LEC342 - Lecture 1

LEC342 - Lecture 1

1. Biodiversity

   • = comprises all the millions of different species that live on our planet, as well as the genetic differences within species. It also refers to the multitude of different ecosystems in which species form unique communities, interacting with one another and the air, water and soil

2. Conservation

   • The preservation, protection or restoration of the natural environment and wildlife

3. The 'Great Acceleration' - everything's increasing

   • Population, GDP, energy use, water use, telecommunications etc.
   • Causes unintended consequences
     • Carbon dioxide, nitrous oxide, methane, fish capture, tropical forest loss, ocean acidification etc.

4. Principle causes

   • Indirect drivers
     • Human population growth - doubled 1960-2000
     • Increase in economic activity - increased ~7 fold 1950-2015
       • Moderated by...
         • Socio-political factors - increase in democracy & local power
         • Cultural factors - education & environmental stewardship
         • Technological change - increased efficiency of utilisation
   • Direct drivers
     • Land cover change for agricultural conversion
       • Affects 86% of all threatened birds, 86% of threatened mammals & 88% of threatened amphibians
       • ~75% of all known land species live in tropical moist forest - this ecosystem has halved in last 100 years
       • >30% terrestrial ecosystems are considered 'degraded'
     • Over exploitation (harvesting, industrial agriculture)
       • Affects 30% of threatened birds, 33% of threatened mammals, 6% of threatened amphibians, reptiles and marine fishes
         • Atlantic cod stocks off East Coast of Newfoundland - example from another module
         • Fisheries - a 'trophic slide' effect
       • Trade in wild plants and animals & their derivatives is estimated to be >$200bn annually
     • Invasive species (affecting island biota and freshwater systems)
       • = non-native species to an ecosystem whose introduction does or can harm human wellbeing, environmental & economic health
       • Affects 30% of threatened birds & 11% amphibians
         • Most common cause of bird species extinction since 1800 - especially those on islands
           • Mostly due to predators
     • Pollution (particularly nutrients)
       • Eutrophication from increased nutrient concentrations
       • Other pollutants e.g. pesticides, ammonia, PCBs, poly aromatic hydrocarbons are also of concern
       • Discharges from agriculture have caused huge biodiversity loss in marine environments
       • Nitrogen fertilisation/pollution
         • As of 2000, 50% of inorganic N ever used were applied in the preceding 15 years
         • Helped considerably in meeting increasing demand for food
           • But there are significant environmental (& human health) problems
             • 'Dead zones' = N stimulates phytoplankton & zooplankton, decomposition of dying plankton by bacteria starves the water of oxygen - death of fish & invertebrates
     • Climate change
     • Most habitat loss occurred by 1950

5. Lots of general things about decreasing biodiversity and how we need ecosystem services etc.

   • Better off finding a few in depth examples for exam questions

6. Why should we be concerned?

   • Loss of flagship etc. species
   • Pressure on ecosystem services
   • The Convention on Biological Diversity
     • Strategic Goal A
       • Address the underlying causes of biodiversity loss by mainstreaming biodiversity across government and society
     • Strategic Goal B
       • Reduce the direct pressures on biodiversity and promote sustainable use
     • Strategic Goal C
       • To improve the status of biodiversity by safeguarding ecosystems, species and genetic diversity
     • Strategic Goal D
       • Enhance the benefits to all from biodiversity and ecosystem services
     • Strategic Goal E
       • Enhance implementation through participatory planning, knowledge management and capacity building