3.1.6.1 ecosystems + sustainability

• Biodiversity

  The variety of organism living in a particular area, all the different species + habitats + ecosystems + genetic diversity
• Species richness

  • Measure of the total num on diff species in an area, doesn't take into consideration of species abundance
  • Lots of information available + exists on patterns of species richness
  • Greater num of species = indicate greater genetic diversity
  • Not adequate for single called organisms
  • Some organisms may be closely related
• Living planet index


  Measure of global biodiversity, brings in multiple data sets of vertebrate populations that are being monitored around the world, used as an indicator of how biodiversity is changing globally
• trends in global diversity, temporal

  Historically, global biodiversity has steadily increased from about 500 million years ago, there has been 5 mass extinctions (natural i.e volcanoes + meteors) + scientists believe that we may be in another period of mass extinction due to humans
• trends in global biodiversity, spatial scale global

  Globally biodiversity increases from poles towards the equator = disproportionately spread, 50% is of p + a live in trf, warmer + humid = plant growth better and can support species which are higher up in the food chain
• trends in local biodiversity, spatial local

  • Locally, farms = low biodiversity, cash crops + monocultures = less resilient
  • declines most rapidly in places where humans are destroying habitats
  • Managed to reduce biodiversity loss, conservation areas such as national parks are protection from human activities that might reduce biodiversity i.e agricultural + mining
  • Green spaces in urban areas + hedges between fields to provide habitats
• LPI = DECREASED OF 58% between 1970 - 2012
• Biodiversity declines by 56% in tropics, 36% in temperate zones, Latin America 83%
• Current rates of biodiversity loss are higher than natural
• Blanket bogs, UK


  • Upland peat bogs - fed by rainfall, accumulation of dead organic material, mainly plant remains that are unable to decompose due to wet, acidic + cold conditions
  • Have rich biodiversity
  • More carbon is stored in UK peat then all the forests in Britain + France combined = combat climate change
• Kinder scout, national nature reserve of moorland


  • Contains blanket peat bog
  • Extremely damaged moorland due to wildfires + overgrazing sheep + air pollution
  • National trust restore peat bog - fences to prevent overgrazing, planting cotton grass, heather is cut and harvested to prevent extensive wildfires + layed over blanket bog to prevent erosion of peat bog, acts as skin, improvise microclimate may facilitate succession
  • Lowered water table due to draining + hotter summers = increases decomp = carbon source?
• Ecosystem


  A dynamic system of relationships between biotic + abiotic factors in a particular environment
• Ecosystem services


  Benefits that people obtain, ,millennium ecosystem assessment 15/24 ecosystems were degraded/ being sourced unsustainably for their services
• Ecosystem services


  • Goods - food + water + wood + fuels + medicinal purposes (provisional services)
  • Environmental - influence the climate + risk of flooding + purification of water ( regulating services)
  • Cultural - pleasure, spiritual
  • Supporting services - nutrient cycling + soil formation
• UK ecosystems services - NEA (national ecosystems assement) - ecosystems services = worth. I'll ions to the economy + health benefits of living to a close green space is up to £300 per person
• Impacts of loss of biodiversity

  • Physical - Extinction of species, cascading effect on ecosystems, food chains
  • Increases greenhouse effect as reduction in plants, may cause droughts or floods
  • Bare soil = vulnerable to erosion, effects productivity then land is left infertile
  • More susceptible to disease + less resilient
  • Death of animals
  • Human - reduce food supplies, insecticides + pesticides = disappearing bees + moths + insects + birds = pollinators
  • Access to chem air water may be reduced
  • Potential medicines = removed
• Sustainability


  Meeting the needs of the present without compromising the further generations needs
• Global pop increases = strain on ecosystem services, products are more difficult to share
• Economic development = more development = more land = more pop = more pollution
• Balance increase in pop size + development with conservation = sustainable
• Ecosystem


  A community if abiotic and biotic tings that work together, they are dynamic
• Flow of energy in an ecosystem is unidirectional, open systems + important to maintain at dynamic equilibrium
• Abiotic factors in aquatic ecosystems

  • Water depth, pH, sunlight + turbidity, water cloudiness (coral reef ecosystems), salinity, nutrients + dissolved oxygen
• Abiotic factors in terrestrial ecosystems

  • Wind, temp, precipitation, altitude, soil + sunlight + topography (layout of lands, elevation, gradient + aspect)
• Aspect


  In the northern hemisphere, south facing slopes receive more sunlight
• Altitude


  Height above sea level
• Soils


  Rich ecosystems + dead organic matter, weathered rock + decomposers + detrivores
• Biotic


  Living organisms, plants + animals + microorganisms
• Producers


  Green plants that have chlorophyll > convert solar energy into chemical energy via photosynthesis using co2 = glucose to be used for resp + storage of starch, produce o2 as a by product of photosynthesis that helps maintain the balance of co2 + o2 in atmosphere, make their own food = autotrophs
• Consumers


  • Primary - herbivores consume plants
  • Secondary - feed on herbivores, primary carnivores i.e cats + foxes + snakes
  • Tertiary - large carnivores that feed on secondary consumers = lions + wolves + humans
  • Quaternary - fed on tertiary, not eaten by anyone else i.e tigers + ions
• Decomposers


  Bacteria + fungi that break down dead organic material of producers + consumers, release simple inorganic + organic substances produced as by products of metabolism
• Detrivores


  Organisms that ingest dead organic material directly
• Biomass


  Mass of living organism in a given ecosystem, expressed by g/m2 or joules/m2
• Aquatic ecosystems have a disproportionate amount of biomass in phytoplankton + rooted plants + krill
• Terrestrial ecosystems have biomass that changes every season
• Gross primary production


  The total amount of energy producers get from photosynthesis
• Net primary production


  The energy available for plant growth, which is the gross primary production minus respiration
• Food chain


  A linear pathway that shows how energy is transferred from the producer to the consumer
• Tend to oversimplify the relationships - a lot of consumers dont just fit one trophic level, birds will eat seed from plant + insects that feed on the plant
• Food webs


  Show multiple food chains and demonstrate different ways energy flows through an ecosystem