华北平原地下水动态及其对不同开采量响应的计算——以河北省栾城县为例

自从20世纪60年代大规模开采地下水以来,栾城县的地下水位以每年大约0.65 m的速度下降.降雨量的减少、农业产量的大幅度提高、种植结构的变化以及上游水利工程的修建,都与地下水位的下降有着密切联系.利用Visual Modflow软件,在分析该县水文地质条件与水资源利用的前提下,运用三维地下水流模型,通过有限差分方法对栾城县的地下水系统进行了模拟,结果表明:5个观测孔的地下水位计算值与实测值拟合程度很好,模拟出的地下水流场与实际情况基本一致.利用掌握的水文地质资料,进行参数分区,通过实测资料的校正、调参,模拟出各分区参数值.利用校正后的数学模型,对栾城县地下水对不同开采量的响应进行了计算,结果如下:在现状农业开采量1.01×108m3基础上分别减少14%(0.14×108m3)、29%(0.29×108m3)和增加29%(0.29×108m3)的情况下,到12月份5个观测孔的平均地下水位分别比现状地下水位上升了0.33 m,0.64 m和下降了0.45 m.     

Groundwater regime and calculation of yield response in North China Plain: a case study of Luancheng County in Hebei Province

The groundwater table has been declining at a rate of 0.65 m/yr in Luancheng County since large scale groundwater extraction carried out in the 1960s. The drop of precipitation, substantial increase in agricultural output, variations of crop planting structure and construction of water conservancy projects in the headwater area all tie up with the decline of the groundwater table. On the basis of analyzing the hydrogeological conditions and the water resources utilization of Luancheng County, a three-dimensional groundwater flow model was developed to simulate the county’s groundwater flow through finite-difference method using Visual Modflow software. We divide the research field into four parts after analyzing the hydrogeological condition. Based on parameter calibration and adjustment using measured data, the hydraulic conductivity and specific yield were simulated. Using the calibrated model, we analyze the agricultural water saving potentiality and its influence on the groundwater. The results are as follows: (1) if we decrease the amount of water extracted by 0.14xl0⁸ m³, the average groundwater table of the five observation wells in December will rise by 0.33 m; (2) if we decrease the water by 0.29x 10⁸m³, the average groundwater table of the five observation wells in December will rise by 0.64 m; and (3) if we increase the water by 0.29 x 10⁸m³, the average groundwater table of the five observation wells in December will decline by 0.45 m. So we can draw a conclusion that controlling the agricultural water use is an important way to prevent the decline of groundwater table.     

Impacts of land use changes on groundwater resources in the Heihe River Basin

Land use and land cover changes have a great impact on the regional hydrological process. Based on three periods of remote sensing data from the 1960s and the long-term observed data of groundwater from the 1980s, the impacts of land use changes on the groundwater system in the middle reach of Heihe River Basin in recent three decades are analyzed by the perspective of groundwater recharge and discharge system. The results indicate that with the different intensities of land use changes, the impacts on the groundwater recharge were 2.602×108 m3/a in the former 15 years (1969-1985) and 0.218×108 m3/a in the latter 15 years (1986-2000), and the impacts on the groundwater discharge were 2.035×108 m3/a and 4.91×108 m3/a respectively. When the groundwater exploitation was in a reasonable range less than 3.0×108 m3/a, the land use changes could control the changes of regional groundwater resources. Influenced by the land use changes and the large-scale exploitation in the recent decade, the groundwater resources present apparently regional differences in Zhangye region. Realizing the impact of land use changes on groundwater system and the characteristics of spatial-temporal variations of regional groundwater resources would be very important for reasonably utilizing and managing water and soil resources.     

Application of Time-Series Model to Predict Groundwater Dynamic in Sanjiang Plain,Northeast China

To study the groundwater dynamic in the typical region of Sanjiang Plain, long-term groundwater level observation data in the Honghe State Farm were collected and analyzed in this paper. The seasonal and long-term groundwater dynamic was explored. From 1996 to 2008, groundwater level kept declining due to intensive exploitation of groundwater resources for rice irrigation. A decline of nearly 5 m was found for almost all the monitoring wells. A time-series method was established to model the groundwater dynamic. Modeled results by time-series model showed that the groundwater level in this region would keep declining according to the current exploitation intensity. A total dropdown of 1.07 m would occur from 2009 to 2012. Time-series model can be used to model and forecast the groundwater dynamic with high accuracy. Measures including control on groundwater exploitation amount and application of water saving irrigation technique should be taken to prevent the continuing declining of groundwater in the Sanjiang Plain.     

