Post on 13-Dec-2015
The Biological Condition Gradient and The Biological Condition Gradient and Tiered Aquatic Life Uses: Tiered Aquatic Life Uses:
With Applications in the State of MaineWith Applications in the State of Maine
United States Environmental Protection AgencyUnited States Environmental Protection Agency
Tiered Aquatic Life Uses Working GroupTiered Aquatic Life Uses Working Group
Susan P. DaviesSusan P. Davies Maine Department of Environmental ProtectionMaine Department of Environmental Protection
TALU: TALU: Tiered Aquatic Life UsesTiered Aquatic Life Uses
Stressor Gradient
Bio
Con
diti
on G
rad
ien
t
A Scientific Model
Class A/AA Class A/AA “ “as naturally occurs”as naturally occurs”
Class B Class B “support all indigenous “support all indigenous species; no species; no
detrimental change”detrimental change”
Class CClass C “support indigenous “support indigenous fish (salmonids); maintain fish (salmonids); maintain
structure and function”structure and function”
A Water Quality Standards framework
Eco
logi
cal C
ond
itio
n
Aquatic Life Use Workgroup: Conceptual Model (from Cairns 1993)
--- Historical ---
recorded condition
Increasing human disturbance
- - No disturbance - -
existing condition (hypothetical)
Natural
Degraded
1
2
3
4
5
6
- - Severe disturbance - -
TALU: TALU: Tiered Aquatic Life UsesTiered Aquatic Life Uses
Stressor Gradient
Bio
Con
diti
on G
rad
ien
t
A Scientific Model
The Scientific Model-
Stressor:Response
Concepts
Biological Responses Across the Stressor Gradient
RE
SP
ON
SE
ME
AS
UR
E
Stressor Gradient[Effect of Human Activity]
LOW HIGH
Highly
Tolerant
Taxa
DE
LT
An
om
alie
s
(
fish
)
Native Taxa
Intolerant Taxa
Courtesy of Chris Yoder, CABB
HIGH
LOW
Stressor Gradient
Bio
logi
cal C
ondi
tion
Biointegrity Indicators
Stressor Criterion
low
high
low high
Biointegrity Criterion
from Stevenson
TALU : A Scientific Model
Concept #1The Biological Condition
Gradient
Bio
logi
cal C
ond
itio
n
Increasing Effect of Disturbance[Stressor gradient]
Low High
1Native or natural condition
2 Minimal loss of species; some density changes may occur
3Some replacement of sensitive-rare species; functions fully maintained 4
Some sensitive species maintained; altered distributions; functions largely maintained
5
6
Tolerant species show increasing dominance; sensitive species are rare; functions altered Severe alteration of
structure and function
Natural
Degraded
Overview of 10 AttributesOverview of 10 Attributes Taxonomic composition and toleranceTaxonomic composition and tolerance
Attributes I-VAttributes I-V Sensitive-EndemicSensitive-Endemic through through TolerantTolerant
Non-native taxaNon-native taxa Attribute VIAttribute VI
Organism conditionOrganism condition Attribute VIIAttribute VII
Ecosystem functionEcosystem function Attribute VIIIAttribute VIII
Physical-biotic interactionsPhysical-biotic interactions Attributes IX-XAttributes IX-X
Tier 1 Tier 3 Tier 6
Attribute 1Historicallydocumented,sensitive,long-lived orregionallyendemic taxa
As predictedfor naturaloccurrenceexcept forglobalextinctions
Some may beabsent due toglobal extinction orlocal extirpation
Absent
Attribute IISensitive- raretaxa
As predictedfor naturaloccurrence,with at mostminorchangesfrom naturaldensities
Some loss, withreplacement byfunctionallyequivalentSensitive-ubiquitous taxa
Absent
TALU : A Scientific Model
Concept #2The Generalized Stressor
Gradient
Stressor Agent(s)
Habitat Structure
Biological Response
Flow Regime
Energy Source
Biotic Interactions
Water Quality & Toxicity
Biological Index or
metric
Stressor Metric
This model is an explicit statement of multiple causation
The Linkage From Stressor Effects to Ecosystem Response
STRESSORS STRESS/EXPOSURE RESPONSE
Relationship Land Classes and Relationship Land Classes and Stream Macroinvertebrates in MaineStream Macroinvertebrates in Maine
ag forest mix urbanLANDTYP
0
10
20
30
40
I19
Number of
Mayfly,
Stonefly,
and
Caddisfly
Genera
preliminary results based on 424 samples
n=57 n=150 n=119 n=98
Summary BCG-GSG Framework
• A conceptually simple framework for holding enormous, user-defined complexity
• Organizes and prioritizes research needs
• Enhances communication
TALU: TALU: Tiered Aquatic Life UsesTiered Aquatic Life Uses
Stressor Gradient
Bio
Con
diti
on G
rad
ien
t
A Scientific Model
Class A/AA Class A/AA “ “as naturally occurs”as naturally occurs”
Class B Class B “support all indigenous “support all indigenous species; no species; no
detrimental change”detrimental change”
Class CClass C “support indigenous “support indigenous fish (salmonids); maintain fish (salmonids); maintain
structure and function”structure and function”
A Water Quality Standards framework
Eco
logi
cal C
ond
itio
n
Pass-Fail Aquatic Life Use Scenarios for a Hypothetical State
--- Historical ---
Increasing human disturbance
- - No disturbance - -
Natural
Degraded
- - Severe disturbance - -
--- Severely Altered ---
PASS
FAIL
1
2
3One 303d Listing Threshold?
