摘要
新疆地处干旱地区,水资源短缺,膜下滴灌作为有效的节水灌溉技术在新疆农业生产中广泛使用。但新疆同时是盐碱化普遍发生的地区,采用滴灌技术后,传统灌溉的灌溉洗盐过程随之消失,且该地区灌溉水矿化度较高,对土壤盐分有一定的补充作用,因此滴灌技术虽然节水增产效果明显,但长期滴灌可能导致土壤盐分积累,降低土壤质量。通过监测一个长期膜下滴灌、面积约为224 km2的农场15a农田土壤盐分含量,对长期膜下滴灌土壤盐分含量的变化进行研究,研究结果可为膜下滴灌土壤盐分管理提供科学依据。以位于新疆北部玛纳斯河流域的新疆生产建设兵团第八师147团农田为研究对象,通过收集该团场自1996年至2010年记录的农田耕层盐分和养分指标的分析数据,利用统计学知识及地理信息系统技术,对不同滴灌年限下土壤耕层盐分变异特征及土壤耕层盐分与其他土壤指标的相关性进行研究。研究表明:(1)在滴灌的第一个3年周期内,土壤耕层盐分平均含量从3.13 g kg-1降低至3.00 g kg-1,降幅达4.2%,但经12年滴灌年限,土壤耕层盐分从3.13 g kg-1升高至4.81 g kg-1,升高了53.7%;(2)在五个监测周期(15 a)内,土壤盐分含量明显上升,研究区土壤耕层盐分含量集中分布在4~10 g kg-1,土壤耕层多为中度盐化土和重度盐化土;(3)长期膜下滴灌导致土壤耕层盐分发生重新分配,全团范围内农田盐分含量分布接近正态分布。本研究条件下,长期膜下滴灌会造成土壤耕层盐分积累,滴灌水携带的盐分对土壤盐分有一定的补充作用;采用2~3年进行一次大水洗盐以及培肥土壤、提高土壤有机质含量对防止滴灌土壤积盐具有重要作用。
【Objective】In Xinjiang,an arid region,water scarcity has promoted extensive use of drip irrigation under plastic film mulch in agricultural production as an effective water-saving technique in this region. However,Xinjiang is also a region where soil salinization is common. With the extensive replacement of conventional irrigation with drip irrigation,the benefit of the former washing salts off the soil disappeared. Moreover,the irrigation water in this region is quite high in mineralization and ready to supply the soil with salt. So,although the effect of drip irrigation saving water and increasing yield is quite obvious,long-term adoption of the technique may lead to salt accumulation in the soil,thus lowering soil quality. This paper is oriented to explore impacts of 15-year long-term drip irrigation on soil salinity or soil salt content of the field in an attempt to provide certain scientific basis for management of soil salt under mulched drip irrigation in this region. 【Method】A tract of farmland,around 224 km^2 in area was delineated in Regiment 147,Division Eight of the Xinjiang Production and Construction Corp,in the Manas River Basin,North Xinjiang for the study. The data of salt contents and soil available nutrient contents in the plow layer accumulated during the years from 1996 to 2010 of the tract of farmland were analyzed statistically with the aid of GIS technology to characterize variation of soil salt in the plow layer and relationship between soil salt and other soil indices in the plow layer relative to irrigation history. 【Result】Results show：（1）soil salt content in the plow layer decreased from 3.13 g kg^-1 to 3.00 g kg^-1 or by 4.2% in the first 3 years of drip irrigation,but it rose back up to 4.81 g kg^-1 or 53.7% at the end of the study;（2）after 15 years of drip irrigation,soil salt content in the plow layer of the study region increased significantly,varying mainly in the range of 4~10 g kg^-1,and a large proportion of the plow layer soil could be sorted as moderately or heavily salinized soil;and（3）long-term mulched drip irrigation in the arid region led to redistribution of soil salt in the plow layer,approaching to normal distribution in the scope of the regiment as a whole. 【Conclusion】Under the condition of the study,long-term mulched drip irrigation has led to salt accumulation in the plow layer,because the water used in drip irrigation carries some salt,which may serve as supplement to soil salinity. It is,therefore,recommended to flood the field to wash soil salt off every two or three years in areas under long-term mulched drip irrigation,and to build up soil fertility and soil organic matter content,which may play a positive role in controlling soil salt accumulation due to drip irrigation in this region.
出处
《土壤学报》
CAS
CSCD
北大核心
2017年第6期1386-1394,共9页
Acta Pedologica Sinica
基金
国家重点研发计划(2017YFD0201808)
国家自然科学基金项目(31471947)资助~~
关键词
长期膜下滴灌
耕层土壤
盐分含量
147团
Long-Term mulched drip irrigation
Soil plow layer
Soil salt content
Regiment 147
