unit D ecosystems and population change (part one)

ecology is the study of interactions between organisms and their environment.

abiotic factors are non-living factors that influence organisms

biotic factors are the living factors that influence an organism

organism do not usually live in isolation but in a group of the same species in a population.

if there is more them on species in an ecosystem it is known as an community

general sequence of ecology→ organism→ population→ community→ ecosystem

the transition area in which animals can move through ecosystems in called the ecotone

ecosystem with a higher biodiversity are more stable then those with a low biodiversity

extirpated means that the organism is only found in some places of the world but is extinct from others

niche is the organism role in the ecosystem

if a new species were to enter an ecosystem it would cause a disturbance causing competition between niches. the introduction of a exotic species may happen naturally with the movement or organisms

the introduction of new species can lead to extinction due to the fact that they have lost their habitat

if the new introduces species is a preditor they prey may no have a defense mechanism

if this species begins to take of the environment it is knows as an invasive species

ecosysems’s are smaller regions within the biosphere

biomes are large geographical regions within a specific climate and certain organisms have adapted to there own biomes

terrestrial ecosystems can be found any where on earth and are not covered in water Canada consists of 2 major biomes boreal forest and grassland

aquatic ecosystems can be divided into three zones: littoral zone which is an area where there is plant growth because sunlight is able to reach it, limnetic is an open area with just enough sunlight for photosynthesis to occur, and profundal zone does not have enough sunlight for photosynthesis

biotic and abiotic factors can effect ecosystems: abiotic factors that may effect terrestrial ecosystems are soil, available water, tempter, and sunlight

soil is viewed as a series of layers litter, then top soil, then subsoil, and the bottom layer is bedrock

there are 4 main abiotic factors that affect aquatic environments: chemicals environments, salt vs. fresh water, ph., temp and available sunlight, less organisms supported in cold water, water pressure, seasonal changes

biotic potential id the organisms maximum number of offspring that a species could produce if there was unlimited recourses

<<there are four factors that regulate biotic potential: birth potential, capacity for survival, breeding frequency, length of reproductive life.<< birth potential is the maximum number of offspring per birth

capacity of survival is the number of offspring that reach reproductive age

breeding frequency is the amount of times an organism is able to breed during a year

length of reproductive life is how long an animals life is where they are able to reproduce

limiting factors prevent organisms from reaching there biotic potential

abiotic factors: sunlight, temp, chemical environment

biotic factors: food, predictors, disease, competition for recourses

carrying capacity is the maximum number of individuals of a species that can be supported by an ecosystem

density dependent factors: a factor that affects members of a population because of the population density. example food, disease, exotic species, increased predation competition

density independent factors effect a population regardless of the populations density- natural disaster

slash and burn is the complete clearing of a forest by burning trees

clear cutting is the removal of all trees in an area for timer

selective cutting is the cutting of only certain trees leaving the others to regenerate the area.

a prescribes burn is a controlled fire set intentionally in a designated area

oligotrophic is low in nutrients and eutrophic is high in nutrients

water pollution can be broken into five groups: organic soil waste, disease causing organisms, inorganic solids, thermal energy from electricity, and organic compounds

there are three main indicators of water quality; bactiria count, diseased oxygen, examine living things in the water.