Extending Water Resources Performance Metrics to River Ecosystems

A persistent challenge in integrated water management is the ability to accurately evaluate human and ecological tradeoffs. Two-dimensional (2D) hydraulic models are frequently used to evaluate water management alternatives concerning aquatic species physical habitat needs or preferences. Recent studies have assessed the timing or duration of suitable habitat conditions, but no standardized approach exists to integrate and interpret ecohydraulic model outputs within a water management framework. Such an approach is needed to maximize the information obtained from model outputs and to facilitate communication between river scientists and water managers. This study presents a general framework to aggregate and summarize 2D hydraulic model outputs by adapting the traditional water resources metrics of reliability, resilience, vulnerability, and sustainability. Just as these metrics are typically used to quantify distinct aspects of water resources performance, applying them to ecohydraulic conditions facilitates interpretation of ecological performance and human-ecosystem water management tradeoffs. This paper examines the utility and limitations of the proposed framework and metrics in a simple application to fall-run Chinook salmon in a typical Mediterranean-montane stream

Economic effects of a reservoir re-operation policy in the Rio Grande/Bravo for integrated human and environmental water management

Study region: The study region is the Big Bend Reach of the Rio Grande/Bravo, from Luis L. Leon reservoir in the Rio Conchos to Amistad reservoir in the Rio Grande/Bravo mainstem. This reach is part of the Rio Grande trans-boundary river basin between United States and Mexico, an area of recognized environmental and socioeconomic significance by both countries. Study focus: A central challenge of Integrated Water Resources Management is the design and implementation of policies to allocate water to both humans and the environment in a sustainable manner. This study uses the results from a water-planning model of the Big Bend Reach of the Rio Grande/Bravo to quantify and compare the economic benefits of two water management policies: business as usual (Baseline) policy and a proposed reservoir re-operation policy to provide environmental flows (EFs). New hydrological insights: This study determines the economic feasibility of the EF policy. Results show that a proposed Environmental Flow policy would increase irrigated agriculture profit, slightly decrease recreational activities profit, and reduce costs from flood damage and environmental restoration compared to the baseline policy. In addition to supporting ecological objectives, the proposed EF policy would increase the economic benefits of water management objectives

Projected Effects of Temperature and Precipitation Variability Change on Streamflow Patterns Using a Functional Flows Approach

Abstract Streamflow patterns are shifting with climate change, and these shifts pose increasing risk to freshwater ecosystems. These emerging changes must be linked with ecological functions of river systems to understand how climate change may affect freshwater biota. In this study we used a functional flows approach to analyze the ecological effects of changing streamflow patterns in snowmelt‐dominated watersheds of the Sierra Nevada mountains of California. Our climate change modeling method combined ensemble Global Climate Models (GCMs) and decision scaling methods to incorporate the effects of GCM‐projected changes in precipitation variability on streamflow patterns. Of climate parameters explored, air temperature causes the most change in functional flows, although precipitation variability compounds changes driven by air temperature. The greatest changes in ecologically‐relevant streamflow patterns manifest as longer and drier dry season conditions, earlier snowmelt recession, and higher‐magnitude peak flows. Although the directions of changes in functional flow metrics are largely consistent across models and watersheds, the magnitude of change depends strongly on human emissions levels. The analytical approach used in this study can serve as a model for integrating multiple approaches in hydroclimatic assessment of ecological change, and the results can help prioritize specific aspects of the flow regime for restoration efforts

Quantifying the contribution of major carbon producers to increases in vapor pressure deficit and burned area in western US and southwestern Canadian forests

Increases in burned forest area across the western United States and southwestern Canada over the last several decades have been partially driven by a rise in vapor pressure deficit (VPD), a measure of the atmosphere’s drying power that is significantly influenced by human-caused climate change. Previous research has quantified the contribution of carbon emissions traced back to a set of 88 major fossil fuel producers and cement manufacturers to historical global mean temperature rise. In this study, we extend that research into the domain of forest fires. We use a global energy balance carbon-cycle model, a suite of climate models, and a burned area (BA) model to determine the contribution of emissions traced to the major carbon producers to the long-term increase in VPD during 1901–2021 and to cumulative forest fire area during 1986–2021 in the western US and southwestern Canada. Based on climate model data, we find that emissions traced to these carbon producers contributed 48% (interquartile range (IQR) 38%–63%) of the long-term rise in VPD between 1901 and 2021. BA modeling indicates that these emissions also contributed 37% (IQR 26%–47%) of the cumulative area burned by forest fires between 1986 and 2021 in the western US and southwestern Canada. The increase in VPD in this region is linked to both increased fire activity and the region’s current and prolonged megadrought. As loss and damage from these hazards mounts, this research can inform public and legal dialogues regarding the responsibility carbon producers bear for addressing past, present, and future climate risks associated with fires and drought in the western US and southwestern Canada

Underrepresented, understudied, underserved: Gaps and opportunities for advancing justice in disadvantaged communities

