Watering Floodplain Wetlands in the Murray–Darling Basin to Benefit Native Fish A Discussion with Managers

Introduction: The following Standards for Landscape Irrigation Systems replace the previous publication of March 1997. They have been developed by the Irrigation Industry Association of British Columbia to reflect the current minimum Standards for the industry and to provide guidance to its members as a benchmark for their performance. The principles embodied in these Standards apply to all landscape irrigation systems but the special circumstances of some owners or installations may require the development of more customized specifications related to the project. The use of these Standards is intended to encourage efficient and responsible water management and result in irrigation systems that are economical, practical, and sustainable. Owners, designers, and installers of these systems are responsible for the use of a precious and finite resource to maintain healthy and functional landscapes. Accepted industry practice reflects these goals. The Irrigation Industry Association of British Columbia accepts no liability arising from the use of these Standards in contractual relationships between parties to an irrigation project.

Soil hydrology determines the water–soil–plant interactions in the Earth’s system because porous medium acts as an interface within the atmosphere and lithosphere; regulates main processes such as runoff discharge, aquifer recharge, movement of water, and solutes into the soil; and ultimately the amount of water retained and available for plants growth. Soil hydrology can be strongly affected by land management. Therefore, investigations aimed at assessing the impact of land management changes on soil hydrology are necessary, especially to optimize water resources. This Special Issue collects 12 original contributions addressing the state-of-the-art advances in soil hydrology for sustainable land management. These contributions cover a wide range of topics including (i) the effects of land use change, (ii) water use efficiency, (iii) erosion risk, (iv) solute transport, and (v) new methods and devices for improved characterization of soil physical and hydraulic properties. They include both field and laboratory experiments as well as modelling studies. Different spatial scales, i.e., from field to regional scales, and a wide range of geographic regions are also covered. The collection of these manuscripts presented in this Special Issue provides a relevant knowledge contribution for effective saving water resources and sustainable land management.

In the soil columns experiment, A and B horizon materials from sandy loam, silt loam, and clay loam soils were pre-treated with water having salinity and sodicity typical of PRB CBM water or of Powder River (PR) water currently used for irrigation in the basin. Tension infiltrometer measurements were used to determine infiltration flux, first using pre-treatment water, and subsequently deionized (DI) water, simulating rainwater. Measurements were compared by pre-treatment water, horizon, and soil type. Under pre-treatment water testing, the sandy loam and clay loam soils pre-treated with CBM water exhibited smaller infiltration flux values than when pre-treated with PR water. Only the sandy loam soil showed a greater decrease in infiltration flux with DI water on soils pre-treated with CBM relative to PR water pre-treated soils. There was no difference in infiltration flux decrease with DI water between A and B horizon soils, or between smectite and non-smectite soils.

The main pressures from agriculture are linked to diffuse pollution from nutrients and chemicals, water abstraction and hydromorphological changes. Often several pressures act at the same time, potentially increasing the range of ecological impacts. According to information reported under the WFD, around one third of surface water bodies fail to achieve good status because of one or several of these pressures.