PDF(Pubmed)
Abstract：
Sampling groundwater biodiversity is difficult because of limited access and issues with species identification. Environmental DNA (eDNA) provides a viable alternative to traditional sampling approaches, however limited knowledge of the abundance and fate of DNA in groundwater hinders the interpretation of data from these environments. Groundwater environments are dark and have lower oxygen concentrations and microbial activity than surface waters. Consequently, assumptions about DNA fate in surface ecosystems may not apply to groundwaters. Here, we test the longevity and transport of eDNA in groundwater within a static microcosm and a flow-through mesocosm. A variety of invertebrates were placed within a mesocosm and microcosm to enable DNA shedding, and then removed. DNA persisted for up to 5 weeks after their removal in the static experiment and was detected between 9 and 33 days in the flow-through experiment. Sediments and water both proved important for eDNA detection. Crustacean DNA was detected sporadically and unpredictably, whereas non-crustacean DNA was detected more frequently despite their lower densities. We suggest that detecting crustaceans poses a challenge to utilising eDNA approaches for stygofauna monitoring. This is confounded by the scarcity of sequences for stygofauna in reference databases. Further research is needed before eDNA alone can be routinely employed for stygofauna detection.
摘要：
由于获取有限和物种识别问题，很难对地下水生物多样性进行采样。环境DNA（eDNA）为传统采样方法提供了可行的替代方案，然而，对地下水中DNA的丰度和命运的了解有限，阻碍了对这些环境中数据的解释。地下水环境黑暗，氧气浓度和微生物活性低于地表水。因此,关于地表生态系统中DNA命运的假设可能不适用于地下水。这里,我们在静态微观世界和流通中观世界中测试了eDNA在地下水中的寿命和运输。将各种无脊椎动物置于中观和微观世界中，以使DNA脱落，然后删除。DNA在静态实验中去除后持续长达5周，并在流过实验中检测到9至33天。沉积物和水都被证明对eDNA检测很重要。甲壳动物的DNA被偶尔和不可预测地检测到，尽管密度较低，但非甲壳动物DNA的检测频率更高。我们建议检测甲壳类动物对利用eDNA方法进行stygofauna监测构成挑战。这与参考数据库中stygofauna序列的稀缺性有关。在单独使用eDNA进行常规检测之前，还需要进一步的研究。
