Effects of irrigation with HCH-contaminated water on crop performance and HCH accumulation in plant and soil.

Lindane production is very ineffective since, for each ton of lindane obtained, between 6 and 10 tons of hexachlorocyclohexane (HCH) isomers and other toxic compounds are produced. Due to the disposal of these residues, contaminated zones still exist, and many dumpsites are close to rivers and water reservoirs. The current study examines the consequences of irrigating pea, maize, and alfalfa, with water containing different HCH concentrations on the accumulation of HCH in plant material and soils.

Coupled DSSAT-SWAT models to reduce off-site N pollution in Mediterranean irrigated watershed.

In any agricultural watershed, best management practices (BMPs) are a conservational way to reduce non-point source pollution and, soil and water resources sustainability. The objectives of this study were to calibrate and validate the modified Soil and Water Assessment Tool (SWAT) in the Violada Watershed (VW), Spain and assess the BMPs scenarios, already tested at field scale, using the Decision Support System for Agro Technology Transfer model (DSSAT), and finally, to access the BMPs impact on water quality off-site. To this end, daily streamflow discharge and NO concentration were measured at VW outlet from October 2015 to September 2017 for model evaluation.

Risk of phosphorus desorption from Canadian agricultural land: 25-year temporal trend.

Phosphorus (P) use in excess of crop needs may impact surface water quality and contribute to eutrophication. However, P loss from agricultural land to water has never been estimated at the Canadian national scale. In this paper, the risk of P desorption from Canadian agricultural land is assessed by the source component of the indicator of risk of water contamination by P (IROWC-P).

Indicator of risk of water contamination by phosphorus from Canadian agricultural land.

The indicator of risk of water contamination by phosphorus (IROWC_P) is designed to estimate where the risk of water P contamination by agriculture is high, and how this risk is changing over time based on the five-year period of data Census frequency. Firstly developed for the province of Quebec (2000), this paper presents an improved version of IROWC_P (intended to be released in 2008), which will be extended to all watersheds and Soil Landscape of Canada (SLC) polygons (scale 1:1, 000, 000) with more than 5% of agriculture. There are three objectives: (i) create a soil phosphorus saturation database for dominant and subdominant soil series of SLC polygons--the soil P saturation values are estimated by the ratio of soil test P to soil P sorption capacity; (ii) calculate an annual P balance considering crop residue P, manure P, and inorganic fertilizer P--agricultural and manure management practices will also be considered; and (iii) develop a transport-hydrology component including P transport estimation by runoff mechanisms (water balance factor, topographic index) and soil erosion, and the area connectivity to water (artificial drainage, soil macropores, and surface water bodies).