Denitrification in the recharge area and discharge area of a transient agricultural nitrate plume in a glacial outwash sand aquifer, Minnesota

2002 ◽  
Vol 38 (7) ◽  
pp. 10-1-10-26 ◽  
Author(s):  
J. K. Böhlke ◽  
R. Wanty ◽  
M. Tuttle ◽  
G. Delin ◽  
M. Landon
Keyword(s):  
Recharge Area ◽  
Discharge Area ◽  
Sand Aquifer ◽  
Glacial Outwash

THE ORIGIN OF HYDROCHEMICAL PATTERNS IN HUMMOCKY MORAINE

1967 ◽  
Vol 4 (6) ◽  
pp. 1065-1092 ◽  
Author(s):  
A. Rozkowski
Keyword(s):  
Groundwater Flow ◽  
Flow Model ◽  
Chemical Analyses ◽  
Soluble Salts ◽  
Recharge Area ◽  
Discharge Area ◽  
Transmission Zone ◽  
Significant Enrichment ◽  
Poorly Soluble ◽  
Shallow Zone

Hydrochemical investigations were carried out in a small local basin in hummocky moraine of southern Saskatchewan. The 'basin' consisted of a hill and surrounding permanent sloughs. The constructed Teledeltos flow model shows the typical pattern of groundwater flow near permanent lakes, where the hills are areas of recharge and the sloughs areas of discharge. Based on the chemical analyses of soil and till extracts as well as on the chemical analyses of slough and groundwater, the development of certain hydrochemical patterns in hummocky moraine can be explained.Three hydrochemical zones can be distinguished: SO4–Ca–Mg in the recharge area, SO4–Mg–Ca in the transmission zone, and SO4–Mg–(Na) in the discharge area. The increase of groundwater salinity from the recharge area to the discharge area is due to evapotranspiration as well as to the poor permeability of the glacial deposits.The SO4–Mg–Ca type of water of the recharge area is already formed in the zone of aeration. The subsequent changes of groundwater chemistry in the zone of saturation are induced by the enrichment of easily soluble salts and by the steady precipitation of poorly soluble salts. The sharp increase in salinity and the significant enrichment of the SO4–Mg type of water by easily soluble salts take place in the shallow zone of the discharge area close to the surface. The study of water extracts suggests the presence of groundwater discharge in the region of the capillary fringe of the recharge area also.The delivery of ions to the sloughs takes place by groundwater flow and inter-flow; therefore, the hydrochemistry of sloughs is primarily determined by the chemistry of these waters. The further metamorphosis of slough water is produced mainly by intensive evaporation as well as by ion exchange within the slough.

Influence of the location of production wells in unconfined groundwater basins: an analysis by numerical simulation

1990 ◽  
Vol 27 (5) ◽  
pp. 657-668 ◽  
Author(s):  
Duke Ophori ◽  
József Tóth
Keyword(s):  
Numerical Simulation ◽  
Steady State ◽  
Groundwater Resources ◽  
The Other ◽  
Recharge Area ◽  
Development Potential ◽  
Discharge Area ◽  
Other Hand ◽  
Well Yield ◽  
Production Wells

Development potential of groundwater resources under continuous production is calculated by numerical simulation for models of unit basins for the plains regions of Alberta, Canada, in order to analyze the relations between the location of water wells on the one hand, and well yield and basin stability, on the other. These relations are expressed in terms of two basin hydrologic parameters, namely the transitional basin yield (TBY) and the sustainable basin yield (SBY). TBY is the net cumulative inflow of water into the system, induced by and during development at a particular site, from an initial to a final steady-state condition. SBY, on the other hand, is the amount of water captured from precipitation due to production at a particular site under the newly established steady-state conditions. TBY is highest for well locations in the discharge area and decreases gradually as the sites are moved toward the recharge area. This is so because more of the naturally discharging, and thus otherwise lost, water is captured by wells located in discharge areas than by wells in recharge areas. On the other hand, SBY is greater if the wells are located in recharge areas than if they are in the discharge areas because an increasing percentage of precipitation is converted to infiltration by production wells as their locations are moved upslope in the basin. From a regional hydrological viewpoint, these are key relations in optimizing the development potential of the groundwater resources in extensive unconfined basins. Precipitation rate, simulated as maximum potential infiltration rate, is assumed to be constant over time. It is shown also that under conditions of restricted rainfall, a recharge-area development results in unstable basin-hydrological conditions sooner than when development takes place in the discharge area. Regional groundwater exploitation should, therefore, be initiated in discharge areas and moved towards recharge regions gradually, and only for compelling reasons. Factors such as precipitation rates and positions of aquifers within a basin affect TBY and SBY to various degrees, thereby influencing the optimal location of well sites in the basin.

