Food web structure and trophic interactions of the tropical highland lake Hayq, Ethiopia

We generated a mass-balance model to figure out the food web structure and trophic interactions of the major functional groups of the Ethiopian highland Lake Hayq. Moreover, the study lay down a baseline data for future ecosystem-based investigations and management activities. Extensive data collection has been taken place between October 2007 and May 2009. Ecotrophic efficiency (EE) of several functional groups including phytoplankton (0.8) and detritus (0.85) was high indicating the utilization of the groups within the system. However, the EE of Mesocyclops (0.03) and Thermocyclops (0.30) was very low implying these resources were rather a ‘sink’ in the trophic hierarchy. Flows based on aggregated trophic level sensu Lindeman revealed the importance of both phytoplankton and detritus to higher trophic levels. The computed average transfer efficiency of 11.5% for the first four trophic levels was within the range for highly efficient African lakes. The primary production to respiration (P/R) ratio (1.05) of Lake Hayq indicates the maturity of the ecosystem. We also modeled the food-web by excluding Tilapia and reduced phytoplankton biomass to get insight into the mass balance before Tilapia was introduced. The analysis resulted in a lower system omnivory index (SOI = 0.016) and a reduced P/R ratio (0.13) that described the lake as immature ecosystem, suggesting the introduction of Tilapia might have contributed to the maturity of the lake. Tilapia in Lake Hayq filled an ecological empty niche of pelagic planktivores, and contributed for the better transfer efficiency observed from primary production to fish yield.     

A Parallel Computation Tool to Enable Dynamic Sensitivity and Model Performance Analysis of APEX: Evapotranspiration Modeling

Global sensitivity analysis can be used for assessing the relative importance of model parameters on model outputs. The sensitivity of parameters usually indicates a temporal variation due to variation in the environmental conditions (e.g., variation in weather or plant growth). In addition, the size of averaging window by which the outputs of a model are aggregated or averaged may impact parameter sensitivities. In this study, temporal variation of parameters sensitives, model performance, as well as the impact of the size of time‐averaging window on evapotranspiration (ET) prediction using the Agricultural Policy/Environmental eXtender (APEX) model are investigated. To achieve these goals, an open‐source package named PARAPEX was developed in R and used to perform dynamic sensitivity and model performance analysis of APEX using parallel computation. PARAPEX reduced the computation time from 5,939 to 379 s (using 20 and 1 computation nodes, respectively). The sensitivity analysis results indicated the parameters accounting for the reducing effect of plant cover on evaporation from the soil surface, the effect of soil on the plant root growth, and the effect of cycling and transformation dynamics of organic matter at the top soil layer as the top sensitive parameters based on the mean daily simulated ET and the Nash–Sutcliffe model performance measure. The dynamic performance analysis indicated poor ET predictions by APEX during the growing seasons. Editor's note : This paper is part of the featured series on Optimizing Ogallala Aquifer Water Use to Sustain Food Systems. See the February 2019 issue for the introduction and background to the series.     

Resource recovery potential from source-separated organic municipal solid waste: opportunities for organic fertilizer production and creating sustainable urban agriculture in Ethiopia

Journal of Material Cycles and Waste Management - Increasing waste production and its disposal into the environment without treatment and resource recovery is considered as a threat to the...     

Municipal solid waste generation in growing urban areas in Africa: current practices and relation to socioeconomic factors in Jimma, Ethiopia

As one of cities in the developing countries, a rapid population growth and industrial activities pose many environmental challenges for Jimma city, Ethiopia. One aspect of urban growth posing a threat on sustainable development is poor solid waste management, which results in environmental pollution. The purpose of this study is to evaluate the quantity, composition, sources of waste generated, their current disposal practices, and to recommend appropriate management technologies. The total waste generated daily in Jimma city was ca. 88,000 kg, and the average per capita generation rate was 0.55?±?0.17 kg/capita/day. Eighty-seven percent of the waste was produced by households and 13% by institutions, and a negligible fraction (0.1%) was generated by street sweepings. During the rainy season, 40% more waste was generated than in the dry season because of the increased availability of agricultural food product. Further analysis showed that biodegradable organic waste constitutes 54% by weight with an average moisture content of 60% that falls within the required limits for composting. The nonbiodegradable components constitute 46% of which 30% of it was nonrecyclable material. Only 25% of the community uses municipal containers for disposal at the selected landfill site. Fifty-one percent of the households disposed their waste in individually chosen spots, whereas 22% burned their waste. Finally 2% of households use private waste collectors. The socioeconomic analysis showed that higher family income and educational status is associated more with private or municipal waste collection and less with the application of backyard or open dumping. These insights into generated waste and management practice in Jimma city allow making suggestions for improved collection, treatment, and disposal methods. A primary conclusion is that the biodegradable waste is a major fraction having suitable properties for recycling. As such an economic benefit can be obtained from this waste while avoiding the need for disposal.     

Child passenger restraint use and emergency department--reported injuries: a special study using the National Electronic Injury Surveillance System-All Injury Program, 2004

INTRODUCTION: In 2004, more than 180,000 child passengers aged 相似文献   

Needle stick and sharps injuries among health care workers in Gondar city, Ethiopia

Background

All employees in health care settings handling needles or other sharps are at risk for needle stick and sharps injuries (NSSIs). Health care workers in under developed countries are at greater risk of infection from blood borne pathogens because of the lack of safety devices and the high prevalence of these pathogens.

