Decapod crustaceans are one of the dominant faunal components of most tropical streams. However, several aspects concerning their biology and ecology are poorly known, especially in intertropical Africa. The aim of th...Decapod crustaceans are one of the dominant faunal components of most tropical streams. However, several aspects concerning their biology and ecology are poorly known, especially in intertropical Africa. The aim of this study was to investigate the production of the atyid shrimps in Masanga Mabe, an equatorial lowland forest stream of Kisangani region. Samplings were undertaken biweekly from September 2000 to August 2003 with Surber net in four study sites. A total of 14,878 atyid shrimps specimens were sampled, measured for carapace length, weighted and identified. Atyid production was estimated by size frequency method according to sites （1, 2 and 3）. Atyid composition showed the existence of two species： C africana （Caridina africana） Kingsley 1882 and C togoensis （Caridina togoensis） Hilgendorf 1893. Specific production ranged from 1.35 g·DM·m^-2-year^-1 （grams dry mass per square meter per year） to 8.4 g·DM·m^-2-year^-1 for C. africana and 0.95 g·DM·m^-2-year^-1 to 4.55 g·DM·m^-2-year^-1 for C togoensis. Mean annual P/B ratios varied from 3.89 year1 to 4.37 year1 for C africana and from 3.83 year^-1 to 3.98 year^-1 for C togoensis.展开更多
文摘Decapod crustaceans are one of the dominant faunal components of most tropical streams. However, several aspects concerning their biology and ecology are poorly known, especially in intertropical Africa. The aim of this study was to investigate the production of the atyid shrimps in Masanga Mabe, an equatorial lowland forest stream of Kisangani region. Samplings were undertaken biweekly from September 2000 to August 2003 with Surber net in four study sites. A total of 14,878 atyid shrimps specimens were sampled, measured for carapace length, weighted and identified. Atyid production was estimated by size frequency method according to sites （1, 2 and 3）. Atyid composition showed the existence of two species： C africana （Caridina africana） Kingsley 1882 and C togoensis （Caridina togoensis） Hilgendorf 1893. Specific production ranged from 1.35 g·DM·m^-2-year^-1 （grams dry mass per square meter per year） to 8.4 g·DM·m^-2-year^-1 for C. africana and 0.95 g·DM·m^-2-year^-1 to 4.55 g·DM·m^-2-year^-1 for C togoensis. Mean annual P/B ratios varied from 3.89 year1 to 4.37 year1 for C africana and from 3.83 year^-1 to 3.98 year^-1 for C togoensis.