On the Generation of Stream Runoff in Till Soils

1989 ◽  
Vol 20 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Allan Rodhe
Keyword(s):  
Hydraulic Conductivity ◽  
Overland Flow ◽  
Ground Surface ◽  
Areal Extent ◽  
Capillary Fringe ◽  
Recharge Area ◽  
Discharge Area ◽  
Total Head ◽  
Isotope Studies ◽  
Groundwater Outflow

Isotope studies in Swedish till basins indicate that stream stormflow is normally dominated by pre-event water. The rapid response of the groundwater outflow to infiltration may be explained by a large increase in the hydraulic conductivity of the soil towards the ground surface. In homogeneous soils the effect of the capillary fringe may be important in building up large total head gradients towards the stream. In generating runoff peaks in the streams, the saturated discharge area contributes 100 %, by saturation overland flow. Various parts of the recharge area contribute less than 100 %, and less effectively the longer the distance to the recharge area is. The areal extent of the contributing recharge area is considerably larger than the discharge area.

scholarly journals Groundwater Quality Distribution in Development City between Surakarta-Kartasura (Ground Water Hidrologi System Contemplation in Bengawan Solo Recharge)

2016 ◽  
Vol 15 (1) ◽  
pp. 90
Author(s):  
Alif Noor Anna
Keyword(s):  
Groundwater Quality ◽  
Trend Analysis ◽  
Population Data ◽  
Analysis Model ◽  
Recharge Area ◽  
Discharge Area ◽  
Positive Correlation ◽  
Comparative Model ◽  
Variant Analysis ◽  
Density Population

This research is conducted in Kartasura-Surakarta s area especially from an area that relatively does not grow (recharge area) to an area growing to became a city (discharge area). The area is phisiographically restricted by a groundwater contour (i.e. 200 m from sea level) and by three rivers (i.e. Pepe, Wiro, and Bengawan Solo). This research has one objective to know the distribution of groundwater quality in Kartasura-Surakarta that is located between Pepe river and Wiro river. This research uses survey model and description comparative model completed by cheking the field. On the one hand, survey model measures physical data and density population data, and on the other hand, description comparative model is used to know the influence of physical factors and density population factors on groundwater quality. Physical data and density population data collected by using purposive proportional random sampling are analyzed with trend analysis model, statistical analysis model (i.e. parsiil correlation and one-way variant analysis). The result of this research shows that the groundwater quality in the field declines. The trend analysis proves that most of the parameter concentrations of groundwater quality increase from the recharge area to the discharge area. Furthermore, the conclusion is also supported by the result of parsiil correlation analysis that shows a positive correlation between the distance and the most of the parameters, although the positive correlation between the depth of groundwater and the parameters of groundwater quality is weak. Moreover, the results of one-way variant analysis to the selected factors (i.e. geology formation, density groundwater contour, and density population) with the parameters of water quality show that there is a strong difference on the most of the parameters.

scholarly journals The Effects of Frozen Soils on Groundwater Recharge and Discharge in Granitic Rock Terrane of the Canadian Shield

1998 ◽  
Vol 29 (4-5) ◽  
pp. 371-384 ◽  
Author(s):  
G. A. Thorne ◽  
J. Laporte ◽  
D. Clarke
Keyword(s):  
Groundwater Flow ◽  
Flow System ◽  
Canadian Shield ◽  
Hydraulic Pressure ◽  
Recharge Area ◽  
Frozen Soils ◽  
Near Surface ◽  
Groundwater Flow System ◽  
Discharge Area ◽  
Soil Temperatures

Hydrologic measurements on groundwater flow systems of the Canadian Shield during the winter period provide insight into groundwater dynamics and can support conclusions based on measurements of the more “active” spring-to-fall, open-water period. To illustrate this, we present the results of detailed and continuous year-round measurements of parameters such as groundwater levels, air/soil temperatures, soil heat flux and soil moisture content which were made in upland recharge and wetland discharge areas of a local groundwater flow system in granitic terrane of the Canadian Shield. Recharge to the groundwater flow system in the rocks of the study area occurs as rain or snowmelt waters infiltrate exposed vertical and/or sub-horizontal soil-infilled fractures in outcrops of the upland area. During winter, soils in the fractures of the recharge area do not normally freeze below 0.5 m depth and shallow (5-20 cm depth) soil temperatures are most often only 1-2°C below freezing. During the spring melt period the temperature of these frozen soils remains near 0°C for several weeks as the pore ice absorbs thermal energy necessary for the phase transition from ice to water. However, despite these soils being completely or partially frozen, infiltration and recharge to the groundwater flow system in the rock occurs as shown by large and rapid rises in watertable and piezometric levels. In the groundwater discharge area of this flow system, near-surface soil temperatures (5 cm depth) reached minimums of about -12°C during the 1996 winter and freezing soils extended downward to more than 75 cm depth. During the spring melt period, as meltwaters add heat to the substrate, these shallow soil temperatures also, rise to near 0°C and remain frozen for several weeks as latent heat of fusion of ice becomes a factor. However, during the spring melt period, while ice covers ithe surface and soils are still frozen in the discharge area, groundwater level rises are recorded in both the overburden and bedrock of the discharge area. This is attributed to hydraulic pressure being rapidly transmitted to the discharge area through the low storativity groundwater flow system in the rock from the large waterlevel increases occurring in the rock of the adjacent upland recharge area.

