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研究了兰州市永登县秦王川灌区中型狼尾草(Pennisetum longissimum var.intermedium)、新疆大叶苜蓿(Medicago sativa)和皮燕麦(Avena sativa)对盐渍土的适应特点及其改盐效应。通过对3种植物不同生育期(播后90d、120d、150d)根际土壤pH值、导电率(EC)、盐分离子及有机质含量的测定,探讨盐渍化土壤影响下耐盐植物根际微环境的变化。结果显示:在盐渍化逆境下,3种植物对于根际土壤微环境均有一定调节作用,生育期内土壤pH值、EC值、Na+、SO2-4、Cl-和Ca2+含量逐渐降低,土壤有机质含量逐渐增加。新疆大叶苜蓿根际土壤pH值变化较为突出,其次是中型狼尾草和皮燕麦,播后150d较播前降幅分别为2.18%、2.06%、1.21%;中型狼尾草根际土壤EC值降幅最大,其次为新疆大叶苜蓿和皮燕麦,播后150d较播前降幅分别为42.69%、33.29%、28.33%;在3个取样期,中型狼尾草根际土壤Na+、SO2-4、Cl-含量变化幅度最大,新疆大叶苜蓿对Ca2+的吸收能力强于中型狼尾草和皮燕麦;中型狼尾草在生长期内根际土壤有机质含量持续增加,新疆大叶苜蓿在生长前期有机质增量较显著,生长中后期增量减缓,根际微环境变化趋于稳定。综合而言,中型狼尾草对盐渍土的适应及改良效应较突出,其次是新疆大叶苜蓿,再次是皮燕麦。
This paper studied the adaptation of Pennisetum longissimum var. Intermedium, Medicago sativa and Avena sativa to saline soil in Qinwangchuan Irrigation Area in Yongdeng County, Lanzhou. Through the determination of rhizosphere soil pH value, conductivity (EC), salt ions and organic matter content at different growth stages (90 days, 120 days and 150 days after sowing), the effects of saline soil on rhizosphere micro Environmental changes. The results showed that under the stress of salinization, all the three species of plants had a certain regulatory effect on rhizosphere soil microenvironment. Soil pH value, EC value, Na +, SO2-4, Cl- and Ca2 + Organic matter content gradually increased. The change of pH in rhizosphere soil of Xinjiang alfalfa was more prominent, followed by medium-sized Pennisetum chinense and Pigeon oat, which decreased by 2.18%, 2.06% and 1.21% respectively 150 days after sowing. The EC value of Rhizosphere soil of Medium Pennisetum decreased Followed by Xinjiang alfalfa and skin oats, the decline rates were 42.69%, 33.29% and 28.33% respectively at 150 days after sowing. In three sampling periods, the content of Na +, SO2-4, Cl- The content of Ca (superscript 2 +) in Xinjiang was the largest, and the absorption capacity of Ca2 + by Xinjiang Medicago sativa was higher than that of medium-sized Pennisetum and Pigeon. The content of organic matter in rhizosphere soil of Pennisetum longosum continued to increase in the growth stage, while the increment of organic matter More significant, slow growth in the late growth, changes in the rhizosphere micro-environment tends to be stable. In summary, medium-sized Pennisetum salinized soil adaptation and improvement of the more prominent, followed by the Xinjiang large-leaf alfalfa, and then the skin oats.