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1.
In August 1983, 18 samples were collected in Norwegian karst environments: seepage waters, surface flow upstream sinkholes or caves, allogenic and authigenie karst springs. Hydrochemical data (ion contents and computed variables for CO-CaCO system) are described by means of a factor analysis, the principal components analysis. Four factors, responsible for about 90 % of the total variance, are extracted and interpreted. Five clusters of samples are then identified:

– Authigenic karst waters (seepage and only carbonate aquifer);

– Waters of very short residence time (surface or karst flow);

– CO-rich waters (seepage and possibly organic-rich surface waters), CO2 part is discussed in more detail;

– CO-poor waters (surface waters above tree-line);

– a central group, combining 2 or more of these characters.  相似文献   

2.
北极海冰的大量融化,加速了北极航道开发和利用,对北极水域船舶事故风险管理提出了更高的要求。本文以2008—2017年的北极水域船舶事故数据为样本,运用数据挖掘技术和方法,对北极水域船舶事故进行了时空特征分析,并对船舶属性与事故属性之间的潜在映射关系进行了关联规则挖掘。结果表明:北极水域事故数逐年呈上升的趋势,事故主要发生在巴伦支海东部的俄罗斯摩尔曼斯克港口水域和挪威北部水域;北极水域严重事故受船舶总吨、船旗国、船舶类型、事故类型、事故水域等变量的影响,船舶尺度较大的船舶更容易造成严重事故;北极水域俄罗斯籍渔船的严重事故,很多是由机损事故引发的,但很少造成环境污染。研究结论可辅助海事管理部门和航运企业开展北极水域船舶事故预防和风险管理工作。  相似文献   

3.
In the Rocky Mountains, the association of increases in acidic deposition with increased atmospheric loading of sulfate and direct changes in surface water chemistry has been well established. The importance, though, of increased nitrogen (N) deposition in the episodic acidification of alpine lakes and N saturation in alpine ecosystems is only beginning to be documented. In alpine areas of the Colorado Front Range, modest loadings of N in deposition have been associated with leakage of N to surface waters. On the Colorado western slope, however, no leakage of N to surface waters has been reported. A 1995 study that included early season under-ice water samples that were not available in earlier studies showed that there is, in fact, N leakage to surface waters in some western slope basins. Under-ice nitrate (NO- 3) concentrations were as high as 10.5 μeq L-1 and only decreased to detection limits in September. Landscape type appears to be important in leakage of N to surface waters, which is associated with basins having steep slopes, thin soils, and large amounts of exposed bedrock. NO- 3 leakage compounds the existing sensitivity to episodic acidification from low acid neutralizing capacity (ANC), which is less than 40 μeq L-1 in those basins. [Key words: episodic acidification, nitrogen deposition, nitrate, alpine ecosystems, landscape type, Rocky Mountains.]  相似文献   

4.
采空沉陷湿地形成动力过程的初步研究   总被引:1,自引:0,他引:1  
因采空、沉陷和积水所形成的湿地是采矿沉陷区扰动了区域性地表水和地下水循环而产生了季节性或永久性积水而形成的一种湿地类型。从采空沉陷湿地形成的主要动力过程入手,研究其形成原因,明确其主要湿地特征。结果表明,采空积水沉陷地是在人类对地下矿层开采后,上覆岩层发生弯曲变形、断裂、位移,导致地面塌陷下沉,形成比采矿范围大得多的负地貌(低洼地);同时原有地表水系统因地表沉陷被破坏,使采矿沉陷区演变为局部汇水区,导致季节性或永久性积水;最终使其出现了沼泽化水生生态系统等特征,形成了一种新型人工湿地。  相似文献   

5.
基于Landsat-TM和MODIS的非洲水体分布格局研究   总被引:1,自引:0,他引:1  
卫星遥感是进行洲际或者全球尺度内陆水体信息提取的最有效、最为切实可行的技术手段。作为全球水资源较为匮乏的大洲,以遥感技术进行非洲内陆水体信息提取研究具有重要的应用价值。文章以2010年Landsat TM/ETM+卫星遥感影像数据为基础,辅以MODIS遥感影像,基于面向对象的分类方法,选用归一化差值水体指数(Normalized Difference Water Index,NDWI)及波段组合(Band 4/Band 2)进行水体信息提取。并根据不同气候区,选取4个典型区,监测年内水体的变化情况。结果表明:1)非洲内陆水体面积为311 479.2 km2,其中湖泊总面积为209 018.5 km2,占水体总面积的67.1%;河渠总面积64 550.1 km2,占20.7%;水库坑塘总面积37 910.7 km2,占12.2%。非洲拥有水库211个,总面积13 438.7 km2。2)撒哈拉以南的非洲是水体主要的分布区,统计分析表明约97%的水体分布在该地区。3)热带沙漠气候区湖泊面积呈减少趋势,热带草原气候区湖泊受干湿季节影响上下波动较大,热带雨林气候区和地中海气候区湖泊面积变化较小,总体上4个典型区水体面积变差系数<10%。  相似文献   

