Agronomy, Journal Year: 2025, Volume and Issue: 15(3), P. 724 - 724

Published: March 17, 2025

The degradation of black soil cropland has occurred to varying degrees in the northern agropastoral ecotone. Crop–forage rotation is an effective way improve quality, with Medicago being preferred perennial legume. C, N, and P stoichiometric ratios are key indicators quality organic matter composition, reflecting status internal cycles soil. This study aims investigate ecological grassland soils different planting durations, explore regulatory effects nitrogen fertilizer on carbon (SOC), total (TN), phosphorus (TP) content, assess impacts these changes ecosystem. was conducted long-term cultivated core experimental platform Hulunber National Field Station. Based forage yield nutrient measurements, field-based observations laboratory analyses were carried out. × varia subject, treatments: CK (0 kg N ha−1), N75 (75 N150 (150 ha−1). A randomized block design adopted. Variance analysis, boxplot statistics, scatterplot fitting methods used examine properties application stoichiometry established grasslands. results indicate that, based growth characteristics alfalfa, dynamics, its effectiveness improving optimal period for alfalfa ecotone 4–5 years, but it can also be shortened 3 years. Soil carbon, nitrogen, contents significantly influenced by duration. As years increase, first increase then decrease, while content initially decreases followed a slight increase. pH gradually rises both depth. Both low high levels reduce concentration (by 0.40% 10.14%, respectively). Low increases 1.50%), whereas 7.6%). 36.67% 35.26%, For from planted 8 carbon-to-nitrogen ratio ranges 9.08 9.76, carbon-to-phosphorus 13.00 151.32, nitrogen-to-phosphorus 1.65 17.14. In summary, primarily rate, duration, ratios, pH. Nitrogen positive effect ratios. annual reach 8.94 10.07 tons per hectare., remains limiting factor. These findings provide crucial data understanding impact crop–forage cycles, as well land use improvement.

Language: Английский