stream restoration Flashcards
What can streams be an indicator of?
Watershed health
Why are streams a cheap way to deal with waste?
Runoff from septic/sewage systems + agriculture leads to eutropication–> excess nutrients
creates anoxic conditions because of anaerobic decomposition
how does BC logging contribute to erosion?
Removal of vegetation and CWD
removal of roots
compaction of soils
Why are fish a main target?
salmonidae habitats are extremely important to BC. Most viable commercial and recreational fisheries in canada
important component of the food web,
integral to first nations culture and and indicator species for healthy environments
WHat are some habitat requirements for salmonids?
1) rearing (feeding, growing, threat avoidance)
2)Spawning
3) Egg incubation
different species at different life stages prefer specific habitat units : pools riffles glides and cascades
examples of specific habitats?
Juvinile coho–>pools
Juvenile steelhead–> riffles
Junior dolly varden–> transition b/w pools riffles
How do you identify the most important habitat component to enhance?
try to identify the freshwater life stage that is most limiting to adult population growth
What are some stream restoration techniques
work must be done in work window (july-september) to minimize harm to fish
-creating engineered hydraulic and habitat complexity (LWD)
What does removing debris jams do?
increase stream flow to flush sediment wedges.
What are cross vanes? what do they do?
Also known as W-weirs and J-hook vanes
They reduce the velocity and energy near the stream bank through grade control and redirecting flow to the centre of the stream
What is a riparian zone?
Area of forest and stream interaction, essential for both healthy forest and stream ecosystems
can provide bank stability, shade, protection from flood events, and large woody debris make riparion zones essential for both aquatic and terrestrial organisms
What practice significantly alters riparian zones?
Logging.
What are some riparian restoration techniques?
Silviculture treatments aimed to enhance development of old growth attributes
-creat a coniferous-deciduous mixed zone
What are the 5 Riparian vegetation type classifications?
- brush sites, understocked with conifers
- Overstocked with conifers
- deciduous forest over top of conifer understory
- deciduous dominate forest with poor conifer understory
- old growth forests
What is an objective for RVT 1.
Increase long term woody debris and bank stability by increasing conifer component and rooting structure