• ISSN 1008-505X
  • CN 11-3996/S
张晶, 杨树青, 郑彦, 王波, 马守良, 张万锋. 生物措施显著提高农牧交错区盐渍土的暗管排盐效果[J]. 植物营养与肥料学报, 2022, 28(12): 2299-2309. DOI: 10.11674/zwyf.2022197
引用本文: 张晶, 杨树青, 郑彦, 王波, 马守良, 张万锋. 生物措施显著提高农牧交错区盐渍土的暗管排盐效果[J]. 植物营养与肥料学报, 2022, 28(12): 2299-2309. DOI: 10.11674/zwyf.2022197
ZHANG Jing, YANG Shu-qing, ZHENG Yan, WANG Bo, MA Shou-liang, ZHANG Wan-feng. Biological measures significantly improve the salt discharge effect of subsurface pipes in saline soil of the agro-pastoral ecotone in Inner Mongolia[J]. Journal of Plant Nutrition and Fertilizers, 2022, 28(12): 2299-2309. DOI: 10.11674/zwyf.2022197
Citation: ZHANG Jing, YANG Shu-qing, ZHENG Yan, WANG Bo, MA Shou-liang, ZHANG Wan-feng. Biological measures significantly improve the salt discharge effect of subsurface pipes in saline soil of the agro-pastoral ecotone in Inner Mongolia[J]. Journal of Plant Nutrition and Fertilizers, 2022, 28(12): 2299-2309. DOI: 10.11674/zwyf.2022197

生物措施显著提高农牧交错区盐渍土的暗管排盐效果

Biological measures significantly improve the salt discharge effect of subsurface pipes in saline soil of the agro-pastoral ecotone in Inner Mongolia

  • 摘要:
    目的 研究工程与生物改良措施对内蒙古河套灌区下游农牧交错区盐渍土理化性质的协同改善效果,以提高盐渍土的改良效益。
    方法 田间试验于2020和2021年展开,试验地暗管埋深0.8 m,间距20 m。生物措施处理为种植甜高粱、苏丹草和苜蓿3种耐盐牧草,以无植物裸地为对照(CK)。植物收获后,测定了植物地上部和地下部生物量,分析了0—20、20—40、40—60 cm土层土壤容重、全盐量、各盐分离子含量,并明晰了土壤盐离子运移特征及植物脱盐效果。
    结果 与2020年播前相比,结合暗管排水,苜蓿、甜高粱、苏丹草处理收获后0—20 cm土层容重较试验前分别降低了16.77%、13.57%、14.73%,土壤容重降幅从表层到深层依次减小,3个土层的平均降幅是CK的6.37~7.88倍;苜蓿、苏丹草、甜高粱和CK处理0—20 cm土层脱盐率分别为61.42%、56.69%、39.96%和23.43%,3个工程–生物双重措施处理较暗管单一措施对照的脱盐率高16.53%~37.99%,20—40、40—60 cm土层的脱盐率依次降低。土壤主导盐分离子SO42−、Na++K+、Cl脱盐率较高,平均为41.91%~57.47%、33.4%~55.39%、31.05%~53.49%,同一处理各主导盐分离子的脱盐率较为接近。苜蓿地上部分Na+、Ca2+、Mg2+、SO42−、Cl含量显著高于甜高粱和苏丹草。2021年苜蓿、甜高粱、苏丹草处理分别较2020年增产51.81%、28.51%、24.35%。2年刈割苜蓿、甜高粱、苏丹草携出的盐分量分别为30.00、66.92、68.05 g/m2,分别占土壤总脱盐量的1.59%、5.13%、3.32%。
    结论 植物措施可显著提升工程措施降低土壤容重和全盐量的效果,尤其在0—20 cm土层。植物通过刈割带走的盐分含量相较淋洗盐分含量微不足道,植物通过根系改善了土壤结构从而促进盐分淋洗出耕层,因此主要根据植物促进土壤盐分淋洗作用的强弱来筛选适宜的耐盐植物。种植苜蓿降低土壤容重和全盐量的效果最优,因此在河套灌区下游农牧交错区,采用暗管排水配合种植苜蓿是改良盐渍土的有效措施。

     

    Abstract:
    Objectives Biological measurements were studied to improve the desalting effect of engineering in saline soil of the lower reaches of agro-pastoral ecotone in the Inner Mongolia Hetao irrigation area.
    Methods Field experiments were carried out in 2020 and 2021. Drainage pipes were buried at 0.8 m depth, running 20 cm apart. The biological treatments were salt-tolerant plants, including Sorghum bicolor, Sorghum sudanense, Medicago sativa, and no plant plot was used as the control (CK). After harvest, plants' aboveground and belowground biomass were recorded. The soil bulk density, total salt and individual ion content in 0−20 cm, 20−40 cm, and 40−60 cm soil layers were measured.
    Results Combined with subsurface pipe, the bulk density of 0−20 cm soil layer in M. sativa, S. bicolor, and S. sudanense decreased after harvest by 16.77%, 13.57%, and 14.73%, respectively, compared with the values recorded before the experiment. The bulk density of the soil treated with the three forage plants decreased from the surface to the deeper layer, with an average of 6.37−7.88 times that of CK. Compared with the values recorded before sowing, the desalting rates of M. sativa, S. sudanense, S. bicolor, and CK in 0−20 cm soil layer after harvest were 61.42%, 56.69%, 39.96%, and 23.43%, respectively. The desalting rates of the three engineering and biological dual measures were 16.53%−37.99% higher than that of subsurface pipe single measure control. The desalting rate in 20−40 cm and 40−60 cm soil layers decreased successively. The desalting rates of SO42−、Na++K+、Cl were relatively high. The average desalting rates of SO42−, Na++K+, and Cl were 41.91%−57.47%, 33.4%−55.39% and 31.05%−53.49%, respectively. The desalting rates of all ions in the same treatment were similar. The contents of Na+, Ca2+, Mg2+, SO42− and Cl in the aboveground biomass of M. sativa were significantly higher than those in S. bicolor and S. sudanense. The yields of M. sativa, S. bicolor, and S. sudanense increased in 2021 by 51.81%, 28.51% and 24.35% compared with 2020. The salt content of two years mowed M. sativa, S. bicolor, and S. sudanense was 30.0 g/m2, 66.92 g/m2, and 68.05 g/m2, accounting for 1.59%, 5.13%, and 3.32% of the total soil desalination, respectively.
    Conclusions Plant measures could improve the engineering measures effect n reducing soil bulk density and total salt content, especially in 0−20 cm soil depth. The salt content taken by plants through mowing is negligible compared with that lost through leaching. Plants improve the soil structure through roots and promote salt leaching out of the tillage layer. Therefore, suitable salt-tolerant plants are mainly selected according to the strength of the promoting leaching effect of soil salt. Planting M. sativa produced the best result in reducing soil bulk density and total salt content. Therefore, planting M. sativa is an effective measure of improving salinized soil with subsurface drainage in the agro-pastoral ecotone in the lower reaches of the Hetao irrigation area.

     

/

返回文章
返回