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Chapters #5-9 - Coggle Diagram

- - - - Center for Biological Diversity has reported that 631 species + subspecies went extinct in North America between 1642-2001. Recent report claims global biodiversity loss costs as much as $4.5 trillion a year.
      - Biological is important because it provides instrumental value - 1. Food and raw materials 2. Sources for medicine 3. Recreational
        
        Intrinsic value - value that living organisms/species have in their own right (don't have to be useful to have value)
        
        Ecotourism - enterprises involved in promoting tourism of unusual or interesting ecological sites
  - - - Biodiversity is declining around the world. North America + Global extinction on the rise. Up to 1 million species are threatened. Endemic species (species found only in a particular geographic area/habitat) are especially at risk.
        
        Tropics are highly diverse - extinction of species high + deforestation issues
        
        Current threats to biodiversity are described with the acronym HIPPO (Habitat destruction, Invasive species, Pollution, Population, and Overexploitation).
        
        Habitat Destruction (aka greatest source of loss) Types - 1. Conversion 2. Fragmentation 3. Simplification 4. Intrusion of other species
        
        Invasive Species - introduced species that spread out and often has harmful ecological effects on other species or ecosystems
        
        How to deal with it? - Enact laws, Prevent establishment, Remedy situation
        
        Pollution categories - 1. Chemical (Ex: Nutrients, Pesticides, Disrupting Compounds, Industrial Waste) 2. Biological (Pathogens and Parasites) 3. Physical (Sediments, Light, Noise, Thermal)
        
        Biodiversity Loss Consequences - 1. Loss of ecosystem services 2. Keystone species 3. Aesthetics and nature-based tourism 4. K vs R-strategists 5. Unknown consequences
        
        Population Growth - Puts pressure on species (Ex: Direct use of organisms, Habitat conversion for use, Pollution, Competition)
        
        Overexploitation - Overharvesting of particular species faster than they can replenish (Accounts for 23% of recent extinctions. Ex: Trade in Exotics (Typically illegal)).
  - - - Conservation biologists use techniques such as captive breeding, telemetry (transmitting data through remote communication) and tracking devices in order to learn more about natural history of species + to protect those vanishing.
      - Endangered species legislation - Lacey act (first national act that gave protection to wildlife), Endangered Species Act (Mandates protection of species and their habitats that are determined to be in danger of extinction) Alternatives/Roadblocks - special interest groups
- - - - Six major findings from Global Forest Resource assessment: (1) Loss in forest cover (2) Deforestation rate 7.3 million HA/yr (3) used for production of wood (4) 13.5% national parks or reserves (5) Large role in combatting climate change (6) pests and forest damage
        
        Consequences of deforestation - Productivity reduced, reduction in nutrients + biomass, biodiversity reduced, soil erosion increased, alters hydrology, CO2 sequestration lost
      - Methods and management (1) Even cutting - clear-cutting (practice of removing an entire strand of trees, leaves ugly site that takes years to recover) (2) Uneven cutting - Selective cutting (practice of cutting some mature trees from a stand but leaving enough to maintain normal ecosystem functions) Shelter-wood cutting (cutting groups of mature trees over longer periods usually 10-20 years so they can provide seeds and give shelter to growing seedlings)
    - - Aquaculture - Farming of aquatic organisms, growing in developing countries...
        
        Open-ocean aquaculture - farming coastal species in ocean several miles from shoreline
        
        Law of the Sea Treat that defined national rights and responsibilities with respect to the worlds Oceans.
        
        Magnuson-Stevens Fishery Conservation and Management Reauthorization Act - extended the limits of jurisdiction over coastal waters and fisheries of the US to 200 miles offshore
  - - - Ecosystem use: (1) Consumptive: harvest food, shelter, tools, fuel, and clothing (Common in developing countries and even in rural US) (2) Productive: Exploitation for economic gain (Enormous source of revenue)
        
        Protecting ecosystems: (1) Conservation: Management and regulation of ecosystem use (2) Preservation: ensures continuity of ecosystem (or species), regardless of potential utility
        
        Maximum Sustainable Yield (MSY) - Highest possible rate of use system can match with own rate of replacement/maintenance (harvest that will be balanced by regenerative capacity of system)
        
        The optimal population for harvesting the MSY is just halfway to the carrying capacity
        
        Precautionary principle - where there are threats of serious/irreversible damage, the absence of scientific certainty shall not be used as a reason for postponing cost-effective measures to prevent environmental degradation
  - - - Third greatest level of protection - National Forests (740 million acres although 2/3 managed for commercial timber), Fourth level - Non-federal lands Typically through land trusts
  - - - We exploit resources and then lose sight of their ecological value (E.g. mangrove shoreline protection, timber, and fish)
- - - - Food Chain - Transfer of energy and material through a series of organisms as each one is fed upon.
        
