Coastal degradation has spurred active restoration of mangrove ecosystems, from local initiatives to global commitments to increase mangrove forest area by 20% over the next decade. Mangrove restoration projects typically have multiple objectives, including carbon storage, coastal resilience, and fisheries recovery. How planting seedlings, the most common form of active restoration, can promote recovery of mangrove ecosystem functions remains an urgent research need. We quantified multiple ecosystem outcomes of Guyana's national mangrove restoration program, approximately a decade after seedling planting, and compared restoration outcomes with conditions in intact and degraded mangrove forests. Multivariate analyses indicate that intact and restored sites' environmental conditions were similar to each other but different from degraded sites. Aboveground biomass in restored sites (103 Mg ha −1 ) was 13 and 99% greater than intact (89.4 Mg ha −1 ) and degraded (0.12 Mg ha −1 ) sites, respectively. Active restoration successfully increased seedling abundance of both planted and unplanted species, with similar abundance between intact and restored sites. In contrast, fish communities in restored sites remained similar to degraded sites. Restored sites were dominated by a single algivorous fish species, with lower species diversity and commercially valuable fisheries than intact sites. Our results demonstrate that active restoration is a viable option to restore mangrove forest tree biomass and tree species composition in this region. However, even under a best-case scenario for mangrove forest restoration, fisheries did not recover during our study's timespan. Long-term monitoring and controlled experiments will be essential to further understand restoration outcomes for multiple ecosystem services in mangrove forests.

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Climate change is impacting people and their environment at an ever-growing rate. Underdeveloped countries like Guyana, which are heavily dependent on agriculture for sustenance are most vulnerable to the effects of climate change compared to developed countries. Globally, climate change negatively impacts agriculture with serious implications for livelihoods. For this study, 114 semistructured interviews were conducted in 18 villages on the Essequibo Coast, Guyana, where agriculture is the major economic activity. Climate data (temperature and rainfall) were obtained for the past three decades from the Hydrometerological Office, Guyana. We found that temperature has been increasing over the last three decades. Rainfall patterns were observed to be fluctuating with a general increase over time. A majority of the farmers experienced the effects of climate change but they were also unaware as to why these were occurring. Most farmers were affected by floods, which is becoming much more prevalent as a result of climate change. This resulted in major crop losses and had high financial impacts on farmers. Farmers have been using various methods to adapt to the changes. In the past, farmers used leaves and bushes to get rid of pests and diseases. Presently, farmers were using more chemicals and fertilizers. It is recommended that emphasis be placed on awareness to better equip farmers to cope with climate change challenges. This study complemented similar studies from different regions of Guyana and globally to offer resources to farmers and policy-makers on strategies for climate change impact and mitigation in farming.

Agriculture is the most important economic activity around the world with its contributions reflected by its share in the gross domestic product of countries. It ensures food security, provides raw materials for many industries and employment opportunities. Today, pest and diseases are among the main challenges plaguing the agricultural sector. More specifically, phytophagous mites are devastating many economically important crops worldwide. Tetranychus urticae Koch (Two-spotted spider mites), Raoiella indica Hirst, (red palm mites), Polyphagotarsonemus latus Banks (broad mites) and Panonychus ulmi Koch (European red mites) are widely known for their extensive damage to crops. To control these mites, farmers have incorporated the use of pesticides into their farming systems. However, chemical control comes with many problems such as insect resistance, detrimental environmental effects and various human health implications. As such biological control is an environmentally friendly alternative that uses bio-control agents such as predators, pathogens and parasitoids to control pests. In this review, it was found that predators and pathogens were the most widely used biocontrol agents, specifically, the Amblyseius spp. Berlese were most effective and widely documented. The available literature also suggests that for successful control of agricultural mites via biological control, there needs to be a clear understanding of the behaviors of these mites and the bio-control agents used.

