Next Article in Journal
Hermetia illucens L. Frass in Promoting Soil Fertility in Farming Systems
Previous Article in Journal
An Examination of EIA Frameworks in Laos and China: Distinct Enforcement Strategies and Issues in Public Engagement
Previous Article in Special Issue
Subsidence Monitoring and Driving-Factor Analysis of China’s Coastal Belt Based on SBAS-InSAR
 
 
Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
Journals
Sustainability
Volume 17
Issue 24
10.3390/su172411046
sustainability-logo
Submit to this Journal Review for this Journal Propose a Special Issue
► Article Menu

Article Menu

share Share announcement Help format_quote Cite question_answer Discuss in SciProfiles
first_page
settings
Order Article Reprints
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Article

Managing Coastal Erosion and Exposure in Sandy Beaches of a Tropical Estuarine System

by
Rodolfo J. V. Araújo
1,
Tereza C. M. Araújo
1,
Pedro S. Pereira
2,
Heithor Alexandre de Araujo Queiroz
3,4 and
Rodrigo Mikosz Gonçalves
5,*
1
Department of Oceanography, Federal University of Pernambuco, Arquitetura Ave, Recife 50740-550, PE, Brazil
2
Laboratory of Coastal Oceanography, Federal University of Santa Catarina, Campus Universitário Reitor João David Ferreira Lima, Florianópolis 88040-900, SC, Brazil
3
Federal Institute of Education, Science and Technology of Bahia (IF Baiano), Guanambi Campus, Guanambi 46430-000, BA, Brazil
4
National Institute for Space Research (INPE), Av. dos Astronautas, 1758, São José dos Campos 12227-010, SP, Brazil
5
Nucleus of Technology, Agreste Academic Center, Federal University of Pernambuco, Marielle Franco Ave, Caruaru 55014-900, PE, Brazil
*
Author to whom correspondence should be addressed.
Sustainability 2025, 17(24), 11046; https://doi.org/10.3390/su172411046
Submission received: 25 October 2025 / Revised: 6 December 2025 / Accepted: 8 December 2025 / Published: 10 December 2025
(This article belongs to the Special Issue Applications of Remote Sensing in Sustainable Coastal Resources and the Environment)
Browse Figures
Versions Notes

Abstract

Integrated Coastal Zone Management (ICZM) requires multi-scalar, high-resolution monitoring data to effectively address climate change impacts, particularly sea-level rise and accelerated erosion. This study presents an innovative Remote Sensing (RS) and Geoinformatics approach to precisely quantify and contextualize the exposure of sandy beaches. The research focuses on the highly dynamic insular tidal inlet margin of the Pontal Sul da Ilha de Itamaracá, located within a tropical estuarine system in Northeast Brazil that is subject to intense anthropogenic pressure. The methodology of this study integrates high-resolution GNSS-PPK surveys from two seasonal cycles (2017–2018) with a Difference of DEMs (DoD) analysis to precisely quantify seasonal sediment transport. Furthermore, a multi-temporal analysis leverages the Fort Orange Archaeological Site as a stable datum, combining colonial-era maps with modern satellite imagery to trace shoreline evolution. During the 2017–2018 period, maximum erosion (up to ~2.60 m in altimetric losses) affected the southern and central-northern shoreline, while accretion (up to ~2.25 m in altimetric gains) occurred between these erosional sectors and in the northeastern offshore area. This multi-scalar approach provides the robust data necessary for ICZM, effectively prioritizing sustainable, nature-based strategies that align with local administrative capacities.

1. Introduction

Sandy beaches are fundamental ecosystems, providing essential environmental services to biodiversity, climate regulation, and the livelihood of numerous coastal communities [1,2,3]. These environments serve as a natural buffer against marine hazards and underpin significant economic, recreational, natural, and scenic resources [3,4,5]. However, accelerated human activities, including unsustainable extractive practices and unplanned urban development, are critically overexploiting these areas, severely threatening the sustainability of their ecosystemic services [6,7,8].
Consequently, there is an increasing worldwide emphasis on preserving a healthy coastal environment through safeguarding natural habitats and pollution reduction [9]. The management of coastal zones often faces a critical imbalance, where quick, short-term protective measures are prioritized over long-term sustainable use, particularly in areas subject to high tourism and real estate speculation [10,11].
Effective governance thus necessitates an Integrated Coastal Zone Management (ICZM) approach, which mandates the consideration of natural, ecological, social, and vocational characteristics for truly sustainable development [12,13,14,15]. The challenge is amplified in estuarine systems, which are geologically dynamic and vulnerable to the synergistic impacts of natural processes and anthropogenic actions [16,17]. Historically, the pattern of occupation along the Brazilian shoreline, particularly around estuarine areas, has been characterized by unplanned and resource-intensive urban densification [18,19]. This interference with the natural system exacerbates the risk of coastal erosion [20,21,22,23].
In Brazil, the consolidation of ICZM instruments is lagging, frequently resulting in misguided and expensive interventions that lead to the misallocation of treasury resources [24]. Studies highlight the persistent need for robust scientific information and subsidies to support effective normative instruments, establishing a clear connection between environmental problems and political response [12,14]. Thus, there is a clear need to improve governmental actions and guidelines for coastal management by integrating socioeconomic, environmental aspects, and coastal hazard mitigation [25] for which Remote Sensing (RS) and Geographic Information Systems (GIS) can provide an essential foundation.
RS technologies allow for the essential monitoring of spatial and altimetric variations, critical for managing vulnerable environments subjected to intense real estate speculation [26,27,28,29]. However, effective ICZM relies on high-fidelity 3D data that can resolve short-term seasonal dynamics (erosion/accretion) and link them to long-term historical evolution; such multi-scalar quantitative assessments are often missing.
The Pontal Sul da Ilha de Itamaracá (PSII), on Pernambuco’s north coast, presents an ideal case study. The area, characterized by low natural sediment input [18] and submerged reefs [30], has a deep history of occupation dating back to the colonial period, evidenced by the construction and repeated defensive works around Fort Orange [31,32]. This history illustrates that human use patterns have always interfered with the natural sediment availability [33].
Based on the ICZM guidelines [34], and leveraging modern topo-bathymetric techniques and historical RS data, the specific objectives of this study are: (i) To quantify morphological variation by describing the altimetric variation and the seasonal transport of sediment supply in the study area; (ii) To assess multi-temporal exposure by analyzing the beach environment’s exposure to coastal erosion and evaluating the risk to public, private, historic, and cultural patrimony, using the Fort Orange archaeological site as a long-term record of environmental change; (iii) To propose sustainable strategies compatible with the municipal reality and the natural vocation of the coastal environment.
The novelty of this research lies in its multi-scalar methodological integration, combining high-fidelity 3D altimetric data (GNSS-PPK/DoD) with a unique historical-spatial analysis, to deliver precise, actionable information that moves beyond simple shoreline mapping to address the complexities of coastal vulnerability and support financially and ecologically sustainable ICZM implementation in a tropical estuarine setting.

