Accumulation of copper in Clarias anguillaris L. and Oreochromis niloticus L.

Clarias anguillaris and Oreochromis niloticus were each exposed to solutions of Analar grade Cu sulphate in static bioassays at a temperature range of 20 to 23.5°C and CaCO₃ hardness of 30 to 44 mg L^?1. Copper accumulation was determined by Atomic Absorption Spectroscopy. The Cu residues in Clarias anguillaris exposed to 0.027, 0.055, and 0.11 mg Cu L^?1. for 8 weeks were 15.7, 21.8, and 31.17 mg g^?1 dry weight, respectively. Oreochromis niloticus exposed to 0.05, 0.1 and 0.2 mg Cu L^?1. accumulated 34.69, 36.09, and 81.03 mg g^?1 dry weight, respectively, over the 8-week period of exposure. The lowest and highest bioconcentration factors (BCF) were 117 and 581 for Clarias anguillaris and, 176 and 694 for Oreochromis niloticus. Copper concentrations in tissues of both species were directly related to the exposure concentrations and the duration of exposure. Increased accumulation towards the last 2 weeks of exposure may be due to impaired capacity of elimination or poor nutritional status.     

Influences of Cadmium and Zinc Interaction and Humic Acid on Metal Accumulation in Ceratophyllum Demersum

Interactions between Zn and Cd on the accumulation of these metals in coontail, Ceratophyllum demersum were studied at different metal concentrations. Plants were grown in nutrient solution containing Cd (0.05–0.25 mg l^?1) and Zn (0.5–5 mgl^?1). High concentrations of Zn caused a significant decrease in Cd accumulation. In general, adding Cd solution decreased Zn accumulation in C. demersum except at the lowest concentration of Zn in which the Zn accumulation was similar to that without Cd. C. demersum could accumulate high concentrations of both Cd and Zn. The influence of humic acid (HA) on Cd and Zn accumulation was also studied. HA had a significant effect on Zn accumulation in plants. 2 mg l^?1 of HA reduced Zn accumulation at 1 mg l^?1 level (from 2,167 to 803 mg kg^?1). Cd uptake by plant tissue, toxicity symptoms and accumulation at 0.25 and 0.5 mg l^?1, were reduced (from 515 to 154 mg kg^?1 and from 816 to 305 mg kg^?1, respectively) by addition of 2 mg l^?1 of HA. Cd uptake reached a maximum on day 9 of treatment, while that of Zn was observed on day 15. Long-term accumulation study revealed that HA reduced toxicity and accumulation of heavy metals.     

Growth and Metal Accumulation of Mycorrhizal Sorghum Exposed to Elevated Copper and Zinc

Arbuscular mycorrhizal fungi (AMF) alter heavy metal acquisition by higher plants and may alter plant response to soil-contaminating heavy metals. Two communities comprised of Glomus intraradices and G. spurcum were investigated for their influence on copper (Cu) and zinc (Zn) resistance of Sorghum bicolor. One community was isolated from a Cu- and Zn-contaminated soil (AMF-C) and one consisted of isolates from non-contaminated soil (AMF-NC). Non-mycorrhizal (NM) sorghum plants were also included. The two community ecotypes differed in their capacity to protect sorghum from Cu and Zn toxicity and exhibited differential metal uptake into hyphae and altered heavy metal uptake by roots and translocation to plant shoots. AMF-C reduced Cu acquisition under elevated Cu conditions, but increased Cu uptake and translocation by sorghum under normal Cu conditions, patterns not exhibited by AMF-NC or NM plants. Hyphae of both fungal ecotypes accumulated high concentrations of Cu under Cu exposure. AMF-C exhibited elevated hyphal Zn accumulation and stimulated Zn uptake and translocation in sorghum plants compared to AMF-NC and NM plants. Differences in metal resistance between fungal treatments and between mycorrhizal and non-mycorrhizal plants were not related to differences in nutrient relations. The enhanced Cu resistance of sorghum and altered patterns of Cu and Zn translocation to shoots facilitated by AMF isolated from the metal-contaminated soil highlight the potential for metal-adapted AMF to increase the phytoremediation potential of mycotrophic plants on metal-contaminated environments.     

