Linear Regression Rate Research Articles

Shoreline Change Analysis in New Washington, Aklan using Digital Shoreline Analysis System (DSAS)

Abstract. Shoreline changes are a critical indicator of coastal vulnerability, impacted by natural processes and human-induced factors such as climate change. This study investigates shoreline changes in New Washington, Aklan, Philippines, focusing on erosion and accretion patterns since 1985. With the use of satellite imagery, coupled with Remote Sensing and Geographical Information System (GIS) techniques, this study examines the spatio-temporal variability in erosion and accretion patterns. Through the Digital Shoreline Analysis System (DSAS), a quantitative analysis of shoreline change rates was conducted. Using four (4) DSAS change metrics such as Endpoint rate (EPR), Linear Regression Rate (LRR), Shoreline Change Envelope (SCE), and Net Movement Shoreline (NMS), it was identified that the shoreline change in Bakhawan Park area is due to its location being at the mouth of Aklan River. Most of New Washington’s shoreline experiences erosion with 0-1.46 m/yr from LRR, eroding at most 40m of sediments in thirty years; evident along areas of Brgy. Tambac and Poblacion. The largest shoreline deviation can be observed in the areas located near the mouth of Batan Bay with 153 meters since 1985.

Dynamics of Shoreline Changes Along the Coast of Subarnarekha and Budhabalanga River Estuary, North Eastern Coast of India Using DSAS Technique: A Geospatial Technology Approach

ABSTRACTThe coastal regions represent one of the most significant environmental and economic resources, offering critical ecosystems that support biodiversity. Shoreline change analysis offers critical insights into coastal dynamics, providing trends in erosion and accretion, enabling effective coastal management and hazard mitigation. In the current study, shoreline change is assessed utilizing the Digital Shoreline Analysis System (DSAS) model for Subarnarekha and Budhabalanga river estuaries in Baleswar district, Odisha, India. The shoreline was extracted using multitemporal satellite images like Landsat‐5 and Landsat‐7 for the years 1991, 2000, and 2011. Similarly Sentinel‐2 and Landsat‐8 satellite imagery were used for the year 2022. The satellite data from 1991 to 2022 were processed using Envi, ArcGIS softwares and the shoreline is extracted for each year using band ratioing methods to demarcate shoreline. In the current research, the net accretion and erosion along the coast were analyzed using the GIS (geographic information systems) technique and the DSAS model. The four important statistical parameters of the DSAS model utilized in the study area are end point rate (EPR), net shoreline movement (NSM), linear regression rate (LRR), and least median of squares (LMS). The shoreline change analysis for the coast of Subarnarekha and Budhabalanga river estuary area from 1991 to 2022 reveals that 44% of the coast is under accretion, 7% is under stable coast, and 23% is under erosion. According to the findings, the coastal area of the recent study is both progressive and regressive in nature. For the study area, the average rates of shoreline accretion and erosion are 1.05 m and 0.45 m per year, respectively. The study gives information on erosion and accretion near the Subarnarekha and Budhabalanga river estuaries, which will aid in the development of an adaptive shoreline management strategy and coastal vulnerability assessment.

Temporal Shoreline Changes From 1984 to 2022 Along Beymelek Beach and Beymelek Lagoon, Antalya, Türkiye

Coastal zones are important transition zones between land and sea, and the shoreline is subject to dynamic change on both spatial and temporal scales. Accurate measurement and modelling of the shoreline is therefore essential for coastal sustainability and coastal zone management. In this study, the shoreline change of Beymelek Beach and Beymelek Lagoon was analyzed over both short and long periods by using End Point Rate (EPR), Net Shoreline Movement (NSM) and Linear Regression Rate (LRR) statistics from the Digital Shoreline Analyses System (DSAS) tool. The long-term shoreline statistics of the Beymelek Beach indicates that the maximum shoreline accretion was 128.4 m for NSM and 4.3 m/yr for EPR, while the maximum shoreline erosion was -62.6 m for NSM, and -1.8 m/yr for LRR in 1984 and 2022. The maximum shoreline erosion rate of Beymelek Lagoon was -148.5 m for NSM and the maximum shoreline accretion was 5.3 m for NSM between 1984 and 2022. As a result, Beymelek Beach and Beymelek Lagoon have experienced significant shoreline changes over both short and long time periods. Therefore, determining the shoreline change in the study area is crucial for making efficient decisions about the coastal zone and contributing to its sustainability.