2. Study Area

The study area is the Pontal Sul da Ilha de Itamaracá (PSII), a coastal environment located on the north shore of Pernambuco state, Northeast Brazil, within the Recife metropolitan region (Figure 1a,b). PSII is the southern extremity of Itamaracá Island, which is separated from the mainland by the 20 km-long Santa Cruz Canal (CSC). The canal connects to the Atlantic Ocean via northern and southern estuaries (Figure 1c). This research specifically focuses on the sandy beaches immediately north of the CSC-South mouth, a high-energy zone critical for sediment transport analysis (Figure 1d).
Our analysis focuses specifically on: (i) the sandy beach strip on the island margin of the east face, immediately north of the CSC-South mouth; (ii) the adjacent dynamic sandbars and extensive low-tide terrace; and (iii) the vicinity of the Fort Orange Archaeological Site (Figure 1d). The physical setting is characterized by a narrow continental platform and discontinuous lines of submerged sandstone reefs to the east, naturally limiting the remobilization and supply of coastal sediments [18,30].
The PSII is situated in the Coastal Lowland, with a Tropical Atlantic climate featuring distinct bimodal seasonality: a dry (summer, October–March) and a rainy (winter, April–September) seasons. This bimodal pattern, driven by prevailing SE winds in winter and weaker NE winds in summer, is the primary control on the morphodynamic variations and seasonal sediment transport of the beaches [27,28,30]. The study area is characterized by prevailing SE oceanic waves, and astronomically driven tides dominated by tidal currents. The substrate includes terrigenous and carbonate sediments, forming sandy features like beaches, spits, and low-tide terraces, within an irregular and complex seabed topography. Anthropogenic development has significantly compounded natural vulnerability. Itamaracá island, a highly sought-after tourist destination, experienced rapid, unplanned urbanization and real estate speculation between 1980 and 1990 [33]. This poorly managed occupation led to the installation of structures on dynamic areas (dunes and post-beach), directly interfering with the natural sediment availability and accelerating the coastal erosion process [11]. The area currently houses the regional headquarters of the Chico Mendes Institute for Biodiversity Conservation/Marine Mammal Center (ICMBio/CMA—Acronym in the Portuguese language) and is a critical tourist hub, both highly exposed to coastal erosion [2,11,27,28].
The Fort Orange archaeological site, initially built by the Dutch (~1631) and later known as the Santa Cruz Fortress after being conquered by Portugal, serves a vital function in this study. Its fixed position as a historical monument, documented since the 17th century, provides a crucial reference point for the multi-temporal analysis. Positional uncertainty in the colonial maps was mitigated by georeferencing them directly to the fixed archaeological features of the Santa Cruz Fortress [31,32,35]. The historical records of repeated repairs and defensive works against the “blows of the sea” demonstrate that the fortress’s southern and southeastern flanks have been historically exposed to the intense hydraulic action and tidal currents of the CSC-South [31]. The exposure of this significant cultural heritage [36] asset directly links the physical coastal dynamics analyzed by Remote Sensing to the long-term sustainability and management requirements of the region’s cultural patrimony.

3. Materials and Methods

3.1. High-Resolution Morphological Monitoring (GNSS-PPK and DoD)

The primary objective of quantifying seasonal sediment transport was achieved through topo-bathymetric surveys conducted via Global Navigation Satellite System—Post-Processed Kinematic (GNSS-PPK). This approach was used to generate Digital Terrain Models (DTMs) for the beach strip (topographic), the low-tide terrace, and the sandbars (bathymetric) located on the east-facing island margin (see, Figure 1d).

3.1.1. GNSS-PPK Survey and Data Acquisition

The geodetic points (3DGNSS) were collected across the entire survey area using transverse profiling, oriented perpendicularly to the beach. The survey employed a pair of GNSS receivers (Figure 2a), configured as follows: (i) a base station (Figure 2b), recording at a 5 s interval, established the reference for post-processing corrections; and (ii) a rover (Figure 2c,d), also recording at a 5 s interval, determined the measurement trajectory [27,37].
Surveys were systematically executed during spring tide periods (low tide, i.e., 0.0–0.2 m) to maximize exposed area coverage (~383,340.1 m2), aligning with tide forecasts (from Directorate of Hydrography and Navigation of the Brazilian Navy) for the Port of Recife (geographically, ~27 km from the study area). Six surveys were conducted across two complete seasonal cycles, covering the beginning and end of the rainy season: April, September, and November 2017 (April 2017, September 2017, November 2017) and April, September, and December 2018 (April 2018, September 2018, December 2018). The morphology of the study area is detailed in [27,28,38].
A comprehensive assessment of horizontal and vertical RMSE values for GNSS techniques in beach surveys has been discussed by [39], who examined the strengths and limitations of relative kinematic (RK), real-time kinematic (RTK), and precise point positioning (PPP) methods. Ref. [40] demonstrated that drone-based (RPAS) photogrammetric accuracy in coastal environments is strongly influenced by factors such as flight time, flight altitude, forward image overlap, and the number of ground control points. In the present study, best practices for relative GNSS surveying were adopted, including the placement of the base station in close proximity to the rover and the distribution of ground control points throughout the study area. Owing to the relatively small size of the survey area, centimeter-level accuracy was attained in both the GNSS measurements and the RPAS-derived products (DTM and orthophoto). Appendix A includes a list that compares existing coastal erosion monitoring methods.

3.1.2. Data Processing and Accuracy Assessment

Data were transformed and referenced to the Brazilian official horizontal Datum SIRGAS 2000 and plane coordinates UTM 25S. To ensure the high data reliability necessary for altimetric change detection, an acceptance criterion was established: measured points were approved only if the horizontal and vertical accuracy was greater than >0.10 m, with a 95% significance level [27]. This criterion defined the measurement precision baseline for the subsequent volumetric analysis.

3.1.3. GIS Processing and Morphological Change Quantification

Using Geographic Information System (GIS) software (QGIS 3.4 Madeira version), the processed 3DGNSS points were interpolated with a Triangulated Irregular Network (TIN) algorithm to produce monthly Digital Terrain Models (DTMs) at a 5 m2/pixel spatial resolution. This approach accurately reproduces terrain discontinuities and complex relief morphology while avoiding the data smoothing and statistical uncertainties (e.g., Kriging).
To ensure maps with the same dimensions, the area boundaries for each DTM were delimited using a single polygonal layer of section. Morphological variations (sediment loss or gain) were quantitatively assessed by comparing the DTMs using the Difference of DEMs (DoD) method. The uniform dimension enabled the computation of the altimetric balance via DoD, where the accuracy criteria were used to define the Minimum Level of Detection (MLD) for Elevation Models change [26,27,29]. Using a minimum detection level of 0.10 m, changes in the topo-bathymetric maps below ±0.10 m were deemed insignificant, while changes exceeding this threshold were considered real. For clarity, the results are visualized using a color scale that highlights changes greater than ±0.20 m.

3.2. Multi-Temporal Coastal and Heritage Assessment

The evaluation of heritage exposure (public, private, historical, and cultural) was based on a comprehensive multi-source analysis that integrated the short-term seasonal morphological variations (Section 3.1) with long-term historical records and modern Remote Sensing imagery. This phase aimed to place the observed erosion dynamics into a comprehensive spatial and temporal context. The datasets used for this multi-temporal assessment included both recent high-resolution RS imagery and deep historical archives.
Modern imagery utilized included: (i) aerial surveys from 1975 and 1989 (SEMAS/PE institutional collection); (ii) a panchromatic orbital image from the Sino-Brazilian mission CEBERS 4 PAN (2018) with a 5 m spatial resolution; and (iii) aerial field record images captured by a quadcopter (UAV) between 2017–2019. These images, in conjunction with the GNSS-derived DTMs, facilitated the analysis of urban evolution, historical shoreline retreat, and the contemporary condition of exposure around the Fort Orange archaeological site.
To trace the long-term evolution of the PSII, a search was conducted for historical documents and images (e.g., photographs, plans, iconographies, and maps) in key databases: the Dutch National Archives and the digital public collection of the Institute of National Historical and Artistic Heritage (IPHAN—Acronym in the Portuguese language). Images published in scientific journals were also used (e.g., [41]). This historical dataset was critical for: (i) documenting the earliest recorded damages to Fort Orange caused by coastal dynamics (e.g., hydraulic action of the CSC-South); (ii) recording the history of past structural interventions; and (iii) using Fort Orange as a stable, fixed reference point for understanding the morphological and urban evolution of the PSII over several centuries. This dataset, complemented by previous studies on sediment dynamics [27,28], anthropogenic impacts on the coastal zone [2,39] and hydrodynamics [30], provided the foundation for the multi-temporal assessment of how coastal dynamics affect the shoreline and historical heritage. Statistical models were not used to quantitatively separate anthropogenic impacts from natural coastal change. Instead, correlation was demonstrated by aligning periods of accelerated erosion with periods of intense urbanization, using historical and seasonal data. This approach relies on multitemporal correlation rather than causal isolation.

