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1. Study on formation and expansion condition of hidden soil cavity under condition of groundwater exploitation in karst areas

Author:
Wei, Yongyao; Sun, Sulin
Source:
Environmental earth sciences 2017 v.76 no.7 pp. 282
ISSN:
1866-6280
Subject:
drawdown,   etc   ; analytical methods; groundwater; karsts; mechanics; soil;     Show all 6 Subjects
Abstract:
... This paper uses an analytical method to analyze soil cavity forming conditions and the associated mechanics. On this basis, the paper studies the soil cavity expansion rule and reveals the nature of the soil cave collapse from the mechanism angle. The results show the following: (1) the spalling force caused by pumping at different points around a soil cavity varies. The nearer the point to the pu ...
DOI:
10.1007/s12665-017-6601-1

2. In-well time-of-travel approach to evaluate optimal purge duration during low-flow sampling of monitoring wells

Author:
Harte, Philip T.
Source:
Environmental earth sciences 2017 v.76 no.6 pp. 251
ISSN:
1866-6280
Subject:
drawdown,   etc   ; groundwater; groundwater flow; hydraulic conductivity; models; monitoring; sampling; wells;     Show all 8 Subjects
Abstract:
... A common assumption with groundwater sampling is that low (<0.5 L/min) pumping rates during well purging and sampling captures primarily lateral flow from the formation through the well-screened interval at a depth coincident with the pump intake. However, if the intake is adjacent to a low hydraulic conductivity part of the screened formation, this scenario will induce vertical groundwater flow t ...
DOI:
10.1007/s12665-017-6561-5

3. Fully coupled three-dimensional nonlinear numerical simulation of pumping-induced land movement

Author:
Zhang, Yun; Wu, Jichun; Xue, Yuqun; Wang, Zhecheng
Source:
Environmental earth sciences 2017 v.76 no.16 pp. 552
ISSN:
1866-6280
Subject:
drawdown,   etc   ; aquifers; groundwater; groundwater extraction; groundwater flow; hydraulic conductivity; mathematical models; tensile strength;     Show all 8 Subjects
Abstract:
... Excessive groundwater extraction can cause aquifer systems to move three-dimensionally. Based on the equilibrium of soil skeleton and continuity of groundwater flow, a fully coupled nonlinear three-dimensional mathematical model has been constructed, which incorporates the prevalent nonlinear mechanical and hydraulic properties of aquifer systems. The horizontal and vertical displacements with reg ...
DOI:
10.1007/s12665-017-6891-3

4. Use of tree rings as indicator for groundwater level drawdown caused by tunnel excavation in Zhongliang Mountains, Chongqing, Southwest China

Author:
Zheng, Wei; Wang, Xiuli; Tang, Ya; Liu, Huang; Wang, Mei; Zhang, Lanjun
Source:
Environmental earth sciences 2017 v.76 no.15 pp. 522
ISSN:
1866-6280
Subject:
drawdown,   etc   ; Pinus; aquifers; dendrochronology; environmental impact; groundwater; growth rings; karsts; mountains; social change; tree growth; trees; water table; China;     Show all 14 Subjects
Abstract:
... Tunnel excavation causes geological, hydrological, environmental and social changes. The effects of groundwater level changes caused by tunnelling on tree growth have been poorly understood. Dendrochronology was used to evaluate the impact of groundwater level drawdown on tree growth. Tree cores of Masson pines were collected from the areas affected by tunnel construction in the Zhongliang Mountai ...
DOI:
10.1007/s12665-017-6859-3

5. Degradation of groundwater quality in coastal aquifer of Sabratah area, NW Libya

Author:
Alfarrah, Nawal; Berhane, Gebremedhin; Bakundukize, Charles; Walraevens, Kristine
Source:
Environmental earth sciences 2017 v.76 no.19 pp. 664
ISSN:
1866-6280
Subject:
drawdown,   etc   ; anhydrite; aquifers; chlorides; coasts; electrical conductivity; freshwater; groundwater; gypsum; intensive farming; irrigation; magnesium; nitrates; nitrogen fertilizers; pollution; potassium; risk; saline water; saltwater intrusion; sea level; sewage; shorelines; sodium; sulfates; urbanization; water quality; water table; wells; Libya;     Show all 29 Subjects
Abstract:
... Overextraction of groundwater is widely occurring along the coast where good quality groundwater is at risk, due to urbanization, tourist development and intensive agriculture. The Sabratah area at the northern central part of Jifarah Plain, Northwest Libya, is a typical area where the contamination of the aquifer in the form of saltwater intrusion, gypsum/anhydrite dissolution and high nitrate co ...
DOI:
10.1007/s12665-017-6999-5

6. Changes in flow and chemistry of groundwater heavily affected by human impacts in the Baiyangdian catchment of the North China Plain

Author:
Yuan, Ruiqiang; Wang, Shiqin; Wang, Peng; Song, Xianfang; Tang, Changyuan
Source:
Environmental earth sciences 2017 v.76 no.16 pp. 571
ISSN:
1866-6280
Subject:
drawdown,   etc   ; air pollution; alluvial plains; anthropogenic activities; aquifers; drainage; groundwater; humans; hydrogeochemistry; ions; isotopes; mixing; nitrates; nitric oxide; sediments; sewage; sodium; soil; sulfates; surface water; surveys; water table; watersheds; China;     Show all 24 Subjects
Abstract:
... To identify impacts of air pollution, sewage drainage, agricultural production, over-pumping and reservoir storage on groundwater, a field survey was conducted in the Baiyangdian catchment of the North China Plain. Major ions and water isotopes were measured. Results show that hydrological processes and hydrogeochemical evolution of shallow groundwater were greatly disturbed by human activities. E ...
DOI:
10.1007/s12665-017-6918-9