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1.
核技术是治理环境污染方兴未艾的高新技术之一,在环境保护领域具有广阔的应用前景。在简要概述了核技术在环境保护中应用、研究现状的基础上,对其存在的问题及今后的主要研究方向进行探讨与展望。  相似文献   

2.
乐知  王沁 《安全与环境工程》2011,18(2):81-84,92
本文选择两种洗发水为研究对象,以松滋青皮豆为研究材料,通过试验应用蚕豆根尖细胞微核技术并结合生物量分析检测洗发水的毒性,结果表明:两种洗发水均能使蚕豆根尖细胞的微核率显著上升,并且随着处理液的浓度上升,微核率也相应增大,表明其具有较强的诱变效应;通过污染指数的分析表明,洗发水属于污染物,在极高浓度下具有非常强的致突变能力;生物量分析显示,随着处理液浓度的升高,蚕豆种子的生物量变化总体上呈下降趋势,但低浓度处理液可能具有一定的促进细胞分裂生长的作用。综合分析得出,洗发水的安全性状况存在问题。  相似文献   

3.
植物化感作用及其在农业生态系统中的应用   总被引:3,自引:0,他引:3  
介绍植物化感作用的概念、化感物质的种类、化感物质的释放、迁移和转化以及作用机制,并着重从人工混林农业系统、多作农业生态系统、防治杂草和植物病害、作物化感品种4方面概述了植物化感作用在农业生态系统中的应用。  相似文献   

4.
用蚕豆微核技术对淮南大通和谢二煤矿塌陷塘的水体水质进行监测,同时测定了水体的氯化物、电导率、CODCr、BOD5、DO和总磷、总氮。结果表明:大通和谢二煤矿塌陷塘水质已经受到中度污染;蚕豆微核技术与氯化物、电导率、CODCr、BOD5、DO和总磷、总氮具有一定的相关性。  相似文献   

5.
随着钢铁工业的快速发展,钢铁冶金渣(简称钢渣)的排放量逐年增多,目前我国年排放钢渣量约为1000万吨,利用率仅10%左右。钢渣的处理和利用处于较落后的状态,大量的钢渣至今没有得到有效的处置和利用,有些钢厂已是渣满为患,影响生产,对环境造成污染。钢渣是一种很有利用价值的再生资源,开发利用钢渣,特别是大宗用途方面,对于消除渣害,合理利用资源,保护环境,促进国民经济的持续发展,具有十分重要的意义。钢渣富含钙、镁、磷、硅和少量锰、锌和铜等,具有多种农作物的营养元素,在钢渣的综合利用中,农业上的施用是有效…  相似文献   

6.
随着工业、农业迅速发展,环境污染问题已经越来越严重,人们已经逐渐认识到环境保护的重要性.生物传感器在环境监测中的应用也越来越广泛,其不但具有选择性好、稳定性高、响应时间短的优点,同时还不需要对样品实时预处理,携带方便,可进行连续、实时、原位监测.本文就对生物传感器技术在环境监测中的应用进行研究.  相似文献   

7.
介绍了近年来生物絮凝剂的研究和应用现状,详细总结了几种生物絮凝剂的絮凝机理,并对生物絮凝剂的分类进行了阐述,列举了生物絮凝剂的应用情况,文中还提到了近年来的研究新进展,特别是提到了复合型生物絮凝剂的研制情况,最后文章对未来生物絮凝剂的发展趋势进行了叙述.  相似文献   

8.
本文扼要介绍了水生生物监测技术的理论依据、主要的方法,结合各水生生物监测法的研究成果和应用实例进行了简要的综述,并对水生生物监测法进行展望.  相似文献   

9.
文章介绍了水污染的常规生物监测方法的应用,以及现代生物监测方法的研究进展情况,并指出了我国生物监测技术存在的问题和发展的方向。  相似文献   

10.
提出了采用加压、加酸处理和加适当的转化剂等方法,使生产硫酸铝废渣中的SiO2活化,并且配以不同比例的P、K元素研制成系列适用于不同作物的新型磷钾配方肥,能显著或极显著地提高作物的产量和品质。  相似文献   