3.3. ICZM Strategies and Sustainability Framework

To fulfill the objective of presenting sustainable management strategies, the evaluation of alternatives was grounded in established ICZM principles and legislative frameworks. This framework involved observing concepts from the Guide to Guidelines for the Prevention and Protection of Coastal Erosion [34], supplemented by other ICZM instruments (e.g., [7,42,43,44]). Data from the Brazilian Institute of Geography and Statistics (IBGE—Acronym in the Portuguese language) were integrated to assess the political-administrative and financial capacity of the municipality of Itamaracá Island, providing a realistic context for proposed solutions.
This evaluation served to (i) identify non-structural actions (e.g., spatial planning, retraction) and structural actions (e.g., beach nourishment, hard structures) compatible with the natural dynamics; and (ii) present scientifically based alternatives that integrate coastal protection with sustainable use, moving away from the common practice of generic and punctual solutions often seen on the coast.

4. Results

4.1. High-Resolution Coastal Morphodynamics (GNSS-PPK and DoD)

The topo-bathymetric surveys generated across two full seasonal cycles (2017–2018) captured the variations in the beach strip, intertidal terrace, and sandbars at the PSII’s eastern margin.

4.1.1. Seasonal Altimetric Patterns (Figure 3)

The study area exhibited clear seasonal sedimentary dynamics between April 2017 and December 2018, characterized by distinct elevation changes and morphological reorganization (Table 1): (i) in April 2017, recorded the highest elevation (3.70 m, northern limit) and a low of −1.28 m (northeastern border), with two distinct sandbanks indicating calm summer accumulation; (ii) in September 2017, showed lower elevations (3.10 m and −1.00 m) and energetic winter conditions, forming storm-profile terraces and sandbanks; (iii) in November 2017, maintained moderate elevations (3.00 m and −0.70 m) with sandbank expansion and new eastern sections, showing a seasonal transition lag; (iv) in April 2018, recorded 2.90 m and −1.40 m, with a persistent NE-E depression and near-merged central sandbanks; (v) in September 2018, ranged from 3.00 m to −0.80 m, featuring sandbank separation and landward sediment shift; and (vi) in December 2018, showed elevated levels (3.20 m and −1.00 m) with sandbank-beach connectivity and central terrace linkage, indicating dry-season sediment return. These patterns demonstrate cyclical sediment transport between beach and offshore zones, responding to seasonal meteo-oceanographic forcing.
Table 1. Summary of Seasonal Sedimentary Dynamics (2017–2018).
Table 1. Summary of Seasonal Sedimentary Dynamics (2017–2018).
PeriodRelief Variation (Max/Min)Morphological Changes
April 20173.70 m/−1.28 mFormation of two distinct sandbanks; indicates calm summer accretion.
September 20173.10 m/−1.00 mEnergetic winter conditions; formation of storm-profile terraces and sandbanks (shift from accretion to erosion).
November 20173.00 m/−0.70 mSandbank expansion; new eastern sections formed (indicating a lag in seasonal transition).
April 20182.90 m/−1.40 mPersistent NE-E depression; central sandbanks nearly merged (continued offshore sediment storage).
September 20183.00 m/−0.80 mSandbank separation; formation of a new portion; landward sediment shift (onset of seasonal reversal).
December 20183.20 m/−1.00 mSandbank-beach connectivity; central terrace linkage (active dry-season sediment return to beach).
Sustainability 17 11046 g003
Figure 3. PSII Eastern margin’s sandy features relief survey.
Figure 3. PSII Eastern margin’s sandy features relief survey.
Sustainability 17 11046 g003

4.1.2. Spatiotemporal Sediment Budget (DoD) (Figure 4)

The Difference of DEMs (DoD) method, applied with a minimum level of detection, precisely quantified sediment gains and losses across the study period (Table 2).
Winter Period (April to September 2017 and April to September 2018): these periods exhibited altimetric losses on the beach strip (erosion) and corresponding vertical gains across the low-tide terraces. Between April and September 2017 (April/September 2017), the area exhibited: Vertical losses up to −1.70 m, located parallel to the central-northern shoreline and near the SE bulwark of Forte Orange, following the NE orientation of the main sandbank. Vertical gains up to +1.30 m, distributed along the low-tide terraces and sandbanks. This pattern confirms the expected winter morphology, with sediment moving seaward. Between April and September 2018, the expected pattern continued with: (i) losses of −1.40 m concentrated near the beach face; and (ii) gains of +1.20 m along the sandbanks.
Summer Accretion (November 2017 to April 2018 and September to December 2018): these periods registered losses on the beach face (up to) but significant corresponding gains (up to) concentrated between the beach stretch and the post-beach zone, indicating sediment migration towards the coastline. Between September and November 2017, a persistence of the winter pattern was observed, with vertical gains of up to +0.70 m distributed across the foreshore and shoreface, and losses of up to −1.07 m in a narrow strip parallel to the beach orientation. This indicates a delayed shift to the expected summer morphological regime. Between November 2017 and April 2018, the expected summer pattern emerged, with losses of up to −1.20 m concentrated on the shoreface (notably at the NE boundary) and gains of up to +1.00 m on the foreshore and backshore. This period also featured sandbank movement towards the central beach. The subsequent summer (September to December 2018) showed relatively uniform changes of ±1.15 m across the study area, with the key development being sediment movement that formed a connection between the main sandbank and the beach.
Sustainability 17 11046 g004
Figure 4. Differences between the elevation models: altimetric variations in the surveyed relief and movement of sediment supplies, expressed in terms of gain (blue) and loss (red).
Figure 4. Differences between the elevation models: altimetric variations in the surveyed relief and movement of sediment supplies, expressed in terms of gain (blue) and loss (red).
Sustainability 17 11046 g004
The applied methodology successfully quantified the net elevation change over the entire survey period by comparing the initial (April 2017) and final (December 2018) topo-bathymetric maps: April 2017/December 2018 identifies the primary areas of change. The most significant vertical losses (maximum of −2.60 m) extended from south to north, specifically: (i) adjacent to the shoreline between the SE bulwark of Forte Orange and the ICMBio/CMA headquarters; (ii) associated with the movement of the main sandbank that led to its connection with the beach; and (iii) along a strip parallel to the shoreline, extending in a S-N orientation to the northern limit of the mapped area. Conversely, the main vertical gains (maximum of +2.25 m) were concentrated: (i) adjacent to the ICMBio/CMA beach; (ii) at the new connection between the sandbank and the beach; and (iii) in the area farther offshore on the shoreface, near the NE boundary.

