ENERGY IN ECOSYSTEMS Flashcards
what is a ecosystem? (1)
a community of living organisms in conjunction with the non-living components of their environment, interacting as a system.
what are edaphic factors? (1)
the nature (structure and composition) of the soil itself.
what is a population? (1)
all of the individuals of one species in an environment or habitat at the same time that interest.
what do segments on the population of individuals graph represent? (4)
A=lag phase
B=log phase
C=stationary
D=death phase
what is the lag phase? (1)
rate of growth is slow due to acclimatation to surroundings.
what is the log phase? (1)
plenty of food and shelter therefore very little competition also known as the exponential growth phase.
what is the death phase? (1)
deaths increase and reproduction rate decreases because competition for resources. deaths can also occur due to toxins produced by population.
how might a population interaction? (4)
-mating
-competition for food and shelter
-protection/parenting
-social living
what is a community? (1)
all of the organisms of all species living in the habitat, environment at the same time that they interact.
how might different species interact? (2)
-competition food/space
-predator/prey/herbivores
what is the carrying capacity? (1)
the maximum stable population that an ecosystem can support.
what are density dependent factors? (1)
a factor that is dependent on the population
what are density independent factors? (1)
a factor that is not dependent on the population.
what is meant by biota? (1)
all of the living things found within an ecosystem.
what do biotic factors relate to? (3)
-climate
-soil
-topography
what factors are involved within the climate? (1)
factors such as solar radiation, temperature, rainfall, etc
what factors are involved in soil? (1)
parent rock, soil water and soil chemistry (edaphic factors).
what factors are involved in topography? (1)
slope and aspect of the land, and altitude.
how does sun light effect an ecosystem? (1)
is a major source of heat - very few organisms grow if the temperature of their environment falls outside of the range of 0-4o degrees. temperature rate influences the rate of all biochemical reactions.
what effect might low temperature have on an ecosystem? (1)
ice crystals may form in cells, disrupting the cytoplasm.
what effect might high temperature have on an ecosystem? (1)
denaturation of enzymes
what effect does light intensity have on an ecosystem? (1)
affected by factors such as latitude, season, aspect (slope), time of day and the extent of cloud cover.
how does relative humidity effect the ecosystem? (1)
influences rate of water loss by evaporation and on rate of transpiration.
how does the soil pH affect an ecosystem? (1)
affects the availability of nutrients and otherwise exist in other forms
how does soil temperature affect an ecosystem? (1)
affects root growth, microorganisms activity and seed germination.
how does soil texture affect an ecosystem? (1)
relative proportions of different sized particles affect (aeration/drainage)
how does slope/aspect effect an ecosystem? (1)
indirect effects on illumination etc
how does terrestrial/pond water supply of flow have on an ecosystem? (1)
pons with spring source are permanent with relatively stable communities, whereas pons raised by surface drainage tend to have ephemeral communities
what effect does oxygen availability have on an ecosystem? (1)
low or non-existent concentrations of oxygen trigger anaerobic respiration and favour obligate anaerobic organisms.
how are climatic factors measured? (3)
dedicated digital sensor linked to a sensor meter
permanently mounted maximum and minimum thermometer
whirling hygrometer
how are edaphic factors measured? (3)
dedicated digital sensor linked to a sensor meter
calorimetrical measurement using a soil test kit
hand assessment of soil
how are topographical factors measured? (3)
survey methods (profile transect)
measurements of seasonal changes in water levels
dedicated digital sensor linked to a sensor meter
what is a predator? (1)
an organism that feeds on other living species
what is grazing? (1)
the eating of plants by herbivores
what is meant by symbiosis? (1)
a close and often obligatory association between two or more organisms often, but not necessarily to mutual advantage
what is parasitism? (1)
a mutualistic partnership between two living organisms where one partner gains benefit and the other does not.
what are the types of parasite? (1)
endoparasites and edoparasites
what are endoparasites? (1)
live in the body of their host
what are edoparasites? 91)
live on the body of their host
what is an autotroph? (1)
an organism capable of making its own food source (complex organic compounds) from inorganic molecules
what are the types of autotrophs? (2)
photoautotrophs and chemoautotrophs
what is an heterotroph? (1)
organisms that need to consume other organisms for food( complex organic molecules)
