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1.
对镜湖水质富营养化的研究结果表明,镜湖水体溶氧丰富,五日生化需氧量(BOD5) 、化学需氧量(COD)、总磷(TP)、总氮(TN)、叶绿素a(Chla)严重超标.对单项污染指数(Ii)、卡尔森富营养化指标(TSI)的测算和评价也表明镜湖水体处于富营养化状态 .本文并提出了治理的初步措施.  相似文献   

2.
对镜湖水质富营养化的研究结果表明,镜湖水体溶氧丰富,五日生化需氧量(BOD5)、化学需氧量(COD)、总磷(TP)、总氮(TN)、叶绿素a(Chla)严重超标。对单项污染指数(Ii)、卡尔森富营养化指标(TSI)的测算和评价也表明镜湖水体处于富营养化状态。本文并提出了治理的初步措施。  相似文献   

3.
通过对镜湖水质富营养化的初步研究,表明镜湖水体处于富营养化状态,并提出了治理的初步措施  相似文献   

4.
选取丹江口水库丹库和汉库的15个监测断面,采用相关加权综合营养状态指数评价法,对2018年丹江口水库水体营养状态进行了逐月评价,同时对相关水质参数包括高锰酸盐指数、总磷、总氮、透明度和叶绿素a等营养状态参数的权重结果进行了分析. 结果表明:2018年丹江口水库总体呈中营养状态,综合营养状态指数范围为31.9~37.9,汉库高于丹库. 其中汉库中心、柳陂镇山跟前2个监测断面在7—8月份接近轻度富营养化;总氮和叶绿素a是影响丹江口水库水体营养程度最重要的2个参数,其次是总磷和透明度,高锰酸盐指数对水库水体营养程度影响较小. 在营养状态分析和评价的基础上,提出了丹江口水库富营养化防治的对策建议,包括加强水库管理、构建生态过滤净化技术措施、开展水库总氮控制和藻类防治科学研究.   相似文献   

5.
采用综合营养状态指数法对仙溪湖水体富营养化状况进行评价,结果表明:仙溪湖目前已经处于轻度富营养-重度富营养状态,枯水期水体富营养化严重,水质最差,平水期次之,丰水期水质最好。从仙溪湖上游至下游水质有逐渐好转的趋势,氮、磷是仙溪湖水体富营养化的主要限制因子。最后,分析了仙溪湖水体富营养化成因,并提出一些防治对策和建议。  相似文献   

6.
为了解矿区塌陷水体的水质污染特征及规律,结合物理、化学和生物指标,运用营养状态综合指数法及基于ARCGIS的空间差值分析法对淮南矿业集团谢桥矿塌陷塘水质进行了分析与评价。矿区塌陷塘水质pH值呈弱碱性,透明度较低,BOD5、CODMn指标含量较高;用营养状态综合指数法对塌陷塘水质富营养化进行了评价,其污染级别为轻度富营养;运用ARCGIS的空间分析模块,利用总磷、总氮、BOD5、CODMn4个因子的空间插值栅格图建立多因子综合污染模型进行综合评价,得出水体综合水质标准处于地表水Ⅲ类到Ⅳ类之间,水质有待改善。本研究结果为塌陷塘水体水质监管及管理提供科学依据。  相似文献   

7.
玄武湖水体富营养化水质预测模型预测了湖泊的水位、水温、悬浮物、颗粒磷、可溶解磷、总磷、浮游植物和透明度等参数的月平均值,并对玄武湖的富营养程度进行了判别.  相似文献   

8.
2014年5—11月对涝河水库水质进行了监测和评价。结果表明:水库一年中水位变化较大,导致水体透明度和总磷变化也较大;其余因子中,总氮超标较为严重,高锰酸盐指数含量较低,溶解氧充足。根据综合营养状态指数法,水库春、夏季呈现富营养化状态,秋季水质为中营养状态。  相似文献   

9.
太湖富营养化的驱动因子分析   总被引:15,自引:2,他引:13  
将太湖2001~2002年的水质监测数据与空间数据结合,采用基于因子分析的主成分方法将太湖的水质参数概括为5个主成分,提取并反证了湖泊水质各个主成分的科学内涵,即水体营养指数、富营养化指数、植物生长环境指数、水体色度指数和水体酸碱指数;研究了各主成分的空间分布特征、意义以及月均值随时间的变化规律.指出水体营养指数和植物生长环境指数是太湖富营养化的主要驱动因子,水体色度指数和水体酸碱指数是太湖富营养化的次要驱动因子并可作为富营养化的指示因子。  相似文献   

10.
本文对芜湖市镜湖、九莲塘、汀塘等主要地表水体营养状态进行了综合评价,分析了水体富营养化污染的特点及其成因,并提出了防治水体污染的对策措施。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

15.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

20.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

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