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1.
新立城水库藻类污染成因分析及治理对策措施   总被引:1,自引:0,他引:1  
本文对新立城水库发生蓝藻水华事件进行了水质应急监测和污染成因分析.从新立城水库气象条件分析,发现水库水温是历史同期最高值,为藻类在库区内大量迅速繁殖提供了温度条件;从新立城水库坝前、库中和库末氮磷浓度分析,发现水库氮磷浓度均超过富营养化临界值,为藻类在库区内大量迅速繁殖提供了营养条件.本文在分析水库藻类污染成因基础上,提出了从水库管理和现有水处理系统的改进入手,加强新立城水库外源污染控制对策措施和内源污染治理措施.  相似文献   

2.
以淀山湖为研究区域,利用Landsat系列遥感影像,提出了归化蓝藻指数的构建方法,结合波段组合和Gabor滤波器构建多特征空间,并基于变精度粗糙集和灰色关联决策相结合的方法进行特征空间的优化。在此基础上,采用小波核双重加权SVM分类模型,得到研究区蓝藻水华空间分布格局的识别与检测结果。以误差矩阵证明此分类模型能够较准确地识别出蓝藻水华覆盖区,满足环境调查的要求。研究成果为淀山湖蓝藻水华的防治和水生生态系统的保护提供了科学依据。  相似文献   

3.
在全球气候变化的影响下,湖泊蓝藻水华面临着规模扩张、频率增加和持续时间延长的发展趋势,严重威胁着湖泊生态系统服务功能和人体健康。系统阐述了外部环境因子和内部生理生态特征对湖泊蓝藻水华发生的作用机制,探讨了气温升高、CO2浓度增加、极端气候事件频发对湖泊蓝藻水华发生机制的影响途径和过程,初步搭建了以“机理解析—模型构建—模拟预测—风险评估”为主线的气候变化对湖泊蓝藻水华的影响研究框架,并提出了应对气候变化的湖泊蓝藻水华防控策略。针对目前研究存在的问题,从大数据监测平台搭建、机理模型构建及风险预测、营养盐控制标准制定、防控政策制定等方面提出了未来研究的重点方向,以期为湖泊蓝藻水华的综合防治提供科学支撑。  相似文献   

4.
湖泊蓝藻水华生态灾害形成机理及防治的基础研究   总被引:9,自引:0,他引:9  
湖泊具有供水、渔业、旅游、维持区域生态系统平衡等功能,是支撑我国经济和社会发展的重要资源之一。但是近30年来,湖泊富营养化所导致的蓝藻水华频繁暴发,生态灾害事件频发,严重影响湖泊功能的发挥, 制约区域经济可持续发展。针对国家在保障区域水安全和生态安全、保护人民健康及建设和谐社会等方面的重大需求,国家重点基础研究发展计划项目“湖泊蓝藻水华生态灾害形成机理及防治的基础研究”于2008年7月正式立项。项目拟解决的关键科学问题包括:①湖泊蓝藻水华主要衍生污染物的形成机理、迁移转化规律和毒理效应;②蓝藻水华导致湖泊生态系统结构变化和功能退化的机理;③蓝藻水华生态灾害评估及调控机理。针对上述科学问题,项目以蓝藻水华污染物的产生、湖泊生态系统结构与功能的响应以及生态灾害的评估与调控为研究主线,重点开展以下几个方面的研究:①蓝藻水华衍生污染物的产生及其环境过程;②蓝藻水华衍生污染物的毒理效应与生态和健康风险;③蓝藻水华导致湖泊生态系统结构变化与功能退化的关键过程和机制;④蓝藻水华灾害治理和调控的的技术原理和途径。项目的实施和完成将为我国湖泊蓝藻水华生态灾害的预防与控制提供理论和技术原理支撑。  相似文献   

