Guyana Coast Research Articles

Characterization of small-scale net fisheries off the coast of Guyana

Characterization of small-scale net fisheries off the coast of Guyana

Tracking the long‐term vegetation and soil characteristics of restored mangroves: a case study from Guyana's coast

The global urgency to halt and reverse mangrove loss has led to the implementation of numerous initiatives to protect and restore mangroves and recover critical ecological functions and services. Restoration success is assessed by estimating mangrove survival, while diversity, vegetation structure, and soil characteristics are often overlooked with no long‐term monitoring. Here, we investigated long‐term changes in vegetation and soil characteristics of Avicennia germinans‐dominated stands planted along Guyana's coast between 5 and 11 years old. A chronosequence approach was used to examine changes in vegetation and soil parameters in restored mangrove stands of different ages compared to natural stands of the same ages. Tree height, diameter, and aboveground biomass were inconsistent between restored and natural mangrove stands. Redundancy analysis (RDA) revealed that the soil properties were the important factors influencing both the restored and natural mangrove communities. There were no clear trajectories between the vegetation and soil characteristics with age, possibly due to site‐specific and hydrodynamic environmental factors, such as tidal dynamics, riverine inputs, and climatic variations. While there were some equivalent vegetation and soil characteristics at the end of the first decade after restoration, the restored mangroves may require a longer timespan (approximately 25 years) than the period overserved in our study to be entirely identical to the natural mangroves. This case study from Guyana provides valuable insights into the ecological processes driving mangrove recovery dynamics, growth patterns, and restoration effectiveness and offers reliable data needed to inform future restoration projects.

River mouth morphodynamics and deflection over the short term: effects on spit growth and mangrove dynamics

The river mouth shows the influence of the dynamics of sediment deposition and the processes organising the deposits. The river mouths of the Guyana coast, as with other coastal systems in the Guianas, are influenced by the deposition of mud banks from the Amazon River and other rivers. This study analysed and probed the influence of the riverine and marine influences on small river mouth morphological developments. In this study, the morphological dynamics of the system were carried out from satellite images through the comparison of the inter-annual morphodynamics of the river mouths, complemented by data from hydrodynamic processes among others. This study demonstrates that the recent advancement and availability of Synthetic Aperture Radar (SAR), remotely sensed data, allow for the classification of migrating river mouth action and processes; effective monitoring of mudflats development and spit formation; and, the exhibition of river mouth transitioning and infilling. Sentinel-1 images of the Mahaica-Mahaicony river mouth in Guyana were processed and analysed using Google Earth Engine (GEE) and ArcGIS to observe the mud dynamics and its effects on deflecting the river mouth, influencing the development of spit and mangrove dynamics. The results of the analyses show that the dynamics of the mud shoal and river mouth are governed by feedback from various estuarine and hydrodynamic processes resulting from the interactions between the river and ocean. The results have not only highlighted the importance of mud infilling and sediment build-up for spit development and river-mouth deflection but the impact of the sediment morphological dynamics on the ecosystem (mangrove) associated with the river mouth.

From the forest to the coast: the wild meat trade chain on the Coast of Guyana

In the Caribbean region, very little is known about wild meat use and trade. To contribute to this knowledge gap, we studied the wild meat trade chain on the coastal area of Guyana, which geographically and culturally connects the Caribbean and the Amazon Region. In Guyana, the wildmeat sector is legal and in the process of being regulated. Our study shows that the market chain on the coast of Guyana is a short and direct market chain where the harvester most often sells directly to the consumer or through one level of intermediary (market vendors, home-based traders, roadside traders, restaurants, food stalls or rum shops). In coastal Guyana, wild meat can be considered a luxury, rather than a necessity: the price is higher compared to other alternative sources of meat and demand rises for special events. The topmost sold species are Cuniculus paca, Mazama americana, Tapirus terrestris, Dicotyles tajacu, Tayassu pecari, and Hydrochoerus hydrochaeris. The volumes traded to the coast of Guyana are equivalent to 361 tons of wild meat sold per year. Considering the population size on the coast of Guyana, this amount is equivalent to 1,4 g/capita/day and 4% of the protein intake from animal origin. These values are below those observed in urban towns from Central Amazonia in Brazil where wild meat consumption per capita equals to 18 g/capita/day. From a one health perspective, further attention is required with regards to food safety aspects along this legal trade chain.

Occurrence and characteristics of microdebris in commercial fish species of Guyana, South America

Microdebris ingestion in fish is widespread and has adverse effects on marine life. This study assessed the occurrence and type of microdebris found in three commercially important fish species from different landing sites along Guyana's coast. Visual examination of fish gut content was initially carried out using the naked eye and a hand lens. Microscopic examinations were subsequently carried out to determine the number and type of debris present. Forty percent of the fishes examined had microdebris present in their bodies. A total of 112 microdebris particles were collected from 90 specimens of three species (Bagre bagre, Nebris microps, Macrodon ancyclodon). The microdebris particles observed included pellets, microbeads, fragments, fiber (wool), films, and foams. White-colored materials were the most frequently ingested. Most of the collected materials were large microdebris (>1 to 5 mm) that resembled pellets and microbeads. This study displayed the prevalence of microdebris ingestion by commercial fish in Guyana.

