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排序方式: 共有241条查询结果,搜索用时 15 毫秒
101.
Abstract Four sprays of 0.05 ana 0.10% phosalone were given on chilli (Capsicum annuum Linn.) crop at an interval of 15 days starting from 21 days after transplanting. Residues were determined in the green chilli fruits by GLC after cleanup of extract on multiband thin‐layer plate. The half‐lives of residues were 1.55 and 1.68 days on chilli fruits from the crop treated with four sprays of 0.05 and 0.10% phosalone respectively. The time required to reach the tolerance limit of 1 ppm after last spray with 0.05 and 0.10 % emulsion was 4.75 and 7.62 days respectively. Washing of fruits under tap water was found effective in bringing down the level of phosalone residues by 21.64 to 75.11 %. 相似文献
102.
The tolerance of terrestrial ecosystems of the Kola Peninsula to atmospheric deposition of acid-forming sulfur compounds and the risk of their excess input into these ecosystems have been assessed on the basis of the critical load concept. The most sensitive ecosystems (critical sulfur load <400 equiv/ha per year) occupy 58% of the total area of the peninsula. These are mainly pine, spruce, and birch forests (including open and crooked birch forests) growing on podzols formed on sandy boulder-pebble glacial deposits. The zones of ecological risk cover the northwestern and central parts of the peninsula near the Pechenganikel and Severonikel combined works (20% of the total area). 相似文献
103.
铜胁迫对3种草本植物生长和重金属积累的影响 总被引:1,自引:0,他引:1
采用盆栽试验,研究了不同浓度Cu胁迫对3种草本植物弯叶画眉草、象草和苏丹草生物量、根系耐性指数、Cu积累量、富集系数、转运系数的影响。结果表明,弯叶画眉草和象草生长随着Cu胁迫浓度的升高呈现"上升-下降"趋势,胁迫浓度低于100 mg·kg~(-1)时促进生长;苏丹草生长随着Cu胁迫浓度的增加而下降;弯叶画眉草、象草和苏丹草的Cu耐性指数分别是130.63、149.15和75.81。3种植物对重金属Cu均以根系积累为主,积累量随着Cu处理浓度的增加显著升高;对Cu的吸收和富集能力为象草苏丹草弯叶画眉草,Cu从根系转运到地上部的能力为弯叶画眉草象草苏丹草,转运系数均小于1。可见,象草耐性较强,可用于Cu污染土壤植物修复;弯叶画眉草转运能力较强,可用于Cu污染土壤生物净化。 相似文献
104.
105.
Cecilia S. Carranza Carla L. Barberis Stella M. Chiacchiera Ana María Dalcero Carina E. Magnoli 《Journal of environmental science and health. Part. B》2016,51(1):35-43
Glyphosate-based herbicides are extensively used in Argentina's agricultural system to control undesirable weeds. This study was conducted to evaluate the culturable mycobiota [colony forming units (CFU) g?1 and frequency of fungal genera or species] from an agricultural field exposed to pesticides. In addition, we evaluated the tolerance of A. oryzae and nontoxigenic A. flavus strains to high concentrations (100 to 500 mM – 17,000 to 84,500 ppm) of a glyphosate commercial formulation. The analysis of the mycobiota showed that the frequency of the main fungal genera varied according to the analyzed sampling period. Aspergillus spp. or Aspergillus section Flavi strains were isolated from 20 to 100% of the soil samples. Sterilia spp. were also observed throughout the sampling (50 to 100%). Aspergillus section Flavi tolerance assays showed that all of the tested strains were able to develop at the highest glyphosate concentration tested regardless of the water availability conditions. In general, significant reductions in growth rates were observed with increasing concentrations of the herbicide. However, a complete inhibition of fungal growth was not observed with the concentrations assayed. This study contributes to the knowledge of culturable mycobiota from agricultural soils exposed to pesticides and provides evidence on the effective growth ability of A. oryzae and nontoxigenic A. flavus strains exposed to high glyphosate concentrations in vitro. 相似文献
106.
