Effects of Tropical Typical Organic Materials on Soil Physicochemical Properties and Microbial Community Structure

Abstract

Background: Returning pineapple leaves (PAL), banana stems (BAS), coconut husks (CCH), and organic fertilizer (OF) to the field is an important method for soil improvement. However, the effects of these materials on the soil remain unclear. Methods: This study employed a nylon-bag experiment filled with the above-mentioned materials to investigate the impacts on soil physicochemical properties and microbial community structure. Results: The short term acidification caused by PAL was due to the significant increase in isobutyric, isovaleric, and hexanoic acids. PAL and BAS promoted the formation of >0.25 mm aggregates in the short term (90 days). C and N were most abundant in <0.053 mm and 0.053–0.25 mm soil aggregates, while 13C and 15N were mainly enriched in 0.25–2 mm and >2 mm soil aggregates. The dominant biomarkers in the soil treated with PAL were Koribacteraceae, Chrysozymaceae, Trimorphomycetaceae, and Tremellales. The main biomarkers of soil treated with BAS were Caulobacteraceae, Aspergillaceae, Onygenales, and Ceratostomataceae. The dominant biomakers in the soil treated with CCH and OF were richer than those in soil treated with PAL and BAS. Conclusions: The long term return effects of CCH and OF are better than those of PAL and BAS.