Effect of salinity and food concentration on competition between Brachionus plicatilis Müller, 1786 and Brachionus calyciflorus Pallas, 1776 (Rotifera)
Por:
Ferrando, N. S., Nandini, S., Claps, M. C., Sarma S.S.S.
Publicada:
1 ene 2020
Resumen:
Natural populations of planktonic rotifers are affected by salinity and food density, among other stressors. Moreover, competition among congeneric species limits the abundance of certain rotifers in ecosystems without spatial heterogeneity and environmental fluctuations. We isolated Brachionus plicatilis and Brachionus calyciflorus from Salado River basin waterbodies and studied the demographic characteristics and competition between them at three salinity levels (0.75, 1.75 and 2.75 g L-1 NaCl) and at two food concentrations (0.1 × 106 and 0.5 × 106 cells mL-1 Chlorella vulgaris). The lowest salinity level proved to be unfavourable for the population growth of B. plicatilis, but at higher salinity levels the growth was similar to that of controls (without competition), even in the presence of the competitor and at either food concentration. By contrast, the competitor almost always decreased the density of B. calyciflorus. Salinity greatly affected the peak density of B. plicatilis, whereas the effects of salinity and competition on B. calyciflorus were similar. Biomass was inversely related to salinity for both species, and was significantly affected by competition in B. plicatilis. These results show that B. calyciflorus is more adversely affected than B. plicatilis by competition and high salinity, and explain why both species can coexist in eutrophic saline lowland rivers and pampean shallow lakes. © 2020 CSIRO.
Filiaciones:
Ferrando, N. S.:
Instituto de Limnología Dr Raúl A. Ringuelet, Boulevard 120 y 62, La Plata, Provincia de Buenos Aires, 1900, Argentina
Univ Nacl La Plata, Consejo Nacl Invest Cient & Tecn, Inst Limnol Dr Raul A Ringuelet, Blvd 120 & 62, RA-1900 La Plata, Buenos Aires, Argentina
Nandini, S.:
Laboratorio de Zoología Acuática, Edificio Unidad de Ciencias Morfologicas Universidad Nacional Autonoma de Mexico, Campus Iztacala, Avenida de los Barrios 1, Los Reyes, Estado de México CP, 54090, Mexico
Univ Nacl Autonoma Mexico, Lab Zool Acuat, Edificio Unidad Ciencias Morfol, Los Reyes 54090, Estado De Mexic, Mexico
Claps, M. C.:
Instituto de Limnología Dr Raúl A. Ringuelet, Boulevard 120 y 62, La Plata, Provincia de Buenos Aires, 1900, Argentina
Univ Nacl La Plata, Consejo Nacl Invest Cient & Tecn, Inst Limnol Dr Raul A Ringuelet, Blvd 120 & 62, RA-1900 La Plata, Buenos Aires, Argentina
Sarma S.S.S.:
Laboratorio de Zoología Acuática, Edificio Unidad de Ciencias Morfologicas Universidad Nacional Autonoma de Mexico, Campus Iztacala, Avenida de los Barrios 1, Los Reyes, Estado de México CP, 54090, Mexico
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