2000
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Interciencia
Elizabeth Olivares et al., « Salinity gradient in the mánamo river, a dammed distributary of the Orinoco Delta, and its influence on the presence of eichhornia crassipes and paspalum repens », Interciencia, ID : 10670/1.uei1i0
"We describe a saline gradient established by the dammingof the Mánamo River, a former freshwater environment, in theOrinoco Delta and the influence of this gradient on the distributionof Eichhornia crassipes Solms (water hyacinth), andPaspalum repens Berg, the two most abundant aquatic macrophytes.The present work demonstrates, on the basis of measurementsof leaf osmolality and ion concentrations, that salinity isacting in the dammed river as a regulator of the studied species.E. crassipes is a potential weed which was originally controlled by the hydrodynamics of waters in the Orinoco River.Plants and river water were sampled in ten sites, three of themwith high salinity. The osmolality as well as relative proportionsof the main soluble ions explain the relative tolerance to salinityof E. crassipes in comparison with P. repens. In sites where bothspecies were present, the K+/Na+ ratio in the leaf sap washigher in E. crassipes than in P. repens."