Objectives

The aim of this study was to assess the prevalence of NSSIs and associated factors among health care workers in government health institutions in Gondar city, Ethiopia.

Methods

Institution based cross sectional study was conducted from May-December, 2010. The study included 344 health care workers who were selected from the source population using simple random sampling technique. Data were collected through interviews using structured and pre-tested questionnaire and the collected data were entered and analyzed using SPSS version 16.0.

Results

The prevalence of NSSIs among health care workers in the preceding 12 months was 106 (30.8%), of which 58 (54.7%) was reported by females. Lack of training on occupational health and safety, working more than 48 h/week, dissatisfaction with work environment and work culture, greater than 10 years of work experience and having low and moderate perception of risk were found to be significantly associated with NSSIs.

Conclusion

The study found high prevalence of NSSIs among health care workers. Effective training, ongoing awareness on the risk of hazards, preventive measures such as engineering control, and post-exposure prophylaxis following NSSIs are essential to reduce the risk of such injuries.     

Residents' willingness to pay for improved liquid waste treatment in urban Ethiopia: results of choice experiment in Addis Ababa

This paper discusses residents’ willingness to pay (WTP) for improved liquid waste treatment in Addis Ababa based on data collected in 2011 using random parameter logit model. Findings indicate that respondents are willing to contribute for improved liquid waste treatment with higher quantity and quality. Their mean WTP for the medium improvement scenario is found to be 15.53 ETB (0.93 USD) per month. The compensation surplus tends to increase from the status quo to the alternative scenarios with aggressive improvement. Finally, the paper concludes by indicating the socioeconomic difference across households, and sub-cities need to be considered in designing environmental protection plans for the city.     

Correlates of women’s environmental behaviors: a study in Pawe Woreda,Northwest Ethiopia

Available cross-country, macro-level evidence regarding gender differences in environmental behaviors shows women are more environmentally concerned and responsive than men. However, while such macro-level evidence helps understand patterns of women’s environmental behaviors at a much broader level, it does not allow deeper insights into particular patterns at a single location or in much smaller areas. Tailor-made interventions needed to address livelihood and environmental strategies of poor rural women become meaningful if studies aim at revealing context specific, local variations in women’s environmental behaviors. In this context, there is only little research for Ethiopia regarding what influences women’s response to environmental problems. The objective of this research was to describe women’s response to environmental problems in Pawe Woreda and examine the demographic, socioeconomic, and institutional correlates of this response, with particular emphasis to forest resources. Data were primarily obtained from a sample of 363 households in a multi-stage sample survey and were analyzed mainly using a multivariate logistic regression model. We found that all except one of the demographic and socioeconomic variables included in the model were found to be statistically significant correlates of woman’s environmental response, but the institutional variable was not significantly associated with a woman’s environmental response. However, the qualitative result for additional institutional issues revealed the importance of land tenure. Many of the results are in line with the existing literature.     

Nonfatal bathroom injuries among persons aged ≥15 years--United States, 2008

Problem

Information about where nonfatal unintentional injuries occur is limited, but bathrooms commonly are believed to be a hazardous location.

Methods

Data from a nationally representative sample of hospital emergency departments (ED) was used to quantify and characterize nonfatal unintentional bathroom injuries among people aged ≥ 15 years.

Results

In 2008, an estimated 234,094 nonfatal bathroom injuries were treated in EDs. Most injuries (81.1%) were caused by falls and 37.3% of injuries occurred when bathing, showering, or getting out of the tub or shower. Both injury and hospitalization rates increased with age.

Summary

These results suggest that bathrooms tend to be most hazardous for persons in the oldest age groups.

Impact on Industry

Bathroom injuries among all household members might be reduced by increasing awareness about potentially hazardous activities in the bathroom combined with simple environmental changes such as adding grab bars inside and outside the tub or shower.     

Environmental and habitat management: the case of Ethiopia and Ghana

This article examines the environment and habitat management experiences of Ethiopia and Ghana in the postindependence period (1960–2000). Based on extensive archival research, semistructured focused interviews of environment and habitat officers of the World Bank, the United Nations System and the International Union for the Conservation of Nature (IUCN) and personal professional field experiences, the paper argues that the uncritical adoption of externally generated discourses, narratives, policy guidelines, and strategies of environmental and habitat management has structured thought and action in both countries. The experience of both countries in defining and responding to environmental and human settlement management is explored from a political ecology perspective. The analysis indicates that both countries have essentially adopted a technocratic, state-centered, and unsustainable management strategy framework based on population control, poverty reduction, sustainable development, and capacity-building. It also suggests that international organizations such as the World Bank, INCN, and the United Nations system have been important sources of thought and action in both countries. Conversely, regional international organizations such as the Economic Commission for Africa, the Organization of African Unity and the African Development Bank have largely served as conduits for the diffusion of global discourses, narratives, policies and strategies. The need for adopting management policies and strategies that are based on principles of multiple engagement, decentralization, incentives, public education, and participation is underscored.