biological productivity

• what is meant by biological productivity


  this is the rate at which biomass accumulates in a ecosystem
• what is meant by biomass


  this is the dry weight of organic matter
• what is meant by NPP


  this is the rate at which producers convert energy into biomass
• what is the formula that links food eaten , energy in faeces and respiration together


  (food eaten - energy in faeces )-respiration
• what is meant by primary productivity


  the production of new organic matter by green plants
• what is meant by secondary productivity


  this is the rate at which consumers accumulate energy from assimilated food in biomass in their cells of tissues
• why do herbivores have a lower secondary productivity than carnivores


  protein is more rapidly and easily digested then cellulose . a lot of cellulose is lost in the faeces of a herbivore
• explain why farmers keep animals in barns during the winter

  to reduce the amount of energy lost during respiration so more energy is available to produce biomass
• what are the three reasons why energy is lost between each trophic level


  energy in egested molecules , energy lost as heat generated in respiration and energy remain in inedible parts of animals