Land Loss In Coastal Louisiana Research Articles

A Neopragmatic Perspective on the Processual Nature of Landscape—Coastal Land Loss in Louisiana in the Context of Scientific Findings, Social Patterns of Interpretation, and Individual Experience

The changes on the Louisiana coast due to land loss can be understood as a process, and the social construction of these processes is highly complex. Due to this complexity, we will examine these social patterns of interpretation as well as individual experiences of coastal land loss in Louisiana within a neopragmatic meta-theoretical framework using several methods, data, researcher perspectives, forms of representation, and theories, with a special focus on the construction of coastal land loss by the media. For this purpose, comments below a YouTube video on a hurricane event on Grand Isle, Louisiana, as well as on-site interviews with people affected by coastal land loss, were qualitatively analyzed. The results were interpreted with the help of various theories such as the theory of three landscapes, Dahrendorf’s conflict theory, Bourdieu’s theory of social capital, and Luhmann’s autopoietic systems theory. The research reveals patterns of interpretation, categorization, and evaluation of processes from an internal and external perspective that are highly morally charged.

LONG TERM MORPHOLOGIC MODELLING OF DELTA DEVELOPMENT IN BRETON SOUND RESULTING FROM A PROPOSED DIVERSION STRUCTURE

Sediment deprivation, hydrologic alteration, subsidence, sea level rise, and saltwater intrusion have been causing significant land loss in coastal Louisiana. Breton Sound combined with the nearby Barataria Bay, and Mississippi River Delta have lost approximately 1800 square kilometers (or 447,000 acres) of land, representing one of the highest land loss rates in the world since the 1930s when the Mississippi River was leveed. To address this problem, the Coastal Protection and Restoration Authority (CPRA) initiated several sediment diversion projects in the Lower Mississippi River (LMR). The Mid- Breton Sediment Diversion (MBrSD) project is one of the costal restoration projects proposed to restore natural processes in Breton Sound, which can strategically reestablish hydrologic flows, carry land-building sediments, nourish marshes and sustain land.

Cartographic Representations of Coastal Land Loss in Louisiana: An Investigation Based on Deviant Cartographies

The claim of topographic cartography to represent things of relevance and at the same time of certain permanent material persistence is challenged by the processes of coastal land loss in Louisiana. This example is used to discuss central points of critical cartography, such as a positivist worldview of cartography, its state-boundedness, and the construction of relevance. These aspects are taken (meta-functionally) as the occasion for reflection and further development of cartography in the sense of post-critical cartography sensitive to hybridities, complexities and contingencies. In doing so, we draw on reflections on deviant cartographies that foreground the consideration of whether changes in cartography have proven professionally or socially useful, suitable, and usable, without resorting to the notion of a comprehensive paradigm shift. The need is particularly evident in the case of land loss in Louisiana, where there is a constantly changing physical space that hardly allows for the construction of a clear dividing line between land and water areas, as is also evident from the analysis of historical and current maps that reflect topographies.

Relationship between Growth Faults, Subsidence, and Land Loss: An Example from Cameron Parish, Southwestern Louisiana, USA

O'Leary, M. and Gottardi, R., 2020. Relationship between growth faults, subsidence, and land loss: An example from Cameron Parish, Southwestern Louisiana, USA. Journal of Coastal Research, 36(4), 812–827. Coconut Creek (Florida), ISSN 0749-0208.This study investigates the relationship between faulting, subsidence, and land loss in coastal Louisiana. A methodology that integrates three-dimensional (3D) seismic data, well logs, high-resolution topographic mapping (LIDAR), and historical aerial photography is successfully developed to identify fault-related geomorphic changes in southwestern Louisiana's Chenier Plain. Analysis of a 3D seismic survey and well logs reveals the presence of 10 normal faults that form an east-west graben in the middle of the study area. Well logs were used to further constrain the geometry of the faults. Shallow water well logs were used to map the faults at shallow depth, below the resolution of the seismic survey. Fault traces were extrapolated to the surface by maintaining constant dip and projected on LIDAR data. Elevation profiles derived from the LIDAR were conducted across the different faults, and results show that a distinct difference between the upthrown and downthrown sides of the faults occurs. Historical aerial photographs were used to investigate any change in geomorphology from 1953 to 2017 within the study area. Results reveal the occurrence of water bodies on the immediate downthrown sides of suspected fault traces. These findings suggest that faulting influences and focuses areas where subsidence is happening and subsequent land loss may occur, and detailed understanding of active shallow faulting in coastal areas can be used to identify regions that are at risk of land loss.

