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1.
典型表层岩溶泉短时间尺度动态变化规律研究   总被引:24,自引:1,他引:23  
本文以广西马山县弄拉岩溶动力系统监测站为例,通过人工及自动记录,分别对表层岩溶泉水的物理化学特征变化进行了研究。短时间尺度监测表明,岩溶动力系统对环境变化十分敏感,响应及时。在不同的气候条件下,水的物理化学特征多日与昼夜动态变化有不同的表现。在正常气候(无雨)条件下,水温的变化与气温变化基本一致,pH与电导率之间具有较好的负相关关系,电导率峰值区滞后最高温度约4~5h。这可能与植被从光合作用向呼吸作用转变导致大气CO2浓度产生较大的梯度变化有关。而这种梯度十分有利于岩溶作用的进行。暴雨期间,稀释作用可贯穿整个降雨过程,但降雨1~2h后,表层岩溶带的高裂隙率和渗透性开始发挥作用,水动力作用和CO2效应逐渐占主导地位,而稀释作用对弱降雨过程仅作用于降雨的开始阶段。因此有必要把水、岩、CO2气体作为一个整体来解释表层岩溶作用的水文地球化学行为。  相似文献   

2.
利用多参数自动记录仪(CTDP300)对广西马山县弄拉监测站的降雨量及表层岩溶泉水的水位、水温、pH值、电导率进行了监测。结果表明,系统对环境变化响应及时。其地球化学行为表现为明显的季节与昼夜动态变化,且在不同的气候条件下,水化学动态变化有不同的表现。在正常气候(无雨)条件下,水温、pH与电导率之间具有较好的正相关关系。暴雨期间,降雨开始阶段稀释作用明显。降雨中后期,CO2效应逐渐占主导地位。因此有必要把水、岩、CO2气体作为一个整体来解释表层岩溶作用的水文地球化学行为。  相似文献   

3.
利用CTDP300多参数自动记录仪对重庆金佛山国家级自然保护区碧潭泉和水房泉的降雨量、水位、水温、pH值、电导率进行了监测。结果表明,不同海拔高度的表层岩溶泉水化学对环境变化十分敏感,且具不同的表现形式,气温和土壤CO2浓度是引起水化学动态变化的两个重要因子。位于海拔较低的碧潭泉气温,土壤CO2浓度相对较高,岩溶作用也相对强,位于海拔较高的水房泉则相对较弱。受气温控制,前者的水温、pH表现出明显的白天高,夜间低的昼夜变化规律。降雨过程中,至少有两种效应在影响水化学性质:雨水的稀释效应和CO2效应,前者对碧潭泉水化学变化影响较大,降雨可引起泉水电导率、水温及pH的显著下降,降雨强度越大,下降速度与幅度越大,而从泉水电导率下降、pH值略有上升看,两者均对水房泉的水化学变化产生了影响。  相似文献   

4.
典型表层岩溶泉水短时间尺度动态变化规律   总被引:11,自引:0,他引:11       下载免费PDF全文
通过多功能自动化监测记录仪CTDP300,对金佛山表层岩溶泉碧潭泉物理化学性质的昼夜变化过程进行了研究.短时间尺度监测表明,岩溶动力系统对环境变化比较敏感,响应及时,水的物理化学性质昼夜动态变化在不同气候条件下有不同表现.在无雨条件下,水温的变化与气温基本一致,电导率峰值区滞后温度数小时,这可能与植被从光合作用向呼吸作用转变导致大气CO2浓度产生较大的梯度变化有关,而这种梯度十分有利于岩溶作用的进行,但由于植被覆盖和地质构造等因素的差异,滞后时间有较大不同;在暴雨期间,虽有植被和土壤的阻挡和调蓄作用,降雨对碧潭泉岩溶水还是有较强的稀释作用,但开始降雨后数小时左右,表层岩溶带高裂隙率和渗透性开始发挥作用,水动力作用和CO2效应逐渐占主导地位.  相似文献   

