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1.
Eolian (wind blown) sand constitutes a very serious problem to development in sandy desert lands and causes equally serious problems in lands that are undergoing desertification. In this paper, eolian sand movement due to bulk movement such as sand dune and ripple movement, sand drift by saltation, and sand storms by strong winds are discussed. Associated problems such as eolian sand encroachment on highways, farms, communities and industrial complexes are also discussed and workable solutions are offered. Solutions include chemical stabilization of the surface grains, fences to trap the blown sand and vegetation to prevent soil deflation. Vegetation is emphasized and recommended as the ultimate viable solution to combat desertification and eolian sand problems. 相似文献
2.
Adomako D Nyarko BJ Dampare SB Serfor-Armah Y Osae S Fianko JR Akaho EH 《Environmental monitoring and assessment》2008,141(1-3):165-175
Waters and sediments of Subin River, which flows through the industrial and commercial areas of Kumasi in the Ashanti region
of Ghana, were geochemically investigated to ascertain heavy metal pollution levels due to anthropogenic activities. The study
shows preoccupying pollution levels that constitute a threat to public and ecological systems. The waters of Subin River are
neutral to slightly basic, inferred from pH values of 6.89–7.65). Electric conductivity (EC) of the waters ranges from 822
to 1,821 μs/cm and the range of total dissolved solids (TDS) is from 409 to 913 mg/l. Toxic elements contents of sediments
and waters from 10 sites along the river were analysed by instrumental neutron activation analysis (INAA), and Al, As, Cd,
Cr, Cu and Zn were determined. The concentrations of Al, As, Cd, Cr, Cu and Zn in the waters range between 4.02–15.18, 0.007–0.16,
0.002–0.05, 0.001–0.019, 1.32–7.04 and 4.28–10.2 mg/l, respectively. The contamination factors (CF) computed for the elements
indicate that with the exception of sampling site S10, the sediments are polluted with Cd. Chromium contamination in the sediments
is observed at S6 and S7, where the CF values were 1.39 and 1.52, respectively. The pollution load indices (PLI) were low
(<1) and ranged from 0.14 to 0.75, suggesting that the overall sediment column of the river is not polluted. 相似文献
3.
Gyamfi Bright Akwasi Sarpong Steve Yaw Bein Murad A. 《Environmental science and pollution research international》2021,28(9):11016-11029
Environmental Science and Pollution Research - The debate on ecological matters that relate to the biomass emissions nexus has gained prominence and different scholars have suggested various forms... 相似文献
4.
Sheth AC Sastry C Yeboah YD Xu Y Agarwal P 《Journal of the Air & Waste Management Association (1995)》2003,53(4):451-460
Catalyst recovery studies were conducted for gasified chars produced from steam gasification of Illinois #6 coal catalyzed with two different catalyst systems. A ternary (43.5 mol% Li2CO3-31.5 mol% Na2COr-25 mol% K2CO3) and a binary (29 mol% Na2CO3-71 mol% K2CO3) eutectic catalyst system were used for gasifying coal. Various extraction schemes, such as water extraction, H2SO4 extraction, and acetic acid extraction, were evaluated with respect to their extraction efficiencies. Effects of major process variables, such as solvent-to-char ratio, mixing time, temperature, and concentration, on the extraction efficiency were evaluated. A process schematic for the entire catalyst recovery, regeneration, and recycle scheme was developed and the preliminary process economics were determined based on these extraction schemes. H2SO4 extraction was found to be the most desirable. It also turned out to be more attractive than a once-through throwaway system. 相似文献
5.
William Yaw Osei 《The Environmentalist》1996,16(3):231-239
Summary Agro-ecosystems in many of the developing economies are coming under increased pressure, especially in areas where population demands, weak economic growth, and debt burdens, are resulting in mass rural poverty and assault on environmental resources. The loss of forests is a double-edge blow for most rural and agricultural systems. The forests provide the resource substitutes for the many manufactured products which are scarce or physically and economically inaccessible, and they also provide congenial environments which support rural food systems by way of productive agricultural land opportunities.In many of the rural areas of Africa, in particular, forest stability is more threatened, and this requires both local and external responses to make sustainable development a possibility. This paper, which is based on a field study in Ghana by the author, identifies emerging socio-economic constraints in woodfuel systems in environments where demands on forest ecosystems are high. The degree to which such local socio-economic processes affect stability of forest ecosystems, and the conditions within which the research information could assist planners and resource managers towards sustainable use of forest ecosystems are analysed.Dr William Y. Osei was born in Ghana where he obtained a BA (Hons) Geography from the University of Ghana. He subsequently obtained an MA from Carleton University, Ottawa, Canada and a PhD from the University of Western Ontario, London, Canada. With teaching experience in Geography at the Canadian universities of Western Ontario, Brandon and Victoria, he currently holds the position of Assistant Professor in the Department of Geography at Algoma University College. 相似文献
6.
