A Biodiversidade Ecologia Aplicada

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A Biodiversidade

Ecologia Aplicada

Henrique Miguel Pereira

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).

Os diferentes níveis da biodiversidade

Ecossistemas

Espécies

Populações

Biodiversidade

Serviços de Ecossistema são os benefícios que as pessoas obtêm dos ecossistemas

Regulação

Benefícios obtidos da regulação dos processos de

ecossistema • regulação do clima • regulação de doenças • regulação de cheias • destoxificação Produção Bens produzidos ou aprovisionados pelos ecossistemas • alimento • água doce • lenha • fibra • bioquímicos • recursos genéticos Culturais

Benefícios não materiais obtidos dos ecossistemas

• espiritual • recreativo • estético • inspiração • educativo • simbólico Suporte

Serviços necessários para a produção de todos os outros serviços

• Formação do solo • Ciclos dos nutrientes • Produtividade primária

Estrutura conceptual do Millennium Ecosystem

Assessment

História da Biodiversidade na Terra

Regional patterns of biodiversity loss

E os rios também estão

fragmentados

Degradation and unsustainable use of ecosystem

services

  Approximately 60% (15 out of 24) of the ecosystem services

evaluated the MA are being degraded or used unsustainably

  Provisioning services have increased at the cost of deteriorating

Service Status Food crops  livestock  capture fisheries  aquaculture  wild foods  Fiber timber +/– cotton, silk +/– wood fuel  Genetic resources  Biochemicals, medicines  Fresh water 

Capture Fisheries

 25% of commercially exploited marine

fish stocks are overharvested (high

certainty)

Trophic level of fish captured is declining in marine and freshwater systems

Marine fish harvest declining since the

Water

  5 to possibly 25% of global freshwater use exceeds long-term

accessible supplies (low to medium certainty)

  15 - 35% of irrigation withdrawals exceed supply rates and are

Status of Regulating and Cultural Services

Status

Regulating Services

Air quality regulation 

Climate regulation – global _ Climate regulation – regional and local 

Water regulation _+/–

Erosion regulation _

Water purification and waste treatment _

Disease regulation _+/–

Pest regulation 

Pollination _

Natural hazard regulation 

Cultural Services

Spiritual and religious values _

Aesthetic values 

Regulating Services

  Air quality regulation

  Ability of the atmosphere to cleanse itself of pollutants has

declined since pre-industrial times but not by more than 10%

  Regional and local climate regulation

  Changes in land cover have affected regional and local

climates both positively and negatively, but there is a

preponderance of negative impacts ; for example, tropical deforestation and desertification have tended to reduce local rainfall

  Water purification and waste treatment

  Globally, water quality is declining, although in most industrial

countries pathogen and organic pollution of surface waters has decreased over the last 20 years

  Pest regulation

  In many agricultural areas, pest control provided by

natural enemies has been replaced by the use of

pesticides – such pesticide use has itself degraded the capacity of agroecosystems to provide pest control

  Pollination

  There is established but incomplete evidence of a global

decline in the abundance of pollinators

To qualify as a hotspot, a region must meet two strict criteria: it must contain at least 1,500 species of vascular plants (> 0.5 percent of the world’s total) as endemics, and it has to have lost at least 70 percent of its original habitat

To qualify as a hotspot, a region must meet two strict criteria: it must contain at least 1,500 species of vascular plants (> 0.5 percent of the world’s total) as endemics, and it has to have lost at least 70 percent of its original habitat

Conceitos

  Endemismos

  Autóctones/Nativas

  Invasoras

  Exóticas

Valorando a biodiversidade

  Valores utilitários (perspectiva antropocêntrica)

  Uso directo

  Uso indirecto

  Existência

  Valores de opção

Quanta biodiversidade devemos preservar?

Tendência actual

Serviços ecossistema (excluindo valores existência)

Serviços ecossistema + valores existência Serviços ecossistema

+ valores existência+

Métodos de valoração

  Técnicas convencionais de mercado

  Abordagem dos custo de substituição

  Custo de oportunidade

  Técnicas de mercado implícito

  Método do custo de viagem

  Métodos de cálculo de preço hedónicos

  Mercado hipotético

  Valoração contingente

Degradation of ecosystem services often causes significant harm to human well-being

  Degradation tends to lead to

the loss of non-marketed benefits from ecosystems

  The economic value of these

benefits is often high and sometimes higher than the marketed benefits

Timber and fuelwood generally accounted for less than a third of total economic value of forests in eight Mediterranean countries.

Degradation of ecosystem services often causes significant harm to human well-being

  The total economic value

associated with managing

ecosystems more sustainably is often higher than the value

associated with conversion

  Conversion may still occur

because private economic

benefits are often greater for the converted system

Métodos decisórios

  Análise custo-benefício

  Importância da taxa de desconto (discount rate)

  Avaliação de risco

  O princípio precaucionário

  Análise multi-critério

  AIA, AAE

Evolução da Floresta em Portugal

3000 TOTAL _{Pine and other conifers}

Evergreen oak woodlands (montado) Oak and chestnut

Eucalypt

Área (mil hectares)

Pinheiros e outras coníferas

Montado

Carvalhos e castanheiro

Eucalipto TOTAL

ÚLTIMOS 50 ANOS: Expansão significativa da floresta, com uma expansão muito significativa da área de eucalipto, substituindo áreas agrícolas ou de pinhal ardido

Distribuição da biodiversidade

Economic valuation of forest services

Service/Commodity Value

(million €)

Timber 257.6

Cork 221.9

Total of timber goods 479.5

Resins 13.1

Honey 5.6

Fruits 41.2

Wild mushrooms 32.5

Aromatic and medicinal plants 1.9

Game 58.7

Fodder 125.2

Acorn 6.7

Woodland production 17.8

Total of non timber goods 302.7

Recreational use 5.9

Carbon sequestration 26.5

Agricultural land protection 75

Water resources protection 29

Environmental protection 20.1

Total of environmental services 156.5

Desafios para protecção da biodiversidade

  Gestão de populações

  Áreas protegidas

  Restauração e gestão de ecossistemas

  Gestão da paisagem agrícola