Implications For Coastal Zone Management Research Articles

Monitoring sediment transport pathways from an artificial nearshore berm, South Padre Island, Texas, USA, August 2018 to November 2019—Implications for coastal management

During August 2018 – November 2019, the transport pathways of dredge material from a specially constructed nearshore feeder berm were investigated as part of a collaborative study by the City of South Padre Island, U.S. Army Corps of Engineers–Galveston District, U.S. Geological Survey, Partrac GeoMarine Inc., and Texas A&M University, into the efficacy of beneficial use dredge material (BUDM) as a method of replenishing the beach profile and shoreface at South Padre Island, Texas with sediment. Dual-signature (fluorescent and ferrimagnetic) tracer particles, designed to be hydraulically equivalent to the dredge material, were placed on the berm, and a sampling program was initiated to monitor the spatiotemporal movement of tracer particles under the influence of the prevailing hydrodynamic regime. Wave and current data were collected and were used together with available metocean data to identify the forcing mechanisms of sediment transport; improved understanding garnered from the consideration of multiple datasets can be used to inform future coastal management decisions.Tracer analysis results indicated low magnitude, shoreward transport of dredge material from the berm and along shore transport in both northerly and southerly directions. Small amounts of tracer detected in beach face samples demonstrated connectivity between the constructed feeder berm and the shoreface. However, the generally low tracer concentration within beach face samples indicated low rates of sediment transport for berm sediments, and a low magnitude sediment transport pathway from the berm directly to the beach face, with possible storage of sediment in the nearshore bar system.Given that the berm was at or beyond the closure depth and considering the relatively weak prevailing near bottom hydrodynamic conditions, the potential for sediment to be mobilized and transported during the study period was generally low. Periods of higher energy waves, driven by north-northwest winds, were identified as a key driver of sediment transport but due to the infrequent nature of these events the sediment transport regime across the area of interest was temporally limited. Longshore movement of sediment was both north and south, mainly dependent on prevailing wind directions and resulting longshore currents.We discuss implications for coastal zone management and the use of feeder berms as an artificial beach nourishment mechanism to replenish sediments lost by coastal erosional processes. The insight into nearshore emplacement of material can be used by local governments and coastal managers to optimize the efficacy of berm emplacement and implement such schemes as a cost-effective nourishment option, or when onshore placement of material is not feasible.

Diversity of property regimes of Mediterranean coastal lagoons in S. France; implications for coastal zone management

We provide a cartography of the current property regimes of permanent coastal lagoons along the coastlines of the Mediterranean Sea for continental France and Corsica, which include both private and public properties. In France, for the latter, the State Domain Code and the General Code of the property of public persons make a clear difference between Public Domain and private property of the different public entities. Public domain represents property that is imprescriptible and inalienable, i.e. the property rights cannot be changed in the future and neither transferred nor sold to somebody else. In contrast, private properties of public entities can be sold or transferred to thirds. Maritime Public Domain (DPM) was created since 1681. DPM has accommodated Public Domain for the French coastal lagoons following their legal definition as “salty ponds (French étangs salés) with a direct, natural and permanent connection with the sea”. However, private landlords battled juridically with the State for centuries both by attacking the pertinence of this definition and claiming ancestral property rights. As a result, before 1980, more than half of the coastal lagoons comprised private properties, representing about a quarter of the lagoon surface. Twelve of 40 coastal lagoons comprise DPM, mainly the larger lagoons (e.g., Salses-Leucate, many lagoons close to Narbonne, Thau lagoon, Berre lagoon), representing 65% of the total lagoon surface. Since its foundation in 1975, the Conservatoire du Littoral, a public body in charge of coastal nature protection, has bought private coastal lagoons properties in twenty of 40 lagoons, representing 22% of the total lagoon surface. These have been designated as inalienable and imprescriptible “Public Domain of the Conservatoire”, safeguarded for nature conservation purposes. Nowadays, private ownership still persists in 13 lagoons representing 3.3% of total surface. The Coastal lagoons in Roussillon (Etangs du Canet and Salses-Leucate), the Hérault department, in the Camargue and in Corsica currently show variable and sometimes fragmented ownership (in addition to the Conservatoire, DPM, private ownership, municipalities, departments). Fragmented ownership is a clear difficulty for the integrated management of coastal lagoons. With currently, 87% of the coastal lagoons as Public Domain, public law and the environmental code have to evolve to tackle the challenges for the conservation and management of coastal lagoons and their connectivity with the other ecosystems on land and in the sea.

