Depth Of Groundwater Level Research Articles

Gas exchange in sphagnum mosses at different near-surface groundwater levels

Studies performed in a southern taiga pine bog forest under different temperature and moisture conditions have shown that the dependence of sphagnum CO2 exchange on environmental factors is largely regulated by near-surface groundwater level (GWL). When the GWL is at a depth of 4–7 cm, CO2 uptake by sphagnum increases with rise in temperature; at a GWL depth of 21 cm, CO2 emission (instead of uptake) takes place, decreasing at higher temperatures. As the GWL descends and air temperature rises, CO2 becomes higher. At a GWL depth of more than 43 cm, the influence of temperature decreases and CO2 emission drops by more than half. The dependence of sphagnum CO2 exchange on solar radiation is also ambiguous. This dependence is logarithmic at a GWL depth of 4 to 21 cm, but at the latter level sphagnum mosses release CO2 rather than absorb it, with CO2 emission decreasing significantly at an irradiance of more than 200 W/m2. Sphagnum CO2 exchange at GWL below 30 cm is independent of solar irradiance, and further increase in GWL depth leads to reduction in CO2 emission.

Spatiotemporal Variability Analysis of Groundwater Level for Water Resources Development and Management in Northern Punjab, India

The present study was conducted for investigating spatiotemporal variations in the groundwater levels recorded on monthly basis during 2006-2013 in northern parts of Punjab, India, comprising of 3 districts viz., Amritsar, Gurdaspur and Tarn Taran. The entire data of 8 years was divided into three seasons: pre-monsoon (February-May), monsoon (June-September) and post monsoon (October-January). It was observed in Gurdaspur district that the groundwater level depths increased in monsoon seasons with an overall variation range of 0.22% to 9.67%. In Amritsar district, in monsoon season, the highest increase of 6.22% in groundwater level depth was found in the Ajanala block and least increase of 0.36% in Tarshika, while in Tarn Taran district, the highest increase of 3.87% in groundwater level depth was found in the Noushera Pannua block and least increase of 0.95% was found in Tarn Taran block. The groundwater level decreased in the range of 0.15 m to 1.80 m with an annual decrease in groundwater level in the range of 0.02 m to 0.23 m. The increase in groundwater level depth in monsoon seasons was found due to extreme usage in irrigation for rice crop and the recharging of aquifers is not speedy. However, it has also been observed that the groundwater level rises again in the post monsoon season due to the groundwater resilience of the aquifers. Besides this, the extensive recharge in the area is observed by Ravi and Beas rivers because of perennial nature. A regular monitoring of groundwater in different seasons of the year and its spatiotemporal analysis is required for adopting the appropriate management practices including conjunctive use of surface and groundwater for maintaining its sustainability.

Influence of Physicochemical Parameters on Burrowing Activities of the Fiddler Crab Uca tangeri at the Huelva Coast (Southwest Spain): Palaeoichnological Implications

Populations of fiddler crabs (Uca tangeri) occupy several marginal-marine environments of the Huelva coast of Southwest Spain. Associated with these organisms are large, open burrows that represent domiciles recognized by numerous circular apertures. Ichnological analysis reveals variations in features of the biogenic structures between and through different marginal-marine environments, including an intertidal sandy beach and a salt-marsh setting into an estuary zone. We hypothesized that the observed variations in burrows of Uca tangeri related to changes in particular physicochemical parameters in the overall habitat. Herein the possible relationship between the ichnological features of burrow crabs (density and diameter of aperture) and selected physicochemical factors (pH, temperature, sediment texture, grain size, firmness, and depth of ground water level) are treated. The obtained results in two selected areas where several transects were conducted suggest a variable relationship, with several parameters showing a weak influence on the burrowing behaviour (e.g., pH, and temperature), while others reveal a major important (e.g., firmness and depth of the ground water level). These results are relevant to palaeoichnological analyses regarding the behavior of trace fossil producers, the relationship between palaeoenvironmental limiting factors and burrow features, and to the improvement of characterizations regarding substrate-controlled ichnofacies.

