فهرست نشریات علمی دسترسی آزاد ایران

To improve crop and soil productivity, residues of major agricultural and horticultural crops, namely grape waste, wheat straw, and brown walnut shell, were converted into biochars and applied to soil at a rate of 2% (w/w). The experimental treatments included control soil (CS), soil amended with grape waste biochar (GSB), soil amended with wheat straw biochar (WSB), and soil amended with brown walnut shell biochar (NSB). Both biochar-amended and non-amended soils were used for wheat cultivation under pot conditions. Soil enzyme activities, were measured. In addition, soil parameters and plant parameters were evaluated. The results showed that application of GSB significantly increased soil ammonium, nitrate, available phosphorus, and organic carbon concentrations compared with the control treatment. Nitrate concentration increased during wheat growth, whereas ammonium, available phosphorus, and organic carbon concentrations decreased over time. Biochar application increased the activities of all enzymes except phosphatases. Invertase activity in the GSB and WSB treatments increased significantly compared with the control. The addition of GSB increased urease activity by 1.4-fold relative to the control treatment. The geometric mean of enzyme activity (GMEa) was higher in the GSB and WSB treatments than in the other treatments. Based on biochar effects, the percentage of enzyme change (Rch) followed the order GSB > WSB > NSB. The lowest enzyme resistance index was observed in the GSB treatment, whereas the highest was recorded in the NSB treatment. All biochar-amended soils exhibited higher thousand-grain weight and wheat grain yield compared with the control.