The instrumented buoy on Trout Lake is equipped with a dissolved oxygen sensor, a thermistor chain, and meteorological sensors that provide fundamental information on lake thermal structure, weather conditions, and lake metabolism. Data are usually collected every 10 minutes with occasional periods of 2 minute data for short periods to answer specific questions. The D-Opto dissolved oxygen sensor is 0.5m from the lake surface. Meteorological sensors measure wind speed, wind direction, relative humidity, air temperature, photosynthetically active radiation (PAR), and barometric pressure. Starting in 2005, thermistors were placed every 0.5-1m from the surface through 14m and every 2 to 4m from 14m to the bottom of the water column at 31m. In July 2006, a new thermistor chain was deployed with thermistors placed every meter from the surface through a depth of 19 meters. After correcting for flux to or from the atmosphere and vertical mixing within the water column, high frequency measurements of dissolved gases such as carbon dioxide and oxygen can be used to estimate gross primary productivity, respiration, and net ecosystem productivity, the basic components of whole lake metabolism. Data are averaged to daily values from one minute samples for years 2005 - 2006. Daily values are computed from high resolution data starting in year 2007. Data are averaged to hourly values from one minute samples for years 2005 - 2008, Hourly values are computed from high resolution data starting in year 2009. Hourly and daily values may not be current with high resolution data in the current year. Sampling Frequency: varies for instantaneous sample. averaged to hourly and daily values from one minute samples Number of sites: 1
more »
« less
Nearshore high-frequency temporal water quality observations and process-based modeling of aquatic ecosystem metabolism in Lake Tahoe completed by members of the Blaszczak Lab at the University of Nevada Reno, 2021-2023
The overarching goal of this project was to develop a process-based understanding of how watershed-to-lake connections drive nearshore productivity dynamics in a large oligotrophic mountain lake (Lake Tahoe). We addressed this goal through a combined approach of high-frequency sensor deployment and maintenance, ecosystem metabolism modeling, laboratory incubations, and routine monitoring of water chemistry and other parameters. The data we collected as part of this project and the ecosystem metabolism estimates we generated demonstrate how variable ecosystem productivity is in time and space in the nearshore of Lake Tahoe. Although maintenance of the sensor arrays during the exceptional winter of 2023 was challenging, we were able to capture the data necessary to estimate a complete time series of metabolic activity across two years with very different hydroclimatic conditions. Throughout this project we accomplished the following: 1. We generated over two years of daily estimates of ecosystem metabolism (gross primary productivity, ecosystem respiration, and net ecosystem productivity) from multiple locations on both the east and west shores of the lake and from areas in close proximity to and far away from stream water inflows. 2. We measured ammonium (NH4+) and nitrate (NO3-) concentrations in surface water samples from both Glenbrook and Blackwood creeks and the nearshore of Lake Tahoe for over two years. 3. We quantified rates of NH4+ and NO3- uptake in benthic samples of the dominant substrate type collected during peak streamflow, the receding limb, and baseflow conditions in 2023 from multiple locations in the nearshore using established laboratory incubation methods. 4. Finally, we used a combination of time series models and structural equation modeling to integrate our results and improve understanding of the direct and indirect effects of hydroclimatic variability on observed patterns in ecosystem metabolism in the nearshore. See this git code repository for project analysis: https://github.com/kellyloria/Tahoe-streamflow-and-nearshore-metabolism.
more »
« less
- Award ID(s):
- 2019528
- PAR ID:
- 10588922
- Publisher / Repository:
- Environmental Data Initiative
- Date Published:
- Format(s):
- Medium: X
- Location:
- Lake Tahoe Basin
- Institution:
- University of Nevada, Reno
- Sponsoring Org:
- National Science Foundation
More Like this
-
-
The instrumented raft on Sparkling Lake is equipped with a dissolved oxygen and CO2 sensors, a thermistor chain, and meteorological sensors that provide fundamental information on lake thermal structure, weather conditions, evaporation rates, and lake metabolism. Estimating the flux of solutes to and from lakes requires accurate water budgets. Evaporation rates are a critical component of the water budget of lakes. Data from the instrumented raft on Sparkling Lake includes micrometeorological parameters from which evaporation can be calculated. Raft measurements of relative humidity and air temperature (2m height), wind velocity (2m) ,and water temperatures (from thermistors placed throughout the water column at intervals varying from 0.5 to 3m) are combined with measurements of total long-wave and short-wave radiation data from a nearby shore station to determine evaporation by the energy budget technique. Comparable evaporation estimates from mass transfer techniques are calibrated against energy budget estimates to produce a lake-specific mass transfer coefficient for use in estimating evaporation rates. After correcting for flux to or from the atmosphere and vertical mixing within the water column, high frequency measurements of dissolved gases such as carbon dioxide and oxygen can be used to estimate gross primary productivity, respiration, and net ecosystem productivity, the basic components of whole lake metabolism. Other parameters measured include precipitation, wind direction (beginning in 2008), and barometric pressure (beginning in 2008). Sampling Frequency: one minute with hourly and daily averages provided. Number of sites: 1.more » « less