Responses of groundwater vulnerability to artificial recharge under extreme weather conditions in Shijiazhuang City, China

Artificial recharge is becoming one of the most important ways to deal with water shortage and induced environmental geological problems, but it also brings potential groundwater contaminant risks, especially under extreme weather conditions. A classic method, DRASTIC, and groundwater flow simulation model have been used to analyze the response of groundwater vulnerability to artificial recharge under extreme weather conditions. The results show that a simultaneously abundant year and scarce year of the local area and the Han River Basin are 7.46 and 6.60%, respectively. The quantities of artificial recharge water would be 8.72 × 104m3/a and 4.64 × 104m3/a, respectively. Five scenarios with extreme weather conditions were discussed. The groundwater vulnerability would not change a great deal without extreme conditions under artificial recharge. Under extreme abundant conditions, the induced groundwater level lowering would making the depth of groundwater level increase, and the vulnerability would be lower. Under extreme abundant conditions, the decreased depth of groundwater level and increased net recharge made the vulnerability increase obviously, and the low vulnerability area was converted into the moderate and high vulnerability areas. More attention should be paid to the quality of recharged water and monitoring schemes should be carried out around the infiltration field.

Assessment of soil salinization based on a low-cost method and its influencing factors in a semi-arid agricultural area, northwest China

An investigation of soil salinization was carried out in the Nanshantaizi area (Northwest China) with WET Sensor. This device can measure such soil parameters as bulk soil electrical conductivity, water content, and the pore water electrical conductivity that are important for soil salinization assessments. A distribution map of soil salinization was produced, and the factors influencing soil salinization and its processes were discussed in detail. The study shows that moderately salinized to salt soils are mainly observed in the alluvial plain, where groundwater level is high and lateral recharge water contains high salinity. Nanshantaizi is covered by slightly salinized soils. The soil salinization distribution estimated by WET Sensor is generally consistent with the actual levels of salinization. Soil salinity in Nanshantaizi is mostly of natural origin and accumulated salts could leach to deeper soils or aquifers by water percolation during irrigation. Groundwater evaporation, groundwater level depth and quality of recharge water are important factors influencing soil salinization in the alluvial plain.

Winter Hydrology and NO3− Concentrations in a Forested Watershed: A Detailed Field Study in the Adirondack Mountains of New York1

Abstract: More than 85% of NO3− losses from watersheds in the northeastern United States are exported during winter months (October 1 to May 30). Interannual variability in NO3− loads to individual streams is closely related to interannual climatic variations, particularly during the winter. The objective of our study was to understand how climatic and hydrogeological factors influence NO3− dynamics in small watersheds during the winter. Physical parameters including snow depth, soil temperature, stream discharge, and water table elevation were monitored during the 2007‐2008 winter in two small catchments in the Adirondack Mountains, New York State. Snowpack persisted from mid‐December to mid‐April, insulating soils such that only two isolated instances of soil frost were observed during the study period. NO3− export during a mid‐winter rain‐on‐snowmelt event comprised between 8 and 16% of the total stream NO3− load for the four‐month winter study period. This can be compared with the NO3− exported during the final spring melt, which comprised between 38 and 45% of the total four‐month winter NO3− load. Our findings indicate that minor melt events were detectable with changes in soil temperature, streamflow, groundwater level, and snow depth. But, based on loading, these events were relatively minor contributors to winter NO3− loss. A warmer climate and fluctuating snowpack may result in more major mid‐winter melt events and greater NO3− export to surface waters.

Vegetation-Groundwater Relationship Model for Subei Lake Watershed and Prediction of Vegetation Succession Rules under Exploitation

Located in an arid and semi-arid region with low rainfall and high evaporation, the Subei Lake watershed has fragile ecological environment; the impact of groundwater level recession on vegetation ecology is the key problem for the exploitation and utilization of groundwater resource in this region. In this paper, a succession model for vegetation and burial depth of groundwater level was constructed through field survey, and was used along with numeric simulation to predict the change in burial depth of groundwater level in the study area under exploitation and to analyze and predict the vegetation succession rules and processes. It is believed from the study that, while groundwater level falls constantly, the burial depth of groundwater level will increase gradually, and succession will occur gradually from aquatic vegetation to mesophytic and xerophytic vegetations, from Carex L. and Iris ensata Thunb shoaly lands to Achnatherum splendens shoaly lands, from Salix psammophila shrubs to Artemisia desterorum Spreng shrubs, and from Populus simonii to Salix matsudana.