5.
污染土的研究是岩土工程研究领域中的一个新课题, 在工程中污染土可以引起地基强度降低, 导致建筑物失稳或破坏, 因此研究污染土污染机理、性状、评价和处理方法变得尤为重要, 本文从污染土的研究现状出发, 介绍了污染土的特性、污染机理、监测、评价等, 并对污染土的处理方法进行了研究。   相似文献   

6.
水源水库水质污染与富营养化控制技术研究进展   总被引:12,自引:1,他引:11  
水库作为城市的主要供水水源意义重大,近年来不断出现的富营养化及水质恶化等问题,使水源水库水质污染控制技术研究成为城市供水领域研究的热点课题.回顾了水源水库的水质问题.介绍了内源污染及突发性或周期性高强度水质污染研究方法和结论,并分析了其合理性.将现有的混合充氧技术、扬水曝气技术、上覆水中N、P、有机物生物去除方法及污染沉积物修复方法进行了对比分析.指出了目前该研究领域存在的问题,并对未来研究重点及发展趋势作了进一步展望.  相似文献   

7.
太湖富营养化与蓝藻水华引起的饮用水危机——原因与对策   总被引:58,自引:0,他引:58  
[ZW(*][HT6H]〓收稿日期:. 〓作者简介:[HT6SS](1963 ),男,江苏苏州人,研究员,主要从事水环境研究.[WT6HZ]E mail:[WT6BZ]qinbq@niglas.ac.cn[ZW)] [HT4F][HT5K]()[JZ)] [HT5H][GK2] 摘〓要:[HT5K]2007年5月份发生在无锡太湖蓝藻水华引起的自来水危机事件进一步凸现我国湖泊富营养化的严峻局面和蓝藻水华频发的现状。从分析太湖富营养化发生、发展,蓝藻水华爆发的原因和机制入手,提出湖泊富营养化治理和蓝藻水华控制的途径和措施。研究表明,太湖富营养化之所以如此严重而且治理起来异常艰难,主要是由于太湖发育于长江中下游洪泛平原,营养本底高;由于水浅和沉水植被的退化使得频繁的风浪扰动造成内源营养盐负荷维持在一个非常高的水平;而流域内社会经济的高速发展,进一步加剧了太湖富营养化进程。蓝藻水华爆发一方面与蓝藻本身的生理特征有关,如固碳、伪空泡、光吸收及营养盐利用的能力;另一方面则与系统内物理、化学、生物环境有关,如独特的浅水湖泊水下光场结构和低的捕食压力。太湖的富营养化治理需遵循控源截污、湖泊生态修复和流域管理的原则,具体措施包括前置库和人工湿地的面源污染物控制技术;物理机械和生物去除内源营养盐削减技术;沉水植被恢复的湖泊生态修复技术。而蓝藻水华的控制技术则包括围隔拦截和导流的物理工程方法、絮凝沉降和抑藻物添加的化学工程方法以及生态浮床和生物操纵的生态工程方法。具体使用时,需要先诊断、后治理。    相似文献   

8.
环境矿物材料在土壤,水体,大气污染治理中的应用   总被引:39,自引:11,他引:28  
本语文在简要阐明了环境矿物材料对污染和净化机理与净化功能的基础上,明确了环境矿物材料的领域,重点展望了在土壤重金属污染防治、地表水和地下水水质改善及燃煤固硫除尘等三类状态污染控制与环境保护领域中应用的前景。认为经济、简便、有效地用于污染治理与环境修复的无机界矿物学方法类似于有机界这方法,均是自然界地球系统中天然自净化作用的反映。  相似文献   

9.
湖相沉积物中重金属环境污染研究进展   总被引:6,自引:1,他引:6  
综述了湖相沉积物重金属环境污染研究进展。介绍了该领域研究的主要研究内容、主要研究方法和湖相沉积物重金属污染的评价方法。并指出了该领域研究中比较薄弱的环节以及将来的发展方向,以期推动该领域的进一步研究。  相似文献   

