15 research outputs found
Ground Flora Species Richness and Diversity in Traditional Forests of Southwest, Nigeria
Diversity indices of tree species in tropical rainforest have been
studied, but less effort has been devoted to the ground flora studies
especially in sacred groves of tropical rainforest, Nigeria, as it
plays a critical role in nutrient cycling and energy flow within the
forest ecosystem. This study was carried out to determine the ground
flora species diversity, richness and density in five traditional
forests (Igbo-Ile, Igbo-Oba, Igbo-Olua, Igbo-Olodumare Igbo-Gbopo) of
southwestern Nigeria. The ground flora enumeration of 5 x 10m was laid
at the centre of 50 x 50m laid in each of the sacred grove. All plants
with dbh 64 10cm were identified and the frequency of occurrence
recorded. In all the Sacred Groves, a total of 14064 plants/ha
individual were recorded with 80 species distributed among 36 families.
Igbo-Oba had highest diversity index of 3.21, followed by
Igbo-Olodumare (2.80), Igbo-Ile (2.42). The least diversity index was
recorded in Igbo-Gbopo (1.97). Among the 36 families, maximum species
was recorded in Sterculiaceae (10), followed by Euphorbiaceae (5),
Apocynaceae (4), Combretaceae (4) and Sapindaceae (4). Among the
families with lowest frequencies (1) recorded are: Acanthaceae,
Araceae, Rutaceae, Sapotaceae, Solanaceae. The study concludes that
anthropogenic disturbances observed, e.g. farming, spiritual
engagements etc. around Igbo-Olua and Igbo-Gbopo might have contributed
to low diversity index compared to Igbo-Ile, Igbo-Oba and
Igbo-Olodumare where high diversity index was recorded. It is
recommended that to maintain high diversity index in the scared groves,
buffer zones should be created around the sacred groves
Ecological and Structural Characteristics of Riparian Forest in Omo Biosphere Reserve
An investigation on the structural characteristics of the riparian
forest in Omo Biosphere Reserve was carried out. The structure was
analyzed through diameter class distribution, basal area and breast
height. Riparian forest showed a major characteristic in the
physiognomy of forests along major river, streams and Upland vegetation
and the Core, Buffer and Transition zones that is highly variable in
the diameter class distribution (reserve J type), Mean basal area per
hectare for major river is 294,089.30/cm2/ ha, Stream 613.027/cm2/ha,
and Upland 205,648 cm3/ha. Mean basal area for core is 507,399.50
cm2/ha, buffer had 340,699 cm2/ha and transition 264,656 cm2/ha. While
mean volume per hectare for core is 7955.2 m3/ha, buffer 7260 m3/ha and
Transition 6254.4 m3/ha. Maximum dbh of 246 cm was obtained in the core
species. Many stands of riparian forests are facing various levels of
structural and floristic simplification, which include fundamental
transformations in vegetation physiognomy from dense stands to riparian
scrub or bare land
Five insights from the Global Burden of Disease Study 2019
The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 provides a rules-based synthesis of the available evidence on levels and trends in health outcomes, a diverse set of risk factors, and health system responses. GBD 2019 covered 204 countries and territories, as well as first administrative level disaggregations for 22 countries, from 1990 to 2019. Because GBD is highly standardised and comprehensive, spanning both fatal and non-fatal outcomes, and uses a mutually exclusive and collectively exhaustive list of hierarchical disease and injury causes, the study provides a powerful basis for detailed and broad insights on global health trends and emerging challenges. GBD 2019 incorporates data from 281 586 sources and provides more than 3.5 billion estimates of health outcome and health system measures of interest for global, national, and subnational policy dialogue. All GBD estimates are publicly available and adhere to the Guidelines on Accurate and Transparent Health Estimate Reporting. From this vast amount of information, five key insights that are important for health, social, and economic development strategies have been distilled. These insights are subject to the many limitations outlined in each of the component GBD capstone papers.Peer reviewe
Global age-sex-specific mortality, life expectancy, and population estimates in 204 countries and territories and 811 subnational locations, 1950–2021, and the impact of the COVID-19 pandemic: a comprehensive demographic analysis for the Global Burden of Disease Study 2021
BACKGROUND: Estimates of demographic metrics are crucial to assess levels and trends of population health outcomes. The profound impact of the COVID-19 pandemic on populations worldwide has underscored the need for timely estimates to understand this unprecedented event within the context of long-term population health trends. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 provides new demographic estimates for 204 countries and territories and 811 additional subnational locations from 1950 to 2021, with a particular emphasis on changes in mortality and life expectancy that occurred during the 2020–21 COVID-19 pandemic period. METHODS: 22 223 data sources from vital registration, sample registration, surveys, censuses, and other sources were used to estimate mortality, with a subset of these sources used exclusively to estimate excess mortality due to the COVID-19 pandemic. 