。  相似文献   

14.
Critical loads of acidity have been used by the UNECE Convention on Long Range Transboundary Air Pollution for the development of protocols to control the emissions of acidifying pollutants. Since soil acidity has an effect on the mobilisation of heavy metals in the environment, it is important to understand the relationships between acidity and heavy metal pollution. This paper examines the relationships between soil acidification and heavy metal (cadmium, copper, lead and zinc) concentrations in topsoils and in stream sediments. It makes use of published heavy metal data and two indices of acidification: soil pH and soil acidity critical loads. For cadmium and zinc, a general increase in the ratio of stream sediment to toposil metal concentrations is seen with a decrease in soil pH and soil acidity critical loads. This demonstrates that where soils are more acidic and acid sensitive the metal concentration in the stream sediments is greater relative to that in the topsoil, suggesting mobilisation of these metals under acid conditions. Results for copper are similar but the relationship weaker. However, for lead the ratios tend to decrease with a decrease in pH and critical loads suggesting that where soils are more acid, lead remains in the soil rather than being mobilised into streams and precipitating onto stream sediments. This reflects the association between soil lead concentrations and soil organic matter content, which tends to be greater in acidic, peaty soils.  相似文献   

15.
Abstract

The accumulation of heavy metals in plants is related to concentrations andchemical fractions of the metals in soils. Understanding chemical fractions and availabilities of the metals in soils is necessary for management of the soils. In this study, the concentrations of copper (Cu), cadmium (Cd), lead (Pb), and zinc (Zn) in tea leaves were compared with the total and extractable contents of these heavy metals in 32 surface soil samples collected from different tea plantations in Zhejiang province, China. The five chemical fractions (exchangeable, carbonate‐bound, organic matter‐bound, oxides‐bound, and residual forms) of the metals in the soils were characterized. Five different extraction methods were also used to extract soil labile metals. Total heavy metal contents of the soils ranged from 17.0 to 84.0 mgCukg?1, 0.03 to 1.09 mg Cd kg?1, 3.43 to 31.2 mg Pb kg?1, and 31.0 to 132.0 mg Zn kg?1. The concentrations of exchangeable and carbonate‐bound fractions of the metals depended mainly on the pH, and those of organic matter‐bound, oxides‐bound, and residual forms of the metals were clearly controlled by their total concentrations in the soils. Extractable fractions may be preferable to total metal content as a predictor of bioconcentrations of the metals in both old and mature tea leaves. The metals in the tea leaves appeared to be mostly from the exchangeable fractions. The amount of available metals extracted by 0.01 mol L?1 CaCl2, NH4OAc, and DTPA‐TEA is appropriate extractants for the prediction of metals uptake into tea plants. The results indicate that long‐term plantation of tea can cause sol acidification and elevated concentrations of bioavailable heavy metals in the soil and, hence, aggravate the risk of heavy metals to tea plants.  相似文献   

16.
Spring wheat was grown in soils near a non-ferrous metals mining and smelting base in Baiyin city, Gansu province, P.R. China. The area studied is 501 km2. Some of the croplandshad been contaminated by heavy metals mainly through wastewaterirrigation or aerial deposition. The soil samples were analyzedfor pH, organic matter and available phosphorous (P); also fortotal cadmium (Cd), lead (Pb), copper (Cu) and zinc (Zn) contents. Spring wheat grains were also analyzed for heavy metals. The results were interpreted using multiple linear correlation and stepwise regression analyses. The increment oftotal soil contents of selected heavy metals could enhance grain Cd accumulation, and the increment of total Zn content of soil could lower the grain Pb accumulation. The correlationswere markedly increased by including other soil properties forgrain Cd and Pb. Stepwise regression analyses indicated that the effect of soil pH and available P on the uptake of grain Cd were greater than that of the other total soil contents ofheavy metals. Grain Cd and Pb could be reliably predicted bythe total soil contents of Cd and Pb while the uptake of grainZn and Cu were not satisfactorily predicted.  相似文献   

17.
  目的  研究油葵和苦荬菜根际土壤固、液相对镉(Cd)和锌(Zn)的活化机制,比较两种植物在轻、中度复合污染农田的修复潜力。  方法  通过大田试验种油葵和苦荬菜,测定成熟期土壤的pH值、有机酸、重金属总量及其生物有效性;测定土壤溶液中的溶解性有机质(DOM)、主要离子、水溶态重金属及其形态分布;测定植物各部位中重金属的浓度及形态,通过计算重金属在植物中的富集系数(BCF)和转运系数(TF),比较两种植物对土壤重金属污染的修复潜力。  结果  油葵和苦荬菜根系分泌的低分子有机酸均使根际土壤pH值下降明显,显著低于非根际土壤(P < 0.05);苦荬菜根际土中低分子有机酸及DOM的浓度显著高于油葵根际土(P < 0.05)。两种植物根际土壤溶液中的Cd以离子态和DOM结合态为主,Zn以离子态为主;两种植物根际土壤中有效态的Cd差异不显著,油葵根际有效态Zn显著高于苦荬菜;两种植物根际土壤的Zn和Cd有效态与土壤溶液中Cd-DOM和Zn-DOM呈显著相关。苦荬菜根对重金属的富集能力较强,但油葵地上部分能吸收转运更多的Cd和Zn,并在叶中以毒性较低的不溶性磷酸盐结合态和草酸结合态富集。  结论  两种植物根际分泌的有机酸可以增加根际土壤中的Cd-DOM和Zn-DOM的浓度,提高土壤中的Cd和Zn的有效性,苦荬菜根际对重金属有较强的活化能力,但油葵地上部分对Cd和Zn的吸收转运能力更强。两种植物都具有较强的土壤重金属修复潜力,但从经济角度出发,油葵更适合现阶段我国农田重金属污染的修复。  相似文献   

