EVSC30006 Lecture Notes - Lecture 12: Habitat, Species Richness
LECTURE 12: URBANISATION & MARINE ENVIRONMENTS
RESTORATION
• Restoration: process of re-establishing, following a degradation by human activities, a sustainable habitat or
ecosystem with a natural, healthy structure & functioning
ECOLOGICAL ENGINEERING
Hard
• Many small-scale studies globally, need large scale adoption – increased understanding of what works well
• Seawalls: vertical orientation reduces area which can be colonised (only get tidal range), no microhabitats
• Ecologically friendly concrete: textures and holes added to provide microhabitat
o Results: positive effects on invertebrates & fish, ratio of invasive species lower, bioprotection – barnacles hold
structure together & reduce thermal stress = increased longevity of structure
• Rock Pools: different styles, high species richness
• Seeding: tiles seeded with local species of shellfish – higher rate of survival in crevices
Soft
• Can be used for coastal defence – sediment stabilisation & accretion, or help deposition & wave attenuation
• Can be as effective as submerged breakwaters
• Oyster Reef Restoration: different methods ranging from natural to artificial
o Increase biodiversity, provide fisheries & coastal defence
• Saltmarshes restored using planting: fared better than artificial structures during Hurricane Irene
o Used in conjunction with oyster reefs – hybrid approach
Positives
Negatives
• Ongoing benefits
• Ecosystems get stronger
with time
• Potential to self-recover
• Need to develop best practices
• Variable success
• Can be slow to establish
• Few data on cost-benefits
Hybrid
• Mangroves in concrete pots: pots facilitated survival in high energy conditions & provide wave attenuation while
mangroves grow
• No measurements of coastal defence
• Positives: capitalise benefit of natural & artificial, allows innovation, used in spaces where cannot fit one approach
alone
• Negatives: few trials, little data
Ecological Engineering: design of sustainable ecosystems that integrate human society with its natural
environment for the benefit of both, along continuum from hard to soft material used
Oyster Restoration
• Effort to restore in Port Phillip Bay
• Collaboration between industry & community stakeholders
• Little success, had to grow the oysters out of site, then translocate when they had established
• Shell recycling program: made a reef from recycled shells and rock to provide habitat for the oysters
Document Summary
Restoration: process of re-establishing, following a degradation by human activities, a sustainable habitat or ecosystem with a natural, healthy structure & functioning. Effort to restore in port phillip bay: collaboration between industry & community stakeholders. Little success, had to grow the oysters out of site, then translocate when they had established. Shell recycling program: made a reef from recycled shells and rock to provide habitat for the oysters. Ecological engineering: design of sustainable ecosystems that integrate human society with its natural environment for the benefit of both, along continuum from hard to soft material used. Hard: many small-scale studies globally, need large scale adoption increased understanding of what works well. Seawalls: vertical orientation reduces area which can be colonised (only get tidal range), no microhabitats.