吉林中部平原区浅层地下水温度对全球气候变暖的响应

水温变化除引起水的多种物理性质的变化外, 还会引起水化学反应速度等方面的变化. 以吉林中部平原地区为例, 对影响浅层地下水温因素的分析发现, 研究区浅层地下水温变化的本质原因是受全球气候变化的影响, 降水量的减少以及地下水位的下降对浅层地下水温受气候变化的影响起到削减作用. 通过对全区近200眼地下浅层观测井水温的多年变化分析, 发现在研究区气温近20 a来升高(约1.5 ℃)的影响下, 浅层地下水温从1978年的7 ℃左右上升到2001年的8.3 ℃, 在20余年间水温升高约1.3 ℃     

淮北平原浅部地下水换热系统适宜性评价

安徽省淮北平原广泛分布着宜于利用的浅层地热能,具有以地下水换热方式开发利用的前景。本文利用层次分析(AHP)法,以MapGIS、Access为平台,评价安徽省淮北平原浅部(评价深度50m)地下水换热系统适宜性。参考国内外最新研究成果,结合评价区地质环境特点,在评价因素分类、等级划分和评价指数分级等方面进行了深入研究,评价结果体现了浅部孔隙水系统的基本特点,具有较强的规律性。     

滹滏平原漏斗区地下水溶解性总固体演变特征研究

为揭示滹滏平原漏斗核心区地下水溶解性总固体（TDS）增大对水位下降的响应特征以及驱动TDS增大的主要化学组分,应用地学数理统计分析、时间序列异变分析和GIS空间特征分析技术,分析了近50年（1972—2017）研究区地下水水位埋深、TDS及化学组分变化特征。结果表明：（1）随着水位降幅变化,地下水TDS增幅具有阶段性变化特征,在漏斗形成初期（1972—1980年）,地下水水位年均降幅最大,TDS年均增幅也最大;中期（1981—2000年）地下水水位年均降幅最小,TDS年均增幅也最小;末期（2001—2017年）地下水水位年均降幅居中,TDS年均增幅也居中。（2）随着水位埋深增大,漏斗核心区地下水水位埋深大小对TDS增大影响呈递减效应。漏斗形成初期水位埋深9.10～23.20 m,中期水位埋深13.40～42.28 m,末期水位埋深21.41～50.29 m,漏斗核心区地下水水位年均降幅每增大1.0 m条件下,TDS年均增幅分别增大21.96 ,13.54 ,12.32 mg/L。（3）自初期、中期至末期,地下水中Na+、${\rm{SO}}_4^{2-} $含量增幅占TDS增幅的比率呈不断增大特征,为漏斗核心区TDS增大的主要影响因素。但末期Ca2+、Mg2+、${\rm{HCO}}_3^- $和Cl−含量增幅占TDS增幅的比率合计仍达65.88%,对漏斗核心区地下水TDS增大仍然发挥至关重要的作用。     

基于TerraSolid的平原地区点云数据滤波方法

Terra Solid是处理机载激光雷达数据的常用软件。本文介绍了用Terra Solid软件对点云数据进行滤波的方法,解释了滤波过程中各参数的含义,通过实验比较了不同的参数设置对平原地区滤波结果的影响,最后,提出了对平原地区点云数据进行滤波的方案。     

A historical perspective of the morphological evolution in the lower Ebro river

 The morphological evolution, hydrodynamics and sediment dynamics of the lower Ebro are studied from historical and current data in order to determine the main changes that have governed the evolution of the Ebro channel near the river mouth during the last few centuries. The evolution of the mouth of this river during the last 2000-years, from an estuary to a delta, is interpreted as a process that has been accelerated by human land management. However, an inverse trend has been observed during recent decades: (1) the river mouth has been affected by erosion due to a drastic decrease in the river sediment discharge, and (2) the lower Ebro tends to evolve towards a quasi-permanent salt-wedge estuary as a consequence of the decrease in the river water discharge. Freshwater and sediment discharge decreases are mainly related to intense river water management during this century. The salt wedge favours erosion in the river banks, widening the river channel and causing an aggradational trend in the lower Ebro. Accretion-erosion rates and the sediment budget in the river mouth are estimated for different conditions. Received: 13 November 1995 · Accepted: 17 June 1996     

