What is Biodiversity? - Teaching Biology Project

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Loss of Biodiversity – the Cape
Town example
High School Workshop
25 May 2013
Patricia Holmes
Biodiversity Management Branch
Environmental Resource Management Department
What is biodiversity?
Convention on Biodiversity:
The abundance and distributions of and
interactions between genotypes,
species, communities, ecosystems and
biomes.
Natural capital (=goods & services)
Ecological infrastructure
Natural heritage
What is Biodiversity?
Hierarchy of scales:
• Biomes
• Landscapes – vegetation types/
ecosystems
• Habitats – communities of plants,
animals & microbes
• Populations - genes
Biodiversity in Cape Town
• Cape Floristic Region (CFR)
has half of SA’s plant
biodiversity in only 4% of area
• Cape Town has one third of the CFR’s biodiversity (Over
3000 plant species) in under 3% of the CFR area
We are a global biodiversity hotspot without parallel !!
NEM:BA THREATENED ECOSYSTEMS: 2011
440 Vegetation types - 19 in city
21 are Critically Endangered - 11 in city
- 6 endemic vegetation types (3 CR)!
- 13 extinct plant species
- 319 threatened with extinction
2011 NEM:BA
Historical Vegetation
2013 vegetation
Transformation:
2/3 agriculture
1/3 urbanization
Proclaimed reserves
City Land Use
150000
140000
urbanization
130000
agriculture
120000
unproclaimed vegetation
proclaimed reserves
110000
100000
Area (ha)
90000
80000
70000
60000
50000
40000
30000
20000
10000
0
1900
1920
1940
1960
Year
1980
2000
7% remains
3%
conserved
TARGET:
30%
Lourensford Alluvium Fynbos - CR
Peninsula Shale Renosterveld - CR
11% remains
10% conserved
TARGET: 26%
14% remains
1% conserved
TARGET: 30%
Cape Flats Sand Fynbos - CR
Restoration essential to save species
OPPORTUNITY TO RESTORE EXTINCT SPECIES
Erica verticillata EW
Erica turgida EW
FIRE IS ESSENTIAL
FOR RESTORATION
Major threat in Urban areas to Conservation
Fire legislation
FYNBOS
MUST
BURN!
Mowing eradicates
Fynbos
Cape Flats Dune Strandveld – EN
45% remains
13% conserved
TARGET: 24%
Peninsula Granite Fynbos
CR
N
S
68% 34% remains
58% 30% conserved**
TARGET: 30%
Peninsula Sandstone Fynbos – EN
97% remains
94% conserved
Importance of Cape Town’s biodiversity?
Legal responsibility to conserve biodiversity for
future generations
CBD; NEMA; NEM:BA; NEM:PAA; Countdown 2010; City
strategies etc
Importance of Cape Town’s biodiversity
Economic value: goods & services;
ecological infrastructure
E.g. clean water; coastal & soil stabilization
Replacement value = R2 - R6 billion / year!
Underpins tourism industry
Direct job creation (e.g. Zeekoevlei = 8200 pdpa)
Intrinsic value through its mere existence
Consumptive use value (e.g. harvesting)
Importance of Cape Town’s biodiversity
Educational value – potential outdoor EE opportunity within
walking distance of every school. (over 24,000 learners
partook in City EE programmes in 2012)
Social value through recreation and open space (integral to
health and well being)
Aesthetic value through beauty and scenic drives
Spiritual value
Bequest value – the value of retaining biodiversity for future
generations
Option value – value of retaining biodiversity for future use
Climate change – mitigation and adaptation
Threats to biodiversity in Cape Town
Habitat loss & fragmentation
Urban development
Agriculture
Invasive species
Inappropriate fires
Mowing
Over-exploitation
Pollution (N-deposition)
Hydrological change
Crime
All need to
be addressed
for Smart
Living!
Khayelitsha
Acacia saligna
invading Sand Fynbos
Conservation Planning
Biodiversity
Network
Sound Spatial Planning: ensuring that the BioNet is a key
informant in the SDF as well as district SDPs and EMFs
NATURE RESERVE CONSERVATION PROTECTION:

Many of the conservation areas have no real
conservation protection
 Reserves will be proclaimed under the
Protected Areas Act (NEM:PAA)
 Secondary sites of conservation importance
will be protected as Biodiversity Agreements
under the Western Cape Nature Conservation
Ordinance
Benefits of conservation protection:
- Shows the intent of the Municipality
- Excellent publicity opportunities
- Expertise from CapeNature
- Friends groups rally around proclaimed sites
- Funders are more keen to invest in “safe” sites
- The holistic management of fire and aliens is
far more cost effective.
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