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181.
Use of ornamental plants for phytoremediation of metal-contaminated soil is a new option. A pot experiment was carried out to assess the effect of application of amendments, i.e., swine manure, salicylic acid (SA) and potassium chloride (KCl), on the growth, uptake and translocation of cadmium (Cd) and zinc (Zn) of ornamental sunflower (Helianthus annuus L.) grown on a contaminated soil. The three amendments increased sunflower height, flower diameter, and biomass. Manure significantly decreased Cd and Zn concentrations in sunflower, and thus decreased the bioaccumulation coeffcient (BCF) of Cd and Zn. However, using of KCl markedly increased Cd concentrations in sunflower and the BCF of Cd. Additionally, both swine manure and KCl application increased Cd and Zn translocation from root to aboveground part. Swine manure and salicylic acid reduced the Cd/Zn ratios in flower of sunflower, while KCl significantly increased the Cd/Zn ratios. Correlation analysis demonstrated that the Cd/Zn ratio in the root of sunflower was affected by K/Na ratio in root and soil available potassium (K) concentration. Ornamental sunflower could be grown as an alternative plant in the Cd- and Zn-contaminated soil with KCl application to get the balance between environmental and economic interests.  相似文献   
182.
To elucidate the mechanisms of tolerance to zinc (Zn) deficiency and Zn toxicity in the root of apple trees, the apple rootstock Malus hupehensis (Pamp.) Rehd seedlings were selected to study the responses of organic acids to Zn homeostasis in roots under low Zn (0 μmol L-1 ), adequate Zn (as control, 4 μmol L-1 ) and toxic Zn (100 μmol L-1 ) treatments. The differences of Zn concentrations and accumulations in the roots were highest, compared with those in the stems and leaves, when apple seedlings were subjected to low and toxic Zn treatments for 1 d. The concentrations and accumulations of oxalic and malic acids in the roots in the low and toxic Zn treatments increased by 20% to 60% compared with those of the control treatment. Significantly negative correlations were found between the total Zn concentrations and the concentrations of oxalic and malic acids in the roots under 1 d of low Zn treatment. However, contrary correlations were found for the toxic Zn treatment. Meanwhile, the maximum influx rates of Zn 2+ under low and toxic Zn treatments increased by 30% and 20%, respectively, compared with the rate of the control treatment. Both Zn deficiency and Zn toxicity increased the concentrations of organic acids in root after short-time Zn treatment, which could resist Zn stress through balanding Zn homeostasis in M. hupehensis Rehd.  相似文献   
183.
A greenhouse experiment was conducted to investigate the immediate effect of application of mono‐ammonium phosphate (MAP), single superphosphate (SSP), and triple superphosphate (TSP) fertilizers containing varying concentrations of Cd on (1) chemical speciation of Cd and Zn in soil solution by chemical‐equilibrium calculations (MINEQL+4.6 model), (2) growth of barley plants, (3) concentrations of Cd, P, and Zn in soil solution and plant tissue, as well as total plant accumulation of Cd, P, and Zn, and (4) monitoring pH and element changes during incubation periods following phosphate application. Results show that, in general, the pH of soil solution increased during the first 40 d of incubation, then declined. Also, at the end of incubation period, pH of soil solution was affected by fertilization source and fertilization rate. The concentration of Cd in soil solution changed with time. Phosphate fertilization (p < 0.05) or fertilizer source (p < 0.05) showed consistent effects. Also, the application of phosphate fertilizers with three rates significantly increased Zn concentrations in soil solution during the first half (0–30 d) of incubation period and then decreased but still more than in the control. In general, application of different sources of phosphate at 100 g kg–1 did not change the dominant forms of Cd in soil solution during all incubation time intervals. Speciation of Zn in the control after 30 d of incubation had changed, in comparison to 10 d of incubation, and the dominant forms were Zn2+, ZnOH+, ZnHCO3, ZnCO3(aq), and Zn(OH)2(aq). Adding phosphate fertilizer significantly increased both shoot and root dry weight compared to control, indicating P was a growth‐limiting factor in the control plants. The Zn concentrations in shoot and root were lower in the TSP‐ and SSP‐fertilizers treatment than those in the MAP and fertilizer treatments at all rates of fertilization. Adding phosphate increased the Cd : Zn and P : Zn ratios in the shoot and root tissue, with the effect being greater with increasing fertilization rate. Phosphate fertilization greatly increased the total accumulation of Cd of barley compared with the control plants (p < 0.001), with the effect being greater with increasing fertilization rate. Source and rate of fertilizers, and their interactions had significant effect (p < 0.05) on Cd accumulation in the whole plant.  相似文献   
184.