-
To increase geospatial awareness about local water resources, our team developed learning resources for the 150 km² Lake Sidney Lanier reservoir located in North Georgia, USA. The reservoir is vital for hydroelectric power generation, recreation, tourism, and consumptive uses. Using geospatial analysis in Google Earth Engine (GEE), we analyzed precipitation trends in the watershed using Climate Hazards Group InfraRed Precipitation with Station (CHIRPS) data. We also quantified expansion and contraction of reservoir surface area using Landsat-derived Global Surface Water data. As Lake Sidney Lanier is a managed reservoir, surface water extent fluctuations are related to climatic variables, consumptive use, and hydropower generation. Water temperature varies based on seasonality, water depth, water clarity, and lake stratification. Changing temperature dynamics affect ecosystem health and determine other important water quality parameters such as dissolved oxygen concentrations. Landsat 8 Thermal Infrared Sensor (TIRS) data were used to examine temperature trends over multiple years and investigate the timing of lake stratification and mixing. Highly turbid waters are associated with pollutants and lower water quality and can affect ecosystem productivity by minimizing sunlight penetration into the water column. Sentinel 2 MSI data were processed using a turbidity algorithm to analyze temporal trends and spatial correlations with reservoir inflows. Finally, high concentrations of chlorophyll a were used as a proxy to identify harmful algal blooms. The spatial differences in headwaters and near-dam locations were examined and near real-time satellite data were explored for potential development of early-warning systems to protect ecosystem and human health.more » « less
-
Samples for the analysis of dissolved nutrients were collected during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) from the water column, sea ice cores and from special events/locations (e.g., leads, melt ponds, brine, incubation experiments). Samples for dissolved inorganic nutrients (NO3 +NO2 , NO2 , PO4 , Si(OH)4, NH4 ) were analysed onboard during PS122 legs 1 to 3, with duplicate samples collected from CTD casts for later analysis of total dissolved nitrogen (TDN) and total dissolved phosphorus (TDP). From leg 4, all samples collected were stored frozen at -20°C for later analysis. Analyses of stored samples were carried out at the AWI Nutrient Facility between January and March 2021. Nutrient analyses onboard and on land were carried out using a Seal Analytical AA3 continuous flow autoanalyser, controlled by the AACE software version 7.09. Best practice procedures for the measurement of nutrients were adopted following GO-SHIP recommendations (Hydes et al., 2010; Becker et al., 2019). Descriptions of sample collection and handling can be found in the various cruise reports (Haas & Rabe, 2023; Kanzow & Damm, 2023; Rex & Metfies, 2023; Rex & Nicolaus, 2023; Rex & Shupe, 2023). Here we provide data from the water column, obtained from the analysis of discrete samples collected from CTD-Rosette casts from Polarstern (https://sensor.awi.de/?site=search&q=vessel:polarstern:ctd_sbe9plus_321) and Ocean City (https://sensor.awi.de/?site=search&q=vessel:polarstern:ctd_sbe9plus_935). Data from sea ice cores and special events are presented elsewhere. Data from sea ice cores and special events are presented elsewhere. For reference, here we included data from CTD-BTL files associated with nutrient samples. These data are presented by Tippenhauer et al. (2023) Polarstern CTD and Tippenhauer et al. (2023) Ocean City CTD.more » « less
-
Samples for the analysis of dissolved nutrients were collected during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) from the water column, sea ice cores and from special events/locations (e.g., leads, melt ponds, brine, incubation experiments). Samples for dissolved inorganic nutrients (NO3 +NO2 , NO2 , PO4 , Si(OH)4, NH4 ) were analysed onboard during PS122 legs 1 to 3, with duplicate samples collected from CTD casts for later analysis of total dissolved nitrogen (TDN) and total dissolved phosphorus (TDP). From leg 4, all samples collected were stored frozen at -20°C for later analysis. Analyses of stored samples were carried out at the AWI Nutrient Facility between January and March 2021. Nutrient analyses onboard and on land were carried out using a Seal Analytical AA3 continuous flow autoanalyser, controlled by the AACE software version 7.09. Best practice procedures for the measurement of nutrients were adopted following GO-SHIP recommendations (Hydes et al., 2010; Becker et al., 2019). Descriptions of sample collection and handling can be found in the various cruise reports (Haas & Rabe, 2023; Kanzow & Damm, 2023; Rex & Metfies, 2023; Rex & Nicolaus, 2023; Rex & Shupe, 2023). Here we provide data from the water column, obtained from the analysis of discrete samples collected from CTD-Rosette casts from Polarstern (https://sensor.awi.de/?site=search&q=vessel:polarstern:ctd_sbe9plus_321) and Ocean City (https://sensor.awi.de/?site=search&q=vessel:polarstern:ctd_sbe9plus_935). Data from sea ice cores and special events are presented elsewhere. Data from sea ice cores and special events are presented elsewhere. For reference, here we included data from CTD-BTL files associated with nutrient samples. These data are presented by Tippenhauer et al. (2023) Polarstern CTD and Tippenhauer et al. (2023) Ocean City CTD.more » « less
An official website of the United States government
