ASSESSING THE EFFECTS OF ABIOTIC ENVIRONMENTAL-STRESS, ON POPULATION-GROWTH IN LUMBRICUS-RUBELLUS (LUBRICIDAE, OLIGOCHAETA)

A matrix model for the population dynamics of Lumbricus rubellus was f ormulated to assess the effects of abiotic environmental disturbances on the viability of the population. The population dynamic model is ba sed on a description of individual growth, reproduction and mortality, which is partly derived from a simple model for the energy budget of an individual. The use of the energy budget model allows us to establi sh causal relations between physiological influences of abiotic enviro nmental stress and population performance. Data on individual growth a nd reproduction (Ma, 1982, 1984) are used to parameterize the model. T he analysis shows that the length of the adult life span, and conseque ntly the growth rate from birth to adulthood, is of overriding importa nce for the performance of the population. (C) 1997 Elsevier Science L td.