scholarly journals Experimental Study on the Lateral Seepage Characteristics in the Tension Saturated Zone

2021 ◽  
Vol 18 (10) ◽  
pp. 5098
Author(s):  
Yongfeng Gong ◽  
Zuo Liu ◽  
Chuanming Ma ◽  
Minghong Li ◽  
Xu Guo
Keyword(s):  
Potential Gradient ◽  
Horizontal Flow ◽  
Saturated Zone ◽  
Total Water ◽  
Seepage Velocity ◽  
Seepage Field ◽  
Recharge Area ◽  
Flow Area ◽  
Discharge Area ◽  
Water Potential Gradient

To study the lateral seepage field in the tension saturated zone (TSZ), an experiment with no evaporation and precipitation infiltration was carried out in a self-made seepage tank filled up with fine sand. Based on the data and plots obtained, the lateral seepage field distribution features in the TSZ can be divided into three area for discussion: ascending area, descending area, and the nearly horizontal flow area. In the ascending and descending area, the total water potential gradient diminished from the recharge area to the discharge area and the seepage velocity was faster. In the nearly horizontal flow area, the total water potential gradient was lower and the seepage velocity was slower. The pressure potential gradually decreased horizontally from the recharge area to the discharge area, while in the vertical profile, it gradually decreased from the bottom to the top in the whole seepage area. In the absence of evaporation, the vertical water exchange among the saturated zone, TSZ, and unsaturated zone in nearly horizontal flow area is weak. Contrarily, in the ascending area and descending area, vertical water flows through both the phreatic surface and the upper interface of the TSZ. When there is lateral seepage in the TSZ, the thickness of the TSZ generally increases from the ascending area to the nearly horizontal area and then to the descending area. It should be pointed out that in the nearly horizontal area, the TSZ thickness is approximately equal to the height of the water column. Overall, the lateral seepage in the TSZ can be regarded as a stable siphon process, hence the siphon tube model can be further used to depict this lateral seepage.

PEMANFAATAN GLISERIN DARI RESIDU GLISERIN SEBAGAI PLASTICIZER UNTUK PEMBUATAN BIOPLASTIK DENGAN BAHAN BAKU PATI BONGGOL PISANG KEPOK

2017 ◽  
Vol 5 (4) ◽  
pp. 26-32 ◽  
Author(s):  
Azaria Robiana ◽  
M. Yashin Nahar ◽  
Hamidah Harahap
Keyword(s):  
Tensile Strength ◽  
Hydrogen Bonding ◽  
Fatty Acid ◽  
Maximum Yield ◽  
Sem Analysis ◽  
Water Molecules ◽  
Banana Weevil ◽  
Gelatinization Temperature ◽  
Recharge Area ◽  
Maximum Quantity

Glycerin residue is waste oleochemical industry that still contain glycerin. To produce quality and maximum quantity of glycerin, then research the effect of pH acidification using phosphoric acid. Glycerin analysis includes the analysis of pH, Fatty Acid and Ester (FAE), and analysis of the levels of glycerin. The maximum yield obtained at pH acidification 2 is grading 91,60% glycerin and Fatty Acid and Ester (FAE) 3,63 meq/100 g. Glycerin obtained is used as a plasticizer in the manufacture of bioplastics. Manufacture of bioplastics using the method of pouring a solution with varying concentrations of starch banana weevil (5% w/v and 7% w/v), variations of the addition of glycerin (1 ml, 3 ml, 5 ml and 7 ml), and a variety of gelatinization temperature (60°C, 70°C, and 80°C). Analysis of bioplastics include FTIR testing, tensile strength that is supported by SEM analysis. The results obtained in the analysis of FTIR does not form a new cluster on bioplastics starch banana weevil, but only a shift in the recharge area only, it is due to the addition of O-H groups originating from water molecules that enter the polysaccharide through a mechanism gelatinitation that generates interaction hydrogen bonding strengthened. The maximum tensile strength of bioplastics produced at a concentration of starch 7% w/v, 1 ml glycerine and gelatinization temperature of 80°C is 3,430 MPa. While the tensile strength bioplastic decreased with increasing glycerin which can be shown from the results of SEM where there is a crack, indentations and lumps of starch insoluble.

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