Delineation of Shoreline and Associated Land Use/Land Cover Changes along the Coast of Chattogram, Bangladesh Based on Remote Sensing and GIS Techniques

This study aimed at delineating the shoreline by using the Digital Shoreline Analysis System (DSAS 5.0) tool and detected the changes of land use/land cover (LULC) by Google Earth Engine (GEE) platform. The shoreline is divided into two zones, whereas Zone I covered 87.12[Formula: see text]km and Zone II possessed 168.05[Formula: see text]km. According to End Point Rate (EPR), the mean shoreline change rate of Zone I is 3.55[Formula: see text]m/year and Zone II is [Formula: see text]6.84[Formula: see text]m/year. Likewise, based on Linear Regression Rate (LRR), the mean shoreline change rate of Zone I is 5.46[Formula: see text]m/year and Zone II is [Formula: see text]4.71[Formula: see text]m/year, respectively. Apart from that, the Net Shoreline Movement (NSM) recorded in Zone I is 109.42[Formula: see text]m as well as Zone II is [Formula: see text]213.25[Formula: see text]m, which also revealed how much the shoreline has changed during the last 32 years. This study also used the Kalman filter model to forecast the shoreline positions for 20 years. The most destructive signal is that more than 70% of the coastline is vulnerable due to erosion, whereas 6% is highly vulnerable. By contrast, the results of LULC changes demonstrated the increasing trend of water bodies, built up, and agricultural land while vegetation along with bare land is reduced continuously. The overall accuracy is recorded above 88%, and the kappa co-efficient is found above 0.87 for all three years. The outcome of this study will provide fruitful insight into coastal land use management and adaptation measures against the ongoing along with future threats of shoreline changes to coastal ecosystems and livelihoods.

Monitoring and predicting spatio-temporal dynamics of river bankline movements: a case study for land use risk management in the lower Ganga River, India.

Changing the river course in the alluvial plain region is a common phenomenon that may have disastrous consequences. The risk of river bank erosion has increased dramatically during the last few decades. As a result, assessing the river bankline alteration is necessary. The study aims to determine the changes in the bankline in the lower Ganga River. This research presents a novel approach by using the digital shoreline analysis system (DSAS) in conjunction with geospatial data to monitor and predict long-term changes in river banks from 1965 to 2017, providing a comprehensive temporal analysis that is unprecedented in this study area. The study analyzes the bankline change along the river Ganga using DSAS using during the elapsed period. An erosion and accretion zonation was conducted based on the rate of bankline change of the river Ganga in the study area. The rate of bankline shifting was quantified using the endpoint rate (EPR) and linear regression rate (LRR) statistics computed using the DSAS model. The east bank of the Ganga in the study area experienced an average erosion of - 41.17m/year according to the LRR model. Whereas, the west bank eroded an average of - 2.32m/year between 1965 and 2017. 90.54% of the transect lines recorded erosion at the east bank and 53.69% of the transect lines at the west bank recorded erosion computed with LRR. For the assessment of the impact of river bankline change on the LULC of the study area, the future river banklines for 2027 and 2037 were forecasted. The result shows that by 2027 and 2037 about 133.24 and 147 km2 of agricultural land and 7.19 and 11.47 km2 of the built-up area may be affected by river bank erosion respectively. By extending the applications of DSAS and geospatial analytics to encompass predictive and impact assessment capabilities, this study significantly enriches the literature on the management of riverbank erosion and associated land use risks. This research provides important insights that improve river management and planning and enable the formulation of robust strategies to mitigate erosion risks on river banks.