Depth of water uptake in woody plants relates to groundwater level and vegetation structure along a topographic gradient in a neotropical savanna

Vegetation structure of the savannas is variable across the landscape, ranging from open grassland to savanna woodland within topographic gradients of a few hundred meters in length. Here we investigated whether patterns of soil water extraction by the woody layer and vegetation structure changed in response to groundwater depth. We determined depth of plant water uptake, groundwater level and vegetation structure on five different locations along a topographic gradient in the highlands of Central Brazil. The elevation gradient of about 110 m covered all vegetation physiognomies generally associated with topographic gradients in savannas of Central Brazil. To estimate the depth of plant water uptake in the different slope positions we relied on comparisons of hydrogen and oxygen isotope ratios of plant stem water, water from different soil depths, from groundwater and from rainfall. We subsequently used a stable isotope mixing model to estimate vertical partitioning of soil water by woody plants along the elevation gradient. We were able to show that groundwater level affected plant water uptake patterns and soil water partitioning among savanna woody species. Vegetation at higher elevation extracted water from deeper unsaturated soils and had greater variability in water uptake strategies, which was coupled to a denser and more complex woody layer. Plants on these soils used stored water from both shallow (<0.6 m) and deep (0.6–2.00 m) soil layers. At lower elevation sites, however, the presence of a water table near the soil surface restricted water uptake to the shallower wet season unsaturated zone of the soil profile. The sparser woody vegetation is probably composed of species that only rely in superficial water uptake, or are plastic in relation to root characteristics.

EFFECT OF GROUNDWATER LEVEL DEPTH AND IRRIGATION AMOUNT ON WATER FLUXES AT THE GROUNDWATER TABLE AND WATER USE OF WHEAT

ABSTRACTThree irrigation water regimes (90.0, 67.5, and 45.0 mm) and five groundwater table depths (1.5, 2.0, 2.5, 3.0, and 3.5 m) were considered in a lysimeter experiment to investigate the effect of groundwater level and irrigation amount on water fluxes at the groundwater table and water use of wheat. Results show that deep percolation (irrigation of 16–23%) occurred to a considerable extent in the present irrigation level at a shallow groundwater table of 1.5–2.0 m. Capillary rise comprised 29% of the water use of wheat, within the period from regreening to harvest, at 1.5 m groundwater table depth, and was reduced with an increase in table depth. A relationship between groundwater contribution and groundwater table depth was also found. In the present irrigation conditions, the water productivity (WPb) of wheat was enhanced from 3.59 kg m‐3 at a shallower groundwater level depth of 1.5 m, to 4.58 kg m‐3 at a deeper groundwater level depth of 3.5 m. WPb can be higher if deficit irrigation is enforced and can reach 3.93–6.03 kg m‐3. Similarly, a relationship between WPb and groundwater table depth was found. Hence, the irrigation amount per time for local wheat can be reduced to 45.0–67.5 mm, depending on the groundwater level depth, in order to use water resources effectively. Copyright © 2011 John Wiley &amp; Sons, Ltd.

Ecological monitoring of wetlands in semi-arid region of Konya closed Basin, Turkey

Wetland ecosystems are of global significance having productive, regulatory and informative function. These wetlands are crucial for the long-term protection of water sources, as well as the survival of its unique biodiversity. Most of the wetlands of Turkey are now facing serious threat from the anthropogenic sources and now near to the verge of extinction. This study has been carried out to monitor vegetation dynamics and ecological status of wetlands of Koyna basin at spatial and temporal scale. This study has involved MODerate-resolution Imaging Spectroradiometer (MODIS) images of the year 2000, 2004 and 2008 on daily basis with spatial resolution of 1 km. The MODIS 16 days composite NDVI time series products of 250-m spatial resolution from year 2000 to 2008 has been utilized to monitor the ecological status of the wetlands. The European Nature Information System habitat classification map, meteorological data (precipitation, temperature) coupled with field data has been utilized to validate NDVI values of nine habitats in the wetlands. The time series analyses of NDVI data values have been correlated with the groundwater level depth from 1996 to 2004. The overall analysis has shown a declining trend of NDVI over the year 2000 to 2008, indicated a degraded wetland condition in span of 9 years.

