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浅谈水利工程施工阶段的监理 总被引：1，自引：0，他引：1
高俊芳 《山西水土保持科技》2008,(4)
工程建设监理是指监理单位受项目法人委托,依据国家有关工程建设的法律法规、标准规范、规程制度以及批准的项目建设文件、建设工程合同与建设监理合同,对工程建设实行的监督管理。重点介绍了水利工程施工阶段监理机构的组建、监理人员的素质要求与质量控制、投资控制、进度控制方法。 相似文献
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王海燕 《山西水土保持科技》2017,(2):40-41
自推行建设工程监理制度化以来,监理为保证工程质量、控制工程进度和投资发挥了重大作用。但是,由于监理企业本身内在的缺陷以及一些客观外在条件,制约了监理工作效益的正常发挥。根据本人在中小型水利工程的监理实践,归纳总结了一些对水利工程监理的粗浅认识。 相似文献
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白利峰 《水土保持应用技术》2019,(4):52-54
水土保持监理工作是对水利工程建设领域监理工作的细化,虽然水保工程相对于其他水利工程级别低、规模较小,但同样存在施工质量与安全问题。为此,作者简要分析了水保工程施工阶段监理质量控制的重要性,并结合工程实际,总结了水保工程施工阶段加强监理质量控制的方法。 相似文献
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黄延高速公路水土保持生态工程监理实践 总被引：2，自引：0，他引：2
水土保持生态工程监理作为一项专业技术监理引入到高速公路建设中,标志着高速公路建设监理体系日趋完善,其专业的特殊性要求在高速公路工程监理的基本框架内增加与之相适应的监理程序和方法,并贯穿于规划设计阶段、施工阶段和竣工验收阶段的全过程,确保建设项目水土保持方案“三同时”制度得到落实,通过质量控制、进度控制、投资控制等手段,加强监督和管理,提高工作效率。 相似文献
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我国工程建设监理制度从1988年开始试点,至今已走过20个年头,本文介绍了水保工程项目施工阶段的监理的体会,项目监理机构组建、监理工程师质量控制的任务、程序和方法、投资控制、进度控制,监理工作面临的问题及解决方法,对开展监理工作有一定的意义。 相似文献
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青海省小流域坝系建设监理成效与亟待解决的问题 总被引：1，自引：1，他引：0
青海省在小流域坝系工程建设中,实行了项目法人制、招标投标制和建设监理制三项管理制度,保证了工程按照年度建设计划任务、施工技术规范和设计要求进行施工。西安黄河工程监理公司青海省项目监理部按照施工合同和监理合同有关条款约定,采取旁站监理与巡视监理相结合的方式,监督、检查、管理淤地坝工程施工进度、质量,有效地控制了投资,已完成工程达到技术规范、质量标准和设计要求。根据坝系工程施工监理实践,提出了淤地坝建设过程中存在的设计与施工问题及解决的建议。 相似文献
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开发建设项目水土保持专项监理中存在的问题及对策 总被引：2，自引：2，他引：0
简要分析了开发建设项目水土保持专项监理中存在的问题,结合工程实际提出了解决问题的对策:一是明确监理对象,细化监理内容;二是加强水土保持宣传教育,建立对施工单位的约束条件;三是督促变更备案工作,促进有关各方的信息沟通和职责发挥;四是制定监理操作性强的"三控制"措施,做好与主体工程监理的沟通协调;五是建立档案管理制度,规范档案管理行为。 相似文献
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采集草海流域周边成熟期整株农作物及土壤样品,分析测试其中DDTs和HCHs的含量,对比研究了土壤和作物中DDTs和HCHs污染水平及其在作物中富集能力。结果表明：研究区域土壤中HCHs和DDTs残留检出率均为100％,残留范围分别为0．06～16．66μg·kg^-1和0．08-39．77μg·kg^-1,土壤中HCHs和DDTs的残留量均小于国家土壤环境质量一级标准;三种农作物中DDTs、HCHs及∑（DDTs,HCHs）残留量差异显著,HCHs含量最高的是玉米,DDTs和（DDTs,HCHs）最高的是马铃薯;三种农作物中HCHs和DDTs残留的风险系数均为1．1,属于低度风险,农作物中DDTs、HCHs及∑（DDTs,HCHs）的安全指数IFSc均小于1,DDTs和HCHs残留量对三种农作物安全影响的风险是可以接受的。 相似文献
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我国亚热带山地丘陵区特征及开发中的有关问题 总被引：1，自引：0，他引：1
我国亚热带山地丘陵区，山多地少、人口众多、经济基础薄弱，生态环境严重恶化，障碍着区内经济的发展，区内开发应按照以下几个方面搞好：１、协调山－林－地－人的关系；２．调整粮食－林牧－融渔关系；３．改善生产－生活－生态环境。４．提高生态－经济－社会效益。 相似文献
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为了解土壤在Pb、Cd单一以及复合污染条件下红薯对Pb、Cd的吸收和积累规律,通过盆栽试验对红薯地上部和地下部的生物量和重金属含量进行测定,分析了单一及复合污染土壤中重金属Pb、Cd形态分布特点。结果表明,相对于对照,较低浓度的Pb、Cd能显著促进红薯的生长（P〈0.05）,Pb超过50mg.kg-1、Cd超过3mg.kg-1时,红薯生长受到显著抑制（P〈0.05）,Cd是影响红薯生长的主要因素;随着试验处理浓度的升高,红薯体内重金属含量也随之升高,二者之间存在极显著的相关性（P〈0.01）,Pb、Cd共存对红薯吸收累积Pb、Cd具有明显的交互作用,Pb促进Cd向地上部转移,Cd促进Pb在地下部积累。根际土壤中Pb、Cd以可交换态与碳酸盐结合态为主,二者均占总量的55以上,在复合污染条件下,Pb浓度为50mg.kg-1时其活性系数显著高于其他Pb处理（P〈0.05）,并在很大程度上促进有效态Cd含量的增加。 相似文献
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There is a declining gradient of wet SO4 deposition from south to north in Nova Scotia with the highest values being in the south, along with a localized increase around the Halifax metropolitan area, due to local SO4 emission. Edaphic conditions such as drainage from soils containing gypsum or drainage on disturbed rocks containing pyrite, provide additional SO4 to surface waters.Acidity is usually absent in the former (pH > 7.0) and very high in the latter (as low as pH 3.6). By contrast peaty, organic drainages release water low in SO4 during the growing season but they release high amounts of organic anions (A?), consequently, these waters maintain decreased pH values, usually < 4.5. A study of over 80 wetlands and lakes during the ice free period in Nova Scotia showed that sea salt corrected SO4 concentrations range from 45 ueq L?1 in the south end of the province, ～30 ueq L?1 in the Kejimkujik area and < 17 ueq L?1 in the