4.2. Multi-Temporal Exposure and Governance Context

The integration of historical archives and modern remote sensing imagery provided a clear socio-ecological context for the observed high-resolution erosion dynamics, demonstrating a history of chronic vulnerability exacerbated by urbanization. Historical records confirm that Fort Orange was originally built on a dynamic barrier island. The long-term multi-temporal analysis (1975–2018), presented in Figure 5, clearly shows urban development intensified between the 1980s and 2000s, transforming the previously uninhabited PSII into a consolidated urban area (Figure 5c–e).
This urbanization, coupled with natural dynamics, resulted in a significant shoreline retreat, particularly evident between 2007 and 2017 (as shown in Figure 6a,b), which led to the narrow beach strip, the expansion of low-tide terraces, and the destruction of infrastructure (e.g., walls, access roads) near the ICMBio/CMA headquarters (Figure 6b).
The Fort Orange archaeological site (Santa Cruz Fortress) serves as a physical record of chronic erosion. Historical documents, such as the 1788 damage plan (Figure 7a), show that the fortress was historically susceptible to the hydraulic action of the CSC-South. Currently, the SW and SE bastions, along with the entire southern curtain, are under the direct action of waves and tidal currents during high tide (see Figure 8b,c).
High-tide imagery confirms the coastline has receded significantly since 2007 (Figure 8d), fully exposing the fortress’s inner wall (Figure 8e) and forcing adjacent public facilities (ICMBio/CMA) and private commerce to build improvised hard structures. The analysis of IPHAN’s documents [45] and historical evidence (Figure 7) confirms that past interventions (and even recent proposals) targeting only small sections of the fort were structurally insufficient to guarantee the safety of the entire fortress, highlighting a persistent disconnect between the scale of coastal dynamics and management solutions.
Data provided by IBGE (up to 2022) indicates that the municipality of Ilha de Itamaracá, had a total revenue of US$20,493,576.00 and committed expenses of US$19,137,000.00 (in 2017), it achieved a per capita GDP of US$2450.00 (in 2019) and had an estimated permanent population of 27,076 inhabitants (in 2021), limiting its capacity to fund coastal defense projects. While the municipality has a structured governance framework via its Integrated Management Plan and Management Committee [44], which aims to balance development with environmental protection as per national guidelines [34], it lacks the financial resources to execute the necessary engineering works for erosion mitigation.
This study classifies sustainable coastal management strategies for the area into two categories, as follows: (i) the first one consists of long-term, cost-effective non-structural actions centered on planning aligned with policy and (ii) the second one involves structural actions, which are physical engineering works typically employed when preventive measures are unsuccessful. However, if implemented without adequate studies and methodologies, these structural actions can result in substantial financial and environmental damage [34,44].
The implementation of non-structural actions in Ilha de Itamaracá is supported by a comprehensive legal framework. This integrates state and federal coastal management laws with municipal instruments, such as an Integrated Management Plan and a nautical zoning decree, forming a robust regulatory foundation in ICZM that is tailored to local conditions [38]. Two other non-structural actions are also identified for the area. The first one is managed retreat, involving the permanent relocation of infrastructure; however, this is typically a last resort after protective measures fail, rather than a preventative strategy. The second one is the ‘do nothing’ approach, which entails non-interference with natural coastal processes. This option is often contentious and is only deemed appropriate when all other structural and non-structural interventions are deemed unviable on economic, environmental, technical, or cost–benefit grounds [34].

5. Discussion

The analysis of the topo-bathymetric time series provided reliable insights into the sediment dynamics crucial for the management of the study area’s coastal environment. The spatiotemporal variation of sedimentary stocks corresponded with seasonal dry and rainy periods, confirming the expected pattern of beach accretion in summer and erosion with the formation of adjacent sandbanks in winter. This study’s findings are strongly supported by previous literature. The seasonal sediment pulse observed here aligns with the accretion and erosion periods documented by [27], who also reported a negative sediment budget for the eastern PSII shore, linking sediment loss to increased wave energy in winter. This corroborates the net erosion (max. −2.60 m) observed between April 2017 and December 2018 in our study, particularly from the central to northern areas. The research context is framed by studies on human impact and coastal governance. Ref. [46] classified the PSII as highly impacted, underscoring the need for integrated management, a concern echoed by [2] in their assessment of Itamaracá Island. Furthermore, the connection between wave climate, morphological patterns, and the resulting management implications, as discussed by [26], in the United Kingdom, and [29], in Australia, validates the importance of the dynamics recorded in this study for informed coastal planning. These findings are corroborated by [28,38], who described multi-temporal deposition and erosion cycles on PSII sandy beaches over a 36-year period (1984–2020), identifying distinct medium and long-term trends. Their work also correlated interannual shoreline variability and wave power with ENSO phase oscillations.
The availability of legal and management instruments emphasizes that the municipal administration has the essential framework for integrated coastal management. However, as observed by [14], the mere existence of these entities (e.g., the PGI Orla Itamaracá, or Integrated Management Plan for the Itamaracá Seafront, and its management committee) does not guarantee efficient ICZM due to practices that disregard legislation, unsustainable development, and a lack of scientific data. The consistent finding of a governance deficit on Itamaracá Island is corroborated by other studies. Ref. [46] classified the region as highly anthropized and called for ICZM. Similarly, Ref. [2] found ICZM to be deficient in the Itamaracá municipality from 2000 to 2010, despite concurrent improvements in socio-economic indicators.
The structural actions observed so far, mostly punctual and rockfills, are inadequate for controlling the erosive process and may even aggravate it [14,19,34]. Beach nourishment is identified as the optimal structural measure, as it mitigates erosion, restores recreational and ecological areas, and is the least intrusive technological solution. However, this approach requires substantial investment for studies, execution, and licensing, as well as a suitable sediment donor site, which can present significant technical and financial challenges. Given that structural actions like nourishment are costly, require ongoing public maintenance, and must serve the broader community, their implementation demands integrated planning involving all relevant stakeholders and government entities [34,38,47]. Furthermore, Ref. [48] emphasizes that beach nourishment requires decadal-scale data to ensure success. The high-fidelity GNSS-PPK data generated in this study is precisely the technical foundation needed to optimize such a project, allowing for the correct dimensioning of beach nourishment [49] to stabilize the beach and absorb wave energy.
The international context for coastal adaptation is shifting towards sustainable and multi-functional defenses, heavily favouring Nature-based Solutions (NbS), such as dune restoration and the management of coastal wetlands, often integrated into hybrid structures for enhanced resilience [50]. However, the escalating threats from climate change, notably sea level rise and increased storm intensity, also place immense pressure on irreplaceable assets. This includes the global coastal cultural heritage, where quantitative risk assessments reveal a substantial and accelerating threat to historical sites, demanding urgent, dedicated adaptation strategies [51]. Established coastal-erosion protection methods, emphasizing both nature-based strategies and emerging bio-engineered approaches. Recent studies highlight that natural ecosystems, such as coral and oyster reefs, mangroves, saltmarshes, seagrasses, and other biogenic structures, function as highly effective natural buffers capable of dissipating wave energy and reducing shoreline vulnerability [52]. These systems not only provide physical protection but also inspire innovative bioinspired solutions for sustainable coastal-defense design.
Additionally, eco-friendly biocementation techniques have shown promising results for stabilizing sandy coasts. Field experiments using microbially induced and enzyme-induced calcium carbonate precipitation demonstrate measurable improvements in erosion resistance, although the effectiveness decreases over time under marine forcing, indicating the need for periodic reinforcement to ensure long-term protection [53].
Due to financial limitations, the municipality of Ilha de Itamaracá must secure partnerships with state and/or federal governments to fund structural coastal management actions. Therefore, the most viable and sustainable path for the PSII involves prioritizing Non-Structural Actions (e.g., spatial planning and planned retreat) that leverage the legal framework and integrate with essential, optimized structural solutions where heritage is at risk [7].
The historical data confirms that the PSII, the archaeological site, and Fort Orange have always been exposed to erosive processes, dating back to the colonial era, as evidenced by oyster shells and recorded repairs [31,32,54,55]. The contemporary data show that this exposure is now critical, with structures like the former berm [31] exposed to CSC-South waters again, highlighting the continuous long-term regression of the coastline. The continuous erosion, coupled with poorly planned modern occupation, reinforces the failure of historical attempts to fix the coastline and the inadequacy of small-scale protection projects [45]. The coastal dynamics require integrated planning [43] that encompasses the entire PSII system, recognizing that the current erosion process is a natural realignment intensified by human actions.
While the high-resolution GNSS and DoD methods employed here represent a marked improvement over prior qualitative assessments, this study has several key limitations. The two-year observational period is too brief to resolve long-term morphological trends or the impacts of extreme meteorological events on the PSII. Moreover, the exclusive focus on the eastern margin precludes a system-wide analysis of the estuarine sediment budget. Thus, despite the capacity of these techniques to resolve fine-scale seasonal dynamics, long-term contextualization remains dependent on incomplete historical datasets. To mitigate these constraints and strengthen the regional interpretation, this work integrates findings from, e.g., [2,27,28,30,46].

