lower trophic level indices of biological integrity and their possible cbp uses
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Lower Trophic Level Indices of Biological Integrity and Their Possible CBP Uses. Presentation to the Monitoring and Assessment Subcommittee May 12, 2004 Meeting by Claire Buchanan and Jacqueline Johnson Interstate Commission on the Potomac River Basin. “Lower Trophic Levels”. - PowerPoint PPT PresentationTRANSCRIPT
Lower Trophic Level Indices of Biological Integrity
and Their Possible CBP Uses
Presentation to the Monitoring and Assessment Subcommittee
May 12, 2004 Meeting by
Claire Buchanan and Jacqueline JohnsonInterstate Commission on the Potomac River Basin
“Lower Trophic Levels”
Phytoplankton
Benthos
SAV Zooplankton
Source to Resource
SourceWater
Quality
LowerTrophicLevels
Resource
Biological Integrity• “the capability of supporting and
maintaining a balanced, integrated, adaptive community of organisms having a species composition, diversity, and functional organization comparable to that of the natural (minimally impaired) habitat...”
(Karr and Dudley 1981)
• Healthy biological communities are:– more resilient to natural and man-made disruptions – require minimal external support from management
Index Development Steps
• Assess Habitat• Select Metrics• Score Metrics• Score Index • Validate Index
SAV
• Restoration Goals – Not an IBI– May be used like an IBI– “Reference sites” derived from historic
data– Poor water clarity is major stressor
Benthos
Restoration Goals Led to B-IBI•Reference Site Criteria
- No highly developed watersheds, no known point source discharges, and no toxic pollutants
- Low total organic content in sediments- Bottom dissolved oxygen
All records >2 mg DO liter-1 90% records >3 mg DO liter-1 80% records >5 mg DO liter-1
Benthic IBIs• strongly reflect seasonal habitat conditions• communities “meeting goal”:
– high abundance and high diversity of taxa– pollution sensitive species dominate– diverse feeding guilds
IBI Classification Efficiencies (Summer)
Tidal Fresh 66%
Oligohaline 73%
Low Mesohaline 78%
High Mesohaline Sand
82%
High Mesohaline Mud 88%
Polyhaline Sand 97%
Polyhaline Mud 95%
— 5 meets goal— 3
— 1— 2.1— 2.7 marginal
degraded
severely degraded
IBI Scale
Phytoplankton
• Reference Criteria for Samples in All Seasons
– Low phosphorus (PO4)and
– Low nitrogen (DIN) and
– Relatively high light (Secchi depth)
Phytoplankton IBIs
IBI Classification Efficiencies
IBI Scale
5 — 4 3 2 1 —
goodfair-goodfairfair-poorpoor
----
• strongly reflect immediate water quality conditions• reference, or “good,” communities:
- no nuisance algal blooms - associated with high DO and good water clarity- often higher median biomass (consistent good supply)
Spring Summer
Tidal Fresh
69% 78%
Oligohaline
71% 76%
Mesohaline
75% 73%
Polyhaline 84% 81%
Zooplankton
• POLYHALINE Reference Criteria for Summer Samples
– Low phosphorus (PO4)and
– Low nitrogen (DIN) and
– Relatively high light (Secchi depth)
Same as phytoplankton
***
Zooplankton
MESOHALINE Reference Criteria for Summer Samples
• Phytoplankton reference habitat criteria aren’t very effective…
• low DIN and • low PO4 and • low chlorophyll a and • high diatom biomass and • low dinoflagellate biomass (CART analysis)
Zooplankton
IBI Scale
5 — 4 3 2 1 —
goodfair-goodfairfair-poorpoor
----
IBI Classification Efficiencies
Summer
Mesohaline
78%
Polyhaline 88%