Distribution and Abundance of Crabs in Restored and Natural Mangrove Forests along Guyana's Coast

his study investigated the viability of mangrove restoration as a tool to restore ecosystem services measured by the emergence of an important taxon, crabs. We compared crab abundance and diversity in natural and restored mangrove forests and the influence of biophysical parameters on their abundance.

The need for data integration to address the challenges of climate change on the Guyana coast

Guyana's capacity to address the impacts of climate change on its coastal environment requires the ability to monitor, quantify and understand coastal change over short-, medium- and long- term. Understanding the drivers of change in coastal and marine environment can be achieved through the accurate measurement and critical analyses of morphologies, flows, processes and responses. This manuscript presents a strategy developed to create a central resource, database and web-based platform to integrate data and information on the drivers and the changes within Guyana coastal and marine environment. The strategy involves four complimentary work packages including data collection, development of a platform for data integration, application of the data for coastal change analyses and consultation with stakeholders. The last aims to assess the role of the integrated data systems to support strategic governance and sustainable decision-making. It is hoped that the output of this strategy would support the country's climate-focused agencies, organisations, decision-makers, and researchers in their tasks and endeavours.

A Spatial Examination of Possible Land Use Implications from the Siting of a Petroleum Refinery on Guyana's Coast

Land use problems persist along Guyana’s densely populated coast, and since 2015 the rapidly growing oil and gas sector has intensified urban challenges. Given the potential for further development to process and store extracted petroleum resources, this study aimed to highlight the value of spatial analysis for supporting land use planning for the potential siting of a petroleum refinery. The study considered several criteria that may influence refinery placement, including land cover type, size, and distances from built areas, protected areas, mangrove stands, and transportation routes.

Knowledge, Treatment-Seeking, and Socioeconomic Impact of Malaria on the Essequibo Coast of Guyana

The study was conducted to provide insight into malaria control efforts in Guyana, and to identify areas to emphasize in future educational campaigns. To do this, a community-based survey of knowledge, treatment-seeking patterns, and socio-economic impact of malaria was conducted at four outdoor markets in Region 2 Guyana. One hundred and eight individuals between the ages of 16 and 65 who had a malaria infection in the previous twelve months were interviewed. Within the study population, 94% identified mosquitoes as being the source of malaria infection. More than 70% of respondents identified fever, headache and chills as symptoms of malaria. Sixty percent of individuals incorrectly believed that women could not be treated with antimalarials when pregnant or they risked spontaneous abortion or congenital defects. Most individuals (76%) used bed nets although very few nets were chemically treated. Mean delay in presentation to a health clinic was 6.3 days. Use of the official health care sector was high (96%) and relatively few individuals (15%) self-treated with antimalarials. Compliance with antimalarial regimens was also found to be relatively good (92%). Cost of treatment was significantly higher among those who used private clinics (US$ 13.74) than those who used public clinics (US$ 0.96) (p < 0.001). The good level of knowledge of malaria may be due to the relatively high literacy rate and level of education in Guyana. The fact that public clinics in Guyana provide treatment and antimalarials at no cost may explain the relatively high use of the official health sector, low levels of self-treatment, and good compliance.

Antifungal Activity and Phytochemical Screening of Cymbopogon citratus, Cajanus cajan and Plectranthus amboinicus Leaves Collected in Guyana, South America

Aims: Medicinal plants have been a fundamental part of the human health since existence. Guyana is surrounded high in the green shoulder of northern South America and shares Amazon River and Amazon Forest. South American population use plant extracts obtained from traditional medicinal plants as treatment for many infectious diseases. The study aimed to estimate antifungal property and chemical composition of the three medicinal plants Cymbopogon citratus (lemongrass), Cajanus cajan (pigeon pea) and Plectranthus amboinicus (thick leaf thyme) leaves collected from the coastal areas of Guyana.
 Study Design: Experiment based study.
 Place and Duration of Study: Plants were gathered along the East Coast of Guyana and identified at the Biodiversity Center, University of Guyana, Georgetown, Guyana between January 2017- May 2017.
 Methodology: Phytochemical extraction was conducted using the soxhlet and rotovap apparatus and an aqueous extraction method. Data analysis of the study was done using R-Studio Program for statistical computing and graphics. A Tukey test was done along with ANOVA and Boxplots.
 Results: Qualitative analysis of phytochemicals was carried out and the presence of terpenoids, steroids, glycoside, alkaloid, tannins and saponins were positive in some plants. Antifungal activity was tested using the poisoned food and well diffusion techniques.
 Conclusion: In conclusion, C. cajan showed significant zones of inhibition using a well diffusion technique whereas hexane extract showed significant inhibition with poisoned food technique.

