长期咸水滴灌对灰漠土理化性质及棉花生长的影响

为揭示长期咸水滴灌对灰漠土物理化学特性及棉花生长的影响,研究了咸水灌溉11 a后土壤盐分、容重、水力特性、棉花耐盐生理特征及产量.试验设置3个灌溉水盐度水平:0.35 dS·m-1(淡水)、4.61 dS·m-1(微咸水)和8.04 dS·m-1(咸水).研究表明:与淡水灌溉相比,微咸水和咸水灌溉显著增加土壤容重、盐分...

Effects of long|term saline water drip irrigation on physicochemical properties and cotton growth in grey desert soil

To reveal the effect of long|term saline water irrigation on physicochemical properties of grey desert soil, cotton growth and yield in Xinjiang, a 11-year field experiment for evaluating long|term saline water irrigation effects on soil salinity, bulk density, hydraulic characteristics, physiological characteristics of salt tolerance and seed cotton yield was conducted. The experimental design was three irrigation water salinity treatments of 0.35 dS·m^-1, 4.61 dS·m^-1, and 8.04 dS·m^-1, representing fresh water, brackish water, and saline water, respectively. The results showed that irrigation with brackish water and saline water significantly increased soil bulk density, salinity, pH and soil water content, but significantly reduced soil porosity, TN and SOM. Soil saturated hydraulic conductivity was significantly lower by 45% and 60% in the brackish water and saline water treatments than that in the fresh water treatment, and the volumetric water content also increased when irrigation water salinity increased. The brackish water and saline water irrigation significantly reduced leaf area, leaf water potential, stomatal conductance, chlorophyll content, and ratio of dry|and|wet mass when compared to fresh water irrigation. In addition, the leaf water potential was significantly lower by 43.34% and 63.46% in the brackish water and saline water treatments than that in the fresh water treatment, respectively. The brackish water and saline water irrigation significantly increased the relative electrical conductivity (REC), MDA content of cotton leaves as well as the activities of SOD, POD and CAT. Proline content was significantly increased with increasing salinity of irrigation water, when compared to the fresh water irrigation treatment, proline content under brackish water treatment was increased by 69.52%, and proline content under saline water treatment was increased by 212%, respectively. In general, the fresh water irrigation also produced the highest biomass and seed cotton yield. The biomass reduction caused by using the brackish water was 14.15% and by using saline water was 32.88% lower than those of using the fresh water. Seed cotton yield were 12.60% and 25.72% lower under brackish and saline water irrigation treatment than that under fresh water irrigation treatment, respectively. In summary, long|term brackish water and saline water irrigation significantly increased soil salinity, resulting in a decrease in soil nutrients and a significant decrease in availability of soil water, and ultimately reduced cotton biomass and yield.