Application of Visual MODFLOW to the Dynamic Change and Simulation of Deep Groundwater in Dezhou City, China

In view of this major environmental geology problem in Dezhou City that continuous overexploiting of deep groundwater has caused he rapidly-expansion of groundwater drop funnel in recent years, the dynamic change of deep groundwater in Dezhou City was systematically analyzed as well as the evolution and development of hydrodynamic field and deep drawdown cone in temporal and spatial variation was simulated by the application of the numerical Model. On the basis of hydrogeological conditions generalized in this region, Visual MODFLOW software was applied to build mathematical model of groundwater and stimulate the seepage field of groundwater. It predicted the expansion of groundwater drop funnel and the change of underground water level under the conditions of exploitation situation and different designed exploiting volume by the model built. The depth reduction and variation of groundwater under different design schemes for pumping rate were argued by contrast analysis of the calculated results. The forecasting result under the current situation of groundwater exploitation indicates that the drawdown of water level would increase more with the continuous exploitation when the exploiting volume of current situation is 2047×104m3/a. When (time)is equal to 5a(2013), (the decline depth of groundwater) is at 4.81～22.65m and the annual deceleration is at 0.96～4.53m/a. When is equal to 10a(2018), is at 14.32～32.87m as well as the annual deceleration is at 1.43～3.29m/a, and then the average elevation of central water level of funnel is -118.06m. The forecasting results under different design schemes for exploiting volume showed that the groundwater level would continuously decrease if the present exploiting quantity is still kept at 2047×104m3/a, which the depth of central groundwater level of funnel is 144.95m in 2012. While exploiting quantity cuts down to 1950×104m3/a, the groundwater level still constantly decreases, which the depth of central groundwater level of funnel is 133.90m in 2012. Only when exploiting quantity further cut down to 1750×104m3/a, the groundwater level would never descend after 2011, and then it would begin ascending, which the depth of central groundwater level of funnel would be 120.25m in 2012. According to the model stimulation of groundwater flow and the results of water balance analysis, the exploitation project was proposed that the drawdown cone would not further expand. The key measure to protect deep groundwater resources in this region is scientific planning of underground water, and ensuring that The allowable exploiting volume in this region should be kept at 1750×104m3/a in order that it can reach a benign circle with the balance of exploitation and supplementation.

Stability Analysis and Evaluation of Soil Cave Foundation under the role of Groundwater in Karst Area

Soil cave foundation is a common type in the soil foundation in karst area, the stability of the foundation will be directly affected by the soil cave collapse destruction. Currently, the stability evaluation of soil cave foundation is mostly focus on the quantitative evaluation, such as the collapse mechanism and prevention, while the qualitative assessment is rare. Based on the plastoelasticity theory, firstly analyze the stress state of the soil cave wall- surrounding body in the foundation, distinguish the stress concentration influence area, then improve the soil cave foundation stability computation model by using Mole- coulomb strength criterion, finally, take a soil cave foundation stability evaluation as the example in Tongren area, Guizhou, confirming the feasibility and reliability of the improvement model. The influence of the foundation bed size, buried depth, soil cave shape and groundwater level depth was further studied, which reveals the mechanism of the soil cave collapse destruction. And the research indicated that the improved model is feasible, when the foundation bed size is smaller, the buried depth is shallower, the hole shape is more spiky and the groundwater level depth is shallower, the soil cave stability coefficient will be bigger, which is more advantageous to the stability, and the influence of groundwater level depth is more sensitive to the soil cave stability, once the groundwater level depth dropped a little, the stable soil cave will become into failure and instability. Therefore, the quantitative evaluation should be paid more attention in soil cave foundation stability evaluation, particularly under the ground water environment, simultaneously, the calculation results, like soil cave foundation maximum size, the critical buried depth, the maximum water level buried depth, have the strong directive function to the soil cave foundation treatment and design.

Shallow groundwater dynamics in North China Plain

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.

