Ecosystems

Ecosystems

1. Organism require certain elements to build their bodies and metabolic process

   • Phosphorus
     • -Plants: take up phosphates dissolved in soil water. -Aquatic producers: in water -Animals: by eating producers or any other animal
     • -Component of ATP -Phospholipids -Nucleic acids

2. Ecosystem: Array of organisms and abiotic things, interacting through a one flow energy and cycling of nutrients

   • Primary producers (autotrophos) Energy from nonliving things
     • Consumers (heterotrophos) By feeding on tissues wastes and remains of producers.
       • Consumers: -Herbivores: plants -Carnivores: meet. - Parasites: living host -Omnivores:plants and animals -Destritivores: small particles of organic material -Descomposers: organic wastes(bacteria and fungi)

3. THE NATURE OF ECOSYSTEMS

   • Trophic Estrucutre of Ecosystems
     • Trophic levels: hierarchy of feeding relationship position in Food Chain
       • Food Chain:sequence of steps of energy
         • 1st level: Primary producers: obtain energy from a nonlivingsource.-sunlight-
           • 2nd level: Primary consumers: Get energyand carbonby feeding on tissues and wastes
             • 3rd level: Second consumers: feeding on insects and tissues
               • 4th level: Third consumers: feeding on other animals

4. THE NATURE OF FOOD WEBS

   • Food Web: food chains of an ecosystem cross-connect
     • Two division:
       • Graning food web
         • Primary Producers eating by Primary Consumers
       • Detretial food web
         • Energy producers hows to detritivores
     • Number of tranfers are limited.
       • Energy captured by producers passes through no more than 4 or 5 trophic levels
         • -Shortest: conditions vary widely -Longer: weathers has no effect -Complex: large variety of herbivores. -Fewer: more carnivores

5. ENERGY FLOW

   • System's gross primary production: energy captured by producers
   • Net primary production: portion used for growth and reproduction
   • Ecological pyramids: trophic structure
     • Biomass pyramids: dry weight of all organisms
     • Energy pyramid: how amount of energy diminishes as it is transferred through an ecosystem
   • Ecological Efficiency
     • Factors that influence the efficiency of tranfers
       • E.E is higher in aquatic ecosystems
       • Some components of a body may be unavailable to a consumer
       • Some is lost as metabolic heat

6. BIOGEOCHEMICAL CYCLES

   • An element essential to life moves between a community and its enviroment through the living component.
   • THE WATER CYCLE
     • Moves water from the ocean to the atmosphere, onto land, and back to the ocean
       • -Liquid -Evaporation -Condenses -Precipitation
     • Watershed: area in whict all precipitation drains into a specific waterway.
       • Soil water: some water remains between soil particles
       • Aquifers: water that drains through soil layers often collect
       • Groundwater: soil water and soil aquifers
       • Runoff: water that flows over soil into streams
     • Movement of water
       • Movement of: -carbon -nitrogen -phosphorus
     • Limited fresh water
       • Majority of Earth's water is too salty to drink or irrigales crops
   • THE CARBON CYCLE
     • Atmospheric cycle: biogeochemical cycle in which a gaseous form of an element plays a significant role
     • Terrestial Carbon cycle
       • Land plants take up CO2 to carry out photosynthesis
       • Soil Carbin consist of humus and organisms
         • Bacteria and fungi decompose humus and release carbon dioxide
     • Marine Carbon Cycle
       • Bicarbonate HCO3
       • Organisms release CO2 by aerobic respiration
     • Carbon Fossil Fuels
   • PHOSPHORUS CYCLE
     • Movement of phosphorus among Earth's rocks and waters
     • Limiting factor on plant growth
     • It's a component of all nucleic acids and phospholipids
   • NITROGEN CYCLE
     • Most organisms cannot use this gaseous form
     • DNA RNA Proteins
     • Nitrogen fixation: incorporation of nitrogen from nitrogen gas into ammonia
       • Bacteria break the bonds in N2. Form ammonia, then dissolves to form ammonium NH4
         • Plants take ammonium from soil water
           • Consumer obtain nitrogen by eating them
             • Bacteria and fungal descomposer return ammonium to the soil by a ammonification
               • Ammonification: breakdown of nitrogen-containing organic material resulting in the release of ammonia and ammonium ions
     • Nitrification: converts ammonium to nitrates
     • Denitrification: ecosystems lose nitrogen
     • Disruption of the Nitrogen Cycle
       • Burning fossil fuels and use of industrially produced trinitrogen fertilizers have altered the nitrogen cycle
       • Nitrous Oxide
         • N2O can remain in the atmosphere for more than 100 years
       • Nitrate Pollution NO3
         • Water pollutant
         • Ingest nitrate has negative effects. -Cancer -Respiratory infections. -Diabetes

7. GREEN HOUSE GASES AND CLIMATE CHANGE

   • Green house effect: ability to absorb and reradiate heat energy. Helps to keep Earth warm enough
   • Changing Carbon Dioxide Concentrations
     • CO2 annual level in increasing
     • Analysis of ices cores has provided a history that extends back 800,00 years
       • Also fossil foraminiferan shells helped in the research
   • Global climate change
     • A long-term of Earth's climate. Example global warming
     • Intergovermental Panel on Climate concluded that is very likelly that a human-induced increase in atmospheric greenhouse gases is responsible for the current warming trend