• reflect water quality and algal food conditions
• reference, or “good,” communities:
– higher median abundance & biomass, esp. copepods
– more “blooms” (desirable for fish)
– greater diversity (more robust)
Food Availability
Index
Poor: < 5 / liter
Anadromous Fish Spawning & Nursery Areas
(Mesozooplankton liter-1)
Below Minimum: 5 to 15 / liter
Minimum: 15 to 25 / liter
Optimal: > 25 / liter
Upper Bay
PotomacPatuxent
Choptank
Rappahannock
York
James
Analysis Tools at Hand
• SAV Restoration Goals• Benthic Restoration Goals and
IBI• Phytoplankton IBI• Zooplankton IBI, FAI, Habitat
Index
1. Confirm Achievement of Designated Uses
DO, water clarity, and chlorophyll a criteria are protective of designated uses
Criteria attainment doesn’t guarantee achievement of designated uses
Designated Uses
Ex. Potomac Shallow Water Habitats
Water Clarity Criteria Attainment0% 100%
Dry Years Wet Years
SAV Goal
Ex. Potomac Deep Water Habitats
Dissolved Oxygen Criteria Attainment60%
100%
Dry Years Wet Years
3.6 2.1 2.4 3.0 2.1 2.6 1.9
2.4 - - 3.3 1.6 2.2 1.3
Benthic IBI
Ex. Potomac Open Water Habitats
2.0 1.9 2.4
1.8 2.2 2.8
Risk of Algal Blooms100% 0%
Dry Years Wet Years
Phytoplankton IBI
2. Components in Index of Ecosystem Integrity (IEI)
• Ecological Integrity – “sum of balanced, integrated, and
adaptive chemical, physical, and biological data can be equated with ecological integrity”
(Karr and Dudley 1981)
Jordan and Vaas 2000“An Index of ecosystem integrity for Northern Chesapeake Bay” Environmental Science and Policy 3:S59-S88
• DIN• PO4
• Secchi depth• Chlorophyll a• Bluegreen and dinoflagellate biomasses• Ratio of mesozooplankton to microzooplankton• Microzooplankton biomass• Benthic restoration goal values (pre-IBI index)• % DO observations <1 ppm in bottom waters or <5ppm
above pycnocline• % SAV Tier 1 goal achieved• Index of relative proportions of carnivores, planktivores
and benthivores for fish• Number of species in bottom trawl
3. Mechanism for Coupling WQ & Fisheries Models
SourceWater
Quality
LowerTrophicLevels
Resource
WatershedModel
3D WaterQuality Model
EcoPath/EcoSimModel
Model elements Phytoplanktonin common: SAV
BenthosZooplanktonOysters
4. Fisheries Ecosystem Planning
• Habitat, Habitat Requirements and Habitat Management (Element 3)– Assess habitat value using habitat requirements– Produce habitat suitability maps
• Indicators of Ecosystem Health and Biological Reference Points (Element 6)– Use data from long-term monitoring data sets– Evaluate usefulness of existing indicators– Develop a framework in which to use indicators
Summary of Possible CBP Uses
• Confirm Achievement of Designated Uses
• Develop Index of Ecosystem Health
• Provide a Mechanism to Couple WQ and Fisheries Models
• Fisheries Ecosystem Planning
Data Time Line
1970
1972
1974
1976
1978
1980
1982
1984
1986
1988
1990
1992
1994
1996
1998
2000
2002
2004
2006
MD_PPCBP_LTBMEPA_EMAP
B-RGIB-IBI_V1B-IBI_V2
CBP_PHYTOPHYTO_INDRGI-PHYTO
P-IBI
CBP_ZOOLSBHI
ZOO_INDRGI-ZOO
Z-IBI
VIMS_STUDYVIMS_STUDY
CB_STUDYMD_ONLYVA_ONLY
CBP_SAV_1CBP_SAV_2
TECH_SYN_V1TECH_SYN_V2
Benthic Programs
Phytoplankton Programs
Zooplankton Programs
First CB Agreement Start LR Data Management Program
Start Plankton QA Program
SAV PROGRAMS
IC SAV GOALS 1989, 1990 & 1993
Acknowledgements
the CBP monitoring programs, past and present
Supported by Interstate Commission on the Potomac River Basin & EPA Chesapeake Bay Program