High Level of Iron Inhibited Maize Straw Decomposition by Suppressing Microbial Communities and Enzyme Activities

Abstract

In order to study the linkages between the crop straw decomposition rate and the change in soil biological properties after the straw returned to the soil with different iron (Fe2+) contents, a 180-day incubation experiment was performed to examine the decomposition of maize straw (MS) under three Fe2+ levels, i.e., 0, 0.3, and 1 mg g−1. Enzyme activities regarding straw decomposition and microbial communities under 0 and 1 mg g−1 Fe addition were also detected. The results showed that Fe2+ addition significantly inhibited MS decomposition. This was evidenced by the higher contents of hemicellulose, cellulose, and lignin in Fe2+ treatments on day 180. High-Fe addition (1 mg g−1) decreased the activity of Laccase (Lac) by 71.82% compared with control on day 30. Furthermore, the principal coordinates analysis (PCoA) indicated that high-Fe mainly affected the bacterial community. In particular, it suppressed the relative abundance of Microbacteriaceae in phylum Actinomycota that, in turn, is a potential decomposer of crop straw by secreting lignocellulolytic enzymes. A high level of Fe2+ inhibited the decomposition of hemicellulose, cellulose, and lignin in MS by reducing the relative abundance of phylum Actinobacteria in bacteria and suppressing Lac activity. Our findings provide guidance for returning crop straws in soils with high-Fe content.

Technologies for Environmental Ecological Restoration and Agricultural Sustainability Are the Focus of Future Safeguarded Agriculture Development

“…of oil absorption using the one-factor-at-a-time (OFAT) and response surface methodology (RSM) approaches. The study found that under the conditions of 128 °C temperature and 36 (v/v)% oil concentration, CG demonstrated an efficiency of 93.54% in absorbing 22.45 mL of oil, while keeping the packing density and time constant at 30 min and 0.20 g/cm 3 , respectively. Compared to other natural sorbents, CG's oil/water selectivity properties make it a cost-effective method with high potential for combating oil spills.…”

“…[2]. (B) Redundancy analysis depicting the relationship between the bacterial phyla and enzyme activities [3]. (C) Structural equation modeling (SEM) of the effects of submergence on organic carbon pool as a result of submergence-induced changes in soil acidification and soil environment [4].…”

“…Jin et al (2022) investigated the relationship between crop straw decomposition rate and changes in soil biological properties after straw return in soils with different iron (Fe 2+ ) contents through a 180-day incubation experiment (Figure 1B) [3]. The results demonstrated that the addition of Fe 2+ significantly inhibited the decomposition of maize straw (MS).…”

“…(A)Effects of SDMI application on soil total N (a), available N (b), total P (c), available P (d), total K (e), and available K (f) under different agricultural management practices, expressed as the mean effect size with bootstrapped 95% confidence intervals[2]. (B) Redundancy analysis depicting the relationship between the bacterial phyla and enzyme activities[3]. (C) Structural equation modeling (SEM) of the effects of submergence on organic carbon pool as a result of submergence-induced changes in soil acidification and soil environment[4].…”

Emerging technologies of employing algae and microorganisms to promote the return-to-field of crop straws: A mini-review

“…Frontiers in Bioengineering and Biotechnology frontiersin.org 4 Application of microorganisms based fermentation to pretreat crop straw 4.1 Decomposition process of crop straw Zhang et al (2014) analyzed 784 crop straw samples, including cotton stalk samples, wheat straw, rape stalk, rice straw, and corn stover, collected from different regions of China, discovering that crop straw contains some essential elements, including carbon, nitrogen, sulfur, phosphorus, and potassium (Zhang et al, 2014;Wang et al, 2020). It was observed that in nature, crop straw can be decomposed gradually by bacteria, fungi, and other microbes with the assistance of hemicellulase, cellulase and ligninase (Henriksen and Breland, 2002;Jin et al, 2022). For example, Ji et al (2018) reported that Methanosarcina and Methanothrix as well as hydrogentrophic Methanocella could be regarded as the important archaeal taxa involved in rice straw degradation (Ji et al, 2018).…”