18.
施肥对灌漠土作物产量、土壤肥力与重金属含量的影响   总被引:1,自引:0,他引:1  
有机物还田是提升土壤肥力的主要措施,但也存在造成土壤金属污染的潜在风险。为查明不同有机物还田对土壤质量及作物产量的影响,本文通过长期定位试验,研究了无肥对照、常规施化肥(氮磷配施)以及70%常规化肥与牛粪、沼渣、污泥、鸡粪、菌渣和猪粪配施对土壤理化性状、有机碳和氮的固存率、氮磷钾活化系数、作物产量及重金属含量的影响。结果表明:牛粪、沼渣、污泥、菌渣、鸡粪和猪粪与70%化肥配施虽作物产量与常规施化肥相似,但6种有机物处理土壤有机质、全氮和碱解氮含量都较常规施化肥处理显著增加,污泥、鸡粪和猪粪处理土壤全磷与速效磷含量较常规施化肥处理显著增加,而且牛粪、沼渣、鸡粪和猪粪处理的速效钾、土壤磷活化系数和土壤钾活化系数较常规施化肥处理也显著提升。牛粪、沼渣、污泥、菌渣、鸡粪和猪粪处理土壤有机碳固存率为36.42%~71.61%,较常规施化肥处理都显著提高;而其氮固存率为6.47%~49.44%,仅有菌渣处理与常规施化肥处理差异不显著,而其他处理较常规施化肥处理显著增加。长期施鸡粪和菌渣处理的土壤铜含量较常规施化肥处理显著增加,增加量分别为4.17mg·kg~(-1)和14.2mg·kg~(-1);而污泥、鸡粪和菌渣处理的土壤锌含量较常规施化肥处理显著增加,增加量分别为13.53 mg·kg~(-1)、22.60 mg·kg~(-1)和49.73mg·kg~(-1)。综上,等有机质(4 500kg×hm~(-2))的牛粪、沼渣、污泥、菌渣、鸡粪和猪粪可替代30%氮磷肥,作物产量不受影响;不同有机物培肥土壤效果为污泥、鸡粪和猪粪优于牛粪和沼渣,而沼渣的培肥效果略差。为保证土壤环境质量稳定不恶化,种植小麦时有机物铜和锌的年携入量应分别低于53.01g×hm~(-2)和221.30 g×hm~(-2),而种植玉米时应分别低于153.40 g×hm~(-2)和347.04 g×hm~(-2)。  相似文献   

19.
Lacey  E. M.  King  J. W.  Quinn  J. G.  Mecray  E. L.  Appleby  P. G.  Hunt  A. S. 《Water, air, and soil pollution》2001,126(1-2):97-120
Surface samples and cores were collected in 1993 fromthe Burlington Harbor region of Lake Champlain. Sediment samples were analyzed for trace metals(cadmium, copper, lead, nickel, silver and zinc),simultaneously extracted metal/acid volatile sulfide(SEM-AVS), grain size, nutrients (carbon and nitrogen)and organic contaminants (polycyclic aromatichydrocarbons (PAHs) and polychlorinated biphenyls(PCBs)). The concentrations of cadmium, copper,silver and zinc from the partial sediment digestion ofthe surface samples correlated well with each other(r 2>0.60) indicating that either a commonprocess, or group of processes determined the sedimentconcentrations of these metals. In an analysis of thespatial distribution of the trace metals and PAHs,high surficial concentrations were present in thesouthern portion of the Harbor. The trace metal trendwas strengthened when the concentrations werenormalized by grain size. A sewage treatment plantoutfall discharge was present in the southeasternportion of the Harbor at the time of this study and isthe major source of trace metal and PAH contamination. Evaluation of sediment cores provides a proxy recordof historical trace metal and organic inputs. Thepeak accumulation rate for copper, cadmium, lead, andzinc was in the late 1960s and the peak silveraccumulation rate was later. The greatestaccumulation of trace metals occurred in the late1960s after discharges from the STP began. Subsequentdeclines in trace metal concentrations may beattributed to increased water and air regulations. The potential toxicity of trace metals and organiccontaminants was predicted by comparing contaminantconcentrations to benchmark concentrations andpotential trace metal bioavailability was predictedwith SEM-AVS results. Surface sample results indicate lead,silver, ΣPAHs and ΣPCBs are potentially toxicand/or bioavailable. These predictions were supportedby studies of biota in the Burlington Harborwatershed. There is a clear trend of decreasing PAHand trace metal contaminant concentrations withdistance from the STP outfall.  相似文献   

20.
This paper presents the results of determining the pseudo-total concentration of five heavy metals in the soil on which the destruction of ammunition, mines, and explosive devices is carried out by the method of open detonation. In the analyzed area, the concentrations of cadmium, lead, nickel, copper, and zinc were determined, while from the physical properties of the soil were determined the granulometric composition and the pH. The aim of the study is to determine the origin and total load on heavy metals and, based on that, to assess the dangers and impact of the site in terms of the soil pollution by heavy metals. In accordance with the regulations of Bosnia and Herzegovina, the results of the soil testing showed a significant load of copper (up to seven times) and cadmium (up to six times), and exceeding the allowed values for nickel and zinc in some places. Lead was the only metal whose concentration was within the maximum allowed and according to that the soil was classified as unpolluted. A sample of soil from the edge of the pit is the only sample in which all heavy metals, except Ni, were within the maximum allowable concentration. In regard to the concentration of the examined metals, the soil of the pit is classified as medium polluted from the aspect of copper, cadmium, and nickel and highly contaminated with zinc. The concentrations of copper and zinc in the examination area correspond to contaminated soil that represents ecological risk, which requires soil remediation.  相似文献   

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