Abstract: A compound fertilizer was coated with an alginategrafted absorbant and a fertilizer loss control agent. Alginategrafted fertilizers A and B were prepared and used for investigation of their waterretaining, losscontrolling and growthpromoting effects. Results indicated that the rate of soil water retention was 89.00% and 70.33% when the soil was treated with alginategrafted fertilizers A and B, respectively, while the corresponding value for compound fertilizer was 61.17%. The results from leaching experiments indicated that, in comparison to compound fertilizer, losses of nitrogen, phosphate and potassium from alginategrafted fertilizers A and B were decreased by 22.49% and 21.22%, 14.71% and 12.22%, and 15.51% and 13.13%, respectively. Applications of alginategrafted fertilizers A and B respectively increased the fresh weight of lettuce by 26.14% and 20.06% in comparison to compound fertilizer. In addition, the alginategrafted fertilizers also showed an obvious promoting effect on root growth of maize. The above results suggest that alginategrafted fertilizers possess stronger abilities to retain water and fertilizer, and to promote plant growth than compound fertilizer, and can be widely used in agriculture production.

Key words: hydrological process, significance level, jump, hydrological variability, environmental change.