Shoreline morphological change prognostic model based on spatiotemporal framework imagery data on the northern coast of Java, Indonesia

This study focuses on identifying the degree of shoreline changes on the north coast of Java Island (Indonesia), particularly the Batang Regency segment, using multiple data sources: Landsat 9 and 8, Landsat 5 TM, and PlanetScope spanning from 2000 to 2023. The degree of change was obtained by statistically calculating net shoreline movement (NSM), linear regression rate (LRR), and end-point rate (EPR) using the digital shoreline analysis system (DSAS) software. The three rate-of-change statistics were used to calculate the multidecadal shoreline change prediction or projection for the next 10 and 20 years using a Kalman filter-based model with a simple data assimilation technique. Based on these results, NSM indicated that the shoreline experienced a total accretion and erosion of 361.04 and 111.58 m, respectively, from 2000 to 2023. Over these years, the highest accretion rate reached 16.44 m/year (according to LRR) or 15.83 m/year (EPR), while the maximum erosion rate was up to 11.34 m/year (LRR) or 9.43 m/year (EPR). The use of two data sources with different spatial resolutions produces varying statistical values, which depend on the degree of detail and complexity of the data derived from the source imagery. The coastline prognosis model produced with the Kalman filter shows that the entire coastline in Batang Regency will most likely experience an average accretion and erosion of 18.03 and 21.42 m, respectively, in 10 years, while that in the next 20 years will be 26.38 and 33.3 m, respectively.

Geospatial technology based shoreline change analysis (1992–2022) and predictive forecast modeling for 2032 and 2042, utilizing DSAS, along the eastern coast of India

This study presents a comprehensive analysis of shoreline dynamics in the Thanjavur district, focusing on erosion and accretion trends from 1992 to 2022. The coastal region was partitioned based on Taluk boundaries to discern distinct patterns in erosion and accretion. The Peravurani region displayed stability, while the Mettupalayam Coast exhibited modest accretion, influenced by sediment deposition from the Tedakkiar River. Mettupalayam had the highest net shoreline movement (NSM), contrasting with the Mandiripattinam coast's prevalent erosion trend. Areas such as Ammani Chattram and Setubava Chattram coast remained relatively stable, while Ganeshapuram, Sendalapattinam, and Sembalpattinam coasts experienced low accretion linked to the Ambuliar River. The study found that the maximum erosion in the study area is 4.1 m/yr (end point rate (EPR)) and 4.21 m/yr (linear regression rate (LRR)) at the Maravakkadu coastal region, and the maximum accretion is 3.75 m/yr (EPR) and LRR of 4.12 m/yr at the Mettupalayam coast. Employing the Kalman filter, future shoreline projections for 2032 and 2042 revealed heightened erosion and accretion trends, identifying vulnerable areas and distinct accretion patterns. It has been predicted that the eastern part of the coastal stretch erodes towards the land, and the western part is accreting. The dynamic interaction of erosion and accretion in Sendalapattinam underscored historical influences on future projections. However, ongoing erosion on the Maravakkadu coast may entail potential economic consequences. The findings emphasize the need for informed coastal management strategies, integrating historical data and future predictions. This will help maintain the coastal ecosystem and community resilience in the changing shoreline dynamics.

Assessing geomorphological changes in coastal lagoon inlet using geospatial tools: A case study Moulay Bousselham lagoon, Morocco

