塔里木河下游地区滴灌沙枣防护林地土壤盐分分布特征  

Effect of Drip Irrigation on Forest Soil Salinity Distribution in Lower Reaches of Tarim River,China

作　　者：赵新风[1] 王炜[1] 张涛[2] 白元[1] 徐海量[1] 

机构地区：[1]中国科学院新疆生态与地理研究所,新疆乌鲁木齐830011 [2]新疆生产建设兵团农二师34团林业工作站,新疆库尔勒841507

出　　处：《中国沙漠》2012年第3期763-770,共8页Journal of Desert Research

基　　金：水利部公益性行业科研专项(201101049);国家自然科学基金项目(30970549;41171427)资助

摘　　要：为了研究不同滴灌措施对极端干旱区防护林土壤盐分的淋洗作用,以沙枣(Elaeagnus angustifolia)防护林作为研究对象,对塔里木河下游喀拉米吉绿洲沙枣防护林开展了灌溉与不灌溉、不同滴头距离、不同滴灌年限处理的试验。结果表明:①不灌溉林地土壤盐分含量与流动沙丘相似,流动沙丘土壤盐分分布的空间异质性大于不灌溉林地。滴灌林地土壤含盐量低于不灌溉林地。②1.5m滴头距离处理与其他处理相比压盐碱效果显著(P<0.01)。1.5m与3m滴头距离处理在50cm土体中含盐量差异达极显著水平(P<0.01),前者比流动沙丘低30.5%～32.7%、后者比流动沙丘高17.1%～13.3%。与3m滴头距离处理相比,1.5m滴头距离处理产生水盐运移的"互作"影响,盐峰下移。③滴灌后的第1、2、3年,林地的土壤盐分分别下降至30cm、50cm和70cm以下,基本对沙枣根系生长没有影响。随着滴灌次数增加,根系生物量逐渐增大,根系附近土壤盐分逐渐减少。滴灌能使防护林的根系分布上移,大部分在10～65cm土层内,土层越深,林木的根系越少。④灌水季节末期,不同林龄的防护林在120cm土体的含盐量表现为:1a林>2a林>6a林,说明滴灌对林龄大的防护林淋洗效果更为明显;非灌溉季节里,防护林的林龄越大,其土壤盐分表聚现象越明显。We analyzed the soil salinity leaching characteristics of shelterbelts under drip irrigation in the Kalamiji oasis in the lower reaches of Tarim River, northwest of China. The results indicate that： （1） Soil salinity decreased at 0-20 cm soil layer and accumulated at 20-50 cm soil layer under drip irrigation Soil salinity in the artificial shelterbelts without irrigation was similar to that in sand dunes. Spatial heterogenei- ty of soil salinity in sand dunes was greater than that in shelterbelts with no irrigation. Soil salinity was low- er in shelterbelts with irrigation than in shelterbelts without irrigation. （2） Effect of controlling salinity leaching under 1.5-m emitter distance treatment was much significant than that under other treatments （P 〈0.01）. The difference of soil salinity contents at 50 cm soil layer between 1.5-m and 3-m emitter distance was significant （P〈0.01）. Salinity under 1.5 m distance was lower than that in sand dunes by 30.5% -- 32.7 %, salinity under 3 m distance was higher than that in sand dunes by 17.1%-13.3 %. Compared with the treatment of 3-m emitter distance, the position of the highest salinity layer moved downward under 1.5- m emitter distance, which because of the ＂ interaction＂ impact between salt and water. （3） Salinity was leached below 30 cm, 50 cm and 70 cm respectively in shelterbelts when drip irrigation lasted for 1-year, 2- years and 3-years. There almost no influence of salinity on roots in these depths above. Root biomass in- creased and soil salinity near the roots decreased gradually with the drip irrigation days. Most of Elaeagnus angustifol, ia roots of 1--3 years are distributed within the 10--65 cm soil layer. Location of roots can be moved upward under long term drip irrigation condition. （4） In non-irrigation seasons, mean value of salini- ty in 0--120 cm soil body presented： 1-year shelterbelt〉2-year shelterbelt〉6-year shelterbelt, indicate that the leaching effect was more apparent in old forest. Phenomenon of ＂s

关 键 词：绿洲防护林 滴灌 洗盐作用 塔里木河下游 

分 类 号：S153[农业科学—土壤学]