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1.
Changes in glacial lakes and the consequences of these changes, particularly on the development of water resources and management of glacial lake outburst flood(GLOF) risk, has become one of the challenges in the sustainable development of high mountain areas in the context of global warming. This paper presents the findings of a study on the distribution of, and area changes in, glacial lakes in the Koshi basin in the central Himalayas.Data on the number of glacial lakes and their area was generated for the years 1977, 1990, 2000, and 2010 using Landsat satellite images. According to the glacial lake inventory in 2010, there were a total of 2168 glacial lakes with a total area of 127.61 km~2 and average size of 0.06 km~2 in the Koshi basin. Of these,47% were moraine dammed lakes, 34.8% bedrock dammed lakes and 17.7% ice dammed lakes. The number of glacial lakes increased consistently over the study period from 1160 in 1977 to 2168 in 2010, an overall growth rate of 86.9%. The area of glacial lakes also increased from 94.44 km~2 in 1977 to 127.61 km~2 in 2010, a growth rate of 35.1%. A large number of glacial lakes in the inventory are small in size(≤ 0.1km~2). End moraine dammed lakes with area greater than 0.1 km~2 were selected to analyze the change characteristics of glacial lakes in the basin. The results show that, in 2010, there were 129 lakes greater than 0.1 km~2 in area; these lakes had a total area of 42.92km~2 in 1997, increasing to 63.28 km~2 in 2010. The distribution of lakes on the north side of the Himalayas(in China) was three times higher than on the south side of the Himalayas(in Nepal).Comparing the mean growth rate in area for the 33 year study period(1977-2010), the growth rate on the north side was found to be a little slower than that on the south side. A total of 42 glacial lakes with an area greater than 0.2 km~2 are rapidly growing between 1977 and 2010 in the Koshi basin, which need to be paid more attention to monitoring in the future and to identify how critical they are in terms of GLOF.  相似文献   

2.
Laboratory and field experiments on the dissolution of oil showed that the quantity of the dissolvedoil component in the seawater depends on its solubility, concentration in the pertroleum, and theenvironmental conditions. The vertical oil concentration in calm sea decreases exponentially with depth.The vertical diffusion coefficients and dissolution constants of the N-pareffin from C_(12) to C_(21), totaliso-paraffin, cycle-paraffin and aromatic components in calm sea were calculated, and the oil dissolution in-to seawater was determined to be about 0.52% in 48 h for No. 0 light diesel oil.  相似文献   

3.
The area of the intermontane basins in the Xuefeng Mountain region is 4,000 km2. These basins are the most favourable area for agriculture in the mountainous region. Unfortunately, in each basin the eco-environment has gradually worsened because of the irrational utilization of natural resources. A rational model of agro-ecologic- economic system of intermontane basin must be formed so as to exploit and utilize rationally the natural resources. The intermontane basins may be divided into 3 ecologic belts of agriculture. Here are some ecologic-economic problems in the development: The resources of the outer mountains lie waste, but the valley basins in centre are over-development; the low mountains and hillocks are cultivated for dry crops so that the water and soil losses are serious and the natural disasters are frequent. Therefore, the agro-economic, agro-biologic and eco-environmental subsystems form a complete agro-ecologic-economic system of intermontane basins. Developing rationally the resources  相似文献   

4.
Wetlands are sensitive to climate change, in the same time, wetlands can influence climate. This study analyzed the spatio-temporal characteristics of wetland change in the semi-arid zone of Northeast China from 1985 to 2010, and investigated the impact of large area of wetland change on local climate. Results showed that the total area of wetlands was on a rise in the study area. Although natural wetlands(marshes, riparians and lakes) decreased, constructed wetlands(rice fields) increased significantly, and the highest increase rate in many places exceeded 30%. Anthropogenic activities are major driving factors for wetland change. Wetland change produced an impact on local climate, mainly on maximum temperature and precipitation during the period of May–September. The increase(or decrease) of wetland area could reduce(or increase) the increment of maximum temperature and the decrement of precipitation. The changes in both maximum temperature and precipitation corresponded with wetland change in spatial distribution. Wetland change played a more important role in moderating local climate compared to the contribution of woodland and grassland changes in the study area. Cold-humid effect of wetlands was main way to moderating local climate as well as alleviating climatic warming and drying in the study area, and heterogeneity of underlying surface broadened the cold-humid effect of wetlands.  相似文献   

