Understanding the recovery of ecosystems from pulp and paper mill effluents

20年来，一些纸浆和造纸厂的废水对环境的潜在影响已经得到了很好的研究，但对于影响的存在、所研究的端点的生态相关性以及应引起关注的反应的大小，仍存在相当大的争议。加拿大纸浆和造纸业在过去十年里经历了巨大的变化，公司合并，许多较老或较小的工厂关闭，以及财务失败，运营中的工厂数量从1991年的130家减少到2009年的80家。在以前有长期研究和监测计划的设施中，关闭的时间梯度提供了一个独特的机会，可以了解减少压力后鱼类种群恢复的时间框架。我们可以评估在监测项目中广泛使用的终端的敏感性、特异性和相关性，以改进标准化的监测方法，并了解关闭后工业废水的潜在遗留问题。这些信息对于解决限制政府监管机构、科学家和行业在理解纸浆和造纸厂废水影响方面达成共识的能力的知识差距至关重要。我们将通过与监管机构和行业的伙伴关系，开发和完善评估工具，以提高我们检测和应对相关和重大环境影响的能力。这种改进的方法将显著提高我们的能力：1)评估工业废水对环境的风险；2)确定可用于克服特定地点挑战的监测最佳做法；3)调查生态系统变化的恢复力、可逆性和恢复时间范围，以便更好地了解暴露对水生系统结构和功能的影响。这些是必须克服的关键挑战，以便继续开发有意义的监测工具，帮助保护加拿大和国际环境中的公共资源。

The potential for effluents from some pulp and paper mills to affect the environment has been well studied for two decades but there continues to be considerable controversy over the existence of effects, the ecological relevance of endpoints studied, and the magnitude of responses that should arouse concern. The Canadian pulp and paper industry has undergone considerable change over the past decade, with consolidation of companies, closure of many older or smaller mills, and financial failures that have reduced the numbers of operating mills from >130 in 1991 to <80 in 2009. The temporal gradient of closure at facilities where long term research and monitoring programs were previously in place offers a unique opportunity to understand the time frame to recovery of fish populations after reducing stress. We can evaluate the sensitivity, specificity, and relevance of endpoints that are widely used in monitoring programs in order to improve standardized monitoring approaches, and understand the potential legacy of industrial effluents following shutdown. This information is critical to address the knowledge gaps that limit the ability of government regulators, scientists and industries to reach consensus in understanding the impacts of pulp and paper mill effluents. Via partnerships with regulatory organizations and industries, we will develop and refine assessment tools to improve our ability to detect and respond to relevant and significant environmental impacts. This improved approach will significantly enhance our ability to: 1) assess risks to the environment from industrial effluents; 2) determine best practices in monitoring which could be used to overcome site-specific challenges; and 3) investigate the resiliency, reversibility and time scale for recovery of ecosystem changes in order to better understand the consequences of exposures on the structure and function of aquatic systems. These are key challenges which must be overcome to continue the development of meaningful monitoring tools that can help protect public resources in Canadian and international settings.