The response of mountain lakes to environmental change

Lakes act as sentinels of environmental change by incorporating forcing across scales: climate scales, catchment scales, and within-lake scales. To fully understand the changes that lake ecosystems undergo, we must explore past changes and present trends, both on a fine scale – in individual lake systems – and on a macroscale –across broad geographic regions. Mountain lakes are useful as study systems because they are often remote and generally free of direct human influence. However, external impacts still affect mountain lake ecosystems, both through input of exogenous material and air temperature warming that influences the formation and breakup of lake ice. In this work, we use a combination of sediment records, intensive sampling, and remote sensing to understand the effects of climate change on mountain lake ecosystems. We refine our understanding of winter mountain lake hydrology through three studies that address: 1. Whether aeolian dust records in mountain lake cores capture deposition rate changes of exogenous dust input 2. Whether North American mountain lake ice cover period is changing 3. How mountain lake ecohydrology responds to shifts in ice cover timing (i.e., ice phenology) We found heterogeneity in mountain lake responses across scales in each of our studies. In the case of exogenous dust deposition to lakes, sediment cores revealed that dust can be an important source of nutrients to lakes; however, sediment records do not reveal changing rates of deposition between the distant and recent past. Apparent changes are rather an artifact of timescale dependence. When taking a continental-scale view of ice phenology, using a remote sensing dataset of 1,629 lakes, we find that ice phenology patterns do not readily cohere with ice phenology patterns from single lakes or lakes within a similar geographic region. Instead, lake ice phenology shows heterogeneous responses in different geographic regions (e.g., between the Sierra Nevada and the Rocky Mountains), hinting at potential resiliency to climate forcing in different regions of North America. Lastly, using high-frequency time series of dissolved oxygen concentration across morphologically distinct lakes, I found that lakes experiencing similar winter conditions showed heterogeneous oxygen dynamics along a depth gradient. Shallow lakes respond to winter ice cover conditions by depleting oxygen more quickly than deep lakes. I additionally explore the effects of sediment organic matter and winter meteorological dynamics. I anticipate that these results will be useful for understanding linkages between broader climate forcing. As air temperatures increase, heterogeneous landscape factors may confound the anticipated physical, chemical, and ecological lake responses, leading to questions about how lakes may show variations in timing or resiliency in response to climate change in the future

Wildfire Smoke Effects on Lake-Habitat Specific Metabolism: Toward a Conceptual Understanding

The impacts of wildfire smoke on lake habitats remains unclear. We determined the metabolic response to smoke in the epi-pelagic and two littoral habitats in Castle Lake, California. We compared light regime, gross primary production, ecosystem respiration, and net ecosystem production in years with and without smoke. During the smoke period incident ultraviolet-B (UV-B) radiation and photosynthetically active radiation (PAR) decreased by 53% and 28%, respectively, while the water column extinction coefficient of UV-B and PAR increased by 20% and 18% respectively. Epi-pelagic productivity increased during smoke cover because of decreased solar inputs. PAR values remained sufficient to saturate productivity, suggesting observed differences were primarily the result of changes in UV-B. Littoral-benthic productivity did not change, possibly reflecting adaptation to high-intensity UV-B light in these habitats. Our results highlight the importance of understanding how prolonged wildfire smoke alters the amount of energy produced from specific habitats in lakes.Fil: Scordo, Facundo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. University of Nevada; Estados UnidosFil: Sadro, Steven. University of California at Davis; Estados UnidosFil: Culpepper, Joshua. University of California at Davis; Estados Unidos. University of Nevada; Estados UnidosFil: Seitz, Carina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. University of Nevada; Estados UnidosFil: Chandra, Sudeep. University of Nevada; Estados Unido

Early Career Aquatic Scientists Forge New Connections at Eco-DAS XV

A sense of kuleana (personal responsibility) in caring for the land and sea. An appreciation for laulima (many hands cooperating). An understanding of aloha ’āina (love of the land). The University of Hawai’i at Manoa hosted the 2023 Ecological Dissertations in Aquatic Sciences (Eco-DAS) program, which fostered each of these intentions by bringing together a team of early career aquatic ecologists for a week of networking and collaborative, interdisciplinary project development (Fig. 1)