2026 data sources were used for population estimation. Additional sources were used to estimate migration; the effects of the HIV epidemic; and demographic discontinuities due to conflicts, famines, natural disasters, and pandemics, which are used as inputs for estimating mortality and population. Spatiotemporal Gaussian process regression (ST-GPR) was used to generate under-5 mortality rates, which synthesised 30 763 location-years of vital registration and sample registration data, 1365 surveys and censuses, and 80 other sources. ST-GPR was also used to estimate adult mortality (between ages 15 and 59 years) based on information from 31 642 location-years of vital registration and sample registration data, 355 surveys and censuses, and 24 other sources. Estimates of child and adult mortality rates were then used to generate life tables with a relational model life table system. For countries with large HIV epidemics, life tables were adjusted using independent estimates of HIV-specific mortality generated via an epidemiological analysis of HIV prevalence surveys, antenatal clinic serosurveillance, and other data sources. Excess mortality due to the COVID-19 pandemic in 2020 and 2021 was determined by subtracting observed all-cause mortality (adjusted for late registration and mortality anomalies) from the mortality expected in the absence of the pandemic. Expected mortality was calculated based on historical trends using an ensemble of models. In location-years where all-cause mortality data were unavailable, we estimated excess mortality rates using a regression model with covariates pertaining to the pandemic. Population size was computed using a Bayesian hierarchical cohort component model. Life expectancy was calculated using age-specific mortality rates and standard demographic methods. Uncertainty intervals (UIs) were calculated for every metric using the 25th and 975th ordered values from a 1000-draw posterior distribution. FINDINGS: Global all-cause mortality followed two distinct patterns over the study period: age-standardised mortality rates declined between 1950 and 2019 (a 62·8% [95% UI 60·5–65·1] decline), and increased during the COVID-19 pandemic period (2020–21; 5·1% [0·9–9·6] increase). In contrast with the overall reverse in mortality trends during the pandemic period, child mortality continued to decline, with 4·66 million (3·98–5·50) global deaths in children younger than 5 years in 2021 compared with 5·21 million (4·50–6·01) in 2019. An estimated 131 million (126–137) people died globally from all causes in 2020 and 2021 combined, of which 15·9 million (14·7–17·2) were due to the COVID-19 pandemic (measured by excess mortality, which includes deaths directly due to SARS-CoV-2 infection and those indirectly due to other social, economic, or behavioural changes associated with the pandemic). Excess mortality rates exceeded 150 deaths per 100 000 population during at least one year of the pandemic in 80 countries and territories, whereas 20 nations had a negative excess mortality rate in 2020 or 2021, indicating that all-cause mortality in these countries was lower during the pandemic than expected based on historical trends. Between 1950 and 2021, global life expectancy at birth increased by 22·7 years (20·8–24·8), from 49·0 years (46·7–51·3) to 71·7 years (70·9–72·5). Global life expectancy at birth declined by 1·6 years (1·0–2·2) between 2019 and 2021, reversing historical trends. An increase in life expectancy was only observed in 32 (15·7%) of 204 countries and territories between 2019 and 2021. The global population reached 7·89 billion (7·67–8·13) people in 2021, by which time 56 of 204 countries and territories had peaked and subsequently populations have declined. The largest proportion of population growth between 2020 and 2021 was in sub-Saharan Africa (39·5% [28·4–52·7]) and south Asia (26·3% [9·0–44·7]). From 2000 to 2021, the ratio of the population aged 65 years and older to the population aged younger than 15 years increased in 188 (92·2%) of 204 nations. INTERPRETATION: Global adult mortality rates markedly increased during the COVID-19 pandemic in 2020 and 2021, reversing past decreasing trends, while child mortality rates continued to decline, albeit more slowly than in earlier years. Although COVID-19 had a substantial impact on many demographic indicators during the first 2 years of the pandemic, overall global health progress over the 72 years evaluated has been profound, with considerable improvements in mortality and life expectancy. Additionally, we observed a deceleration of global population growth since 2017, despite steady or increasing growth in lower-income countries, combined with a continued global shift of population age structures towards older ages. These demographic changes will likely present future challenges to health systems, economies, and societies. The comprehensive demographic estimates reported here will enable researchers, policy makers, health practitioners, and other key stakeholders to better understand and address the profound changes that have occurred in the global health landscape following the first 2 years of the COVID-19 pandemic, and longer-term trends beyond the pandemic. FUNDING: Bill & Melinda Gates Foundation
Traditional African Knowledge In Biodiversity Conservation
