Summary
Summary The Living Environment ENVS1017 Module 2
- Course
- Institution
Full detailed notes on all Module 2: The Coastal Environment content. - The course unit is ENVS1017, The Living Environment at Macquarie University
[Show more]
Seller
Follow
sarahblack
Reviews received
Content preview
MODULE 2: THE COASTAL ENVIRONEMNTLecture 9, Week 5
WETLANDS AND ESTUARIES
LECTURE OUTLINE:
• Importance of wetlands and estuaries
• Estuary zones
• Estuary classification
- Wave-dominated
- Tide-dominated
• Tidal zonation
• Estuary habitat
- Mangroves
- Salt marsh
• Estuary hydrodynamics
- Stratification and mixing
- Tidal range inside estuaries
- Tidal asymmetry
- Tidal prism and fishing times
CATCHMENT FRAMED APPROACHES TO ENVIRONMENTAL MANAGEMENT
• Treat catchments as integrated networks of flows and fluxes
• Treat causes not symptoms of problems in catchments
• Work within an ecosystem based or nature based approach
WETLANDS
• Wetlands = periodically or continuously inundated areas with shallow water and or
saturated soils
• Have plants and other biota that are adapted to wet conditions
• Occupy an intermediate position between terrestrial and fully aquatic ecosystems
• Fulfil important hydrological and biochemical functions
• Possess a diverse range of geomorphic and sedimentary features
• Support high biodiversity
ESTUARIES
• Estuaries = a semi-enclosed coastal body of water, with a free connection to the open sea,
and within which sea water is diluted with freshwater from land drainage
• In other words: the seaward limit of a drowned valley which receives sediment from both
river and marine sources and their morphology is influenced by tide, wave and river
processes
1
,WHY ARE ESTUARIES IMPORTANT?
• Provide a range of habitats: mud flats, sand flats, salt marsh, mangroves, wetlands
• Estuarine habitats (e.g. salt marsh) can filter water of pollutants
• Important nurseries (e.g. for fish and shellfish, provide protection)
• Buffer zones: shore stabilisation and coastal protection e.g. from storm surges
• Support lots of human populations
• Hugely important for economies, recreations and culture
ADDITIONAL PROBLEMS FOR ESTUARIES
• Estuarine habitat loss due to historic draining and infilling e.g. to farmland
• Often low-lying developments e.g. Tuggerah Lakes, Central coast
• Eutrophication due to high nutrient loads
• Pathogens and pollution e.g. from runoff
• Decline of sea grass, salt marsh and mangroves
- In NZ mangrove spread is occurring
HEALTH OF AUSTRALIAN ESTURIES
ESTUARY ZONATION
• Most estuaries have 3 main zones:
- Inner river dominated
- Central mixed
- Outer marine dominated (waves and tides)
• Different parts of the estuary have different energy regimes
2
,ESTUARY ZONATION
ESTUARY CLASSIFICATION
• The physical properties of estuaries depends on: geology, waves and tides, and amount of
available sediment
• Classification considering morphology and dominant processes
- Two main types are:
o Wave dominated estuaries
o Tide dominated estuaries
ESTUARY CLASSIFICATION: WAVE DOMINATED ESTUARY
• Coastal bedrock embayment that has been partially infilled by sediment derived from both
the catchment and marine sources, in which waves are the dominant force shaping the
gross geomorphology
- E.g. Tuggerah lakes (NSW), Broke Inlet (WA)
3
, WAVE DOMINATED ESTUARY
• Energy distribution
- In outer zone waves break and only a little tidal energy comes in through the inlet
• Plan view of morphology
- Barrier system and tidal inlet
- Ebb and flood tidal delta
• Profile of sediments
- Coarser sediments in outer and inner zones
- Note flood tidal and bay head deltas
- Fine sediments in central zone
ESTUARY CLASSIFICATION: TIDE DOMINATED ESTUARY
• Landward tapering funnel shaped valley, bounded by various intertidal sedimentary
environments such as intertidal flats, mangroves, saltmarshes and saltflats
- E.g. Fitzroy river (Qld), Victoria river (NT)
4
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller sarahblack. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $8.49. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
77254 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now