Author: Srinivas RepalaPublisher:
ISBN:
Category : Buffalo River Watershed (Minn.)
Languages : en
Pages : 188
Book Description
An Investigation of Potential for Groundwater Contamination from Pesticide Leaching in Soils Near the Buffalo River of Clay County, Minnesota
Author: Srinivas RepalaPublisher:
ISBN:
Category : Buffalo River Watershed (Minn.)
Languages : en
Pages : 188
Book Description
Ground-water and soil contamination near two pesticide-burial sites in Minnesota
Author: James R. StarkPublisher:
ISBN:
Category : Groundwater
Languages : en
Pages : 58
Book Description
Contamination of Ground Water by Pesticides
Author: United States. Congress. House. Committee on Public Works and Transportation. Subcommittee on Investigations and OversightPublisher:
ISBN:
Category : Drinking water
Languages : en
Pages : 528
Book Description
The Magnitude and Costs of Groundwater Contamination from Agricultural Chemicals
Author: Elizabeth G. NielsenPublisher:
ISBN:
Category : Agricultural chemicals
Languages : en
Pages : 48
Book Description
Pesticide Leaching in Macroporous Clay Soils
Author: R.P. Scorza JuniorPublisher:
ISBN:
Category :
Languages : en
Pages : 468
Book Description
The presence of macropores (i.e. shrinkage cracks, earthworm and root channels) in the unsaturated zone can enhance pesticide leaching to groundwater and therefore increase the risk of groundwater contamination. In this thesis, experimental and modeling approaches were used to obtain a better understanding of the processes that affect pesticide leaching in cracked clay soils at the field scale. A field experiment (1.2 ha) was conducted to study the movement of water and bromide, and of two pesticides with contrasting mobility (bentazone and imidacloprid). A rapid breakthrough of bromide and pesticides in drain water and groundwater was observed, which is a strong evidence for preferential transport in this soil. Two pesticide leaching models were tested using the data from the field experiment: (i) the chromatographic flow model PEARL and (ii) the preferential flow model MACRO. The calibration of PEARL indicated that a large dispersion length was necessary to simulate bromide leaching in this soil correctly, which implies a large non-uniformity of solute transport. This calibration worked well for the mobile pesticide bentazone but not for imidacloprid, which is moderately adsorbed. So the solute transport in this cracked clay soil could not be described with the convection-dispersion equation even after increasing the dispersion length. The bulk of bentazone leaching was underestimated with MACRO although it simulated the leaching of imidacloprid reasonably well. The fast transport of all substances via macropore flow could be simulated well with MACRO although calibration of some sensitive and difficult to measure parameters was necessary. Considering that preferential flow may depend on the processes at the soil surface, a model that simulates water infiltration, overland flow, macropore flow and water storage at soil surface was developed. Simulations revealed that macropores at the soil surface can receive water before the maximum water storage at soil is reached. Therefore, the frequently used assumption that overland flow only starts after the maximum water storage at soil surface is attained can lead to underestimation of macropore flow for short showers.
Distribution of Major Herbicides in Ground Water of the United States
Author: Evaluating Potential Groundwater Contamination from Contaminated Soils
Author: State Program Briefs
Author: An Assessment of the Potential Pesticide Contamination of Groundwater Utilizing the Surface Soil and Leachp Models
Author: Thomas J. TagueWater Conservation in the 21st Century
Author: American Water Resources Association. Spring SymposiumPublisher:
ISBN:
Category : Water conservation
Languages : en
Pages : 756
Book Description