Straw and biochar strongly affect functional diversity of microbial metabolism in paddy soils

TitleStraw and biochar strongly affect functional diversity of microbial metabolism in paddy soils
Publication TypeJournal Article
Year of Publication2019
AuthorsYuan HZ, Zhu ZK, Wei XM, Liu SL, Peng PQ, Gunina A, Shen JL, Kuzyakov Y, Ge TD, Wu JS, Wang JR
JournalJournal of Integrative Agriculture
Volume18
Pagination1474-1485
Date PublishedJul
Type of ArticleArticle
ISBN Number2095-3119
Accession NumberWOS:000474451900009
KeywordsAgriculture, biochar amendment, biomass, carbon metabolism, Carbon sequestration, Community structure, forest soils, level physiological profiles, Microbial functional diversity, microresp (tm), nitrogen, organic-matter, paddy sod, rhizosphere, rice, straw, use efficiency
Abstract

The application of straw and biochar is widely practiced for the improvement of soil fertility. However, its impact on microbial functional profiles, particularly with regard to paddy soils, is not well understood. The aim of this study was to investigate the diversity of microbial carbon use patterns in paddy soils amended with straw or straw-derived biochar in a 3-year field experiment in fallow soil and at various development stages of a rice crop (i.e., tillering and blooming). We applied the community level physiological profiling approach, with 15 substrates (sugars, carboxylic and amino acids, and phenolic acid). In general, straw application resulted in the greatest microbial functional diversity owing to the greater number of available C sources than in control or biochar plots. Biochar amendment promoted the use of alpha-ketoglutaric acid, the mineralization of which was higher than that of any other substrate. Principal component analyses indicated that microbial functional diversity in the biochar-amended soil was separated from those of the straw-amended and control soils. Redundancy analyses revealed that soil organic carbon content was the most important factor regulating the pattern of microbial carbon utilization. Rhizodeposition and nutrient uptake by rice plants modulated microbial functions in paddy soils and stimulated the microbial use of N-rich substances, such as amino acids. Thus, our results demonstrated that the functional diversity of microorganisms in organic amended paddy soils is affected by both physicochemical properties of amendment and plant growth stage.

Alternate JournalJ. Integr. Agric.