Facile Access to Gleditsia microphylla Galactomannan Hydrogel with Rapid Self-Repair Capacity and Multicyclic Water-Retaining Performance of Sandy Soil

Sandy soil has poor water-holding performance, making it difficult for plants to survive, which worsens the deterioration of the ecological environment. Therefore, borax cross-linked Gleditsia microphylla galactomannan hydrogel (GMGH) was prepared, and its practicability as a water-retaining agent was analyzed. GMGH exhibited fast self-healing performance (150 s, approximate to 100%) and a high swelling index (88.70 g/g in pH 9). The feasibility of improving the water absorption and retention properties of sandy soil was explored by mixing different proportions (0.1, 0.3, 0.5 wt % sandy soil) of GMGH and sandy soil. The results showed that sandy soil had a more porous structure after adding 0.5 wt % GMGH, and its water absorption index increased from 15.68 to 38.12%. In an artificial climate box, the water-holding time of the sandy soil was extended from 3 to 23.5 days, and the cycles of water absorption and retention were more than 10 times. Therefore, GMGH has broad application prospects as a potential water-retaining agent for desertification control.

Automated summary

Sandy soil has poor water-holding capacity, leading to difficulties for plant survival and exacerbating ecological degradation. The study developed borax cross-linked Gleditsia microphylla galactomannan hydrogel (GMGH) as a water-retaining agent, which demonstrated fast self-healing capability and high swelling index. Mixing GMGH with sandy soil improved its water absorption and retention properties, with increased porous structure and prolonged water-holding time. GMGH shows promising application prospects in desertification control.