Dynamics of soil bacteria and fungi communities of dry land for 8 years with soil conservation management.

Microorganisms play an important role in nutrient cycling and ecosystem stability. This experiment studied the conservation management approaches [control without fertilizer (CK); fertilizer and different mulching based straw mulching (SM), plastic mulching (PM), ridge-furrow with plastic mulching (RFPFM), and green manure (GM)] effects on the soil microbial community structures in spring corn (Zea Mayis) dry land. The results showed that the bacterial phylum mainly included Proteobacteria (28.2%-36.8%), Acidobacteriota (9.1%-17.9%), Bacteroidota (5.6%-8.9%) and Actinobacteria (3.1-6.2%). The most richness fungal components were Ascomycota (35.2%-44.2%), Basidiomycota (3.3%-12%) and Mortierellomycota (3.4%-6.6%). Additionally, the highest Chao1 and abundance-based coverage estimator (ACE) indexes of bacteria (2931.9 and 2953.7) and fungi (1083.316 and 1100.650) were present in RFPFM that indicating the richest microbial abundance, the highest Shannon and Simpson indexes was exist in PM (9.332 and 0.996) for bacteria and RFPFM (6.753 and 0.974) for fungi. Therefore, this study reveals the conservation management of fertilizer addition and mulching management obviously promoted microbial diversity and altered the superior microbial distribution that provides a potential way for agricultural sustainable management approaches in production practice during circular economy.

[Effects of reducing N, straw returning and dicyandiamide application on winter wheat yield and nitrogen budgets in rain-fed region.] / 减氮-ç§¸ç§†è¿˜ç”°åŠåŒæ°°èƒºæ–½ç”¨å¯¹æ—±åœ°é›¨å »åŒºå†¬å°éº¦äº§é‡å’Œæ°®å¹³è¡¡çš„å½±å“.

In a 3-year field experiment, effects of reducing N fertilizer, straw returning and dicyandiamide (DCD) application on wheat yield and nitrogen budgets under wheat-fallow system were studied in rain-fed region. The experiment was carried out in Yangling of Shaanxi Province, and 4 treatments were installed including no nitrogen (CK), 220 kg N·hm-2 and no straw returning (FP), 150 kg N·hm-2 and straw returning (OPT), 150 kg N·hm-2, 7.5 kg·hm-2 DCD and straw returning (OPT+DCD). The results showed there was no remarkable difference for wheat yield between OPT and FP, but the N use efficiency of the former was 6.1% more than that of the latter, and the apparent N loss ratio was 7.2% less. OPT+DCD increased the average yield of winter wheat by 10.4% and 7.9% respectively compared to OPT and FP, the N use efficiency of winter wheat increased by 20.8% and 28.1%, and the apparent N loss ratio decreased by 8.5% and 15.1%, respectively. NH4+-N content in 0-20 cm of soil increased, accordingly the NO3--N content decreased in 40 to 45 days when DCD was applied.