6. Conclusions

This study enabled the identification and analysis of sustainable strategies for the use and protection of the coastal environment at Pontal Sul da Ilha de Itamaracá (PSII) while simultaneously documenting the exposure of its historical, cultural, and infrastructural heritage to active coastal processes. The PSII presents a confluence of interrelated challenges (i.e., complex estuarine dynamics, significant anthropogenic pressure, threats to cultural heritage, and constrained municipal capacity) at a single site. The proposed multiscale methodology is designed for generalization and scaling, delivering (i) an actionable framework focused on priority metrics (e.g., littoral drift), (ii) robust governance enhancements, and (iii) high-fidelity data. Translating this approach to other Brazilian coastal systems would generate critical insights, catalyzing a transition from reactive, one-size-fits-all interventions to proactive, evidence-driven Integrated Coastal Zone Management (ICZM).
The application of Digital Terrain Models (DTMs) and a Difference of DEMs (DoD) analysis revealed clear seasonal patterns in sediment distribution. The results demonstrate a dominant erosional trend in the northern and southern sectors (the latter adjacent to Forte Orange), while the central sector showed sediment accumulation, indicating an internal redistribution of sedimentary stocks.
The integrated analysis of historical and modern imagery recorded a significant realignment of the coastline over time, driven by both localized human interventions and natural dynamics. This historical perspective, using the Forte Orange archaeological site as a reference, highlighted the evolution of urban occupation and environmental changes at the PSII.
It was established that the municipality has an adequate legal framework and ICZM (Integrated Coastal Zone Management) instruments for effective coastal management. However, practical implementation faces challenges. Although beach nourishment is morphologically advantageous, its feasibility is limited by high costs and technical and administrative complexity. A definitive solution will require integrated planning that combines different techniques, rather than isolated interventions.
Therefore, sustainable coexistence with coastal erosion at the PSII depends on the effective application of existing public policies, promoting shared governance and social participation in the management of coastal resources.
The results of this study provide a reliable technical basis to support this decision-making process. Our multi-scalar approach bridges the common gap between high-level policies and practical data. It provides spatially explicit quantitative metrics (i.e., altimetric variation rates, location of critical erosion points) that can be directly integrated into the zoning, prioritization, and engineering design phases of existing Brazilian instruments, such as the Municipal Integrated Management Plan, the Coastal Management Project, licensing, and heritage conservation plans. This allows local policymakers to move from reactive and generic interventions to proactive, targeted, and cost-effective management strategies.

Author Contributions

Conceptualization, R.J.V.A., T.C.M.A. and P.S.P.; methodology, R.J.V.A., T.C.M.A. and P.S.P.; validation, R.J.V.A., P.S.P. and R.M.G.; formal analysis, R.J.V.A. and P.S.P.; investigation, R.J.V.A., T.C.M.A., R.M.G. and P.S.P.; resources, T.C.M.A. and P.S.P.; data curation, R.J.V.A.; writing—original draft preparation, R.J.V.A.; writing—review and editing R.J.V.A., R.M.G. and H.A.d.A.Q.; project administration, R.J.V.A., T.C.M.A. and P.S.P. All authors have read and agreed to the published version of the manuscript.

Funding

This research was financed in part by the Coordination for the Improvement of Higher Education Personnel—Brazil (CAPES Foundation—Finance Code 001) through the doctoral scholarship from the Social Demand Program, under process number 88882.379453/2019-01.

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

The data will not be made publicly available; it will be shared only upon private/individual request.

Acknowledgments

This work was made possible thanks to the support by the following partners: Laboratory of Geological Oceanography (Federal University of Pernambuco); and Secretariat of Environment and Sustainability of the Government of Pernambuco. We would like to thank you for the improvement of this manuscript through the constructive and helpful comments from the anonymous reviewers. The authors, P.S.P. and R.M.G., gratefully acknowledge the support of the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) through research productivity fellowships (PQ/C/CNPq/Proc. 311332/2022–6 and PQ/C/CNPq/Proc. 311357/2025–3, respectively). Their continued support is deeply appreciated.

Conflicts of Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Appendix A

  • List: Comparison of Existing Coastal Erosion Monitoring Methods
  • Satellite Remote Sensing (Landsat, Sentinel)
    • Spatial/Temporal Resolution: 10–30 m; 5–16-day revisit.
    • Strengths: Long historical record; regional shoreline trend detection; identifies large-scale anthropogenic pressures.
    • Limitations: Cannot resolve seasonal or short-term changes; lacks vertical accuracy (limited 3D topography for details).
    • Uniqueness of This Study: Integrates historical RS with centimeter-level 3D data, allowing multi-scalar morphological assessment.
  • Aerial Photography (Manned Aircraft)
    • Spatial/Temporal Resolution: <30 cm; infrequent (annual–decadal).
    • Strengths: Valuable historical archives; useful for long-term shoreline evolution.
    • Limitations: Costly, low repeat frequency; generally provides only 2D information.
    • Uniqueness of This Study: Adds 3D elevation models (DTM/Orthophoto) from GNSS + RPAS, enabling volumetric erosion/accretion analysis.
  • UAV/RPAS Photogrammetry
    • Spatial/Temporal Resolution: 3–5 cm; flexible (weekly/monthly).
    • Strengths: High-resolution data; excellent for short-term and seasonal morphodynamics.
    • Limitations: Accuracy affected by lighting, flight altitude, forward overlap, and GCP configuration; sandy beaches pose challenges.
    • Uniqueness of This Study: Applies optimized flight parameters + dense GCP network + GNSS-PPK, ensuring high-fidelity 3D mapping even on visually homogeneous beaches.
  • GNSS Surveys (RTK, PPK, PPP, RK)
    • Spatial/Temporal Resolution: Centimeter-level point accuracy; on-demand acquisition.
    • Strengths: Best method for precise topographic control; critical for validating other datasets.
    • Limitations: Labor-intensive; limited spatial coverage without UAV integration.
    • Uniqueness of This Study: Employs GNSS-PPK best practices, enhancing accuracy of UAV-derived DTMs and enabling robust analysis.
  • Coastal Video Monitoring Systems (e.g., Argus)
    • Spatial/Temporal Resolution: Meter-scale; very high temporal frequency (minutes–hours).
    • Strengths: Superior for shoreline/runup tracking and surf-zone dynamics.
    • Limitations: Only 2D data; requires fixed infrastructure; lacks vertical information.
    • Uniqueness of This Study: Provides full 3D topographic information, allowing true quantification of erosion/accretion volumes.
  • LiDAR (Airborne, Terrestrial, Mobile)
    • Spatial/Temporal Resolution: 1–10 cm; infrequent due to high cost.
    • Strengths: Industry benchmark for coastal topography; highly accurate vertical data.
    • Limitations: Expensive; limited availability for municipalities or small-scale management.
    • Uniqueness of This Study: Achieves LiDAR-comparable accuracy through affordable GNSS + RPAS workflows, providing a realistic tool for ICZM at the municipal scale.