10.
综述了湖相沉积物重金属环境污染研究进展。介绍了该领域研究的主要研究内容、主要研究方法和湖相沉积物重金属污染的评价方法。并指出了该领域研究中比较薄弱的环节以及将来的发展方向,以期推动该领域的进一步研究。  相似文献   

11.
干旱区山地典型流域不同景观结构的水文调节能力分析   总被引:1,自引:0,他引:1  
在GIS支持下,对祁连山中段典型流域不同景观结构的水文效应进行比较分析.结果表明:以低海拔乔木林占优势的大野口河流域可对其年降水量的36.45%进行调节,雨季径流深是旱季径流深的8.43倍;以较高海拔灌丛占优势的海潮坝河流域可对其年降水量的24.96%进行调节,雨季径流深是旱季径流深的11.8倍.大野口河流域对降水的调控能力强于海潮坝河流域.在降水量不变的情况下,流域森林面积每增加1 km2,流域对降水的综合调节能力将提高0.35 t.100 m-2(即3.5mm).  相似文献   

12.
The contamination of organochlorine pesticides (OCPs) from the selected rivers in Okinawa Island was investigated to estimate the current status of pollution in water, plants and surface sediments in these rivers. The Aja River, Asato River, Houtoku River, Kokuba River and Okukubi River were selected for this study. The concentration of the total pesticides were in the range of 0.94-231.8 ng/L in river water, 0.006–191.6 ng/L dry weight in river sediments and 0.001–55.8 ng/L dry weight in plants. Among the OCPs, ΣHCB of α-BHC,β-BHC and Aldrin were the common detected compounds in river water. The α-BHC, Aldrin and Dieldrin were the most frequent detected compounds in river sediments and α-BHC and Dieldrin were the common OCPs detected in plants. Aldrin, Dieldrin and ΣHCB were in abundance. Various contamination patterns between the selected river water, sediments and plants were observed. Aja River, Asato River and Houtoku River were contaminated with α,β,δ,γ- BHC, Aldrin and Dieldrin (water and sediments) whereas the main OCPs in Kokuba River and Okukubi River were Dieldrin (plants) The OCPs levels in all rivers were generally below guideline values in Japan, but some sites displayed levels which exceeded the EC and WHO Standards for Aldrin, Dieldrin and α,β-BHC.  相似文献   

13.
祁连山区森林景观格局对水文生态效应的影响   总被引:14,自引:0,他引:14       下载免费PDF全文
在地理信息系统ArcGIS环境下,结合1987-2001年的水文资料,用Spatial Analyst、Hydrologic Modeling等扩展模块,对祁连山中段北坡大野口河流域和海潮坝河流域的景观格局与水文特征进行比较分析,结果表明:大野口河流域的景观组分以低海拔的草地和乔木林占优势,草地所占面积最大,整个景观较为破碎;海潮坝河流域的景观组分以高海拔的裸地和灌丛占优势,裸地所占面积最大,景观破碎化程度相对较低。大野口河流域的蒸散发占降水量的61%,流域径流系数为0.39;而海潮坝河流域的蒸散发占降水量的41%,流域径流系数为0.59。研究表明,导致两流域生态水文效应相差较大的主要原因是两流域不同的景观格局。  相似文献   

14.
以层序地层学和沉积学理论为指导,依托大陆架科学钻探CSDP-2井并结合WX5-ST1井、N5井及南京江宁地区典型剖面,利用岩性、测井、古生物等资料,在识别苏北-南黄海盆地各级层序界面的基础上,将研究区上二叠统-下三叠统划分为2个长期基准面旋回(LC1、LC2)和3个中期基准面旋回(MC1-MC3)。研究表明,南黄海盆地与苏北盆地实为被海岸线分割的同一沉积盆地,其上二叠统-下三叠统具有良好的可对比性,其中:LC1长期基准面旋回(上二叠统)不对称性明显,最大海泛面MFS1对应于龙潭组中下部浅海陆棚相的泥岩,LC2长期基准面旋回(下三叠统)因后期印支运动抬升剥蚀,仅存基准面上升半旋回;研究区MC1旋回期(龙潭组)主要发育潮坪、泻湖、三角洲等海陆过渡相,各地水深相差不大;MC2、MC3时期(大隆组、青龙组)发育浅海陆棚、潮坪、泻湖及碳酸盐岩台地等沉积相,水体演变为南西深而北东浅,分析认为是东吴运动时期盆地差异抬升的结果。  相似文献   