11.
The economics of climate change in agriculture   总被引:1,自引:0,他引:1  
This paper presents a conceptual frameworkof the impact of climate change onagriculture. It assumes that climatechange will result in a fertilizationeffect and a shift of agro-ecologicalconditions away from the Equator towardsthe Poles. The agro-ecological shift islikely to reduce yield because of reducedacreage and the fertilization effect willincrease yield. The aggregate effectdepends on whichever of the two dominates. The overall effect of climate change may beless significant than its distributionaleffects and the results are consistentwith previous empirical studies. Theimpact of climate change depends on itspace. Faster changes in climate willresult in higher cost. The assessment ofthe cost has to consider that climatechange is a dynamic phenomenon that mayrequire continuous adjustment. Environmental regulation that emphasizesconservation may increase cost ofadjustment and environmental policiesshould emphasize adaptation andflexibility.  相似文献   

12.
Selenium occurs naturally in the soil environment in amounts which may cause nutritional toxicity or deficiency to livestock in areas throughout the world. Normal soils contain between 0.1 and 2.0 μg g?1 selenium compared with 30–324 μg g?1 (dry weight) or above from a seleniferous area. Plant selenium concentrations can generally be used as an indicator of the soil selenium status. Selenium accumulator plants may contain thousands of μg g?1 selenium and grow healthily on highly seleniferous soils. Most plants contain small amounts of selenium; less than 1 μg g?1 when growing on normal soils. A third group of plants, containing large amounts of sulphur, contain higher amounts of selenium when growing on normal soils.Animals consuming plants containing unusually small or large amounts of selenium over a prolonged period may develop nutritional selenium disorders. Development of sensitive analytical techniques has permitted detection of the very low amounts of selenium present in livestock suffering from selenium deficiency and associated problems. Required amounts of selenium necessary for animal nutrition range from 0.04 to 0.10 μg g?1 depending on the animal species and the level of vitamin E in the diet. Amounts of selenium causing nutritional toxicity are usually an order of magnitude higher than those producing deficiency.Factors affecting selenium absorption in animals include the form of selenium in the diet and the type of animal. Ruminants moderate their dietary intake by reducing selenium to insoluble forms, which they excrete. Monogastric animals, by contrast, may absorb up to 80% or more of their dietary selenium intake, depending on its biological availability.Although there are areas where livestock poisoning occurs, much evidence has been accumulated to indicate that agricultural livestock is deficient, or bordering on selenium deficiency, in many areas of the world. Overt selenium deficiency in man has been reported in China, indicating the possibility of widespread non-overt sub-clinical selenium deficiency in humans. No definite evidence for human selenium toxicity has been reported.Although anthropogenic selenium contributes to the total selenium in the soil environment, most of it is biologically unavailable. Organisms such as bacteria and fungi reduce biologically available selenium to elemental insoluble forms, whilst others produce volatile organic forms of selenium which are lost to the atmosphere. Some bacteria are able to oxidise colloidal selenium so that it becomes biologically available. Whether the overall amount of biologically available selenium is increasing or decreasing in the soil environment is of vital consequence to agricultural productivity. It is recommended that work should be carried out to quantify amounts of available selenium that are lost from soil systems, and to identify the forms and amounts of selenium that enter the soil environment from natural and anthropogenic sources. Tests to indicate the presence of non-overt selenium deficiency in animals, such as blood selenium measurements, are recommended for areas under suspicion from soil and crop analyses.  相似文献   

13.
Sewage sludge utilization in agriculture leads to several advantages through the recycling of nutrient and organic matter to the land.Inorganic nitrogen as NO3−1and NH4+ becomes immediately available; organic nitrogen becomes available after mineralization, which depends on soil type and tends largely to diminish with time.The soluble forms of phosphorus are H2P04 and HPO42− and the percentage P-utilization can easily be predicted from the amount extracted by ammonium chloride.Potassium concentration in sewage sludge is negligible, but crop requirements for it are high and often comparable to those for nitrogen.Organic matter mainly affects soil structure by increasing soil porosity, stability of aggregates and water retention; other properties affected by organic matter addition are pH and cation exchange capacity, which tend to increase.Negative effects due to heavy metals (toxic and phytotoxic) and pathogens can arise following sludge addition to soil. Epidemiological studies in the U.K. indicate that infections can arise, in particular from the presence of Taenia saginata and Salmonella.A recent survey in the European Economic Community (E.E.C.) revealed that nowadays 75% of sewage is treated and 40% of the residual sludges are used in agriculture (about 2 million t (2 M t) of dry solids year−1), affording a saving in mineral fertilizers of about 206 000 M L It. year−1 (£82AM; DM 295M; 100M FF). This economic advantage covers the cost of transport over a distance of 8 km and that of spreading the liquid sludge.This paper also compares the legislations of some countries concerning sewage sludge utilization in agriculture and shows that generally the countries with more experience in sludge utilization (France, Germany and the U.K.) permit disposal of higher concentrations of heavy metals.  相似文献   

