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Destruction of Urban Green Spaces: A Problem Beyond Urbanization in Kumasi City (Ghana)
Issue:
Volume 3, Issue 1, February 2014
Pages:
1-9
Received:
3 January 2014
Published:
30 January 2014
Abstract: Urbanization remains a single predominant factor that is continuously linked to the destruction of urban green spaces. This has created a knowledge gap of limited attention to other critical factors that deplete urban green spaces in diverse ways. Using Kumasi city (Ghana) which is suffering from rapid deterioration of its green spaces as a study area, this paper sought to fill this gap by exploring other key factors aside urbanization that are responsible for the destruction of urban green spaces. The paper relied on a case study research approach and triangulated data collection techniques such as in-depth interview, focus group discussion, personal observation and retrieval of archival data. In all, 30 in-depth interviews, 10 focus group discussions and numerous personal observations were carried out. It was observed that apart from urbanization, laxity in the enforcement of development controls, problem of ownership of green space lands, low priority to green spaces, uncooperative attitudes of the general public, poor culture of maintenance and lack of coordination among the allied bodies on green spaces play a critical role in the destruction of urban green spaces. The paper therefore concludes that for a city to have a preserved and sustainable urban green space, a broader public policy or city development plans that take into consideration the factors highlighted by the paper in addition to urbanization is essential.
Abstract: Urbanization remains a single predominant factor that is continuously linked to the destruction of urban green spaces. This has created a knowledge gap of limited attention to other critical factors that deplete urban green spaces in diverse ways. Using Kumasi city (Ghana) which is suffering from rapid deterioration of its green spaces as a study a...
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Australian Consumers’ Perceptions of Environmental and Agricultural Threats: The Associations of Demographic and of Psychographic Variables
Anthony Worsley,
Wei Wang,
Stacey Ridley
Issue:
Volume 3, Issue 1, February 2014
Pages:
10-18
Received:
13 December 2013
Published:
30 January 2014
Abstract: Currently little is known about the ways consumers perceive the issues and threats facing the agricultural sector. Understanding of the sector among the general community is important for its continued economic, social and environmental sustainability. Therefore we conducted an on-line survey among 1026 respondents drawn from each State and Territory in Australia. Initial examination of the responses showed most respondents held protectionist views about issues such as coal seam gas mining, imported food products and subsidies for agriculture and were aware of environmental and other threats. There were few city-country differences. Tertiary educated respondents tended to hold firmer opinions and more laissez-faire views than other respondents. Confirmatory factor analysis revealed two threat dimensions, one relating to threats to soil quality, the other about pollution and the survival of native animals. Stepwise multiple regression analyses of these dimensions showed that universalist values and trust in independent scientific information sources were positively associated with threat perceptions. The findings suggest that consumers generally are aware of agricultural issues, particularly those who hold strong universalist values. The respondents’ views of policy issues diverge in several respects from prevailing views of economic orthodoxy. Future consumer communication and research opportunities are discussed.
Abstract: Currently little is known about the ways consumers perceive the issues and threats facing the agricultural sector. Understanding of the sector among the general community is important for its continued economic, social and environmental sustainability. Therefore we conducted an on-line survey among 1026 respondents drawn from each State and Territ...
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Survey of the Levels of some Heavy Metals in Roadside Dusts along Katima Mulilo Urban Road Construction, Namibia
J. Abah,
P. Mashebe,
S. A. Onjefu
Issue:
Volume 3, Issue 1, February 2014
Pages:
19-27
Received:
4 January 2014
Published:
20 February 2014
Abstract: Roadside dusts pollutions with heavy metals continue to attract attention as more anthropogenic activities including urban road construction impacted on the natural metal loads of the environment. This study employed analytical procedures to investigate the concentrations of arsenic, lead, chromium, cadmium, cobalt, copper, nickel, manganese, vanadium, iron and tin in the roadside dusts along Katima Mulilo urban road construction. Replicate dusts samples collected from three different areas of the road and a quiet residential area (control) were digested by EPA method 3050B followed by Inductively Coupled Plasma-Optical Emission Spectrophotometer (ICP: Perkin Elmer Optima 7000 DV) analysis. The results of levels of the heavy metals revealed that iron recorded the highest concentration of 7491.13±0.15 mg/kg along the road construction while tin recorded the lowest value (0.27±0.13 mg/kg). Similar trend was observed at the control area located 1.5 km away from the road: iron recorded the highest concentration of 2327.17±0.12 mg/kg while tin recorded the lowest concentration (0.20±0.10 mg/kg). The analysis of variance of the heavy metal concentrations across the sample locations were statistically significant (p > 0.05). However, the levels of the heavy metals recorded cross the sampling areas were less than their soil maximum permissible concentrations. There are strong positive inter-elemental correlations between the sampling areas while result of the soil enrichment factors showed significant enrichment; which are related to common and input from anthropogenically induced sources respectively. The results of single element pollution indexes of the heavy metals showed low contaminations but elevated levels of arsenic and cadmium in all the sampling areas. These could become a potential source of health concern following environmental accumulation and non-biodegradation of the heavy metals. Thus, it is recommended among others that an environmental impact assessment should be carried out on gravel sites to be used in urban road construction to limit heavy metal contaminations of roadside dusts following their usage.