Extreme storm tides in the German Bight (North Sea) and their potential for amplification

Abstract. Storm tides are a major hazard for the German North Sea coasts. For coastal protection and economic activities, planning information on the probability and magnitude of extreme storm tides and their possible future changes is important. This study focuses on the most extreme events and examines whether they could have become more severe under slightly different conditions while still remaining within physical plausibility. In the face of a limited number of observational data on very severe events, an extensive set of model data is used to extract most extreme storm tide events for locations in the German Bight, in particular Borkum and the Ems estuary. The data set includes water levels and respective atmospheric conditions from a hindcast and future climate realizations without sea level rise describing today's and possible future conditions. A number of very severe events with water levels exceeding those measured near Borkum since 1906 are identified in the data set. A possible further amplification of the highest events is investigated by simulating these events for the North Sea with different phase lags between the astronomical tide given at the open model boundaries and the wind forcing. It is found that superposition of spring tide conditions, different timing of the astronomical high water and atmospheric conditions during the highest storm event would cause an enhancement of the highest water level up to about 50 cm. The water levels of the two highest events from the data set are used to analyse the effects in the Ems estuary using a high-resolution model of the German Bight. Additionally, the influences of an extreme river runoff and of sea level rise are studied. The extreme river runoff of 1200 m3 s−1 increases the highest water levels by several decimetres in the narrow upstream part of the Ems estuary. This effect diminishes downstream. The sea level rise increases the water level in the downstream part of the Ems estuary by the amount applied at the model boundary to the North Sea. In the upstream part, its influence on the water level decreases. This study may serve as a first step towards an impact assessment for severe storm tides and towards implications for coastal zone management in times of climate change.

Rehabilitating mangrove ecosystem services: A case study on the relative benefits of abandoned pond reversion from Panay Island, Philippines

Mangroves provide vital climate change mitigation and adaptation (CCMA) ecosystem services (ES), yet have suffered extensive tropics-wide declines. To mitigate losses, rehabilitation is high on the conservation agenda. However, the relative functionality and ES delivery of rehabilitated mangroves in different intertidal locations is rarely assessed. In a case study from Panay Island, Philippines, using field- and satellite-derived methods, we assess carbon stocks and coastal protection potential of rehabilitated low-intertidal seafront and mid- to upper-intertidal abandoned (leased) fishpond areas, against reference natural mangroves. Due to large sizes and appropriate site conditions, targeted abandoned fishpond reversion to former mangrove was found to be favourable for enhancing CCMA in the coastal zone. In a municipality-specific case study, 96.7% of abandoned fishponds with high potential for effective greenbelt rehabilitation had favourable tenure status for reversion. These findings have implications for coastal zone management in Asia in the face of climate change.

Trust and knowledge exchange in coastal settings

Integrated coastal zone management (ICZM) involves multiple stakeholders operating through multiple processes and levels. This makes ICZM challenging. Trust is a critical ingredient for ensuring that the diverse understandings, perspectives and forms of knowledge about the coast are appropriately considered in decision-making. However, the number and diversity of stakeholders with an interest in the coast means that building and maintaining trust is challenging. Drawing on insights from 42 semi-structured interviews with stakeholders involved in coastal management in Victoria, Australia, this paper contributes to an improved understanding of the importance of trust in coastal zone management and what might be done to enhance it. In doing so, the importance of trust in coastal zone management is reinforced; stakeholders’ perspectives on who they trust to obtain advice from, and why, are unpacked; and the broader implications for coastal zone management are discussed.

MONITORING COASTLINE CHANGE IN THE RED RIVER DELTA USING REMOTELY SENSED DATA

This study focuses on the use of remotely sensed data for monitoring coastline changes in the Red River Delta during the 1998 to 2008 period. For the satellite image data processing, the shoreline was defined as the mean sea level on the muddy coast where the tide is the dominant dynamic factor and as the mean high sea level on the sandy coast where the ocean waves are the dominant dynamic factor. A GIS approach was used for the quantitative analysis of coastline change. It was observed that the coastline change in the Red River Delta underwent complicated changes during this 10 year period. In this period, the accretion rate in Red River Delta coastal area was about 10,256ha and the erosion rate was about 542ha. In the Hai Hau and Hau Loc coastal areas, erosion occurred in a large scale and was very intense. Along other coastlines of the Red River Delta, sediment accretion dominated at rates of over 30m/year. These zones of varying erosion and accretion have important implications for coastal zone management in the Red River Delta region.