References

  1. Lucrezi, S.; Saayman, M.; Van der Merwe, P. An assessment tool for sandy beaches: A case study for integrating beach description, human dimension, and economic factors to identify priority management issues. Ocean Coast. Manag. 2016, 121, 1–22. [Google Scholar] [CrossRef]
  2. Lima, J.P.; Gonçalves, R.M.; Schmidt, M.A.R. Avaliação da eficácia do gerenciamento costeiro integrado utilizando AHP (Analytic Hierarchy Process) para a Ilha de Itamaracá, Pernambuco, Brasil. Geociências 2017, 36, 743–753. [Google Scholar] [CrossRef]
  3. Silva, R.; Chávez, V.; Bouma, T.J.; Van Tussenbroek, B.I.; Arkema, K.K.; Martínez, M.L.; Oumeraci, H.; Heymans, J.J.; Osorio, A.F.; Mendoza, E.; et al. The Incorporation of Biophysical and Social Components in Coastal Management. Estuaries Coasts 2019, 42, 1695–1708. [Google Scholar] [CrossRef]
  4. Ariza, E.; Jimenez, J.A.; Sarda, R.; Villares, M.; Pinto, J.; Fraguell, R.; Elisabet Roca, E.; Marti, C.; Valdemoro, H.; Ballester, R.; et al. Proposal for an Integral Quality Index for Urban and Urbanized Beaches. Environ. Manag. 2010, 45, 998–1013. [Google Scholar] [CrossRef]
  5. Botero, C.; Pereira, C.; Tosic, M.; Manjarrez, G. Design of an index for monitoring the environmental quality of tourist beaches from a holistic approach. Ocean Coast. Manag. 2015, 108, 65–73. [Google Scholar] [CrossRef]
  6. Constanza, R.; d’Arge, R.; Groot, R.; Stephen Farberk, S.; Grasso, M.; Bruce Hannon, B.; Limburg, K.; Naeem, S.; O’Neill, R.V.; Paruelo, J.; et al. The value of the world’s ecosystem services and natural capital. Nature 1997, 387, 253–260. [Google Scholar] [CrossRef]
  7. Esteves, L.S. Managed Realignment: A Viable Long-Term Coastal Management Strategy? Springer: Berlin/Heidelberg, Germany, 2014; ISBN 978-94-017-9028-4. [Google Scholar]
  8. Martins, A.M. Serviços Ecossistêmicos de Ambientes Costeiros do Litoral de Pernambuco. Ph.D. Thesis, Federal University of Pernambuco, Recife, Brazil, 2020; 123p. [Google Scholar]
  9. Araújo, M.C.B.; Costa, M.F. Environmental Quality Indicators for Recreational Beaches Classification. J. Coast. Res. 2008, 24, 1439–1449. [Google Scholar] [CrossRef]
  10. Pereira, L.C.C.; Jiménez, J.A.; Medeiros, C.; Costa, R.M. The influence of the environmental status of Casa Caiada and Rio Doce beaches (NE-Brazil) on beaches users. Ocean Coast. Manag. 2003, 46, 1011–1030. [Google Scholar] [CrossRef]
  11. Gonçalves, L.R.; Gerhardinger, L.C.; Polette, M.; Turra, A. An Endless Endeavor: The Evolution and Challenges of Multi-Level Coastal Governance in the Global South. Sustainability 2021, 13, 10413. [Google Scholar] [CrossRef]
  12. Casarín, R.S.; Lacouture, M.M.V.; Durón, F.J.R.; Daniela Pedroza Paez, D.P.; Pérez, M.A.O.; Baldwin, E.G.M.; Calzadilla, M.A.D.; Del Carmen Escudero Castillo, M.; Angélica Félix Delgado, A.F.; Salinas, A.C. Caracterización de la zona costera y planeamiento de elementos técnicos para la elaboración de criterios de regulación y manejo sustentable; Instituto de Ingeniería—UNAM: Mexico City, Mexico, 2014; 117p, ISBN 978-607-02-6287-6. [Google Scholar]
  13. Nel, R.; Campbell, E.E.; Harris, L.; Hauser, L.; Schoeman, D.S.; McLachlan, A.; Preez, D.R.; Bezuidenhout, K.; Schlacher, T.A. The status of sandy beach science: Past trends, progress, and possible futures. Estuar. Coast. Shelf Sci. 2014, 150, 1–10. [Google Scholar] [CrossRef]
  14. Kosyan, R.D.; Velikova, V.N. Coastal zone e Terra (and aqua) incognita e Integrated Coastal Zone Management in the Black Sea. Estuar. Coast. Shelf Sci. 2015, 169, 1–16. [Google Scholar] [CrossRef]
  15. Nicolodi, J.; Gruber, N. Abordagem geográfica da Gestão Costeira Integrada. In Geografia Marinha: Oceanos e Costas na Perspectiva de Geógrafos; Muehe, D., Lins-de-Barros, F.M., Pinheiro, L., Eds.; PGGM: Rio de Janeiro, Brazil, 2020; pp. 382–401. ISBN 978-65-992571-0-0. [Google Scholar]
  16. Lisboa, P.V.; Fernandes, E.H. Anthropogenic influence on the sedimentary dynamics of a sand spit bar, Patos Lagoon Estuary, RS, Brazil. J. Integr. Coast. Zone Manag. 2015, 15, 35–46. [Google Scholar] [CrossRef]
  17. Mitchell, S.B.; Jennerjahn, T.C.; Vizzini, S.; Zhang, W. Changes to processes in estuaries and coastal waters due to intense multiple pressures—An introduction and synthesis. Estuar. Coast. Shelf Sci. 2015, 156, 1–6. [Google Scholar] [CrossRef]
  18. Araújo, M.C.B.; Souza, S.T.; Chagas, A.O.; Barbosa, S.C.T.; Costa, M.F. Análise da Ocupação Urbana das Praias de Pernambuco, Brasil. J. Integr. Coast. Zone Manag. 2007, 7, 97–104. [Google Scholar] [CrossRef]
  19. Souza, C.R.G. A Erosão Costeira e os Desafios da Gestão Costeira no Brasil. Rev. Da Gestão Costeira Integr. 2009, 9, 17–37. [Google Scholar] [CrossRef]
  20. Dallas, K.L.; Barnard, P.L. Anthropogenic influences on shoreline and nearshore evolution in the San Francisco Bay coastal system. Estuar. Coast. Shelf Sci. 2011, 92, 194–204. [Google Scholar] [CrossRef]
  21. Aiello, A.; Canora, F.; Pasquariello, G.; Spilotro, G. Shoreline variations and coastal dynamics: A space-time data analysis of the Jonian litoral, Italy. Estuar. Coast. Shelf Sci. 2013, 129, 124–135. [Google Scholar] [CrossRef]
  22. Davis, A.; Fitzgerald, D.M. Beaches and Coasts, 1st ed.; Blackwell Publishing: Malden, MA, USA, 2004; 419p, ISBN 10 0632043083. [Google Scholar]
  23. Mallmann, D.L.; Pereira, P.S. Coastal erosion at Maria Farinha beach, Pernambuco, Brazil: Possible causes and alternatives for shoreline protection. J. Coast. Res. 2014, 71, 24–29. [Google Scholar] [CrossRef]
  24. Nicolodi, J.L.; Asmus, M.L.; Polette, M.; Turra, A.; Seifert, C.A., Jr.; Stori, F.T.; Shinoda, D.C.; Mazzer, A.; Souza, V.A.; Gonçalves, R.K. Critical gaps in the implementation of Coastal Ecological and Economic Zoning persist after 30 years of the Brazilian coastal management policy. Mar. Policy 2021, 128, 104470. [Google Scholar] [CrossRef]
  25. Wang, Y.; Imai, K.; Horikawa, H. Tsunami Early Warning Using High-Frequency Ocean Radar System in the Kii Channel, Japan. Seismol. Res. Lett. 2024, 96, 990–1000. [Google Scholar] [CrossRef]
  26. Wiggins, M.; Scott, T.; Masselink, G.; Russell, P.; McCarroll, R.J. Coastal embayment rotation: Response to extreme events and climate control, using full embayment surveys. Geomorphology 2019, 327, 385–403. [Google Scholar] [CrossRef]
  27. Araújo, R.J.V.; Pereira, P.S.; Lino, A.P.; Araújo, T.C.M.; Gonçalves, R.M. Morphodynamic Study of Sandy Beaches in a Tropical Tidal Inlet Using RPAS. Mar. Geol. 2021, 438, 106540. [Google Scholar] [CrossRef]
  28. Araújo, R.J.V.; Araújo, T.C.M.; Veleda, D.; Pereira, P.S.; Lino, A.P.; Gonçalves, R.M. Shoreline, wave power and global teleconnection influences on a South Atlantic tropical island (Tamarack Island, 1984 to 2020). Catena 2025, 250, 108762. [Google Scholar] [CrossRef]
  29. Silva, A.P.; Silva, G.V.; Strauss, D.; Murray, T.; Woortmann, L.G.; Taber, J.; Cartwright, N.; Tomlinson, R. Headland bypassing timescales: Processes and driving forces. Sci. Total Environ. 2021, 793, 148591. [Google Scholar] [CrossRef] [PubMed]
  30. Medeiros, C.; Kjerfve, B. Hydrology of a Tropical Estuarine System: Itamaracá, Brasil. Estuar. Coast. Shelf Sci. 1993, 36, 495–515. [Google Scholar] [CrossRef]
  31. Barthel, S.G.A. Arqueologia de uma Fortificação: O Forte Orange e a Fortaleza de Santa Cruz em Itamaracá, Pernambuco. Master’s Thesis, Center for Philosophy and Human Sciences, Federal University of Pernambuco, Recife, Brazil, 2007; 168p. [Google Scholar]
  32. Oliveira, A.L.N.; Santos, J.L. A Ilha de Itamaracá e a organização da defesa no período colonial (séculos XVI e XVII): Contribuição para a história do litoral norte de Pernambuco, Brasil. Cad. Do LEPAARO 2014, XI, 21. [Google Scholar] [CrossRef]
  33. Martins, K.A.; Pereira, P.S.; Lino, A.P.; Gonçalves, R.M. Determinação da erosão costeira no Estado de Pernambuco através de geoindicadores. Rev. Bras. De Geomorfol. 2016, 17, 3. [Google Scholar] [CrossRef]
  34. Brasil Grupo de Integração do Gerenciamento Costeiro. GI-GERCO/CIRM Guia de Diretrizes de Prevenção e Proteção à Erosão Costeira; GI-GERCO/CIRM: Brasília, Brazil, 2018; 111p, ISBN 978-85-68813-13-3. [Google Scholar]
  35. Albuquerque, M.; Lucena, V.; Walmsley, D. Fortes de Pernambuco: Imagens do Passado e do Presente; Graftorres: Recife, Brazil, 1999; 204р. [Google Scholar]
  36. Vousdoukas, M.; Clarke, J.; Ranasinghe, R.; Bescoby, D.; Vafeidis, A.; Mentaschi, L.; Feyen, F.; Sabour, S.; Khalaf, N.; Duong, T.; et al. Climate change threatens coastal heritage worldwide. Res. Sq. 2025. [Google Scholar] [CrossRef]