锰,锌,铜对肉用仔鸡营养效应的研究   总被引:8,自引:0,他引:8  
选用1日龄ArborAcres(AA)肉用商品一代雏鸡,采用玉主--豆粕型为基础的全价日粮。在全价日粮基础上,研究添加中剂量向量元素锰、锌、铜对肉用仔鸡生产性能、血清指标及组织中向量元素含量的影响。结果表明,采食量和饲料为差很小,添加锰能明显地减少腿病发生率,当日粮中的锰含量为137mg/kg或更高时,腿病发生率从38.5%降至10%以下。铜也能使腿病发生率降低,但不及锰的效果。骨铜含量和骨甸含量  相似文献   
185.
针对河南省气候土壤特点,对锌肥在苏丹草(Sorghumsudanense(Piper))生产中的应用进行了研究。结果表明:苏丹草锌肥的有效范围为400~1000mg/kg,最佳利用浓度为800mg/kg。在最佳利用范围内,LAI提高了9.09%,种子产量提高13.0%。在400~600mg/kg情况下,苏丹草茎秆分别增粗4.19%~7.09%,牧草产量分别提高5.1%~5.4%。  相似文献   
186.
利用Biolog微平板技术,对不同浓度重金属Zn影响下堆料微生物群落多样性进行了研究.结果表明,较低浓度Zn处理(Zn含量为400 mg·kg-1)的堆料升温快,高温持续时间长.微生物群落多样性指数和微生物群落主成分分析(PCA)指标均表明不同浓度重金属处理的堆料微生物群落有明显不同,Zn含量为400 mg· kg-1...  相似文献   
187.
试验结果表明 ,在淮北变性土区 ,施用硫、锌微肥能促进玉米植株的生长发育 ,增强玉米的抗旱能力 ,促进玉米果穗的生长发育和籽粒的灌浆 ,增加玉米籽粒产量  相似文献   
188.
猪粪堆制过程中铅、镉、铜、锌的变化   总被引:4,自引:0,他引:4  
对猪粪在高温好氧堆制过程中铅、镉、铜、锌全量以及相对含量随时间的变化进行了深入研究.结果表明:猪粪中铅、镉、铜、锌总浓度随着堆腐时间的延长呈不断增加趋势;铅、镉、铜、锌的相对含量呈现先增加后下降的趋势;堆腐温度和pH是影响DTPA-Pb、Cd、Cu和Zn的相对含量变化的主要因素.  相似文献   
189.
多胺对锌胁迫下水荷花叶片营养元素吸收的影响   总被引:1,自引:0,他引:1  
[目的]探讨多胺对重金属胁迫下水生植物吸收各种营养元素的影响。[方法]以浮水植物水荷花为试验材料,采用电感藕合等离子体发射光谱法(ICP-MS)测定各种元素含量,研究了外源多胺对锌胁迫下植物叶内锌富集及其他营养元素吸收的影响。[结果]结果表明,100μmol/L的锌处理导致锌在水荷花叶细胞内大量积累,钾、磷和钠渗出量显著上升,铜、锰、镁和钙在细胞中显著累加。外施0.1 mmol/L Spd和Spm均可有效缓解锌诱导。[结论]外源多胺可有效维持锌胁迫下植物体内各种营养元素的平衡。  相似文献   
190.
周龄,饲粮锌水平和锌背景对肉鸡锌吸收利用的影响   总被引:8,自引:1,他引:8  
李杰  许丽 《饲料博览》1996,8(1):8-10
进行3个试验观察半纯合饲粮锌水平、锌背景及周龄和锌的鸡锌吸收利用的影响。采用氨基酸利用率测定方法测定鸡排污物中锌浓度、锌的吸收和锌的真利用率。试验结果表明,排泄物中锌浓度随着饲粮锌水平的提高而呈线性增加,y=61.73+7.62x(4=0.98)。锌的真利用率随饲粮锌水平的提高而显著降低,表明多食入的锌水平的提高而增加。  相似文献   
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