Satellite image mosaic of the Terra Nova Bay area (Victoria Land, Antarctica)

This work has been carried out as part of "Programma Nazionale di Ricerche in Antartide" and was supported financially be ENEA through a joint reasearch-program on Antarctic Earth Science with the University of Siena (Italy). The geopmorphological and glaciological research, of which this work forms a part, is coordinated by Prof. Giuseppe Grombelli.

Habitat map of Danajon Bank, Philippines, derived from a high-spatial-resolution multi-spectral satellite image and georeferenced point intercept transect and spot-check survey field data, using an object-based image classification method

A mosaic of two WorldView-2 high resolution multispectral images (Acquisition dates: October 2010 and April 2012), in conjunction with field survey data, was used to create a habitat map of the Danajon Bank, Philippines (10°15'0'' N, 124°08'0'' E) using an object-based approach. To create the habitat map, we conducted benthic cover (seafloor) field surveys using two methods. Firstly, we undertook georeferenced point intercept transects (English et al., 1997). For ten sites we recorded habitat cover types at 1 m intervals on 10 m long transects (n= 2,070 points). Second, we conducted geo-referenced spot check surveys, by placing a viewing bucket in the water to estimate the percent cover benthic cover types (n = 2,357 points). Survey locations were chosen to cover a diverse and representative subset of habitats found in the Danajon Bank. The combination of methods was a compromise between the higher accuracy of point intercept transects and the larger sample area achievable through spot check surveys (Roelfsema and Phinn, 2008, doi:10.1117/12.804806). Object-based image analysis, using the field data as calibration data, was used to classify the image mosaic at each of the reef, geomorphic and benthic community levels. The benthic community level segregated the image into a total of 17 pure and mixed benthic classes.

Planktic foraminifera analyses of surface sediments and satellite data in the Canary Islands region

The Canary Islands region occupies a key position with respect to biogeochemical cycles, with the zonal transition from oligotrophic to nutrient-rich waters and the contribution of Saharan dust to the particle flux. We present the distribution of geochemical proxies (TOC, carbonate, d15N, d13Corg, C/N-ratio) and micropaleontological parameters (diatoms, dinoflagellates, foraminifera, pteropods), in 80 surface-sediment samples in order to characterise the influence of coastally upwelled water on the domain of the subtropical gyre. Results of the surface-sediment analyses confirmed the high biomass gradient from the coast to the open ocean inferred from satellite data of surface chlorophyll or SST. The distribution of total dinoflagellate cysts, the planktic foraminifera species Globigerina bulloides, the diatom resting spore Chaetoceros spp., and TOC concentration coincided well with the areas of strong filament production off Cape Ghir and Cape Yubi. The warm-water planktic foraminifera Globigerinoides ruber (white), the diatom Nitzschia spp., and the d15N-values showed the opposite trend with high values in the open ocean. Factor analyses on the planktic foraminifera species distribution indicated three major assemblages in the Canary Islands region that represent the present surface-water conditions from the upwelling influenced region via a mixing area towards the subtropical gyre.