地下水深埋区咸水灌溉对土壤盐渍化影响的初步研究——以民勤绿洲为例

 针对民勤绿洲近几十年来大量开采地下水造成地下水位急剧下降,同时大规模开采地下劣质咸水用于农业灌溉的现状,采用咸水沟灌大田试验,就绿洲地下水深埋区（＞5 m）咸水灌溉对土壤盐渍化的影响进行了研究。结果表明,在地下水深埋区,灌溉水带入的盐分是土壤表层盐分积累的主要来源;播种前大定额淡水灌溉,土壤明显脱盐,但随着生长季内咸水灌溉及灌溉定额的减少,土壤开始返盐,到生长季末,根区土壤显著积盐,2 g·L-1和5 g·L-1咸水灌溉下土壤的积盐率分别为22.67%和35.30%;高垄覆膜种植方式下,膜上沟灌对沟下土壤盐分淋洗明显,但是在行间非覆膜区盐分强烈聚集;咸水灌溉导致根区土壤pH值升高,碱化度增大,绿洲土壤存在着明显的碱化趋势。     

雷州半岛土壤渗透性及其与地下水补给关系

对雷州半岛土壤渗透性进行了分析,并结合地形地貌、降雨入渗补给情况,识别地下水潜在补给区。雷州半岛土壤渗透性空间差异较大,饱和渗透系数变化范围为 0.04~8.83 m/d。总体而言,半岛南部、遂溪西北部渗透性较好,中部较差。土壤渗透系数受到土地利用类型、土壤粒径、土壤有机质等的影响。随着土壤中值粒径和有机质含量的增加,土壤渗透系数增加。不同土地利用类型,其土壤平均渗透性优劣表现为：荒地＞桉树林＞甘蔗＞菜地＞菠萝＞其他林地＞香蕉＞苗圃＞坡稻＞水稻田。降雨入渗补给系数南北高、中间低,随着土壤渗透系数增加而提高。半岛南部石茆岭和石板岭一带,地势高,坡度较缓,同时土壤渗透性和降雨入渗补给系数相对较高,为雷州半岛地下水潜在补给区。     

塔里木河下游生态需水估算

量化生态需水是流域水权分配的重要依据。以塔里木河下游大西海子水库至尾闾台特玛湖段为研究区,借助湿周法计算了该段河道内最小生态需水量,并基于2009年和2010年河段地下水分布特征,计算沿线河道两岸各1 km范围地下水恢复至目标埋深(5～4 m)的地下水恢复量,采用潜水蒸发法和面积定额法估算了沿线天然植被生态需水量。结果表明：（1）塔里木河下游大西海子-台特玛湖河道内年最小生态需水量为1.455×108 m3;（2）以5年为恢复期限,确定该河段地下水埋深恢复至5～4 m的年恢复需水量为0.608×108～1.466×108 m3;（3）取潜水蒸发法和面积定额法计算结果均值,确定研究区天然植被生态需水量为1.042×108 m3;（4）综合考虑,塔里木河下游大西海子-台特玛湖年生态需水总量为3.105×108～3.963×108 m3。     

黑河下游额济纳绿洲生态需水关键期及需水量

黑河流域中生态最为脆弱、植被退化最为严重而对全流域生态治理目标的实现极为关键的地区在下游额济纳绿洲。黑河分水方案主要控制年总量,由来水过程确定分水时机,采用“全线闭口、集中下泄” 的分水方式,这容易导致分水与下游绿洲需水的时间错位。要实现黑河分水对下游天然绿洲的作用和意义,不仅要充分保证分水量,更要选择适宜的分水时间,如果分水错过了下游绿洲生态需水的关键期,将会直接影响绿洲植被的正常生长。要维持黑河下游额济纳绿洲健康、稳定和持续发展,确定生态需水的关键期是首当其冲的问题。本文通过对黑河下游额济纳绿洲地下水位时空动态变化过程、天然植被耗水过程和绿洲生态过程及水文过程的关系研究,确定了黑河下游额济纳绿洲生态需水的关键期。建议在生态关键期保障输送必需的水量,合理调节水库出水量与河道径流量,保障4月和8月关键期的需水量,其中4月至少要保证0.80亿m3的输水量,8月至少要保证1.08亿m3的输水量,确保下游绿洲植被的生理需水,同时考虑到前期缺水和随后的月份水量消耗,尽可能增加关键月的配水量。     