Numerical simulation of a passive heave compensator for scientific research ships

Research vessels are commonly used on a daily basis for ocean exploration and payload handling. However, due to unpredictable wave motion on the ship and the flexibility of the cable, the heave of the ship is unavoidable and causes danger during operations, loss of payload, possible damages to expensive equipment and prolong period of downtime. A compensator system is an essential part of operations to mitigate this effect and to ensure safety, reduce down-time of operation and increase efficiency while providing longer and better duration of operation even in harsh conditions. In this article, a passive heave compensator system with cylinder, accumulator and depth compensator connected in series by pressured pipes developed for a scientific research ship with length of 68m and breath of 16m is analyzed along the coast of Guyana, South America. The payload used in this analysis is 200 ton. The working principle of the heave compensation system is described, the parameters affecting the performance of the system are simulated and analyzed using MatLab. A 3D model of the system is built using SolidWorks and schematic drawings are produced from AutoCAD. The compensation rate of the system is higher than 77% under the influence of the input wave and the system has a response of an average setting time of 18s. The point of maximum load exerted is at the splash zone. For a typical most probable extreme significant wave height, Hs= 2.3m, period T= 6s and direction μ= 45° in the operational area, the reduction in heave motion when the vessel is equipped with the heave compensator is approximately 77% compared to 47% reduction when the vessel is without a compensator.

Shoreline change identification and analysis along the coast of Guyana, South America

Guyana's coast is one of those in South America subjected to shoreline change. Understanding of spatio-temporal changes in shoreline position and the processes that drive the changes is very important in coastal protection, for increased shoreline surveillance and future planning. The aim of this study was to investigate the spatial and areal extent of this shoreline's morphological dynamics. It examined 49 years of the spatio-temporal behaviour of Guyana's shoreline by integrating and analysing the historical georeferenced satellite images in Google Earth repository, from 1969 to 2015 and onsite field mapping undertaken in 2017-2018. These were analysed using the Digital Shoreline Analysis System (DSAS) package of USGS in ESRI's© ArcGIS software. Rates of shoreline change were evaluated for the entire shoreline and these rates of change results varied at different sections of the entire coastline. Most of the Guyana coastal area continued to face shoreline erosion. The driving forces of the change were attributed to the natural forcing (sea level rise) and anthropogenic factors (e.g., sand mining and progressive depletion of mangrove forests). Anthropogenic interventions, such as the construction of breakwaters and mangrove rehabilitation and replanting were noticed to be responsible for some region-specific positive responses and adjustment to shoreline behaviour.

Shoreline change identification and analysis along the coast of Guyana, South America

Shoreline change identification and analysis along the coast of Guyana, South America

Regaining Jerusalem: Eschatology and Slavery in Jewish Colonization in Seventeeth-Century Suriname

Through the person of the ex-converso David Nassy, “Regaining Jerusalem” asks how seventeenth-century Portuguese Jews could seek their own religious liberty at the same time they were enslaving Africans in the plantation economies of the Caribbean and the Guyana coast. Living in Amsterdam by the 1630s, Nassy was part of the Jewish community in Dutch Brazil, and then in the 1660s led the Jewish settlement in Dutch Suriname. Nassy was moved in part by eschatological hopes shared with other ex-conversos freed from Catholic tyranny, in part by his interest in plants and geography, and in part by entrepreneurial desire for profit. Nassy and his fellow Jews distinguished their own biblical exodus out of slavery from the destiny of their African captives, incorporating their slaves into the patriarchal Abrahamic household. This paper describes patterns of Jewish culture on the sugar plantations and the varied reactions of African men and women to it.

Taxonomy of Earthworm Species Collected from East Coast of Guyana

Taxonomy of Earthworm Species Collected from East Coast of Guyana

Coastal engineering and large-scale mangrove destruction in Guyana, South America: Averting an environmental catastrophe in the making

This short communication highlights potential destabilisation of the muddy coast of Guyana, South America, caused by large-scale mangrove destruction. The stability of the coast of Guyana, which is part of one of the world's most extensive mangrove coasts, depends on large mud banks migrating alongshore from the mouth of the Amazon River and on mangrove colonisation of these banks. Under the pressures of economic development, the coastal zone of Guyana is progressively being transformed into agricultural land and aquaculture estates, protected by coastal dikes. These hard coastal defence structures, constructed in recent years, are less effective in dissipating wave energy than mud banks. They also hinder the various processes involved in the consolidation and subsequent mangrove colonisation of these banks, notably by enclosing mature mangrove forests and preventing propagule transport from these forests to mud banks. If unchecked, the progressive breakdown in the mud-bank and associated mangrove system that has led to progradation of the coastal plain of Guyana over the last 5000 years will result in large-scale coastal erosion that can only be countered by further engineering structures at prohibitive costs. The only coastal defence strategy, sound and viable over the long term, with regards to both environmental conservation and cost, consists in restoring a dynamic mud-bank and mangrove system on this wave-exposed coast.

