Traditional management and conservation of shea trees (<Emphasis Type="Italic">Vitellaria paradoxa</Emphasis> subspecies <Emphasis Type="Italic">nilotica</Emphasis>) in Uganda

Traditional practices are universally recognised as a basis for conservation of biodiversity. However, such practices are often not included in natural resource conservation policies. This study assessed local conservation practices of shea trees (Vitellaria paradoxa) within different farming systems in Uganda and developed conservation guidelines for the species. The assessment involved 300 respondents, 15 focus groups and 41 key informants. Content analysis was used to identify the most important management and conservation practices. Local uses were categorised on the basis of shea tree products while differences in conservation practices were analysed using the Friedman test. The results show that eight shea tree products are used for 36 different purposes. Respondents’ age significantly influenced their knowledge about the shea tree. Traditional conservation practices include on-farm retention during cultivation and the use of folklore (mainly taboos), customs and rituals. Traditional management practices include weeding, bush burning, pollarding and pruning. Based on the current management and traditional conservation practices, a framework for the conservation of shea trees is proposed for integration into conservation policy decisions.     

Concentration gradient patterns of aerosol particles near interstate highways in the Greater Cincinnati airshed

The objective of this study was to determine if there is an exposure gradient in particulate matter concentrations for people living near interstate highways, and to determine how far from the highway the gradient extends. Air samples were collected in a residential area of Greater Cincinnati in the vicinity of two major highways. The measurements were conducted at different distances from the highways by using ultrafine particle counters (measurement range: 0.02-1 microm), optical particle counters (0.3-20 microm), and PM2.5 Harvard Impactors (0.02-2.5 microm). The collected PM2.5 samples were analyzed for mass concentration, for elemental and organic carbon, and for elemental concentrations. The results show that the aerosol concentration gradient was most clearly seen in the particle number concentration measured by the ultrafine particle counters. The concentration of ultrafine particles decreased to half between the sampling points located at 50 m and 150 m downwind from the highway. Additionally, elemental analysis revealed a gradient in sulfur concentrations up to 400 m from the highway in a residential area that does not have major nearby industrial sources. This gradient was qualitatively attributed to the sulfate particle emissions from diesel engine exhausts, and was supported by the concentration data on several key elements indicative of traffic sources (road dust and diesel exhaust). As different particulate components gave different profiles of the diesel exposure gradient, these results indicate that no single element or component of diesel exhaust can be used as a surrogate for diesel exposure, but more comprehensive signature analysis is needed. This characterization is crucial especially when the exposure data are to be used in epidemiological studies.     

Factors leading to the evolution and maintenance of a male ornament in territorial species

Male ornamentation is assumed to have evolved primarily from selection by female mate choice. Yet this is only one possible reason for ornament evolution. Ornaments might also be useful in aggressive competition by improving opponent assessment between males, or they might function to enhance signal detection by making males more conspicuous in the environment. We tested both these ideas in territorial Anolis lizards in which female choice is either absent or secondary to males competing for territories that overlap female home ranges. Male tail crests only evolved in species in which territory neighbors were distant, consistent with the signal detection hypothesis. Once the tail crest had evolved, however, it seems to have become a signal in itself, with variation in the frequency and size of tail crests within species correlating with variables predicted by the aggressive competition hypothesis. Our study presents an apparent example of a male ornament in which the selection pressure leading to variation among species in ornament expression is different from the selection pressure acting on variation within species. The Anolis tail crest is therefore likely to be an exaptation. We caution that conclusions made on the evolution of male ornaments are dependent on the phylogenetic perspective adopted by a study. Studies restricted to single species are useful for identifying selection pressures in contemporary settings (i.e., the current utility of traits), but may lead to erroneous conclusions on the factors that initially lead to the origin of traits.     

GC/MS analysis of polynuclear aromatic hydrocarbons in sediment samples from the Niger Delta region

Thirteen sediment samples from different locations in the Niger Delta region of Nigeria were analyzed for the presence of 16 polynuclear aromatic hydrocarbons (PAHs) via gas chromatography/mass spectrometry. The specific target compounds for this study included naphthalene, acenaphthylene, acenaphthene, flourene, phenanthrene, anthracene, flouranthene, pyrene, benz[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[k]flouranthene, benzo[a]pyrene, benzo[ghi]perylene, dibenz[a,h]anthracene, and indeno[1,2,3-cd]pyrene. Four isotopically labeled polynuclear aromatic hydrocarbons (acanaphthene-d10, phenanthrene-d10, chrysene-d12 and perylene-d12) were used for internal standardization. All 16 PAHs were found in most of the thirteen samples with concentration ranging from 0.1 microg/kg to 28 microg/kg. It was also found that the 5 and 6-ring PAHs were present in higher concentrations than all the other compounds, indicating their high resistance to microbial degradation.     