紫羊茅抗铜和敏感品种在发育早期对铜离子反应的生理差异 总被引:8,自引:0,他引:8
紫羊茅(Festucarubra)抗铜品种Merlin和敏感品种559种子在水中吸胀5d后长出的幼苗在一般培养液中分别培养了0、2、4、6、8和10d(分别称为D0、D2、D4、D6、D8和D10)后再置于ρ(Cu2+)=5mg/L的相同培养液中,其中约一半培养至d20,其余至d27.结果与同龄的幼苗相比,MerlinD6在27d和20d的根中均有最高的干物质含量和最大的叶绿素浓度;在27d苗的根中铜积累了最少;而MerlinD6的苗在各个抗性处理组中最高在从20d至27d的培养期间,MerlinD6地上部分的干物质增加最多,而根中则减少最多,叶绿素含量也减少最多,在根中积累的铜也最少;可是在敏感的S59中则没有这种特殊现象,这些现象暗示,即使是在抗性品种的Merlin中,在其不同的生长时期经铜处理,也表现出不同的抗性,并可能有一个抗性最大的生长期。 相似文献
107.
Mechanisms of copper tolerance by Armeria maritima in Dolfrwyong Bog,north Wales--initial studies 总被引:1,自引:0,他引:1
Preliminary field studies were carried out at Dolfrwynog Bog in July 2000. Replicate samples of water, Armeria maritima plants and the soils adhering to its roots were collected and analysed for copper. Concentrations of up to 6486 mg kg–1 of copper in the soils were recorded. Accumulation of copper by the plant as expressed by concentration factors (CF) show that it is acting mainly as a copper excluder. Of the copper that is taken up, most of it is retained within the roots with very little being transported to the shoots of the plant. Moreover, a further possible mechanism of tolerance is exhibited by the excretion of copper through its decaying leaves. Towards the use of in vitro cultures to study the copper tolerance mechanisms in A. maritima a micropropagation protocol has been developed. The ex vitro plants have been rooted and established in compost. 相似文献
108.
阊江河1~6级支流大型底栖无脊椎动物取食功能团演变特征 总被引:2,自引:2,他引:2
河流连续性概念(rivercontinuumconcept,RCC)将自然河流生态系统视为物理和生物的连续体,河流物理环境的梯度变化决定了生物的演变格局.为探索自然河流系统受人类干扰后大型底栖无脊椎动物的演变规律,作者于2002年5月、8月、11月对安徽省祁门县阊江河1~6级支流的大型底栖无脊椎动物进行了调查,共获7纲57科101属119种,计8813头,并详细记载了各级支流样点的栖境特点.运用“河流连续性概念”理论分析结果表明该河1~6级支流大型底栖无脊椎动物各取食功能团演变趋势符合该理论,但上游至下游的生物区系演替程度明显小于未受干扰的自然河流,1~6级支流各功能团的分布(P/%)梯度变化趋于平缓,仅捕食者数量分布与理论预测模式比较接近.各级支流相同取食功能团的优势类群各异,其种类的耐污能力随河流级别的增加总体呈上升趋势.同级支流各取食功能团的分布(P/%)比例存在季节性差异.图2表3参15 相似文献
109.
从冀东油田钻井废液中筛选分离出耐盐石油降解菌Virgibacillus sp.(简称SJ菌),其在高含盐条件下对石油具有较好的降解效果,高达56.12%左右。考察了pH值、盐度、不同N和P形态等因素对SJ菌降解石油效果的影响。结果表明:SJ菌有较宽的pH值适应范围(pH值为6~10)和较好的耐盐能力(0.5%~20%),在pH值为9及NaCl质量浓度为5%时对石油类降解效果最好,其最佳利用N源和P源分别为(NH2)2CO和KH2PO4,该研究为油田高含盐含油废液处理提供了一条新途径。 相似文献
110.
The goal of the present study was to compare the different survival of Oxya chinensis exposed to chromium(Ⅵ) among allozyme genotypes to gain a better understanding of the relationship between the genetic variations and environmental disturbance. This study analyzed the occurrence of genotypes in O. chinensis population exposed to Cr(Ⅵ). O. chinensis samples were collected at Yuanping, Shanxi Province, China and used in acute toxicity tests. Specimens were assigned to Cr(Ⅵ) exposure (LD50: 291.0 mg/kg) for ... 相似文献