Plant and Environmental Restoration Exam 2

three part definition of wetland

1. vegetated aquatic ecosystem with prolonged saturated soil conditions

2. saturation is dominant factor in determining plant and animal species

3. vegetation adapted to life with saturation

importance of wetlands

flood control and water quality

flood control by wetlands

slow moving water storage, dispersion, slow infiltration to recharge groundwater evapotranspiration

water quality monitoring of wetlands

nutrient filtering, conversion, sequestration, recovery

vegetation in wetlands

usually hydrophytic, tolerate water

not most reliable indicator of a wetland

obligate wetland vegetation (OBL)

almost always is a hydrophyte

facultative wetland vegetation (FACW)

usually a hydrophyte but occasionally found in uplands

facultative vegetation (FAC)

commonly occurs as either a hydrophyte or nonhydrophyte

facultative upland vegetation (FACU)

occasionally is a hydrophyte but usually occurs in the uplands

upland vegetation (UPL)

rarely is a hydrophyte, almost always in uplands

hydric soil

soil that developed under limited O2 conditions

characteristics of hydric soil

high organic content, thick layer of decomposing plant material, mineral soil is gleyed, smells like rotten eggs (reduced sulfur)

hydrology of a wetland

periodic flooding, saturation within 25 cm of the soil surface

restoring hydrology of wetlands

plug ditches and drainage and breaching levees

microtopography

creating small mounds and kettles to create diversity in a small area

common wetland graminoids

sedges, rushes, bulrushes, cattails, rice cutgrass, fowl mannagrass

common wetland forbs

smartweed, aster

common wetland shrubs

buttonbush, elderberry, hawthorn, red-osier dogwood, spicebush, willow

common wetland trees

ash, bald cypress, river birch, sugarberry, hackberry, sycamore, willow, black

drumheller slough habitat restoration

restoration proposal in sacremento valley to restore connectivity of riparian, improve habitat, and improve ecological function

problem in slough restoration

loss of riparian vegetation and species, reduced ecological services, contains NIS

active restoration

jump-start or reset successional process, eradicate weeds, replant native species, irrigate, modify land to control hydrology, erosion control

passive restoration

stopping or removing human activities, reform topography to natural state, allow natural processes

compare active vs. passive restoration

passive is cheaper/slower but has high risk of failure due to invasives

specific goals of slough restoration

135 acres of riparian forest

restore 2000 feet of natives on bank

slow soil erosion

native grasses to control NIS

plant recruitment

natural establishment of new plant units by seed or propogation

baseflow

The part of the river's discharge that is provided by groundwater seeping into the bed of the river

toe (stream cross section)

bank area from baseflow level to the ordinary high-water level

active erosion

scarp

steep bank above the toe in a stream

very little vegetation

Bankfull level

level at which water spills over banks

thalweg

deepest part of the channel, fastest flow, outside the bend

meander bend point bar

gravel bar that forms on the inside of the meander bend due to deposition

riparian zone

land adjacent to rivers and streams affected by stream hydrology

gravel bedload

the natural load of gravel and sediment moving downstream

equilibrium should be reached between arrival of new gravel and displacement of existing gravel

bankfull flow

discharge at which natural channel maintenance is the most effective

two main aspects of stream channel restoration

1. proper stream channel geometry

2. bank stabilization

general goal of stream restoration

slow down water and decrease sediment loss

desired outcomes of stream restoration

1. slow release of source waters

2. robust vegetation along toe, banks, and floodplain

3. banks resist undercutting and erosion

main visual assessment parameters that are affected by plant life

channel condition, riparian zone, bank stability, barriers to fish movement, instream fish cover, canopy cover, manure presence

live stakes

live, rootable stem cuttings inserted into soil through erosion fabric

willows and poplars

Live fascines

long bundles of branch cuttings, protect bank toe

tree revetments

whole trees (not root ball) cabled together and anchored into the bank; butt end aims upstream

rock riprap

layer of course rock on bank surface

rock gabions

steel mesh cages filled with rocks, locally use chicken cage gabions

coconut fiber rolls

coconut husk fibers wound into a cylinder and bound with twine

rock vanes

lines of rocks that stick out from the bank and are angled upstream, used to deflect water to the center of the stream

