Biological transfer of dietary cadmium in relation to nitrogen transfer and 15N fractionation in a soil collembolan-predatory mite food chain

Abstract

a b s t r a c tEffects of cadmium (Cd) on collembolans and predatory mites have been well studied but Cd accumulation and biological transfer and the relationship between Cd trophic transfer and nitrogen (N) isotope fractionation and transfer in soil micro-arthropod food chains remain poorly understood. Here, we investigated the biological transfer and trophic toxicity of Cd and the effects of dietary Cd exposure on 15 N fractionation in animal tissues and N transfer from food in a soil collembolan (Folsomia candida)-predatory mite (Hypoaspis aculeifer) food chain using experiments conducted in plate and soil systems. Synchronized F. candida were fed yeast or wheat spiked with 0 (Control), 50 (Cd50), 100 (Cd100) or 200 (Cd200) mg Cd g À1 food for two weeks and were then offered to synchronized H. aculeifer as prey for two weeks. Cadmium concentrations in tissues of both the collembolan and its predator increased as the Cd concentrations in the food yeast or wheat increased in both the plate and soil systems, and the Cd concentrations in the food and the animals were all significantly and positively correlated. Except for the controls, the Cd bioaccumulation factor (BAF) between adults of predatory mites and consumer collembolans (0.20e1.13) was 2.5e14 times higher than that from food yeast/wheat to consumer collembolans (0.02e0.08). Cadmium transfer has not altered the reproduction of the filial generation collembolans but the reproduction of the predatory mite declined by 34.3% with the Cd concentration in its juveniles reaching 5.94 mg g N isotope application may be limited in Cd polluted soil ecosystems, and the N transfer function of soil food webs may be more vulnerable in polluted ecosystems.

Ecotoxicity of cadmium in a soil collembolan-predatory mite food chain: Can we use the 15N labeled litter addition method to assess soil functional change?

“…The procedures for culturing and synchronizing animals are consistent with the methods of Zhu et al (2016a). The ages of F. candida and H. aculeifer were 10e12 and 32e35 days, respectively, in our tests.…”

Insights into the Role of the Fungal Community in Variations of the Antibiotic Resistome in the Soil Collembolan Gut Microbiome

“…The synchronization and culturing processes that were used for F. candida are described in our previous studies. , The fertilizers were applied to soil dominated by a total nitrogen content of 12.6 g N/m 2 , which is commonly used in local agricultural practice. Before introducing collembolans, the soil moisture was adjusted to 75% of the field water capacity and preincubated for 2 weeks.…”

Biological transfer of silver under silver nanoparticle exposure and nitrogen transfer via a collembolan-predatory mite food-chain and ecotoxicity of silver sulfide

“…These two animal groups are prevalent in soils and several species have been adopted as standard animals for singlespecies ecotoxicological tests (Fountain and Hopkin, 2005;Huguier et al, 2015). Zhu et al (2016) established a soil animal food chain comprising Hypoaspis aculeifer and Folsomia candida to study the influence of Cd at different trophic levels and its effects on nutrient element transfer. This food chain has been used in ecotoxicological studies of pollutants within trophic levels and the pollution effects on the functioning of soil ecosystems (Zhu et al, 2018).…”