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1.
采用生态因子质量等级评分加权综合质量指数法对贵州86个县级行政区划单位的生态环境质量进行评价,并按综合质量指数的高低将生态环境质量划分为优、良、中、差4个等级,得到各个县域生态环境质量评价结果.根据该结果,按照地理区划的基本原则和方法,对贵州生态环境质量进行分区,将全省划分为3个生态环境质量区,并就各区的生态环境质量现状和建设保护的对策措施作了简要说明.  相似文献   

2.
贵州省生态环境质量评价及生态环境质量区划   总被引:3,自引:0,他引:3  
采用生态因子质量等级评分加权综合质量指数法对贵州86个县级行政区划单位的生态环境质量进行评价,并按综合质量指数的高低将生态环境质量划分为优、良、中、差4个等级,得到各个县域生态环境质量评价结果。根据该结果,按照地理区划的基本原则和方法,对贵州生态环境质量进行分区,将全省划分为3个生态环境质量区,并就各区的生态环境质量现状和建设保护的对策措施作了简要说明。  相似文献   

3.
甘南州生态质量状况及评价体系的构建   总被引:1,自引:0,他引:1  
为客观地反映甘南州近几年生态环境的质量,认识和定量描述生态环境恶化的现状,进一步保护与改善当地生态环境质量,文章就生物丰度指数、植被覆盖指数、水网密度指数、土地退化指数、污染负荷指数五个评价指标作为生态环境质量的分指数,采用综合权重评价法对该区域内各县区近年来的生态环境质量进行综合评价,确定出评价等级,结果令人满意.  相似文献   

4.
济南市生态环境质量现状评价   总被引:8,自引:0,他引:8  
在建立评价指标体系的基础上 ,运用层次分析法与综合指数法对济南市生态环境质量现状进行了考核和评估 ,将全市生态环境质量划分为不同生态水平的 5个等级 ,为各不同区域不同生态问题的识别、生态保护目标及对策的制定提供科学的依据 .  相似文献   

5.
以鄂尔多斯市生态环境质量为研究对象,运用加权合成法得出生态环境质量综合指数并进行评价分析,在此基础上运用灰色方法建立预测模型,得出预测值.研究表明:从1990-2010年,生态环境质量总的趋势是不断变好,但在不同的阶段生态环境质量所处的等级不同,从1990-2000年生态环境质量处于一般等级;从2001-2010年生态环境质量处于良好等级.通过预测得出环境质量综合指数不断上升,环境质量不断改善,到2016年环境质量开始进入优等级.  相似文献   

6.
生态环境是以人类为中心的各种自然要素和社会要素的综合体,本文利用生物丰富度指数、植被覆盖度指数、水网密度指数、土地退化指数和污染负荷指数建立了生态环境质量评价指标体系,运用综合评价法对绥化市的生态环境质量进行评价。结果表明:绥化市生态环境质量EQI的范围在42.21~61.35,其中,绥棱和庆安两个地区的生态环境质量最好,北林区、肇东和海伦三个县市的生态环境质量为良,安达、兰西望奎等五地区的生态环境质量为一般。  相似文献   

7.
流域生态环境质量对于流域可持续发展具有重要影响.借助RS和GIS技术获取土地利用数据,并以此为评价主要基础数据,通过生物丰度指数、植被覆盖指数、水网密度指数、水土保持指数和污染负荷潜力指数五个评价因子建立综合指数评价模型,对小清河流域1984-2010年生态环境质量进行分析评价.结果表明流域生态环境质量属于“一般”级别,生态环境总体有所改善,但仍需要继续加强流域生态环境保护力度,以促进流域可持续发展.  相似文献   

8.
生态环境是人类生存发展的物质基础,生态环境质量深刻影响着全球变化及区域可持续发展。为了分析玛纳斯河流域的生态环境质量现状及变化特征,本文以1993、2006和2016年的Landset TM/ETM影像为数据源,借助RSEI指数,对玛纳斯河流域的生态环境质量进行监测和动态评价。结果表明:(1)绿度、湿度、热度和干度是生态系统的重要组成部分,在此基础上建立的RSEI指数可较好的反映玛纳斯河流域生态环境质量状况及其时空分异;(2)1993、2006和2016年RSEI指数均值分别为0.31、0.38和0.45,对RSEI指数进行分级处理后,发现流域生态环境质量"差"等级居于主导地位,"优"等级等级急剧增加,流域内生态环境质量向好的方向发展;(3)流域山地-绿洲-荒漠生态系统(MODS)内部生态环境较为稳定,流域内生态环境质量变好的区域远大于变差的区域,生态质量变差的区域主要集中于南部山区林地、水域、城市周边和部分耕地,生态质量变好的区域主要分布在绿洲内部及边缘。  相似文献   

9.
基于因子分析和聚类分析的生态环境质量评价   总被引:5,自引:0,他引:5  
从当前生态环境研究现状出发,采用因子分析法对影响生态环境质量的所有因素进行主成分分析及贡献大小评价、合成综合得分评估,同时利用聚类分析方法,对综合得分进行分类比较研究,确定生态环境质量的评价等级,为区域生态环境保护和规划治理提供依据.  相似文献   

10.
随着城市化的推进和发展,生态环境所面临的压力也逐渐加大,客观、准确、快速地评价区域生态环境质量显得极其重要.利用Google Earth Engine平台对2000、2010、2020年间岳阳市MODIS影像进行优化重构,明晰反映岳阳市生态环境质量的遥感生态指数(RSEI),从长时间序列中探明岳阳市生态环境质量的变化情况.综合遥感图像衍生出的绿度、湿度、热度、干度4个指标,对岳阳市2000—2020年生态环境质量进行监测和评价.研究表明,随着城市土地利用开发程度的不断增强,岳阳市的整体生态质量发生了阶段性变化,RSEI均值先从2000年的0.588上升到2010年的0.650,再下降至2020年的0.637,生态指数为良等级的区域面积所占比例从2000年的42.3%上升到2010年的68.3%,再下降到2020年的55.8%.  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 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   

13.
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   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

15.
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   

16.
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   

17.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

18.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

19.
20.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

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