Nitrogen,Phosphorus, and Zinc Supply on Seed and Metal Accumulation in Canola Grain

Nutrient supply is important for yield and quality of canola (Brassica napus L.) crop production. A controlled study was conducted to determine the effects of nitrogen (N), phosphorus (P), and zinc (Zn) supply and their interactions on yield and accumulation of four microelements in canola grain. Results showed that seed yield increased 1.45 to 5 times by increasing N and up to 24.4% by increasing P supply, with significant N-by-P interactions. Nitrogen-by-Zn interaction also exhibited large effects on grain metal concentrations, with increased iron (Fe) and copper (Cu) as increasing N supply, and decreased Mn concentration at all N supply levels above 0 N. Zinc concentration was decreased at low N and increased at high N levels compared to 0 N. Increasing P supply reduced grain Fe and Zn accumulations, but had no effect on Mn and Cu. Overall, this study revealed that canola yield and micronutrient accumulations can be improved by appropriate nutrient supply.     

长期施用畜禽养殖废弃物下潮土重金属的累积特征

通过田间试验研究了畜禽养殖废弃物长期施用(2001—2013年)对重金属(Cr、Cu、Zn、Pb、Cd、As)在潮土中累积、形态转化及迁移行为的影响。试验设置畜禽养殖废弃物(猪粪,OM)和化肥氮磷钾(NPK)两个处理,每处理设置3个重复。结果显示,畜禽养殖废弃物的长期施用造成Cu、Zn在OM处理土壤中的含量明显高于NPK处理,并主要累积于耕层土壤(0~20 cm),但总体含量(Cu:38.71 mg/kg;Zn:83.26 mg/kg)较低,对农田生态安全的影响较小。形态分析结果显示,OM处理土壤中DTPA络合态、弱酸结合态和铁锰结合态Cu、Zn、As的含量均显著高于NPK处理,但不同形态Cr、Pb、Cd在两种处理土壤中的差异相对较小。其中,Cr主要以非提取态的形式存在(Cr95%)。外源性Cu易累积于非提取态(52%),而Zn则以弱酸溶解态(40%)和铁锰结合态(60%)为主。畜禽养殖废弃物的农田施用不仅是土壤重金属的重要来源,也是土壤重金属活性提高的重要原因,并造成部分重金属在剖面土壤中发生明显迁移行为,累积于更深层土壤中。     

Characterization of Zinc Oxide Nano Particles and Their Effect on Growth of Maize (Zea mays L.) Plant

In the current literature, the impact of nano-particles (NPs) on growth of higher plants has scantly been reported. An investigation was carried out to study the effect of zinc oxide nano-particles (<100 nm) on growth of maize (Zea mays L.) plant, as one of the major agricultural crops, in a solution culture system. Various concentrations of zinc (Zn) were applied through nano-zinc oxide (ZnO) particles (<100 nm) in suspension form and in ionic form through zinc sulfate (ZnSO₄) salt in Hoagland solution culture. Experimental results showed that nano zinc oxide particles could enhance and maintain the growth of maize plant as well as conventional Zn fertilizer (as ZnSO₄). The plant parameters like plant height, root length, root volume, and dry matter weight were all improved due to application of zinc oxide nano-particle. These findings indicate that plant roots might have the unique mechanism of assimilating nano-Zn and using for its growth and development. Different enzymatic activities were also studied and experimental results revealed that nano-ZnO particles (<100 nm) also governed the enzymatic activity of maize plant. A separate laboratory experiment was also carried out to characterize the zinc oxide nano particle for its size, zeta potential, etc.     

不同施锌方法对小麦含锌量及产量影响的研究

锌是植物体内多种酶的组成成份和活化剂。缺锌影响植物生长和人体健康。在缺锌土壤上施锌肥虽已推广，但用何种方法最好，众说不一。我国有大面积耕地缺锌，研究锌肥及其施用方法是很重要的。本项研究在国内外近期研究的基础上，在缺土壤上使用不同的方法施锌肥，通过对小麦的叶绿素含量、干物重、含氮量、含锌量、17种氨基酸的含量及产量的分析测定，证明土施是最简单、成本最低、效果最好的方法。     

