土霉素是一种典型的抗生素类新污染物,具有使用量大、生态毒性强等特点,其环境基准标准和水生态风险受到学界广泛关注.本文基于美国毒理数据库、Web of Science、中国知网等相关数据库,收集整理了土霉素对我国淡水生物的毒性数据和水环...土霉素是一种典型的抗生素类新污染物,具有使用量大、生态毒性强等特点,其环境基准标准和水生态风险受到学界广泛关注.本文基于美国毒理数据库、Web of Science、中国知网等相关数据库,收集整理了土霉素对我国淡水生物的毒性数据和水环境暴露数据,制定了保护淡水生物的水质基准,并进行了风险评估.结果表明:(1)依据《中国动物志》和《淡水生物水质基准推导技术指南》等,对毒性数据的物种和试验条件进行筛选,最终土霉素急性毒性数据涉及5门10科13种,最敏感物种为模糊网纹溞(Ceriodaphnia dubia);慢性数据涉及3门9科10种,最敏感物种为水蕴草(Egeria densa).(2)物种敏感度分布法研究表明,急性数据符合逻辑斯蒂分布模型,推导出的短期水质基准为61.2μg/L;慢性毒性数据符合正态分布模型,推导出的长期水质基准为18.7μg/L.(3)毒性百分数排序法推导的基准最大浓度为34.0μg/L,基准连续浓度为7.4μg/L.(4)共搜集近15年(2007年1月—2022年3月)我国主要水体土霉素浓度数据803条,浓度范围为0.1~97433.8 ng/L,北方流域的土霉素浓度整体高于南方,采用风险熵值法和概率法的研究表明,土霉素污染对我国淡水生物的环境风险整体较低,仅海河的子牙河支流生态风险较高(风险熵RQ>1).结合基准及我国污染特点,认为我国保护淡水生物的土霉素地表水环境质量标准建议值为18.7μg/L.研究结果对土霉素等新污染物的环境管理、风险评估以及本土物种保护的水质标准制订具有借鉴作用.展开更多
The invasion of exotic plants is a severe problem due to its tremendous damage and impact. The management and assessments of exotic plants are very important. The effective assessments include:①the properties related...The invasion of exotic plants is a severe problem due to its tremendous damage and impact. The management and assessments of exotic plants are very important. The effective assessments include:①the properties related to establishment of exotic plant.② the factors which influence the spread of exotic plants;③ the impacts of exotic species. When evaluating exotic species, the three aspects should be integrated to assess exotic plants. Every guideline of assessment plays different role in assessment of different exotic species. At the same time, it is becoming increasingly important to predict which species will invade an area alien to them and to estimate what harm they can do. Three ways of predicting invasions of exotic species,should be conducted. Models may help us to evaluate the influence of exotic species. Managing exotic plants, especially the exthose with large distribution area, requires a coordinated strategy based on cooperation among all departments, which include forestry, agriculture, fishery, all land managers and so on. This strategy emphasizes on cooperation, education, and science, and is based on integrated management techniques. The management is divided into three steps. The first step is to effectively prevent new invasion, the second step is to control and eliminate exotic plants, in which mechanical methods, chemical means, and biocontrol technologies are used. Sometimes, the three ways are integrated in order to obtain better results. The third step is to effectively restore native vegetation and prevent reinvasion.展开更多
文摘The invasion of exotic plants is a severe problem due to its tremendous damage and impact. The management and assessments of exotic plants are very important. The effective assessments include:①the properties related to establishment of exotic plant.② the factors which influence the spread of exotic plants;③ the impacts of exotic species. When evaluating exotic species, the three aspects should be integrated to assess exotic plants. Every guideline of assessment plays different role in assessment of different exotic species. At the same time, it is becoming increasingly important to predict which species will invade an area alien to them and to estimate what harm they can do. Three ways of predicting invasions of exotic species,should be conducted. Models may help us to evaluate the influence of exotic species. Managing exotic plants, especially the exthose with large distribution area, requires a coordinated strategy based on cooperation among all departments, which include forestry, agriculture, fishery, all land managers and so on. This strategy emphasizes on cooperation, education, and science, and is based on integrated management techniques. The management is divided into three steps. The first step is to effectively prevent new invasion, the second step is to control and eliminate exotic plants, in which mechanical methods, chemical means, and biocontrol technologies are used. Sometimes, the three ways are integrated in order to obtain better results. The third step is to effectively restore native vegetation and prevent reinvasion.