Dynamics of ammonia oxidizers and denitrifiers in response to compost addition in black soil, Northeast China

Abstract

Organic fertilizer application could have an impact on the nitrogen cycle mediated by microorganisms in arable soils. However, the dynamics of soil ammonia oxidizers and denitrifiers in response to compost addition are less understood. In this study, we examined the effect of four compost application rates (0, 11.25, 22.5 and 45 t/ha) on soil ammonia oxidizers and denitrifiers at soybean seedling, flowering and mature stage in a field experiment in Northeast China. As revealed by quantitative PCR, compost addition significantly enhanced the abundance of ammonia oxidizing bacteria (AOB) at seedling stage, while the abundance of ammonia oxidizing archaea was unaffected across the growing season. The abundance of genes involved in denitrification (nirS, nirK and nosZ) were generally increased along with compost rate at seedling and flowering stages, but not in mature stage. The non-metric multidimensional scaling analysis revealed that moderate and high level of compost addition consistently induced shift in AOB and nirS containing denitrifers community composition across the growing season. Among AOB lineages, Nitrosospira cluster 3a gradually decreased along with the compost rate across the growing season, while Nitrosomonas exhibited an opposite trend. Network analysis indicated that the complexity of AOB and nirS containing denitrifiers network gradually increased along with the compost rate. Our findings highlighted the positive effect of compost addition on the abundance of ammonia oxidizers and denitrifiers and emphasized that compost addition play crucial roles in shaping their community compositions and co-occurrence networks in black soil of Northeast China.

Studying Microbial Communities through Co-Occurrence Network Analyses during Processes of Waste Treatment and in Organically Amended Soils: A Review

“…In this regard, the application of compost amendments into soil has been shown to increase network complexity for both bacteria and fungi when compared to inorganic fertilization and/or unamended treatments [100][101][102][103]. A similar trend in co-occurrence networks has been reported for other types of amendments like manure and straw [104].…”

“…Particular emphasis has been placed on microbial groups that carry out key functions in the agroecosystems, namely, those affecting nitrogen turnover rates. Yang et al [100] observed that the complexity of both ammonia oxidizers and nirS containing denitrifiers networks gradually increased along with the compost rate. This is of particular importance for the productivity of plants given that nitrification and denitrification are among the most important soil N transformations.…”

Interactive impacts of boron and organic amendments in plant-soil microbial relationships

“…Thus, in the high-B treatment, the functionalities predicted from 16S rRNA gene sequencing (using FAPROTAX) indicated greater potential denitrification and lower potential nitrification and aerobic ammonia oxidation, together potentially resulting in high levels of NH4 + in soil. Other studies have shown that compost addition can increase the rate of denitrification relative to nitrification (Yang et al, 2020;Yin et al, 2019). This potential release of NH4 + in soil links with the known ability of these soluble chemical forms in soil to dissolve minerals, via chelation, and to promote their solubility in the soil solution and hence their acquisition by plants and microbes (Adeleke et al, 2017;Antoniadis and Alloway, 2002).…”

Soil Amendments Alter Ammonia-Oxidizing Archaea and Bacteria Communities in Rain-Fed Maize Field in Semi-Arid Loess Plateau

“…After that, we built a neighbor-joining tree using a Kimura 2-parameter distance with 1000 bootstrap replicates in MEGA 6 [41] to classify AOA-AOB OTUs. We used the nomenclature for AOA-amoA clusters as defined by [42] and the nomenclature for AOB-amoA as defined by [23]. The sequences of AOA-amoA and AOB-amoA were deposited in the NCBI database (Accession number: PRJNA723364 and PRJNA722852).…”

“…More experimental evidence is needed, especially to confirm competitive interaction with keystone taxa in microbial networks. Some studies have been conducted to explore the effects of chemical and organic fertilizers on bacterial communities to discover taxonomic composition and phylogenetic diversity and its environmental drivers [1,8,23,24]. Though this knowledge is crucial in understanding soil microbial diversity, there is still the need to study the long-term effects of different fertilization regimes in the semi-arid Loess Plateau of northwestern China, where soil fertility loss and climate change are of major concern [25].…”