Water resources utilization and eco-environmental safety in Northwest China

Northwest China includes Xinjiang Ugyur Autonomous Region, Qinghai Province, Gansu Province, Ningxia Hui Autonomous Region and Shaanxi Province, covering 308×104 km2. It is located in the warm-temperate zone and the climate is arid or semi-arid. Precipitation is very scarce but evaporation is extremely high. The climate is dry, the water resources are deficient, the eco-environment is fragile, and the distribution of water resources is uneven. In this region, precipitation is the only input, and evaporation is the only output in the inland rivers, and precipitation, surface water and groundwater change with each other for many times, which benefits the storage and utilization of water resources. The average precipitation in this region is 232 mm, the total precipitation amount is 7003×108 m3/a, the surface water resources are 1891×108 m3/a, the total natural groundwater resources are 1150×108 m3/a, the total available water resources are 438×108 m3/a, and the total water resources are 1996×108 m3/a and per capita water resources are 2278 m3/a. The water resources of the whole area are 5.94×104 m3/(a.km2), being only one-fifth of the mean value in China. Now, the available water resources are 876×108 m3/a, among which groundwater is proximate 130×108 m3/a.     

巴丹吉林沙漠地下水流场的宏观特征

黑河流域下游盆地与周边地区的水力联系是当地生态建设的关键问题。巴丹吉林沙漠与黑河流域下游盆地存在长达180 km的交界线,由于水文地质调查程度低,其地下水的流场不清楚,黑河流域下游天然水均衡账本中存在不确定因素。针对这个问题,在已有水文地质调查基础上,开展了巴丹吉林沙漠区域尺度的水位调查和钻孔勘探,获得461个已知水位点和63个水位约束点,绘制出巴丹吉林沙漠浅层地下水一级近似等水位线图。结果表明:研究区地下水位具有东南高、西北低的特点,水力梯度0.6‰~4.0‰,沙漠东南部地区的湖泊对地下水流场具有扰动作用,但没有改变宏观的地下水流向;第四系松散砂层是巴丹吉林沙漠浅层地下水的主要含水层,根据现有钻孔和物探资料,第四系沉积物在沙漠腹地较厚、边缘较薄,覆盖厚度普遍超过100 m,联通了沙漠和黑河流域下游地区的地下水;巴丹吉林沙漠的地下水补给黑河下游的古日乃湖、额济纳旗平原和拐子湖地区,地下水侧向出境流量为(0.61~1.97)×10⁸ m³·a^-1,其中进入古日乃湖平原的流量达到(0.33~1.06)×10⁸ m³·a^-1。计算结果仍然受到一些不确定因素的影响。     

格尔木河流域地下水生态功能及经济损益阈值解析

在西北内陆河流域,地下水是维系人类生存、生态环境和社会经济发展的重要水源,但这些流域生态环境脆弱。为保护地下水资源和脆弱的生态环境,亟待开展地下水合理开发利用研究。本文在分析格尔木河流域水文地质条件、环境地质问题基础上,采用遥感解译、野外调查和地下水动态监测的方法,界定了地下水的生态功能及阈值,即维系植被生态地下水埋深为0.5~10 m、减轻盐渍化程度的地下水埋深应大于3 m、减轻城市内涝的地下库容应大于3.42×10⁸ m³、维系达布逊湖面积的入湖流量应大于2.82×108 m³·a^-1。基于格尔木河流域生态系统服务价值构成,得到减轻城市内涝及减缓盐渍化程度的环境正效益值分别为8 000×10⁴元·km^-2和163×104 元·km^-2;地下水不合理开发利用导致植被退化、河湖面积萎缩的环境负效益值分别为191元·km^-2和1 032元·km^-2。本文研究成果可为流域内地下水资源开发利用和生态环境保护科学依据,同时也可为西北其他内陆河流域地下水合理开发利用借鉴。     

塔里木河下游间歇性输水对土壤水化学的影响

根据塔里木河下游2000-2006 年11 次间歇性输水影响下沿输水河道两侧地下水埋深、地下水化学组分变化的资料, 结合有关输水的基本资料和土壤盐分含量变化的适时监测数据, 分析了地下水化学特征的变化及影响其变化的各相关因子,结果表明：地下水化学特征的变化呈现明显的阶段性规律, 地下水化学组分的变化与距离输水河道的远近、地下水埋深、河道径流量以及土壤盐分含量之间具有较高的相关性; 地下水埋深在5 m 及5 m 以下时, 地下水化学组分含量较低, 水质较好。而埋深在5 m 时的水位条件能够满足该区域建群种植物的生存, 为输水条件下的理想水位;地下水化学特征变化的阶段性特点和土壤剖面盐分含量的分布规律及其相互关系说明,在当前输水模式下配合面上输水将能更好地促进生态恢复。     

