Historical News
Week of April 8 - 14, 2024
Fixed Site Network
Phillipsdale Landing
Overall, water quality at Phillipsdale Landing was good this week. Weather conditions included sporadic rain events, with 1.0 inches of precipitation recorded at T.F. Green. The Blackstone River flow increased during the 12th and 13th and remained above the 19-year daily median for the week. Surface salinity this week averaged 2.4 ppt and ranged from 0.2 ppt to 7.5 ppt. At the bottom, salinity averaged 8.6 ppt and ranged from 0.2 ppt to 26.4 ppt. Temperatures increased this week, averaging 10.5°C at the surface and 9.8°C bottom. Surface temperatures ranged from 6.5°C to 12.3°C, while bottom temperatures ranged from 5.9°C to 12.5°C.
Dissolved oxygen (DO) at Phillipsdale Landing remained above the hypoxia threshold (i.e., DO >2.9 mg/L) throughout the week. Surface DO averaged 11.5 mg/L and ranged 10.0 – 12.7 mg/L. Bottom DO concentrations averaged 11.0 mg/L and ranged from 9.1 mg/L to 12.6 mg/L. Chlorophyll concentrations remained low, averaging 2.3 ug/L at the surface and 4.2 ug/L at the bottom. Maximum chlorophyll at the surface reached 15.1 ug/L on the morning of April 12th. Please note that tidal fluctuations and Blackstone River flows greatly influence water column salinity, temperature, and DO at this location. Also, please note that isolated portions of suspect chlorophyll data from April 8th to the 11th were excluded from the summary.
Bullock Reach
The Bullock Reach Buoy remains out of the water for the winter. EM will coordinate with RIDEM to redeploy the buoy in late spring.
Week of April 1 - 7, 2024
Fixed Site Network
Phillipsdale Landing
The Phillipsdale Landing sondes have been deployed for the season since April 2nd, 2024. Overall, water quality at Phillipsdale Landing was good this week. Weather conditions were wet this week, with a total of 2.22 inches recorded at T.F. Green, and the majority of rainfall occurring between the 2nd and 4th. The Blackstone River flow increased during the 4th and remained above the 19-year daily median for the week. Salinity at the surface averaged 1.8 ppt and ranged from 0.2 ppt to 5.7 ppt. At the bottom, salinity averaged 9.2 ppt and ranged from 0.2 ppt to 27.6 ppt. Temperatures this week averaged 7.4°C at the surface and 6.7°C at the bottom. Surface temperatures ranged from 5.8°C to 9.9°C, while bottom temperatures ranged from 5.6°C to 8.9°C.
Dissolved oxygen (DO) at Phillipsdale Landing remained above the hypoxia threshold (i.e., DO >2.9 mg/L) throughout the week. Surface DO averaged 12.2 mg/L and ranged from 11.0-13.5 mg/L. Bottom water DO concentration averaged 11.6 mg/L and ranged from 9.2 mg/L to 13.6 mg/L. Chlorophyll remained low, averaging 1.6 ug/L at the surface and 3.1 ug/L at the bottom. Maximum surface chlorophyll readings reached 4.3 ug/L, recorded on the morning of April 4th. Please note that tidal fluctuations and Blackstone River flows greatly influence water column salinity, temperature, and DO at this location. Also, please note that an early portion of the bottom data is not included in the summary above due to bottom deployment getting into position.
Bullock Reach
The Bullock Reach Buoy remains out of the water for the winter. EM will coordinate with RIDEM to redeploy the buoy in late spring.
May 20, 2024
R/V Monitor's Blog
Today a new MET Sensor Assembly was installed on the recently deployed Bullocks Reach Buoy. The assembly includes a weather station that can monitor wind speed, humidity, air pressure, and temperature. The buoy was deployed on May 14th and staff have been diligently working to get the buoy up and running for the 2024 Fixed Site Monitoring Season.
May 1, 2024
Phytoplankton Sampling
Phytoplankton samples were collected on May 1, 2024 at Bullock Reach and analyzed in the laboratory shortly after collection. It was a cold and breeze day on Narragansett Bay with cloudy conditions. The qualitative tow net sample had a long filtration time, and the filtrate was a reddish brown and slightly cloudy.
The analysis of the quantitative whole water sample revealed a total of 4,006,000 cells per Liter. The micro flagellates were found at 24,000 cells/L. The most predominant phytoplankton genus was Skeletonema spp. at 1,646,000 cells/L. Other representative genera include Thalassiosira spp., Leptocylindrus spp., and Chaetoceros spp. This week's featured image is Eucampia spp. (200x phase contrast), a type of diatomic phytoplankton that is often found in the North Atlantic Ocean. This genus is often found in a curved form and in helical chains. This diatom is yellow-brown in color with numerous green chloroplasts.
April 16, 2024
Phytoplankton Sampling
Phytoplankton samples were collected on April 16, 2024 at Bullock Reach and analyzed in the laboratory shortly after collection. It was a sunny and calm day on Narragansett Bay. Some lions mane jellyfish were detected. The qualitative tow net sample had a fast filtration time, and the filtrate was a clear yellow-brown color.
The analysis of the quantitative whole water sample revealed a total of 1,038,000 cells per Liter. The micro flagellates were found at 32,000 cells/L. The most predominant phytoplankton genus was Skeletonema spp. at 529,000 cells/L. Other representative genera include Leptocylindrus spp. and Chaetoceros spp. Actinoptychus spp. is a type of photosynthetic phytoplankton belonging to the centric diatom group. It is found in Narragansett Bay and widely distributed in spring and fall. It is identified by six radial sectors. The raised sectors can appear to look like a hazard sign, as seen in this 200x phase-contrast image.