锌对不同基因型玉米幼苗光合特性及锌积累的影响

为探究不同基因型玉米幼苗对锌敏感性差异,以玉米杂交品种天农九(TN9)和信玉9(XY9)为材料,研究不同Zn浓度(0.00、0.01、0.1、1.0、10.0、100μmol·L-1)对叶片光合色素含量、光合作用参数及叶绿素荧光特性的影响。结果表明,玉米最适生长锌浓度为0.1~1μmol·L-1,低锌(0~0.01μmol·L-1)和高锌(10~100μmol·L-1)条件均对不同基因型玉米幼苗的生长产生抑制作用,其中XY9在低锌及高锌胁迫下光合参数及光合色素含量降幅显著,从而导致其植株长势和干物质积累等对锌浓度的动态响应更为强烈,而TN9则对低锌及高锌环境具有较强的适应性。同时,随着锌处理浓度的不断升高,玉米植株中锌含量和积累量均逐渐升高,锌利用率则逐渐降低,其中XY9植株锌积累量低于TN9,而锌利用率则高于TN9;相比于不敏感型品种(TN9),敏感型品种(XY9)对锌的吸收、积累和利用受锌浓度变化的影响更为明显。本研究为植物锌高效利用研究提供理论基础。     

Toxicity of Diflubenzuron and Temephos on Freshwater Fishes: Ecotoxicological Assays with Oreochromis niloticus and Hyphessobrycon eques

Water, Air, & Soil Pollution - Triclosan (TCS) is a potential endocrine-disrupting compound (EDC), which produces an adverse impact on aquatic life and human beings. Wastewater discharge is...     

黑曲霉对潮褐土镉、锌污染的原位固定修复潜力研究

采用温室盆栽试验,研究了在黑曲霉(30582)作用下油菜对潮褐土Cd、Zn复合污染胁迫的耐性及富集特征。结果表明:接入黑曲霉菌液对油菜地上部干重总体上无明显影响,且降低了油菜对土壤Cd、Zn的吸收量。加入黑曲霉菌液后,油菜地上部和地下部Cd含量较对照最高分别降低了31.60%,37.82%;地上部和地下部Zn含量较对照处理最高分别降低了35.12%,35.74%;土壤有效态Cd、Zn含量显著减少,较对照最高分别降低了30.51%,39.64%。综上,黑曲霉有效地降低了污染土壤中Cd、Zn的生物有效性,对土壤中低浓度重金属污染的原位固定表现出较佳的效果,具备应用于修复Cd、Zn污染土壤的潜力。     

Comparative Study on Trace Metal Accumulation in Liver of Mediterranean Deep-Sea Fish and Their Selenium/Mercury Molar Ratios

The objectives of this study were to determine and compare the concentrations of Hg, Cd, Pb, Zn, Cu, Ni and Se in the liver of macrourid fish as Trachyrinchus scabrus, Nezumia sclerorhynchus and Coelorhynchus coelorhynchus from the Mediterranean Sea, Italy. It was also carried out to evaluate the relationship between metal concentration and fish size and to explore selenium/mercury molar ratio. The highest concentrations were in T. scabrus, followed by N. sclerorhynchus and C. coelorhynchus. In all species, any element displayed significant correlation between metal body burden and fish size, except Hg. The mean selenium/mercury ratios were greater than one in all fish species indicating that Se antidotal effect in counteracting Hg occurred. This report represents one of the few surveys providing information on trace metal in deep-sea fish from Mediterranean Sea constituting, thus, an essential baseline work with which future levels may be compared.     

