20.11.2013 17:05:00
11/14/13
Templates and Ecological Interactions
-helpful for managing stream ecosystems
Watersheds, Networks, Stream Hydrology
Channel formation and stream habitat
Chemical environment
Ecological interactions/biotic interactions
Indicators of Hydrologic Alteration
-magnitude of monthly water conditions
-magnitude and duration of extreme conditions
-timing of extreme conditions
-frequency and duration of increased and decreased pulses
Overflow components
-monthly low flows
-extreme low flows
-high flow pulses
-small floods
-large floods
Rivers with increased populations = increased ammonium b/c sewer
treatment chemical indices for stream assessments
(also nitrates and phosphorous)
Biotic indicies for stream assessment
=% contribution of dominant family
=EPI index
=FBI index
20.11.2013 17:05:00
11/18/13
Nonindigenous species in fluvial environments
Nonindigenous = not native in a particular area
Four types:
-localized and numerically rare
-widespread but rare
-localized but dominant
-widespread and dominant
‘ecological imperialism’ (people recreate new landscapes, ex. Westward
expansion, to be similar to where they came from, think their flora and
fauna is better)
Examples with rainbow/brown trout affecting stream dynamics (see slides)
-Zebra mussels example
-Saltceder tamarix
-native vegetation contributes less to allochthonous inputs than
saltceder
River Fisheries
11/20/2013 5:05:00 PM
What maintains productivity and biodiversity in rivers?
Floodplain Rivers:
 Amazon River near Manaus
 High level of complexity
o Low water: water in main channel, oxbow lakes, depression
lake
o High water: flat water across smaller channels
 Hudson River: Floodplain reduced
o Backwater areas greatly reduced since 1907
 Constrained river
o Reduce size of channels in anthropogenic areas
 Mississippi River near St. Louis
o Huge flood event in 1993
o Reclaimed floodplains
Flood-Pulse Concept
 Annual predictable pulse (flood) is major control on riverine
structure and function
o Not the typical idea that production comes from upstream,



predictable change as it moves downstream
Lateral exchanges between floodplain and main river channel that
gives nutrients
Pulses result in alteration of flooding and drainage of floodplain
(aquatic/terrestrial transition zone)
Most primary production in floodplain rather than main channel
o Input of sediments from floodwaters; nutrient release from
newly flooded soil
 Spurs spawning
o Large input of biomass of aquatic vegetation
 Young and adult fish disperse and feed, dissolved O2
permitting
o Consolidation of sediments; moist soil germination
 Regrowth of terrestrial vegetation after water recedes
Fish Reproduction in Floodplain Habitats: FPC flood pulse concept –
alternative to river continuum concept (focuses more on the floodplain,
disconnected from concept of movement of nutrients downstream)





Temperal degree overlap between warm T and flood
o Flood coming in in warm T in temperate environments
o High PP in this time of year
Predictability of flood
o Fish need to be able to time to the flood pulse to spawn in the
right time
Rate of rise and fall
o Slower is easier for fish to move with it
Duration of inundation
o Need a longer time of flood for fish to spawn and have a life
history strategy
Area of floodplain
o Larger floodplain=more habitats available for fish
Key Life History Attributes (fish population factors)
 Reproduction
 Growth
o Need food sources and organic material
 Survival
o What are the sources of mortality?
Reproduction
Small river spawning habitats: brook trout – North temperate habitat
 Use small rivers to spawn in reds
 Use upwelling ground water
o Deposit in late fall, eggs covered by ice in winter
 Avoid predators during spawning season
o Upwelling groundwater removes ammonia and waste and
fungi accumulating on eggs
o Provides constant T
Vegetation associated spawning: pirate perch
 Spring spawner
 Attach eggs to tree roots and vegetative banks
o Adhesive eggs
o Hide eggs away from predators
Channel catfish – South or tropics

Spawn in cavity formed by rocks, logs, or a hole in a lake or river
bank
Growth
Migrate to ocean or remain in coastal system? – Swedish stream
 How to accumulate enough E to grow large enough to allocate
energy to reproduction?
 Life history challenge: get enough E to reproduce
 Fish in small steams need to decide to go to ocean or larger river
system with more nutrients but more predation
Migratory and resident populations in coastal streams: costs of migration
 Migratory brown trout pops found closer to coast and at lower
altitude than year-round resident ones
o Less energy to migrate if you’re closer to the ocean coast
already
o Less time in low energy environment
o Migratory fish spend several years in ocean environment
 Recruitment of migratory brown trout pops declines at higher
altitudes, but not resident ones
o Migratory fish increase recruitment at locations
Banded kokopu
 Strong altitudinal pattern at watershed scale
 Reflecting:
o Migratory access
o Habitat type – forest cover
Migratory Life Cycles
 Diadromous: move between fresh and saltwater to complete lifecycle
o Anadromous: sea fish that reproduce in freshwater (salmon)
o Catadromous: freshwater fish that breed in the sea (eels)
American Shad: Alosa sapidissima
 Shade CatchPerUE: Delaware River
o Low catches per haul up until a spike in 1965
o Management to increase shad fisheries
 Reduction in fish harvest
o
o

