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In order to understand the effects of thinning on the growth of Calligonum arborescens and the soil water-salt distribution in Tarim Desert Highway shelterbelt, a thinning experiment was conducted on an aged and declined C. arborescens woodland in a demonstration section of the shelter-belt, with the growth of C. arborescens and the soil water-salt distribution monitored. Thinning had no effects on the phenophase of C. arborescens, but after thinning, the growth of the current year plant height, crown width, ground diameter, and new branch length of reserved trees was larger than that of the control, and the increment was in the order of planting space 2 m×1 m > 1 m×1 m > the control, with significant differences among the treatments. The assimilation branch surface area in treatments 2 m×1 m and 1 m×1 m were 5. 97 m2 and 5. 22 m2 per plant, respectively, being significantly larger than the control (3. 1 m2 per plant). The soil moisture content in 0-160 cm layer was significantly higher in treatments 2 m×1 m and 1 m×1 m than in the control, and increased obviously with thinning intensity. The soil salt content was in the order of control > planting space 1 m×1 m > 2 m×1 m, and the differences among the treatments were significant. It was suggested that the best reserved plant density after thinning was planting space 2 m×1 m. [ABSTRACT FROM AUTHOR]

A field experiment was conducted to study the effects of sufficient and non-sufficient irrigation with saline water on the soil water-salt distribution and spring corn yield in the middle reach of Shiyanghe River Basin. The results showed that under both sufficient and non-sufficient irrigation, the peak value of soil water content all appeared during irrigation period, and the variation range of the water content was higher under sufficient than under non-sufficient irrigation. Soil salinity was positively correlated with the salinity of irrigation water. At the same salinity of irrigation water, the soil salinity under non-sufficient irrigation was lower than that under sufficient irrigation. Under non-sufficient irrigation, the soil layer with salt accumulation was moved up, but the water and salt contents in 80-100 cm soil layer were less affected by the amount and salinity of irrigation water. Comparing with that under fresh water irrigation, the spring corn yield under saline water irrigation was decreased by 15%-22%. Under non-sufficient irrigation with 9 g·L-1, 6 g·L-1, and 3 g·L-1 of saline water, the average salt content in 1 m soil layer after harvest was decreased by 8.1%, 12.4%, and 18.4%, and the corn yield was only decreased by 3.4%, 6.8%, and 3.0%, respectively, compared with those under sufficient irrigation. [ABSTRACT FROM AUTHOR]