RT master thesis
T1 Propiedades ópticas y teledetección de macrófitos marinos en la  Bahía de Cádiz, España
T2 Optical properties and remote sensing of marine macrophytes within  Cádiz Bay, SW Spain
A1 Gómez-Ordonez, Eva
A2 Biología
K1 Macrofitos
K1 Teledeteccion
K1 Quickbird
K1 Reflectancia
K1 RNM-214
K1 Atenuacion
K1 Remote sensing
K1 Reflectance
K1 Macrophytes
K1 Attenuation
AB The optical properties of marine macrophytes within Cádiz Inner Bay (Cymodocea nodosa, Zostera marina, Zostera noltii and Caulerpa prolifera) were examined in detail. C. prolifera had a higher total absorption and specific absorption than the seagrass species, suggesting the macroalgae was more efficient at capturing light. In the field, in situ reflectance (R) spectra of different intertidal biotopes were investigated. R spectra of ‘bare’sediment suggested the presence of benthic microalgae. Differences were observed between bare sediment and macrophyte R spectra. Changes in R related to increasing % cover of seagrasses could be easily summarised using the normalised difference vegetation index(NDVI). In order to examine the effect of the water column, we logged bottom reflectance during the incoming tide and calculated the effective attenuation of light. This calculation was repeated using radiance values extracted from the remote sensing image in an area where the depth was know in detail. Red and near infra-red light was attenuated more strongly than blue or green, except in areas with high turbidity. Rearrangement of the equations describing attenuation through the water column, allowed us to derive a prediction of the water depth throughout the rest of the image. In shallow areas variation in turbidity, bottom type and optical effects, and in deep areas, high turbidity limited the application of the model. Using the depth prediction and the calculated attenuation coefficients we were able to correct the majority of the image for the influence of water-column attenuation. The corrected image was classified using the reflectance spectra of different biotopes, to produce a first approximation of the spatial distribution of benthic macrophytes within Cádiz Inner Bay. In conclusion, remote sensing appears to be a promising technique for the mapping of marine macrophytes within shallow, intertidal systems such as Cádiz Bay.
YR 2011
FD 2011-07-14T00:00:00Z
LK http://hdl.handle.net/10498/14121
UL http://hdl.handle.net/10498/14121
LA spa
NO Esta investigación ha sido financiada por el proyecto de excelencia FUNDIV P07-RNM-02516, cofinanciado por la Junta de Andalucia y la Unión Europea (fondos FEDER) y el proyecto Nacional EVAMARIA CTM 2005-00395), cofinanciado por el Ministerio de Ciencia y Tecnología y la Unión Europea (fondos FEDER). Agradecemos a Dr. Alfonso Corzo su colaboración para el uso de material de laboratorio.
DS Repositorio Institucional de la Universidad de Cádiz
RD 06-nov-2026