Natural and social conditions of Princesa, a macrotidal sandy beach on the Amazon Coast of Brazil

This study took place at Princesa Beach, located in an area of environmental protection on the Amazon coast of Brazil. The aim was to evaluate the impact of natural processes and human activities on this macrotidal beach, and provide local authorities with guidelines for the implementation of a coastal management program. Data on social and natural variables were collected between November, 2008, and August, 2010. All amenities on the beach were identified and georeferenced using a GPS in August, 2010. Four campaigns of over 25 hours duration were conducted during spring tide periods November, 2008, and March, June, and September, 2009 for the collection of hydrodynamic and hydrologic data. Motorized vehicles are prohibited on the island. The waterfront of Princesa beach is characterized by the presence of a small number of buildings. The beach receives large numbers of visitors only during July and certain bank holidays. The recreational consumption of drugs constitutes the island’s main social problem. Climatic and hydrological conditions were the main factors responsible for the high water turbidity and dissolved oxygen levels, and elevated concentrations of chlorophyll a and dissolved nutrients. The study area was not adversely affected by thermotolerant coliform levels. In order to guarantee the environmental integrity of the beach over a long term, the authors suggest: (i) the construction of an adequate public sanitation system, (ii) creation of garbage recycling programs (to reduce refuse in the dunes), (iii) incentives for the development of ecotourism programs, (iv) regulation of land use, and (v) intervention for the control of recreational drug use.