Transcript Stream Dynamics I: Biological Significance of Degraded Water Quality Doug Novinger Missouri Department of Conservation [email protected] 573-882-9880

Stream Dynamics I:
Biological Significance of Degraded Water Quality
Doug Novinger
Missouri Department of Conservation
[email protected]
573-882-9880
Key Ecological Components of Stream Ecosystems
FLOW
REGIME
PHYSICAL
HABITAT
PRODUCTIVITY
WATER
QUALITY
BIODIVERSITY
FOOD WEB
DYNAMICS
ENERGY
SOURCES
Water quality – characteristics of water relevant to
supporting life: chemical state, suspended/dissolved
material
Flow regime – timing, rate, and amount of water moving
through the system
Physical habitat – the structural environment
Energy sources – nourishment providing the basis for
aquatic life
Food web dynamics – the complex transfer of energy via
ecological relationships among species
Productivity and biodiversity – abundance, complexity, and
persistence of aquatic life
FLOW
REGIME
PHYSICAL
HABITAT
WATER
QUALITY
PRODUCTIVITY
BIODIVERSITY
FOOD WEB
DYNAMICS
ENERGY
SOURCES
Large-scale impacts to water quality
Small-scale impacts
Temporal scale affects the biological
significance of degraded WQ
Fish spawning
Chemical
spill
Fertilizer / pesticide
Annual applications
Scale Matters
Spatial Scale
• geographic extent
• magnitude
• location
Temporal Scale
• duration
• timing/frequency
Key Ecological Components of Stream Ecosystems
FLOW
REGIME
PHYSICAL
HABITAT
PRODUCTIVITY
WATER
QUALITY
BIODIVERSITY
FOOD WEB
DYNAMICS
ENERGY
SOURCES
Negative Impacts to WQ
•Excess Sediment
•Excess Nutrients (N & P)
waste treatment
ag & urban runoff
•Temperature, DO, pH
extremes
•Agrochemicals
pesticides
herbicides
fertilizers
•Urban/Industrial chemicals
byproducts
pharmaceuticals
WATER
QUALITY
How does WQ
interact with
flow regime?
Transport:
frequency
timing
concentration
FLOW
REGIME
WATER
QUALITY
Ozark cavefish
Bristly cave crayfish
How does WQ
interact with
habitat?
PHYSICAL
HABITAT
Structural
composition
and complexity.
FLOW
REGIME
WATER
QUALITY
Large woody debris benefits aquatic communities
Credit D. Warren
Credit F. Marston
River chub
(eastern U.S.)
Credit C.E. Johnston
Hornyhead chub (MO)
Nest-building by longear sunfish
How does WQ
interact with
energy
sources?
PHYSICAL
HABITAT
Regulates types
of internal and
external sources
and rates of
production.
FLOW
REGIME
WATER
QUALITY
ENERGY
SOURCES
caddisfly
caddisfly in case
damselfly
mayfly
hellgrammite
stonefly
Aquatic insect larvae are highly specialized in
feeding anatomy and behavior.
Stream Size (order)
The River Continuum Concept
From Vannote et al. 1980
Relative Channel Width
How does WQ
interact with
food webs?
PHYSICAL
HABITAT
Regulates
complexity,
paths, and
rates of
energy flow.
FOOD WEB
DYNAMICS
FLOW
REGIME
WATER
QUALITY
ENERGY
SOURCES
A simple
food web
Food web dynamics
Hey, le’go!
Can’t you tell I’ve
been eating
contaminated
detritus??!
Biomagnification
Bioaccumulation
Key Ecological Components of Stream Ecosystems
FLOW
REGIME
PHYSICAL
HABITAT
PRODUCTIVITY
WATER
QUALITY
BIODIVERSITY
FOOD WEB
DYNAMICS
ENERGY
SOURCES
Loss of Productivity and Biodiversity leads
to the homogenization of aquatic species
communities:
• Replacement of species intolerant of
degradation with fewer tolerant species
• Replacement of native species with
exotic pioneer species
• Loss of ecosystem function