Approach to Onboarding Emergency Medical Services (EMS) Data Into a Syndromic Surveillance System

ObjectiveTo describe the strategy and process used by the Florida Department of Health (FDOH) Bureau of Epidemiology to onboard emergency medical services (EMS) data into FDOH’s syndromic surveillance system, the Electronic Surveillance System for the Early Notification of Community-based Epidemics (ESSENCE-FL).IntroductionSyndromic surveillance has become an integral component of public health surveillance efforts within the state of Florida. The near real-time nature of these data are critical during events such as the Zika virus outbreak in Florida in 2016 and in the aftermath of Hurricane Irma in 2017. Additionally, syndromic surveillance data are utilized to support daily reportable disease detection and other surveillance efforts. Although syndromic systems typically utilize emergency department (ED) visit data, ESSENCE-FL also includes data from non-traditional sources: urgent care center visit data, mortality data, reportable disease data, and Florida Poison Information Center Network (FPICN) data. Inclusion of these data sources within the same system enables the broad accessibility of the data to more than 400 users statewide, and allows for rapid visualization of multiple data sources in order to address public health needs. Currently, the ESSENCE-FL team is actively working to incorporate EMS data into ESSENCE-FL to further increase public health surveillance capacity and data visualization.MethodsThe ESSENCE-FL team worked collaboratively with various public health program stakeholders to bring EMS data, aggregated by the FDOH Bureau of Emergency Medical Oversight Emergency Medical Services Tracking and Reporting System (EMSTARS) team, into ESSENCE-FL. The ESSENCE-FL team met with the EMSTARS team to discuss use cases, demonstrate both systems, and to obtain project buy-in and support. Initial project meetings included review of ESSENCE-FL system support, user types (roles and access), as well as data security and compliance. An overall project timeline was established, and deliverables were added into system support contracts. Multiple stakeholders, across disciplines representing each key use case, reviewed the Florida version of the National Emergency Medical Services Information System (NEMSIS) version 3.4 data dictionary to identify program-specific data element needs. An element scoring spreadsheet was returned to the ESSENCE-FL team. These scores were aggregated and discordant scores were reviewed by the ESSENCE-FL team. A one-month extract of EMS data was reviewed to assess variable completeness and relevance. Monthly team meetings facilitated the final decisions on the data elements by leveraging lessons learned through onboarding other data sources, findings from the analysis of the one-month extract, stakeholder comments, and advice from other states known to be leveraging EMS data for public health surveillance.ResultsThrough a collaborative and broad approach with partners, the ESSENCE-FL team attained stakeholder buy-in and identified 81 data elements to be included in the EMS feed to ESSENCE-FL. The final list of data elements was determined to best support health surveillance of this population prior to presenting to the ED. The inclusion of the EMS data in ESSENCE-FL will increase the epidemiologic characterization and analysis of the opioid epidemic in Florida. Additional key use cases identified during this project included enhanced injury surveillance, enhanced occupational health surveillance, and characterization of potential differences between EMS and ED visits.ConclusionsThis comprehensive approach can be used by other jurisdictions considering adding EMS data to their syndromic surveillance systems. When considering onboarding a new data source into a surveillance system, it is important to work closely with stakeholders from disciplines representing each of the key use cases to broaden buy-in and support for the project. Through employing this comprehensive approach, syndromic surveillance systems can be better developed to include data that are widely utilizable to many different stakeholders in the public health community

Do years with different ice-out dates influence pelagic and littoral metabolism in a lake?

