Alfalfa cropping is superior to cotton and rapeseed cropping in improving the quality and microbial diversity of reclaimed saline soils

ABSTRACT

Soil salinisation has led to increasing abandonment of farmlands in the arid region of northwest China, and the cultivation of cash crops has become an important way to reuse abandoned farmlands and remediate saline soils. In this study, the effects of cotton (Cot), alfalfa (Alf), and rapeseed (Rap) cropping on the bacterial and fungal communities in saline soil were compared based on high-throughput sequencing. The results showed that soil pH and electrical conductivity (EC) of the Cot, Alf, and Rap groups decreased significantly compared with those of bare land (CK). Especially, soil pH (8.3) and EC (0.93 mS cm^-1) of the Alf group decreased the most, and the contents of total nitrogen (TN) and total phosphorus (TP) increased the most, which increased by 250% and 91.4%, respectively compared with those of the CK (p < 0.05). Actinobacteriota and Proteobacteria were the dominant bacterial phyla in the three groups, Ascomycota and Basidiomycota were the dominant fungal phyla. The diversity of soil bacterial and fungal communities in the Alf group was higher than that in the Cot and Rap groups. The results of RDA and PERMANOVA analysis showed that soil pH, EC, C/N ratio, and TN were the main factors affecting soil bacterial and fungal communities in the three groups. In general, Cot, Alf, and Rap cropping all could reduce soil pH and EC and improve soil microbial community structure and diversity, but Alf cropping had the best effects in improving saline soil quality and bacterial and fungal diversity.

KEYWORDS:

• Alfalfa
• ecological restoration
• bacteria
• fungi
• saline soil

Acknowledgements

This research was financially supported by the High-level Talents Research Start-up Project of Shihezi University (grant number: RCZK201928).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the High-level Talents Research Start-up Project of Shihezi University [grant number RCZK201928].

Notes on contributors

Fating Yin

Fating Yin, a PhD graduate from the Agricultural College at Shihezi University, is currently a researcher with Laboratory of Resources and Environmental Carrying Capacity of the Yellow River Basin at Zaozhuang University. His research interests include remediation of saline soils, crop cultivation, and soil microorganisms.

Lei Yang

Lei Yang is a researcher with Key Laboratory of Oasis Eco-agriculture of Xinjiang Production and Construction Corps and currently a doctoral candidate at the Agricultural College of Shihezi University. His research interests include crop cultivation, straw incorporation, and soil microorganisms.

Wei Pang

Wei Pang, a PhD graduate from the Agricultural College at Shihezi University, is currently a researcher with Key Laboratory of Oasis Eco-agriculture of Xinjiang Production and Construction Corps. His research interests include remediation of saline soils, crop cultivation, and soil microorganisms.