In arid and semi‐arid regions of the world, agricultural production is greatly limited by water scarcity and inefficient water use. Water‐absorbent hydrogels are a technological solution that can retain soil water for plants. A lignin‐based hydrogel as a natural plant‐based water absorbent is prepared from lignin alkali polymers and poly(ethylene glycol) diglycidyl ether (PEGDGE) in adjusted alkali (NaOH) solution. The maximum swelling capacity of the hydrogel is achieved in 1.5 m NaOH with 0.5 mmol PEGDGE g ${}_{\mathrm{lignin}}^{-1}$. Water swelling capacity is 34 g g ${}_{\mathrm{Hydrogel}}^{-1}$ dry weight of hydrogel in distilled water, which is reduced to 53% and 64% in 0.1 m NaCl and 0.1 m CaCl₂ solution, respectively. Biodegradability and phytotoxicity tests show that 6.5% of the sample mass decomposed after 40 days of incubation in soil solution media and the hydrogel is not phytotoxic to wheat seeds. These findings support the use of the lignin‐based hydrogel as an environmentally friendly additive to promote water retention in dry, saline soils. Due to the limitations of this study, further assessments are needed in order to understand the efficiency of lignin‐based hydrogel application in different soils with different biota.

中文翻译：

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用于农业土壤的木质素基水凝胶的开发和表征：初步证据

在世界干旱和半干旱地区，缺水和低效用水极大地限制了农业生产。吸水水凝胶是一种可以为植物保留土壤水分的技术解决方案。木质素基水凝胶是天然植物基吸水剂，由木质素碱聚合物和聚（乙二醇）二缩水甘油醚（PEGDGE）在经调节的碱（NaOH）溶液中制得。在1.5 m NaOH和0.5 mmol PEGDGE g中达到水凝胶的最大溶胀能力${}_{\mathrm{木质素}}^{-\mathrm{1个}}$。水溶胀能力为34 gg${}_{\mathrm{水凝胶}}^{-\mathrm{1个}}$蒸馏水中水凝胶的干重，在0.1 m NaCl和0.1 m CaCl ₂溶液中分别降低至53％和64％。生物降解性和植物毒性测试表明，在土壤溶液培养基中孵育40天后，样品质量的6.5％分解了，水凝胶对小麦种子没有植物毒性。这些发现支持使用木质素基水凝胶作为对环境友好的添加剂来促进在干燥，盐渍土壤中的保水作用。由于这项研究的局限性，需要进一步评估，以了解在具有不同生物群的不同土壤中使用木质素的水凝胶的效率。