Bio2129 topic 4/5
what are the major physical protorties of terrestrial ecosytems
clilmate, water, nutrients and substrate
what is climate
long term temperature, preticipattion and wind patterns. determines biome distrobution
what are nutrients
they are essential elements for plant growth and their distrobution effects productivity
what are substrates
physical base like soil or rocks. soil types fertility, ph and drainage control what organisms can grow
Sunlight strikes the earth differently depending on
latitude
along the equator the sunrays strike
at a higher angle, it is a smaller area and more concentrated therefore hotter
sunlight strikes the poles and hits
at a lower angle, it is spread out ove a alrge area therefore colder
what is temperature gradient
the variation in heat inputs that set up predictable climate zones
why is temperature gradient important
1) Shapes biomes, allows us to see predictable distrobution of ecosystems. 2) Controls energy availability, Temperature comes from solar rediation concentration which drives photosynthesis ( areas with higher sunlight, like the equator, supports higher productivity. Colder regions ( poles and high mountains) have shorter growing season=lower productivity. 3) determines species distrobution, every species has a thermal tolerance and temperature range where it can survive and reproduce. also sets boundires for wher organisms can live
what are seasons caused by
the earth's tilt (23.5), which changes the solar input throughout the year
What is global circulation
the worldwide movement of air and indirectly water, caused by the uneven heating of the earth's surface by the sun and earth's rotation
what does it mean when we say global circulation has unequal heating
the equator gets the most direct solar energy and hot, moist air rises
what are hadley cells
circulation cells from 0-30 latitude where warm, moist air rises at the equator which causes a heavy rainfall and tropical rainforests, then sinks dry at 30 which creates deserts. ( desending poleward)
what are Ferrel cells
circulation cells from 30-60 latitude, driven by intercations between hadley and polar cells producing temperature climates with moderate rainfall, specific season and variable weather
ferrels cells are not driven by
temperature
what are polar cells
circulation cells from 60-90 latitude where cold, dry air sinks at the poles which makes cold, low precipitation environments likes tundra and polar deserts
what are prevailing winds
the dominant global wind patterns that are formed by circulation cells and the earth's rotation that continously move air in specific direction.
examples of prevailing winds
trade winds, westerlies and polar easterlies
what is the coriolis effect
it causes the deflections of winds clockwise (high pressure) in the north hemisphere and counterclockwise (low pressure) in the south hemisphere
the coriolos effect influences
global wind patterns, ocean currents and climate regulation.
due to earth rotation what is faster equator or poles
the equator is faster since it is wider than that the poles
what is global temperature variability
different parts of the globe have different seasonal differences. larger difference with areas that have hot summers and cold winters. smaller differences in coastal/oceanic areas, with more stables and elss seasonal changes
what is the orographic effect (mountain influence on climate)
when moist air comes inland from the ocean and hits a mountain range, it has no choice but to rise up the slope
what is windwardside and how does get effected orographically
The side facing the ocean/wind. As the air rises, it expands and cools, cooler air cant hold as much moistures so water vapor condenses, producing clouds and precipitation (rain or snow) which results in a wet, lush environment like a temperate rain forest
what is the Leeward side and how is it effected orographically
The downwind, away from the ocean. After the air loses its moisture, it descends on the other side of the mountain. descending air warms and becomes very dry. resulting in arid conditions (rain shadow desert)
what is a biome and how does climates affect vegetation
biomes are large scale ecological communites were climate ( temperature and precipitation) determines the vegetation, which then determine the species that can survive there.
what is primary productivity
the rate at which plants convert solar energy into chemical energy through photosynthesis. It determines the base of foodwebs and how much energy is available for higher trophic levels
what is net primary productivity
the energy that's left after plants use some of the energy for respiratin. represents the energy available for herbivores and decomposers.
the higher the net primary productivity, the more...
the biomass and more species are supported
what are some limitng factors of primary productivity
Temperature, water and radiation
what effect does temperature have as a limiting factor in primary productivity
warmer climates mean higher ensymatic activity and photosynthesis. Lower temperatures (tundra) shorten growing seasons and extreme heat can cause droughts/stress
what effect does water have as a limiting factor in primary productivity
it is essential for photosythesis and nutrient transport in plants. higher rainfall = lush vegetation (rainforests). Low rainfall = deserts with very low productivity. water availability interacts with temperature. (hot + dry = strong limitations)
what effect does solar energy radiation have as a limiting factor in primary productivity
more sunlight = more energy for photosythesis. Cloud cover/ high altitudes reduce solar input and strongy effects productivity.
what are some ecological consequences of net primary productivity
High NPP= dense plant growth, high biomass, more resources for herbivores and canivores = higher biodiversity (tropics). Low NPP= spares vegetation = limited resources, fewer species are supported (deserts, tundras and polar regions)
what are global ocean currents (thermohaline circulation)
The global mouvement of ocean water diversity by temperature and salinity differences.
why are global ocean currents (thermohaline circulation) important
it regualtes global climate by transporting heat and circulates nutrients and oxygen, supporting marine ecosystems
why is global ocean circulation sensitive to change
because warming and melting ice can reduce salinity and density which slows currents and impacts climate
why are some areas of marine primary productivity more productive
1) light availability, algae and phytoplankton can only live near the surface, where sunlight hits so they can photosynthesis. deep water has no light therefore no photosynthesis can occur. 2) Nutrients, high productivity near coast and upwelling zones where currents bring nutrient rich water to the surface.
why do poles usually have more nutrients than the equator
poles have strong upwelling + seasonal sunlight whihc produces high productivity in the summer. Equator has lots of sunlight, but productivity is limited beacuse nutrients are scares since in tropical regions they get taken by plants for NPP, leaving very little available in the water column
what do climate diagrams do
summarize climatic info using standardized structure
what do climate diagrams look like
temperature on left vertical axis, precipitation on right vertical axis, all 12 months on bottom horazontal axis. 10C to 20mm precipitation plotting. precipitatin blue (usually higher than temp) and temp red.
why are global soil regions important
nutrients in soil determine ecosystem functions. what plants grow, what animals are supported and overll biodiversity.
what does it mean when it says soil is linked to climate
rain and temperature control soil development. more precipiation= more nutrients are washed away.
nutrient poor soil poor for agriculture is found in
wet tropics (oxisols)
what are temperate soils (mollisols, alfisols)
rich and fertile soil good for agriculture (prairies and grassland)
what are Arid soilds (aridisols)
low organic matter and limited productivity. (deserts)
what are human impacts on global soil regions
agriculture exports nutrients from soil and causes shifting cultivation
what is shifting cultivation
when land is burned, nutrients temporarily return to the soil, which allows crops to grow, but after repeated use nutrients are exhausted and land needs to be left to recover
why is substate important
local soil and water conditions make ecological communities
what is topography (slope and aspect)
the direction a slope faces (aspect) changes how sunlight is exposed and affects temperature and moisture