14.
大香格里拉地区植被空间分布的环境特征   总被引:2,自引:0,他引:2  
以植被种类丰富的大香格里拉地区为研究区,利用气象站点数据、数字高程数据(DEM)以及该地区植被分布图,通过最大熵模型(Maxent)和ArcGIS软件的空间分析功能,研究该地区典型植被空间分布的环境特征,分析了大香格里拉地区植被分布的气候特征和地形特征,量化了植被空间分布的气候范围,并根据二者的关系特征,得到了植被与气候因子关系模型。同时,界定了不同植被分布的海拔、坡度、坡向范围。发现大香格里拉地区影响不同植被空间分布的气候因子不同,影响草甸分布的是多年平均最低气温和多年7月平均气温,影响针叶林分布的是多年平均最低气温和多年平均日照时数,影响灌丛分布的较分散。同时不同植被的海拔分布界限和坡度不同,坡向对植被分布的影响不明显。研究结果可为该地区植被保护和管理,以及植被的气候变化响应提供基础参考。  相似文献   

15.
通过对中运河宿迁段2001~2002年进行水质监测,结合历年监测资料,分析了中运河宿迁段氮污染特征。  相似文献   

16.
广东省农业氮足迹分析   总被引:7,自引:0,他引:7       下载免费PDF全文
为对农业生产氮素利用和排放情况简单直观而又全面地评估,基于修正的N-Calculator模型的基础上,结合农业生产系统中的氮素流动过程,计算了广东省农业氮足迹.研究发现,该省农业氮足迹的主要来源是化肥施用和养殖业饲料,2010年,两者合计占约81%以上.近20年来,农业氮足迹总量上升了45%,按用地平均更增长了88%,增速最快的是来自非农业部门的大气沉降氮,年增速8.5%,农业能源氮足迹是另一增长较快的项目,增幅为107%.污染氮足迹已占到总足迹的31%,主要是因为土壤的氮素流失.另外,2010年,与农业活动相关的其他部门的农业隐含氮足迹为207209.79t,约为农业氮足迹的17%.  相似文献   

17.
《汉语大词典》关于印香、至公、素华、鱼须、鱼鬚、鱼须笏六个词条的解释,或不准确,或有疏漏,或错误,有些书证也欠当。文章以文献为依据,一一予以辨析,并提出商补意见。  相似文献   

18.
Ecosystem services (ES), such as biological control, pollination, soil formation, nutrient cycling in agriculture are vital for the sustainable supply of food and fibre. The current trends of decline in the ability of agricultural ecosystems to provide ES pose great threat to food security worldwide. This paper discusses the concept of ES and identifies ES associated with agriculture. It discusses the economic and ecological benefits of these ES on farmland in general and its linkages with organic agriculture. The provision of ES on farmland may help to motivate the redesign of small-scale farms using new eco-technologies based on novel and sound ecological knowledge. This has potential to meet the food demand of growing population without damaging human health and the environment.  相似文献   

19.
大型盛事空气质量保障工作初探研究   总被引:2,自引:0,他引:2  
随着经济社会的迅速发展,中国举办的大型盛事越来越多,但同时由于近年来环境空气质量问题日渐突出,大型盛事的空气质量保障工作越来越重要。近些年来,全国各地在大型盛事空气质量保障工作上积累了许多宝贵经验,尤其是大连市在十二运期间环境空气质量保障工作上开创许多先进做法,为大型盛事空气质量保障工作做出了突出贡献。以大连市十二运空气质量保障工作为例,介绍了大连市的典型做法及空气质量保障工作成效,初步探索了中国大型盛事空气质量保障工作机制。  相似文献   

20.
Insecticides in health,agriculture and the environment   总被引:2,自引:0,他引:2  
  相似文献   

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