northern areas with values > 85 ueq L?1 in the Halifax area, reflecting the atmospheric deposition pattern of SO4 The SO4 concentrations may be > 2000 ueq L?1 in drainages containing gypsum, > 700 ueq L?1 in drainages over pyrite bearing socks but < 20 ueq/L?1 in streams draining bogs. The SO4 concentrations change considerably during the non-growing season when the ground is saturated with water or frozen, and the runoff is high (snow and rain often alternate in winter). Under such conditions SO4 concentration drops in the two former cases and increases in bog drainages, accompanied with a considerable drop in (A?) concentrations. Care should be taken when interpreting SO4 concentrations in surface waters in Nova Scotia with respect to atmospheric SO4 deposition. 相似文献
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In this study, we investigated the extent of peatland degradation and development in Peninsular Malaysia and in the islands of Sumatra and Borneo, in the western part of insular Southeast Asia, since 1990. Furthermore, carbon emissions caused by these land cover changes were estimated in order to evaluate their contribution to global climate change. High resolution Landsat (30 m spatial resolution) and Satellite Pour l'Observation de la Terre (SPOT; 10–20 m) satellite images were used to derive information on land cover in 1990 and 2008. Analysis of land cover changes since 1990 revealed remarkable reduction and degradation of peatswamp forest ecosystems. In less than 20 years, 5·1 Mha of the total 15·5 Mha of peatland had been deforested (11·6 Mha → 6·5 Mha; 75 per cent → 42 per cent) and the great majority of the remaining forests had been selectively logged. Simultaneously, area covered by unmanaged secondary growth ecosystems had doubled to nearly a quarter of all peatlands and industrial plantations had expanded dramatically (0·3 Mha → 2·3 Mha; 2 per cent → 15 per cent). It was conservatively estimated that these changes have caused minimum of 1·5 Gt carbon emissions into the atmosphere since 1990. Currently, peatlands of the study area emit at least 81 Mt of carbon (equivalent to 300 Mt of carbon dioxide) on annual basis due to mere peat decomposition. Thereby, it was concluded that peatland degradation and development in insular Southeast Asia during the past two decades have not only put the existence of Southeast Asian peatswamp forest ecosystems in danger but it has also caused globally significant carbon emissions and created a constant source of carbon dioxide. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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大棚和露地环境下,分别对番茄植株一次性喷洒推荐剂量的百菌清（CHT）和毒死蜱（CHP）,研究喷药后两周内农药在番茄根、茎、叶和果实中分布的持久性及其动态降解规律。实验结果表明,百菌清在大棚番茄中的残留浓度分布呈现为叶片垌果实〉茎〉根;毒死蜱呈现为叶片〉果实垌茎〉根。大棚番茄各部位的最高残留浓度出现时间滞后于喷药时间8~60h;空间浓度分布上表现为大棚中间区域浓度高于两侧,这与棚内的空气对流有关。大棚番茄果实中百菌清和毒死蜱的残留半衰期分别为5.8d和7.2d,明显高于文献报道。 相似文献
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Distribution and fractionation of heavy metals in pairs of arable and afforested soils in Denmark 总被引：1，自引：0，他引：1
M. K. Andersen K. Raulund -Rasmussen H. C.B. Hansen & B. W. Strobel 《European Journal of Soil Science》2002,53(3):491-502
Afforestation of sandy arable soils in northern Europe is likely to lead to an increase in the soil's acidity and changes in the behaviour of the organic matter, and this might affect the ability of the soil to retain heavy metals. It is important to assess the impact of such a change in the land use on the solubility of the heavy metals and to assess the risk of leaching to surface‐ and groundwater and the possible entrapment of heavy metals in the tree canopy. The impact of afforestation was assessed by excavating soil profiles in adjacent 34‐year‐old Norway spruce stands and arable plots at four different sites. We found that after 