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Didymosphenia geminata in the Upper Esopus Creek: Current Status, Variability, and Controlling Factors.

George SD, Baldigo BP - PLoS ONE (2015)

Bottom Line: Survey period and Portal (upstream or downstream) each significantly affected D. geminata cell density.We found that D. geminata did not reach nuisance levels or strongly affect the periphyton community.A number of abiotic factors including variable flows and moderate levels of phosphorous and suspended sediment may limit blooms of D. geminata in this watershed.

View Article: PubMed Central - PubMed

Affiliation: New York Water Science Center, U.S. Geological Survey, Troy, New York, United States of America.

ABSTRACT
In May of 2009, the bloom-forming diatom Didymosphenia geminata was first identified in the Upper Esopus Creek, a key tributary to the New York City water-supply and a popular recreational stream. The Upper Esopus receives supplemental flows from the Shandaken Portal, an underground aqueduct delivering waters from a nearby basin. The presence of D. geminata is a concern for the local economy, water supply, and aquatic ecosystem because nuisance blooms have been linked to degraded stream condition in other regions. Here we ascertain the extent and severity of the D. geminata invasion, determine the impact of supplemental flows from the Portal on D. geminata, and identify potential factors that may limit D. geminata in the watershed. Stream temperature, discharge, and water quality were characterized at select sites and periphyton samples were collected five times at 6 to 20 study sites between 2009 and 2010 to assess standing crop, diatom community structure, and density of D. geminata and all diatoms. Density of D. geminata ranged from 0-12 cells cm(-2) at tributary sites, 0-781 cells cm(-2) at sites upstream of the Portal, and 0-2,574 cells cm(-2) at sites downstream of the Portal. Survey period and Portal (upstream or downstream) each significantly affected D. geminata cell density. In general, D. geminata was most abundant during the November 2009 and June 2010 surveys and at sites immediately downstream of the Portal. We found that D. geminata did not reach nuisance levels or strongly affect the periphyton community. Similarly, companion studies showed that local macroinvertebrate and fish communities were generally unaffected. A number of abiotic factors including variable flows and moderate levels of phosphorous and suspended sediment may limit blooms of D. geminata in this watershed.

No MeSH data available.


Related in: MedlinePlus

Locations of periphyton sampling sites in the Upper Esopus Creek and tributaries, 2009–2010.
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pone.0130558.g001: Locations of periphyton sampling sites in the Upper Esopus Creek and tributaries, 2009–2010.

Mentions: The Upper Esopus Creek is located in the south central Catskill Mountain Region of southeastern New York (Fig 1). The Creek follows a 41.8 km semi-circular course from its headwaters at Winnisook Lake, around Panther Mountain, to its impoundment downstream of Boiceville, where it forms the Ashokan Reservoir. The watershed area of the Upper Esopus Creek is 497.3 km2 and drains some of the most rugged and mountainous terrain in the Catskills. Forested land comprises over 95% of the watershed and its surficial geology features lacustrine clay deposits that contribute suspended sediment to the system [27]. Turbidity and other potential water quality impairments are a major concern in this watershed because the Ashokan Reservoir provides close to 40% of New York City’s drinking water [28]. Nine major tributaries (Table 1) deliver waters to the Upper Esopus in addition to the Shandaken Portal, the terminus of an inter-basin aqueduct which diverts water from Schoharie Reservoir to its confluence with the Upper Esopus in Shandaken. Discharge from the Portal can increase natural flows on the Upper Esopus by a factor of two or greater and the supplemental flow usually has a moderating effect on ambient stream temperature (cooler in the summer, warmer in the winter) [29].


Didymosphenia geminata in the Upper Esopus Creek: Current Status, Variability, and Controlling Factors.

George SD, Baldigo BP - PLoS ONE (2015)

Locations of periphyton sampling sites in the Upper Esopus Creek and tributaries, 2009–2010.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4493098&req=5

pone.0130558.g001: Locations of periphyton sampling sites in the Upper Esopus Creek and tributaries, 2009–2010.
Mentions: The Upper Esopus Creek is located in the south central Catskill Mountain Region of southeastern New York (Fig 1). The Creek follows a 41.8 km semi-circular course from its headwaters at Winnisook Lake, around Panther Mountain, to its impoundment downstream of Boiceville, where it forms the Ashokan Reservoir. The watershed area of the Upper Esopus Creek is 497.3 km2 and drains some of the most rugged and mountainous terrain in the Catskills. Forested land comprises over 95% of the watershed and its surficial geology features lacustrine clay deposits that contribute suspended sediment to the system [27]. Turbidity and other potential water quality impairments are a major concern in this watershed because the Ashokan Reservoir provides close to 40% of New York City’s drinking water [28]. Nine major tributaries (Table 1) deliver waters to the Upper Esopus in addition to the Shandaken Portal, the terminus of an inter-basin aqueduct which diverts water from Schoharie Reservoir to its confluence with the Upper Esopus in Shandaken. Discharge from the Portal can increase natural flows on the Upper Esopus by a factor of two or greater and the supplemental flow usually has a moderating effect on ambient stream temperature (cooler in the summer, warmer in the winter) [29].

Bottom Line: Survey period and Portal (upstream or downstream) each significantly affected D. geminata cell density.We found that D. geminata did not reach nuisance levels or strongly affect the periphyton community.A number of abiotic factors including variable flows and moderate levels of phosphorous and suspended sediment may limit blooms of D. geminata in this watershed.

View Article: PubMed Central - PubMed

Affiliation: New York Water Science Center, U.S. Geological Survey, Troy, New York, United States of America.

ABSTRACT
In May of 2009, the bloom-forming diatom Didymosphenia geminata was first identified in the Upper Esopus Creek, a key tributary to the New York City water-supply and a popular recreational stream. The Upper Esopus receives supplemental flows from the Shandaken Portal, an underground aqueduct delivering waters from a nearby basin. The presence of D. geminata is a concern for the local economy, water supply, and aquatic ecosystem because nuisance blooms have been linked to degraded stream condition in other regions. Here we ascertain the extent and severity of the D. geminata invasion, determine the impact of supplemental flows from the Portal on D. geminata, and identify potential factors that may limit D. geminata in the watershed. Stream temperature, discharge, and water quality were characterized at select sites and periphyton samples were collected five times at 6 to 20 study sites between 2009 and 2010 to assess standing crop, diatom community structure, and density of D. geminata and all diatoms. Density of D. geminata ranged from 0-12 cells cm(-2) at tributary sites, 0-781 cells cm(-2) at sites upstream of the Portal, and 0-2,574 cells cm(-2) at sites downstream of the Portal. Survey period and Portal (upstream or downstream) each significantly affected D. geminata cell density. In general, D. geminata was most abundant during the November 2009 and June 2010 surveys and at sites immediately downstream of the Portal. We found that D. geminata did not reach nuisance levels or strongly affect the periphyton community. Similarly, companion studies showed that local macroinvertebrate and fish communities were generally unaffected. A number of abiotic factors including variable flows and moderate levels of phosphorous and suspended sediment may limit blooms of D. geminata in this watershed.

No MeSH data available.


Related in: MedlinePlus