East
o
o
o
 Then rise in 70s and 80s
 Fry stocking
 Improve fish passage
Present decline from 90s
Belief is that ocean conditions increased shad, not the actual
river qualities
coast American shad management
Harvest regulations
Fry stocking
Fish passage enhancement
o Recognition (through no management) of ocean condition
influences
Hypothesis: Physical stream environment determines ecological effect of
salmon
 Lots of wood debris and forested area on one side of the stream
channel
 Open and larger sediment in open watershed
 Gradient between heavy and light timber harvest
o Retention of fish carcasses increases with large wood volume
 Retains nutrients of stream
 Before salmon migrate into stream channels, you have
more PP (chlorophyll) in heavily harvested watershed
(more nutrients from landscape and light)
 After salmon enter in fall, opposite effects (less PP in
streams with heavily harvested watershed) because
they are stirring up the sediment and decreasing light
River Use and Dams
11/20/2013 5:05:00 PM
Cautionary Fish Tale
 Colorado Pike
o Really aggressive fish peopled liked to fish
o Large fish by 1967 that they were endangered
o Top predator that died
o Changed river to use water
American Experiment
 Population expansion in relation to hydro-geomorphic character of
ricer basins encountered

As population expanded west, encountered lots of rivers
o Rivers used for mills and use
 In Ohio: Flood plains
 In arid parts west: irrigation
 Pacific NW: power
 Locks, levies, dams used to interact with water
How much water does a river need?
 Varies
 Thinking about stuff that lives in rivers
 As variation increases, river health declines
Simplified contrast
 Rivers want to change flow through time
 Humans want rivers to not change through time
Dams and Demands
 Off land factors: fields, cities
 Most prominent in-channel mechanism for flow alteration
 Golden age of dams
 Many reasons to build dams, mostly recreation

o Many small dams out there
o Bigger dams used for hydropower, irrigation, flood control
Effects can be dramatic
o Before dam, Green River: driven by snowmelt
 Snows in winter, runs off in spring, low flow in summer
o After dam:
 Far fewer flood peaks, higher flows in summer
 Make sure water is always available

Disrupts millennia of evolution
Dam Impacts
 General Findings: some consistency despite regional differences
o High magnitude decreased
o Low magnitude increased
o Daily magnitude variance decreased
o But reversals and pulse count increased
o Timing expanded, seasoning is off
Flow Homogenization
 Regional scale differences in 1st half of 20th century were reduced in
dammed rivers but retained in undammed rivers
Global Issue
 Info on 292 large river systems
 Are the systems modified? (Fragmentation and storage capacity)
o Much of the world is red where people live
o Outside of remote systems, not many unaltered major
systems
o Productivity is higher for rivers with infrastructure (dams)
 Reservoirs

16.5 million dams globally
o 8000 cubic kilometers
Latin America
 47% projects are high impact
Flow-Ecology Relations
 Effects biota through:
o Habitat - space
o Evolved life history patterns
o Connectivity – movement place to place
Riparian Flow Ecology (out of channel)
 Variety of different pathways from infrastructure to diversity
reduced
o Get down to loss of adapted species or change in succession
(natural cycle)
An Option
 Help organisms out
o Blow up dams

ELOHA



Environmental Flows
o Want infrastructure and productivity, but also want species to
survive
o Quantity and quality and timing of water needed to sustain
aquatic ecosystems and services they contribute to human
well-being
 In-between natural and regulated
Blue box: river biology and dynamics
Red box: what people who live in watershed want
Green box: river science meets biology
o Adaptive adjustments!
Stream and River Restoration
11/20/2013 5:05:00 PM
History
 Not until early 1970s that legislation or stream restoration really
occured
o Nepa, clean water act, endangered species act
o Army corp undone under legislation
 More projects to restore streams than any other ecosystem besides
maybe wetlands
 Functions people wanted from streams were taken away by army
corp engineers, so lots of stream restoration
Categories of fluvial modification
 Channelization
o Flood control act straightened stream channels
 Levees
o Disconnect stream channel from flood plain
 Dams
o Retain water, reservoirs
 Removal of riparian vegetation
o Common in agricultural areas






