Effects of slag and biochar amendments on microorganisms and fractions of soil organic carbon during flooding in a paddy field after two years in southeastern China.

Incorporating amendments of industrial waste such as biochar and steel slag in cropland has been used to enhance the storage of soil organic carbon (SOC) while sustaining crop production. Short-term laboratory and field studies have identified important influences of biochar on active SOC fractions associated with soil microbial activity in paddy soils, but the long-term effects remain poorly understood. To address these knowledge gaps, we examined the effects of slag, biochar, and slag+biochar treatments on total SOC concentration, active SOC fractions and soil microbial communities in a paddy field two years after incorporation.

Steel slag and biochar amendments decreased CO emissions by altering soil chemical properties and bacterial community structure over two-year in a subtropical paddy field.

Waste amendments, such as steel slag and biochar, have been reported as a strategy for improving soil fertility, crop productivity, and carbon (C) sequestration in agricultural lands. However, information regarding the subsequent effects of steel slag and biochar on C cycling and the underlying microbial mechanisms in paddy soils remains limited. Hence, this study aimed to examine the effect of these waste amendments (applied in 2015-2017) on total soil CO emissions, total and active soil organic C (SOC) contents, and microbial communities in the early and late seasons in a subtropical paddy field.

[Subsequent Effects of Slag and Biochar Application on Greenhouse Gas Emissions from Paddy Fields in the Fuzhou Plain].

We investigate whether slag and biochar applications have subsequent effects on greenhouse gas emissions from paddy fields by applying biochar (B), slag (S), and a biochar-slag mix (BS) to paddy fields in the Fuzhou Plain, China. Applications of the three treatments along with a control (CK) of no amendment were made in 2015 before early and late rice seedlings were transplanted. Two years later in 2017, the CO, CH, and NO emissions in the different treatments and control were measured in the early and late rice growing seasons.

Coupled steel slag and biochar amendment correlated with higher methanotrophic abundance and lower CH emission in subtropical paddies.

Aerobic methanotrophs in paddies serve as methane (CH) filters and thereby reduce CH emissions. Amending soil with waste products can mitigate CH emissions in crops, but little is known about the impacts of amendments with steel slag and biochar on the populations and activities of aerobic methanotrophs in rice cropland. We used real-time quantitative PCR detecting system and high-throughput sequencing to determine the effects of slag and biochar amendments on CH emission, abundance, and community structure of methanotrophs, and the relationships between soil properties and the abundance and community composition of methanotrophs during the rice growing season in both early and late paddies.