Biogeomorphological processes in an arid transgressive dunefield as indicators of human impact by urbanization.

Urban and tourist developments can have long-lasting impacts on coastal environments and fundamentally alter the evolution of coastal dune systems. This is the case of the Maspalomas dunefield (Gran Canaria, Canary Islands), hosting one of the largest tourist resorts in Spain. The resort was built on top of a sedimentary terrace at 25 m above sea level (El Inglés) in the 1960s, and has subsequently affected local winds and therefore aeolian sediment transport patterns. Buildings on the terrace deflect the winds to the south of the dunefield, where the rate of sediment transport accelerated. A shadow zone appeared to the lee side of the resort with a consequent decrease in wind speed and aeolian sediment transport and an increase in vegetation cover. In this paper, first we characterize the environmental changes around El Inglés terrace in recent decades, and describe the changes in the shadow zone through an analysis of the evolution of sedimentary volumes and vegetation characteristics (density, spatial patterns, and plants communities). A series of historical aerial photographs, recent orthophotos and digital elevation models obtained by digital photogrammetry and LiDAR, as well as fieldwork were used to characterize plant communities and spatial-temporal changes in erosive landforms. Results show changes in the pattern and migration rates of dunes located at the southern edge of the urbanization, as well as the formation of blowouts and large deflation areas, where the vegetation increases in density and number of plant communities. We discuss eco-anthropogenic factors that have produced these environmental changes.

Medium and large sized mammal assemblages in coastal dunes and adjacent marshes in southern Rio Grande do Sul State, Brazil / Assembleias de mamíferos de médio e grande porte em dunas costeiras e brejos adjacentes na região Sul do Estado do Rio Grande do Sul, Brasil

This paper presents data on species composition and use of habitat of medium and large sized mammal assemblages in a coastal dunes segment and adjacent marshes at Rio Grande municipality, southern Rio Grande do Sul State, Brazil. Records were obtained through visualization of living animals and identification of footprints, feces and remains. From November 2007 to September 2008, nine 600 m long and 5 m wide linear transects were settled on coastal dunes segment (frontal and intermediate dunes) and adjacent marshes, parallel to ocean shore on a 23 km section at Cassino Beach. Transects were settled in areas under high, medium and low levels of anthropic occupancy (A1, A2 and A3, respectively), being three transects on each area. Fourteen species were recorded, distributed in five orders and 10 families. Lepus europaeus was the most frequent species (81.9% of the transect walks), present in all areas and seasons, followed by Lycalopex gimnocercus (23.5%) and Conepatus chinga (10.3%). Five species were present on A1, seven on A2 and fourteen on A3. Seven species were recorded on frontal dunes, nine on intermediate dunes and 13 on adjacent marshes.

O presente estudo apresenta dados sobre a composição de espécies e uso do hábitat de assembleias de mamíferos de médio e grande porte em um trecho no cordão de dunas costeiras e brejos adjacentes no município de Rio Grande, região Sul da Planície Costeira do Rio Grande do Sul, Brasil. Os registros foram obtidos no período de novembro de 2007 a setembro de 2008 por meio da observação direta de indivíduos e carcaças e da identificação de vestígios (pegadas e fezes). Nove transectos lineares de 600 m de extensão e 5 m de largura, paralelos à praia oceânica, foram estabelecidos sobre um trecho de 23 km do cordão de dunas costeiras e brejos adjacentes no Balneário Cassino. Foram amostradas áreas sob alto, médio e baixo grau de antropização (A1, A2 e A3, respectivamente), sendo estabelecidos três transectos em cada área. Os métodos empregados possibilitaram o registro de 14 espécies sendo Lepus europaeus a mais frequente (81,9% do total de transecções) e presente em todas as áreas e em todas as estações, seguida de Lycalopex gymnocercus (23,52%) e Conepatus chinga (10,29%). Cinco espécies foram registradas em A1, sete em A2 e 14 em A3. Sete espécies foram encontradas nas dunas frontais, nove nas dunas intermediárias e 13 nos brejos adjacentes.