FLORA AND VEGETATION OF THE REÑACA CREEK (CENTRAL, CHILE)

Abstract

Ruderal flora and vegetation on the urban sector of the Reñaca creek that crosses the homonymous resort in the V Region of Chile was studied. 44 vegetation samples using the Zürich-Montpellier approach were gathered. A total of 73 species integrate the flora, 63 species were found within the sampling units and 10 outside of them. The flora is dominated by foreign species. 47 species contribute to 76% of the total plant cover. The biological spectrum is dominated by perennial swampy herbs (helophytes) and annual weeds (terophytes). The most important species are Cotula coronopifolia, Apium nodiflorum, Polypogon australis, Scirpus americanus and Rorippa nasturtium-aquaticum. Most of the species are swampy plants growing on the riverside, 13 are halophytes on saltmarshes and only 12 species are aquatic plants. The heterogeneouos phytosociological table, was ordered in 4 plant associations: Polypogo-Cotuletum coronopifoliae, Veronico-Apietum nodiflorae, Scirpo-Cotuletum coronopifoliae and Nasturtio-Hydrocotyletum ranunculoidis. The first two are new for the Chilean vegetation. The flora of the Reñaca creek is compared with that of other creeks and lagoons of the central zone of Chile.