Evaluation of mulched drip irrigation for cotton in arid Northwest China

Abstract

Field experiments were conducted in arid Southern Xinjiang, Northwest China, for 3 years to evaluate sustainable irrigation regimes for cotton. The experiments involved mulched drip irrigation during the growing season and flood irrigation afterward. The drip irrigation experiments included control experiments, experiments with deficit irrigation during one crop growth stage, and alternative irrigation schemes in which freshwater was used during one growth stage and relatively saline water in the others. The average cotton yield over 3 years varied between 3,575 and 5,095 kg/ha, and the irrigation water productivity between 0.91 and 1.16 kg/m 3 . Crop sensitivities to water stress during the different growth stages ranged from early flowering-belling (most sensitive) [ seedling [ budding [ late flowering-belling (least sensitive), while sensitivities to salt stress ranged from late flowering-belling [ budding [ seedling [ early flowering-belling. Although mulched drip irrigation during the growing season caused an increase in salinity in the root zone, flood irrigation after harvesting leached the accumulated salts to below background levels. Numerical simulations, based on the 3-year experiments and extended by another 20 years, suggest that mulched drip irrigation using alternatively fresh and brackish water during the growing season and flood irrigation with freshwater after harvesting is a sustainable irrigation practice that should not lead to soil salinization.

Water Use Efficiency in Saline Soils under Cotton Cultivation in the Tarim River Basin

“…Southern Xinjiang had an average cotton yield over three years from 3.6 to 5.1 t·ha with a low EC in the top 30 cm soil from 3 to 11 dS·m −1 [43]. As research mentioned above, our WUE data were lower (0.53 kg·m ), except for WUE and IWUE data at Korla.…”

Soil water and salinity dynamics under sprinkler irrigated almond exposed to a varied salinity stress at different growth stages

“…The distribution of soil solution salinity (EC sw ) was simulated as a non-reactive solute (Ramos et al, 2011;Phogat et al, 2012;Phogat et al, 2014;Wang et al, 2014). These studies demonstrated a good prediction of salinity under intensive irrigation and fertigation, similar to practices in the region under study.…”

Identifying the future water and salinity risks to irrigated viticulture in the Murray-Darling Basin, South Australia

“…The threshold and slope model parameters were obtained from the previous regional study (Zhang et al, 2002) evaluating salinity thresholds (EC e = 2.1 dS/m) and percent reductions (12.8%) in different root stocks of grapevine. The temporal and spatial distribution of soil solution salinity (EC sw ) was modeled as a non-reactive solute (e.g., Ramos et al, 2011;Wang et al, 2014;Phogat et al, 2014). These studies demonstrated that this approach could be successfully used in environments under intensive irrigation and fertigation management.…”