Ecological water demand of natural vegetation in the lower Tarim River

We have appraised the relationships between soil moisture, groundwater depth, and plant species diversity in the lower reaches of the Tarim River in western China, by analyzing field data from 25 monitoring wells across eight study sites and 25 permanent vegetation survey plots. It is noted that groundwater depth, soil moisture and plant species diversity are closely related. It has been proven that the critical phreatic water depth is five meters in the lower reaches of the Tarim River. We acquired the mean phreatic evaporation of different groundwater levels every month by averaging the two results of phreatic evaporation using the Qunk and Averyanov formulas. Based on different vegetation types and acreage with different groundwater depth, the total ecological water demand (EWD) of natural vegetation in 2005 was 2.4×108 m3 in the lower reaches of the Tarim River. Analyzing the monthly EWD, we found that the EWD in the growth season (from April to September) is 81% of the year’s total EWD. The EWD in May, June and July was 47% of the year’s total EWD, which indicates the best time for dispensing artificial water. This research aims at realizing the sustainable development of water resources and provides a scientific basis for water resource management and sound collocation of the Tarim River Basin.     

华北平原地下水动态变化

The groundwater level of 39 observation wells including 35 unconfined wells and 4 confined wells from 2004 to 2006 in North China Plain (NCP) was monitored using automatic groundwater monitoring data loggers KADEC-MIZU II of Japan. The automatic groundwater sensors were installed for the corporation project between China and Japan. Combined with the monitoring results from 2004 to 2006 with the major factors affecting the dynamic patterns of groundwater, such as topography and landform, depth of groundwater level, exploitation or discharge extent, rivers and lakes, the dynamic regions of NCP groundwater were gotten. According to the dynamic features of groundwater in NCP, six dynamic patterns of groundwater level were identified, including discharge pattern in the piedmont plain, lateral recharge-runoff-discharge pattern in the piedmont plain, recharge-discharge pattern in the central channel zone, precipitation infiltration-evaporation pattern in the shallow groundwater region of the central plain, lateral recharge-evaporation pattern in the recharge-affected area along the Yellow River and infiltration-discharge-evaporation pattern in the littoral plain. Based on this, the groundwater fluctuation features of various dynamic patterns were interpreted and the influencing factors of different dynamic patterns were compared. Foundation: National Natural Sciences Foundation of China, No.40671034; No.40830636 Author: Wang Shiqin (1981–), Ph.D., specialized in hydrology and water resources, water cycle of watershed.     

基于FEFLOW和GIS技术的矿区地下水动态模拟及预测

矿区地下水动态研究是山西亟待解决的重大需求问题。针对山西矿区水资源短缺与水环境恶化等现状,通过分析气象、水文、地质地貌、开采现状等监测数据资料,以FEFLOW模型和GIS技术为平台,构建山西矿区三维地下水数值模型,进行地下水动态研究,模拟并预测了4种不同情境下矿区地下水动态过程,从而定量分析采矿活动对地下水动态的影响,揭示矿区开采对地下水系统的作用机制。结果表明：当矿区开采强度提高10%、30%、50%时,地下水整体流场和运动趋势没有大的变化,但在矿区南部地下水流场发生突变,等值线形变,且在东南部形成一个水位变化剧烈的低水位带,迫使地下水流向发生偏转。水位分析表明采矿活动会造成地下水位整体下降,下降幅度与开采强度呈正相关关系。地下水系统均衡分析表明,当开采强度保持现状或提高10%,地下水系统仍然处于正均衡,补给量大于排泄量,当开采强度提高30%、50%时,系统转为负均衡状态,补给量小于排泄量,地下水水量大幅度减少。研究成果可为矿区制定合理的开采方案,保护矿区地下水资源提供参考依据,为有效遏制矿区水环境恶化、确保矿区水安全提供科技支撑。     

