نقش نماتد Caenorhabditis elegans Maupas, 1900 (Nematoda: Rhabditida) در تعیین شاخص‌های آلودگی زیست محیطی

The demand for resources, especially food, increases with population growth. To respond to the increasing demand for food, soil health is threatened by improper soil management practices such as plowing, excessive use of chemical fertilizers and pesticides. Therefore, soils will be increasingly exposed to degradation, pollution, physicochemical properties deterioration, biological diversity reduction and low productivity. One of the most important criteria for sustainable agricultural development is maintaining the health and functional capacity of the soil as a dynamic system, with the aim of maintaining biodiversity, water and air quality, and improving the health of plants, animals and humans. Assessment of soil health depends on its physical, chemical and biological indicators. Biological indicators include the microbial and macroscopic part. Nematodes are the most abundant and diverse animals and their sensitivity to pollutants and environmental changes is different. Nematode communities, as one of the most important soil biomarkers, reflect the state of soil health with changes in indicators such as abundance, diversity, population changes, and biological effects. Both free-living and plant parasitic nematodes are effective ecological markers that play an important role as consumers at different levels of the food chain of aquatic and terrestrial ecosystems by influencing the food cycle. Agricultural operations, tillage, improper management of soil nutrition affect the population of soil nematodes. Therefore, any change in nematode communities is considered a warning to threaten soil health. By affecting the environment and soil organisms and plant growth, soil nematodes also play a role in the food cycle, energy transfer and global soil carbon cycle. Some free-living nematodes such as Caenorhabditis elegans are used as biological models to evaluate soil health status. The important advantages of this species are its short lifespan, simple and cheap propagation, availability of complete genome sequence and access to many genetically modified isolates, quick response to environmental changes, especially chemical toxins and soil pollutants. Physical, chemical and biological factors affect the growth, reproduction and movement of C. elegans. In this review, more types of bioassays to evaluate the environmental toxicity of soil will be discussed. The use of the C. elegans model to address agricultural and ecological issues is at the beginning. Analysis of nematode population fluctuations provides a potential tool for soil food web management. In this study, the responses of C. elegans to soil chemical pollution in the studies that have been done so far are compiled and presented.