5.
The effects of natural fish oil,DHA oil and soybean lecithin in microparticulate diets on stress tolerance of larval gilthead seabream(Sparus aurata)were investigated after 15 days feeding trials.The tolerance of larval gilthead seabream to various stress factors such as exposure to air(lack of dissolved oxygen),changes in water temperature(low)and salinity(high) were determined.This study showed that microparticulate diet with natural fish oil and soybean lecithin was the most effective for in-creasing the tolerance of larval gilthead seabream to various stresses,and that microparticulate diet with natural fish oil and palmitic acid(16:0)was more effective than microparticulate diet with DHA oil and soybean lecithin.  相似文献   

6.
The relatively rapid recession of glaciers in the Himalayas and formation of moraine dammed glacial lakes(MDGLs) in the recent past have increased the risk of glacier lake outburst floods(GLOF) in the countries of Nepal and Bhutan and in the mountainous territory of Sikkim in India. As a product of climate change and global warming, such a risk has not only raised the level of threats to the habitation and infrastructure of the region, but has also contributed to the worsening of the balance of the unique ecosystem that exists in this domain that sustains several of the highest mountain peaks of the world. This study attempts to present an up to date mapping of the MDGLs in the central and eastern Himalayan regions using remote sensing data, with an objective to analyse their surface area variations with time from 1990 through 2015, disaggregated over six episodes. The study also includes the evaluation for susceptibility of MDGLs to GLOF with the least criteria decision analysis(LCDA). Forty two major MDGLs, each having a lake surface area greater than 0.2 km2, that were identified in the Himalayan ranges of Nepal, Bhutan, and Sikkim, have been categorized according to their surface area expansion rates in space and time. The lakes have been identified as located within the elevation range of 3800 m and6800 m above mean sea level(a msl). With a total surface area of 37.9 km2, these MDGLs as a whole were observed to have expanded by an astonishing 43.6% in area over the 25 year period of this study. A factor is introduced to numerically sort the lakes in terms of their relative yearly expansion rates, based on their interpretation of their surface area extents from satellite imageries. Verification of predicted GLOF events in the past using this factor with the limited field data as reported in literature indicates that the present analysis may be considered a sufficiently reliable and rapid technique for assessing the potential bursting susceptibility of the MDGLs. The analysis also indicates that, as of now, there are eight MDGLs in the region which appear to be in highly vulnerable states and have high chances in causing potential GLOF events anytime in the recent future.  相似文献   

7.
The growing attention on urban tourism was very widespread. There are two angles to study urban tourism: supply-side and demand-side. And the supply-side of the tourism remains very important. The RBD (Recreation Business District) is a useful framework to understand the components of urban tourism and how they fit together. The paper begins with a review on the RBD and the spatial structure of tourism in urban areas and then attempts to develop a more general understanding of the spatial structure evolution of RBDs in a tourist-historic city—Suzhou. The spatial structures and functions of the RBDs in Suzhou are examined, based on field observations, interviews with city officials and industry leaders, and a review of available documents. The urban tourism of Suzhou has developed in a range of contexts, that various types of RBDs have emerged as a result of different urban development strategies. The spatial structure has evolved from the past “Single-cored Structure“ to “Double-cored Structure“ at present, and then to “Chain Structure“ in the future. The spatial form and evolution of RBD in Suzhou are closely relative with its urban spatial expansion. Urban area dispersal is the prerequisite of the emergence of the RBD. Planning and constructing the RBD becomes a new impetus to urban growth or renewal. Finally, a number of strategies for planning and developing the RBD in Suzhou are suggested. The different RBDs should adopt different strategies.Intensification can be the possible strategy for the RBDs in the ancient city. Accreting with the urban theme park or engrafting on the Jinji Lake is suggested respectively for the RBD in the Suzhou New District and the Suzhou Indus-trial Park.  相似文献   

