环境DNA技术发展及其在长江流域水生生态学领域的应用研究进展

Research progress of environmental DNA technology and its application in ecology of the Yangtze River basin

长江流域鱼类资源丰富、生物多样性高。近年来,受人为干扰、环境变化等因素影响,鱼类资源急剧衰退,全面了解该流域水生生态学信息、进行长江大保护迫在眉睫。随着分子生物学技术的发展,环境DNA技术应运而生,其相比于传统调查方式更加高效、灵敏,应用领域更广;该技术的灵敏性使其非常适合于检测濒危物种、低密度物种入侵、瞬时和隐秘物种的存在,特别是当检测低密度物种的采样工作难以控制时,其敏感性、简便性和降低危害性的优势愈加显现出来。因此,该技术已被广泛应用于食品微生物、生物监测、群落生态学、古环境、保护生物学和生物入侵等领域的研究。介绍了环境DNA定义、发展史、研究方法与优劣势,在此基础上概述了其在长江流域水生生态学领域的应用研究进展,最后展望了环境DNA技术与环境RNA技术相结合的技术革新以及新一代测序手段、大数据及机器智能技术多技术结合助力该领域研究的前景,以期为长江流域持续性生态学监测提供借鉴和参考。

Yangtze River is the longest waterway in China and has rich fishery resource.But over the years fishery resources have plummeted due to pressures including pollution,unsustainable fishing,and damming and draining of rivers and wetlands.Traditional fishery resource survey methods are often based on specimen collection and morphological identification,which are time-consuming and ineffective.Additionally,these methods are unable to conduct the type of large-scale,continuous ecological surveys for many conservation initiatives.Therefore there is an urgent need to find a new approach of monitoring to meet the growing biodiversity surveillance needs.As molecular biology tools have improved,environmental DNA technology has been introduced into the field of ecology,showing great potential to meet conservation needs.Environmental DNA technology is defined as DNA isolated from environmental samples,including microbial,meiofaunal and macrobial taxa,in contrast to genomic DNA extracted directly from specimens.This technology has been widely used in food microbiology,biological monitoring,community ecology,paleo environmental research,conservation biology and biological invasion.Environmental DNA technology requirements for sampling are low,it can detect organisms in the environment more comprehensively,also can detect the relevant information of invasive alien species and cherished protected species,especially when the sampling of low-density species is difficult to control,its sensitivity,simplicity and harm reduction advantages are increasingly apparent.Environmental DNA technology also has some limitations:there is cross-infection during the experiment,and there are false positives and false negatives in the results,and it is impossible to distinguish between species life and development.By reviewing the definition,development history,research methods,advantages and disadvantages of environmental DNA,the research progress of environmental DNA technology and its application in the Yangtze River basin ecology are explored and analyzed.Environmental DNA technology can be applied to the ecology of the Yangtze River basin,including biodiversity monitoring,biomass assessment,ecological health assessment,etc.The relevant indicators of environmental DNA technology can indirectly display species-related information,predict ecosystem processes,guide management decisions related to large ecosystems,and then supplement and improve the ecological health evaluation system.At the same time,the data obtained by environmental DNA technology can also be applied in the assessment of breeding and release effects of important species in the Yangtze River basin,and assist in optimizing and improving the formulation of fishery management policies.In the future,in order to properly apply environmental DNA technology in the field of aquatic biomonitoring,researchers should focus on the following aspects:technological innovation of the combination of environmental DNA technology and environmental RNA technology,the combination of next-generation sequencing methods,big databases and machine intelligence technology.