Coastal monitoring is crucial for coastal management and both sustainable progress and environmental protection. This study aims to assess the morphodynamic changes undergone by an inlet, sandpits, and adjacent beaches of Moulay Bousselham lagoon (Morocco Atlantic coast), considered a RAMSAR site of significant biodiversity. Firstly, a Digital Shoreline Analysis System (DSAS) is applied to monitor shoreline evolution between 1949 and 2021, based on the End Point Rate (EPR) and Linear Regression Rate (LRR) methods, with the study area divided into south and north sides. Secondly, we mapped sandpit areas in the lagoon using recent satellite images and historical aerial photos covering a period of 75 years (1949–2024) within a GIS (Geographic Information System) environment. As a result, the average annual accretion rates on the north side, comprising 735 transects (1.45 km length), are +3.23 m/year (EPR) and +3.26 m/year (LRR). Additionally, the accretion phenomenon is observed in 117 transects, while erosion is recorded in 618 transects with −0.73 m/year and −0.81 m/year for EPR and LRR methods, respectively. The south side, comprising 1085 transects (2.46 km length), shows average annual erosion rates of −0.99 m/year (EPR) and −0.76 m/year (LRR) concerning the south part of the entrance inlet, with 278 transects showing accretion and 807 transects indicating erosion. Moreover, flood-dominated deltas (sandpit) mapping shows significant changes in the sandpit areas at the entrance inlet and inside the lagoon, with the area of accumulation increasing from around 155662,57 m2 in 1949 to 306020,22 m2 in March 2024. Inlet width measurements reveal fluctuations over time, from 53 m in 1949 to 177 m by 1988, reflecting dynamic coastal processes. However, by March 2024, the width decreased to 30 m, indicating sediment blockage and intense siltation. This analysis revealed that these sedimentation trends are mainly controlled by southward-directed littoral transport and the change in inlet position induced by several factors, including tidal currents, wave energy and river flow, particularly during winter seasons and extreme events (marine submersions and flooding). This article will help us to understand the relationship between the evolution of the coastline and its immediate influence on sediment supply to the lagoon.

Exploring shoreline changes and their implications in coastal communities using GIS and remote sensing techniques: The case of eastern beaches of Unguja island, Tanzania

Understanding shoreline dynamics and their impacts is crucial for the successful planning and development of coastal regions. This study focused on the research scarce area of the eastern coast of Unguja island, Tanzania to explore shoreline changes and their implications from 1990 to 2040 using GIS and remote sensing techniques. Four Landsat imagery taken in 1990, 2000, 2010 and 2020 were obtained and processed to determine past shoreline scenarios using Net-Shoreline-Movement (NSM), End-Point-Rate (EPR) and Linear-Regression-Rate (LRR) metrics in the DSAS software. Additionally, the LRR and the Kalman filter model were employed in the same software to determine future shoreline scenarios up to 2040. Overall results by LRR demonstrate that the shoreline of the eastern coast of Unguja was eroding at an average rate 15.560 m/year and its erosion rate is projected to reach 25.648 m/year by 2040. The total land eroded and accreted by EPR was 37,540,702.71 m² and 734,721.8037 m2, respectively. Periodically, high shoreline erosion rates occurred between 2000 and 2010 by the NSM (529.926 m, −798.133 m and −65.230 m) and EPR (53.299 m/year, −78.884 m/year and −6.617 m/year) results. Geographically, our study has identified that a significant portion of shoreline erosion occurs in the northern part of the island and some of its main identified impacts include the destruction of facilities along the coastal zone area. These findings call for the immediate and long-term interventions to mitigate adverse impacts of shoreline erosion and can inform other research in similar areas.

SPATIO-TEMPORAL SCALES OF LAND COVER AND SHORELINE DYNAMICS IN BANAYBANAY, DAVAO ORIENTAL, PHILIPPINES USING AVAILABLE OPTICAL SATELLITE IMAGERY