8.
The Loess Plateau is one typical area of serious soil erosion in the world. China has implemented ′Grain for Green′(GFG) project to restore the eco-environment of the Loess Plateau since 1999. With the GFG project subsidy approaching the end, it is concerned that farmers of fewer subsidies may reclaim land again. Thus, ′Gully Land Consolidation Project′(GLCP) was initiated in 2010. The core of the GLCP was to create more land suitable for farming in gullies so as to reduce land reclamation on the slopes which are ecological vulnerable areas. This paper aims to assess the effect of the GLCP on soil erosion problems by studying Wangjiagou project region located in the central part of Anzi valley in the middle of the Loess Plateau, mainly using the revised universal soil loss equation(RUSLE) based on GIS. The findings show that the GLCP can help to reduce soil shipment by 9.87% and it creates more terraces and river-nearby land suitable for farming which account for 27.41% of the whole study area. Thus, it is feasible to implement the GLCP in places below gradient 15°, though the GLCP also intensifies soil erosion in certain places such as field ridge, village land, floodplain, natural grassland, and shrub land. In short, the GLCP develops new generation dam land and balances the short-term and long-term interests to ease the conflicts between economic development and environmental protection. Furthermore, the GLCP and the GFG could also be combined preferably. On the one hand, the GFG improves the ecological environment, which could offer certain safety to the GLCP, on the other hand, the GLCP creates more farmland favorable for farming in gullies instead of land reclamation on the slopes, which could indirectly protect the GFG project.  相似文献   

9.
According to the theory of sustainable development, the current situation and existent problemsoftheexploita-tion of water resources were analyzed in this paper. The results show that the contradiction between supply and demandof water resources is continually aggravating, water pollution is increasingly serious, water environment is worse, theover-extraction area of the underground water is expanding and water crisis stands out gradually, so it is imperative underthe situation to actualize the sustainable exploitation strategies of water resources. It is necessary for sustainable utilizingwater resources to introduce the model of sustainable utilization of water resources the model of wealth transferring be-tween the generations of water resources, establish water-saving society system and water market, form technology sys-tems, management systems and evaluation systems for many sorts of water resources, improve the utilization ratio of waterresources, transform waste water into resources and maintain and restore the water space of water environment.  相似文献   

10.
In this paper,we compared the normalized radar cross section in the cases of oil spill,biogenic slicks,and clean sea areas with image samples made from 11-pixel NRCS average,and determined their thresholds of the NRCS of the synthetic aperture radar. The results show that the thresholds of oil and biogenic slicks exhibit good consistency with the corresponding synthetic aperture radar images. In addition,we used the normalized radar cross section of clean water from adjacent patches of oil or biogenic slicks areas to replace that of oil or biogenic slicks areas,and retrieve wind field by CMOD5.n and compare wind velocity mending of oil and biogenic slicks areas with Weather Research and Forecasting modeled data,from which the root mean squares of wind speed(wind direction) inversion are 0.89 m/s(20.26°) and 0.88 m/s(7.07°),respectively. Therefore,after the occurrence of oil spill or biogenic slicks,the real wind field could be repaired using the method we introduced in this paper. We believe that this method could improve the accuracy in assessment of a real wind field on medium and small scales at sea,and enhance effectively the monitoring works on similar oil or biogenic slicks incidents at sea surface.  相似文献   

