Toxicology Centre, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5B3, Canada; Department of Soil Science, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5A8, Canada.
Toxicology Centre, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5B3, Canada; Department of Animal and Poultry Science, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5A8, Canada.
J Hazard Mater. 2021 May 5;409:124969. doi: 10.1016/j.jhazmat.2020.124969. Epub 2020 Dec 25.
This study investigated the influence of habitat quality (HQ) on the reproduction and bioenergetics (energy reserve and metabolic enzyme activities) of the oribatid mite, Oppia nitens, in response to cadmium (Cd). In the baseline toxicity test, Cd elevated the carbohydrate reserve of adult mites at intermediate Cd concentrations (88 and 175 mg Cd kg) but without a change in lipid and protein reserve across 0-700 mg Cd kg. The activities of glucose metabolism enzymes, glucose-6-phosphate dehydrogenase (G6PDH) and pyruvate kinase (PK) were inhibited in the mites at 700 mg Cd kg. Adult mites reared in high HQ soils had higher reproduction relative to mites from low HQ soils when exposed to Cd in OECD soil, but there was no difference in bioenergetics between mites from low and high HQ soils. Hence, HQ significantly (p = 0.024) influenced the reproduction of mites (i.e., juvenile production) irrespective of the Cd concentration in the OECD soil but did not significantly affect the bioenergetics of the mites. We suggest that habitat quality's effect could be more significant than metal concentration on the biological fitness (juvenile production) of O. nitens in metal-contaminated soils.
本研究调查了生境质量（HQ）对食真菌甲螨 Oppia nitens 繁殖和生物能量学（能量储备和代谢酶活性）的影响，以应对镉（Cd）的影响。在基线毒性测试中，Cd 在中等 Cd 浓度（88 和 175 mg Cd kg）下提高了成螨的碳水化合物储备，但在 0-700 mg Cd kg 范围内脂质和蛋白质储备没有变化。在 700 mg Cd kg 时，葡萄糖代谢酶葡萄糖-6-磷酸脱氢酶（G6PDH）和丙酮酸激酶（PK）的活性受到抑制。在 OECD 土壤中暴露于 Cd 时，在高 HQ 土壤中饲养的成年螨比在低 HQ 土壤中饲养的成年螨具有更高的繁殖力，但在低 HQ 和高 HQ 土壤中饲养的螨之间在生物能量学方面没有差异。因此，HQ 显著（p = 0.024）影响了螨的繁殖（即幼体产量），而与 OECD 土壤中的 Cd 浓度无关，但对螨的生物能量学没有显著影响。我们认为，在金属污染土壤中，生境质量的影响可能比金属浓度对 O. nitens 的生物适应性（幼体产量）更为重要。
