Topic 4 Conservation and Biodiversity
Topic 4.1 Biodiversity in Ecosystems
Notes Ch. 5 Biodiversity
1. Total World Biodiversity
A)
B)
C)
D)
How many “known” species? – 1.4 – 1.8 million
How many estimated species? 100 million or 8- 10 million
List 4 kingdoms of organisms – Animalia, Plantae, Fungi, Bacteria
Which major group of which kingdom has highest % identified ?
vertebrates = 93 % ;
E) Which major group of which kingdom has lowest % identified? algae(
plantae) = 3 %
F) Plants = 85 % vs. Insects at 11% ?
2. Background and Mass Extinctions
A) Define background rate and approximate number - natural extinction rate
.It’s about 10 – 100 species per year.
B) What are some factors surrounding the background rate that are difficult to
explain?
-
Some species will be extinct before we even know they existed
some believe the current rate is about 1000 times the background rate
extinction rates depend on location, hotspots for example
Mass extinctions may be causing the rate to be much greater than the
background rate
Homo sapiens
3. Geological Time Scale
Know the following:
A)
B)
C)
D)
E)
age of earth and the universe – 4. 6 billion, 13.7 billion
extinction date of dinosaurs – 65 million years ago
when humans appeared – 200 000 years ago
Sequence of major eras : Precambrian, Paleozoic, Mesozoic and Cenozoic
Over how many years did the last 5 mass extinctions occur ? 500 million
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4. The Sixth Mass Extinction
A) What is the cause? humans
B) What is a “weedy” species? – successful species in today’s current mass
extinction
C) Are we a “weedy” species? – no one is really sure
D) List 4 things humans do to be the direct cause of ecosystem stress :
- transform the environment- with cities, roads and industry
- overexploit other species – in fishing, hunting, harvesting
- introduce alien species – which may not have natural predators
- pollute the environment – which may kill species directly
E) Hotspots : Define the criteria that determines if an area is a Hotspot or not.
threatened areas where 70% or more of the habitat has been lost and which
contains more than 1500 species of plants which are endemic.
F) Define endemic species – species only found in that area- unique
5. Keystone Species – Types of Diversity
A) Define Keystone species and give 2 examples.
Important species that many other species and the ecosystem depend on. If lost of
this one species may lose many other species.
Ex. A small predator may keep herbivore in check. If not herbivore could go rampant
and wipe out many other plant species
EX. Beavers ( engineer species) make dams that create swamps that create huge
number of swamp species
B) Explain biodiversity . Define two types of biodiversity with one example of
each.
1. Species diversity – both range and number ex. forest has 15 diff. species with
100 individuals of one species and one individual of the other 14 species.
Low on habitat spread diversity.
Another forest has 15 species and 7 individuals of each species. Better on
habitat spread diversity. Higher species diversity
2. Genetic diversity – the range of genetic material present in a species or a
population, the gene pool. It reflects the genetic variety that exists within a
species, which determines the amount of variation between different
individuals.
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A small population usually has less genetic diversity.
3. Habitat diversity – number of different habitats per unit area. Tropical
rainforests high, Tundra low.
6. How New Species Form / Plate Influence on Biodiversity
A) Explain speciation related to NATURAL SELECTION . Use the following in
your explanation :
-
geographical or reproductive barriers
genetic variation and competition among individuals and how this may lead
to speciation
limited resources
natural selection as a major force for speciation and EVOLUTION.
how fast is speciation?
briefly explain 2 specific examples of speciation
Isolation leads to new species in general
B) Plate Influence and Continental Drift on Biodiversity
Explain effect of plate tectonics and continental drift on
Llamas and camels – both have similar ecological roles as pack animals and for
meat. Had a common ancestor but due to plate tectonics were separated –
geographical isolation – and developed into new species.
Kangaroos and cattle – both have similar ecological roles as herbivores to eat grass
and convert to meat. Australia separated via plate tectonics and developed unique
species . Cattle , placental animals, outcompeted the marsupials in other parts of the
world. Thus you can only find kangaroos in Australia.
