Contributions to the knowledge of the phenology of flowering in wetlands of Berisso, Buenos Aires, Argentina

Abstract

Contributions to the knowledge of blooming fenology in wetlands of Berisso, Buenos Aires, Argentina. A study of the phenology of blooming was carried out in an area of wetlands of Berisso, Buenos Aires, Argentina. The composition of the vegetation and the analysis of season vegetation was studied by means of fortnightly visits to the site of study. Forty-nine families and one hundred and eighteen species of Angiosperms were recorded. The botanical families with a major wealth of species were Asteraceae, Fabaceae, Brassicaceae, Verbenaceae and in a decreasing order: Lamiaceae y Oleaceae. The reproductive period begins in July and the major floral offer occurs in the months of November and December. Events observed as a response to metheorological phenomenon are the extension of life cycle of herbaceous plants susceptible to freezing temperatures, the anticipation and the repetition of the blooming phase in herbaceous and woody species. According to data of the Servicio Meteorológico Nacional the average minimum temperature during the studied lapse (2016-2018) was of 12°C, recording an increase of 2°C, in relation to the period spanning from 1980 to the 31st december of 2016. Besides it was observed since last decade, the decrease in the number of days with freezing temperatures due to first frosts delay and decreasing in number of days with freezing temperatures along with episodes of asincronic termoperiodism.