Folder Water Quality

pdf MTU_LCWC Water Quality Poster - 2014

Impact of Nutrient Loading and Eurasian Watermilfoil on Phytoplankton Communities Among Channels of the Les Cheneaux Islands, Lake Huron

Authors: Jade E. Ortiz1 , Amy M. Marcarelli1 , Gary L. Fahnenstiel1 , Rob A. Smith2

Author Affiliation: 1 Michigan Technological University, 2Les Cheneaux Watershed Council

Journal: Unpublished; Cooperative Project between LCWC & MTU; 2014

Abstract: Water quality is a concern in channels of the Les Cheneaux Islands, but little is known about phytoplankton communities, which form the base of the pelagic food web.

This report provides a basis for understanding primary producer responses to nutrient loading and Eurasian watermilfoil (Myriophyllum spicatum) management efforts in the waterways of the Les Cheneaux Islands.

pdf Phosphorus and Phytoplankton Dynamics in the Les Cheneaux Islands

Phosphorus and Phytoplankton Dynamics in the Les Cheneaux Islands during a Rapid Rise in Lake Huron Water Level

Authors: R.A. Smith

Author Affiliation: LCWC

Journal: LCWC Report; April 2016

Abstract: The LCWC studies nutrients in the water, primarily phosphorus, and the density of free-floating algae, phytoplankton, to get an idea of what the season’s weed growth might be like. Rooted aquatic weeds like Eurasian watermilfoil get most of their nutrients from the bottom sediments and algae get their nutrient directly from the water.

From 2013 to the end of 2015 we experienced a 37 inch rise in lake levels. An unprecedented lake rise for a two year period, that resulted in a 30% dilution rate. What effect does that amount of dilution have on the weed growth, phytoplankton growth and availability of nutrients? That is what this paper addresses.

pdf Rapid decline of phytoplankton in the Les Cheneaux Islands during a five-year period

Rapid decline of phytoplankton in the Les Cheneaux Islands during a five-year period.

Authors: R.A. Smith

Author Affiliation: LCWC

Journal: LCWC Report; April 2018

Abstract:

The balance between plankton and rooted aquatic plants is critical to a healthy aquatic ecosystem. Moreover, plankton species and population densities are important to the aquatic food web. Estimates of phytoplankton (free-floating algae) density for this study were made by measuring photosynthetic chlorophyll which was chemically extracted from phytoplankton contained in water samples collected monthly throughout Les Cheneaux during a five month period each year. Resulting chlorophyll concentrations, in this case Chlorophyll-a, were used to estimate phytoplankton population densities throughout the study. Following a 2013 peak concentration in Chlorophyll-a (Chl-a) (1) recorded from twelve different sites throughout LCI, a steady, annual decline in Chl-a was observed through 2017.

pdf Trophic History of the Les Cheneaux Waters, 2001-2012

Trophic History of Les Cheneaux Waters: 2001-2012

Authors: R. A. Smith

Author Affiliation: LCWC

Journal: LCWC Report; January 13, 2013

Abstract: Factors that contribute to the growth of aquatic plants and affect recreational water quality have been studied by the Les Cheneaux Watershed Council and the Les Cheneaux Islands Association since 2001. During this survey period the recreational water quality has been classified as excellent according to limnology, or water scientist, criteria. The trophic state, or the potential of nutrients to support algal or plankton biomass, has remained essentially the same between 2001 and 2012.

pdf Water Chemistry Data for 2018

Results from Island Wide Water Monitoring, Summer 2018

 

Authors: R.A. Smith

Author Affiliation: LCWC

Journal: LCWC Report; April 2019

Abstract:

Ratings of 2018 water samples fell within expected nutrient ranges for the inner and outer island zones of the Les Cheneaux Islands and reflected high quality water for recreational purposes as has been the case since this type survey began in 2001. Analytical values for all test sites were within range of samples quantified by the Univ Mich Biological Station during the previous five seasons. The relationship of three variables: Total Phosphorus, Soluble Reactive Phosphorus and Chlorophyll-a was different than expected in 2018. Samples from the same test sites will be compared in 2019 to determine if 2018 result were an exception to past findings or an indication of a new
trend. Thanks to those who helped with sample collections during the season: Scott Myers, Lynn Wolters, John Bentley, Neil Williams and Mike Jellison.

pdf WQ5 Multi-year TP SRP Chl-a Ratios for LCI

Author: R.A. Smith

Author Affiliation: LCWC

Journal: Unpublished Report

 

Abstract

A primary nutrient for algae and weed growth has remained within a limited range during the past seven years.