Implications of multi-scale sea level and climate variability for coastal resources

While secular changes in regional sea levels and their implications for coastal zone management have been studied extensively, less attention is being paid to natural fluctuations in sea levels, whose interaction with a higher mean level could have significant impacts on low-lying areas, such as wetlands. Here, the long record of sea level at Key West, FL is studied in terms of both the secular trend and the multi-scale sea level variations. This analysis is then used to explore implications for the Everglades National Park (ENP), which is recognized internationally for its ecological significance, and is the site of the largest wetland restoration project in the world. Very shallow topographic gradients (3–6 cm per km) make the region susceptible to small changes in sea level. Observations of surface water levels from a monitoring network within ENP exhibit both the long-term trends and the interannual-to-(multi)decadal variability that are observed in the Key West record. Water levels recorded at four long-term monitoring stations within ENP exhibit increasing trends approximately equal to or larger than the long-term trend at Key West. Time- and frequency-domain analyses highlight the potential influence of climate mechanisms, such as the El Nino/Southern Oscillation and the North Atlantic Oscillation (NAO), on Key West sea levels and marsh water levels, and the potential modulation of their influence by the background state of the North Atlantic Sea Surface Temperatures. In particular, the Key West sea levels are found to be positively correlated with the NAO index, while the two series exhibit high spectral power during the transition to a cold Atlantic Multidecadal Oscillation (AMO). The correlation between the Key West sea levels and the NINO3 Index reverses its sign in coincidence with a reversal of the AMO phase. Water levels in ENP are also influenced by precipitation and freshwater releases from the northern boundary of the Park. The analysis of both climate variability and climate change in such wetlands is needed to inform management practices in coastal wetland zones around the world.

Spit Dynamics along the Central West Coast of India: Implications for Coastal Zone Management

HEGDE, V.S.; NAYAK, S.R.; SHALINI, G.; KRISHNAPRASAD, P.A.; RAJAWAT, A.S.; GIRISH, K.H., and TEJASWINI, B., 2012. Spit dynamics along the central west coast of India: Implications for coastal zone management.Spit growth is observed across many rivers of the central west coast of India. Studies on the seasonal dynamics of the spits of the central west coast of India on the basis of the multidate satellite images LISS III, landsat™ data, panchromatic camera (PAN) data etc. in a geographic information system (GIS) environment using ERDAS imagine 9.0 version followed by field-check and wave data analysis have been discussed in this paper. All types of spits such as paired spits, winglike spits, single spits, etc. are observed along the coast of Karnataka, central west coast of India. Spit growth is responsible not only for shifting of the river mouths, but also for rapid changes in estuarine morphology and in turn on the sedimentation process. It is observed that river mouths with a spit across them have a submerged bar in front of them, whereas rivers devoid of spits are also devoid of submerged bars in front of them. This spatial association of spit and submerged bar is believed to have a genetic relationship. Along the coast many perpendicular faults and uplifts have been observed. Rate of spit growth, along with their direction and inland drainage pattern, suggest a role of sea-level changes and tectonic control in addition to alongshore currents. Rapid spit growth is observed near the inferred tectonic axis. Seasonal dynamics and modification in the spit configuration are related to alongshore drift as well as the wave refraction around the mouth of the rivers.

Local democracy implications for coastal zone management—A case study in southern Norway

Stakeholder participation is frequently recommended to ensure that public values are taken into account in the decision-making processes. However, few attempts have been made to analyse the extent to which increasing stakeholder participation actually leads to better representation of the public values. The main aim of this study is to obtain more insights about reasons why the most frequently applied form of stakeholder participation, i.e. the public hearings, may fail in representing the general public views and values when applied at a local level. A case study was conducted on policy formulations and decision-making in the coastal zone on the island Flekkerøy in southern Norway. Local- and regional-public authorities contributed in in-depth interviews and with written documentation to inform about a comprehensive stakeholder participation process that took place in the early 1990s. The main findings include that landowner interests, and not public views and values, were legitimised during the participatory process because of: (1) the landowner's strong local social power among inhabitants, (2) the design of the participatory processes favouring the landowner interests, (3) the personal relations between local landowners and public managers, and (4) the low representation of public views and values due to a problem of scale, i.e. the NIMBY syndrome. Based on our experience, we recommend improving representation of public views by changing the frequently applied participatory processes to also include citizens in addition to interest groups and experts.

