Development of diagnostic indicators for assessing effects of multiple stressors on stream ecosystem health.

制定诊断指标来评估多种压力源对河流生态系统健康的影响。

• 批准号: RGPIN-2018-03868
• 负责人: AlexanderTrusiak, Alexa
• 金额: $ 2.04万
• 依托单位: University of New Brunswick
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=712298
• 关键词: Development; diagnostic; indicators; assessing; effects

Each contaminant is considered separately in the development of water quality guidelines in Canada using data from single-species toxicity tests. However, neither contaminants nor species exist in isolation. For example, in agricultural systems, aquatic biota are impacted by mixtures of pesticides and nutrients due to spray drift, runoff and erosion. Unfortunately, nutrient enrichment, let alone community complexity, are but rarely considered in ecological risk assessment. Rather, lethal toxicity testing of single stressors in laboratory-reared species is the norm. A more holistic approach is needed. The proposed research will develop a combined approach using existing methods (e.g., lethality and structural indicators of community responses) while adding sublethal, diagnostic indicators (metabolomics, or the total metabolites within an organism) to provide the building blocks needed to diagnose the interactive effects that nutrients and pesticides have on food webs in rivers. This work will: (1) establish the effects of nutrient enrichment and pesticides on riverine insects, both alone and in combination by assessing additive, multiplicative and comparative effects model frameworks; (2) examine the role nutrients may have in masking the effects of pesticides through manipulative mesocosm experiments; and (3) assess the combined effects of nutrient subsidies across pesticide disturbance gradients. Key predictions are that: (1) river insects will respond to non-lethal stress through decreased body size and abundance; (2) negative effects of pesticides may be lessened by mild to moderate nutrient enrichment; and (3) increased nutrient enrichment will worsen the effects of pesticide exposure. The proposed research will train 2 PhD, 4 MSc, and 5 undergraduate students, and increase our knowledge of the interactive effects of nutrient and pesticide exposure in aquatic macroinvertebrate communities. This research will also help move regulatory water quality regimes from simple, single-stressor effects models to a more realistic evaluation of cumulative ecological effects resulting from multiple stressor exposure.

加拿大在制定水质准则时，使用单物种毒性试验的数据分别考虑每种污染物。然而，污染物和物种都不是孤立存在的。例如，在农业系统中，由于喷雾漂移、径流和侵蚀，水生生物群受到农药和营养物混合物的影响。不幸的是，在生态风险评估中很少考虑营养富集，更不用说群落复杂性了。相反，在实验室饲养的物种中进行单一压力源的致死毒性测试是常态。需要一种更全面的方法。