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为探究超富集植物藿香蓟(Ageratum conyzoides L.)对镉(Cd)污染农田土壤的修复潜力,通过野外调查,原土盆栽试验和田间试验,测定藿香蓟及其根系土壤Cd含量,计算藿香蓟的富集系数和去除率.结果表明,野外调查中不同铅锌矿区生长的藿香蓟叶片中Cd含量最大值为77. 01 mg·kg~(-1),盆栽试验中,高含量Cd土壤处理(T2)中,地上部Cd积累量达到69. 71mg·kg~(-1),其地上部Cd富集系数为6. 09,在低含量Cd土壤处理(T1)中,藿香蓟对Cd的富集特性与其在高含量条件下对Cd的富集特性一致.藿香蓟对Cd表现出稳定的积累特性.田间试验中,污染区藿香蓟中地上部Cd含量均值为21. 13 mg·kg~(-1),富集系数为6. 93,使用藿香蓟修复Cd污染土壤每亩地种植三茬藿香蓟的去除率为13. 2%~15. 6%.使用超富集植物藿香蓟修复农田Cd污染具有较好的工程应用前景. 相似文献
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阐述了高职院校科技创新能力、结构及其评价指标体系与综合测评方法研究的价值与意义,探讨分析了高职院校科技创新能力的内涵及其基本特征与基本结构,并在此基础上论述了高职院校科技创新能力结构要素之间的相互关系.并以系统学的理论为指导,将高职院校科技创新能力结构要素进行系统深入分析,构建了一套评价高职院校科技创新能力结构的指标体系,并提出了高职院校科技创新能力的综合测评方法.表1,参6. 相似文献
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Pollution due to persistent pesticides is not a regional but a global problem. Organochlorine pesticides are persistent chemicals, stored and accumulated in the tissues of a wide variety of invertebrates and vertebrates including marine species. In the present study the organochlorine residues HCHs, DDTs and PCBs were measured in different trophic groups of birds (scavengers, inland piscivores, coastal piscivores, insectivores, granivores and omnivores) collected from Tamil Nadu Coast, India. The residue accumulation as a function of sex did not depict distinct variation. However, females had lower residue levels than males in terms of their mean weight and feeding habits. A continuous monitoring programme is recommended to establish the studied organisms as indicator species. 相似文献
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Nickel pollution is a serious environmental problem, and its effects may provoke alterations in the ecosystem and in organism of animals and humans. Dermatitis, eczema, and asthma are some illnesses caused by Ni2+ poisoning. In this work, fish fed either Ni2+-enriched pellets or commercial pellets were studied. The amount of Ni2+ in fish were measurements by adsorptive stripping voltammetry (AdSV) with dimethylglyoxime as a complexing agent. The analysis of Ni2+ in fish by AdSV established that its accumulation occurs principally in viscera (670.86 ± 5.82 µg g?1), in the head (697.12 ± 2.77 µg g?1) and in the muscle (405.82 ± 3.26 µg g?1), both after 12 months of experiments. Ni2+ adsorbs preferentially in organs such as the stomach, the intestine, and the kidneys and acts in the central nervous system as well. Tilapia growth and mass were significantly affected by Ni2+ poisoning. From statistical analysis, observed that the results for lengths, weights and metal concentration were different for each sampling at significance level of p < 0.05. The Ni2+ concentration in tilapia was enough to cause the death of tilapias; however, it did not occur because the presence of Zn2+ might act as protective agent of heavy metals. 相似文献
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针对反应位移法计算参数多样性的特点,在设定一个基本工况的基础上,分别对反应位移法中的弹簧系数、地层位移、地层剪力、惯性力4种计算参数以及2种常用的计算模型进行了灵敏度分析,归纳了各个参数的取值方法及误差来源,并对比分析了2种计算模型的计算结果。结果表明,地层剪应力的取值对结构内力的计算结果影响最大,其次为地层变形,弹簧系数的影响最小;在计算模型的选取上,采用结构顶部加弹簧的模型计算的结构内力整体上要比顶部不加弹簧的模型计算的结构内力大,忽略上部土体约束作用,后者的计算结果偏于危险。 相似文献
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通过对胡萝卜鲢鱼丸子的配方和制作工艺试验,得出了鱼肉、肥膘、淀粉、盐分及胡萝卜颗粒的最佳配比,使产品达到营养化、功能化、方便化的目的。 相似文献
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Effects of Karst Forest Degradation on Pulmonate and Prosobranch Land Snail Communities in Sabah, Malaysian Borneo 总被引:1,自引:0,他引:1
MENNO SCHILTHUIZEN‡ THOR-SENG LIEW BERJAYA BIN ELAHAN† ISABELLE LACKMAN-ANCRENAZ† 《Conservation biology》2005,19(3):949-954
Abstract: Limestone (karst) outcrops in Southeast Asia are rich in land snails. Certain groups of land snails, in particular Prosobranchia species, are restricted to limestone and show a high degree of short-range endemism. Karst habitats are, however, seriously degraded by quarrying, logging, agriculture, and burning. The effect of these disturbances on land snail fauna is unknown, so we studied paired primary and secondary forest localities on six separate limestone hills in Sabah, Malaysian Borneo. Land snails were sampled with a standard protocol and identified to species level. More than 16,000 individuals, belonging to 74 species, were recorded. In most sites, snail diversities did not differ between disturbed and undisturbed plots. However, pulmonate snails were significantly more abundant at disturbed localities than prosobranch snails, whereas abundances for both groups were similar at undisturbed sites. Because Prosobranchia contain many site-endemic species, our findings suggest that continued exposure to these disturbances will eventually lead to extinctions in this group. 相似文献
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灌肠生产工艺与常见的质量问题分析 总被引:2,自引:0,他引:2
宾冬梅 《湖南环境生物职业技术学院学报》2002,8(4):279-281
灌肠是我国的大众食品,直接供人民食用,这就要求产品既能保证营养全面,又要安全卫生.本文通过对灌肠生产工艺的研究,从外部形态和内质两方面进行探讨,分析影响灌肠质量的主要因素,为生产高质量灌肠提供重要参数. 相似文献