Black Carbon - A Silent Contributor to Climate Change

Black carbon is a potent climate-warming component of particulate matter formed by the incomplete combustion of fossil-fuels, wood and other fuels. Complete combustion would turn all the carbon in the fuel into carbon dioxide, but combustion is never complete, and CO2, CO, volatile organic compounds, organic compounds, and black carbon particles are formed in the process. It contributes to warming by converting incoming solar radiation to heat. When deposited on ice and snow, BC and co-emitted particles reduce surface albedo thereby melting the glaciers. The complex mixture of particulate matter resulting from incomplete combustion is referred as soot. When suspended in the atmosphere, black carbon contributes to warming by converting incoming solar radiations to heat. It also influences cloud formation and impacts regional circulation and rainfall pattern. The Artic and the glaciated regions such as Himalayas are particularly vulnerable to melting as a result. The present paper aims to review the work done on black carbon and its mitigation measure.

Selected Metal Contents and Phytochemical Profiling of Ficus capreifolia and Mangifera indica Commonly used Antidiabetic Plants from Oil Producing Region of Nigeria

Aim: The study evaluated selected metal contents and phytochemicals present in Ficus capreifolia and Mangifera indica extracts commonly used antidiabetic plants from Aluu and Bodo communities in Rivers State, Nigeria. Place and Duration of Study: University of Port-Harcourt, Choba, Rivers State, Nigeria and its environs was used between June to November, 2020. Methodology: Composite soil samples and the leaves of Ficus capreifolia and Mangifera indica were collected from Bodo and Aluu communities respectively. Atomic absorption spectrophotometer was employed for the analysis of the metals (Zn, Pb, Ni, Mn, Fe, Cu, As and Cr). The plant extracts were screened for the presence of various phytochemicals using spectrophotometric methods. Results: Flavonoid, Saponins, Tannins, Alkaloids. Terpenoid, Glycoside and Carotenoid were detected in Ficus carpreifolia obtained from Bodo and Aluu communities while Magnifera indica obtained from both communities has Alkaloids, Phenols, Flavonoids, Saponins and Tannins detected. Metals such as Zn, Pb, Mn, Fe and As were detected at Bodo and Aluu soil samples. Cu, Ni and Cr were below the detectable limit. Zn, Pb and As were above the permissible limit in Bodo soil samples while only As was above the permissible limit in Aluu community. In the plant samples, only Mn was present and was within the permissible limit in plants samples obtained from Bodo and Aluu communities while Zn, Pb, Ni, Fe, Cu, As and Cr were below the detectable limit. Conclusion: The study shows that Ficus capriefolia and Mangifera indica do not bioaccumulate Fe, Zn, Ni, Pb, As and Cr and this may be attributed to the metal intolerance potential of the plants, hence no fear of metal toxicity when using these plants for medicinal purposes. The presence of saponins, tannins and flavonoid affirmed the hypoglycemic potentials of the plants.

Pesticide Use in Bangladesh: A Review on Potential Impacts

Bangladesh is a densely populated agricultural country. A wide range of products of pesticides being used in Bangladesh is already considered a health and environmental concern by different international agencies including the World Health Organization (WHO). Excessive, irrational use of pesticides in agriculture, and lack of knowledge on pest management have caused widespread pesticide pollution which is now posing a substantial threat to the environment and local people. In this review, we assessed and analyzed previous literature systematically to map a complete scenario of pesticide pollution in Bangladesh, covering soil, water, and foods. Most of the previous studies indicated that soil, water, and different seasonal vegetables are contaminated with organophosphorus, pyrethroid, and exceeded the FAO/WHO maximum residual limits. Concentration of chlorpyriphos, malathion were found below the detection limit in soil samples. But water samples were found contaminated with chlorpyrifos, diazinon, malathion, carbaryl and carbofuran. Considered vegetable samples were adulterated with fenvalerate, quinalphos, cypermethrin, fenitrothion, dimethoate, parathion, linuron, phenthoate. Persistence of organochlorines in the environment is limited and meets the maximum residue level (MRLs). This study will help to depict the pesticide pollution status in the environmental matrices in recent years and to cut off the exacerbation of pesticide pollution. A proactive approach is essential to limit the pesticide pollution load in the environmental matrices.