GEOFÍSICA APLICADA A LA EVALUACIÓN DE LA VULNERABILIDAD A LA CONTAMINACIÓN EN ZONAS RURALES

Agricultural and cattle activities are considered to be the source of high risk of contamination of groundwater. The contamination is the result of the interaction between the contaminant charge and the aquifer vulnerability. The aim of this work was to evaluate the vulnerability of the Pampeano aquifer at some rural zones of the highly productive area of Pergamino-Arrecifes river basin. The traditional method of indexation was used taking into account the principal factors which influence: the depth of free groundwater level, the degree of confinement of the aquifer and the lithology of non saturated zone. The first one was obtained through geoelectrical prospecting, due to the lack of well information at some places. The last factors were estimated based on hidrogeological features known from some wells. The influence of the edaphic zone (soil) was incorporated as a new index by means of texture properties of soils sampled at each site and soil maps. Even if vulnerability was moderate for all the studied sites, some places along both margins of the Pergamino river had higher indexes than the surroundings of Arrecifes town. The small urban centers had greater risk of contamination of groundwater due to their intrinsic vulnerability (higher indexes) and the potential contaminant charge that intensive agricultural and cattle activities, which are developed around these sites, may generate. Higher values of nitrate concentrations were found at these places with a sharp increasing tendency during the last years, indicating the need of stronger control over the effect of these activities on groundwater contamination.&nbsp

Study on the groundwater exploitation test in the Yellow River lower reaches ??A case study on the north suburb waterworks of Zhengzhou, China

This paper presents the studies on groundwater resources potential of the Yellow River (YR) terrace in Zhengzhou area, China. The main aim of the research was to resolve water shortage problems induced by recent but frequent drying ups of the YR in its lower reaches. Geologic explorations and grouped-pumping tests were conducted in the area. Based on collected data a groundwater flow net was established. The buried depth of groundwater level and water bearing potential of the aquifers were evaluated. Conventional method was used to determine recharge of the groundwater by lateral infiltration of the YR in pumping patterns. The results show that the study region has a high water bearing potential and offers conditions for the construction of large water works. However, only limited recharge by lateral infiltration from the river is available when developing large scale groundwater exploitation in the riverside of the YR. Environmental impacts induced by embankment stability of the Great dyke of the YR could be minimized or eliminated by appropriate engineering methods.

An assessment of the risk associated with urban development in the Thiaroye area (Senegal)

Water quality data from 56 wells, aquifer characteristics, soil types and land use in the city suburb of Dakar were compared to assess the effects of land use on the Thiaroye groundwater quality. The study area encompassed an unsewered densely populated zone, agricultural land, low density villages, and undeveloped land located in the sand dunes. A method similar to GIS technologies was applied to evaluate the degree of vulnerability of the different parts of the aquifer in relation to urban development, land use and aquifer characteristics. The aquifer parameters (hydraulic conductivity, groundwater level depth, recharge, soil type) were re-evaluated qualitatively into three class rankings (high, moderate and low), depending on the likelihood for contaminants reaching the water table, then combined using the two matrix Boolean logic based approaches to identify the nine classes of vulnerability assessed in the aquifer domain. An attempt was made to explain the distribution of nitrate concentration with the assessed vulnerability. In the area assessed, in the densely populated zone running from Pikine, to Thiaroye and Yeumbeul, very high nitrate concentrations correspond with the highest vulnerability index (H1). Nitrate contamination in this area is a consequence of point-source seepage from individual septic systems improperly built in this area. In the eastern part of the aquifer, high nitrate concentrations at Deni B. Ndao, Mbawane and Golam localities coincide with a moderate vulnerability assessment. The major source of nitrate in these areas is induced by agricultural activities.

Soil frost effects on soil water and runoff dynamics along a boreal forest transect: 1. Field investigations

AbstractTo determine how soil frost changes flowpaths of runoff water along a hillslope, a transect consisting of four soil profiles directed towards a small stream in a mature forest stand was investigated at Svartberget, near Vindeln in northern Sweden. Soil temperature, unfrozen water content, groundwater level and snow depth were investigated along the transect, which started at the riparian peat, and extended 30 m upslope into mineral soils. The two, more organic‐rich profiles closest to the stream had higher water retention and wetter autumn conditions than the sandy mineral soils further upslope. The organic content of the soil influenced the variation in frost along the transect. The first winter (1995–96) had abnormally low snow precipitation, which gave a deep frost down to 40–80 cm, whereas the two following winters had frost depths of 5–20 cm. During winter 1995–96, the two organic profiles close to the stream had a shallower frost depth than the mineral soil profile higher upslope, but a considerably larger amount of frozen water. The fraction of water that did not freeze despite several minus degrees in the soil was 5–7 vol.% in the mineral soil and 10–15 vol.% in the organic soil. From the measurements there were no signs of perched water tables during any of the three snowmelt periods, which would have been strong evidence for changed water flowpaths due to soil frost. When shallow soil layers became saturated during snowmelt, especially in 1997 and 1998, it was because of rising groundwater levels. Several rain on frozen ground events during spring 1996 resulted in little runoff, since most of the rain either froze in the soil or filled up the soil water storage. Copyright © 2001 John Wiley &amp; Sons, Ltd.