34 years the pH had decreased and cations were depleted in the topsoil under forest. The aqua regia‐extractable heavy metals were determined, and the heavy metal binding within the soil was assessed using a modified version of the BCR (Community Bureau of Reference) sequential extraction procedure. Higher contents of heavy metal were found in the arable plots in the loamy sand soils. Cadmium was found only in the most mobile fractions. The content of Pb in the subsoil was strongly correlated with the clay content, but not in the topsoil, which suggested that Pb had been added to the topsoil. We found strong correlations between the clay content and the Cu, Ni and Zn in the residual fraction, leading us to conclude that much of the Cu, Ni and Zn is of geological origin. No significant differences in the heavy metal fractionation between forest and arable soil were found, presumably because 34 years of different land use is not long enough to produce such differences. 相似文献
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Abstract The effect of bacterial inoculation of Rhizobium fredii HN01 on the immobilization and speciation of Cu, Zn, and Cd was studied in Red and Cinnamon soil which are typical Chinese soils. The soil was mixed with bacterial suspension for one week followed by an immobilization of each heavy metal for another week. The total binding and fractionation of heavy metals in soils were analyzed. As compared with the control, the retention of total Cu, Zn, and Cd in Red soil increased by 28, 16, and 28%, respectively, in the presence of rhizobia. The amount of exchangeable, NH4OAc-extractable, Mn oxides-bound and organic matter-bound Cu increased by 23–123%. There were significant decrease of exchangeable Cu and marked increases of NH4OAc-extractable and Mn oxide-bound Cu in Cinnamon soil with the presence of rhizobial cells, although no changes for the total retention of Cu were observed. The amount of exchangeable Zn in Red soil-rhizobia composite was 20% greater than that of the no-rhizobia soil. Addition of rhizobia also increased exchangeable Cd and specifically-adsorbed Cd by 25 and 93%, respectively, in Red soil. No considerable differences were found for the total immobilization of Zn and Cd as well as their distribution in various solid fractions of Cinnamon soil in the absence and presence of rhizobial cells. In terms of soil components, it is assumed that bacterial biomass had a relatively less impact on the species of heavy metals bound with Fe oxides. Results suggested that the retention and speciation of heavy metals in soil are governed largely by the interactions of bacteria with various inorganic and organic soil constituents. The data are useful in understanding the impact of microorganisms on the behavior, mobility and transformation of heavy metals in soil environments. 相似文献
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Three months after neutralization concentrations of methylmercury (MeHg) were higher in the water of the limed than in the control basin of a small lake. After two years, the concentrations in the limed basin were somewhat lower than in the control (0.056–2.19 ng L?1 and 0.129–2.65 ng L?1, respectively). The highest concentrations were found in the anoxic hypolimnia. The total amount of MeHg in the water mass of the lake varied from 19 to 68 mg, showing a drop after spring and autumn overturns and a maximum during stratification periods. The total Hg concentrations of fish in L. Iso Valkjärvi varied from 0.06 to 0.14 μg g?1 (ww) in whitefish to 0.1 to 0.7 μg g?1 in perch and to 0.2 to 1.4 μg g?1 in pike. The total amount of MeHg bound in the fish of the lake was quite similar to that in the water column, 43 to 59 mg in 1990–1993, 33 to 47 mg of which was in the perch population. 相似文献