5
6
4
Bio
logi
cal C
ond
itio
n
Increasing Effect of Disturbance[Stressor gradient]
Low High
1Native or natural condition
2 Minimal loss of species; some density changes may occur
3Some replacement of sensitive-rare species; functions fully maintained 4
Some sensitive species maintained; altered distributions; functions largely maintained
5
6
Tolerant species show increasing dominance; sensitive species are rare; functions altered Severe alteration of
structure and function
Natural
DegradedNA
B
C
AA
A
MAINE TALU
Data Analysis and Use Attainment
• Biological data put into statistical model (30 variable linear discriminant model)
• Model output is an estimation of strength of association of a sample to four water quality
classes
Class AClass A Class BClass B Class CClass C NANA
Biological community:Biological community:
NaturalNatural DegradedDegraded
% OF LINEAR MILES
ClassClass AAAA = 6% = 6%
Class AClass A = 45% = 45%
Class BClass B = 47% = 47%
Class CClass C = 2% = 2%
Designated Aquatic Life Uses in Maine
Since 1990
Miles of upgrades= 1,440
Miles of downgrades= 5
Bio
logi
cal O
utc
ome
Reducing Discharges from Lincoln Pulp and Paper Company Reducing Discharges from Lincoln Pulp and Paper Company into Penobscot Riverinto Penobscot River
1972 1974 1976 1978 1980 1982 1984 1986 1988 1990 1992 1994 1996
A
B
C
NA
YearSecondary wastewater treatment in place
2,700
1,600
13,600
BOD5 load kg/day
A B C NARESULT
0.0
0.1
0.2
0.3
0.4
0.5
PE
R_
IMP
Relationship Between Impervious Surfaces and Water Quality Attainment in Maine
Impervious Surfaces
(Portion of Drainage)
Aquatic Life Use Attainment
~ 5%
~ 12%
preliminary results based on 424 samples
Maine TMDL Target Values Maine TMDL Target Values for % Impervious Coverfor % Impervious Cover
Class %IC-demonstrated
attainment
TMDL WLA MOS
AA<6%
Does not apply
A <6% <5% 1%
B <8% 7-10% 6-9% 1%
C <15% 10-15% 8-13% 2%
Engineered reductio
n in
effects of s
tormwater
Maine Classification AttainmentMaine Classification Attainment
Designated Use Class
Monitoring Result
Attains Class?
Next Step
A A Yes --
C B Yes Upgrade ?
A B No TMDL
B NA No TMDL
Maine Extensions of TALU: Other Waterbody and Criteria Types
• Wetland BCG- TALU– Targeted Stream/Wetland monitoring
• Marine-estuarine – tiered aquatic life standards applied in
aquaculture permitting
• Tiered Nutrient Criteria – Conceptual model: – tiered chemical limits PLUS tiered biological
response limits – algae, macroinvertebrates
Susan P. Davies, MDEP
11 22 33 44 55 66
BCG Tiers Communicate Condition
a b c d e fNatural Degraded
Acknowledgments
Maine DEP Biological Monitoring Program
Leon Tsomides, Jeanne DiFranco
Tom Danielson, David Courtemanch
National TALU Work Group and Steering Committee (including 23 States and Tribes)
Susan K. Jackson,
USEPA-HECD, Washington, DC