Effects of Long-Term Straw Returning and Nitrogen Fertilizer Reduction on Soil Microbial Diversity in Black Soil in Northeast China

Abstract

Returning straw to the field, coupled with fertilizer application, is an effective means to improve the fertility of black soil in Northeast China. Previous studies have mainly focused on the physical and chemical properties of soil structure and fertility. However, few efforts have been made to study the impact of straw returning on the microbial community of black soil in Northeast China. Here, we studied the typical northeast black soil in Heilongjiang Province to characterize the effects of long-term chemical fertilizer application and straw returning on its bacterial community structure. High-throughput sequencing was conducted to characterize the bacterial community of northeast black soil under different agricultural fertilization treatments, and the main factors affecting the bacterial community of northeast black soil were revealed through bioinformatic analyses. The results of high-throughput sequencing analyses demonstrated that the main bacterial phyla in the black soil in Northeast China were Actinomycetes, Proteobacteria, Acidobacteria, Chloroflexus, and Bacteroidetes. Long-term application of chemical fertilizers significantly increased the fertility and crop yield of black soil in Northeast China but led to significant changes in bacterial community structure and a significant decrease in diversity. Although straw returning improved soil fertility, it did not alleviate the adverse effects of the long-term application of chemical fertilizers on soil bacterial communities. Furthermore, our results demonstrated that changes in soil pH were the main factor leading to variations in soil bacterial communities. Returning straw to the field based on fertilizer application can improve black soil fertility in Northeast China but fails to alleviate the adverse effects of fertilizer-induced soil acidification on the composition and diversity of soil bacterial communities. This suggests that returning straw to the field may not have a significant beneficial impact on the microbial ecology of the black soil of Northeast China. Therefore, further research is needed to establish new straw return strategies to maximize agricultural yields while minimizing ecological impacts.

Synergistic Effects of Rice Straw Return and Nitrogen Fertilizer on Rhizosphere Bacterial Communities and Soil Fertility

“…The combination of straw return and nitrogen fertilizer can induce physicochemical changes in the soil, resulting in alterations in the composition of the bacterial community (Jiao et al, 2023). In the present study, we observed that straw return amendments significantly influenced soil properties, as shown in Table 1.…”

An optimal combined slow-release nitrogen fertilizer and urea can enhance the decomposition rate of straw and the yield of maize by improving soil bacterial community and structure under full straw returning system

“…The dominant soil phyla in this study consisted mainly of Proteobacteria, Actinobacteriota, Acidobacteriota, Chloroflexi, Gemmatimonadota, Firmicutes, Bacteroidota, and Myxococcota. Furthermore, these dominant phyla were frequently found in other types of agricultural fields ( Jiao et al, 2023 ; Khmelevtsova et al, 2023 ) and were considered the prevailing group in most agricultural soils ( Eo and Kim, 2022 ; Kodadinne-Narayana et al, 2022 ).…”

Long-Term Straw Incorporation under Controlled Irrigation Improves Soil Quality of Paddy Field and Rice Yield in Northeast China

“…Additionally, a considerable amount of straw has accumulated over the years of rice cultivation. Consequently, straw incorporation has become an optimal measure to improve soil quality [43,44]. Furthermore, the limited availability of irrigation resources in Plants 2024, 13, 1357 3 of 16 agriculture has expedited the promotion of local water-saving irrigation techniques [45].…”