Evaluating salinity distribution in soil irrigated with saline water in arid regions of northwest China

Abstract

a b s t r a c tIn arid and semi-arid regions, salinity is a serious and chronic problem for agriculture. A 3-year field experiment in the arid environment of Xinjiang, northwest China, was conducted to study the salinity change in soil resulting from deficit irrigation of cotton with non-saline, moderate saline and high saline water. The salinity profile distribution was also evaluated by an integrated water, salinity, and nitrogen model, ENVIRO-GRO. The simulated and observed salinity distributions matched well. Results indicated that after 3 years of cotton production, the average salinity in the 1.0-m soil profile was 336% and 547% of the original soil profile, respectively, for moderate saline and high saline water irrigation. If the practices continued, the average soil salinity (EC e ) in the 1.0-m soil profile would approach a steady level of 1.7, 10.8, and 14.7 dS m −1 , respectively, for the treatments receiving irrigation waters of 0.33, 3.62, and 6.71 dS m −1 . It was concluded that deficit irrigation of saline water in this region was not sustainable. Model simulation showed that a big flood irrigation after harvest can significantly reduce the salt accumulation in the soil profile, and that this practice was much more efficient for salinity control than applying the same extra amount of water during the growing season.

Winter Irrigation Effects in Cotton Fields in Arid Inland Irrigated Areas in the North of the Tarim Basin, China

“…Firstly, during the temperature drop process from December to January in the next year, the difference of soil temperature in the 5-cm depth between the non-irrigation treatment and the winter irrigation treatments was not significant. Secondly, during the temperature rise process from January to March, soil temperature rise velocity in the non-irrigation treatment was significantly faster than that in the winter irrigation treatments [18].…”

Salt distribution and the growth of cotton under different drip irrigation regimes in a saline area

“…However, soil salinity impacts about one-third of the total irrigated cropland in Xinjiang (Chen et al, 2010). Specifically, there are still 1.1 × 10 7 ha saline wasteland in Xinjiang, of which 7.27 × 10 6 ha overly saline-sodic soils (Xi et al, 2005).…”

Fertigation for Environmentally Friendly Fertilizers Application: Constraints and Opportunities for Its Application in Developing Countries

“…The fertigation technique has rapidly spread all over the world in the last 40 years [9] as a tool to supply the plant with its daily demand of water and nutrients as required by its specific growth stage throughout its development to achieve maximum efficiency of the fertilizer applied [10]. The main reported benefits of fertigation are: 1) Nutrients and water are supplied near the active root zone which results in greater absorption by the crops, 2) As water and fertilizer are supplied evenly to all the crops there is possibility for getting higher yield, 3) Fertilizer use efficiency is high which helps to save nutrients, 4) By this way, along with less amount of water and saving of fertilizer, time, labour and energy use is also reduced substantially [11]. Using this "spoon feeding" approach to fertilization, the units of fertilizer application in fertigation are calculated on the basis of individual plant demand expressed in units of milligram of nutrient (N, P or K) per day over the entire growing period.…”