biodiversity

biodiversity

the richness of biological variation, possible partly because of the many different combinations of environmental conditions on earth

species diversity

species richness measures the number of different kinds of organisms within a community; inversely related to geographic isolation (more isolated population = less rich) and environmental stress (stability of the environment, i.e. seasons and harsh conditions)

ecological diversity

measures the richness and complexity of a community, includes many niches, tropic levels, and ecological processes that capture energy, sustain food webs, and recycle material

edge effect

species richness is greater at the edges of adjacent communities, i.e. ecotone - transitional zone has a lot of richness

species evennes (dominance)

the extent to which the number of individuals of different species are equal or skewed

value and importance of biodiversity

intrinsic value, food security, drugs and medicines, ecosystem services, maintenance of ecosystem function, aesthetic/recreational/cultural benefits, environmental monitoring, biomimicry

ecosystem services

processes by which the environment produces resources or provides services that we often take for granted, but upon which we are dependent (.e. food, fuel, fibre, shelter and building materials, air purification, etc)

maintenance of ecosystem function

high levels of biodiversity increase the stability and resilience of an ecosystem

ecotourism

can be an important form of sustainable economic development

biomimicry

imitating nature’s design and processes to solve human problems, i.e. velcro, bullet trains, wind turbines, gecko tape

environmental monitoring

i.e. canaries in the coal mine gave an early warning for the miners to get out as it was an unhealthy environment

threats to biodiversity

natural causes of extinction, habitat destruction (urban sprawl, deforestation, fragmentation), hunting and fishing, commercial products and live specimens, exotic species introduction, diseases, pollution, climate change

natural causes of extinction

happens in periods of millions of years, in an undisturbed ecosystem, the background rate for mammals and marine animals is an annual rate of 1 extinction per 1-10 million species, i.e. approx. one species lost per decade; human impacts have accelerated that rate

the great acceleration

since 1800, the global population has grown sevenfold and the global economy has grown 30-fold

anthropocene

a new geologic epoch; the impacts of humans can be detected in the lithosphere, a specific time when humans started influencing the rock strata

IUCN red list

list of species facing a high risk of extinction; amphibians are at the highest risk along with a high loss of corals, whose survival rate has diminished

living planet index

a metric developed by the WWF and the UNEP recognizes that biodiversity loss is more than just extinctions but also a decline in population and geographic range; summarizes trends in populations of over 2500 vertebrate species

human-caused reductions in biodiversity

increasing wealth; growing populations and poverty, have to find ways to meet the basic needs of the community, i.e. overfishing or cutting down trees

habitat destruction/loss

urban sprawl, destruction, fragmentation, degradation; the largest threat to species

theory of island biography

distant islands support fewer species than islands closer near the shore (the distance effect), larger islands support more species than small ones and have lower extinction rates as more individuals lead to more genetic diversity and increased resilience to change or destruction

migration

species migrate, i.e. birds need to stop and rest along their path, and if the habitats along the flyaway are destroyed, they cannot migrate properly

pollution

acid precipitation, ozone, depletion, climate change, direct/indirect poisoning, altered habitat from chemicals

overexploitation

hunting and fishing, the over-harvesting of game species; endangered species consumption, a lot of cultures enjoy eating or keeping endangered species as pets; commercial harvest, i.e. zoos, laboratories, pet industry

predator and pest control

many animal populations have been greatly reduced or exterminated because they are regarded as dangerous to humans or livestock, i.e. birds, coyotes, wolves, prairie dogs

exotic species introduction

exotic organisms are introduced into habitats where they aren’t native and become invasive when they cause economic or environmental harm, i.e. ships pouring out ballast water can cause the introduction of new species

conservation biology

study of human impacts on organisms, development of ways to protect biodiversity; two techniques: in situ and ex-situ

ex-situ conservation

zoos, aquaria, botanical gardens, collecting eggs, seeds, captive breeding to reintroduce species (i.e. California condor, seed banks)

ex-situ pros

saving the species, an opportunity for scientific studies, studying species to better understand them, successful breeding

in-situ conservation

protecting the area or habitat where the species lives instead of bringing it into a controlled setting, i.e. northern spotted owl

in-situ considerations

size (how much land is enough), shape (wide vs narrow land space), cost (how much will it cost, economic benefits/disadvantages), location (value of land, environment), targeting what species and areas will be saved with limited funds; i.e. grizzly bears, boreal/woodland caribou

biodiversity hotspots

identifies regions where the threat is greatest to the greatest number of species and allows conservationists to focus cost-effective efforts there; to qualify, a region must supper 1500 endemic plant species and must have lost more than 70%

ex-situ cons

expensive, inbreedings, potential loss of natural instincts