        Terrestrial Ecosystems - Trophic levels maintained by an ecosystem usually no more than 3 to 4
        
        Aquatic ecosystems are different from terrestrial in two ways. 1. transfer of energy is more efficient in aquatic systems. 2. Aquatic systems do not always have same kind of biomass pyramid as terrestrial systems. This is because the producers are usually short-lived while those one top live far longer.
        
        When energy flows from one trophic level to the next only a small fraction is passed on due to three reasons
        
        Much preceding trophic level is biomass which isn't consumed by herbivores, 2. much of what is consumed is used as energy to fuel heterotrophs cells and tissues, 3. some of what is consumed is undigested which produces wastes.
      - Tropic Levels: Categories
        
        Producers -> First-order consumers -> second-order consumers -> third-order consumers.
        
        Producers - 1. Autotrophs: produce organic compounds to survive, 2. Chemotrophs: producers use inorganic molecules to gain energy for survival.
        
        Plants use variety of molecules to capture light energy during photosynthesis, the most predominant one of these is chlorophyll (the green pigment that gives photosynthetic plants their color).
        
        Heterotrophs - 1. Consumers which eat living organisms to survive 2. Decomposers which break down dead organic material
        
        Consumers are divided into subgroups according to food source: Herbivores (eat plants) aka first-order consumers. Second-order consumers and higher are Carnivores (eat other animals). Omnivores eat both plants and animals.
  - - - Climate of a given region is a description of average temperature and precipitation (weather) which may be expected each day throughout the year.
        
        Equatorial regions - continuously warm with little seasonal change in temp. Above + below equator - temp become increasingly seasonal.
      - Terrestrial biomes - individual ranges of tolerances (temp and weather), determine whether dominant species can live. The distribution of species describes placement of biomes.
  - - - Disturbance - a significant change that kills or displaces many community members
      - Ecological succession - transition from one biotic community to another
        
        Primary - area lacking plants and soil is initially invaded by plants when soil forms. Secondary - area cleared by disturbance and then reinvaded by plants and animals from other ecosystems
        
        Aquatic - soil particles eroded from land or plant detritus build up in pounds or lakes, eventually filling them.
        
        Fire climax ecosystems - Ecosystems depending on the recurrence of fire to maintain existing balance
        
        Resilience - ability of ecosystems to return to normal after disturbance. Tipping point - situation in human impacted ecosystem where small action catalyzes major change in system state
        
        Facilitation - Driving succession forward by improving conditions for subsequent species.
  - - - Incremental value - measurement of the value of ecosystem services, the incremental value of a service may be calculated when changes in that service occur.
      - Ecosystem services: Restoration - return ecosystems back to original state (requires 1. abiotic factors unaltered or can change to original state, 2. Viable populations formerly inhabiting ecosystem must still exist) Management - manage ecosystem in current state
        
        Millennium Ecosystem Assessment - A governing board (Four-year project involving 1400 scientists). Produced reports on state of Earth's ecosystems (major note of strain on Earth to sustain future generations)
        
        We depend on nature and ecosystem services but live off them unsustainably Ecosystem assessment report: 1) humans profoundly change ecosystems 2) outstanding problems including overfishing, loss of services, climate change, nutrient pollution 3) humans cause species extinction 4) Loss of services is a barrier to solving poverty, hunger, disease 5) pressure on ecosystems will increase unless attitudes and actions change 6) conservations succeeds when local people are involved
        
        Future of ecosystem environmental sustainability problems focus on 1. world population will increase tremendously over next half a century 2. N and P cycles raise nutrients in land and water 2-3 times 3. 15% more agriculture land 4, Global deforestation 5. More water diverted 6, Lose of up to 50% of world's biodiversity
- - - - Human carrying capacity? Yeah! Best guess we got is 7.7 billion people, by removing limiting factors on our population we can increase our carrying capacity.
        
        Revolutions promoting population growth: Neolithic revolution, Industrial, Medical, Green, and Environmental
        
        Population growth: births > deaths
        
        Total fertility rate (TFR) - average number of children a woman has over her life time
        
        Replacement-level fertility: rate replacing population of parents (2.1 for high incomes countries, Higher in low-income counties)
        
        Formula for human impact on environment: I = PAT
        
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        Poor countries tend to have higher levels of fertility than rich countries
        
        Population profiles how us # of individuals at each age or in each 5 year age group; showing us age structure of a population.
        
        Crude Birth Rate, Crude Death Rate, Natural increase rate, and population size are all components of demographic transition. Which is a theory referring to the historical shift from high death + birth rates to low ones.
        
        Demographic transition stages in order - Preindustrial condition, Transitional, Industrial, and Post Industrial
        
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        Neolithic - development of agriculture
        
        Industrial - 19th century, development of manufacturing processes using fossil fuels
        
        Medical - 1800's-20th century, advances in medicine
        
        Green - after industry + medical, increases agricultural efficiency (development of chemical pesticides, fertilizers, etc)
        
        Environmental - Coming change in the adaptation of humans to the rising deterioration of the environment