Module 7

• Biodiversity


  The variation and richness of life at a particular scale
• Humans are part of a complex system and interdependent web of life and we are trying to understand our place in it
• Species extinction has fast accelerated to up to 1,000 times more than normal


  Last fifty years
• Species become extinct even before they are discovered and named
• First Earth Summit in Rio de Janeiro concluded that human activities were fast destroying ecosystems through loss of biodiversity at alarming rates


  1992
• Since the 1992 Earth Summit, there was an increase in desire to understand biodiversity loss and its impact on ecosystems
• Levels of biodiversity


  • Genetic diversity
  • Species diversity
  • Ecosystem diversity
• Genetic diversity


  The sum total of information contained in the genes of species of plants, animals, and microorganisms
• Species diversity


  The variety of species, including their abundance, distribution and functions or interactions within a given spatial context
• Ecosystem diversity


  The distribution and abundance of habitats, biotic communities, and ecological processes in the biosphere
• Compositional biodiversity


  • Describes the type of elements and the number of representatives present at each level (genes, species and habitat) in an area
• Structural biodiversity


  • Describes the variety of arrangement of these components, i.e. the variety of ways in which different habitats, species or genes are arranged over space or time
• Functional biodiversity


  • The variety of biological processes, functions or characteristics of a particular ecosystem/area
• Anthropocentric benefits


  The many potentials for different lifeforms to provide information necessary for science, materials that are useful to humans, and all other recreational, medical, or consumptive benefits
• Ecocentric benefits


  The intrinsic value of biodiversity which is beyond any potential human uses
• Surrogate species


  Species that can represent a broader set of species and/or habitats to support conservation or management strategies
• Keystone species


  Species that play essential community roles and their impact on the community or ecosystem are much larger relative to its abundance, and more influential than expected
• Measuring and monitoring biodiversity

  • Ideal: measure actual processes such as rates of productivity, pollination rates and patterns, species interaction, etc.
  • Simpler and quicker approach: use of surrogate species that can represent a broader set of species and/or habitats to support conservation or management strategies
• Keystone species


  Play essential community roles and their impact on the community or ecosystem are much larger relative to its abundance, and more influential than expected
• Keystone species


  • Tropical figs
  • Mangrove trees
• Umbrella species


  Require such large areas of habitat that their protection might automatically protect a large number of naturally co-occurring species in several ecosystems and habitats
• Umbrella species


  • Philippine Eagle
  • Marine turtles
• Indicator species


  Species that set a benchmark against which comparisons can be made after a period of time whether conservation interventions are applied or not, sensitive to certain changes in the environmental factors
• Indicator species


  • Sub clover Trifolium subterraneum
  • Giant Golden Crowned Flying Fox
• Flagship species


  Popular, charismatic species that serve as symbols and rallying points to stimulate conservation awareness and action
• Flagship species


  • Mindoro 'Tariktik'
  • Philippine Eagle
• Causes of biodiversity loss

  • Population growth
  • Habitat loss (deforestation, loss of mangrove species)
  • Invasive alien species
• Human population density


  Key threat to bird and mammal species
• Deforestation causes species reduction or loss and contributes to climate change
• Mangrove degradation in the Philippines is attributed to its use as firewood and conversion into aquaculture
• Invasive alien species can disrupt ecosystems and outcompete native species
• Invasive alien species (IAS)


  When a living species (animal, plant or microorganism) not commonly found in a specific location becomes dominant, it is referred to as invasive
• Invasive alien species (IAS)


  Species whose introduction and/or spread outside their natural past or present distribution threatens biological diversity
• Important mechanisms for the transport of invasive species are human-related activities including ballast water of ships
• Invasion is finalized when IAS are able to reproduce rapidly in their new environments
• The root cause of biological invasion is actually trade, travel, and modern technology
• Biological invasion has been considered as an important driver of biodiversity loss
• Economic losses in agricultural and fisheries production have been attributed to biological invasion as well, including expenses related to control and eradication of these invasive species
• The IUCN through the Invasive Species Specialist Group (ISSG) runs a website that is a good source of information on invasive alien species including a search engine called the Global Invasive Species Database (GISD) where you can look for specific invasive species of your interest
• The ISSG, likewise, published the World's 100 Worst Invasive Alien Species with available profiles of each species