The influence of unsaturated zone drainage status on denitrification and the redox succession in shallow groundwater

2019 ◽  
Vol 660 ◽  
pp. 1232-1244 ◽  
Author(s):  
J.C. Clague ◽  
R. Stenger ◽  
U. Morgenstern
Keyword(s):  
Unsaturated Zone ◽  
Shallow Groundwater

scholarly journals Groundwater vulnerability assessment and mapping in shallow groundwater

2021 ◽  
Vol 926 (1) ◽  
pp. 012047
Author(s):  
K Aribowo ◽  
W Wilopo ◽  
D H Barianto
Keyword(s):  
Land Use Planning ◽  
Unsaturated Zone ◽  
Shallow Groundwater ◽  
Primary Source ◽  
Groundwater Vulnerability ◽  
Research Area ◽  
A Value ◽  
Groundwater Vulnerability Assessment ◽  
Vulnerability Map ◽  
Very High

Abstract The increasing population density can contaminate groundwater. So far, groundwater is still the primary source to fulfill clean water and drinking water in Muntilan, Salam, and Ngluwar Sub-District. Studies on groundwater vulnerability are essential to minimize the contamination risks as a piece of basic information for land use planning. This research aims to assess groundwater vulnerability in Muntilan, Salam, and Ngluwar Sub-District. The simple vertical vulnerability (SVV) method with GIS was selected to develop a groundwater vulnerability map. The parameters of this method consist of the type of soil/rock, the thickness of the water-unsaturated zone, and the recharge value. The results show that the research area can be divided into three vulnerability classes: very low, moderate, and high groundwater vulnerability. Very low groundwater vulnerability has a value of more than 70 with very high protection effectiveness. The class is distributed in Muntilan and Salam Sub-Districts. Moderate groundwater vulnerability has a value less than 35 to 65 with moderate protection effectiveness, and high groundwater vulnerability has a value ranging from 24 to 35 with low protection effectiveness. Both of the class is evenly distributed in Muntilan, Ngluwar and Salam Sub-Districts.

Modeling Unsaturated Zone Movement of Aldicarb Residues from Applications to Potatoes in Eastern Canada

1987 ◽  
Vol 22 (1) ◽  
pp. 99-106 ◽  
Author(s):  
Russell L. Jones ◽  
Tammara L. Estes
Keyword(s):  
Drinking Water ◽  
Unsaturated Zone ◽  
Prince Edward Island ◽  
Shallow Groundwater ◽  
Buffer Zone ◽  
Zone Model ◽  
Eastern Canada ◽  
Water Wells ◽  
Simulation Results ◽  
Drinking Water Guideline

Abstract The unsaturated zone model PRZM was used to simulate movement of aldicarb residues resulting from applications to potatoes grown in Ontario, Quebec and Prince Edward Island. These simulations suggest aldicarb residues will not generally enter shallow groundwater at levels exceeding the drinking water guideline. In instances where residues do enter shallow groundwater the resulting magnitude will be sufficiently small to permit degradation of residues to below guideline concentrations before moving beyond the required 150 m buffer zone around drinking water wells. The simulation results are consistent with existing potable well monitoring data.

scholarly journals Heat transport of diurnal temperature oscillations upon river-water infiltration investigated by fiber-optic high-resolution temperature profiling

2011 ◽  
Vol 8 (3) ◽  
pp. 6257-6289
Author(s):  
T. Vogt ◽  
M. Schirmer ◽  
O. A. Cirpka
Keyword(s):  
River Water ◽  
Heat Transport ◽  
Unsaturated Zone ◽  
Riparian Zone ◽  
Shallow Groundwater ◽  
Temporal Variations ◽  
Water Infiltration ◽  
Diurnal Temperature ◽  
Temperature Oscillations ◽  
Losing River

