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Continuous monitoring of soil quality is vital to understand the effects and to identify best management practices for sustainable agroecosystems. This study focuses on evaluating the soil quality and crop yield sustainability in a long-term maize-wheat cropping system experiment spanning 47 years. Physical, chemical, and biological soil quality indicators were assessed at two soil depths (0–0.15 m and 0.15–0.30 m) under eleven fertilizer and amendment regimes i.e., 50 % NPK, 100 % NPK, 150 % NPK, 100 % NPK + Zn, 100 % NPK+ hand weeding, 100 % NP, 100 % N, 100 % NPK + farmyard manure (FYM), 100 % NPK(S), 100 % NPK + lime and control, laid out in a completely randomized block design. Principal component analysis (PCA) was employed to select a minimum data set (MDS) of indicators for soil quality assessment, followed by weighted additive approach to calculate the soil quality index (SQI). Results showed that balanced dose of NPK fertilizers, in combination with FYM or lime, enhanced average wheat grain yield by 39.9 and 29.4 % over sole 100 % NPK fertilizers, respectively. Treatment 100 % NPK + FYM recorded a significant improvement in aggregate stability, available nutrients, microbial biomass over control and 100 % NPK. The highest value of SQI (0–0.15 m) was recorded in 100 % NPK + FYM (0.99), followed by 100 % NPK + lime (0.86) and lowest in 100 % N (0.41). Omission of NPK, PK, K and S from fertilizer regime caused a decline of respective 33, 39, 22 and 6 % in the SQI, whereas, all the treatments recorded a decline in SQI in sub-surface layer. The average contribution of MDS towards the SQI of 0–0.15 and 0.15–0.30 m depth was labile carbon (LC) (30 %) > microbial biomass N (MBN) (28 %) > mean weight diameter (MWD) (17 %) > pH (16 %) > available K (6 %) and LC (33 %) > N mineralization (24 %) > MWD (22 %) > pH (21 %), respectively. The SQI positively correlated with average grain yield and SYI, highlighting the importance of soil quality for sustainable crop production. This research underscores the significance of continuous soil quality monitoring and use of balanced fertilization, organic manure and lime in maintaining soil health and crop productivity in agroecosystems. • Balanced NPK fertilizers with FYM or lime increased the wheat yield by 39.9 and 29.4 %, respectively. • Continuous urea application rendered the soil unproductive. • Labile carbon was the major contributor towards the soil quality index. • Soil quality index correlated positively with grain yield and sustainable yield index. [ABSTRACT FROM AUTHOR]

Liming materials are widely applied to alleviate soil acidification and increase rice yield in acidic soils, but their effects on nitrogen (N) use efficiency are still unclear. Here, we conducted a field-, pot-, and micro-plot experiment to investigate how the application of slaked lime (i.e., Ca(OH) 2) affects the fate of chemical fertilizer-N and straw-N in a double rice cropping system. In the field experiment, liming increased grain yield and N uptake by an average of 9.0% and 10.6%, respectively. In contrast, CaCl 2 application did not affect rice yield and N uptake, suggesting that the effects of lime application were not related to the addition of Ca2+. Results from a 15N tracer experiment (i.e., 15N-labeled urea and straw) indicated that liming reduced N uptake from fertilizer (−5.7%), but increased N uptake from straw (+31.3%). Liming also reduced soil retention of both urea- and straw-N and increased their loss rates. Taken together, our results indicate that although liming increases rice yield and N uptake, it lowers the use efficiency of fertilizer N and facilitates N losses. In addition, our results emphasize the need for long-term studies on the impact of liming on soil N dynamics in paddy soils. • Liming of an acidic rice paddy soil increased both rice yield and N uptake. • Addition of Ca2+ did not affect rice yield and N uptake. • Liming reduced N uptake from fertilizer but increased that from straw. • Liming reduced soil retention of both urea- and straw-N and increased their loss rates. [ABSTRACT FROM AUTHOR]