The application of animal manure combined with straw is an important strategy for sustainable agricultural production. The objective of this study was to investigate the effects of animal manure combined with straw on soil enzymes and microbial quantity. The two-year experiment involved four...

Straw mulching (SM) is recognized as an effective management practice to alter soil nutrient translocation on the gentle slope arable land. The objective of this work was to evaluate the effects of straw mulching on soil nutrient content and microbial community. The two-year experiment involved six treatments: experiment slopes (3, 6, and 9°, 20 m long) and mulching (i.e. only maize straw (1.65 kg m⁻²) was mulched, and no mulch). Straw mulching treatments increased the levels of soil available nitrogen (AN), total nitrogen (TN), available phosphorus (AP), and total phosphorus (TP) at three different soil slopes. The AN content for 9° slopes straw mulching (NS) was 69.4% higher than 9° slopes no straw mulching (N), and also enhanced bacterial richness and diversity. The relative abundance of Proteobacteria and Bacteroidetes for NS were 48.3% and 76.7% larger than N treatment, respectively. Ascomycota was higher in 6° slopes straw mulching (55.3%) followed by NS (53.5%). In all, our findings showed that the application of straw mulching was a better approach for the restoration of slopy arable land (especially in arable land with high slope) fertility based on enhancing soil nutrient and microbial community.

Organic waste has been found to alter soil fertility and influence crop yield and is a key management strategy for achieving sustainable agriculture. We studied the change in the soil properties, enzymes, microbial community composition, and crop yields across four organic waste return practices (CK: no maize straw and no animal manure control; MS: maize straw only; CS: chicken manure plus maize straw; OS: ox manure plus maize straw) in a Mollisol. Our analysis showed that the total nitrogen, total phosphorus, available phosphorus, and soil organic carbon contents increased by 2.52-6.64%, 7.22-21.67%, 9.92-25.61%, and 9.56-29.98% under the organic waste return treatments, respectively, compared to the CK. Chicken manure plus maize straw treatment enhanced the activities of soil urease and alkaline phosphatase, and also recorded the highest maize yield. Additionally, the application of animal manure and maize straw increased the bacterial and fungal diversity indexes and the abundance of Pseudomonadota, Ascomycota, and Basidiomycota. In conclusion, our findings revealed that applying organic waste, especially chicken manure plus maize straw return, was the most effective treatment for enhancing soil factors, microbial community, and maize yields. These findings offer valuable insights for the development of more effective organic waste return strategies.

The processes of soil aggregates formation and stabilization play a crucial role in determining the sequestration of soil organic carbon (SOC), and organic wastes (OW) amendment is an effective measure for achieving more sustainable agriculture. However, the changes in soil aggregates and SOC in response to straw combined with differential animal manure remain elusive. Herein, this study investigated the effects of the four treatments (CK—no organic wastes; MS—maize straw only; OS—ox manure plus maize straw; CS— chicken manure plus maize straw) on soil aggregates and SOC of different sizes at different soil depths. Compared with the CK, the macroaggregates (SMAs) contents corresponding to CS-, OS-, and MS-treated soils were 15, 12, 2% at the 0–10 cm soil depth. In the 10–20 cm soil layer, the MWD and GWD in CS treatment were higher than that of CK. Moreover, OW treatments provide better accumulation of the SOC contents in megaaggregates (LMAs) and SMAs. The contribution rate of SOC of LMAs and SMAs aggregates in CS and OS increased than in the MS and CK. This indicated that manure and straw (especially maize straw plus chicken manure) help to sustain the stability of soil aggregates and SOC sequestration.