  37. Holanda, T.F.; Gonçalves, R.M.; Lino, A.P.; Pereira, P.S.; Sousa, P.H.G.O. Morphodynamic classification, variations and coastal processes of Paiva beache, PE, Brazil. Rev. Bras. De Geomorfol. 2020, 21, 235–251. [Google Scholar] [CrossRef]
  38. Araújo, R.J.V. Dinámica Costeira e Processos Erosivos: Alternativas de Controle Para o Pontal sul da Ilha de Itamaracá PE, Brasil. Ph.D. Thesis, Federal University of Pernambuco, Recife, Brazil, 2022; 147p. [Google Scholar]
  39. Gonçalves, R.M.; Awange, J.L. Three Most Widely Used GNSS-Based Shoreline Monitoring Methods to Support Integrated Coastal Zone Management Policies. J. Surv. Eng. 2017, 143, 05017003. [Google Scholar] [CrossRef]
  40. Contreras-de-Villar, F.; García, F.J.; Muñoz-Perez, J.J.; Contreras-de-Villar, A.; Ruiz-Ortiz, V.; Lopez, P.; Garcia-López, S.; Jigena, B. Beach Leveling Using a Remotely Piloted Aircraft System (RPAS): Problems and Solutions. J. Mar. Sci. Eng. 2021, 9, 19. [Google Scholar] [CrossRef]
  41. Albuquerque, M. Arqueologia do Forte Orange. Rev. Da Cult. 2009, 15, 37–47. [Google Scholar]
  42. Ministério do Meio Ambiente—M.M.A. Macrodiagnóstico da Zona Costeira e Marinha do Brasil; MMA: Brasília, Brazil, 2008; 242p, ISBN 978-85-7738-112-8. [Google Scholar]
  43. Mangor, K.; Drønen, N.K.; Kærgaard, K.H.; Kristensen, S.E. Shoreline Management Guidelines; DHI: Hørsholm, Denamrk, 2017; 462p, ISBN 978-87-90634-04-9. [Google Scholar]
  44. Ministério da Economia—M.E. Manual Projeto Orla; Secretaria de Coordenação e Governança do Patrimônio da União: Brasília, Brazil, 2022; 324p, ISBN 978-65-997520-0-1. [Google Scholar]
  45. Instituto do Patrimônio Histórico e Artístico, Nacional—IPHAN. Projeto de Recuperação e Revitalização, Formulação de um Modelo de Uso e Gestão e Preparação de um Plano de Financiamento Para o Forte Orange: Sub-Projeto de Contenção do Mar e Projeto Executivo; IPHAN: Recife, Brazil, 2009; 84p. [Google Scholar]
  46. Gonçalves, R.M.; Saleem, A.; Queiroz, H.A.A.; Awange, J.L. A fuzzy model integrating shoreline changes, NDVI and settlement influences for coastal zone human impact classification. Appl. Geogr. 2019, 113, 102093. [Google Scholar] [CrossRef]
  47. Instituto de Tecnologia de Pernambuco—ITEP. Relatório de Impacto Ambiental—RIMA: Recuperação da Orla Maritima Municípios de Jaboatão dos Guararapes, Recife, Olinda e Paulista (Pernambuco); ITEP: Recife, Brazil, 2012; 98p. [Google Scholar]
  48. Luijendijk, A.P.; Schipper, M.A.; Ranasinghe, R. Morphodynamic Acceleration Techniques for Multi-Timescale Predictions of Complex Sandy Interventions. J. Mar. Sci. Eng. 2019, 7, 78. [Google Scholar] [CrossRef]
  49. Alfredini, P.; Arasaki, E. Obras e Gestão de Portos e Costas: A Técnica Aliada ao Enfoque Logístico e Ambiental, 2nd ed.; Blucher: São Paulo, Brazil, 2009; 804p. [Google Scholar]
  50. Worldbankgroup. Global Economic Prospects, January 2022; World Bank Publications: Washington, DC, USA, 2022. [Google Scholar]
  51. Vousdoukas, M.L.; Clarke, J.; Ranasinghe, R.; Reimann, L.; Khalaf, N.; Duong, T.M.; Ouweneel, B.; Sabour, S.; Iles, C.E.; Trisos, C.H.; et al. African heritage sites threatened as sea-level rise accelerates. Nat. Clim. Change 2022, 12, 256–262. [Google Scholar] [CrossRef]
  52. Perricone, V.; Mutalipassi, M.; Mele, A.; Buono, M.; Vicinanza, D.; Contestabile, P. Nature-Based and Bioinspired Solutions for Coastal Protection: An Overview among Key Ecosystems and a Promising Pathway for New Functional and Sustainable Designs. ICES J. Mar. Sci. 2023, 80, 1218–1239. [Google Scholar] [CrossRef]
  53. Li, Y.; Guo, Z.; Wang, L.; Zhu, Y.; Rui, S. Field implementation to resist coastal erosion of sandy slope by eco-friendly methods. Coast. Eng. 2024, 189, 104489. [Google Scholar] [CrossRef]
  54. Albuquerque, M. Arqueologia do forte Orange: O forte holandês. Rev. Da Cult. 2010, 17, 36–43. [Google Scholar]
  55. Albuquerque, M. Arqueologia do Forte Orange II. Rev. Da Cult. 2010, 16, 44–51. [Google Scholar]
Sustainability 17 11046 g001
Figure 1. Location of the study area: (a) Pernambuco, NE–Brazil; (b) North coast of Pernambuco; (c) Itamaracá Island, Santa Cruz canal and submerged reef line; and (d) Southern Point of Itamaracá Island and sandy features mapped area.
Figure 1. Location of the study area: (a) Pernambuco, NE–Brazil; (b) North coast of Pernambuco; (c) Itamaracá Island, Santa Cruz canal and submerged reef line; and (d) Southern Point of Itamaracá Island and sandy features mapped area.
Sustainability 17 11046 g001
Sustainability 17 11046 g002
Figure 2. Trimble® R4 GNSS system: (a) GNSS receivers and controller; (b) rover receiver attached to the backpack-holder; (c) Base station receiver; and (d) Rover walking.
Figure 2. Trimble® R4 GNSS system: (a) GNSS receivers and controller; (b) rover receiver attached to the backpack-holder; (c) Base station receiver; and (d) Rover walking.
Sustainability 17 11046 g002
Sustainability 17 11046 g005
Figure 5. Morphological and urban evolution of the study area: (a) Map of the Dutch period of the PSII; (b) Dutch fort (in pink) circumscribed by the Luso-Brazilian fortress (black lines); (c–e) Pontal Sul da Ilha de Itamaracá.
Figure 5. Morphological and urban evolution of the study area: (a) Map of the Dutch period of the PSII; (b) Dutch fort (in pink) circumscribed by the Luso-Brazilian fortress (black lines); (c–e) Pontal Sul da Ilha de Itamaracá.
Sustainability 17 11046 g005
Sustainability 17 11046 g006
Figure 6. Aerial view of the retreat of the coastline on the east bank, near ICMBio/CMA (at low tide): (a) Beach strip and coastline in 2007; and (b) Receding coastline and low-tide terrace adjacent to sandbars in 2017. The colored markers point to the corresponding areas. Photograph year: lower right corner.
Figure 6. Aerial view of the retreat of the coastline on the east bank, near ICMBio/CMA (at low tide): (a) Beach strip and coastline in 2007; and (b) Receding coastline and low-tide terrace adjacent to sandbars in 2017. The colored markers point to the corresponding areas. Photograph year: lower right corner.
Sustainability 17 11046 g006
Sustainability 17 11046 g007
Figure 7. Damage to the structure of the Fortress of Santa Cruz: (a) Damage plan of 1788; (b–d) Ruins of the SW bastion and the south curtain (1920s, 1950s and 1970s, respectively); (e) Restoration of the SW bastion and the south coastal building curtain.
Figure 7. Damage to the structure of the Fortress of Santa Cruz: (a) Damage plan of 1788; (b–d) Ruins of the SW bastion and the south curtain (1920s, 1950s and 1970s, respectively); (e) Restoration of the SW bastion and the south coastal building curtain.
Sustainability 17 11046 g007
Sustainability 17 11046 g008
Figure 8. Santa Cruz Fortress (high tide): (a) Mangrove area, to the north, and CSC-South, to the south; (b) SE Bastion and South Curtain; (c) SW Bastion and beach huts; (d) The beach of the commercial and tourist center and Fort Orange; and (e) Retreat of the coastline to the west of the fortress. (e) Note the coastline retreat west of the fortress compared to its position. Photograph year: lower right corner. Red square: the same area in different years and perspectives.
Figure 8. Santa Cruz Fortress (high tide): (a) Mangrove area, to the north, and CSC-South, to the south; (b) SE Bastion and South Curtain; (c) SW Bastion and beach huts; (d) The beach of the commercial and tourist center and Fort Orange; and (e) Retreat of the coastline to the west of the fortress. (e) Note the coastline retreat west of the fortress compared to its position. Photograph year: lower right corner. Red square: the same area in different years and perspectives.
Sustainability 17 11046 g008
Table 2. Summary of Sediment Elevation Changes (2017–2018).
Table 2. Summary of Sediment Elevation Changes (2017–2018).
PeriodType of ChangeLocationsElevation Change
Winter Erosion
April–September 2017LossesCentral-northern shoreline; near SE bulwark of Forte Orange.−1.70 m
GainsLow-tide terraces and sandbanks.+1.30 m
April–September 2018LossesNear the beach face−1.40 m
GainsAlong the sandbanks+1.20 m
Summer Accretion
September–November 2017LossesNarrow strip parallel to beach−1.07 m
GainsForeshore and shoreface+0.70 m
November 2017–April 2018LossesShoreface (notably NE boundary)−1.20 m
GainsForeshore and backshore+1.00 m
September–December 2018Net ChangeAcross the study area (uniform)±1.15 m
Net Change (Full Period)
April 2017–December 2018LossesShoreline (Forte Orange to ICMBio/CMA); S-N strip to northern limit−2.60 m (max)
GainsICMBio/CMA beach; sandbank-beach connection; offshore shoreface (NE boundary)+2.25 m (max)
Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content.

