Riparian Ecology & Health Assessment Flashcards
define watershed?
is land that shares a common drainage area from which water is captured & stored within the soil and over time is released down slope; these include rangelands and riparian zones together
what are the 3 functions of a watershed?
- capturing water: determined by plant cover, species composition, litter, stubble heights, slope
- storing water: storage determined by organic matter, soil depth, texture, structure & field capacity
- releasing water: release: amount of water in soil, ppt. that exceeds infiltration rate; slow release is preferred
what are 5 factors of water quality?
- sedimentation: turbidity- reduced salmonid spawning grounds
- bacteria/protozoa: overland flow of fecal coliform, streptoccus E-choli
- nutrients (N, PO4): plant uptake, or enters water source-algae blooms- decomposition- reduced 02 levels
- water temperature: ground h20 cooled by earths stable temp before it enters water course. more effective in cooling that stream bank shading- cooler summer, warmer winter. fish have a narrow temp fluctuation window
- oxygen levels: cooler temps- can maintain higher 02 levels
explain management implications?
- in order to reduce surface runoff, management must increase perrolation and infiltration. this can be achieved by improved plant vegetative cover which will support improved water quality.
- proper management of our upland plant communities are critical for proper functioning riparian zones. the uplands and riparian zones together act as a primary and secondary water filter systems.
define riparian zones?
an area of land adjacent to water influenced by free water during some point in time during the year. usually represents the lowest position of a watershed.
explain riparian zones?
- are dynamic and always changing- disturbance is a natural function.
- challenge is to separate out natural change from that of anthropogenic disturbance.
- detailed and frequent monitoring of riparian zone vegetation acts as a precursor indicator of future water quality issues. the plant community will show signs of stress well before you are presented with water quality issues; you just have to be looking for the signs
what are 5 functions of riparian zones?
- dissipate energy: energy= water flow x slope -> proper functioning uplands. Factors: sinuosity, bank vegetation, rock & woody debris
- balance erosion & depositional forces: water flow, stream bank vegetation substrate
- sediment filer: stream banks during high flow benefit from tall vegetation- flattens over & protects soil. upper flood plain-shorter herbaceous layer will suffice to reduce overland flow
- nutrient filter: phosphate uptake by plants. nitrogen uptake & conversion to available & non-available forms, nitrification & ammonification ie) organic matter, soil organisms
- stream-bank shading & stability: maintains water temp in summer & winter, adds organic matter- shredders, grazers decomposers, soil-stabilization- holds banks together.
what are the 4 pre-inventory procedures- site selection?
- reach selection: critical area versus key area; 75m from anthropogenic disturbances such as; roads, culverts, fences etc..
- season: plant phenology and normal water flows; avoid spring run-off, - in growth phase june-sept. -normal water flow conditions. -avoid high spring run -offs
- length of reach: on small streams use 200m or 2 meandering cycles
- width of reach: A) Biological- riparian plant species composition. B) Physical- (2x bank-full depth @ horizontal intercept). - for best results, use them both in combination.
what are the 11 riparian health attributes?
- vegetative cover
- cover of weed species
- cover of disturbance caused vegetation
- wood establishment & regeneration
- utilization of preferred woody vegetation
- decadent or dead woody material
- streambank root mass protection
- human caused bare ground
- streambank stucture alteration
- reach compaction
- streambank channel incisement
explain vegetative cover?
of the flood plain & streambanks. not species specific!
explain cover of weed species?
% cover of prohibited & noxious weeds over the flood plain & stream banks (2 parts: cover & density)
explain cover of disturbance caused vegetation?
% cover of introduced and/or invader (includes undesirable natives) plant species over flood plain & stream bank
explain woody establishment & regeneration?
are the preferred tree & shrubs present on the site, well established & regenerating?
explain utilization of preferred woody vegetation?
a) % browsing of current annual growth (leaders) of preferred trees & shrubs
b) other use of woody vegetation: use from clearing, logging, mowing, cutting & beaver
explain decadent or dead woody material?
the amount of standing decadent & dead tree/shrub material
