BIORETS: Conserving water resources and riparian biodiversity in a changing desert climate

淡水是生态系统和人类的重要资源。在干旱地区，从河流取水供城市和农业使用已造成河岸和水生生境及其栖息生物群的严重损失。随着旱地河流干涸，与这些水体的文化联系也受到负面影响，包括管理这些河流数千年的土著人民。然而，废水处理厂技术的最新进展已经产生了高质量的经处理的废水，可用于恢复脱水河流的流量和生态功能。在亚利桑那大学（UA）的生物科学教师研究经验（BIORETS）项目中，三组教师参与者将与生态学家和市政自然资源管理人员合作，解决两个主要的基于地点的研究问题。首先，污水的排放如何影响亚利桑那州南部城市圣克鲁斯河及其沿岸的水生和河岸物种的生物多样性？第二，随着新物种的回归，这些新流动的生态系统中的生态群落是如何随时间变化的？教师们将与亚利桑那大学的学术导师以及托霍诺奥哈姆和帕斯夸亚基部落的成员合作，收集和分析数据。教师还将为K-12年级的学生开发课程，让他们参与生态研究，了解水资源保护，并重振社区与河流的联系。从历史上看，处理过的污水通常水质较差，并使接收污水的河流的生态条件恶化。尽管污水处理厂的升级极大地改善了出水水质，但关于出水在多大程度上可以恢复干旱河流的生态系统功能以及河岸和水生生物多样性，仍然存在很大的知识空白。解决这些差距很重要，因为对废水有许多相互竞争的需求（例如，农业或高尔夫球场灌溉），这可能会减少其恢复河流流量的可用性。此外，在这些新型城市生态系统中可以研究许多基本的生态过程，包括物种更替和优先效应等群落组装机制。在UA的BIORETS项目中，教师和研究人员将在三年内量化河流三个新湿润河段的多个分类类群（水生无脊椎动物，河岸鸟类和哺乳动物以及湿地植物）的多样性和群落结构，并将观察到的模式与附近干燥河段同时收集的数据进行比较。总之，这些数据将阐明新的生态系统中社区聚集的机制，同时也为市政管理者提供实时生态数据，为水资源管理决策提供信息，提高城市的可持续性。这项研究的结果将回答重要的生态问题，形成圣克鲁斯盆地的水管理决策，并为其他城市提供一个模型方法来恢复脱水河流的流量。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Fresh water is a critical resource for both ecosystems and humans. In arid regions, water withdrawals from rivers for urban and agricultural use have resulted in dramatic losses of riparian and aquatic habitats and their resident biota. As arid-land rivers dry, cultural connections to these water bodies are also negatively affected, including those of Indigenous peoples that have stewarded these rivers for millennia. However, recent advances in wastewater treatment plant technologies have resulted in high quality treated effluent that could be useful for restoring flow and ecological function in dewatered rivers. In this Research Experiences for Teachers Sites in Biological Sciences (BIORETS) program at the University of Arizona (UA), three cohorts of teacher participants will collaborate with ecologists and municipal natural resource managers to address two primary place-based research questions. First, how does the release of effluent affect the biodiversity of aquatic and riparian species in and along the urban Santa Cruz River in southern Arizona? Second, how do ecological communities change over time in these newly flowing ecosystems as new species return to the system? Teachers will work with academic mentors at UA, as well as with members of the Tohono O’odham and Pascua Yaqui tribes, to collect and analyze data. Teachers also will develop curricula for their K-12 students to participate in ecological studies, learn about water resource conservation, and reinvigorate community connections to the river. Historically, treated effluent was generally of poor water quality and it degraded ecological conditions in rivers that received effluent. Although wastewater treatment plant upgrades have greatly improved effluent water quality, large knowledge gaps remain regarding how well effluent can restore ecosystem function and riparian and aquatic biodiversity in arid-land rivers. These gaps are important to address because there are many competing demands for effluent (e.g., agricultural or golf course irrigation) which could reduce its availability to restore flow in rivers. Additionally, numerous basic ecological processes can be studied in these novel urban ecosystems, including community assembly mechanisms such as species turnover and priority effects. In this BIORETS program at UA, teachers and researchers will quantify the diversity and community structure of multiple taxonomic groups (aquatic invertebrates, riparian birds and mammals, and wetland plants) in three newly rewetted reaches of the river over three years, and compare observed patterns with data collected concurrently from nearby dry reaches. Together, these data will elucidate mechanisms of community assembly in novel ecosystems while also providing municipal managers with real-time ecological data to inform water resource management decisions and enhance urban sustainability. The results of this research will answer important ecological questions, shape water management decisions in the Santa Cruz basin, and provide a model approach for other cities to adopt for restoring flow in dewatered rivers.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.