霍景涅里辛沙漠地下水化学和同位素特征

在综合分析地质条件基础上,运用水化学及同位素技术,并结合现场调查及室内分析的方法,对霍景涅里辛沙漠地下水进行研究,分析了研究区地下水化学及稳定同位素特征,讨论了地下水的矿化过程及影响因素,确定了沙漠区地下水的补给来源。结果表明：沙漠区潜水中各离子组分平均值均大于承压水,潜水的溶解性总固体（TDS）平均值远大于承压水,说明潜水的蒸发作用大于承压水;控制潜水中主要离子成分的作用主要为溶解作用、交替吸附作用以及蒸发作用,控制承压水中主要离子成分的作用主要为溶解作用;沙漠区潜水与承压水具有一定的水力联系;地下水的补给来源主要为山区冰雪融水及降水,潜水的补给高程为1 370m,承压水的补给高程为1 650m。     

塔里木河下游胡杨气体交换特性及其环境解释

结合塔里木河下游不同地下水埋深下胡杨的气体交换参数及其环境因子的实测结果,探讨地下水位及环境因子对胡杨光合速率(Pn)、蒸腾速率(Tr)、气孔导度(gs)、水分利用效率(WUE)等气体交换参数的影响规律。研究表明:随着地下水位下降,胡杨净光合速率和蒸腾速率日变化最大值提前,地下水埋深越深,净光合速率“双峰”曲线趋势越明显,地下水位4.37 m以上时,蒸腾速率呈“双峰”曲线,当地下水位下降到5.91 m时,蒸腾速率呈“单峰”曲线;低地下水埋深下,光合作用受抑制的主要原因是气孔限制;随着地下水位下降,光合抑制的主要原因则是非气孔限制;适度水分胁迫有利于提高胡杨水分利用效率\.同时,结果显示: 4 m为胡杨的合理生态水位,地下水位为4~5 m时,胡杨受到轻度水分胁迫,低于6 m,胡杨受水分胁迫加剧。     

塔里木河下游地下水化学特征对生态输水的响应

结合2000~2002年塔里木河下游5次生态输水过程,通过对沿河40眼地下水监测井采集的水化学资料的分析表明：塔里木河下游地下水化学特征随五次间歇性生态输水发生明显变化。地下水化学对输水的响应表现为初期、中期和后期三个阶段：初期,地下水化学成分中的主要离子含量和矿化度都明显上升;中期逐步下降;输水后期又逐步上升。通过对地下水盐运移机理以及生态输水后地下水化学变化特征的分析得出,单一河道输水方式不如双河道,甚至多河道输水更有利于生态的恢复,另外,生态输水只是对地下水中盐分浓度起到了稀释作用,只有采取一系列工程和管理措施才能使下游水质真正好转。     

土地利用对地下水位下降的影响--以河北平原为例

本文利用简化的水量平衡模型,模拟了河北平原1985-1995年多年平均降水入渗系数和含水层给水度,在此基础上计算出各用水部门和各种农作物平均每年引起的地下水位下降幅度。结果表明:农业用水是引起河北平原地下水位下降的主要因素,其次是工业用水和生活用水。小麦引起的地下水位下降幅度最大,谷子最小。生产单位产值的小麦消耗地下水量最大,引起的地下水位下降幅度也最大,生产单位产值的蔬菜消耗地下水量最小,引起的地下水位下降幅度也最小。实现河北平原地下水资源可持续利用,调整种植业结构当务之急。     

Dynamic evaluation of groundwater resources in Zhangye Basin

Groundwater resource is vital to the sustainable development of socio-economics in arid and semi-arid regions of Northwest China. An estimation of the groundwater resources variation in Zhangye Basin was made during 1985–2013 based on long-term groundwater observation data and geostatistical method. The results show that from 1985 to 2013, groundwater storage exhibited tremendous dissimilarity on temporal and spatial scale for the whole Zhangye Basin, especially before and after implementation of the water diversion policy. Trend of groundwater storage varied from quick to slow decline or increase. The accumulative groundwater storage decreased nearly 47.52×10~8 m~3, and annual average depletion rate reached 1.64×10~8 m~3/a. Among which, the accumulative groundwater storage of the river and well water mixed irrigation district decreased by 37.48×10~8 m~3, accounting for about 78.87% of the total groundwater depletion of the Zhangye Basin. Accumulative depletion of groundwater storage varied in respective irrigation districts. Though groundwater resources depletion rate slowed down from 2005, the overall storage in the whole basin and respective districts during 1985–2013 was still in a severe deficit such that, the groundwater resource was in a rather negative balance, which could threaten the local aquifer. This is the joint effect of climate change and human activities, however human activities, such as water diversion policy and groundwater exploitation, became increasingly intense. Our research results could provide a reasonable estimation for the groundwater balance in Zhangye Basin, providing a scientific basis for water resources unified planning and, this method can provide a relatively reliable way of estimation for large scale groundwater resources.