莱州湾南岸平原浅埋古河道带研究

菜州湾海岸平原在埋深６０ｍ内的浅埋古河道带,可分弥河、潍河和白浪河３个系统,它们大都呈掌状、放射状分布,并与其所属诉冲洪积扇范围相吻合,该区古河道的形成和发育是新构造运动和古气候环境演变的结果。自晚更新世晚期以来,该区有６期古河道发育,其中玉木早冰期古河道和玉木主冰期古河道的砂体沉积粒度粗、连通性好、分布广,即是富水性强、水质好的淡水含水层,又是该区海（咸）水入侵的主要通道,控制在线积粒度粗、连通     

Quality evaluation of groundwater in the North China Plain

This paper presents a method combining single-indicator comprehensive evaluation and influence factor identification to measure groundwater quality. This method not only reflects groundwater quality classification with clear physical significance, but also divides the possibilities of man-made pollution in regional groundwater. The paper selects 6 063 representative groundwater wells in the North China Plain to evaluate 49 groundwater inorganic and organic index and comes to a conclusion: Controlled by geological environment and hydrogeological conditions, the groundwater quality in the North China Plain deteriorates from the bottom of maintain to coastal area, with Class I to III groundwater decreasing from 49% to 3.9% while Class V groundwater increasing from 21% to 86.9%; the quality of deep groundwater is better than that of shallow groundwater; the contribution rate of manganese, total hardness, total dissolved solids and iodide in shallow groundwater to over-III type water exceeds 50%; the contribution rate of nitrite in pollution index reaches 20%; while heavy metal and organic indexes have limited impact on regional groundwater quality. The North China Plain is an important economic area in China. Over decades, it has witnessed intense human activities, and water resource quantity demanded has been far greater than quantity supplied. Due to scarce surface water resource, groundwater becomes the pillar supporting regional economic development. This has led to increasing groundwater exploitation and development. According to statistics, the exploitation degree of shallow groundwater reaches 105% in the North China Plain and 118% in the Hebei Plain; the exploitation degree of deep groundwater reaches 143% in the North China Plain and 163% in the Hebei Plain. The serious over-exploitation of groundwater brings various geological environmental problems, with the worsening of groundwater quality being a typical one. Besides impact brought by human activities, the poor quality of natural water in the North China Plain is also an important factor. Therefore, to understand the current regional groundwater quality situation and to master influence factors and influence degree can provide reliable scientific protection for regional economic development.     

Early warning research on salt-alkalization desertification in western Songnen Plain

Desertification is an environmental issue in the world. The salt-alkalization desertification land area formed by both primary and secondary salt-alkalization has extended in a large scale, which has become a significant eco-environmental problem. Based on the characteristics of eco-environment and the situation ofdesertification in western Songnen plain, this paper reports the analyzes of its formation in background and cause. An early warning system on the salt-alkalization desertification is established and the GIS technology is used to abstract the information of desertification evaluation index. Supported by the integrated technology of the GIS and ANN, the orientation and quantitative result of desertification are gained, which is helpful to the eco-environment protection and resource development in western Songnen Plain.     

射阳湖历史变迁研究

射阳湖是苏北历史上著名的大湖。早全新世因受海侵影响,本区是里下河浅水海湾的一部分;中全新世时,由于西冈等岸外砂堤的形成,本区成为古泻湖,后因海岸东迁,淡水冲灌,古泻湖逐渐演变为淡水湖。1128年黄河夺淮后,大量泥沙进入湖区,湖区淤积迅速,成为沼泽型湖泊,加之人类活动因素的显著影响,射阳湖逐渐演变为里下河平原的一部分。     

深井填砾工艺关键技术探讨

在河北平原新近系地热井施工时采用填砾工艺具有防砂、稳定孔壁的优点,但具有一定的施工难度。通过实践应用提出了管孔径级配方案,总结了终孔替浆工艺,分析并论证了填砾数量计算方法、填砾速度的确定原则及静水填砾方法的可行性。