5.
常见的碳酸盐岩主要有灰岩和白云岩,两者的岩溶作用机理不同,因而常形成不同的地貌格局。在我国西南地区,若在小范围内有灰岩和白云岩出露时,往往在山体陡峭的部位出露质纯层厚的灰岩,而山间平原多出露白云岩。这种地层组合结构致使表层岩溶带的发育具有独特的双重岩性结构。基于兰电堂表层岩溶系统的研究,发现绝大部分水样的水化学类型均为HCO3-Ca·Mg型,其主要阳离子Ca2+和Mg2+质量浓度的季节动态变化趋势不明显,但对短期降水稀释效应及森林植被CO2效应的响应则非常迅速。将降水量小且比较均匀的8、9、10及12月水样的ρ(Ca2+)和ρ(Mg2+)关系曲线定义为"同比例溶解线",并用其判别不同降水条件下泉水化学成分差异的成因。另外,为了研究次生森林生态功能逐步恢复条件下岩溶作用强度的变化趋势,对近10年来弄拉表层岩溶泉水化学组分进行分析对比,发现岩溶水化学中主要阴、阳离子浓度均有增加趋势,也进一步佐证了森林植被的岩溶效应。  相似文献   

6.
亚热带森林岩溶区土壤CO2迁移动态初步研究   总被引:6,自引:0,他引:6  
贵州茂兰是研究森林覆盖下岩溶表层系统结构特征、运行规律的重要基地.本文初步研究了该地区碳迁移的若干特征 (1) 土壤剖面中CO2浓度变化.秋、冬季土下CO2浓度,50cm处始终高于20 cm处,而在春、夏季土壤剖面中CO2浓度变化幅度大,20cm处的浓度时常高出50cm处. 土下20cm、50cm处CO2浓度在不同季节的变化趋势是夏季(32 833×10-6、 38 666×1 0-6)春季(24 416×10-6,28 800×10-6)秋季(6 450×1 0-6),14 216×10-6>冬季(3 833×10-6,8 833× -6),土下CO2浓度变化趋势与温度和降雨量有较好的正相关关系.20cm处的CO 2浓度变化与温度的相关系数r=0.89,与降雨量的相关系数r=0.70;50cm处的CO 2浓度变化与温度的相关系数r=0.69, 与降雨量的相关系数r=0.66.(2)土壤呼吸释放C O2的速率有类似的变化规律夏季为339.68mg.m-2.h-1、为281. 74mg.m-2.h-1、秋季为206.59mg.m-2.h-1、冬季为65.53mg.m-2.h-1.年均排放量为1.96kg.m-2.yr- 1.(3)随水排泄HCO3-1是岩溶表层泉碳迁移的重要组分.表层泉水的H CO3-1浓度的季节变化与气温、月降雨量、土下20cm处CO2浓度存在着负相关,其相关系数r=-0.57、-0.71和-0.47,而与表层泉水的pH值之间没有显著的相关关系.这与非森林岩溶区的观测结果有一定的差异,内在的机理需要对相关的生物学的指标进一步的研究;(4)野外溶蚀试片的测试结果表明,夏季的岩溶作用强度是春季的2.6倍.  相似文献   

7.
吴孔运  姜光辉  刘玉 《地下水》2005,27(3):175-178
金佛山岩溶泉水化学呈现日变化和空间变化的动态特征.在时间上,碧潭泉水化学特征呈现周期性的日变化规律,而水房泉日变化规律不甚明显.由于海拨高程的影响,金佛山岩溶泉水化学变化动态对降雨直接响应的效应不同:在同一时间里,碧潭泉对降水的响应微弱;而水房泉水中的Ca 、Mg2 和HCO3-等离子浓度随降雨而上升,它主要受碳酸盐岩-水-CO2相互作用中的CO2的控制.金佛山岩溶泉水化学特征还受岩性的控制.  相似文献   

8.
以重庆青木关岩溶槽谷姜家泉野外观测试验基地为例,利用CTDP300多参数水质自动记录仪、NITRATAX plussc在线硝氮分析仪及HOBO小型气象站,分别对岩溶泉在不同降雨条件下水化学的动态变化特征进行了监测研究。结果表明:岩溶泉水pH值受偏酸性雨水的影响而降低;水温变化取决于降雨量、持续时间及气温等因素影响。分析认为,电导率的变化随环境的不同而不同,一般降雨环境下雨水的稀释作用仅表现在降雨的开始阶段,之后裂隙含水介质起主要作用;暴雨环境下雨水的稀释作用贯穿整个降雨过程,地下河水质主要受岩溶管道裂隙控制,水动力作用占主要地位。NO3-含量与电导率变化呈正相关,都与降雨量密切相关,从而说明降雨是导致岩溶区土壤元素流失的主要原因,也是造成岩溶山区地下水污染的重要原因。岩溶泉水化学动态变化的监测研究对于解决岩溶石山区居民的饮水、水土保持及石漠化治理具有重要意义。  相似文献   