Abstract. Shoreline dynamics are often the most visible indicators of changes that occur in coastal areas. It is essential to consider a shoreline's physical location while evaluating changes on a temporal and chronological scale. The shoreline in Banaybanay, Davao Oriental, has undergone significant land use changes, leading to negative impacts on related coastal processes, including mariculture conditions in the area. This study aims to determine changes in land cover and shoreline in Banaybanay’s coastal barangays by analyzing satellite images from 1989–2021 using remote sensing, GIS, and Digital Shoreline Analysis Systems (DSAS). The study found that rapid land cover changes in the area were primarily driven by development growth, urbanization, mining, and human activities. The Net Shoreline Movement (NSM), End Point Rate (EPR), and Linear Regression Rate (LRR) results indicated accretion in Banaybanay’s coastal areas, corresponding to an increase in built-ups and barren from 1989–2021. Characterization of land cover and shoreline change revealed high erosion associated with land cover change of barren-water and grassland/brushland-water with a maximum erosion value of −1.19 m/yr. Conversely, very high accretion was mainly characterized by land cover change of water-built-up, barren-built-up, and water-barren with a maximum accretion value of 9.58 m/yr.

Geospatial analysis of shoreline and areal dynamics in the Ganges deltaic island of Bangladesh using the GIS-DSAS technique

Manpura Island, located at the mouth of the Ganges-Brahmaputra-Meghna (GBM) River estuary, is a well-known Ganges deltaic island prone to severe erosion. This study aims to identify shoreline and areal changes in Manpura Island of Bangladesh from 1990 to 2020 using the digital shoreline analysis system (DSAS), a plugin of ArcGIS. The estimation of shoreline variability was primarily described for four segments of the Island: Segment A in the north, Segment B in the west, Segment C in the south, and segment D in the east. It was observed that all four segments of the study area are vulnerable to high rates of shoreline erosion. Landward movement was high in Segment A where Net Shoreline Movement (NSM) was −4000.1 m. Landward movement was also high in Segments B and C with the NSM of −1084.7 m and −1021.6 m, respectively. According to the End Point Rate (EPR) and Linear Regression Rate (LRR), Segment A exhibited a very dynamic feature, with an average shoreline change rate of −24.7 m/yr and −24.2 m/yr, respectively. In Segment C, the average shoreline change rate was −8.5 m/yr for EPR and −9.1 m/yr for LRR. Approximately 392 transects were constructed in the four segments of the island, with approximately 330–334 showing landward movement and 58–62 showing seaward movement. Nevertheless, the island lost about 28.4 km2 in land area and gained only around 2.3 km2 of its original landmass during the study period. The total loss of shoreline length was about 11.5 km (0.4 km/yr), while the total loss of land area was about 26.1 km2 (0.9 km2/yr). The main factors of shoreline change in the study region is likely to be high river discharge, stormy climate and, human interference. The results of this study are useful for the proper management and planning of Manpura Island. However, they can also be used in statistical approaches to forecasting possible shoreline locations in the future under double pressure of climate change and human activities.

Geospatial analysis of shoreline changes in the Oman coastal region (2000-2022) using GIS and remote sensing techniques

This research introduces an innovative method employing the Canny edge detector for automatic and precise coastline extraction, aiming to analyze spatial and temporal variations in the Oman coastline from 2000 to 2022 using GIS and remote sensing (RS) techniques. Focusing on both multi-decadal and short-term periods, the study aims to detect accretion and erosion rates through the observation and interpretation of coastal changes. Utilizing the Digital Shoreline Analysis System and LANDSAT imageries, Shoreline changes have been quantitatively evaluated using three distinct approaches: Linear Regression Rate (LRR), End Point Rate (EPR), and Net Shoreline Movement (NSM). The dynamic nature of the Oman coastal region necessitates a comprehensive understanding of its evolving coastline. Our investigation applies digital shoreline analysis to discern shifts in the coastline’s position, employing a multiple regression approach for quantifying the rate of coastal change. To facilitate automatic shoreline extraction, various methods were experimented with, ultimately determining the Canny Edge algorithm’s superiority in yielding precise results. The paper outlines the monitoring procedures for the coastal area and analyzes coastline changes using geospatial techniques. This analysis provides valuable insights for the planning and management of the Oman shore. Furthermore, the proposed model’s applicability is rigorously tested against other generic edge detection algorithms, including Sobel, Prewitt, and Robert’s techniques. The conclusive findings demonstrate that our model outperforms these alternatives, particularly excelling in the accurate detection of the coastline. This research contributes to a deeper understanding of coastal dynamics and offers a robust methodology for coastal monitoring, with implications for effective planning and management strategies in the Oman shore region.