The duration of winter ice cover plays a key role in lake metabolism. We analyzed metabolism rates in a littoral (L) and pelagic (P) habitats of a subalpine lake using a metabolism model based on free-water dissolved oxygen during years with early, middle, and late ice-out dates. Gross primary production (GPP) and respiration (R) at L was up to 7.8 and 5.5 times, respectively, higher than at P. GPP and R in both sites was lower during the years with early ice-out (P = 30%, L= 35% decrease) and late ice-out (P = 30%, L= 61% decrease) compared to middle ice-out years. Also, both sites exhibited lower R during the years with early ice-out (P = 26%, L= 41% decrease) and late ice-out (P = 32%, L= 46% decrease). Finally, middle values of net ecosystem production (NEP) were positive during more than 80% of the period analyzed, indicating autotrophic-dominated lake metabolism with one exception in L. In the late ice-out year, L had a negative middle value of NEP during 97% of the analyzed period, showing a shift to heterotrophic metabolism. This study demonstrates how metabolic rates change in different habitats of the lake in years with different ice-out dates. Low heat content on the lake and wash of nutrients and producers late in the ice-free season may have reduced the metabolism during the year with late ice-out. The depletion of nutrients and high grazing rates could have reduced metabolism during the year with early ice-out.Fil: Scordo, Facundo. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Sudeep, Chandra. University Of Nevada; Estados UnidosFil: Lotting, Noah R.. University of Wisconsin; Estados UnidosFil: Culpepper, Joshua. University Of Nevada; Estados UnidosFil: Kelson, Suzanne J.. University Of Nevada; Estados UnidosFil: Simons, James. University Of Nevada; Estados UnidosFil: Krynak, Edward M.. University Of Nevada; Estados UnidosFil: Seitz, Carina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Geología; ArgentinaFil: Suenaga, Erin. University Of Nevada; Estados UnidosThe Global Lake Ecological Observatory Network All Hands' MeetingEstados UnidosGlobal Lake Ecological Observatory Networ

Smoke from regional wildfires alters lake ecology

Wildfire smoke often covers areas larger than the burned area, yet the impacts of smoke on nearby aquatic ecosystems are understudied. In the summer of 2018, wildfire smoke covered Castle Lake (California, USA) for 55 days. We quantified the influence of smoke on the lake by comparing the physics, chemistry, productivity, and animal ecology in the prior four years (2014?2017) to the smoke year (2018). Smoke reduced incident ultraviolet-B (UV-B) radiation by 31% and photosynthetically active radiation (PAR) by 11%. Similarly, underwater UV-B and PAR decreased by 65 and 44%, respectively, and lake heat content decreased by 7%. While the nutrient limitation of primary production did not change, shallow production in the offshore habitat increased by 109%, likely due to a release from photoinhibition. In contrast, deep-water, primary production decreased and the deep-water peak in chlorophyll a did not develop, likely due to reduced PAR. Despite the structural changes in primary production, light, and temperature, we observed little significant change in zooplankton biomass, community composition, or migration pattern. Trout were absent from the littoral-benthic habitat during the smoke period. The duration and intensity of smoke influences light regimes, heat content, and productivity, with differing responses to consumers.Fil: Scordo, Facundo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. University Of Nevada; Estados UnidosFil: Chandra, Sudeep. University Of Nevada; Estados UnidosFil: Suenaga, Erin. University Of Nevada; Estados UnidosFil: Kelson, Suzanne J.. University Of Nevada; Estados UnidosFil: Culpepper, Joshua. University Of Nevada; Estados UnidosFil: Scaff, Lucia. University of Saskatchewan; CanadáFil: Tromboni, Flavia. University Of Nevada; Estados UnidosFil: Caldwell, Timothy J.. University Of Nevada; Estados UnidosFil: Seitz, Carina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; ArgentinaFil: Fiorenza, Juan Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; ArgentinaFil: Williamson, Craig E.. Miami University; Estados UnidosFil: Sadro, Steven. University of California at Davis; Estados UnidosFil: Rose, Kevin C.. Rensselaer Polytechnic Institute; Estados UnidosFil: Poulson, Simon R.. University Of Nevada; Estados Unido

Better Together: Early Career Aquatic Scientists Forge New Connections at Eco‐DAS XV

A sense of kuleana (personal responsibility) in caring for the land and sea. An appreciation for laulima (many hands cooperating). An understanding of aloha 'āina (love of the land). The University of Hawai'i at Manoa hosted the 2023 Ecological Dissertations in Aquatic Sciences (Eco-DAS) program, which fostered each of these intentions by bringing together a team of early career aquatic ecologists for a week of networking and collaborative, interdisciplinary project developmen