ABSTRACT
Rotifer production in a shallow artificial lake (Lobo-Broa Reservoir) was studied for twenty consecutive days between August 25, 1995 and September 13, 1995, during the dry season. Two species were dominant, during this period namely Filinia pejleri and Keratella americana, contributing, respectively, 36% and 28% to total rotifer numbers. Production estimates of these species were, respectively, 41.93 and 80.70 µg dry weight.m-3.d-1, corresponding to 18.45 and 35.51 µgCm-3.d-1. The population of F. pejleri was numerically more abundant than that of K. americana, while the production of the former was less, as a result of lower egg to female ratios.
A produção de rotíferos da Represa do Lobo-Broa foi estudada durante o período de vinte dias consecutivos, no inverno (25/8/95 a 13/9/95). Amostragens diárias foram efetuadas com a finalidade de conhecer a influência das condições físicas e químicas do ambiente na dinâmica das populações de Rotifera em um curto intervalo de tempo. Duas espécies dominaram nesse período: Filinia pejleri e Keratella americana, as quais contribuíram com 36% e 28%, respectivamente, do total da densidade de Rotifera. A produção secundária dessas espécies foi calculada em 41,93 µgPeso-Seco.m-3.d-1 e 80,70 µgPeso-Seco.m-3.d-1, correspondendo a 18,45 e 35,51 µgCm-3.d-1, respectivamente. A população de F. pejleri foi mais abundante que a população de K. americana, porém, sua produção foi menor, devido a sua baixa razão ovo/fêmea.
ABSTRACT
Rotifer production in a shallow artificial lake (Lobo-Broa Reservoir) was studied for twenty consecutive days between August 25, 1995 and September 13, 1995, during the dry season. Two species were dominant, during this period namely Filinia pejleri and Keratella americana, contributing, respectively, 36 percent and 28 percent to total rotifer numbers. Production estimates of these species were, respectively, 41.93 and 80.70 µg dry weight.m-3.d-1, corresponding to 18.45 and 35.51 µgCm-3.d-1. The population of F. pejleri was numerically more abundant than that of K. americana, while the production of the former was less, as a result of lower egg to female ratios