Investigation of the effects of small fishing ports on the shoreline: a case study of Samsun, Turkey

Shoreline change analysis is crucial for identifying coastal issues and understanding their underlying causes. This study focuses on investigating the coastal impacts of the Derekoy Fishing Port in Samsun, a city located on the Black Sea coast of Turkey. Temporal changes between 1984 and 2021 were analyzed using Landsat-5 TM/Landsat-8 OLI satellite images in conjunction with image processing and geographic information systems (GIS). Net shoreline movement (NSM), shoreline change envelope (SCE), end point rate (EPR), and linear regression rate (LRR) methods were used to investigate the changes in the shoreline. Polygon overlay analysis was utilized to determine the areas of erosion and accretion. The results indicate that prior to the port's construction, the coast remained relatively stable during the period of 1984–1995. However, sediment accretion occurred on the updrift side of the port, while erosion intensified on the downdrift side during the port's construction from 1995 to 2004. Despite the implementation of coastal protection structures to combat erosion, complete prevention was not achieved, and erosion shifted further eastward. Throughout 1984–2021, approximately 15.62 hectares of beaches were lost due to erosion, with a maximum value of -56.2 m recorded. The coastal erosion and the construction of coastal protection structures have disturbed coastal morphology and resulted in various environmental and socio-economic issues along the 19 Mayis and Atakum beaches. This study reveals the significant consequences of a small fishing port built without proper planning and adequate precautions, drawing attention to the problems.

Coastline Monitoring and Prediction Based on Long-Term Remote Sensing Data—A Case Study of the Eastern Coast of Laizhou Bay, China

Monitoring shoreline movements is essential for understanding the impact of anthropogenic activities and climate change on the coastal zone dynamics. The use of remote sensing allows for large-scale spatial and temporal studies to better comprehend current trends. This study used Landsat 5 (TM), Landsat 8 (OLI), and Sentinel-2 (MSI) remote sensing images, together with the Otsu algorithm, marching squares algorithm, and tidal correction algorithm, to extract and correct the coastline positions of the east coast of Laizhou Bay in China from 1984 to 2022. The results indicate that 89.63% of the extracted shoreline segments have an error less than 30 m compared to the manually drawn coastline. The total length of the coastline increased from 166.90 km to 364.20 km, throughout the observation period, with a length change intensity (LCI) of 3.11% due to the development of coastal protection and engineering structures for human activities. The anthropization led to a decrease in the natural coastline from 83.33% to 13.89% and a continuous increase in the diversity and human use of the coastline. In particular, the index of coastline diversity (ICTD) and the index of coastline utilization degree (ICUD) increased from 0.39 to 0.79, and from 153.30 to 390.37, respectively. Over 70% of the sandy beaches experienced erosional processes. The shoreline erosion calculated using the end point rate (EPR) and the linear regression rate (LRR) is 79.54% and 85.58%, respectively. The fractal dimension of the coastline shows an increasing trend and is positively correlated with human activities. Coastline changes are primarily attributed to interventions such as land reclamation, aquaculture development, and port construction resulting in the creation of 10,000.20 hectares of new coastal areas. Finally, the use of Kalman filtering for the first time made it possible to predict that approximately 84.58% of the sandy coastline will be eroded to varying degrees by 2032. The research results can provide valuable reference for the scientific planning and rational utilization of resources on the eastern coast of Laizhou Bay.