Atul C. Sheth Chandramouli Sastry Yaw D. Yeboah Yong Xu Pradeep Agarwal 《Journal of the Air & Waste Management Association (1995)》2013,63(4):451-460
Abstract Catalyst recovery studies were conducted for gasified chars produced from steam gasification of Illinois #6 coal catalyzed with two different catalyst systems. A ternary (43.5 mol% Li2 CO3 –31.5 mol% Na2 CO3 –25 mol% K2 CO3 ) and a binary (29 mol% Na2 CO3 –71 mol% K2 CO3 ) eutectic catalyst system were used for gasifying coal. Various extraction schemes, such as water extraction, H2 SO4 extraction, and acetic acid extraction, were evaluated with respect to their extraction efficiencies. Effects of major process variables, such as solvent-to-char ratio, mixing time, temperature, and concentration, on the extraction efficiency were evaluated. A process schematic for the entire catalyst recovery, regeneration, and recycle scheme was developed and the preliminary process economics were determined based on these extraction schemes. H2 SO4 extraction was found to be the most desirable. It also turned out to be more attractive than a once-through throwaway system. 相似文献
7.
Data obtained from a sample of technical, professional and administrative/managerial employees (N = 214) in Singapore were used to examine the cross-cultural generalizability of a version of Gould's career planning model. The recursive model depicts the mechanisms through which career planning affects career behavior (career strategy) and attitudes (career satisfaction, self-esteem at work and career commitment) and thereby reinforce the career planning function. Path analysis results of the four structural equations provided modest support for the hypothesized relations. In addition to the hypothesized relations, the results revealed some significant direct paths that were not hypothesized. Limitations of the study, implications of the findings and a direction for future studies are discussed. 相似文献
8.
Biological assessment of aquatic ecosystems is widely employed as an alternative or complement to chemical and toxicity testing due to numerous advantages of using biota to determine ecosystem condition. These advantages, especially to developing countries, include the relatively low cost and technical requirements. This study was conducted to determine the biological impacts of aquaculture operations on effluent-receiving streams in the Ashanti Region of Ghana. We collected water, fish and benthic macroinvertebrate samples from 12 aquaculture effluent-receiving streams upstream and downstream of fish farms and 12 reference streams between May and August of 2009, and then calculated structural and functional metrics for biotic assemblages. Fish species with non-guarding mode of reproduction were more abundant in reference streams than downstream (P?=?0.0214) and upstream (P?=?0.0251), and sand-detritus spawning fish were less predominant in reference stream than upstream (P?=?0.0222) and marginally less in downstream locations (P?=?0.0539). A possible subsidy-stress response of macroinvertebrate family richness and abundance was also observed, with nutrient (nitrogen) augmentation from aquaculture and other farming activities likely. Generally, there were no, or only marginal differences among locations downstream and upstream of fish farms and in reference streams in terms of several other biotic metrics considered. Therefore, the scale of impact in the future will depend not only on the management of nutrient augmentation from pond effluents, but also on the consideration of nutrient discharges from other industries like fruit and vegetable farming within the study area. 相似文献
9.
Bekun Festus Victor Alola Andrew Adewale Gyamfi Bright Akwasi Yaw Sarpong Steve 《Environmental science and pollution research international》2021,28(37):51137-51148
Environmental Science and Pollution Research - Considering the prevailing wave of global warming and other environmental challenges, which can be attributed to increasing environmental pollution as... 相似文献
10.
Effah Nana Adwoa Anokye Wang Qinggang Owusu Godfred Matthew Yaw Otchere Octavia Ama Serwaa Owusu Bright 《Environmental science and pollution research international》2023,30(1):104-126
Environmental Science and Pollution Research - The study determines the development of the sustainability reporting domain using a dataset of publications extracted from the Web of Science (WoS)... 相似文献