Basically had similar ecological roles and common ancestors
7. Factors that affect Biodiversity
A) List the factors that maintain biodiversity : complexity of ecosystem, stage of
succession ( few species at first , then more diversity , then community
climax) , limiting factors ( biotic factors – predators, humans; abiotic factors –
water, climate) , inertia ( ecosystems that resist change when subjected to a
disruptive force)
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B) List the factors that lead to a loss of biodiversity : natural hazards ( volcanic
eruptions, NATURAL fires, tsunami) not by humans;
Humans : loss of habitat ( biggest cause) by fragmentation, pollution,
overexploitation, introducing nonnative ( exotic) species, spread of disease,
modern agricultural practices
C)
-
Vulnerability of tropical rainforests:
what may happen in 50 years ( be completely gone
contain __50_ % of earths’ timber ( timber # 2 natural resource after oil)
once cleared rain forest can only grow crops for about two years , why? - fast
rate of respiration and decomposition means that the forests APPEAR to be
very fertile, HOWEVER, most of the nutrients are in the huge trees and plants
and NOT in the soil. Once cleared, soil is not really fertile and will only last
about 2 years. Fertile soil is like the Midwest US ,valleys in china , Nile river
valley, which will support farming for 100s of years.
8. Extinction
List the factors that make some species vulnerable to extinction ( make sure you
understand them). Think of some examples.
a) Narrow geographical range - ( species can only live in 1 type of area) ex.
p.115 Golden Lion Tamarin only found in atlantic rainforest, pandas in N.
china bamboo)
b) Small population – ( less genetic variation and can not adapt to change very
well)
c) Low population densities and large territories – ( individual species requires
large territory to hunt and only meets mate for reproduction once in a while
– mountain lions, pumas, humpback whales)
d) Few populations of the species
e) Large Top predators ( p. 48 biomass pyramid , only 10% is passed to next
level so top predators have large ranges , low densities and need a lot of food
f) Low reproductive potential - reproduce slowly ( whales , penguins only 1
egg per year)
g) Seasonal Migrants – species that migrate have more problems: long routes,
mating habitat destroyed , weather,
h) Poor dispersers - species that are not mobile, example plants, flightless
birds, cannot escape if habitat goes bad.
i) Specialized feeders or niche requirements - due to lack of natural selection
pandas can only eat bamboo shoots, koala bears can only eat eucalyptus
leaves, the sundew plant can only live in very humid places
j) hunted for food or sport
k) Human activity causes extinction to occur faster vs. slower extinction rates
due to natural causes
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9. Case Studies
Find an example of one that is not in the textbook. Write description, ecological role,
pressure, method of restoring population
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Topic 4- Conservation and Biodiversity
Notes ch. 6 – Conservation of Biodiversity
1.
a)
b)
c)
d)
e)
f)
g)
h)
Definitions
Red lists
Bio right
Conservation
Preservation
CITIES
UNEP, WWF, GREENPEACE,IUCN
NGO – GO
Corridor
2. Why Conserve Biodiversity? Arguments – Economic Reasons
a) Explain direct value and give one example of a food source and one
example of a natural product.
b) Explain indirect value and give 1 example :
c) Make sure you know and understand the following types of indirect values:
i)
Ecosystem productivity – what is the main topic sentence?
“ecosystem productivity gives us environmental stability and
recycles materials. “
They are very complicated and rely on many species, biotic and abiotic
factors. Pollination depends on insects, plants capture carbon and
release oxygen. Climate is regulated by rainforests and vegetation
cover.
ii)
Scientific and educational value : make sure you know and
understand examples listed in textbook. Add aesthetic values ( not
in textbook).