Willow stand evapotranspiration simulated for Swedish soils

A soil model parameterized for an intensively managed willow stand on clay soil was applied to other willow stands on sandy, clay and organic soils in south-western Sweden. The model was site adapted regarding groundwater conditions and soil physical properties, such as the hydraulic conductivity and retention curve. To identify differences in evaporation properties between different stands, simulated and measured values of soil water tension at different depths were compared. At most sites, the simulated tension levels were higher than measured values. Modified simulations with site adapted parameters regarding root depth, leaf area index and the critical tension for water uptake lowered the tension levels to an acceptable degree. However, the modifications did not improve the dynamic behaviour for all sites. The level of agreement between simulated and measured tensions was largely determined by the assumptions concerning groundwater conditions. At some sites, the root depth and critical tension for water uptake were also important parameters. The main factor limiting evapotranspiration at the unirrigated sites was the availability of water which in turn was determined by groundwater level, soil properties and root depth. At the irrigated site, where soil water was not limiting, evaporation was only affected by a change in leaf area index. Evapotranspiration ranged from 365 mm to 495 mm for the period from May to October. Monthly crop coefficients showed similar seasonal patterns of change at the different sites with low values in May and maximum values at the end of the season. The increase in crop coefficients was attributed to the increase in leaf area. The high values at the late season were attributed to a low aerodynamic resistance.

Density of organic carbon in soil at coniferous forest sites in southern Finland

More detailed knowledge of the density of organic carbon in soils of boreal forests is needed for accurate estimates of the size of this C stock. We investigated the effect of vegetation type and associated site fertility on the C density at 30 mature coniferous forest sites in southern Finland and evaluated the importance of deep layers to the total C store in the soil by extending the sampling at eight of the sites to the depth of ground water level (2.4–4.6 m). The C density in the organic horizon plus 1 m thick mineral soil layer ranged from 4.0 kg/m2 to 11.9 kg/m2, and, on the average, increased towards the more productive vegetation types. Between the depth of 1 m and the ground water level the C density averaged 1.3–2.4 kg/m2 at the studied vegetation types and these layers represented 18–28% of the total stock of C in the soil. The results emphasize the importance of also considering these deep layers to correctly estimate the total amount of C in these soils. At the least fertile sites the soil contained about 30% more C than phytomass, whereas at the more fertile sites the amount of C in soil was about 10% less than the amount bound in vegetation.

Geophysical methods application in groundwater natural protection against pollution

Natural protection against groundwater pollution mostly depends on water-bearing bed coverage with permeable rocks presenting a good or bad pollution intrusion barrier between the surface and subterranean water. Additional positive effects of polluted groundwater self-purification in these zones are visible. Natural protection from surface pollutants primarily depends on natural (geological) factors: (1) presence of poorly permeable rocks; (2) depth, lithology (grain-size distribution), and filtration features of rocks covering groundwater reservoirs; and (3) aquifer depth. In contrast to artesian aquifers, quantitative and qualitative evaluation for natural protection of intergranular aquifers with a free water surface is significantly complicated. In this case, the estimation is possible with the help of a specially developed statistical method, which requires the following elements referring to the zone of aeration: (1) poorly permeable strata depth; (2) filtration features; (3) groundwater level depth; and (4) lithology. For quantitative evaluation, it is necessary to know the time interval for pollution propagating from surface of the terrain to the free water surface. Describe access is particularly useful in the domain of zones of sanitary protection defined around the source of groundwater. This exploration method could be considerably rationalized by geophysical methods application. Various methods are useful, namely: electric mapping and sounding, self-potential method, seismic reflection and refraction methods, gravity and geomagnetic methods, the “turam” method, and different well-logging measurements (gamma ray, gammagamma, radioactivity log, and thermal log). In the paper, geophysical methods applictations in natural protection against groundwater pollution and appropriate critical analysis are presented. The results of this paper are based on the experience and application of geophysical methods to groundwater studies in Yugoslavia by the author.