外源生长激素对尼罗罗非鱼生长、骨骼肌纤维增生及肥大的影响

生长激素是影响动物生长发育的最重要内分泌激素,为了探讨外源生长激素对尼罗罗非鱼(Oreochromis niloticus)生长、骨骼肌纤维增生以及肥大的影响,本实验对同一批次尼罗罗非鱼幼鱼进行为期7周的外源重组人生长激素(hGH)肌肉注射,并设置了磷酸盐缓冲液(PBS)注射对照组,每周注射1次,测量体重、体长等表型生长指标,同时,隔两周采集背部肌肉,利用石蜡切片技术分析骨骼肌背侧第一肌节中肌纤维数目与面积的变化.结果显示:(1)注射后第1周起,实验组鱼的体重、体长即高于对照组,但差异不显著(P＞0.05);第5周起,实验组鱼体重显著高于对照组鱼(P＜0.05),第7周起,实验组鱼体长极显著高于对照组鱼(P＜0.01).(2)注射后第1周起,实验组鱼肌纤维数目、总面积均高于对照组鱼,差异不显著(P＞0.05);第5周起,实验组鱼肌纤维的外源性增生和肥大现象极显著(P＜0.01).研究结果表明,外源生长激素对尼罗罗非鱼的表型生长、骨骼肌肌纤维的增生与肥大均有显著促进作用,肌肉生长中以肥大生长更为明显.     

Interactive Effects of Cadmium and Zinc on Carrots: Growth and Biomass Accumulation

ABSTRACT

An experiment was carried out to assess the single and combined effects of cadmium (Cd) and zinc (Zn) on growth and component wise biomass accumulation in carrot (Daucus carota L.) plants, grown under natural field conditions. Carrot plants were raised in field and treated with 10 and 100 μ g mL^{? 1} of Cd, 100 and 300 μ g mL^{? 1} of Zn singly, and in combination through soil drench. A control was also kept without any treatments of Cd and Zn. The impacts of different treatments of Cd and Zn on carrots were evaluated in terms of number of leaves, leaf area, plant length, and component wise biomass accumulation at different plant ages. Growth indices were also calculated to assess the biomass allocation patterns in carrots. The results showed that the above parameters were significantly affected in carrots treated with Cd and Zn singly and in combination as compared to the control as well as plants treated with 100 μ g mL^{? 1} of Zn. The results also showed that treatments of Cd and Zn have significant effects on biomass allocation pattern. This study concludes that growth and biomass accumulation in carrots were significantly influenced by the concentration ratios of Cd and Zn in soil/root/stem/ leaves. It is clear from this study that combined treatments of Cd and Zn have more negative impacts on above parameters as compared to their individual treatments.     

初始含水率及容重影响下红壤水分入渗规律

运用室内模拟土柱试验,研究了初始含水率为7%,11%和15%这3个梯度及容重为1.2,1.3,1.4,1.5g/cm~3这4个梯度对均质红壤水分入渗规律的影响;根据Kostiakov模型和Philip模型对入渗过程进行拟合分析,得出入渗模型参数。试验结果表明:均质红壤水分入渗,入渗率、湿润锋运移速率与时间呈幂函数递减关系,Philip入渗模型较适用;随着时间的推进,土壤逐渐达到饱和,入渗率、湿润锋运移速率的变化也越来越小;入渗率与初始含水率成反比关系,初始含水率越高,入渗率越低;湿润锋运移速率随初始含水率增加而增大;土壤容重越大,入渗率越低,湿润锋运移越慢。     

施用沼液对土壤和玉米重金属累积的影响

为研究沼液不同施用量对土壤和植物重金属累积的影响,以玉米为供试材料,设计小区试验,通过施用不同量的沼液,分析不同沼液施用量对玉米产量的影响、土壤和玉米籽粒中的Cd、Cr、Pb、As、Hg等重金属含量的影响。结果表明:(1)施用沼液及常规化肥处理均能显著增加玉米的产量,增幅为5.56%～13.19%,当沼液施用量控制在5 000～7 000kg/(667m2)的范围内时,玉米能获得较高的产量;(2)玉米种植后,土壤中Cd、Cr、Hg含量与清水对照相比略有增加,而Pb和As变化不大,但均符合GB 15618-1995《国家土壤环境质量二级标准》;(3)随着沼液施用量的增加,玉米籽粒中Cd、Cr、Pb的含量略有增加,而As含量变化不大,Hg未检测出,但均符合食品限量标准(GB 2762-2005)。表明适量沼液的添加能有效实现沼液的资源化利用,同时不会对土壤和植物造成重金属污染风险。     

