Aerobic rice is gaining global recognition for its role in the conservation of water. However, its productivity is often constrained by several deficiencies in the soil-plant system. Particularly, in absence of flood-induced phosphorus (P) desorption, it is likely that P availability in aerobic soils would be reduced thus affecting the productivity. Presently, our understanding of soil P dynamics and its bioavailability in aerobic rice-based system(s) is limited, particularly in alkaline soils. In this study, the impact of sole fertilizer and integrated P management on soil P dynamics, biochemical and biophysical properties and crop yields in direct-seeded rice (DSR)-lentil rotation in alkaline soil was assessed to devise sustainable management option(s). Seven different P treatments in aerobic direct seeded rice-lentil system [subscript value (kg P ha⁻¹)] i.e., P control (P_[0−0]), three sole fertilizer-P treatments with variable rate application to component crops (P_[22−22], P_[33−11], P_[11−33]), and three integrated treatments ([P₁₁₋₁₁+ phosphate solubilizing bacteria (B)], [P_16.5−5.5+ rice residue recycling (RR)+B], [P_5.5−16.5+lentil residue recycling (LR)+B]) in aerobic direct seeded rice-lentil system along with a conventional flooded rice-lentil system with the recommended fertilizer-P rate (P_[22−22]FR) were studied. Given the recommended sole fertilizer-P rate, the aerobic rice soil (P_[22−22]) had lower available-P (8–10 %) compared to the flooded rice soil (P_[22−22]FR). The rice residue recycling integrated treatment (P_16.5−5.5+RR + B) increased soil available-P in both the rice (5–6 %) and lentil (12–13 %) crop season over the recommended sole fertilizer-P treatment (P_[22−22]), and also increased the system productivity by 6–7 %. The higher NaHCO₃-Pi (13 %) and dissolved non-reactive P (DNRP) (7%) in the treatment P_16.5−5.5+RR + B over the treatment P_[22−22] suggested a higher soil P mobilization potential of rice residue recycling integrated treatment. The effect of lentil residue recycling integrated treatment (P_5.5−16.5+LR + B) and recommended sole fertilizer-P treatment P_[22−22] was similar on soil P and crop yields, and would thus be an option when considering the reduction of P fertilizer use in aerobic rice. Soil aggregation, very-labile carbon, microbial biomass carbon, DNRP exhibited positive correlations with P bioavailability in the aerobic rice soil. Our results suggested that C-stabilization in aerobic rice soil is altered with P input, the lowest rate being recorded in the control treatment. Hence, the study concluded that reduced soil P availability could limit the productivity potential of aerobic rice-lentil system in alkaline soils, and integrated treatments involving in-situ crop residue recycling (rice in particular) and suboptimal fertilizer rate could improve soil P bioavailability, soil quality parameters, and crop yields, thus, recommended for sustainable management.

好氧水稻因其在节约用水方面的作用而获得全球认可。然而，它的生产力常常受到土壤-植物系统中的几个缺陷的限制。特别是，在没有洪水引起的磷（P）解吸的情况下，好氧土壤中磷的有效性很可能会降低，从而影响生产力。目前，我们对有氧水稻系统中土壤磷动态及其生物有效性的了解有限，特别是在碱性土壤中。在这项研究中，评估了单一施肥和综合磷管理对碱性土壤中直播稻 (DSR)-扁豆轮作中土壤磷动态、生化和生物物理特性以及作物产量的影响，以制定可持续管理方案。^-1 )]即磷控制 (P _[0-0] )，三种单一施肥-磷处理，对组分作物进行可变施用量施用 (P _[22-22] , P _[33-11] , P _{[11-33 ] ]} )，以及三个综合处理（[P ₁₁₋₁₁ + 溶磷菌（B）]、[P _16.5−5.5 + 稻渣回收利用（RR）+B]、[P _5.5−16.5 +扁豆渣回收利用（LR） +B]) 在有氧直播水稻-扁豆系统中以及具有推荐肥料-P 比率 (P _[22−22]FR )的常规淹水水稻-扁豆系统中进行了研究。给定推荐的唯一肥料-P 用量，好氧水稻土 (P _[22−22]) 与淹水水稻土壤 (P _[22−22]FR )相比具有较低的有效磷 (8–10% )。与推荐的单一施磷处理相比，稻渣回收综合处理 (P _16.5−5.5 +RR + B) 增加了水稻 (5-6 %) 和小扁豆 (12-13 %) 作物季节的土壤有效磷（ P _[22−22] )，并且还将系统生产率提高了 6–7%。处理 P _16.5−5.5 +RR + B 中较高的 NaHCO ₃ -Pi (13 %) 和溶解的非反应性 P (DNRP) (7%)高于处理 P _[22−22]表明更高的土壤 P 动员潜力稻渣资源化综合处理。扁豆渣回收综合处理效果(P _5.5-16.5+LR + B) 和推荐的单施磷处理 P _[22−22]对土壤磷和作物产量的影响相似，因此在考虑减少需氧水稻中磷肥的使用时是一个选择。土壤团聚体、极不稳定碳、微生物生物量碳、DNRP 与好氧水稻土壤中磷的生物有效性呈正相关。我们的结果表明，好氧水稻土壤中的 C 稳定性随 P 输入而改变，在对照处理中记录的速率最低。因此，该研究得出的结论是，土壤磷的有效性降低可能会限制碱性土壤中好氧水稻 - 扁豆系统的生产力潜力，以及涉及原位的综合处理 作物残留物回收（特别是水稻）和次优施肥率可以提高土壤磷的生物有效性、土壤质量参数和作物产量，因此建议用于可持续管理。