MBSS Site Summary for: AA-N-190-101-97


Located on PATUXENT R UT2 in the Patuxent River middle watershed, 8-digit code: 02131102.
This stream was visited in the spring on 3/6/1997 and again in the summer on 6/2/1997.

Index of Biotic Integrity (IBI) Results:

An Index of Biotic Integrity (IBI) is a scientific tool used to identify and classify stream health. An IBI associates anthropogenic influences on a stream or with biological condition in the stream, and is formulated using data developed from biosurveys.
Details on the development and application of MBSS IBIs are in this document.
Fish IBI Poor - 1.3 / 5.0
Benthic IBI Poor - 1.0 / 5.0

Land Use

Land use can provide important information for determining stream health.
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Catchment area 231 acres Cows standing in a stream at a site with high agricultural land use. Cows survey the sampling procedure at this extreme example of a highly agriculturalized site.
Urban Land Use 18.3 %
Agricultural Land Use 46 %
Forested Land Use 36.5 %


Stream showing woody debris, logs, and rocky substrate.
An example of woody debris in a stream.

Physical Stream Habitat
Instream Habitat 8/20 (Marginal)
Epifaunal Substrate 11/20 (Suboptimal)
Velocity/Depth Diversity 11/20 (Suboptimal)
Pool Quality
Pool Extent = meters 		11/20 (Suboptimal)
Riffle Quality 11/20 (Suboptimal)
Shading 86 %
Embeddedness 35 %


Stream Water Quality:
Water temperature 15.5 ° C
Dissolved oxygen (DO) 8.4 mg/L
pH (lab) 6.69
Conductivity 214 µmho/cm
Alkalinity
(acid neutralizing capacity) 		380.2 µeq/L
Dissolved organic carbon (DOC) 4.7 mg/L

Biological Stream Condition:

Surveys of the organisms living within a stream can give indications of stream health. Species richness, or the number of different species present, as well as indicator species (species whose presence, absence or abundance can serve as a measure of environmental conditions) are informative for stream health. 		Close-up of a mayfly indicator species.

Fish Survey Results:
The following 3 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
Blacknose Dace 31
Eastern Mudminnow 21
American Eel 1
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
Eastern Box Turtle
Eastern Mud Salamander
Northern Green Frog
Northern Two-Lined Salamander

Crayfish:
No crayfish noted.

Exotic Plants:
No exotic plants noted.
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Orthocladiinae A Non-Biting Midges 51
Cricotopus/Orthocladius Midge 27
Diplocladius Non-Biting Midges 8
Parametriocnemus Non-Biting Midges 6
Rheotanytarsus Non-Biting Midges 2
Diamesa Bloodworm 2
Natarsia Non-Biting Midges 1
Crangonyx Amphipod 1
Naididae Aquatic Worm 1
Kick net sampling for macroinvertebrates.
Sampling with a kick net.

Information disclaimer: The information and data on this page is for guidance and general planning purposes only. It should not be used to make decisions on specific matters.