Abstract. River-water infiltration is of high relevance for hyporheic and riparian groundwater ecology as well as for drinking water supply by river-bank filtration. Heat has become a popular natural tracer to estimate exchange rates between rivers and groundwater. However, quantifying flow patterns and velocities is impeded by spatial and temporal variations of exchange fluxes, insufficient sensors spacing during field investigations, or simplifying assumptions for analysis or modeling such as uniform flow. The objective of this study is to investigate local heat transport upon river-water infiltration in the riverbed and the adjacent riparian zone of the losing River Thur in northeast Switzerland. Here we have applied distributed temperature sensing (DTS) along optical fibers wrapped around three tubes to measure high-resolution temperature profiles of the unsaturated zone and shallow groundwater. Diurnal temperature oscillations were tracked in the subsurface and analyzed by means of dynamic harmonic regression to extract amplitudes and phase angles. Subsequent calculations of amplitude attenuation and time shift relative to the river signal show in detail vertical and temporal variations of heat transport. In addition, we apply a numerical two-dimensional heat transport model for the unsaturated zone and shallow groundwater to get a better understanding of the observed heat transport processes in the riparian zone. Our results show that heat transfer of diurnal temperature oscillations from the losing river through groundwater is influenced by thermal exchange with the unsaturated zone. Neglecting the influence of the unsaturated zone would cause biased interpretation and underestimation of groundwater flow velocities. In addition, the observed riparian groundwater temperature distribution cannot be described by uniform flow, but rather by horizontal groundwater flow velocities varying over depth.

scholarly journals Using an ETWatch (RS)-UZF-MODFLOW Coupled Model to Optimize Joint Use of Transferred Water and Local Water Sources in a Saline Water Area of the North China Plain

Water ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 3361
Author(s):  
Xianglong Hou ◽  
Shiqin Wang ◽  
Xiaorui Jin ◽  
Mingliang Li ◽  
Mengyu Lv ◽  
...  
Keyword(s):  
Unsaturated Zone ◽  
North China Plain ◽  
North China ◽  
Saline Water ◽  
Regional Scale ◽  
Shallow Groundwater ◽  
Coupled Model ◽  
Water Area ◽  
Water Sources ◽  
Deep Groundwater

In the saline water area of our research, deep groundwater was over-pumped for agricultural irrigation which resulted in a decline of the deep groundwater level and an increase in the shallow groundwater table. Soil salination was also aggravated due to the strong evapotranspiration (ET) in the shallow groundwater areas, where ET removes water vapor from the unsaturated zone (ETu), and the groundwater (ETg). Joint utilities of multiple water sources of transferred water and local shallow and deep groundwater are essential for reasonable management of irrigation water. However, it is still difficult to distinguish ETu and ETg in coupled management of unsaturated zone and groundwater, which account for the water balance in utilities of multiple water sources in a regional scale. In this paper, we used an RS-based ETWatch model as a source of evapotranspiration data coupled with UZF-MODFLOW, an integrated hydrological model of the unsaturated–saturated zone, to estimate the ETg and ETu on a regional scale. It was shown that the coupled model (ETWatch-UZF-MODFLOW) avoids the influence of ETu on the groundwater balance calculation and improves the accuracy of the groundwater model. The model was used in the simulation and prediction of groundwater level. The eastern North China Plain (NCP) was selected as the study area where shallow groundwater was saline water and deep groundwater cone existed. We compared four different scenarios of irrigation methods, including current irrigation scenario, use of saline water, limited deep groundwater pumping, use of multiple water sources of transferred water and local groundwater. Results indicate that the total ETg for the four scenarios in the study area from 2013 to 2030 is 119 × 108 m3, 81.9 × 108 m3, 85.0 × 108 m3, and 92.3 × 108 m3, respectively, and the proportion of ETg to total ET was 6.85%, 4.79%, 4.97%, 5.37%. However, in regions where the groundwater depth is less than 3 m, ETg accounts for 12% of the total ET, indicating that groundwater was one of the main sources of evapotranspiration in shallow groundwater depth area.

scholarly journals Investigating riparian groundwater flow close to a losing river using diurnal temperature oscillations at high vertical resolution

