Objective The aims were to investigate the effects of soil contamination with sodium cyclamate on nematode community and to understand the response mechanisms of soil fauna under sweetener pollution.

Method In this study, soil nematodes were exposed to different concentrations of sodium cyclamate for 60 days to examine its potential impact on the soil nematode community structure (CP, 1-4). The treatment groups included CK (control), SC1 (1 mg kg⁻¹ sodium cyclamate), and SC10 (10 mg kg⁻¹ sodium cyclamate).

Result The addition of sodium cyclamate significantly reduced nematode abundance (P < 0.05). Different functional groups exhibited varying responses to sodium cyclamate stress: the abundance of the CP2 functional group in nematodes decreased significantly in both SC1 and SC10 treatments (P < 0.05), while the abundances of CP3 and CP4 functional groups decreased significantly only at the concentration of 10 mg kg⁻¹ (P < 0.05). The abundances of bacterivorous, fungivorous, and phytophagous trophic groups were also reduced under sodium cyclamate exposure. The soil microbial biomass carbon (MBC) and nitrogen (MBN) in the SC10 treatment group were significantly lower than those in the control group (P < 0.05).

Conclusion Soil nematode community abundance decreased significantly under sodium cyclamate pollution, and notable changes occurred in the functional groups of nematodes. This study provides a scientific basis for a comprehensive understanding of the environmental risks of sweetener pollution in soil ecosystems.