Invasive species
Impermeable surfaces in watershed
Chemical discharge
o Sewage treatment plants
o Nutrient runoff
Diversions
o Smaller diversions from landform modification
Pipes (streams going underground)
Construction on floodplains
Synthesis of US river restoration efforts
 37000 river restoration projects reviewed
 most costly: land acquisition
 least costly: riparian management
 cumulative: 9.1 billion dollars
o projects were not evaluated afterwards for success
 least expensive projects were most used
Regional US river restoration efforts
 Upper Midwest: number of water quality and riparian management
much reduced than other areas
 Pacific nw: very few bank stabilization projects because less of an
agricultural region and highly erodible soils
Terms





Restoration: return to original undisturbed state
o Use a temporal/historic or another stream to restore to that
ideal
o Few projects really try to fully restore streams
Rehabilitation: restore or improve some aspects of a stream
ecosystem
Habitat enhancement: localized (eg fish structures)
Reclamation: return a stream reach to its previous habitat type, but
not restore all functions (eg levee removal)
Mitigation: compensate elsewhere for adverse effects
Common Rehabilitation
 Road rehabilitation
o Redwood national park
 Park was to see if place could be restored
o Recreate connectivity for fish
o Rehabilitation meant removing road and restoring landscape
and vegetation in high erodible soils
 Riparian Rehabilitation: silviculture
o Restore vegetation


o Remove invasives and reestablish vegetation due to grazing
or human disturbance
Fencing and Grazing
o Fence out animals from grazing
Floodplain rehab
o Connecting isolated habitats
o Levee breaching
o Channel reconstruction

o Creation of new floodplain habitat
 Removing berms
o Channelizing/Restoring Kissimmee River
 Cost $414 million
Dam removals
o 1990s very few
o 2000s more and more
o downsides: nutrients or contaminants in sediments
In stream habitat structures for fisheries enhancement





Log structures
Log jams (multiple logs)
Cover structures
Boulder structures
Brush bundles
In stream channel modification
 Rosgen
The Future of Running Waters
11/20/2013 5:05:00 PM
Identifying Key Drivers
 Humans are everywhere
o There are not many pristine ecosystems that haven’t been
impacted by human influence
o Ecologists: How to manage and sustain systems
 Need to improve ecosystems
 Ambiguous metrics – not like human health with good
metrics
What do we need to do?



Understand ecosystem drivers
Understand large-scale patterns
Understand long-term trends
Understand ecosystem drivers
Anthropogenic biomes – Erle Ellis
 Working in world with anthropogenic biomes, not classic biomes
 Humans control biodiversity and ecosystem processes as much as



climate
Classic biome maps do not represent state of environment
o Much of biome area does not exist (potential vegetation)
o Limited mention of urban and agriculture land use
Classic climate based biomes are not static
o Anthropogenic climate change is altering biome location and
composition
Biomes derived from global patterns of human interactions
Key Drivers
 Exploitation of biological resources
 Land use modification
 Alteration of biogeochemical cycles
 Alteration of physical processes
 Human influences on the movement and distribution of living
organisms
 Aggregation and accumulation of unique or rare compounds
Are key drivers anthropogenic?
 Chart of % of sediment from cultivated land
o Used cesium 137 tht was deposited on landscape from
nuclear testing in 1950s and 60s
o Sediments from clay glacier deposits have lower levels of
Ce137 than sediments from agricultural lands
Movement of Earth per Year – human driver
 Under natural conditions, most of earth moved by rivers is in west

o Young mountains
o Steep erodible landscapes
o Not much in eastern US
Current earth movement by mining, construction, etc
o See the opposite of earth movement
o Effects landscape greatly
Hydrological Changes in Arizona – human driver
 Blue lines are natural rivers before development


Turquoise lines: contour to parallel lines are canals
o Now irrigation and ground water pumping
o Summer time now has standing water and vegetation where
ephemeral streams used to be
Nitrogen cycling in urbanized desert ecosystem
o Sycamore Creek (undisturbed): short flow paths in landscape,
hyporheiic exchange, nitrogen cycling short
o Indian bend wash (urbanized): Nitrogen cycling under control
of humans: long flow paths – deep waters that are pumped
back up
 Fertilizers, deep waters pumped up
Understand large-scale patterns
Compared forested to non forested stream reach across many stream orders
 Forested wider than unforested streams
 Unforested had higher water velocity

Forested = rougher, more ammonium uptake, respiration, total
macroinvertebrates
Understand long-term trends
Mississippi river sediment discharge
 Sediment discharge is currently correlated to water discharge
 In early decades, succeeded the water discharge
Increased river alkalinization
 Upward trend in many eastern states

Increase in elevation and precipitation had positive relationship with
alkalinization
What is a stream and why does it mater?
 Legislation
Defining “waters of the US” is a matter of current political and constitutional
debate