11.
秃尾河流域表生生态环境现状评价   总被引:1,自引:0,他引:1  
以地下水为主线,开展流域表生生态环境评价的方法研究尚处于发展之中。以秃尾河流域为例,紧紧围绕地下水这条主线,在建立流域表生生态环境递阶层次评价指标体系和评价标准的基础上,尝试采用模糊综合评判方法与模糊迭代自组织数据分析技术相结合,开展流域表生生态环境现状评价。评价结果表明,流域生态环境现状总体较好,其中盖沙丘陵区、河流源头和河谷阶地区及沙漠区是水资源与生态环境保护的重点,这些研究为评价生态环境脆弱区水资源开发利用对表生生态环境的影响以及保护流域水资源与生态环境提供了科学依据。评价结果与流域生态环境实际更为吻合,规律性更明显。  相似文献   

12.
数字油田是解决当前油田建设中数据冗余的一个有效途径。本文结合大庆油田勘探、开发与建设过程中存在的数据量大、共享困难等问题,对大庆油田的基于统一共享平台的各种空间数据及其他非空间数据共享问题进行了分析,并给出了基于ArcGIS产品的油田数据管理与共享问题的解决方案。  相似文献   

13.
临沂市蒙阴县地处沂蒙山区,地形起伏大,山区峰高坡陡,矿产资源较丰富,近年来,受矿产开发、地下水开采、山区综合开发利用,交通与水利建设以及不利地质条件影响,局部地段地质灾害频繁发生,根据蒙阴县台上铁矿区的地质环境条件,结合矿山地质环境问题的实地调查,在综合分析的基础上进行影响评估,并有针对性地提出了恢复治理措施。  相似文献   

14.
经济的快速发展, 对砂石料的需求巨大, 海砂的开发成为当前的热点。琼州海峡东口海砂资源丰富, 资源潜力概算可达数十亿方。依据前期调查数据, 选取含泥量、含砂量、粒级、海砂厚度、水深和离岸距离6类指标, 采用层次分析法, 构造判断矩阵计算评价因子的权重, 运用ArcGIS空间分析功能进行叠加, 对琼州海峡东口的海砂进行了开发适宜性评价。结果表明: 经计算将研究区分为开发适宜性好、较好、中等、较差、差5个等级, 其中浅滩区域海砂规模大、质量好、水深浅和开采环境影响小, 其开发适宜性最佳。分析了不同的指标对海砂开发适宜性的影响, 在浅滩区, 厚度和含砂量指标贡献较大; 在近岸海湾, 环境影响是主要因子; 在琼州海峡深槽区, 水深条件则成为海砂开发的主要限制条件。根据海砂资源的特点, 建立了以资源自然属性、开发技术条件、生态环境影响和行政管理为主要因子的海砂开发利用适宜性评价体系, 具体工作可选取不同的指标开展评价。研究结果可以为研究区海砂的开发利用和其他区域海砂开发适宜性评价提供参考。   相似文献   

15.
城市发展对水体多方面要素产生了巨大影响,尤其是对水资源丰富的城市,迫切需要开展相关监测研究。研究以武汉市为例,通过梳理国内外相关研究以及武汉水体保护政策,提出融合水体面积、水质、水体景观、滨水区生态环境4个方面要素的分析技术路线以更为全面的反映城市尺度的水体时空演变特征,具体的,利用随机森林模型基于1979—2019年遥感影像获取武汉67个重点水体信息,并以此获取水体面积和水体景观的变化特征;同时,通过梳理多年水质监测数据分析水质变化特征;另外,基于遥感生态指数(Remote Sensing Ecological Index, RSEI)分析滨水区生态环境变化;最后,采用多尺度地理加权回归模型(Multi-scale Geographically Weighted Regression, MGWR)对重点水体面积变化的影响因素研究,希冀为政府制定差异化的水体保护政策提供科学支撑,并为其他地区水体的多要素分析提供有益借鉴。结果表明:① 武汉市水体面积呈下降趋势,水体总面积、重点水体面积分别减少10.75%及13.12%,中心城区及郊区水体变化存在显著差异;② 水体景观呈退化趋势,周长面积分维数、平均斑块面积、聚合指数及结合指数分别减少了6.43%,79.35%,1.55%及10.94%;③ 重点水体水质总体呈恶化趋势,其中江河及水库多数常年为III类及以上水体,中心城区湖泊多为V类及以下水体,郊区湖泊多为IV类及V类水体;④ 中心城区及郊区滨水区遥感生态指数(RSEI)分析表明滨水区生态环境呈恢复态势,其中中心城区滨水区平均RSEI增长了14.29%;⑤ MGWR分析表明,自然气象因素中,相对湿度的增加对江夏区湖泊恢复影响更为显著,降水对水面较小的水体恢复影响更为显著;社会经济因素中,各行政区GDP的增加有助于水体恢复,对中心城区、黄陂及新洲的水体保护影响更为显著;滨水缓冲区内不透水面占比(IS)的增加导致大多数水体面积的减少,然而,对于少数重点修复水体,IS增加是受相关保护政策影响,IS增加有助于这些水体恢复。  相似文献   