Evolution of shoreline dynamics in Betoya Bay, home of the Nador West Med port, Morocco using the DSAS technique

Shorelines are subject to constant changes due to natural and anthropogenic factors. Monitoring these changes is imperative for effective coastal management, environmental protection, and sustainable development. This work aims to provide detailed insights into the morphology and transformation of the shoreline within Betoya Bay, home to the strategically positioned Nador West Med (NWM) port complex, which is pivotal in enhancing maritime transport within the Mediterranean region. To achieve this, we have integrated remote sensing data, using LANDSAT satellite imagery from 1993 to 2023, and GIS applications with the help of the Digital Shoreline Analysis System. Shoreline change rates are assessed using End Point Rate (EPR) and Linear Regression Rate (LRR). The resulting maps enable us to pinpoint the shoreline changes after dividing the study area into two distinct zones. The results underscore the moderate dynamic nature of Betoya Bay's coastline, where various zones experience erosion and accretion, with erosion and accretion rates reaching -1.18 m/year and +1.4 m/year, respectively.

TENDÊNCIAS RECENTES DA LINHA DE COSTA NA MARGEM LESTE DO ESTUÁRIO MÉDIO DO RIO PARÁ

The main objective of this article is to quantify the erosion and accretion rates on the eastern margin of the middle Pará Estuary within 32 years (1987, 1993, 1999, 2004, 2008, 2013, and 2019) with the use of remote sensing and data Digital Shoreline Analysis System (DSAS) extension. These methodological procedures recently applied in the Amazon region are effective in the search for intended results. To calculate with significant accuracy the rates of CL changes, select the parameters Net Shoreline Movement (NSM), Linear Regression Rate (LRR), and End Point Rate (EPR) to obtain the variations. In the middle estuary, the rates showed a tendency towards CL retreat in the onshore direction, with an average rate of -38 m and an average accretion rate of 22.97 m prevailing on Mosqueiro Island, related to average rates of variation of -0.58 m/ year (EPR) and -0.54 m/year (LRR) and in Santo Antônio do Tauá with LRR and EPR parameters identifying average rates of variation of -1.67 m/year (LRR) and -1.55 m/year (EPR). Only on Colares island, there was a tendency to accretion, with an average erosion rate of -96.29 m and an average accretion rate of 116.49 m, where the maximum accretion and erosion rates are 405.61 m and -396.87 m, respectively. Keywords: Eastern Amazon, Coastal Dynamics, Estuarine Environment, LANDSAT.

Shoreline Change Assessment in the Orashi River, Rivers State, Nigeria, using the Digital Shoreline Analysis System (DSAS)

Shoreline change profoundly impacts coastal geology and coastal communities. This study, spanning three decades from 1992 to 2022, employed the Digital Shoreline Analysis System (DSAS) to assess the Orashi River shoreline dynamics in Nigeria. Using Landsat imagery data from the United States Geological Survey (USGS) and ArcGIS 10.6, DSAS 5.0 software was utilized for analysis. Various statistical methods, including Linear Regression Rate (LRR), Weighted Linear Regression (WLR), End Point Rate (EPR), Net Shoreline Movement (NSM), and Shoreline Change Envelope (SCE), quantified shoreline changes. The findings consistently reveal significant shoreline regression. LRR, -1.78 to -1.07, highlights continuous landward movement, signifying erosion’s persistent impact. WLR rates reaffirm this trend, closely mirroring the range of -1.78 to -1.07. EPR, -2.79 to -1.29, further underline the erosional trend, emphasizing substantial inland shifts. NSM, ranging from -48.66 to -20.30, signifies substantial shoreline retreat, showcasing erosion’s profound effect. The NSM, varying from 0.69 to -11.50, illustrates dynamic shoreline movement with varying degrees of erosion. The outcomes identify prevalent erosion, particularly in Very High Erosion (VHE) areas, while High Accretion (HA) and Very High Accretion (VHA) zones experience shoreline gain. These classifications inform coastal management strategies, urging protective measures for VHE areas and development opportunities in HA and VHA zones. The variability in shoreline change underscores coastal dynamics’ complexity. This study contributes to understanding the Orashi River’s shoreline processes, guiding sustainable coastal management and environmental conservation efforts. Continued monitoring and research are crucial for adapting to the evolving coastal landscape’s impact on the environment and local communities.

