Bakus, G.J.; Hajdu, E.; Pinheiro, U.S.; Nishiyama, G. (2004). Density measurements for biodiversity studies: the sponge Polymastia janeirensis (Boury-Esnault, 1973) from Brazil. In: Pansini M, Pronzato R, Bavestrello G, Manconi R, Sarà M (eds) Sponge Science in the New Millenium. Bollettino dei Musei e degli Istituti Biologici dell'Universitá di Genova. 68: 195-200.
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Bakus, G.J.; Hajdu, E.; Pinheiro, U.S.; Nishiyama, G.
2004
Density measurements for biodiversity studies: the sponge <i>Polymastia janeirensis</i> (Boury-Esnault, 1973) from Brazil. <i>In</i>: Pansini M, Pronzato R, Bavestrello G, Manconi R, Sarà M (eds) Sponge Science in the New Millenium.
Bollettino dei Musei e degli Istituti Biologici dell’Universitá di Genova
68: 195-200
Publication
Proceedings of the 6th International Sponge Conference Rapallo (Italy) 29 September – 5 October 2002.
Studies on the sponge Polymastia janeirensis (Boury-Esnault, 1973) were conducted at an average depth of 3 m on the southeast side of Praia Brava, Buzios, Rio de Janeiro, Brazil during March 4-6, 2001. The sponges measured an average of 17.5 cm x 23.9 cm (oval in shape) and their distribution was moderately aggregated (standardized Morisita Index: 0.49). Densities of P. janeirensis were determined using various methods. Density estimates were as follows: actual count 1.7/m2; stratified random sampling 5.8/m2; point center quarter 0.7/m2; 3rd nearest neighbor 1.6/m2; Weinberg 1.2/m2; Strong-Eberhardt 2.0/m2; and Nishiyama medium 1.1/m2. The method tentatively recommended for estimating densities is the 3rd nearest neighbor, based on preliminary results from this study and other research projects.
South Atlantic
Spacial and ecological distribution, Zonation, Microdistribution