GIS-Based Analysis and Modeling of Coastline Advance and Retreat Along the Coast of Guyana

This research utilized a Geographical Information System (GIS)-based approach to analyze, map and model coastline advance and retreat. A time series (1941–1987) of empirical advance and retreat data from the coast of Guyana was used. Coastlines were also extracted from 1987, 1990 and 1992 Landsat TM images, and 1999, 2002, 2004 and 2006 Landsat ETM+ images. The historical data were used to calculate advance and retreat (AOR) rates and sediment volume changes. Distinct periods of advance and retreat matched corresponding periods of sediment gains and losses. The Digital Shoreline Analysis System (DSAS) was used to predict rates of coastline change. Graphical plots of DSAS results identified spatial and temporal phase shifts of the coastline. Recurring episodes of accretion and erosion could be associated with the presence or absence of mudbanks along the coast.

Time-Series Modeling of Data on Coastline Advance and Retreat

Abstract An empirical time series (1941–2007) of advance and retreat data from the coast of Guyana is modeled with statistical time-series techniques. Subseries of 5-y periods are fitted to modified Box-Jenkins space–time models. Second-order spatial-cyclic autoregressive models, associated with cyclical advance and retreat patterns, fit the data for five different subseries. First-order autoregressive models are also suitable to describe the data from five other subseries, thereby suggesting a long-memory response in the coastal system. Three of the subseries are fitted to space–time autoregressive moving-average models, thereby indicating the presence of random shocks (i.e., random events) in the coastal system. The various models are indicative of cyclical, long-memory, and short-memory processes operating in the coastal system. These processes can be associated with mudshoal propagation and stabilization and with temporal stochastic processes that force the coast to advance or retreat in different loc...

Willingness to pay for water on the Guyana east coast

Improvements in the water supply and wastewater sectors in Guyana are recognised as being critical to poverty reduction and sustainable economic growth. Such improvements, however, cannot be effected without the water utility companies maximising cost recovery which requires a high level of willingness to pay on the part of consumers. This research was carried out on the east coast of Guyana to establish households' willingness to pay for water supply improvements. A questionnaire was used to collect data on several socio-economic variables, water supply status, utility payment preferences and willingness to pay. Using probit statistical techniques, willingness-to-pay values were estimated. The results of this study are consistent with others, that show that household income, level of education, employment status of the head of the household and level of consumers' awareness are the principal factors influencing willingness to pay for services. The results also show that the demand is inelastic and that the numerical value of price elasticity (−0·85) is close to one which may be due to the current wide use of the rainwater harvesting substitute. It is recommended that Guyana Water Incorporated consider the results of this study in its policy formulation for improving its services.

Late Pleistocene palaeoproductivity patterns during the last climatic cycle in the Guyana Basin as revealed by calcareous nannoplankton

Variations in the assemblage and abundance of coccoliths reveal changes in oceanic and atmospheric dy- namics in the Guyana Basin over the last climatic cycle, mainly linked to latitudinal variations in the ITCZ (Intertrop- ical Convergence Zone). Records of the N ratio (a palaeo- productivity index of coccolithophores) allowed us to mon- itor nutri-thermocline fluctuations. Nannofossil accumula- tion rates (NAR) vary closely with the N ratio, indicating a strong correlation between these two palaeoproductivity proxies. Decreases in the N ratio and NAR values sug- gest lower palaeoproductivity during glacial substages, in- dicating a deep nutri-thermocline (deep stratification of the mixed layer) as a consequence of the piling up of warm water dragged by the NEC. This setting was favoured by the south- ern shift of the ITCZ and Trade winds which blew perpendic- ular to the Guyana coast. By contrast, increases in the N ra- tio and NAR values revealed higher palaeoproductivity dur- ing interglacial substages, suggesting a shoaling of the nutri- thermocline. This scenario is favoured by a northward dis- placement of the ITCZ with the southeast Trade winds blow- ing alongshore. Additionally, palaeoproductivity changes during substages of Marine Isotope Stage (MIS) 6-5 are of much higher amplitude than those recorded in substages of MIS 4-2 and the early Holocene. Similarities between the palaeoproductivity and the 65 N summer insolation records, suggest a link between the depth of nutri-thermocline, the lat- itudinal migration of the ITCZ and ice-sheet changes in the Northern Hemisphere.