Abstract: Three variables monitored during annual LCWC sampling of Les Cheneaux waters include Total Phosphorus (TP), Soluble Reactive Phosphorus (SRP) and Chlorophyll-a (Chl-a). Phosphorus is a growth limiting nutrient for phytoplankton (free-floating algae). Therefore, the availability of phosphorus is a primary factor in determining how much algae is present during any given year. SRP is a readily used form of phosphorus and can be quickly depleted during times of rapid algae growth. The relationship of these variables is an indicator of Les Cheneaux water chemistry stability. Observed values for these variables each year remain within the upper oligotrophic index signaling the nutrient fluctuation to be within normal Les Cheneaux variation. The stability of TP, SRP and Chl-a demonstrates the resiliency of our wetland ecology, even during years of continued increase in the Lake Huron level of 63 inches ( 160 cm) during this reporting period.
A follow-up paper will be developed to compare SRP/TP ratios of Les Cheneaux waters those of L Huron open waters to deter-mine if the seven-year rise in lake level impacted LCI ratios.

pdf WQ6 Results From Island Wide Monitoring, Trophic State Index (TSI) Analysis, Summer 2019

Author: R.A. Smiith

Author Affiliation: LCWC

Journal: Unpublished Report

 

Abstract

Les Cheneaux waters remain of a highly desirable quality for recreational use.

Ratings of 2019 water samples fell within expected trophic (nutrient) ranges for inner and outer island zones of the Les Cheneaux Islands. Variables quantified for Les Cheneaux water samples were: Total Phosphorus (TP), Soluble Reactive Phosphorus (SRP) and Chlorophyll-a (Chl-a).
TP and SRP values were found to be about equal in concentration. Chlorophyll-a was used as an indirect measure of phytoplankton concentration. As Chl-a values increase the SRP is metabolized and, therefore, decreased. Seasonal 2019 temperatures ranged from an average of 10.5 C (51 F) for the inner island zones to 16.5 C (62 F) for the outer island zones. Water clarity remained high to a point that the Secchi disk could be read when lying on the bottom at sites 2, 4a,8 and 9 where the depth ranged from 10ft to 45ft.

pdf WQ6A Results From Island Wide Water Monitoring, Trophic State Index (TSI), 2019, Abridged

Author: R. A. Smith

Author Affiliation: LCWC

Journal: Unpublished Report

 

Abstract

Les Cheneaux waters remain of a highly desirable quality for recreational use.

Ratings of 2019 water samples fell within expected trophic (nutrient) ranges for inner and outer island zones of the Les Cheneaux Islands. Variables quantified for Les Cheneaux water samples were: Total Phosphorus (TP), Soluble Reactive Phosphorus (SRP) and Chlorophyll-a (Chl-a).
TP and SRP values were found to be about equal in concentration. Chlorophyll-a was used as an indirect measure of phytoplankton concentration. As Chl-a values increase the SRP is metabolized and, therefore, decreased. Seasonal 2019 temperatures ranged from an average of 10.5 C (51 F) for the inner island zones to 16.5 C (62 F) for the outer island zones. Water clarity remained high to a point that the Secchi disk could be read when lying on the bottom at sites 2, 4a,8 and 9 where the depth ranged from 10ft to 45ft.

pdf WQ7 April 2020 Update - Decreased Algae Density in Les Cheneaux Island Waters Attributed to Cooler Water Temperatures and Rising Lake Huron Levels

Author: R.A. Smith

Author Affiliation: LCWC

Journal: Unpublished Report April 2020

 

Abstract:

From 2013 through 2019 water levels in the Les Cheneaux Islands have risen 63 inches (160 cm). During the same period, aver- age water temperatures dropped 3.5o to 4.5 o Centigrade ( 8o Fahrenheit). It was expected that these shifts in conditions would result in a related downward shift in phosphorus concentrations that are monitored each summer as part of our water quality program. This was not the case, however. Phosphorus values appeared to change little. Neither did it make sense that, while phosphorus concentrations remained level, the algae population densities decreased. Phosphorus is a primary food source for algae and if the phosphorus levels remained level, then algae concentrations would have been expected to remain within a constant range as well. Algae populations measured were phytoplankton, the free-living plankton that are found dispersed in the water column. The following paper examines this apparent disconnect between the expected and the actual.

ACKNOWLEDGMENTS:

Sincere appreciation is expressed to several people involved during this lengthy study, they include:

  • Editors of this document: Bill Kurtz, Scott Myers and Ed
  • Sample analysis: Tim Veverica and staff at the Univ Mich Biol Station at Douglas
  • Sample collection: Scott Myers, Lynn Wolters, Neil Williams, Mark Clymer, Mike & Laurel Jellison, Fred and Joyce Moore, Barb Smith, Mary Baker, Dave Dunn.