Visuals as a method of coastal environmental communication

This study explores the influence of visual imagery on individuals' perception of complex scientific information on coastal land loss. It investigates how mass media channels use visual frames to convey an environmental issue's outcomes and how these frames might influence perceptions of issue urgency and issue importance. The primary message frames explored in this study were gain/loss frames and temporal context. A content analysis was conducted to collect online images of coastal land loss in Louisiana and the potential message frames used to communicate this issue's outcomes to the public were identified for each image and coded. Focus group discussions were then used to evaluate the effectiveness of these message frames. Results suggest that visual cues can shape public understanding of coastal change and its risk to coastal communities. Particularly, images that refer to future environmental conditions (temporal context) are more likely to convey the urgency and importance of an issue. Images that emphasize environmental and economic losses may be more engaging to an audience, however these types of images may also reduce motivation to mitigate losses. Willingness to support environmental solutions appears to be a result of public's ability to visualize short-term goals and successes. Best practices for coastal managers to produce and deliver environmental imagery are discussed.

Deltaic morphodynamics and stratigraphic evolution of Middle Barataria Bay and Middle Breton Sound regions, Louisiana, USA: Implications for river-sediment diversions

River-sediment diversions have been recognized as a key strategy for offsetting land loss in coastal Louisiana. Recently, much attention has been focused on sediment capture from the main stem river and conveyance of that material through diversion outflows. Yet, the performance and long-term feasibility of diversions as land-building agents also hinges upon the subsurface stratigraphic architecture of receiving basins, a concept that has largely been unexplored. A major core collection and analysis program was undertaken to study the geological properties of substrates in the Middle Barataria Bay and Middle Breton Sound diversion receiving basins, Louisiana, USA. Over a region of ∼200 square kilometers in both basins, 50 vibracores up to 5.5 m in length were collected in spring and summer of 2015. Cores were logged for bulk density and imaged with a Geotek Multi Sensor Core Logger. Split cores were then subsampled for granulometry, organic content, and 14C dating. Both receiving basins are characterized by 1–2 m of organic-rich surficial strata, underlain by > 2 m of mineral-rich sand and silt beds that display a greater bulk density. Additionally, some cores contain deeper peaty strata intercalated within muds and sands. 14C dates of these buried peats range between 1910 and 3203 calendar years before present demonstrating that relatively old deltaic strata exist at shallow depths. Age comparisons of stratigraphically-similar peat beds from this study and previous delta-lobe chronological models indicate that the St. Bernard lobe prograded eastward at a time-averaged rate of 75 m/yr. From a geotechnical standpoint, the surficial, uncompacted (<2 m depth, average 1.15 g/cc bulk density) peaty strata in both basins are likely to erode and/or compact under the influence of diversion flows, but deeper consolidated mineral-rich strata (average 1.85 g/cc bulk density) are likely to be more resistant. Hydrodynamic models that predict the erosion associated with river-sediment diversion outflows in this region would benefit from incorporating a two-layer subsurface configuration, with a weaker, peat-like layer overlying a stronger, mineral-rich layer. The results of our study suggest that regions with an abundance of clastic strata at depth should be sought out when planning coastal restoration methods such as river-sediment diversions.

Coastal Land Loss in Louisiana: From Denial to Reality

Coastal Land Loss in Louisiana: From Denial to Reality

Economic Evaluation of Coastal Land Loss in Louisiana

Louisiana has lost approximately 1,880 square miles of land over the past eighty years. Projections suggest that in a future without action, the next fifty years could result in the loss of 1,750 additional square miles of land area. As land loss continues, a large portion of the natural and man-made capital stocks of coastal Louisiana will be at greater risk of damage, either from land loss or from the associated increase in storm damage. We estimate the replacement cost of capital stock directly at risk from land loss ranges from approximately $2.1 billion to $3.5 billion with economic activity at risk ranging from $2.4 billion to $3.1 billion in output. Increases in storm damage to capital stock range from $8.7 billion to as much as $133 billion with associated disruptions to economic activity ranging from an additional $1.9 billion to $23 billion in total lost output.

