Earth Systems Flashcards
system
has a set of components that are functionally connected, ordered and interrelated sets of materials and interactions that function as a unit, network of relationships among parts, elements, or components that interact with or influence e/o
4 critical components of a system
power source: responsible for producing the energy necessary for the system (introduces inputs, movements, and transformations); inputs: the materials and energy that facilitate the system; pathways: the movement of inputs (energy and matter) thruout a system, job is to get things from place to place; outputs: materials and energy that leave a system as a result of the system’s function, should equate to inputs to ensure balance
throughputs
rates of flow
open env system
have throughflows of energy and matter, allows interactions with other systems and exchanges of matter and energy, leads to gaining/losing matter
closed env system
allows interactions with energy but prohibits the exit of matter from the initial system, doesn’t lead to losing/gaining matter; Earth is generally a closed system since it doesn’t receive or release matter, but its systems are open
feedback loops
internal systems
positive feedback loop
reinforces or accentuates stimulus, accelerates systems, little input leads to big changes (small changes can trigger a series of effects which create the circumstances necessary for the system to increase the rate of change thereby creating a major change)
negative feedback loop
reduces the impact of a stimulus, promotes dynamic equilibrium (things are allowed to change but must stay within a certain range), focuses on returning back to EQ or balance of inputs and outputs when a change occurs to the system or circumstances in which it functions
Earth’s spatial scales
individual: a single system; local: incorporates individual scale systems and their interactions; regional: involves local scale systems and their interactions within a region; continental: incorporates regional scale systems in a continent; global: incorporation of all continental scale systems in the world
laws of thermodynamics
0th (temp): two systems in EQ with a third are in thermal EQ with e/o; 1st (conservation of energy): energy can change forms but is neither created nor destroyed; 2nd: entropy of an isolated system always increases; 3rd: entropy of a system approaches a constant as temp approaches absolute zero
law of conservation of matter
materials on Earth can’t be created or destroyed but they can change form and move from place to place
4 great spheres of geography
atmosphere, hydrosphere, lithosphere, and biosphere
atmosphere
low-density shell that envelops the surface, majority of its mass is gas, acts as a shield against outerspace debris, solar radiation, etc., an interface between Earth’s surface and the hostile env of space, chemistry provides a habitable planet
layers of the atmosphere
troposphere, stratosphere, mesosphere, thermosphere, exosphere
ozone
found in a layer above the surface, acts as a sunscreen to block UV radiation, surface-level ozone (known as SMOG) is seen as pollution but is healthy
insolation
incoming solar radiation, little is absorbed by the atmosphere and most i reflected, warms up the atmosphere which emits energy back to the sun (terrestrial radiation/energy)
hydrologic cycle
water from oceans evapourates due to solar energy, transpiration from plants releases water vapour, vapour rises to atmosphere and condenses into clouds which are moved by winds, clouds get too much water and releases it back to the surface as precipitation, water can find diff pathways that lead it downwards into oceans or infiltrate the ground and form aquifers, later pushed back to oceans thru pressure
why water is essential for life
ability to change phases, exhibits strong cohesion which is good for chemical transportation, high heat capacity, responds slowly to heat inputs, low density in solid forms, required for production of things like oxygen
lithosphere
solid mineral component of the Earth, provides structures for life to exist, primary source of minerals and nutrients necessary for life processes and infrastructure
4 layers of the litosphere
crust (where life exists), mantle (liquid), outer core (generates electromagnetic fields, flows, liquid), inner core (very hot, solid metal)
biosphere
includes all organic matter, all of life is dependent on all other spheres
photosynthesis
primary building block of organic matter and the foundation of biosphere; requires sunlight, chlorophyll, water, and CO2, solar energy is absorbed to break down CO2 and H20 into sugars and O2, glucose is broken down to use as energy for growth and repair while O2 is released into the atmosphere; important since living things depend on plants for food and oxygen
chemosynthesis
similar to photosynthesis, doesn’t require sunlight, occurs near the bottom of oceans; H2S is produced in ocean vents and CO2 dissolved in water provide the building blocks for glucose and sulfur compounds
respiration
carried out by autotrophs that perform photo- or chemosynthesis and heterotrophs
heterotrophs
feed on other organisms
herbivores
primary consumers, consume plants
carnivores
secondary consumers, usually feed on herbivores (other animals)
omnivores
consume both plants and animals
detrivores (scavengers)
feeds off of living and dead material
decomposers (saprotrophs)
break down dead organisms and wastes into small components which are consumed and/or released back to env
food chains and webs
display a complex set of interconnections wherein energy and matter are transferred thru trophic levels; begins with the sun, autotrophs (1st level), herbivores, carnivores/omnivores, top carnivores (4th level), and ends with decomposition
ecological pyramid
energy, biomass, and numbers decrease at higher trophic levels due to heat loss from respiration (imposes limitations on organisms in terms of carrying capacity)
gross primary productivity (GPP)
total amount of energy produced within plants
net primary productivity (NPP)
considers waste production and available energy, limiting factors include heat, light, water, and nutrients, provides a way to assess/compare ecosystem productivity
water’s key role in dissolving and transportation
active and storage pools (oceans, atmosphere, rivers, reservoirs, etc.) and life/natural processes (evaporation, condensation, precipitation, etc.)
carbon cycle
storage pool of CO2 in atmosphere is taken in by plants and oceans and used by weather; weathering of rocks creates soil carbon, condenses into fossil carbon used for microbial respiration and decomp, photosynthesis and respiration require and release CO2 back to atmosphere, human emissions, and air sea gases are exchanged to use CO2 for marine photosynthesis and released thru respiration
nitrogen cycle
atmospheric N2 can’t be used, nitrogen fixation (N2 is converted into usable nitrogen compounds like ammonia and ammonium) by nitrogen-fixing bacteria and decomposers during ammonification), nitrification (bacteria converts NH3 and NH4 into nitrite and nitrate which are important for plant growth), denitrification (bacteria converts NO3 in the soil and water back into N2 and released into the atmosphere), emissions from industry and engines also release N2
sulfur cycle
sulfur is an important nutrient as it’s a component of amino acids and rocks, most are locked in the ground where O2 is scarce, is a byproduct of combustion which changes precipitation (acid rain); sulfur in fossil fuels, sediments, and other molecules is converted into sulphates in soil thru decomposition and microorganism, taken up by plants, sulphates in water undergo sulphate reduction in the ground which leads to the deposition of sulphides to sediment, combustion and mining also contributes sulfur oxides in the atmosphere
phosphorus cycle
key component of cell membranes and found in vital molecules including DNA, most is found in rocks, extraction for use as fertilizer can be washed into bodies of water that allow algae to grow which are toxic and contaminate water supplies and ecosystems, often accumulates in bottom of water bodies and can activate/feed the algae; organic decomposition of animal waste and decaying matter leads to marine sedimentation (build-up in the bottom) and production of dissolved phosphates, phosphates are taken in by plants, algae, and other photosynthetic organisms, erosion of phosphate rocks and extraction from mines leads to runoff in rivers and streams which are taken in by plants and are organically decomposed
