ECOLOGY. ECOLOGY. The study of the relationships of organism with each other & their environment. The term environment refers to the external conditions in which the organism or the biotic and abiotic factors. Abiotic factors – refers to non-living things or physical factors
Ecosystem – a distinct, self-supporting system of organisms interacting with each other & their physical environment e.g. a pond, a mangrove swamp.
Species population community ecosystem
Sunlight – E used comes from sun. Needed for photosynthesis. Affects distribution of species
Temperature- most organism live in narrow range of temperature. Affects distribution.
Humidity – organisms need a certain level of moisture in the air
Water-needed for survival e.g. cell function. Salinity levels vary this affects distribution & osmoregulation of some species
Soil – plants depend on soil while animals depend on plants. Survival impossible if soil is too acidic or alkaline
Wind – helps disperse plant seeds. However, strong winds makes survival difficult
O2– needed for respiration & other metabolic functions. More O2 is present in flowing water than stagnant pools
A – New pop’n of bacteria grows slowly at 1st. Although reproduction occurs the total # doesn’t increase quickly
B – with no limiting factors, pop’n grows at rapid rate, doubling over time
C – limiting factors affect pop’n, reproduction rates slow down preventing increase in numbers
D – death of bacteria
ANIMATION - http://www.epa.gov/climatechange/kids/global_warming_version2.html
The purple-blue in this picture is the hole in the ozone layer over Antarctica
How Ozone Depletion Affects UV Levels
In 2001, it is reported that each person has a G.F. of 2.2 ha (took 2001 world pop’n no.) i.e. we are using 21% more than the Earth can provide & sustain.
Recycling – means treating used objects so that they can be used again