Exponential growth - the unrestricted increase in a population (also called the biotic potential of a population) - J-curve
Carrying capacity - the maximum number of individuals of any species that can be supported by a particular ecosystem on a sustainable basis
Potential growth of a population over time. Exponential growth and then reaching carrying capacity. Carrying capacity may not be well defined because of changes in the environment over time. Variations in the environment – drought, f.e., can actually change the carrying capacity. As seen in the graph, a population might overshoot its carrying capacity, drop below the average, and then increase and overshoot it again.
Dieback – отмирание; overshoot – перелет
Community Properties
Environmental resistance - factors that tend to reduce population growth rates:
may depend or not on pop density
• Primary productivity - a community's rate of biomass production, or the conversion of solar energy into chemical energy stored in living (or once-living organisms)
• Net primary productivity - primary productivity minus the energy lost in respiration
• Productivity depends on light, temperature, moisture, and nutrient availability.
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