This study analyzed the seasonal variation of sedimentary reservoirs in sandy beaches located at the insular margin of a tidal inlet (Itamaracá Island, Pernambuco, Brazil). We measured the sedimentary budget and identified the dominant coastal processes (accretion or erosion) from Dec/2017 to Dec/2018. In six field campaigns by a Remotely Piloted Aircraft System, digital terrain models and extracted cross shore profiles were obtained which allowed for the quantification of beach morphology variability by variations in sedimentary volume. The following three sectors were classified and analyzed according to their location and coastal alignment in relation to the tidal inlet: internal (O–L), intermediate (SW–NE), and external (SN) sectors. ERA Interim reanalysis data were used to evaluate the regional standards of ocean surface waves and wind, showing predominance of southeast (109° and 124°, respectively) and wave power with average peaks of 46.5–51.8 kW/m (dry season) and 57–65.3 kW/m (rainy season). Sedimentary gain took place between Apr–Jul/2018, with Sep–Dec/2018 being the period of greatest loss. The internal sector showed positive sedimentary budget (+704.52 m³) with the prevalence of the accretion process, while both intermediate and external sectors lost about 5009 and 14,110 m³, respectively, with the erosive process prevailing at the end of the studied period.

本研究分析了位于潮汐入口（巴西伯南布哥州伊塔马拉卡岛）岛边缘的沙滩中沉积水库的季节性变化。我们测量了沉积收支并确定了 2017 年 12 月至 2018 年 12 月的主要海岸过程（增生或侵蚀）。在远程驾驶飞机系统的六次野外活动中，获得了数字地形模型和提取的跨海岸剖面，从而可以通过沉积体积的变化对海滩形态变化进行量化。根据与潮汐入口相关的位置和海岸线对以下三个扇区进行分类和分析：内部 (O-L)、中间 (SW-NE) 和外部 (S N) 扇区。ERA临时再分析数据用于评估海面波浪和风的区域标准，显示东南（分别为109°和124°）和波功率的优势，平均峰值为46.5-51.8 kW / m（旱季）和57-65.3 kW/m（雨季）。沉积物增加发生在 2018 年 4 月至 7 月之间，其中 2018 年 9 月至 12 月是损失最大的时期。内部部门显示出正的沉积收支（+704.52 m ³），增生过程盛行，而中间部门和外部部门分别损失了约 5009 和 14,110 m ³，在研究期结束时侵蚀过程盛行。