Purpose

Effective management of the issues related to increasing water scarcity in semi-arid regions needs special attention to minimize the negative influence of water stress conditions and prevent soil degradation to ensure global food security.

Methods

The present study develops an eco-friendly, low-cost superabsorbent hydrogel composite (SHC) through recycling natural fibre using graft polymerization method. Effectiveness of the synthesized SHC for conservation of irrigation water was investigated by measuring its water absorbency in different salt, and pH solutions, reswelling capacity, and the soil–water retention curve (SWRC) of SHC amended soil.

Results

The synthesized SHC showed water absorbency of 342 g/g in distilled water, indicating its suitability for agricultural application. The SHC showed excellent re-swelling characteristics for more than eight alternate wetting–drying cycles. The sensitivity of SHC to different inorganic salt solutions was investigated, which showed its water absorbency higher than 90 g/g at the maximum salinity level permitted for plant growth. The addition of SHC in silt loam soil showed an increase in water availability of 56%, 81%, and 125%, with the SHC concentrations of 0.1%, 0.2%, and 0.4%, respectively.

Conclusion

The addition of SHC had reduced the irrigation water requirement by 29% as compared to bare soil at an optimum application rate of 0.2%. The study promotes the use of synthesized SHC for the conservation of irrigation water, as well as soil ecosystem, with an additional advantage of contributing to the mass utilization of waste materials.

Graphical Abstract

中文翻译：

---

将天然纤维回收为高吸水性水凝胶复合材料，用于保护半干旱地区的灌溉用水

目的

有效管理与半干旱地区日益严重的水资源短缺相关的问题需要特别注意，以尽量减少缺水条件的负面影响并防止土壤退化，以确保全球粮食安全。

方法

本研究通过使用接枝聚合方法回收天然纤维，开发了一种环保、低成本的超吸水水凝胶复合材料（SHC）。通过测量合成 SHC 在不同盐和 pH 溶液中的吸水率、再膨胀能力和 SHC 改良土壤的水土保持曲线 (SWRC)，研究了合成 SHC 对灌溉水保护的有效性。

结果

合成的 SHC 在蒸馏水中的吸水率为 342 g/g，表明其适用于农业应用。SHC 在超过 8 次交替的干湿循环中表现出优异的再溶胀特性。研究了SHC对不同无机盐溶液的敏感性，表明在植物生长允许的最大盐度水平下，其吸水率高于90 g/g。在粉砂壤土中添加 SHC 显示可利用水增加 56%、81% 和 125%，SHC 浓度分别为 0.1%、0.2% 和 0.4%。

结论

与裸土相比，在 0.2% 的最佳施用率下，添加 SHC 使灌溉用水量减少了 29%。该研究促进了使用合成 SHC 来保护灌溉水和土壤生态系统，另外还有一个优势是有助于废物的大规模利用。

图形概要