15.
通过分析测试吉林省中部农业土壤中α-HCH、β-HCH、γ-HCH、δ-HCH 4种异构体和HCB的含量,对该地区HCH和HCB的残留情况进行了讨论。结果表明,在吉林省中部农业土壤中HCH4种异构体均有不同程度的检出,其中β-HCH和γ-HCH为主要的残留物。ΣHCH残留量介于0.42~44.96 ng/g之间,平均值为5.09 ng/g;ΣHCH残留量在不同类型土壤和不同利用方式下土壤中差异不明显。农业土壤中α-HCH/γ-HCH比值均接近于1,指示该地区土壤环境已经发生变化,也可能有新的污染源存在。土壤中HCB平均值为5.51 ng/g,总体残留水平比较低,且在水田中的残留量高于在旱田中的残留量。  相似文献   

16.
Detrital zircons in five sedimentary samples, MC1 to MC5, from the bottom of the Chuanlinggou Formation in the Ming Tombs District, Beijing, were dated with the LA-ICP-MS and SHRIMP U–Pb methods. Age spectra of the five samples show a major peak at 2500 Ma and a secondary peak at 2000 Ma, suggesting their provenances were mainly from the crystalline basement of the North China Craton and the Trans-North China Orogen. The youngest zircon has an age of 1673 ± 44 Ma, indicating that the Chuanlinggou Formation was deposited after this age. From sample MC4 to MC5, lithology changed from a clastic rock (fine-grained sandstone) to a carbonate rock (fine-grained dolomite), suggesting that the depositional basin became progressively deeper. The age spectrum of sample MC5 shows a major peak at 2500 Ma and a secondary peak at 2000 Ma. Sample MC4, which is stratigraphically lower than sample MC5, only had one peak at 2500 Ma. We conclude that there was a transgressive event when sediments represented by MC5 was deposited, and seawater carried ca. 2000 Ma clastic materials to the basin where the Chuanlinggou Formation was deposited, leading to the addition of ca. 2000 Ma detritus. Our research indicates that the source area for the sediments became more extensive with time. We conclude that the Chuanlinggou Formation in the Ming Tombs District was deposited in a low-energy mud flat sedimentary environment in the inter-supra tidal zone because it is mainly composed of silty mudstone and fine-grained sandstone with relatively simple sedimentary structures.  相似文献   

17.
The eastern Hexi Corridor Belt (HCB) is located in the transitional belt among the Alxa Block, the Qilian Orogenic Belt and the North China Block. Because of its unique tectonic location, the tectonic setting, provenance, and even the age of the sedimentary strata in the eastern HCB during the Early Paleozoic remain controversial. This study analyzes the provenance of the poorly studied Xiangshan Group, discusses its age of development and tectonic setting in the eastern HCB using a combination of petrological, geochemical and LA-ICP-MS U-Pb zircon dating methods. Based on the youngest age peaks and the fossil evidence, we suggest that the Xiangshan Group is Middle Cambrian to Late Ordovician in age. The complexity of the geochemical characteristics and associated diagrams suggests that the early stage of the Xiangshan Group developed in a passive continental margin environment, late in the back-arc basin of the eastern HCB. Based on the sandstone detrital composition, whole-rock geochemistry and detrital zircon ages, we conclude that the Xiangshan Group had an early provenance that was mainly from the Qilian Block and a late provenance from the Qilian Block and the western Alxa Block. The eastern HCB and its northern and southern blocks have similar palaeontology, lithology and basement age characteristics to the South China Block. This indicates that the eastern HCB might not have formed in the intra-continental aulacogen of the North China Block during the Early Paleozoic but has a close affinity to eastern Gondwana.  相似文献   

