Data/hora: 01/06/2024 02:33:02

Provedor de dados: | Institutional Archive of Ifreme (ArchiMer)
País: | France
Título: | Étude et modélisation des populations de macrophytes dans la lagune de Thau (Hérault, France)
Autores: | Plus, Martin.
Data: | 2001-01-24
Ano: | 2001
Palavras-chave: | Primary production; Light; Nitrogen; Nutrients; Mathematical model; Thau lagoon; Seagrass; Macrophytes; Production primaire; Lumière; Azote; Nutriments; Model mathématique; Thau; Phanérogames; Macrophytes.
Resumo: | The works carried out can be divided in three main lines : design and management of experimental studies on primary production processes, macrophyte spatial distribution study and development of macrophyte and seagrass numerical models.  In situ and in vitro experiments have been performed with the aim of studying the processes and the parameters involved in the photosynthesis-respiration system, as well as to establish the main biotic (self-shading effect, physiology of the photosynthesis, carbon, nitrogen and chlorophyll tissu contents) and abiotic (temperature, light and nutrients) factors controlling macrobenthic primary production. A seagrass ecosystem model based on nitrogen and oxygen fluxes has been developped. Model calibration and validation have been performed on in situ measurements for a 1-D system involving the water column (1.5 m depth) and the sediment. In summer the model shows that macrophytes contribute up to 80 % of total primary production in shallow areas. On the contrary, in winter, rainy events contribute to enhance the phytoplankton primary production up to 60 % of total production. Using existant cartographies as references, ten species have been chosen and a simplified macrophyte cartography is presented in order to be used as a base for the macrophyte model.These ten species have been inserted, as forcing variables, to a three-dimensional model coupling physical and biological processes for the whole lagoon. Several simulations with and without the macrophytes have permitted to characterize a highly structured pattern brought by the macrophytes to the lagoon nitrogen and oxygen cycles. Moreover, the macrophytes annual total production for the whole lagoon have been estimated and is about 10 700 tC, wich represents four times less than the phytoplancton
Tipo: | Text
Idioma: | Francês
Identificador: | http://archimer.ifremer.fr/doc/2001/these-6518.pdf
Editor: | Paris 6
Relação: | http://archimer.ifremer.fr/doc/00000/6518/
Formato: | application/pdf