6.
The θ-S relations for the cold, saline deep and bottom waters in the Greenland and Norwegian Seas and the Polar Ocean are displayed and discussed. The differences in θ-S curves are explained by a mixing of the deep water masses and by the injection of waters from above consisting of cold dense water formed by cooling and ice formation at the sea surface and entrained warm water from the intermediate layers. Estimates of the strength of the deep water circulation are based upon the changes in θ-S curves and on some assumptions about the transformations of the Bering Strait inflow in the Chukchi Sea and on the Alaskan shelf.  相似文献   

7.
We examine some special features inherent in the formation of resources and chemical composition of the surface waters in the Eravninskaya depression. It is shown that dislocations with a break in continuity have a considerable influence on the hydrochemical behavior of the lakes. Lake Bol. Surkhebt, Lake Gunda and Lake Mal. Eravnoe will experience the greatest level of exposure to pollution caused by the operation of the Ozernoe polymetallic ore deposit.  相似文献   

8.
本文比较了从北纬30?西太平洋至南纬30?东印度洋等热带海域与南大洋至东南极普里兹湾等南极海域的大气和表层海水N2O分压分布特征,表层海水pNO2饱和异常,分析引起异常差异性的主要影响因子。南极海域普里兹湾表层水中N2O分压(pN2O)平均为311.9 ± 7.6 nL/L (14.1 ± 0.4 nM),与大气中N2O混合比(318.5 nL/L)相比显略不饱和,融冰水的输入是导致不饱和的主要原因。海气N2O通量为-0.3 ± 0.8μmol m-2 d-1。而热带海域多数表层海水中N2O饱和度异常值都高于10%,在赤道海域发现最高值达54.7%,次高值为10°N的苏禄海为31%,计算出在赤道和苏禄海的海气通量分别为~12.4 μmol m-2 d-1和~4μmol m-2 d-1。表明高纬度的普里兹湾既不是大气中N2O源也不是汇,而低纬度热带海域表现为大气中N2O的源。造成热带与南极海域海洋N2O饱和度异常的影响因素,可能低纬度的热带海域由于海气间的气体交换较弱、上升流影响强,而高纬度的南极海域由于融冰分层和强偏西风影响;而海表面风速是影响N2O的海气交换N2O通量的重要因素。  相似文献   

9.
Circulation in the Arctic Ocean   总被引:7,自引:0,他引:7  
Much information on processes and circulation within the Arctic Ocean has emerged from measurements made on icebreaker expeditions during the past decade. This article offers a perspective based on these measurements, summarizing new ideas regarding how water masses are formed and how they circulate. Best understood at present is the circulation of the Atlantic Layer and mid-depth waters, to depths of about 1700 m, which move in cyclonic gyres in the four major basins of the Arctic Ocean. New ideas on halocline formation and circulation are directly relevant to concerns regarding changes in ice thickness. The circulation of the halocline water in part mimics that of the underlying Atlantic Layer. A number of large eddies contributing to water mass transport have been observed. The circulation of freshwater from the Pacific Ocean and from river runoff has been better delineated. Circulation within the surface layer resembles the circulation of ice, but is different in several respects. Least understood is the circulation of the deepest waters, though some information is available. Recent observed changes in the surface waters and warm Atlantic Layer have been correlated with the North Atlantic Oscillation. While these changes are dramatic, the qualitative circulation pattern may not have been altered significantly.  相似文献   

10.
We provide a brief outline of the Middle Onon region and characterize the current status of the soils, vegetation and surface waters. We examine the environmental consequences of development of tin and gold deposits in the region, and suggest some avenues for recultivation of technogenically disturbed landscapes.  相似文献   