Soil carbon sequestration and associated economic costs for farming systems of the Indo-Gangetic Plain: A meta-analysis

Soil organic carbon sequestration rates over 20 years based on the Intergovernmental Panel for Climate Change (IPCC) methodology were combined with local economic data to determine the potential for soil C sequestration in wheat-based production systems on the Indo-Gangetic Plain (IGP). The C sequestration potential of rice-wheat systems of India on conversion to no-tillage is estimated to be 44.1 Mt C over 20 years. Implementing no-tillage practices in maize-wheat and cotton-wheat production systems would yield an additional 6.6 Mt C. This offset is equivalent to 9.6% of India's annual greenhouse gas emissions (519 Mt C) from all sectors (excluding land use change and forestry), or less than one percent per annum. The economic analysis was summarized as carbon supply curves expressing the total additional C accumulated over 20 year for a price per tonne of carbon sequestered ranging from zero to USD 200. At a carbon price of USD 25 Mg C⁻¹, 3 Mt C (7% of the soil C sequestration potential) could be sequestered over 20 years through the implementation of no-till cropping practices in rice-wheat systems of the Indian States of the IGP, increasing to 7.3 Mt C (17% of the soil C sequestration potential) at USD 50 Mg C⁻¹. Maximum levels of sequestration could be attained with carbon prices approaching USD 200 Mg C⁻¹ for the States of Bihar and Punjab. At this carbon price, a total of 34.7 Mt C (79% of the estimated C sequestration potential) could be sequestered over 20 years across the rice-wheat region of India, with Uttar Pradesh contributing 13.9 Mt C.     

Carbonation of brine impacted fractionated coal fly ash: implications for CO2 sequestration

Coal combustion by-products such as fly ash (FA), brine and CO(2) from coal fired power plants have the potential to impact negatively on the environment. FA and brine can contaminate the soil, surface and ground water through leaching of toxic elements present in their matrices while CO(2) has been identified as a green house gas that contributes significantly towards the global warming effect. Reaction of CO(2) with FA/brine slurry can potentially provide a viable route for CO(2) sequestration via formation of mineral carbonates. Fractionated FA has varying amounts of CaO which not only increases the brine pH but can also be converted into an environmentally benign calcite. Carbonation efficiency of fractionated and brine impacted FA was investigated in this study. Controlled carbonation reactions were carried out in a reactor set-up to evaluate the effect of fractionation on the carbonation efficiency of FA. Chemical and mineralogical characteristics of fresh and carbonated ash were evaluated using XRF, SEM, and XRD. Brine effluents were characterized using ICP-MS and IC. A factorial experimental approach was employed in testing the variables. The 20-150 μm size fraction was observed to have the highest CO(2) sequestration potential of 71.84 kg of CO(2) per ton of FA while the >150 μm particles had the lowest potential of 36.47 kg of CO(2) per ton of FA. Carbonation using brine resulted in higher degree of calcite formation compared to the ultra-pure water carbonated residues.     

Investigating the chromium status,heavy metal contamination,and ecological risk assessment via tannery waste disposal in sub-Saharan Africa (Kenya and South Africa)

Environmental Science and Pollution Research - To mitigate the negative environmental and public health concerns associated with increased industrial discharges amid the rapid industrial growth,...     

Gender influences decisions to change land use practices in the tropical forest margins of Jambi,Indonesia

This study explores the role of gender as a factor in decision making about alternative land use options and in responses to new investment opportunities, which has received little attention to date. An observational study to determine the different factors affecting male and female decisions to change land use at the individual level in a forest margin landscape in Jambi (Sumatra, Indonesia) was combined with a set of role playing games (RPGs) designed to assess participant responses in a simulated social setting of women-only and men-only groups. The RPG included simulated agents offering new opportunities to convert or conserve agroforest. In the study area, rubber (Hevea braziliensis) agroforests that support high biodiversity and carbon storage are giving way to monoculture rubber and oil palm (Elaeis guineensis) plantations. When women from both the upland and lowland villages played the RPGs, external investors proposing logging or oil palm conversion were approached very positively and the resulting land use change was more dynamic and extensive than in the equivalent men-only groups. Consequently, women outperformed men in achieving income targets. In lowland areas gender is strongly associated with land use change, while in the uplands the level of conservation awareness plays a more crucial role in the maintenance of rubber agroforests. Based on the data, and contrary to expectations and gender stereotypes, it is expected that the greater involvement of women in landscape level decision making will increase emissions from deforestation and forest degradation in the area, posing further challenges to efforts to reduce such emissions.     

Effects of radiation exposure on brain health: a state of the art and new challenges

Environmental Science and Pollution Research - Good brain health refers to a condition in which a person may fully realize their talents and improve their psychological, emotional, cognitive, and...