Metal Accumulation by Woody Species on Contaminated Sites in the North of France

Metal accumulation was investigated in a range of woody species that were planted on Cd-, Zn- and Pb- polluted sites in North of France. The study is unique in that we directly compare a large number of woody species (25). The highest accumulation of Zn and Cd was found in the Salicaceae family members with up to 950 mg Zn kg^?1 dry weight (DW) and 44 mg Cd kg^?1 DW in leaves of Populus tremula × Populus tremuloides. Zn content was positively correlated with Cd content, both in leaves and stems. Pb concentration was generally low and was species-independent. Oak and birch species accumulated more Mn as compared to other woody species. A seasonal variation in metal accumulation could be found. Although soil compositions and metal bioavailabilities differed amongst the experimental sites chosen in this study, variation of metal concentrations within a given species was small. High bioconcentration factors for poplar and willow suggested the high potential of these species over other woody species for metal accumulation. Taken together, these data suggest that poplar and willow species are good candidates for phytoremediation programmes.     

光质和光强对酿酒葡萄光合速率及糖分积累的影响

根据两年的田间试验资料，分析了不同光质和光强对酿酒葡萄光合速率及糖分积累的影响。结果表明：不同光质对酿酒葡萄光合作用有显著影响。在光强较弱的时候，彩色薄膜覆盖有促进葡萄光合作用的效果。光合速率随光强增大而增大，上午各处理间的差异较大，午后这种差异逐渐减小。一定范围内光照强度对葡萄糖分积累有影响，且光强越大糖分积累越高．光照减弱后糖分积累降低。彩色膜覆盖对葡萄糖分积累也有一定影响，多数会使葡萄糖分积累减少。     

Influence of Ammonium and Nitrate Nutrition on Plant Growth and Zinc Accumulation by Indian Mustard

ABSTRACT

The source of nitrogen (N) used in soil fertility practices affects plant growth, nutrient absorption, and the availability of nutrients. Consequently, the potential of plants to extract zinc (Zn) from soils may be increased by controlling the ratio of NH₄ ⁺ to NO₃ ^? to maximize growth and Zn accumulation. The objectives of this research were to determine the effects of Zn supply and different molar ratios of NH₄ ⁺ to NO₃ ^? on growth and Zn accumulation in Indian mustard (Brassica juncea Czern.). In a factorial experiment with solution culture, Indian mustard (accession 182921) was supplied with two concentrations of Zn (0.05 and 4.0 mg L^?1) in combination with six N treatments with different molar percentage ratios of NH₄ ⁺ to NO₃ ^? (0:100, 10:90, 20:80, 30:70, 40:60, and 50:50) for three weeks. Zinc supplied at 0.05 mg Zn L^?1 represented a common concentration of Zn in solution culture, whereas 4.0 mg Zn L^?1 was excessive for plant nutrition. If the supply of Zn in solution was excessive, plants developed symptoms of foliar chlorosis, which became severe if plants were supplied with 80% of N as NO₃ ^?. Supplying high proportions of NO₃ ^? in the nutrient medium stimulated Zn accumulation, whereas increasing proportions of NH₄ ⁺ (up to 50% of the total N) enhanced shoot growth. The pH of nutrient solutions generally decreased with increasing proportion of NH₄ ⁺ in solutions and with increased Zn supply. The Zn phytoextraction potential of Indian mustard was maximized, at about 15 mg Zn plant^?1, if plants received 10% of the total N as NH₄ ⁺ and 90% as NO₃ ^?.     

Effects of Iron and Zinc Fertilizers on the Accumulation of Fe And Zn Ions in Potato Tubers

The aim of this study was the evaluation of the methods to increase the yield of potato and the accumulation of iron (Fe) and zinc (Zn) in response to iron and zinc fertilizers. In these studies, ‘Marfona’ potato (Solanum tuberosum) cultivar was used in a statistical factorial design experiment with three factors: methods of fertilizer application (2 levels of spray and one level by irrigation), kind of fertilizers (iron and zinc) and levels of fertilizer, (0, 1, 2, and 3 mg L^?1). Results showed that iron and zinc fertilizers increased the tubers weight and the tubers number weight^?1 ratio (P < 0.01). Also, results showed that the effects of Fe and Zn fertilizers application in irrigation water was more significant (P < 0.01) than by spray application. In addition, application of Fe and Zn fertilizers resulted in higher concentrations of these ions in the harvested tubers improving their nutritional values.