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Abstract. Prashad L, Daniel R, Ram M. 2020. Survey of the bacterial diversity at two coastal beaches in Guyana. Biofarmasi J Nat Prod Biochem 18: 1-8. The #63 Beach, Berbice and Marriott Beach, Kingston Seawall, Guyana were surveyed for halophilic bacteria present in its waters. NaCl tolerance, temperature tolerance and antimicrobial activity of isolates against Staphylococcus aureus and Bacillus sp. were tested. Samples of 100 mL were taken from the Shore, 5.0 m, and 10.0 m depth from both locations. The samples were plated and examined for the growth of bacteria of different pigmentation. A total of 4 halophilic isolates were found; 3 from Marriott Beach (Isolates A, B, and G) and 1 (Isolate M) from the #63 Beach. Isolates were of yellow, light orange and pink pigmentation, the 3 isolates from Marriott Beach were, Gram-negative and cocci while the one isolates from #63 Beach were Gram-positive and cocci. The optimum salinity tolerance for the Isolate G from Marriott Beach was 1.5M NaCl, Isolate M from #63 Beach 1.0M NaCl, Isolate B from Marriott Beach 1.0M NaCl and Isolate A from, Marriott Beach 0.5M NaCl. The optimum temperature for the growth of the isolates was 37°C. The isolates had no antimicrobial activity against S. aureus and Bacillus sp.

Abstract. Matto AA, Jaikishun S, Ram M. 2023. Impacts of different salinity levels on seedling growth and survival of black mangrove (Avicennia germinans). Asian J For 7: 67-73. Mangroves are important for coastal protection and provide numerous ecosystem services such as breeding, feeding, and nursery grounds for commercial fishes. This research examined the survivability of black mangrove (Avicennia germinans (L.) L.) seedlings in seven salinity concentrations. Growth parameters were collected every ten days, and a post-harvest analysis was done at the end of the data collection period. The results indicated that as the salinity level increased, the growth of the seedlings was reduced. Salinity can affect the different parameters collected in the growth of young seedlings. In the control, which was given zero salinity (0 ppt), it was noted that the growth parameters were not significantly affected. The lower treatments, such as T2 (15 ppt), 3 (30 ppt), and 4 (45 ppt), indicated that the seedlings strive better in these conditions. In treatment 7, which was the highest salinity level (90 ppt), the growth parameters of the seedlings were reduced. The findings of this research indicated that black mangrove seedlings need a low salinity level to have a good growth establishment. Given the adaptability of A. germinans, these mangrove species are anticipated to be flexible to cope with a wide range of future climatic circumstances.

This study compared the antibacterial activity of honey-garlic and honey-ginger mixtures against two clinically important bacteria frequently implicated in acute wound infections; Pseudomonas aeruginosa and Klebsiella pneumoniae. Individual extracts of honey, ginger, garlic and erythromycin antibiotics (positive control), were also tested. Concentrations of 100%, 75%, 50%, and 25% of the natural extracts and mixtures were prepared by the use of sterilized distilled water as the solvent. The antibacterial activity of each natural extract and the antibiotic was tested against the aforementioned bacterial species at different concentrations using the disc diffusion method. Further, MIC and MBC tests were conducted on each natural mixture using the broth dilution method and spread plate method, respectively. Our results showed garlic exhibited the highest antibacterial activity against both bacteria at 100% concentration, whereas honey and ginger showed the lowest antibacterial activity against Klebsiella pneumoniae and Pseudomonas aeruginosa, respectively at 25% concentrations. Honey-garlic mixture was the most effective against Klebsiella pneumoniae, whereas honey-ginger mixture was the most effective against Pseudomonas aeruginosa. The antibiotic was more effective than the natural mixtures against Pseudomonas aeruginosa, but not so effective against Klebsiella pneumoniae. The MIC of both mixtures against Pseudomonas aeruginosa ranged from 25%-50%, while it ranged from 6%-50% for Klebsiella pneumoniae. Honey-garlic was the only mixture against Klebsiella pneumoniae that exhibited bactericidal effects at 50% (MBC).