3.0 biodiversity and conservation

biodiversity

quantifiable version of nature which helps policy-makers in suggesting what to do

species diversity

the number of species and abundance of each species that live in a particular location

genetic diversity

range of genetic material present in a gene pool and the amount of variation that exists between different individuals within different populations of a species

habitat diversity

range of different habitats per unit area in a particular econosytem of biome

advantegous of habitat with high biodiversity

• resiliance and stability

• genetic diversity

• some plants will have deep roots so they can cycle nutrients

disadvatgates of habitat with high biodiversity

• could be as a result of fragmentation of habitat

• managing grazing can be difficult

• tolrence is different between plant species

hotspots

regions with high levels of biodiversity that is under threat from human activits

tropical rainforests

vulnerable due to:

• deforestation

• imablanced flow of nutriends

• hotspots

speciation

gradual change of species over a long time

physical barriers led to

• large flightless birds

• marsupials

• placental mammals

land bridges have led to

• allow species to invade new areas

• may result from lowering sea levels instead of continental drift

influecne of plate activity on biodiversity

• covergence: created Himalayas, Andes, etc.

• diverge: mid-atlantic ridge, physical seperation of populations

continetal drift

reulted in new habitants

6th mass exctinction

• Believe that we are in it right now

• Caused by anthropogenic influences

• Wiping out of animal species

• Pollution, overpopulation, etc

5th mass extinction

• 251 million years ago

• Known as the ‘great dying’

• 95-96% of all species went extinct

factors maintaining biodiversity

• complexity of the ecosystem

• stage of succesion (communities in young ecosystems that are undergoing succession may be more vulnerable than older, more stable and resilient ones)

• limiting factors  (water in a desert, competition with other organisms, temperature, etc)

• Inertia: property of an ecosystem to resist change when subjected to destructive force

factors leading to a loss of biodiversity

• Natural hazards (volcanoes, earthquakes, hurricanes, etc)

• Loss of habitat (due to anthropogenic activities → deforestation, in mediterranean, only 10% of the original dorset cover remains)

• Fragmentation of habitats: large area is divided into smaller areas due to establishment of factories, houses, cites, etc

• Pollution (pesticides, oil spills, emissions - lead to acid deposition or photochemical smog, run-off from fertilizers, climate change - alters weather patterns and shifts biomes away from equator)

• Overexploitation (overfishing - use of technology to find hotspots of fish)

• Introducing exotic/non-native species

what makes a species vulnerable to extinction

• Narrow geographical range

• Small population

• Declining population

• Low population density and large territory

• Few populations of species

• A large body

• Low reproductive rate

• Seasonal migrates

ICUN

International Union for Conservation of Nature and Natural Resources (IUCN)

Red list: determines conservation statues of a species based on criteria - most are stated above under “what makes a species prone to extinction

Why conserve biodiversity

• economic

• ecological

• social

• aesthetic

value of biodiversity

• Food sources (case studies: wheat rust disease, introduction of resistant genes from a wild strain of wheat in turkey)

• Scientific and education value

• Biological control agents

• Gene pool

• Recreational

• Ecotourism

• ethical/intrinsic value

• Environmental services

1st law of thermodynamics - conservation of energy

• Energy is an isolated system can be transformed but not be created or destroyed

• Equilibrium is very important

• Balance is required in the system

• Order to disorder

2nd law of thermodynamics - entropy

entropy (unavailability of a system's thermal energy for conservation into mechanical work)

• Amount of disorder in the system

• More entropy = less order

• Energy of the universe dispersed (order > disorder) energy spreader as universe spreads infinitely

• Energy conversions are never 100% efficient

• Energy is always lost in the environment as heat

• Organisms reverse entropy

steady state equilibrium

• Human body sweats to cool down and shivers to heat up to keep a steady body temperature

• Non-living things are static

approaches to coservation

• Human health

• Human rights

• Recreational

• Ecotourism

• ethical/intrinsic value

keystone species

a keystone species is a species that has a disproportionately large effect on its natural environment relative to its abundance