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Surface irrigation
Published in Mohammad Albaji, Introduction to Water Engineering, Hydrology, and Irrigation, 2022
While surface irrigation can be practiced effectively using the right management under the right conditions, it is often associated with a number of issues undermining productivity and environmental sustainability:Waterlogging – Can cause the plant to shut down delaying further growth until sufficient water drains from the root zone. Waterlogging may be counteracted by drainage, tile drainage, or water table control by another form of subsurface drainage.Deep drainage – Over irrigation may cause water to move below the root zone resulting in rising water tables. In regions with naturally occurring saline soil layers (for example salinity in south-eastern Australia) or saline aquifers, these rising water tables may bring salt up into the root zone leading to problems of irrigation salinity.Salinization – Depending on water quality irrigation water may add significant volumes of salt to the soil profile. While this is a lesser issue for surface irrigation compared to other irrigation methods (due to the comparatively high leaching fraction), lack of subsurface drainage may restrict the leaching of salts from the soil. This can be remedied by drainage and soil salinity control through flushing.
Combating Strategies
Published in Ajai, Rimjhim Bhatnagar, Desertification and Land Degradation, 2022
The water used for irrigation should be checked for salinity because salts will accumulate once the water evaporates. Sometimes, the irrigation water recharges the groundwater table to exceptional levels, thereby causing waterlogging in those areas. In many of the canal irrigated areas, the water table has been found to rise considerably (to less than 2 m) during a short period of time (http://www.fao.org/3/x5871e/x5871e04.html). The groundwater that is close to the soil surface evaporates from the surface leaving behind accumulated salts in the root zone. The salt accumulation can be prevented by adequate drainage. In the absence of natural drainage, artificial drainage (tile systems, open drains, pumped wells) is required to be created.
Remediation of Pesticide Contaminated Soil at Agrichemical Facilities
Published in Richard C. Honeycutt, Daniel J. Schabacker, Mechanisms of Pesticide Movement into Ground Water, 1994
Thomas J. Bicki, Alan S. Felsot
Our experiences with a warehouse fire and the aftermath of firefighting procedures effectively illustrate problems of site assessment and soil remediation, which are necessary to prevent ground water contamination. In April 1990, a pesticide warehouse caught fire within the town of Lexington in McLean County, Illinois. Water used to fight the fire became visibly contaminated by herbicides leaking from fire-damaged containers. The contaminated water began to flow away from the warehouse structure and entered a drainage tile that ran under a nearby field and discharged to surface water. To prevent further runoff of water, the tile inlet was sealed, and earthen berms were placed around the warehouse; the contaminated water was contained between the warehouse and adjacent structures, an automobile dealership on the east and a grain elevator on the west. The color of the water indicated contamination with one or more herbicides. Eventually the water, contained by the berm and buildings, infiltrated into the soil. The top 5 cm of soil in certain areas around the warehouse had a greenish-yellow color which suggested to us the presence of trifluralin. The IEPA ordered a cleanup of contaminated soil located between the buildings. Soil sampling was carried out to assist the IEPA in determining the depth of herbicide leaching. Landfarming of the contaminated soil was advised, and degradation of the most prevalent contaminant, trifluralin, was monitored.
Assessing phosphorus distribution and bioavailability in Lake Decatur, IL
Published in Lake and Reservoir Management, 2020
Marcel L. Dijkstra, Miles J. Corcoran, John J. Sloan, Brittany L. Lutz
The Lake Decatur watershed covers 239,600 hectares with an absolute elevation change of 78 m, resulting in a stream gradient of approximately 0.5 m/km (IEPA 2007). Keefer and Bauer (2005) reported that 82% of the watershed was dedicated to agriculture in 2002. Corn and soybeans accounted for the majority of land use, while rural grassland and other natural and urban land covers accounted for the other uses (IEPA 2007). Overall, the watershed is dominated by cultivated crops (see Figure 1). Installation of agricultural drainage tile forms an efficient pathway for soluble P loading to surface waters. For example, tile drainage was responsible for 49% of soluble P and 48% of total P losses from experimental fields in the Maumee basin (Smith et al. 2015). Similarly, tile drainage in the Big Walnut Creek watershed in central Ohio was responsible for 47% of the discharge, 48% of the dissolved P, and 40% of the total P export from the watershed (King et al. 2015). In some counties in the Decatur watershed, where fields have poorly draining soils, up to 75% of the fields are drained by field tiles (e.g., in Piatt and Macon counties), while counties that have soils with a decent infiltration rate, like Ford County, still have ∼40% tile-drained fields (IEPA 2007). Contributions of P to Lake Decatur originating from tile drainage have not been estimated separately for the TMDL (IEPA 2007) but are accounted for in P loadings from creeks and streams (which also receive other loadings like edge-of-field runoff).