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O que é a biodiversidade?

População Recursos e Ambiente

A biodiversidade

Biodiversidade é a variabilidade entre os organismos vivos de todas as fontes, inter alia, meio terrestre, meio marinho, e outros ecossistemas aquáticos e os complexos ecológicos de que esses organismos fazem parte; isto inclui a diversidade dentro de cada espécie, entre espécies e entre ecossistemas (Nações Unidas 1992: Artigo 2).

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Serviços dos ecossistemas

Ecossistemas e bem-estar humano

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Os diferentes níveis da biodiversidade

Ecossistemas

Espécies

Populações

Genes

Importância dos diferentes níveis da biodiversidade

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A biodiversidade por grupos taxonómicos

A biodiversidade inclui as espécies domésticas

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Como medir a biodiversidade?

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A evolução da biodiversidade

História da Biodiversidade na Terra

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Evolução

  Selecção estabilizadora   Selecção direccional   Selecção disruptiva

Black skimmer seizes small fish at water surface

Flamingo feeds on minute organisms in mud

Scaup and other diving ducks feed on mollusks, crustaceans, and aquatic vegetation

Brown pelican dives for fish, which it locates from the air

Avocet sweeps bill through mud and surface water in search of small crustaceans, insects, and seeds

Louisiana heron wades into water to seize small fish

Oystercatcher feeds on clams, mussels, and other shellfish into which it pries its narrow beak

Dowitcher probes deeply into mud in search of snails, marine worms, and small crustaceans

Knot (a sandpiper) picks up worms and small crustaceans left by receding tide

Herring gull is a tireless scavenger

Ruddy turnstone searches under shells and pebbles for small invertebrates

Piping plover feeds on insects and tiny crustaceans on sandy beaches

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Factores que afectam a distribuição da biodiversidade

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Factores

  Temperatura   Pluviosidade   Área   Biodiversidade

regional   Riqueza de outros

taxa

  Latitude   Altitude

Popu

latio

n Si

ze

Low High Temperature

Zone of intolerance

Zone of physiological stress

Optimum range Zone of physiological stress

Zone of intolerance

No organisms

Few organisms

Lower limit of tolerance

Abundance of organisms Few

organisms No

organisms

Upper limit of tolerance

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Sugar Maple

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Relação espécie-área

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Cell 3 South

Cold, dry air falls

Moist air rises — rain

Cell 2 South

Cool, dry air falls

Cell 1 South

Moist air rises, cools, and releases moisture as rain

Cell 1 North

Cool, dry air falls

Cell 2 North

Moist air rises — rain

Cell 3 North Cold, dry air falls

Polar cap Arctic tundra

60°

30°

0°

30°

60°

Polar cap

Evergreen coniferous forest

Temperate deciduous forest and grassland

Desert

Tropical deciduous forest

Equator Tropical rain forest

Tropical deciduous forest

Desert Temperate deciduous forest and grassland

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Dry woodlands and shrublands (chaparral)

Temperate grassland

Temperate deciduous forest

Boreal forest (taiga), evergreen coniferous forest (e.g., montane coniferous forest)

Arctic tundra (polar grasslands)

Tropical savanna, thorn forest

Tropical scrub forest

Tropical deciduous forest

Tropical rain forest, tropical evergreen forest

Desert

Ice

Mountains (complex zonation)

Semidesert, arid grassland

Tropic of Capricorn

Equator

Tropic of Cancer

Mountain Ice and snow

Altitude

Tundra (herbs, lichens, mosses) Coniferous Forest

Tropical Forest

Deciduous Forest

Tropical Forest

Deciduous Forest

Coniferous Forest

Tundra (herbs, lichens, mosses)

Polar ice and snow

Latitude

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Wind

Movement of surface water

Diving birds

Nutrients

Upwelling

Fish

Zooplankton Phytoplankton

Producer to primary consumer

Primary to secondary consumer

Secondary to higher-level consumer

All producers and consumers to decomposers

Fungi

Bacteria

Golden eagle

Prairie dog

Blue stem grass Blue stem grass

Coyote Coyote

Grasshopper Grasshopper

Grasshopper sparrow Grasshopper sparrow

Pronghorn antelope Pronghorn antelope

Prairie coneflower Prairie coneflower

Figure 6-24 Page 117

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A distribuição da biodiversidade

Riqueza específica por país corrigida pela área (plantas vasculares e vertebrados terrestres)

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Riqueza de famílias de vertebrados

Riqueza de famílias de plantas

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Diversidade de famílias de peixes de água doce

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Anfíbios e répteis Pteridófitas

Fonte: Miguel Araújo, Univ. Évora

Biodiversidade

Fonte: Miguel Araújo, Univ. Évora

Análise Canónica Insubstitubilidade

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Transgénicos

Crop

Crossbreeding

Desired trait (color)

Apple Pear

Offspring

Crossbreeding

Best results

New offspring

Desired result

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Phase 1 Make Modified Gene

Identify and extract gene with desired trait

Identify and remove portion of DNA with desired trait

Remove plasmid from DNA of E. coli

Insert extracted DNA (step 2) into plasmid (step3)

Insert modified plasmid into E. coli

Grow in tissue culture to make copies

cell gene

DNA

plasmid

E. coli DNA

Genetically modified plasmid

plasmid

Phase 2 Make Transgenic Cell

Transfer plasmid copies to a carrier

agrobacterium

Agrobacterium inserts foreign DNA into plant cell to yield transgenic cell

Transfer plasmid to surface microscopic metal particle

Use gene gun to inject DNA into plant cell

A. tumefaciens (agrobacterium)

Plant cell

Nucleus

Host DNA

Foreign DNA

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Phase 3 Grow Genetically Engineered Plant

Transgenic cell from Phase 2

Cell division of transgenic cells

Culture cells to form plantlets

Transgenic plants with new traits

Transfer to soil