Effects of the intense summer desiccation and the autumn filling on the water chemistry in some Mediterranean ponds

The objective of this research was to compare the effects of evaporation and total desiccation, as well as the infiuence of the rate of refilling, on the concentrations of major ions and nutrients (nitrogen and phosphorus) in Mediterranean ponds. Water level fiuctuations in these ecosystems can have...

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Detalles Bibliográficos
Autores: Fernández-Aláez, Margarita|||0000-0003-3847-6613, Fernández-Aláez, Camino|||0000-0001-9385-1354
Tipo de recurso: artículo
Fecha de publicación:2010
País:España
Institución:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:ddd.uab.cat:80012
Acceso en línea:https://ddd.uab.cat/record/80012
Access Level:acceso abierto
Palabra clave:Llacunes
Composició iònica
Nutrients
Hidroperíode
Evaporació
Emplenat
Ponds
Ionic composition
Hydroperiod
Evaporation
Refilling
Lagunas
Composición iónica
Nutrientes
Hidroperiodo
Evaporación
Llenado
Descripción
Sumario:The objective of this research was to compare the effects of evaporation and total desiccation, as well as the infiuence of the rate of refilling, on the concentrations of major ions and nutrients (nitrogen and phosphorus) in Mediterranean ponds. Water level fiuctuations in these ecosystems can have a decisive role in community structuring and functioning and may affect their conservation values. The results obtained enable an assessment of the consequences of water quality changes resulting from the increased evaporation, drastic fiuctuations in water levels and higher incidence of droughts in summer. Desiccation was observed to cause an increase in the bicarbonate and chloride concentrations, whilst sulphate content was frequently found to have decreased. With respect to nutrients, a drastic reduction in water volume increased orthophosphate levels, with a consequent drop in the N-nitrate: SRP ratio. Pond refilling following total desiccation resulted in higher total anion content, especially among the waters with higher mineral content, the extent of which was related to the rate of refilling. When refill followed desiccation, sulphate concentrations increased the most, whilst alkalinity decreased in most ponds. An increase in chloride concentration was only observed when refilling occurred slowly. Orthophosphate and nitrate concentrations increased at the start of the refilling period, although the most pronounced increase was in nitrate which, together with potassium, was probably washed into the ponds through soilleaching following autumn rainfall.