LIMITING FACTORS

A VARIETY OF ABIOTIC FACTORS AFFECT THE NUMBER OF ORGANISMS IN A POPULATION. A GIVEN SPECIES CAN SURVIVE AND GROW ONLY IF THE FACTORS FALL WITHIN A RANGE TOLERATED BY THE SPECIES. FOR EXAMPLE, AN ORGANISM MAY ONLY TOLERATE BY THAT SPECIES. FOR EXAMPLE, AN ORGANISM MAY ONLY TOLERATE A SPECIFIC TEMPERATURE RANGE.

AGAIN, IN A GIVEN SITUATION, ONE FACTOR MAY BE MORE IMPORTANT IN REGULATING THE POPULATION GROWTH OF A SPECIES THAN OTHER FACTORS. SUCH A FACTOR IS CALLED A LIMITING FACTOR. FOR EXAMPLE, A PLANT MAY NEED JUST THE RIGHT AMOUNT OF RAINFALL----NOT TOO LITTLE AND NOT TOO MUCH.

THE LIMITING FACTOR PRINCIPLE IS AS FOLLOWS : -

TOO MUCH OR TOO LITTLE OF AN ABIOTIC FACTOR CAN LIMIT OR PREVENT THE GROWTH OF A POPULATION, EVEN IF ALL OTHER FACTORS ARE AT THE REQUIRED RANGE OF TOLERANCE.

SOME OF THE LIMITING FACTORS IN TERRESTRIAL ECOSYSTEMS ARE : -

• RAINFALL OR PRECIPITATION
• TEMPERATURE
• MICRO NUTRIENTS

IMPORTANT LIMITING FACTORS FOR AQUATIC  ECOSYSTEMS ARE : -

• WATER TEMPERATURE
• SUNLIGHT
• DISSOLVED OXYGEN CONTENT
• SALINITY