9.
降水对广西马山兰电堂泉水化学动态变化观测研究   总被引:5,自引:0,他引:5       下载免费PDF全文
利用多参数自动记录仪(CDTP300)对广西马山兰电堂泉的降雨量、水位、水温、pH值和电导率进行自动化监测,数据采集间隔为15 min。结果发现,降雨期间泉水pH值和温度呈升高趋势的同时却出现电导率急剧降低的现象。通过进一步利用WATSPAC软件计算泉水方解石饱和指数(SIC)、白云石饱和指数(SID)和二氧化碳分压(LogP-CO2),发现其SIC、SID和LogPCO2值在降雨期间均呈明显降低趋势。由此可以推断,兰电堂泉水化学动态变化是由雨水的稀释作用造成的,因为研究区具有较高pH值和低电导率的雨水能够形成坡面流快速通过岩溶管道系统影响泉水的水化学性质,并使稀释作用成为控制表层岩溶泉在雨季水化学动态变化的主要因素。  相似文献   

10.
岩溶区碳循环与大气CO2的源汇关系:以贵州岩溶区为例   总被引:1,自引:0,他引:1  
李彬  袁道先 《中国岩溶》1996,15(1):41-49
全球碳循环的研究表明,人为CO2收支存在不平衡现象,据不同的估算,其未知汇为(1.8±1.4)×10^15gC/a或(2.0~4.7)×10^15gC/a。通过对贵州高原岩溶区岩溶作用带及其相邻圈层碳循环的观测,研究表明,岩溶作用带的碳循环强度与其相邻圈层(土壤层,生物圈,大气圈)的碳循环强度密切相关,表层带岩溶泉水中的HCO^-3与上部圈层的CO2浓度呈较好的正相关关系。同时,在不同生态,地质条  相似文献   

11.
Ombla Spring is located on the Adriatic coast near the town of Dubrovnik. The spring discharges at sea level. To eliminate the influence of the tide, a small dam was constructed 50 m downstream of the spring outlet. The spring water overflows the dam crest at an elevation of 2.40 m. Since 1897 the springwater has been used for the water supply for Dubrovnik.  相似文献   

12.
13.
Hydrogeologic assessment—Figeh Spring,Damascus, Syria   总被引:2,自引:0,他引:2  
Hydrogeological studies at Figeh Springs were directed to determine groundwater flow paths, research, storage and discharge units, and the maximum reliable yield. The project was designed to provide information upon which to base pumpage to augment low-season flows from the spring which is the major water supply for the city of Damascus, Syria.As a basis for conclusions and recommendations, work included extensive surface geologic mapping, air photographic interpretation, a detailed well and spring inventory, and a quality of water sampling program. Geologic structural work included mapping and jointing, faulting, and folding, and an analysis of their impact on groundwater movement.  相似文献   

14.
四川牟尼沟珍珠泉和翡翠泉的同位素组成及氘过量参数研究   总被引:12,自引:1,他引:12  
本文基于四川牟尼沟珍珠泉和翡翠泉水的氢、氧同位素组成、氘过量参数及氚含量资料 ,详细分析和讨论了两泉地下含水层水的补给源、补给高度、水的运移途径和滞留时间及它们之间的水力联系。  相似文献   

15.
The relatively slow flow and exchange of Carr Inlet water with the main basin of Puget Sound, Washington, favor eutrophication. To study Carr Inlet’s circulation, the Model-measurement Integration Experiment in Estuary Dynamics (MIXED) was conducted in March–May 2003, spanning the spring bloom. From observations and numerical simulations the circulation was decomposed into tidal and subtidal components; the former was dominated by the M2 tide, the latter by atmospheric forcing. Near the surface, the subtidal velocity was correlated with wind. At mid depths, the subtidal velocity was organized into vertical bands arising from internal waves excited by wind forcing of the water surface. The tidal flow was more strongly steered by local bathymetry and weaker in peak magnitudes than the subtidal flow, yet it contributed more mechanical energy to the inlet. Tidal eddies reduce exchange of water through the inlet’s entrances. Numerical simulations with the Princeton Ocean Model recreated many observed features, including the three-layer vertical structure of outflow at the surface and bottom and inflow at mid depth, the mid-depth subtidal response to the wind, and characteristics of the tide. While the model produced greater subtidal flow magnitudes at depth and differences in the phase of the M2 tide compared to observations, overall the case study provided support for more comprehensive simulations of Puget Sound in the future.  相似文献   

