Lilian A. Krug

Universidade do Algarve | UALG · Centro de Investigação Marinha e Ambiental (CIMA)

The establishment of many non-indigenous species is primarily controlled by propagule pressure, local environmental conditions, and biological interactions. An introduction is doomed to fail if any one of these factors is unsuitable. A few Atlantic blue crab Callinectes sapidus Rathbun, 1896 specimens have been collected along a limited stretch of...

Environmental conditions throughout the world ocean are changing in response to fossil fuel emissions and greenhouse warming in the atmosphere. Climate change and high carbon dioxide levels in the atmosphere are causing a domino-like series of changes in ocean conditions, including increased temperature, decreased oxygen content and acidification....

Upwelling strongly influences the composition and dynamics of coastal communities by affecting species abundances, recruitment, dispersal and distribution. Coastal upwelling areas are key model regions to study the responses of coastal species to climate change because they are characterized by cooler water conditions and experience lower warming r...

Phytoplankton patterns, tightly linked to the dynamics of the ocean surface layer and its atmospheric forcing, have major impacts on ecosystem functioning and are valuable indicators of its response to environmental variability and change. Phytoplankton phenology and its underlying drivers are spatially variable, and the study of its patterns, part...

This study evaluated the impacts of submarine groundwater discharges (SGD) on a rocky intertidal community of South Portugal, during April-November 2011. Chlorophyll-a concentration was higher at the SGD site in respect to the Reference site. Epibenthic community structure differed between sites, with an increase in Chthamalus spp. and a decrease i...

The partition of surface ocean domains is a tool to assess its patterns and driving forces, ideally incorporating its dynamic nature. The area off Southwest Iberian Peninsula (SWIP), located between temperate and subtropical waters, includes oceanic and coastal domains affected by atmospheric and ocean circulation patterns, as well as coastal proce...

Phytoplankton, the dominant marine primary producers, are considered to be highly sensitive indicators of ecosystem condition and change. The southwest area off the Iberian Peninsula (SWIP, NE Atlantic) is located in a biogeographical transition zone between temperate and subtropical waters, and classified as being very vulnerable to climate change...

The ocean surface is organized into regions with distinct properties reflecting the complexity of interactions between environmental forcing and biological responses. The delineation of these functional units, each with unique, homogeneous properties and underlying ecosystem structure and dynamics, can be defined as ocean surface partitioning. The...

Global coral bleaching episodes as those reported in 1982-83 and 1997-98, showed significant intra-regional differences in intensity. These bleaching events are generally associated to climatic forcing, namely thermal anomalies triggered by El Niño events. Evidences show that regional scale environmental variability is one important component that...

Iberia Peninsula (IP) constitutes the northern sector of the Canary Current Upwelling System. This study analyses the influence of upwelling on phytoplankton variability over a 15-year time series (1998-2012) off southwestern IP. Three polygons were delimited within the study area: west (WC) and south (SC) coasts and Cape São Vicente (CSV), the inf...

The uptake of atmospheric carbon dioxide (CO2) into the mid-latitudes of the North Atlantic Ocean through the production of wintertime Sub-Tropical Mode Water (STMW) also known as Eighteen Degree Water (EDW) is poorly quantified and constrained. Nonetheless, it has been proposed that the EDW could serve as an important short-term sink of anthropoge...

The region off southwestern Iberia (NE Atlantic) encompasses a wide variety of oceanographic regimes, including differently (geographic) oriented coastal areas impacted by upwelling, riverine inputs and submarine groundwater discharge, submarine canyons and seamounts, and open ocean waters, thereby potentially promoting zone-specific phytoplankton...

The region off southwestern Iberia (NE Atlantic) encompasses a wide variety of oceanographic regimes, including differently (geographic) oriented coastal areas impacted by upwelling, riverine inputs and submarine groundwater discharge, submarine canyons and seamounts, and open ocean waters, thereby potentially promoting zone-specific phytoplankton...

The relation between climate variability and coral bleaching in the Bahia reefs was investigated in an attempt to characterize the bleaching environments. The following 13-year time series were derived from the remote-sensing, analysis and reanalysis data: maximum summertime sea surface temperature (SST), maximum sea surface temperature (MaxSST) ac...

Ocean colour orbital sensors can collect information of the first quarter of the photic zone depth. This study proposed to calculate the chlorophyll-a concentration for this penetration depth and to compare it with the satellite product. The photic and penetration depths at the Bermuda Atlantic Time Series (BATS) station were obtained from the diff...

The determination of environmental variables spatial-temporal patterns is a necessary matter to understand the relation between environment and bleaching susceptibility. It is equally important the identification of bleaching pattern according its intensity, localization or year of occurrence. Knowing these patterns, is possible to create and test...

The reef ecosystem depends on healthy zooxanthellae, symbiotic microalgae that live in coral tissues. Under stressful conditions, the host corals expel the zooxanthellae in a phenomenon called bleaching. The stress can be inducted by environmental changes and results in severe impacts on coral metabolism, sometimes leading to death. The present stu...

Shallow waters represent potential risks to navigation inside estuaries. Therefore, theymust be well described and data must be always updated. Traditional hydrographic methods have difficult to cover shallow areas due to them extension and low relief. An alternative is the use of satellite images for mapping the areas, with the advantage of low co...

We have performed a temporal analysis of the decrease of mangrove area in the Paranaguá Estuarine Complex (CEP) along 20 years. This has been compared to social-economic indicators of the Paranaguá urban development, which is a city adjacent to CEP. TM/Landsat images and geoprocessing techniques were used to extract and analyze spatial information...

The aim of this work is to evaluate the accuracy of three classification algorithms used to map land use and land cover in the coastal zone of the state of Bahia using TM/Landsat and CCD/CBERS images from 1996 and 2005. The accuracy test made use of the kappa index and statistics parameters. The use of CCD images showed relatively better statistica...

It is possible to analyze phytoplankton absorption features using the continuum removal technique. This work aims to use this technique to identify the more sensible wavelengths in relation to chlorophyll concentration. Field data were collected in 51 points in Ibitinga Reservoir (SP_Brazil), from 24 to 28/October/2005, using FieldSpec Hand Held sp...

Satellite images offers, at low costs, bathymetric maps of areas that are difficult to cover for traditional hydrographic methods. In the north area of the Estuarine Complex of Paranaguá the last bathymetric update was made in the 50’s, and in the inner part of the Guaratuba Bay there are no bathymetric data. A bathymetric mapping of these areas, e...

Before implementation hydrodynamical and ecological models in estuarine systems it is necessary a set of morphological and hydrological information at different spatial scales. The quality of this information will affect directly the model quality. A classification with three hierarchical levels was done for the Paranagua Estuarine Complex focusing...