16.
北部湾北部海上油田的开发工作始于50年代,60~70年代作了大量地质工作。改革开放后,油气勘查取得突破性进展。累计发现油气构造6个,含油面积超过40km2,石油地质储量约4亿t,已开发油田2个,揭开我国南方油气资源开发序幕  相似文献   

17.
本文论述了跨断层形变测量近场信息开发利用的必要性以及可供开发的新信息资源的主要内容,研究了断层列线阵信息开发的理论依据和可能的图象,给出了新信息资源利用的经验合成公式。以金县短水准为例,结果表明,近场新信息资源的开发利用(合成),使其地震预报效能较传统方法有了较大幅度的提高,说明近场新信息的开发利用是提高前兆手段地震预报效能经济而有效的方法之一。  相似文献   

18.
I.INTRODUCTIONThearidlandinNorthwestChina,richinlight,heat,landandmineralresources,isoneofthebiggestpotentialregionsforeconomicdevelopmentinthefuture.Itischaracterizedbydroughtclimate,scarceprecipitationandthereisnoagriculturewitholltirrigation(Liu,1980).Waterisnotonlythemostvaluablenaturalresources,butalsoveryimportantenvironmentalfactorinthisarea.Theoasesandwaterresourcesforhumansurvivalanddevelopmentaredistributedmainlyintheinlandriverbasins.Atpresentexploitationandutilizationofwater…  相似文献   

19.
山东省地热资源类型多且分布广,资源储量丰富,开采条件好,是名副其实的地热资源大省。本文采用逐井调查方法,对山东省范围内地热井数量、开发利用方式、地热流体开采量、地热井与油气资源矿业权重叠等进行了调查,对开发利用过程中存在问题进行研究分析。截至2020年底,全省共有地热井1862眼,主要包括洗浴与疗养模式、洗浴与疗养兼养殖与种植模式、养殖与种植模式、供暖兼洗浴模式四种模式;全省地热流体开采总量约1.405×108m3/a,其中供暖开采量约1.216×108m3/a,供暖面积约4060×104m2;康乐用开采量约0.166×108m3/a,养殖及其他用开采量约0.068×108m3/a。对油气资源矿业权(采矿权、探矿权)与地热井重叠进行论述,分析了地热开发利用过程中存在的问题,为今后全省地热资源的开发利用提供了依据。  相似文献   

20.
孤东油田植被演化遥感分析   总被引:2,自引:0,他引:2  
本文利用从1984-2001年多时相的TM和ASTER等遥感数据,对孤东油田近二十年来的植被演化规律进行研究,分析油田开发的不同阶段对植被的影响。结果表明,在油田开发初期,植被遭到毁灭性的破坏,使区域生态环境严重恶化。油井建成后,被破坏的生态环境逐步得到恢复,并向着顺向演替的方向发展,目前孤东油田的生态环境正在向着良性循环方向发展。  相似文献   

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