Abstract: Roadside dusts pollutions with heavy metals continue to attract attention as more anthropogenic activities including urban road construction impacted on the natural metal loads of the environment. This study employed analytical procedures to investigate the concentrations of arsenic, lead, chromium, cadmium, cobalt, copper, nickel, manganese, vanad...
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Heterogeneous Photocatalytic Degradation of Triton X-100 in Aqueous TiO2 Suspensions
Issue:
Volume 3, Issue 1, February 2014
Pages:
28-35
Received:
23 January 2014
Published:
20 February 2014
Abstract: The increasing utilization of surfactants generates a great amount of wastes. Surfactants and their more toxic degradation by-products in the environment affect the biota greatly. In particular, the low biodegradation of nonionic surfactants requires efficient oxidation treatments. In addition, the extracted contaminants by high concentrations of non-ionic surfactants in soil remediation may be completely treated using advanced oxidation process and thus the degradation of non-ionic surfactants needs to be checked in this case. The photocatalytic degradation of Triton X-100, a non-ionic surfactant, in aqueous titania suspensions was investigated as a function of catalyst dosage, pH, addition of hydrogen peroxide, potassium persulfate, and Tert-butyl alcohol. For the treatment of 20 mg/L Triton X-100 solutions, the optimum catalyst dosage and pH were determined to be 1 g/L and 6, respectively. The degradation efficiency of Triton X-100 by potassium persulfate was higher than that by hydrogen peroxide when the same mol of oxidants were used. Tert-butyl alcohol can strongly inhibit the photocatalytic oxidation reactions of Triton X-100. The degradation rates as a function of initial surfactant concentrations were interpreted by using a Langmuir-Hinshelwood model. With 0.2 g/L titania or even an additional 0.1 g/L hydrogen peroxide to completely degrade 1 mg/L phenanthrene in a 2 g/L Triton X-100 solution within 30 min, in this case the degradation efficiency of Triton X-100 was less than 5%. This proved that the strategy that surfactants were used as solubilizing agents for the removal of contaminants from soils followed by heterogeneous photocatalytic degradation was feasible.Within 120 min, 2 g/L of Triton X-100 can be degraded up to 67% by the addition of both 1 g/L titania and 1 g/L hydrogen peroxide. Under the right conditions, Triton X-100 can be completely degraded.
Abstract: The increasing utilization of surfactants generates a great amount of wastes. Surfactants and their more toxic degradation by-products in the environment affect the biota greatly. In particular, the low biodegradation of nonionic surfactants requires efficient oxidation treatments. In addition, the extracted contaminants by high concentrations of n...
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Calibrating the Rainfall-Runoff Model GR4J and GR2M on the Koulountou River Basin, a Tributary of the Gambia River
Vieux Boukhaly TRAORE,
Soussou SAMBOU,
Séni TAMBA,
Sidy FALL,
Amadou Tahirou DIAW,
Mohamed Talla CISSE
Issue:
Volume 3, Issue 1, February 2014
Pages:
36-44
Received:
13 January 2014
Published:
20 February 2014
Abstract: Rainfall runoff modelling is the first step in water resources management. It is the only way to simulate the hydrological behavior of the basin for a good evaluation of the potentiality of this in term of water production. Many approaches are actually in use. In physically distributed models, deterministic relations issued from conservation laws of physics (mass conservation, moment momentum conservation) are solved to describe the hydrological processes generating flow and their interaction. A DEM that should be as complete as possible is associed. Complexity of the equations to be solved and the huge amount of required data, uncertainty in these data make these models of limited use. Conceptual rainfall-runoff models are often preferred by hydrologists. These models are based on equations relating in a realistic manner the different terms of the hydrological cycle. They are simpler than determistic models and more flexible, Conceptual models are generally global. According to the way hydrological cycle terms are taken into account, conceptual model can be classified as empirical or not. The aim of this paper is to evaluate the availability of water in the Koulountou river basin, a tributary of Gambia River. This river basin should reinforce the water resource in a neighboring Kayanga river basin. Two empirical models at daily and monthly scale, the GR4J and GR2M have been used to describe the hydrological behavior of this basin. These models have been realized by the CEMAGREF, a French research Office. They use as inputs daily or monthly rainfall and potential evapotranspiration and river basin area, and give as output daily or monthly runoff. The first step before applying a hydrological model is to calibrate it that is to estimate the best parameters that fit the outputs in a given period. The Nash criterion has been used as goodness-of-fit criterion. Model performs satisfactory when this criterion is greater than 0.70 according to available data. A period from 1971 to 1994 has been selected. This period have been divided into three parts: one for calibration (1971-1978), one for validation (1978-1986), and the last for application (1987-1994). The results we obtain shows that GR4J and GR2M performs well in the Koulountou river basin since the Nash criterion is greater than 0.8.
Abstract: Rainfall runoff modelling is the first step in water resources management. It is the only way to simulate the hydrological behavior of the basin for a good evaluation of the potentiality of this in term of water production. Many approaches are actually in use. In physically distributed models, deterministic relations issued from conservation laws o...
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