Study and Feasibility of a Flat Collector Cooker using Vegetal Heat Transfer Fluid

Solar cookers currently produced are solar systems that use parabolic heat transfer to concentrate sun rays on a cooker. The new trend is focus on the cooker that uses a flat collector operating as a thermosiphon where the heat transfer fluid (oil) flows by natural convection. They are developed to address household needs at a lower cost, making them popular both in terms of research and use. Some of vegetable oils were previously investigated and which could be used as heat transfer fluids in such systems. A digital study using vegetable oil called "Kibi oil", an artisanal oil produced in Côte d’Ivoire, as a coolant, was conducted under poor weather conditions to calculate temperatures that could be reached in these cases. In the Sahelian zone, conditions are much better than these, and we can expect fairly excellent results. This study focused on temperature variation at different areas (1, 2, 3 and 4 specified in the diagram) of the cooker, on the mass flow of the fluid throughout the study day and to some quantities which enable to follow the performance of the solar collector of the stove. Sunlight measurements used are those of the city of Abidjan made in September, a very cloudy day with poor weather conditions. Temperature T3, very close to that of the hot plate, was around 110 °C between 10:30 am and 12:30 pm, which enables to cook certain dishes during this period. It should be noticed that at the exit of the flat panel collector, over the same period, the temperature is around 120 ° C. At that same time, the collector efficiency varies around 30%.

Characterization of Clay from Isan Ekiti Deposits for Making the Ceramic Water Purifier

Introduction: Despite the efforts of Governments and non-governmental organizations in sponsoring ceramic water purifier (CWP) filter project across the globe, some rural communities in Ekiti State, Nigeria are yet to benefit from it. One of the major technical difficulties hindering the making of CWP filter cells in many places was the adaptation to the sand, clay and sawdust mixture necessary to obtain the correct filter properties. Aim: In this study, some salient properties of clay from orudi, arade and oturo deposits at Isan Ekiti were assessed in the light of their usefulness for making the ceramic water filter cells. Methodology: The particle size distribution analysis and consistency tests were carried out on the crude clay. Also the shrinkage, effects of percentage constituents of burnout on porosity, filtration rate and quality of filtrate were measured, using standard methods. Results: Results show that arade has the appropriate technical properties for making the filter cell. The chosen clay sample has its deposit less than 2 kilometers to the point of making. About 56% of its particles are less than 0.075mm equivalent spherical diameter (ESD). A composition of ratio 50:50 by volume mixture of clay to sawdust has the porosity of 54. 55% while that of ratio 40:60 is 55.56%. Samples made of these batches were capable of reducing the water turbidity Neflometric Turbidity Unit (NTU) of contaminated water by 95%. The 50:50 samples have the higher capacity of reducing total coliform count by 50.28% as against 25.07% for 40:60 samples. Conclusion: Given appropriate facilities and training, with the abundant clay at arade deposit, the pottery center is a place where CWP filter cell factory could be established.

The Environmental Implications of the Rohingya Refugee Crisis in Bangladesh

Purpose: The main focus is to find out the environmental challenges that Bangladesh is dealing for the huge influx of Rohingya refugee people to Bangladesh. The research also aims to assess the dynamic situation of the crisis, identify the roles of Bangladesh government, NGOs as well as the International Organisations’ for Rohingya refugee crisis. Methodology: This study is context-dependent on information and an inductive data analysis. The paper uses a descriptive qualitative approach case study design that focuses on primary and secondary data showing the real ground of crisis. Data has been collected from the interviewees and experts. This research sets multiple methods of data collection including documents, policy, and historical analysis. Findings: Environmental imbalance occurred due to allocating 1,000 acres forest land for providing shelters to the refugees. Reserve forest has been destroyed endangering wild elephants. And it is causing landslides in the area, soil erosion, water scarcity, extreme heat wave, extreme rainfall, drought, deforestation, air pollution, and so on. Conclusion: This research leads to identifying the areas which have already been affected. The plans that need to work on to overcome the problems and that could provide necessary and sustainable solutions for Rohingya refugee. This study also could let people know the catastrophe Bangladesh is dealing and the impacts which can cause the ecological imbalance and failure the biodiversity of the areas in a greater way. This paper could bring benefit to society and make people conscious about the environment and also make them raise voices for the conservation of environment.