The tropical forest ecosystem is one of the most important ecosystems of the world, because it contains a large proportion of the world’s biodiversity and provides many environmental functions. Local communities have successfully conserved these resources that are of interest to them through laws and taboos. These range from fetish forests, burial-site forests, mystic-club forests and so on. People experience the sacred nature of forests, rivers, streams or mountains; through the beliefs they have on them as sources of power and of blessings and as abodes of their ancestors and the dead. Traditional religion and cultural practices thus contributed greatly to restricting and controlling the utilization of the resources. These traditional practices show that there is a big storehouse of knowledge built into traditional informal education provided orally and practically by parents, family and society. The loss of certain aspects of our cultures has reduced the possibility of imaginative new approaches. To achieve the objective of applying traditional Afrrcan knowledge in biodiversity conservation the interest of local communities must be properly addressed in policy formulation
Factors That Determine The Uses Of Some Timber Species In Irewole Local Government Ikire Osun State
The study identified the factors that determine the uses of some timber species in Osun State. The study covered Irewole Local Government Area, Ikire. Four wood-based industries were sampled namely, furniture, fuel wood selling, building construction/ carpentry and wood carving. A well structured questionnaire was administered in which 80 respondents were interviewed. The data were analysed using descriptive statistics.It was observed that 42.25% of the wood-based industry agreed strongly on hardness as a factor for wood product utilisation, 25% agreed on toughness, 15% choose direction of grain, 11.25% supported flexibility and 6.25% agreed strongly on stiffness. From the study It was obvious that hardness is the major determinant parameter adopted by the people in utilizing their wood products. In terms of source of getting the species used, 56.25% obtained their timber from sawmills, 27.5% from marketwhile 16.25% obtain their own directly from forest reserves. This indicates that sawmills are the major sources of producing various timber species needed for wood works in the study area. The result revealed that those in the age range 18 to 40 years were found to be active in the wood-based industries because it is energy sapping. The most common timber species used in the area were Millicia excelsa, Terminalia superba, Afzelia africana etc. .This paper recommended that research activities should be embarked upon to increase the quality of wood products so as to increase future utilization
Subnational mapping of HIV incidence and mortality among individuals aged 15-49 years in sub-Saharan Africa, 2000-18 : a modelling study
Background High-resolution estimates of HIV burden across space and time provide an important tool for tracking and monitoring the progress of prevention and control efforts and assist with improving the precision and efficiency of targeting efforts. We aimed to assess HIV incidence and HIV mortality for all second-level administrative units across sub-Saharan Africa. Methods In this modelling study, we developed a framework that used the geographically specific HIV prevalence data collected in seroprevalence surveys and antenatal care clinics to train a model that estimates HIV incidence and mortality among individuals aged 15-49 years. We used a model-based geostatistical framework to estimate HIV prevalence at the second administrative level in 44 countries in sub-Saharan Africa for 2000-18 and sought data on the number of individuals on antiretroviral therapy (ART) by second-level administrative unit. We then modified the Estimation and Projection Package (EPP) to use these HIV prevalence and treatment estimates to estimate HIV incidence and mortality by second-level administrative unit. Findings The estimates suggest substantial variation in HIV incidence and mortality rates both between and within countries in sub-Saharan Africa, with 15 countries having a ten-times or greater difference in estimated HIV incidence between the second- level administrative units with the lowest and highest estimated incidence levels. Across all 44 countries in 2018, HIV incidence ranged from 2.8 (95% uncertainty interval 2.1-3.8) in Mauritania to 1585.9 (1369.4-1824.8) cases per 100 000 people in Lesotho and HIV mortality ranged from 0.8 (0.7-0.9) in Mauritania to 676.5 (513.6-888.0) deaths per 100 000 people in Lesotho. Variation in both incidence and mortality was substantially greater at the subnational level than at the national level and the highest estimated rates were accordingly higher. Among second-level administrative units, Guija District, Gaza Province, Mozambique, had the highest estimated HIV incidence (4661.7 [2544.8-8120.3]) cases per 100 000 people in 2018 and Inhassunge District, Zambezia Province, Mozambique, had the highest estimated HIV mortality rate (1163.0 [679.0-1866.8]) deaths per 100 000 people. Further, the rate of reduction in HIV incidence and mortality from 2000 to 2018, as well as the ratio of new infections to the number of people living with HIV was highly variable. Although most second-level administrative units had declines in the number of new cases (3316 [81.1%] of 4087 units) and number of deaths (3325 [81.4%]), nearly all appeared well short of the targeted 75% reduction in new cases and deaths between 2010 and 2020. Interpretation Our estimates suggest that most second-level administrative units in sub-Saharan Africa are falling short of the targeted 75% reduction in new cases and deaths by 2020, which is further compounded by substantial within-country variability. These estimates will help decision makers and programme implementers expand access to ART and better target health resources to higher burden subnational areas. Copyright (C) 2021 The Author(s). Published by Elsevier Ltd.Peer reviewe
Review of Reduced Order Models for Heat and Moisture Transfer in Building Physics with Emphasis in PGD Approaches
International audienc