Papers by Chetwynd Osborne
Peatlands are found on all continents, covering 3% of the global land area. However, the spatial ... more Peatlands are found on all continents, covering 3% of the global land area. However, the spatial extent and causes of metal enrichment in peatlands is understudied and no attempt has been made to evaluate global patterns of metal enrichment in bog and fen peatlands, despite that certain metals and rare earth elements (REE) arise from anthropogenic sources. We analyzed 368 peat cores sampled in 16 countries across five continents and measured metal and other element concentrations at three depths down to 70 cm as well as estimated cumulative atmospheric S deposition (1850–2009) for each site. Sites were assigned to one of three distinct broadly recognized peatland categories (bog, poor fen, and intermediate-to-moderately rich fen) that varied primarily along a pH gradient. Metal concentrations differed among peatland types, with intermediate-to-moderately rich fens demonstrating the highest concentrations of most metals. Median enrichment factors (EFs; a metric comparing natural and ...
Journal of Academic Research & Essays, 2022
Moringa oleifera is characterised as an effective alternative to traditional approaches for the t... more Moringa oleifera is characterised as an effective alternative to traditional approaches for the treatment of gold mine tailings spoils, particularly for its low cost, non-toxic nature, and simple application. This study investigated the use of M. oleifera seed powder as a primary coagulant for the treatment of gold mine tailings with respect to turbidity reduction, and the effect of varying pH on the coagulation process. The tailings sample used in the study was collected from an active mining operation in the Waiamu area, Cuyuni Mining District 4, Guyana; with the average turbidity ranging between 216.33 ± 4.62 and 275.33 ± 8.33 NTU. The standard jar test procedure was used to assess the efficiency of the M. oleifera coagulant based on measurements of turbidity reduction. M. oleifera was found to be an effective coagulant for reducing turbidity in the selected gold mine tailing pond, with the best turbidity reduction being 91.31 ± 0.53%. Further evidence from the study suggested that at the optimum coagulant concentration of 250mg/L, turbidity reduction changed as pH levels (5, 6, 7, 8, 9) were altered, whereby reduction at the natural pH level of 7 (control) was 91.31 ± 0.53%; and following adjustments of pH levels to 5, 6, 8 and 9, turbidity was reduced by 85.00 ± 0.58%, 84.88 ± 0.94%, 77.81 ± 5.21% and 74.16 ± 5.28% respectively. Therefore, strong knowledge of biological approaches for the treatment of gold mine tailings spoils would be pivotal to support long-term decisions on wastes management and disposal.
International Journal of Multidisciplinary Research and Growth Evaluation, 2022
Rice (Oryza sativa) farming is a key economic activity in Guyana that has been progressively incr... more Rice (Oryza sativa) farming is a key economic activity in Guyana that has been progressively increasing over the years in terms of production and export. However, yields are often reduced by pest attacks during different stages of development of the rice plant. Additionally, the desired outcome of controlling pests in an environmentally-friendly manner is not easily achieved. This study investigated the effectiveness of four plant leaf extracts at different concentrations against the golden apple snail (Pomacea sp.). Mortality rates over a four-day period were compared with those obtained for traditional chemical control. Two of the four extracts were found to be as effective as the chemical control and are therefore recommended for future consideration as alternative pest control.
Journal of Academic Research & Essays, 2021
International Journal of Scientific Research in Biological Sciences, 2021
Areas across South-Central Guyana are very diverse and have the potential to sustain freshwater g... more Areas across South-Central Guyana are very diverse and have the potential to sustain freshwater groups of vertebrates and invertebrates even though these areas are prone to major gold mining activities which have major impacts on the biodiversity both on land and in water. Some of the areas surveyed comprised of water bodies that were fully mined out and groups such as fishes, amphibians, insects, mollusks and crustaceans were the most representative animals.
The knowledge of freshwater shrimps and crabs from Guyana is poor; hence the importance of this survey to identify the physicochemical parameters that serve as the best predictors of the density of crab and shrimps and examine the diversity trends using taxa abundance of crabs and shrimps.
Water temperature (℃) and dissolved oxygen (mg/l) seemed to be the best physicochemical parameters as it relates to predicting crustacean density and distribution across sites. River locality sites seem to have a stronger effect on crustacean community structure as compared to other surveyed localities (creek and waterfall), possibly indicating more suitable conditions within these sites. The number of five species of shrimps and four species of crabs was normal if we consider the range of area sampled.
Data captured for my research that explored the Relationship between Mangroves Resiliency and Fis... more Data captured for my research that explored the Relationship between Mangroves Resiliency and Fish Populations in the Largest Marine Reserve in Belize: A Case for Conservation. Data shows forest structure (mangrove species, DBH and height measurements, prop root measurements, density, standing biomass, basal area, and vulnerability ranking) and fish population (biomass, size, density, and abundance). Data was also prepared in text file format for analysis using the R Software. R Codes are provided also.
Mangrove forests are one of the most bio-diverse and productive wetland environments on earth. Ho... more Mangrove forests are one of the most bio-diverse and productive wetland environments on earth. However, these unique tropical forest environments that occupy coastal areas are among the most threatened habitats globally. Approximately one-third of the world's mangrove forests in tropical and subtropical coastlines have been lost to logging, conversion of land for agriculture and mariculture, and degradation due to general pollution over the past 50 years. The large population of mangroves occupying the Turneffe Atoll area in Belize face growing anthropogenic threats such as permanent clearing of land for housing and infrastructural development as well as pollution and natural factors (climate change). Despite these threats, mangroves have high resilience due to their fast rates of microbial decomposition and nutrient flux, large storage of nutrients below-ground, numerous feedbacks, keystone species redundancy and self-design, and highly efficient biotic controls. Given the few formal studies done to evaluate mangrove resilience at Turneffe Atoll, the purpose of this study was to evaluate mangrove resilience and nursery functions in the Turneffe Atoll Marine Reserve. Mangrove fish abundance, forest structure, and prop root length was assessed by means of visual census and point centred quarter method (PCQM) for 11 sites that span across conservation and general use zones. This study found that resilient mangroves (lower vulnerability ranks, higher standing biomass, and higher fish biomass and abundance) exist in conservation and general use zones and warrant the need for improved mangrove conservation measures. Some conservation measures include: greater reduction of non-climate stressors, establishment of more mangrove conservation areas, and implementation of more outreach and educational programmes. .
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Papers by Chetwynd Osborne
The knowledge of freshwater shrimps and crabs from Guyana is poor; hence the importance of this survey to identify the physicochemical parameters that serve as the best predictors of the density of crab and shrimps and examine the diversity trends using taxa abundance of crabs and shrimps.
Water temperature (℃) and dissolved oxygen (mg/l) seemed to be the best physicochemical parameters as it relates to predicting crustacean density and distribution across sites. River locality sites seem to have a stronger effect on crustacean community structure as compared to other surveyed localities (creek and waterfall), possibly indicating more suitable conditions within these sites. The number of five species of shrimps and four species of crabs was normal if we consider the range of area sampled.
The knowledge of freshwater shrimps and crabs from Guyana is poor; hence the importance of this survey to identify the physicochemical parameters that serve as the best predictors of the density of crab and shrimps and examine the diversity trends using taxa abundance of crabs and shrimps.
Water temperature (℃) and dissolved oxygen (mg/l) seemed to be the best physicochemical parameters as it relates to predicting crustacean density and distribution across sites. River locality sites seem to have a stronger effect on crustacean community structure as compared to other surveyed localities (creek and waterfall), possibly indicating more suitable conditions within these sites. The number of five species of shrimps and four species of crabs was normal if we consider the range of area sampled.