Share and Cite

MDPI and ACS Style

Araújo, R.J.V.; Araújo, T.C.M.; Pereira, P.S.; Queiroz, H.A.d.A.; Gonçalves, R.M. Managing Coastal Erosion and Exposure in Sandy Beaches of a Tropical Estuarine System. Sustainability 2025, 17, 11046. https://doi.org/10.3390/su172411046

AMA Style

Araújo RJV, Araújo TCM, Pereira PS, Queiroz HAdA, Gonçalves RM. Managing Coastal Erosion and Exposure in Sandy Beaches of a Tropical Estuarine System. Sustainability. 2025; 17(24):11046. https://doi.org/10.3390/su172411046

Chicago/Turabian Style

Araújo, Rodolfo J. V., Tereza C. M. Araújo, Pedro S. Pereira, Heithor Alexandre de Araujo Queiroz, and Rodrigo Mikosz Gonçalves. 2025. "Managing Coastal Erosion and Exposure in Sandy Beaches of a Tropical Estuarine System" Sustainability 17, no. 24: 11046. https://doi.org/10.3390/su172411046

APA Style

Araújo, R. J. V., Araújo, T. C. M., Pereira, P. S., Queiroz, H. A. d. A., & Gonçalves, R. M. (2025). Managing Coastal Erosion and Exposure in Sandy Beaches of a Tropical Estuarine System. Sustainability, 17(24), 11046. https://doi.org/10.3390/su172411046

Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details here.

Article Metrics

Back to TopTop