Vegetation Change Detection in the Niger Delta Region of Nigeria using Remote Sensing and GIS Techniques from 2000 to 2020

Generally, vegetation change through the conversion of the world’s forest land to other uses has assumed an increasing scale due to the unprecedented growth of the human population which increases the demand for food and land. Some believed that decrease in vegetation in the area is attributed to oil exploration and exploitation activities only. This study aimed to find out the nature of the vegetation change in the region from 2000 to 2020. The data used was remotely sensed images as Enhanced Vegetation Index (EVI) observed by Terra-MODIS, downloaded via United States Geological Survey (USGS). The Simple Image Differencing was performed on two images (February 18, 2000 and February 18, 2020) using IDRISI software. The result shows that all the states in the Niger Delta region experience both positive and negative change in vegetation cover. The positive change was observed around locations where agricultural plantations exists and within urban areas followed by oil and gas exploration and exploitation that damage the natural forest cover, while negative change was observed around farms where intensive rainy season farming takes place. It was recommended that deforested areas in the region should be reclaimed by planting economic trees as plantation to enhance greenness and maintain balance of the ecosystem. If intensive farming is necessary, it should be practiced sustainably to save the environment.

Multi-Stakeholder Approach in Natural Resources Management: The Case of Mida Creek and Gongoni-Marereni Mangrove Ecosystems in Kilifi County, Kenya

Multi-stakeholder approach has an overall improvement in conservation and management of mangrove forests resources, more so with a functional coordination framework among stakeholders. Mida creek and Gongoni-Marereni sites were compared in terms of the presence of the multi-stakeholders and the level of coordination and cooperation among stakeholders in conservation of mangrove forests. Data was gathered through a semi-structured interview questionnaire from Key Informants from the stakeholders present in the two sites. The data collected captured stakeholder presence on site, participation in mangrove conservation, and coordination and cooperation with others. There was a variation in multi-stakeholder participation in the two sites. Gongoni-Marereni site had less stakeholders compared to Mida creek which had more, with the latter having a greater participation of stakeholders. The Gongoni-Marereni site mangroves were degraded while in Mida creek had healthy mangroves.

Effect of Climate Change on Drinking Water Utilities in Nzoia River Basin, Kenya

Climate change is already having noticeable effects on water utilities in Nzoia River Basin. Extreme weather and climate-related occurrences are becoming more common and intense, as predicted by the Intergovernmental Panel on Climate Change (IPCC), Third Assessment Report. Because most water utilities are unprepared, the repercussions might be severe. The water supply infrastructure is built for resiliency and sustainability of operations during weather events or other circumstances that could potentially interrupt services; but when events that were historically considered to be “100-year” events happen more and more frequently, utilities must prepare for a new normal. These extreme events are occurring or being exceeded more regularly, and as a result, the past may no longer be a reliable predictor of the future. In Nzoia River Basin, the water supply infrastructure currently designed for historical climate conditions is more vulnerable to future weather extremes and climate change. This study assessed the effect of climate change on drinking water utilities in Nzoia River Basin. A cross-sectional survey design was used. Three counties were randomly selected from the basin for study with Busia representing the lower catchment, Kakamega middle catchment and Trans Nzoia upper catchment. The study was carried out from May, 2017 to September, 2017. In-depth expert interviews and brainstorming sessions were used to identify the climate change impacts affecting drinking water utilities experienced in the last ten years in the basin. A carefully selected team of water and climate change experts consisting of decision makers, practitioners, managers, scientists and technology adopters were used to rank the severity of the climate change impacts. Climate change occurring in Nzoia River Basin is expected to have a wide range of consequences for drinking water utilities. By assessing its potential impacts on water utilities, we become better positioned to make improvements today to decrease the future risks. The results of this study provide valuable insights for the national and county governments in preparing to effectively anticipate and respond to the relevant issues that they can expect to face in the coming century.

Plastic Pollutions in Aquatic Environment- A Review

Plastic pollution in aquatic ecosystems is a growing environmental concern, as it has the potential to harm ecology, imperil aquatic organisms and cost ecological damage. Although rivers and other freshwater environments are known to play an important role in carrying land-based plastic trash to the world's seas, riverine ecosystems are also directly impacted by plastic pollution. A detailed understanding of the origin, movement, fate, and effects of riverine plastic waste is critical for better quantifying worldwide plastic pollution transport and effectively reducing sources and dangers. In this review, we emphasize the current scientific state of plastic debris in rivers, as well as the existing knowledge gaps, providing a basic overview of plastics and the types of polymers commonly found in rivers and the threat they bring to aquatic ecosystems. We also go through the origins and fates of riverine plastics, as well as the mechanisms and factors that affect plastic debris transit and spatiotemporal variation. We give an overview of riverine plastic transport monitoring and modeling activities, as well as examples of typical values from throughout the world. Finally, we discuss what the future holds for riverine plastic research.