A common approach in scientific research and policy is a commitment to develop projects or legislation trying to improve problems experienced by low-income and rural communities; however, lack of interaction with community members during the process tends to produce unsatisfactory results. We visited disadvantaged communities in the San Joaquin Valley of California and interviewed local stakeholders (community members and leaders, policy advocates, attorneys, and educators). Then we analyzed a corpus related to disadvantaged communities from a pool of California-related publications containing 154,000 scientific papers, 2.6 million newspaper articles, and 11,000 state legislation bills from 2017 to 2020 to estimate the frequency and quality of disadvantaged community representation. Here we present our findings describing the biases and gaps of knowledge by scientific papers, California newspaper articles, and legislation bills with respect to disadvantaged communities in California, and we suggest opportunities for scientists, media communicators, and policymakers to amplify the voices of these stakeholders. In all corpus categories, disadvantaged communities are underrepresented: about one in four Californians live in disadvantaged communities, but only one in 2000 news articles and scientific papers cover them. The concerns and priorities of disadvantaged communities do not match the public perspective of them depicted by the corpus. Developing effective policies requires addressing place-specific nuances and co-occurrence of structural inequities in partnership with local stakeholders. Holistic coverage in newspapers and community-based approaches are necessary platforms to increase awareness and sensibility about disadvantaged communities, helping tailor policy solutions, and building the political leverage needed to implement them

Water, environment, and socioeconomic justice in California: A multi-benefit cropland repurposing framework

Low-income, rural frontline communities of California's Central Valley experience environmental and socioeconomic injustice, water insecurity, extremely poor air quality, and lack of fundamental infrastructure (sewage, green areas, health services), which makes them less resilient. Many communities depend financially on agriculture, while water scarcity and associated policy may trigger farmland retirement further hindering socioeconomic opportunities. Here we propose a multi-benefit framework to repurpose cropland in buffers inside and around (400-m and 1600-m buffers) 154 rural disadvantaged communities of the Central Valley to promote socioeconomic opportunities, environmental benefits, and business diversification. We estimate the potential for (1) reductions in water and pesticide use, nitrogen leaching, and nitrogen gas emissions, (2) managed aquifer recharge, and (3) economic and employment impacts associated with clean industries and solar energy. Retiring cropland within 1600-m buffers can result in reductions in water use of 2.18 km3/year, nitrate leaching into local aquifers of 105,500 t/year, greenhouse gas emissions of 2,232,000 t CO2-equivalent/year, and 5388 t pesticides/year, with accompanying losses in agricultural revenue of US$4213 million/year and employment of 25,682 positions. Buffer repurposing investments of US$27 million/year per community for ten years show potential to generate US$101 million/year per community (total US$15,578 million/year) for 30 years and 407 new jobs/year (total 62,697 jobs/year) paying 67 % more than prior farmworker jobs. In the San Joaquin Valley (southern Central Valley), where groundwater overdraft averages 2.3 km3/year, potential water use reduction is 1.8 km3/year. We have identified 99 communities with surficial soils adequate for aquifer recharge and canals/rivers within 1600 m. This demonstrates the potential of managed aquifer recharge in buffered zones to substantially reduce overdraft. The buffers framework shows that well-planned land repurposing near disadvantaged communities can create multiple benefits for farmers and industry stakeholders, while improving quality of life in disadvantaged communities and producing positive externalities for society

Global attitudes in the management of acute appendicitis during COVID-19 pandemic: ACIE Appy Study

Background: Surgical strategies are being adapted to face the COVID-19 pandemic. Recommendations on the management of acute appendicitis have been based on expert opinion, but very little evidence is available. This study addressed that dearth with a snapshot of worldwide approaches to appendicitis. Methods: The Association of Italian Surgeons in Europe designed an online survey to assess the current attitude of surgeons globally regarding the management of patients with acute appendicitis during the pandemic. Questions were divided into baseline information, hospital organization and screening, personal protective equipment, management and surgical approach, and patient presentation before versus during the pandemic. Results: Of 744 answers, 709 (from 66 countries) were complete and were included in the analysis. Most hospitals were treating both patients with and those without COVID. There was variation in screening indications and modality used, with chest X-ray plus molecular testing (PCR) being the commonest (19\ub78 per cent). Conservative management of complicated and uncomplicated appendicitis was used by 6\ub76 and 2\ub74 per cent respectively before, but 23\ub77 and 5\ub73 per cent, during the pandemic (both P < 0\ub7001). One-third changed their approach from laparoscopic to open surgery owing to the popular (but evidence-lacking) advice from expert groups during the initial phase of the pandemic. No agreement on how to filter surgical smoke plume during laparoscopy was identified. There was an overall reduction in the number of patients admitted with appendicitis and one-third felt that patients who did present had more severe appendicitis than they usually observe. Conclusion: Conservative management of mild appendicitis has been possible during the pandemic. The fact that some surgeons switched to open appendicectomy may reflect the poor guidelines that emanated in the early phase of SARS-CoV-2