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Liebig proposed that too little of something can be alimiting factor. but too much of certain substance may also act as a limiting factor. thus organism have an ecological minimum and maximum limit of tolerance the range in between is called the limits of tolerance.
the concept of limiting effect of maximum as well as minimum constituents is included in shelford law of tolerance(Shelford 1913).
All physical requirements may be well within the limits of tolerance for an organism, but the organism may fail due to biological interrelations such as competitions and the predations.............
some subsidiary principles to law of tolerance may be ststed as follows:
1. organisms may have a wide range of tolerance for one factor and a narrow rangw for the other.
2. organisms with side range of tolerance for limiting factors are likely to be most widely distributed.
3. in some cases whwn conditions are not optimal for a spedies with respect to one ecological factor then the kimits of tolerance may be reduced for other ecological factors.
4. sometimes it may happen that an organism may not be living at the optimum range of a particular factor. in such cases the othes physical factors are founf to have great importance.
ex: the cord grasses which dominates the east coast salt marsh areas, actually grows better in fresh water than in salt water. but in the nature it is found in only salt water, apparently because it can extrude salt from leaves better than any of its competitors.
5. the limits of tolerance for reproductive individuals, seeds, eggs , embryo etc are usually nonreproducing individuals.... ex: an adult cypress tree will grow continually submerged in water or dry upland, but it cannot reproduce untill there is moist unfloded ground.
download in .pdf format
Liebig proposed that too little of something can be alimiting factor. but too much of certain substance may also act as a limiting factor. thus organism have an ecological minimum and maximum limit of tolerance the range in between is called the limits of tolerance.
the concept of limiting effect of maximum as well as minimum constituents is included in shelford law of tolerance(Shelford 1913).
All physical requirements may be well within the limits of tolerance for an organism, but the organism may fail due to biological interrelations such as competitions and the predations.............
some subsidiary principles to law of tolerance may be ststed as follows:
1. organisms may have a wide range of tolerance for one factor and a narrow rangw for the other.
2. organisms with side range of tolerance for limiting factors are likely to be most widely distributed.
3. in some cases whwn conditions are not optimal for a spedies with respect to one ecological factor then the kimits of tolerance may be reduced for other ecological factors.
4. sometimes it may happen that an organism may not be living at the optimum range of a particular factor. in such cases the othes physical factors are founf to have great importance.
ex: the cord grasses which dominates the east coast salt marsh areas, actually grows better in fresh water than in salt water. but in the nature it is found in only salt water, apparently because it can extrude salt from leaves better than any of its competitors.
5. the limits of tolerance for reproductive individuals, seeds, eggs , embryo etc are usually nonreproducing individuals.... ex: an adult cypress tree will grow continually submerged in water or dry upland, but it cannot reproduce untill there is moist unfloded ground.
download in .pdf format