18.
The phosphorus (P) resources worldwide are limited, and the prices of commercial P fertilizer continue to increase. Therefore, the use of P containing wastes is important for P recycling in agriculture. The P fractionation methods have been widely applied to characterize the effect of land use practice on soil P dynamics. Information about effect of organic manures on available P and inorganic P (Pi) fractions in calcareous soils of Chaharmahal va Bakhtiari province is limited. The objectives of this research were to study the effect of municipal compost (MC) on available P and Pi forms in five calcareous soils. Municipal compost was applied at the rates of 0, 0.5, 1.0, 1.5 and 2.0% (w/w). Samples were incubated at 25?±?1°C and 20% moisture content for 150?days. At the end of incubation, available P in MC-treated soils was extracted by Olsen, AB-DTPA and 0.01?M CaCl2 methods. Also, phosphorus was fractionated chemically into labile P (LP), non-occluded P(NP), re-adsorbed P (RP), occluded P (OP), calcium phosphates (CaP) and residual P. The results showed that there was a linear increase in soil available P with MC application. There was a significant positive relationship between Olsen-P, AB-DTPA-P and 0.01?M CaCl2-P, and MC additions with slopes ranged from 0.471 to 0.583, 0.032 to 0.106, and 0.033 to 0.081, respectively. The increase in soil test P (STP) from MC additions was not related to the initial STP of the soils. A sharp increase in LP, NP and CaP and decrease in residual P concentration occurred in all soils with MC application. It can be concluded that MC applied to calcareous soils may enhance P nutrition of plants. Furthermore, applied P partitioning into the relatively available forms means the potential erosion losses of P to streams and other bodies of water.  相似文献   

19.
超微粒子水泥加固软土试验研究   总被引:1,自引:0,他引:1  
应用和研发各种固化材料,对软土进行固化和改性,以改善其工程特性是当今国际上研究的热点课题。通过室内试验,研究了一种新型超微粒子水泥材料(ALOFIX-MC,简称MC)加固软土的效果,分析了其加固和改性机制。试验中,MC以0 %、1 %、2 %、3 %、4 %和5 %的掺量分别掺入到水泥掺量15 %和石膏掺量2 %的软土试样中,配制了6组试样。室内无侧限抗压强度试验结果表明,在15 %掺量的普通水泥土中掺入少量MC就可以显著提高软土的强度和稳定性。扫描电镜(SEM)分析表明,MC的胶结填充作用和MC对水泥水化的促进、孔隙的填充以及其本身的表面吸水作用对加固效果有重要影响。研究成果为进一步提高水泥土的工程性质和减少常规水泥土中水泥掺量提供了一条新的途径。  相似文献   

20.
地质调查样品中有机氯农药分析存在的困难和解决方法   总被引:2,自引:2,他引:0  
宋淑玲  饶竹  赵威  李松 《岩矿测试》2010,29(3):271-276
9种有机氯农药(六氯苯、α-HCH、β-HCH、γ-HCH、δ-HCH、p,p′-DDE、p,p′-DDD、o,p′-DDT和p,p′-DDT)是国土资源地质大调查项目中水和土壤样品必测的有机污染物。有机氯农药自身结构和性质的特殊性以及地质调查样品的差异性,在采用气相色谱电子捕获检测器(GC-ECD)分析有机氯农药过程中仍然存在许多困难。文章结合大量地质调查样品中有机氯农药分析的实践经验,从溶剂与待测物响应值的关系、基质效应的表现、样品前处理以及仪器日常维护四个方面,介绍了针对不同样品和分析要求正确选择进样溶剂、判断和解决基质效应,并通过良好的仪器日常维护习惯确保地质调查样品中有机氯农药检测灵敏度达到要求。  相似文献   

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