Analysis of shoreline changes in the severe storm surge region of upper Coromandel coast, India, using Remote sensing (RS) and Geographic information system (GIS)

Coastlines have been subject to ongoing vulnerability from natural disasters, resulting in erosion and accretion occurring at varying intervals. The impacts of human activities and alterations in natural processes, including those induced by climate change, exacerbate the existing challenges faced along coastal regions. The present study aimed to analyze the changing shoreline along the Bapatla coastal tract in the upper coromandel coast of Andhra Pradesh due to erosion and accretion using the DSAS toolbar in ArcGIS software. Multiple statistical methods are available in DSAS; the present study confined attention to the end point rate (EPR), linear regression rate (LRR), and net shoreline movement (NSM) for this investigation. The Nizampatnam Mandal had the greatest erosion rate (-16.8 m/yr) and accretion rate (10.5 m/yr), according to EPR, as well as the highest erosion rate (-16.7 m/yr) and accretion rate (10.4 m/yr) according to LRR. As per NSM, between 1990 and 2020, the highest erosion and accretion was seen again in Nizampatnam. The shoreline at Nizampatnam either retreated by as much as -285.2 meters or advanced by 211.1 meters. The research indicated that the Bapatla district's shoreline is susceptible to erosion and accretion. The present investigation revealed that the coastal region of Bapatla district exhibits susceptibility to both erosion and accretion phenomena. The findings of the present study hold significant implications for professionals in the fields of coastal science, engineering, and administration. The findings are of utmost importance in the development of sustainable approaches for coastal management.

Groundwater Variability Along with The Varying Coastline of Thiruvanathapuram City

Shoreline change is a constantly evolving phenomenon that threatens people and their livelihoods around the globe. India observes this phenomenon strongly at different locations being a tropical peninsular country with 6635kms of coastline. This study tried to analyze the effect of shoreline change on surrounding ground water reserves along Thiruvanathapuram coast in Kerala district of India. Net changes in coastline positions are statistically calculated and observed using Linear Regression Rate (LRR). The shoreline change rate shows most of the region are undergoing erosion, only few accretions or land formation are observed which was mostly artificially formed due to harbor building. The highest erosion rate in terms of LRR was -7m/year and highest accretion was 28m/year. We compared the shoreline change with groundwater variability along the coast and also groundwater salinity using electrical conductivity as the factor. The study observed decreasing trend of groundwater along the eroding coastline. The study also predicted decadal shoreline change along the Thiruvanathapuram coast was predicted using Kalman filter model.

Using RS and GIS Techniques to Assess and Monitor Coastal Changes of Coastal Islands in the Marine Environment of a Humid Tropical Region

Vypin, Vallarpadam, and Bolgatty are significant tropical coastal islands situated in the humid tropical Kerala region of India, notable for their environmental sensitivity. This study conducted a comprehensive assessment of shoreline alterations on these islands by integrating Remote Sensing (RS) and Geographic Information Systems (GIS) techniques. Utilizing satellite imagery from the LANDSAT series with a spatial resolution of 30 m, the analysis spanned the years from 1973 to 2019. The Digital Shoreline Analysis System (DSAS) tool, integrated into the ArcGIS software, was employed to monitor and analyze shoreline shifts, encompassing erosion and accretion. Various statistical parameters, including Net Shoreline Movement (NSM), End Point Rate (EPR), and Linear Regression Rate (LRR), were utilized to evaluate these changes. Additionally, the study aimed to discern the root causes of shoreline modifications in the study area, encompassing disturbances and the construction of new structures on these islands. The results conclusively demonstrated the substantial impact endured by these coastal islands, with accretion on both sides leading to the creation of new landmasses. This manuscript effectively illustrates that these islands have experienced marine transgression, notably evidenced by accretion. Anthropogenic activities were identified as the primary drivers behind the observed shoreline changes, underscoring the need for careful management and sustainable practices in these fragile coastal ecosystems.