Biological control agents- ladybirds eat pests called aphids
Genes- hybrids, gmos, genetic engineering
Environmental monitors – miners used canaries to test for toxic gases
Recreational – parks, ecotourism
Human health – medicines, medicinal plants, cure for cancer – amazon
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Human rights – preserve rainforests to preserve Indians
Ethical/ aesthetic/ intrinsic value – humans are responsible for nature
Biorights – preserve ecosystems as a whole and reduce $$ and need to
concentrate on single species later on
3. Conserving and Preserving Biodiversity
Conservation biology vs. preservation biology : explain the difference and give an
example.
4. Methods : explain each
A) Conservation Organizations- GOs, NGOs , WWF, IUCN,
GREENPEACE, UNEP. Do Which is which research p. 122 of text.
Table 6.1 good : how GOs and NGOs compare :
Media – GO prepare and read written statements – typical politicians.
NGOs use media to gain attention – typical journalists
Speed of response - GOs slow as always. NGOS faster
Political constraints – GOs a lot .NGOs none
Enforceability – GOs International agreements and laws. NGOs none, use
public opinion to put pressure on GOs.
WWF and GREENPEACE – NGOS
UNEP ( from Wikipedia) - The United Nations Environment Programme
(UNEP) coordinates United Nations environmental activities, assisting
developing countries in implementing environmentally sound policies and
practices. It was founded as a result of the United Nations Conference on
the . Its activities cover a wide range of issues regarding the atmosphere,
marine and terrestrial ecosystems. It has played a significant role in
developing international environmental conventions, promoting
environmental science and information and illustrating the way those can
work in conjunction with policy, working on the development and
implementation of policy with national governments and regional institution
and working in conjunction with environmental Non-Governmental
Organizations (NGOs). UNEP has also been active in funding and
implementing environment related development projects.
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IUCN ( from Wikipedia) - The International Union for Conservation of
Nature and Natural Resources (IUCN) is an international organization
dedicated to finding "pragmatic solutions to our most pressing
environment and development challenges." [1] The organization publishes
a "Red List" compiling information from a network of conservation
organizations to rate which species are most endangered.[
B) Red Lists – produced by the IUCN is a collection of threatened species
lists under varying levels of threat to their survival.
C) Species based conservation – the CITIES agreement
The Convention of International Trade in Endangered Species. Species
were becoming extinct due to buying and selling on a global scale for
example, selling Blue Parrots from Brazil. Has about 5000 animal species
and 28 000 plant species on list against law to sell. Since 1975 has been
the most effective international wildlife agreement in the world.
D) Captive breeding programs and zoos
Not very successful. Zoos are nice but not effective. Reintroducing
animals into wild is expensive and only a few successful stories ( eg.
Condor in California, Tamarin Lion in Atlantic Rain forest). Sometimes
reintroducing an animal is impossible because original habitat has been
wiped out.
But what are the alternatives? Text doesn’t give any.
E) Botanical gardens and seed banks ( basically gene banks)
Plants are definitely easier to reintroduce to wild than animals. There are
many seed banks and botanical gardens around the world and the future
for preservation and conservation is much brighter than for animals.
However , entire forests and ecosystems still have a huge problem.
F) Gene banks – may keep DNA for recreating later on but technology
still far away.
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G) Designing Protected Areas – Criteria
Read pp. 128 – 129 of text; See fig. 6.6 explain following criteria:
Size – bigger is usually better because it minimizes edge effects. Smaller
sometimes better due to more diversity in habitat
Shape – circular usually better to minimize edge effects ( ectozones) .
Actually based on what is available so most parks are irregular in shape.
Edge effects- where 2 habitats meet and you get a mix of abiotic factors (
weather, precipitation wind etc. ) occurring at the ectozones. More
different kinds of species will meet at the edges but this will create
competition and predation which is not good for conservation of all
species.
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Corridors - narrow strips of land that connect different park reserves.
Worked well in Costa Rica and other countries but does have some
disadvantages:
-
diseases can spread form on reserve to another
easy access by hunters and poachers
Proximity - basically the way areas are grouped together see fig. 6.6
above
5. Case Studies - know
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