Coastal habitat support to fish and fisheries in Sweden: Integrating ecosystem functions into fisheries management

This study adopts an interdisciplinary approach, where ecological data on habitat structure and fish populations are combined with results from economic valuation case studies to assess effects of habitat disturbance. The focus is on three major habitats (soft sediment bottoms, seagrass beds and rocky bottoms with macroalgae), five fish species (cod, plaice, eel, mackerel and sea trout) and three types of fisheries (commercial, subsistence and recreational fisheries). The results have important implications for coastal zone management, demonstrating both ecologically and economically how coastal habitats support fisheries.

Defining ‘vulnerability’: conflicts, complexities and implications for Coastal Zone Management

Defining ‘vulnerability’: conflicts, complexities and implications for Coastal Zone Management

Genetic Population Structure of Fishes: Implications for Coastal Zone Management

Genetic Population Structure of Fishes: Implications for Coastal Zone Management

Genetic Population Structure of Fishes: Implications for Coastal Zone Management

The pattern for distribution of genetic variation within and between populations is referred to as the genetic population structure of the species. To avoid depletion of genetic resources sustainable management should be based on knowledge of this structure. We discuss key aspects of genetic population structure in the context of identifying biological units for fisheries management, suggesting three basic types of structuring: distinct populations; continuous change; and no differentiation. The type of structure determines how units for genetically sustainable management are to be identified. We also review what is currently known regarding the genetic population structure of fishes exploited in the Swedish part of the Baltic Sea, and conclude that sufficient genetic information is lacking for most of the species. This is a serious problem, particularly considering that populations of several commercially exploited fishes are declining and some exhibit recruitment problems. For six species, Atlantic herring, Atlantic salmon, brown trout, European eel, turbot, and pike, sufficient genetic data are available to provide at least basic information on genetic structure and genetic units for biologically sustainable use. Current management practices do not sufficiently consider these data.

The Potential of a Legislative Approach to Managing Beach Use: The Case of Beach Bylaws in the Republic of Ireland

The ways in which people use beaches have important implications for coastal zone management, and in order for beach use to be sustainable, it often needs to be managed. The degree and mode of management depends on the circumstances of the beach, region, and country in question. The present legislation and coastal zone management framework in Ireland has shortcomings when in comes to managing beach use. One way of working within the present system to improve coastal management is through the use of bylaws managing beach use. They provide an opportunity for an integrated management approach that can focus on beach use, reflect the needs of the local community, and avoid the problems caused by the land?sea divide and the division of responsibility in the coastal zone.

Coastal Changes Over the Past 200 Years Around Ovalau and Moturiki Islands, Fiji: Implications for coastal zone management

The islands Ovalau and Moturiki in central Fiji are selected for the investigation of coastal change over the past c. 200 years. Although having coastal environments typical of many tropical Pacific Islands, Ovalau and Moturiki are also atypical because they experienced urban and infrastructural developments before most other parts. The associated records enable recent coastal changes to be discerned more clearly here than has been possible elsewhere. The islands are surrounded by coral reef, the configuration of which accounts for variations in vulnerability of their coasts to erosion. Interviews were conducted in each of 22 settlements along the islands' coasts and information obtained about recent coastal change. Mangroves are concentrated along leeward coasts, although they have been cleared from many windward coasts in the last 40 + years, causing shoreline erosion to be initiated/accelerated. Most shoreline-protection initiatives (vegetation planting and seawall construction) have failed. Three major management implications of the study are discussed. Firstly, there is a need to redefine the nature of the interactions between coastal inhabitants and coastal ecosystems, so that environments are sustainably developed; and specifically that reefs are conserved and shoreline vegetation (especially mangroves) is effectively replanted. Secondly, information about appropriate design and composition of artificial structures for shoreline protection needs to be made available to the local communities who construct most of them. Thirdly, alternative sources of sand and rock aggregate to those whose extraction aggravates shoreline erosion should be sought.

An evaluation of Louisiana superport studies and implications for coastal zone management

Abstract The economic and environmental consequences of a proposed Louisiana superport have been studied by researchers during the last three years. These studies provided technical information and management alternatives. Management alternatives included state control to avoid multiple superport developments, details for an Environmental Protection Plan, comparisons of onshore and offshore sites, and planning for ancillary development. Policy decisions which resulted include many of the recommendations of the research. It is suggested that environmental research can influence policy decisions and limit the options available to a decision maker provided some legal structure is created, quality control is implemented, and technological and environmental problems are recognized. Various analytical tools, such as energy cost accounting, group critique, and simulation models, have wide application for use in coastal zone management.