2012 ◽  
Vol 16 (2) ◽  
pp. 473-487 ◽  
Author(s):  
T. Vogt ◽  
M. Schirmer ◽  
O. A. Cirpka
Keyword(s):  
High Resolution ◽  
Groundwater Flow ◽  
Heat Transport ◽  
Unsaturated Zone ◽  
Shallow Groundwater ◽  
Temporal Variations ◽  
Water Infiltration ◽  
Diurnal Temperature ◽  
Temperature Oscillations ◽  
Losing River

Abstract. River-water infiltration is of high relevance for hyporheic and riparian groundwater ecology as well as for drinking water supply by river-bank filtration. Heat has become a popular natural tracer to estimate exchange rates between rivers and groundwater. However, quantifying flow patterns and velocities is impeded by spatial and temporal variations of exchange fluxes, insufficient sensors spacing during field investigations, or simplifying assumptions for analysis or modeling such as uniform flow. The objective of this study is to investigate lateral shallow groundwater flow upon river-water infiltration at the shoreline of the riverbed and in the adjacent riparian zone of the River Thur in northeast Switzerland. Here we have applied distributed temperature sensing (DTS) along optical fibers wrapped around tubes to measure high-resolution vertical temperature profiles of the unsaturated zone and shallow riparian groundwater. Diurnal temperature oscillations were tracked in the subsurface and analyzed by means of dynamic harmonic regression to extract amplitudes and phase angles. Subsequent calculations of amplitude attenuation and time shift relative to the river signal show in detail vertical and temporal variations of heat transport in shallow riparian groundwater. In addition, we apply a numerical two-dimensional heat transport model for the unsaturated zone and shallow groundwater to obtain a better understanding of the observed heat transport processes in shallow riparian groundwater and to estimate the groundwater flow velocity. Our results show that the observed riparian groundwater temperature distribution cannot be described by uniform flow, but rather by horizontal groundwater flow velocities varying over depth. In addition, heat transfer of diurnal temperature oscillations from the losing river through shallow groundwater is influenced by thermal exchange with the unsaturated zone. Neglecting the influence of the unsaturated zone would cause biased interpretation and underestimation of groundwater flow velocities. The combination of high resolution field data and modeling shows the complex hydraulic and thermal processes occurring in shallow riparian groundwater close to losing river sections as well as potential errors sources for interpreting diurnal temperature oscillations in such environments.

Conception of vadose zone research in the area of Goczałkowice reservoir.

2013 ◽  
Vol 2 (1) ◽  
pp. 22-26
Author(s):  
Joanna Czekaj ◽  
Kamil Trepka
Keyword(s):  
Vadose Zone ◽  
Unsaturated Zone ◽  
Vertical Profile ◽  
Structural Model ◽  
Historical Data ◽  
Integrated System ◽  
Nitrate Transport ◽  
Strategic Research ◽  
Research Site ◽  
Observation Wells

Abstract Goczałkowice reservoir is one of the main source of drinking water for Upper Silesia Region. In reference to Water Frame Directive matter since 2010 the strategic research project: „Integrated system supporting management and protection of dammed reservoir (ZiZoZap)”, which is being conducted on Goczałkowice reservoir, has been pursued. In the framework of this project complex groundwater monitoring is carried on. One aspect is vadose zone research, conducted to obtain information about changes in chemical composition of infiltrating water and mass transport within this zone. Based on historical data and the structural model of direct catchment of Goczałkowice reservoir location of the vadose zone research site was selected. At the end of November 2012 specially designed lysimeter was installed with 10 MacroRhizon samplers at each lithological variation in unsaturated zone. This lysimeter, together with nested observation wells, located in the direct proximity, create the vadose zone research site which main aim is specifying the amount of nitrate transport in the vertical profile.

Unsaturated zone characteristics rating for North Carolina

2001 ◽  
Author(s):  
Silvia Terziotti ◽  
Jo Leslie Eimers
Keyword(s):  
North Carolina ◽  
Unsaturated Zone
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