Challenges of ecosystem restoration in Louisiana – availability of sediment and its management

Abstract. Human intervention has impaired the Mississippi River’s ability to deliver sediment to its delta wetlands, and as a consequence acute land loss in coastal Louisiana has resulted in an unprecedented ecocatastrophe. To mitigate this degradation, an unparalleled restoration effort is underway. For this effort to be successful and sustainable, various sediment input mechanisms must be integrated, including: building appropriate sediment-diversions; beneficially using the millions of cubic metres of sediment dredged annually from navigational channels; harvesting deposits of sand and suitable sediment from the river and offshore; and related sediment management activities that are compatible with other uses of the river. A comprehensive sediment management plan has been developed to identify and delineate potential sediment sources for restoration, and to provide a framework for managing sediment resources wisely, cost effectively, and in a systematic manner. The Louisiana Sediment Management Plan provides regional strategies for improved comprehensive management of Louisiana's limited sediment resources.

Mitigating land loss in coastal Louisiana by controlled diversion of Mississippi River sand

The Bonnet Carre Spillway diverts floodwaters from the Mississippi River to Lake Pontchartrain, and was opened for 42 days during the 2011 flood. According to measurements of the newly deposited sediments, at least 31–46% of the river’s sand load was diverted into the spillway at this time, suggesting that such diversions can help mitigate coastal wetland loss.

David M. Burley: Losing ground: identity and land loss in coastal Louisiana

David M. Burley: Losing ground: identity and land loss in coastal Louisiana

Losing Ground: Identity and Land Loss in Coastal Louisiana. By David M. Burley. Jackson: University Press of Mississippi, 2010. xv + 166 pp. Illustrations, maps, notes, bibliography, and index. Cloth $40.00.

<i>Losing Ground: Identity and Land Loss in Coastal Louisiana</i>. By David M. Burley. Jackson: University Press of Mississippi, 2010. xv + 166 pp. Illustrations, maps, notes, bibliography, and index. Cloth $40.00.

Losing Ground: Identity and Land Loss in Coastal Louisiana - By David M. Burley

Losing Ground: Identity and Land Loss in Coastal Louisiana - By David M. Burley

Preventing land loss in coastal Louisiana: Estimates of WTP and WTA

A dichotomous-choice contingent-valuation survey was conducted in the State of Louisiana (USA) to estimate compensating surplus (CS) and equivalent surplus (ES) welfare measures for the prevention of future coastal wetland losses in Louisiana. Valuations were elicited using both willingness to pay (WTP) and willingness to accept compensation (WTA) payment vehicles. Mean CS (WTP) estimates based on a probit model using a Box–Cox specification on income was $825 per household annually, and mean ES (WTA) was estimated at $4444 per household annually. Regression results indicate that the major factors influencing support for land-loss prevention were income (positive, WTP model only), perceived hurricane protection benefits (positive), environmental and recreation protection (positive), distrust of government (negative), age (positive, WTA model only), and race (positive for whites).

The Multiple Lines of Defense Strategy to Sustain Coastal Louisiana

Abstract Coastal Louisiana has entered a period when the convergence of at least two powerful processes is working against its survival. Meteorological processes driving tropical systems have more frequently generated category 4 and 5 hurricanes and, although not a certainty, more destructive hurricanes are predicted for coming decades. Since the 1950s, the processes driving coastal land loss in Louisiana have continued only slightly abated. A deteriorating coast and historically inadequate levees make Louisiana acutely susceptible to the negative consequences of hurricane surge events. Coastal Louisiana's crisis of vulnerability is the continued temporal overlap of weakened hurricane protection with more frequent, intense hurricanes. The multiple lines of defense strategy proposes that two essential elements of the Louisiana coast be managed and perpetuated, which together can economically sustain the coast. The two planning elements are (1) using natural and manmade features (lines of defense) that dire...

