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11 th International Symposium for GIS and Computer Cartography for Coastal Zones Management2000 with an extension of boardwalk northward, pluvial drainage system and kiosks installation. Accordingly, imageanalysis included the period of 1986 to 2012 with the aim to consider an earlier period and another one afterseaside urbanization.Table 1. Summary of sedimentary balance (erosion/accretion) per beach zone classified according to erosion damage to seasideinfrastructure (kiosks, pluvial drainage system, boardwalk, pavements, etc.) for periods from 1973 to 2012 and 1986 to 2012.Years1986-20121973-2012Erosion DamageZoneModerate - Zone I Very Strong Strong(Area m²) (Area m²) (Area m²)Accretion 1,005.88 370.63 0.00 0.00Moderate - Zone II(Area m²)Erosion 16,284.32 16,114.92 7,723.83 18,286.76Accretion 0.53 496.03 1,080.80 5,010.78Erosion 39,069.10 31,505.63 6,843.10 13,323.70From 1976 to 2012 there was a negative sedimentary balance for all beach segments. Beach segment on sea cliffsand Morro do Careca base (Zone I), on southern part of study area, suffered intense erosion (about 39,000 m 2 ) andshoreline retreat up to 59 m and of 57 m on northern portion of Ponta Negra Beach (Zone II) during this period, anaverage retreat rate of around 1, 3 m/year. These moderate damage zones experienced high shoreline retraction from1973 to 1986, and even if followed by a constructive phase or a period of stability both faced high erosion rate untilpresent time.Erosion rate, so shoreline retreat, was very intense (around 5,762.2 m 2 ) on segment classified as Strong damagezone. However, this zone on central portion of the beach is facing strong erosion since early 90s with conspicuousfacilities destructions mainly during episodes of high tide, what means that the process of shoreline retraction to thissegment is currently active.Considering beach zone classified according as Very Strong damage area it is noticeable a highly destructivephase conducting to erosion rate of about 31,000 m 2 for the entire period. This is the main urban segment of PontaNegra Beach and crucial to tourism and service sector of economy where seaside facilities has been destroyed continuouslyby erosion driving forces.Shoreline retreat since years 2000 is also confirmed by intermittent beach monitoring but also by evident erosionof beach profile and destruction of seaside infrastructure. During the past few years the destruction of urban facilitiesduring episodes of high water became chronic. Therefore it is obvious that Ponta Negra Beach erosion was anatural process but presently (since 90s) it is getting worse with urban plans that allowed building of seaside infrastructurenear the sea that causes disruption of regular beach and dune sediment exchange. But it is also noticeableon early 90s that the main urbanized portion of Ponta Negra Beach was already under an intense negative sedimentbudget, started previously (70s and 80s).So, sedimentary balance analysis on Ponta Negra Beach indicates that erosion/accretion process apparently occuraccompanying sediment transport dynamics lead by littoral drift and tidal currents. Therefore, erosion amount outweighthe gains occurred in earlier period to entire beach. Nowadays, Ponta Negra Beach north sector is facing intenseerosion on the remaining frontal dunes. All sectors stand out sediment removal from the beach face due tonatural driving forces (waves, currents and tides), but also as a result of runoff from the drainage systems and as aresult of predatory anthropogenic action on beach landforms (such as foreshore and frontal dunes), whose primaryfunction is to protect the coastline.ConclusionThe results of comparative analysis to shoreline changes based on multisource and multiple resolution remotesensing images showed remarkable erosion widespread along all segments of Ponta Negra Beach and adjacent urbanarea with an increase in erosion rates in recent years.Comparison of long-term and short-term period remarkably revealed that erosive is so well marked on both balanceand involves almost 100% of the shoreline increasing since early 90s due to urban sprawl that occupied theadjacent dune and backshore, and also allowed the building of infrastructure closer to shoreline. During years 2000shuman facilities improvement intensified progressive soil impermeabilization and accelerated erosion of beach face.Results undoubtedly indicated strongly erosive character in Ponta Negra Beach in recent years.13