Salt distribution and plant uptake under drip and sprinkler irrigation with saline water

摘要

Spatial and temporal distributions of soil salinity are dynamic functions of irrigation methods and plant water extraction. Differences in irrigation methods can also affect plant salt uptake during irrigation with brackish saline water. This studywas conducted to determine the characteristics of salt distributions under drip and sprinkler irrigation regimes and to correlate these distributions and irrigation methods with salt concentrations in soybean plants. Results indicated that more salt accumulated in the soil profile in the drip than in the sprinkler irrigation plot. Under salinity treatment, higher concentrations of Na~+ was found in roots than in leaves or stems, and significantly higher concentrations of Ca~(2+) were found in plant leaves than in the stems or roots. Higher concentrations of Cl~- were found in leaves and stems in the sprinkler than drip irrigation plots, indicating strong foliar uptake of Cl~-.For irrigation with saline water, drip irrigation may be more suitable for salt sensitive plant species susceptible to foliar salt damage. Sprinkler irrigation can be used for more salt tolerant plants and can create more leaching, leaving less residual salt in the soil profile at the end of the growing season.