wildryes, woodoats

used in shaded areas, floodplain, tree borders

Eastern gamagrass

used in the sun, robust, lower bank

switch grass, beaked panic grass

both in the sun, upperbank

river cane

robust, partial shade to sun

shrubs for stream stabilization

buttonbush, dogwood, elderberry, holly, spicebush, willow, coralberry, ninebark, ozark witchhazel, chokecherry, bushy st. johnswort, strawberry bush

trees for stream stabilization

boxelder, maple, sycamore, river birch, cottonwood, sugarberry, oak, redmulberry

forbs for stream stabilization

jerusalem artichoke, jewelweed

planting tips for stream restorations

harvest every 2 years, erosion fabrics hold soil well, dip roots in root gel to slow desiccation,

woody vs herbaceous plants in stream restoration

Woody plants protect the bank better; grasses can do well if perennial with robust root systems

advantages of herbaceous plants in stream restoration

better with low, easy slopes

trap sediment, more pools and undercuts for fish

advantages of woody plants in stream restoration

shading, increased infiltration, provide debris for fish habitat

stream

water flowing on earth

channel

land form which a relatively narrow body of water is situated

geomorphology

shape or form of the earth

fluvial geomorphology

study of how flows of fluids shape the ground

primary stream functions

transport water and sediment, habitat, water supply, recreation, power, waste disposal, aesthetics

stream discharge calculation

cross-section area (A) * Velocity

calculating cross section area of a stream

length across the water * average depth of the stream

stream order

a measure of the relative size of streams, 1 is the smallest

ephemeral stream

flows for a few hours after rain

intermittent stream

flows only during rainy season

perennial stream

flows year-round

straight stream

confined by valley walls, high gradient

meandering stream

not confined, low slope

braided stream

not confined, steeper slope, higher discharge

zone 1 of stream profile zones

zone of sediment collection

high gradient

zone 2 of stream profile zones

zone of sediment transfer

gentler slopes

zone 3 of stream profile zones

zone of sediment deposition

even elevation, mouth of stream

types of sediment in a stream

dissolved sediment, suspended sediment, and bedload

stream entrenchment

stream deeps and widens over time

lane's balance

sediment discharge and size vs stream slope and water quantity

hyporheic zone

zone of transition between areas of surface water flow and groundwater, important for refuge and chemical reactions

influent stream

"losing," water table is below the stream

effluent stream

"gaining" stream, water table is above the stream

soil bioengineering

Use of live, woody vegetative cuttings to resist washout and provide erosion protection

anchored cutting systems

cuttings arranged in layers or bundles, secured down or partially buried

examples of anchored cutting systems

brush mattresses, brush layers, fascines, reed roll

geotextile systems

woven fabric on banks can be seeded with grasses underneath

what is a healthy stream?

one whose interacting forces are in balance to maintain shape, diverse biological community, and high water quality

give an example of how a change in one factor changes other factors in stream degradation

if stream power increases, and channel complexity and roughness do not absorb the additional energy, the stream will erode the banks and bottom

why do streams benefit from high complexity and diversity of physical structure?

complex streams provide diverse habitat and roughness for slowing water flow

what are some common chemical pollutants?

oxygen consuming materials, N, P, organic wastes, metals

what is the benefit of flooding?

maintain floodplain biological community, relieve erosive force by slowing flow, maintain shape, introduce woody debris

what are the chemical features of a healthy stream?

high O2, optimum pH, low N, P, contaminants, low NH3, low biological demand and chemical oxygen demand

what are the physical features of a healthy stream?

complexity to slow water, geometry for bankfull flow, banks resist scouring, flooding opportunity, good level of baseflow (high infiltration)

what are the biological features of a healthy stream?

riparian plants protecting bank, shade water, provide habitat, few in-stream plants, diverse wildlife

What is observed when assessing channel condition?

channelization, downcutting, bank erosion

What is observed when assessing the riparian zone?

width of natural vegetation zone, native vs nonnative plants, functional/structural diversity

What is downcutting and what are the indicators?

downcutting is the deepening of the stream channel over time due to high velocity or high sediment load

benefits of riparian vegetation

reduce amount of pollutants in the runoff

control erosion

provide cooler microclimate for aquatic biota

dissipates energy during flood events

concentrated flow

overland flow of runoff in small channels more than a couple inches deep

four aspects of spacial structure

matrix, patch, corridor, mosaic

matrix

land cover that is dominant and interconnected over the majority of the land surface

patch

a nonlinear area that is different than the matrix and less abundant