Ecological Factors(生态因子) Definition:Factors influencing the establishment,growth,and survival of the individual. >Abiotic Factors-all of the nonliving parts in an ecosystem (climatic,physiographic, edaphic土壤.) >Biotic Factors-all of the living factors in an ecosystem
Ecological Factors Ecological Factors (生态因子 ) Definition: Factors influencing the establishment, growth, and survival of the individual. ¾Abiotic Factors- all of the nonliving parts in an ecosystem (climatic, physiographic, edaphic土壤.) ¾Biotic Factors-all of the living factors in an ecosystem
Ljebig's law of the minimum 李比西最小因子定律 Justus Leibig (1840)-plant nutrients and growth Liebig's law of the minimum -production of an organism is limited by that substance which is in least supply relative to the demands of the organism 植物的生长取决于数量最不足的那一种营养元素。这种元素不 但直接限制植物生长，同时也会限制其他因子的效应
Justus Leibig (1840) - plant nutrients and growth Liebig's law of the minimum - production of an organism is limited by that substance which is in least supply relative to the demands of the organism 植物的生长取决于数量最不足的那一种营养元素。这种元素不 但直接限制植物生长，同时也会限制其他因子的效应。 Liebig ‘s law of the minimum of the minimum 李比西最小因子定律 李比西最小因子定律
Liebig used the image of a barrel- now called Liebig's barrel(木桶) The capacity of the barrel is limited by the length of its shortest stave(窄板) The yield potential of a crop is like a barrel with staves of unequal length. When that stave is lengthened. another one becomes the limiting factor
• Liebig used the image of a barrel— now called Liebig‘s barrel （木桶） • The capacity of the barrel is limited by the length of its shortest stave (窄板） • The yield potential of a crop is like a barrel with staves of unequal length. When that stave is lengthened, another one becomes the limiting factor
Some subsidiary补充principles 1.Organisms may have a wide range of tolerance for one factor and a narrow range for another. 2.Organisms with wide ranges of tolerance for limiting factors are likely to be most widely distributed. 3.When conditions are not optimal for a species with respect to one ecological factor,the limits of tolerance may be reduced for other ecological factors
Some subsidiary Some subsidiary 补充 principles principles 1. Organisms may have a wide range of tolerance for one factor and a narrow range for another. 2. Organisms with wide ranges of tolerance for limiting factors are likely to be most widely distributed. 3. When conditions are not optimal for a species with respect to one ecological factor, the limits of tolerance may be reduced for other ecological factors
Some subsidiary principles 4. Organisms in nature are not actually living at the optimum range of a particular physical factor. 5.Reproduction is usually a critical period when environmental factors are most likely to be limiting. 6.Factor Compensation
Some subsidiary principles Some subsidiary principles 4. Organisms in nature are not actually living at the optimum range of a particular physical factor. 5. Reproduction is usually a critical period when environmental factors are most likely to be limiting. 6. Factor Compensation