MBSS Site Summary for: MPAX-102-R-2007

Site Photos

Field photo showing stream conditions at site MPAX-102-R-2007-1 (Opens in a new window) Field photo showing stream conditions at site MPAX-102-R-2007-2 (Opens in a new window)

Located on Middle Patuxent River UT2 in the Middle Patuxent River watershed, 8-digit code: 02131106.
This stream was visited in the spring on 4/18/2007 and again in the summer on 8/24/2007.

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 - 1.0 / 5.0
Benthic IBI Poor - 2.7 / 5.0

Land Use

Land use can provide important information for determining stream health.
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Catchment area 53 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 16.1 %
Agricultural Land Use 83.5 %
Forested Land Use 0 %


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

Physical Stream Habitat
Instream Habitat 4/20 (Poor)
Epifaunal Substrate 6/20 (Marginal)
Velocity/Depth Diversity 2/20 (Poor)
Pool Quality
Pool Extent = 74 meters 		3/20 (Poor)
Riffle Quality
Riffle Extent = 1 meters 		1/20 (Poor)
Shading 95 %
Embeddedness 70 %
The embeddedness, a measure of silt on the stream bottom, was 70%. This is relatively high, and may exclude some biota.
Several measures of instream habitat were considered 'Poor' at this location.


Stream Water Quality:
Water temperature 19.1 ° C
Dissolved oxygen (DO) 3.7 mg/L
Dissolved oxygen levels measured in the stream were very low (3.7 mg/L). Many fishes and other aquatic animals cannot tolerate low levels of oxygen in the water.
pH (lab) 6.9
Conductivity 453 µmho/cm
Alkalinity
(acid neutralizing capacity) 		360.3 µeq/L
Dissolved organic carbon (DOC) 1.5675 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 1 fish species were collected.
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Common name Count
No Fish Observed 0
Biologists sampling fish communities.
Electrofishing to sample fish communities.

Amphibians and Reptiles:
Northern Two-Lined Salamander

Crayfish:
No crayfish noted.

Exotic Plants:
Japanese Honeysuckle
Japanese Stiltgrass
Mile-A-Minute
Multiflora Rose
Oriental Bittersweet
 

Benthic Macroinvertebrates:
Sensitive taxa: Green, Tolerant: Red, Intermediate: Gold.
Genus/Family Common Name Count
Parametriocnemus Non-Biting Midges 35
Polypedilum Non-Biting Midges 9
Orthocladius Non-Biting Midges 9
Amphinemura Spring Stonefly 8
Tanytarsus Non-Biting Midges 6
Stegopterna Black Fly 6
Diplectrona Net-Spinning Caddisfly 5
Pseudolimnophila Crane Fly 4
Chrysops Deerfly 4
Musculium Fingernail Clam 3
Thienemannimyia group Non-Biting Midges 3
Rhyacophila Free-Living Caddisfly 2
Psilotreta Mortarjoint Casemaker Caddisfly 2
Rheosmittia Non-Biting Midges 1
Tipula Crane Fly 1
Diamesinae Non-Biting Midges 1
Microtendipes Non-Biting Midges 1
Ptilostomis Giant Casemaker Caddisfly 1
Diamesa Bloodworm 1
Ceratopogon Biting Midge 1
Ceratopogonidae Biting Midge 1
Simulium Black Fly 1
Limnephilidae Northern Casemaker Caddisfly 1
Hydroporus Water Beetle 1
Lumbriculidae 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.