Abstract:

To explore the improvement effect of agricultural wastes on saline-alkali wasteland for scientific application, this study selected three agricultural wastes, namely furfural residue, vinegar residue and bacterial residue. Random large-area plot experiment was conducted by applying them to soda saline-alkali wasteland. The application effects of the three amendments were comprehensively evaluated by measuring the physical and chemical properties of the soil, the structural characteristics of soil bacterial communities, and the biomass of aboveground plants. The results showed that the application of furfural residue, vinegar residue and bacterial residue could increase soil water content, reduce soil compactness and soil bulk density. The order of improvement effect from best to good was vinegar residue > furfural residue > bacterial residue. Furfural residue could effectively reduce the soil to pH 7.86, reduce the exchangeable sodium percentage (ESP) to 3.58%, and increase the organic matter to 36.00 g/kg. In contrast, vinegar residue and bacterial residue increased the soil pH and the exchangeable sodium percentage (ESP), and reduced the soil organic matter content compared with the control. The application of the three amendments reduced the richness and diversity of soil bacteria, changed the composition of dominant bacterial phyla, increased the relative abundance of soil Pseudomonadota, but decreased that of soil Acidobacteriota. The application of furfural residue increased the dry matter content of Sesbania sesban to 13406.7 kg/hm². Comprehensively, the effect of furfural residue on improving saline-alkali wasteland was better than that of vinegar residue and bacterial residue.

Key words: agricultural wastes, saline-alkali wasteland, improvement effect, exchangeable sodium percentage, richness, diversity