11.
Many informal communities within urban areas in sub-Saharan Africa are heavily reliant on shallow hand-dug wells for water, but these are vulnerable to contamination from a range of sources. This paper assesses the heavy metal contamination and total coliform risk of unprotected shallow wells in Ndola, Zambia – a city struggling with contaminated surface waters from both bacteriological and potential mining waste products. One hundred and twenty three shallow wells were sampled across the Ndola, and these encompassed the three main lithologies of the city. All wells lacked an internal casing, however, some wells did have covers and/or pavements surrounding the wells, albeit of dubious efficacy. Despite the lack of protection, the quality of water used abstracted from these wells generally met the World Health (WHO) guidelines for heavy metals (with the exception of Al) and total coliforms (although, this was highly variable). The quality of shallow well water varied across Ndola relative to the underlying geology, where total recoverable concentrations were typically lowest in granite-gneiss. Dissolved load concentrations were lowest in dolomite-limestone, highlighting the role of aquifer geology in acting as a buffer against metal toxicity. Our study illustrates that shallow wells, within the appropriate geological units, may provide a safe and reliable source of drinking water. Well protection is, however, needed to ensure that the proliferation of shallow well use does not lead to regional degradation of the groundwater resource. There is an immediate need to invest in promoting internal well casing during the construction of shallow wells, concomitant with investment and education into protecting wells at the surface, despite the current relatively low level of contamination in wells without protection.  相似文献   

12.
Eva Falck 《Polar research》2001,20(2):193-200
Measurements of nitrate and phosphate taken in the Northeast Water Polynya (NEWP) during the summer of 1993 have been used to identify the contribution of waters of Atlantic and Pacific origin in the polynya. Since waters from the northern Pacific exhibit a deficit in nitrate relative to phosphate due to denitrification in low oxygen waters, the relationship between nitrate and phosphate can be used to distinguish between oceanic waters of Pacific and Atlantic origin. The Pacific Water enters the Arctic Ocean through Bering Strait and flows along the northern coasts of Alaska and Canada. Some of this water exits through Fram Strait and may therefore enter the polynya which is situated above the continental shelf off the north-eastern coast of Greenland. Compared to data from the Greenland Sea, which only show a N–P relationship of typical Atlantic Water, the data from the Northeast Water Polynya show that the upper waters of the polynya bear a clear signal of waters of Pacific origin. In the surface mixed layer an average of about 90% is found to have Pacific N–P characteristics. Below the surface mixed layer the amount of Pacific derived water decreases through the halocline and from about 150 m to the bottom only typical Atlantic Water is found.  相似文献   

13.
We have examined the regularities of change in the relationship between amounts of organic and mineral components in the surface waters of the Lake Baikal watershed basin. We calculated the contributions from the dissolved matter sources in the surface waters: organic and mineral matter of soils, and atmospheric deposition. Components-indicators of matter sources have been revealed. By analyzing the correlations between components and sources, we identified the main processes that are responsible for formation of chemical composition of the waters.  相似文献   

14.
The Secretary of the Interior through appropriate staff can inquire into the validity of mining claims through the Act of April 25, 1812 (R.S. 453; 43 USC 2). Validity examinations are also authorized by the Act of July 23, 1955 (USC 601), for management over surface resources of mining claims located prior to the Act [Adams v. United States, 318 F2d 861 (9th Cir 1963).] Validity examinations are normally made in response to one of two circumstances: (1) to process a mineral patent application; or (2) to resolve a conflict between the mining claim and some other use of the land. Federal employees charged with the management of Federal lands have the right and authority to challenge the validity of mining claims for any reason [Estate of Melvin E. Viles, 126 IBLA 162, 164 (1993).] A validity examination of an unpatented mining claim by a Federal Government minerals examiner is to verify or refute a discovery on that claim. The mineral examiner makes a recommendation as to whether a claim is valid or invalid. If a discovery cannot be verified within the limits of the claim, the examiner will normally recommend that the government contest the claim. Concepts for making validity examinations on mining claims are here given. Many mineral deposits are unique and it is important that the mineral examiner use their initiative and adopt whatever detailed procedures may be required.  相似文献   

15.
葛晓东  李振山 《中国沙漠》2009,29(3):404-408
以奈曼旗作为案例研究地,以1987年和2002年的Landsat/TM影像为基本数据源,按与水体的空间距离,对水体周边区域的裸沙地面积百分比进行分地带统计。该过程通过ArcGIS平台下的缓冲区分析完成。结果发现,奈曼旗的沙漠化程度的空间差异与地表水的空间分布关系密切。总体来讲,奈曼旗境内主要水体周边的沙漠化程度随空间距离变化有明显的差异,从水体边界开始,随着与水体空间距离的增加,裸沙地面积百分比值不断升高,并在距离湖泊水库1 km处、距离教来河北段2 km处、教来河南段6 km处和老哈河7 km处,裸沙地面积百分比值达到极大。在更远距离,老哈河、舍力虎水库、西湖水库周边的裸沙地面积百分比值随距离增加而迅速下降,教来河北段和教来河南段周边的裸沙地面积百分比值随距离增加呈缓慢下降趋势,孟家段水库周边的裸沙地面积百分比则略有波动,从5 km距离后呈迅速下降趋势。按水体的空间格局划分,奈曼旗的沙漠化程度被划分为4个不同程度的区域。以上现象说明,地表水及其利用在奈曼旗的沙漠化发展过程中起到了非常重要的作用。  相似文献   