Drawing Louisiana's new map: addressing land loss in coastal Louisiana

Drawing Louisiana's new map: addressing land loss in coastal Louisiana

Louisiana’s Wetlands: A Lesson in Nature Appreciation

Hurricane Katrina’s disastrous flooding of the Gulf Coast confirmed three decades of warnings by scientists. Most of New Orleans is below sea level, and South Louisiana’s coastal wetlands, which once helped buffer the city from giant storms, have been disappearing at a spectacularly swift pace. Now some researchers are calling for restoration of wetlands and barrier islands to help protect New Orleans the next time a hurricane strikes. An average of 34 square miles of South Louisiana land, mostly marsh, has disappeared each year for the past five decades, according to the U.S. Geological Survey (USGS). As much as 80% of the nation’s coastal wetland loss in this time occurred in Louisiana. From 1932 to 2000, the state lost 1,900 square miles of land to the Gulf of Mexico. By 2050, if nothing is done to stop this process, the state could lose another 700 square miles, and one-third of 1930s coastal Louisiana will have vanished. Importantly, New Orleans and surrounding areas will become ever more vulnerable to future storms. “New Orleans can’t be restored unless we also address coastal and wetland restoration too,” says Craig E. Colten, a geographer at Louisiana State University (LSU).

Nesting Habitat Requirements of the Brown Pelican and Their Management Implications

Because of the severe land loss in coastal Louisiana, many natural nesting areas for the Brown Pelican (Pelecanus occidentalis) are disappearing. Based on field measurements, geographical information system analysis, and a review of the relevant literature, we developed design criteria for the optimal artificial breeding habitat for Brown Pelican. Brown Pelican colonized islands had at least 70% open water within 20 km surrounding the island. Persistent pelican colonies occurred at least 7 km from the mainland and 0.3 km from the nearest island. Long-term colonized islands were between 10 and 70 ha in size with the shrub and dune habitat ranging from 2 to 20 ha on these islands. Pelicans preferred nesting in shrubs, and nesting occurred at an average elevation of 30 cm above mean sea level. We recommend that management for pelican nesting habitat includes loafing habitat: a beach that is at least 28 m wide is recommended.

Effect of Hydrologic Management on Marsh Surface Sediment Deposition in Coastal Louisiana

High rates of coastal land loss in Louisiana have prompted efforts to maintain or restore coastal wetland habitats, and structural management of marsh hydrology is one of a number of approaches that has been adopted. The aim of this study was to determine the effect of hydrologic management measures on marsh-surface sediment deposition in the Mississippi deltaic plain. Four impoundments, ranging in size from 50 ha to 177 ha and similarly sized control sites were included in the study. At each site, marsh-surface sediment traps were collected approximately biweekly for 3.5 yr to measure changes in sediment deposition. There was no significant difference in sediment deposition between any of the impoundment and control sites during the premanagement period. The results show no significant difference in marsh-surface sediment deposition between management year 1992–1993 and management year 1994–1995, but management year 1993–1994 had significantly lower sediment deposition than either the first or the last year of the study. Management year 1992–1993 showed the highest sediment deposition when it was assessed across all basins, areas, and sites, and this high rate of deposition is accounted for by the impact of Hurricane Andrew. For all management years there were significant differences between impoundment and control sites, with control sites showing higher rates of marsh surface sediment deposition than impoundments. No clear pattern was identified concerning the influence of various types of hydrologic management on rates of sediment deposition. This reduction in sediment deposition indicated that the areas under management in this study are receiving insufficient inorganic sediment deposition to keep pace with sea-level rise.

Salinity Trends in Louisiana Estuaries

If long-term trends in the character of the estuarine salinity field are contributing to land-loss in coastal Louisiana, then evidence of the presence of these trends may exist in historical salinity records. Nonparametric tests for the presence of a trend in the time series of various salinity statistics were performed. The results appear to be strongly influenced by climatological variations of decadal scale. Statistically significant trends were found at many stations. Both increasing and decreasing trends occurred with no apparent underlying spatial pattern. The observed changes during the time covered by the available records were generally too small to be lethal to the dominant marsh plants.