16.
经野外取样和XRD测试技术,根据温泉沉积物的矿物学标识,将即墨Cl-Na型温泉沉积物划分为喷流相、越流相沉积和喷口-通道亚相沉积,并阐述其基本概念、成因以及"盆下源"沉积模式;建立起蛋白石-石膏-岩盐-锌铅铁矾-赤铁矿喷流沉积相和通道-喷口沉积亚相的矿物学标识.上述研究有以下几方面意义:①界定温泉沉积物的概念和划分成因类型;②建立盲温泉与古地热活动寻找标识,圈定地热中心,指导现代温泉地热资源开发;③提供现代海底热水沉积作用、成矿作用的模拟环境.  相似文献   

17.
陕西韩城清水温泉井是在水文观测孔基础上改造而成,使用1年后因止水不严导致冷水浸入而水温降低。依次采用了2种方法进行封堵止水,胶带止水法失败,水泥封堵止水法成功,积累了一定经验。  相似文献   

18.
Field data from 25 karst springs were collected during the summer of 2008 near Verrettes, Haiti, to gain a better understanding of water quality in fresh water springs used as the primary source of potable water in rural Haiti. Two water samples were taken at each spring for bacterial analysis: one sample was submitted to a local hospital for analysis, while a duplicate sample was cultured using inexpensive and commercially available Coliscan® Easygel® Kits. Both capped and uncapped springs were sampled in order to evaluate whether capping improves water quality. Water quality parameters and flow volume estimates were recorded at each spring; however, no correlations between field water parameters and the presence of E. coli or total coliform bacteria were found. Spring flow rates varied from 0.4 to 268.5 L/min. Geologic contacts and regional structures trend in a northwest direction and appear to be exerting a primary control on spring locations. E. coli and total coliform colony counts from the local hospital and Coliscan® Easygel® Kits yielded different results for the same springs due to sample handling and analysis complications common in rural Haiti. Water sample analysis and storage problems encountered during this study likely resulted in underprediction, rather than overprediction, of bacterial contamination. Water from 71 to 100% of the springs was unsafe to drink based on the World Health Organization (WHO) drinking water standard. Both capped and uncapped springs had bacterial counts in excess of the WHO standard, suggesting that water treatment from all sources is necessary to ensure clean and safe drinking water. Negatively impacted subterranean microbial ecosystems, poor sanitation practices, shallow karst aquifers with open flow paths, and high spring water temperatures, averaging 26.5°C, may be contributing to the observed bacterial abundance.  相似文献   

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20.
Ancient microbialites reflect interactions between microbial communities and environmental conditions. However, evaluating the relative roles of microbial community processes and environmental influences on microbialite morphology and internal fabric in the rock record can be challenging. The Neoproterozoic Beck Spring Dolomite preserves diverse microbialites, and thus provides an opportunity to explore the factors that influenced microbialite development locally. Stromatolitic, thrombolitic and composite microbialites are abundant in subtidal to upper intertidal carbonates in the Beck Spring Dolomite. Thrombolitic and composite microbialites have not been recognized previously in this unit, but compose much of the newly defined thrombolitic member. Stratigraphic relationships demonstrate that these three types of microbialites formed in close spatial and temporal association in subtidal to intertidal environments. The relative proportions and distributions of stromatolitic and thrombolitic microbialites vary with depositional environment; stromatolitic microbialites dominate in deeper intertidal to subtidal facies, whereas thrombolitic textures are more abundant in upper intertidal facies. Composite microbialites, composed of intermingled clotted and laminated textures, formed in all environments but are most abundant in intertidal facies. The broad environmental distribution of stromatolitic, thrombolitic and composite microbialites and the intermingling of textures suggest that laminated and clotted textures reflect diverse microbial community morphologies rather than environmental variations. Furthermore, the ca 750 Ma age of thrombolitic microbialites in the Beck Spring Dolomite requires that they formed without the influence of calcimicrobes or metazoans colonizing and grazing the microbial mat surface. Thus, these thrombolites provide further evidence that the biostratigraphic distribution of thrombolites cannot be uniquely attributed to evolution of calcifying and grazing organisms in the earliest Cambrian, and that older microbial communities were capable of producing clotted textures.  相似文献   

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