16.
We discuss the changes in hydrological characteristics of water bodies caused by freshwater withdrawals to meet the interests of various users on the territory of the Syunik Province of the Republic of Armenia. An analysis is made of the possibilities of combining the water withdrawal for mining enterprises and for agriculture. The problems with water supply of settlements located on this territory are highlighted. The temporal dynamics of water withdrawals is presented for separate rivers as well as its relationship with the minimum and ecological flow. It is found that the anthropogenic load on water bodies is more clearly pronounced in the case of a degradation of the quality of water resources as a result of the industrial waste water diversion, and wash-out of pollutants from the territory of enterprises during floods and in the case of emergency input of wastes from tailings pools, rock spoil heaps and waste storage areas. Results of these authors’ observations, data of routine observations and material from published sources were used in analyzing the water quality in the rivers of the Syunik Province. We calculated the coefficients of ecological quality and determined the river water quality classes according to physicochemical and biological indicators. Assessments of the river water quality class were made in accordance with the methodology of Directive 2000/60/EC. We identified the main pollutants that are responsible for the water quality class, and the factors of impact on natural waters governing the ecological status of water bodies. A comprehensive analysis is made of the intensity of anthropogenic impact on surface waters. The ecological status of water bodies is determined. Spatial changes in the quality indicators of the water of the region’s main rivers are demonstrated. Special emphasis is placed on the need to implement immediate measures to improve technological processes and bring the operation of enterprises into compliance with ecological normative standards.  相似文献   

17.
本文采用发酵法对菲尔德斯半岛南部近海水域表层中粪大肠菌群数量进行了初步调查。结果表明 ,在近岸表层海水中 ,粪大肠菌群检出数密度最大的 40个 /升 ,一般是 2 0个 /升 ,密度最小的小于 2 0个 /升 ,后者占多数站位。排污口潮间带 1月份粪大肠菌群检出数 40个 /升 ,3月份 2 80 0个 /升。粪大肠菌群的分布 ,离岸越近数量越高 ,同频繁的人类活动有密切关系。由此看来菲尔德斯半岛南部近岸水体已受生活污水污染 ,尚属轻度污染。但排污口潮间带的污染趋势应引起我们重视  相似文献   

18.
贵州省南北盘江流域地下水污染现状研究   总被引:1,自引:0,他引:1  
贵州省境内的南北盘江流域集中了省内大量煤矿、煤化工企业,流经该流域的地表水均受到不同程度的污染,由于地下水与地表水水力联系极为密切,直接接受地表水的补给,地下水在一定程度上也遭到了污染,综合运用单项指数法和综合指数法对地下水污染现状进行评价,把该流域地下水污染现状分为4个区,找出了地下水的主要污染物和污染规律。  相似文献   

19.
云南边境地区土地利用/覆盖变化及环境效应分析   总被引:2,自引:3,他引:2  
采用遥感和GIS一体化技术,利用1976年的MSS和2004年的TM两个时期的遥感影像数据对云南边境地区的土地覆盖动态变化进行监测,并对变化的时空特征进行分析。结果表明土地覆盖现状以森林和裸岩地为主,其次是耕地和水域。土地利用/覆盖变化主要发生在林地、水域、耕地和裸地四大地类中,林地减少了6.95%,水域减少了2.08%;耕地增加了4.04%,裸地增加了3.67%。并对土地变化所引起资源和环境问题及其驱动因素进行了初步的探讨和分析。  相似文献   

20.
本文以伊金霍洛旗纳林陶亥镇煤矿集中区土壤性质为研究对象,通过野外调查取样和室内分析,对矿区土壤性质空间变化进行了研究,并运用主成分分析法对矿区土壤性质进行了综合评价。结果表明:内蒙古伊金霍洛旗煤矿开采对土壤性质影响显著。土壤性质随矿区影响半径的增加,采煤活动对其影响程度逐渐降低,且表层土壤受到的扰动最为强烈。相比矿区外部,矿区内部土壤受到影响较大,深层与表层土壤稳定性较差,而矿区外部土壤受到影响较小,土壤肥力流失随土层深度的增加而减缓。  相似文献   

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