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Stromberg JC Lite SJ Rychener TJ Levick LR Dixon MD Watts JM 《Environmental monitoring and assessment》2006,115(1-3):145-173
A portion of Arizona’s San Pedro River is managed as a National Riparian Conservation Area but is potentially affected by ground-water withdrawals beyond the conservation area borders. We applied an assessment model to the Conservation Area as a basis for monitoring long-term changes in riparian ecosystem condition resulting from changes in river water availability, and collected multi-year data on a subset of the most sensitive bioindicators. The assessment model is based on nine vegetation bioindicators that are sensitive to changes in surface water or ground water. Site index scores allow for placement into one of three condition classes, each reflecting particular ranges for site hydrology and vegetation structure. We collected the bioindicator data at 26 sites distributed among 14 reaches that had similar stream flow hydrology (spatial flow intermittency) and geomorphology (channel sinuosity, flood-plain width). Overall, 39% of the riparian corridor fell within condition class 3 (the wettest condition), 55% in condition class 2, and 6% in the driest condition class. Condition class 3 reaches have high cover of herbaceous wetland plants (e.g., Juncus and Schoenoplectus spp.) along the perennial stream channel and dense, multi-aged Populus-Salix woodlands in the flood plain, sustained by shallow ground water in the stream alluvium. In condition class 2, intermittent stream flows result in low cover of streamside wetland herbs, but Populus-Salix remain abundant in the flood plain. Perennial wetland plants are absent from condition class 1, reflecting highly intermittent stream flows; the flood plain is vegetated by Tamarixa small tree that tolerates the deep and fluctuating ground water levels that typify this reach type. Abundance of herbaceous wetland plants and growth rate of Salix gooddingii varied between years with different stream flow rates, indicating utility of these measures for tracking short-term responses to hydrologic change. Repeat measurement of all bioindicators will indicate long-term trends in hydro-vegetational condition. 相似文献
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Adu-Kumi S Kareš R Literák J Borůvková J Yeboah PO Carboo D Akoto O Darko G Osae S Klánová J 《Environmental science and pollution research international》2012,19(6):1963-1970
Urban, suburban and rural background air samples were collected in southern Ghana in 2008 employing polyurethane foam disc passive air samplers (PAS). PAS were analysed for organochlorine pesticides (OCPs), namely hexachlorocyclohexanes (α-, β-, γ- and δ-hexachlorocyclohexane), dichlorodiphenyltrichloroethane including metabolites (o,p'- and p,p'-DDT, DDE and DDD), hexachlorobenzene, pentachlorobenzene, aldrin, dieldrin, endrins (endrin, endrin aldehyde and endrin ketone), isodrin, heptachlors (heptachlor, heptachlor epoxide A and heptachlor epoxide B), chlordanes (α-, β-chlordane, oxychlordane and trans-nonachlor), endosulfans (α- and β-endosulfan and endosulfan sulphate), methoxychlor and mirex using a gas chromatograph coupled to a mass spectrometer. The levels of OCPs ranged for the individual pesticides from below limit of quantification to 750 pg m(-3) (for α-endosulfan), and current agricultural application seemed to be the main primary source of most abundant pesticides. Re-volatilization of previously used pesticides from contaminated soils could not be ruled out either as potential secondary source of contamination, especially in warm and dry seasons and periods of intensive agricultural activities. Higher atmospheric concentrations were observed in November and December during the dry season compared to lower concentrations observed in June, July and August when the country experiences heavy rains. The highest seasonal variation was observed for currently used pesticides as α-endosulfan. A p,p'-DDT/p,p'-DDE ratio suggested recent inputs of fresh technical DDT. 相似文献
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Philip W. Gassman Edward Osei Ali Saleh Larry M. Hauck 《Journal of the American Water Resources Association》2002,38(2):423-438
ABSTRACT: A National Pilot Project (NPP) on Livestock and the Environment was initiated in 1992 to help provide solutions to environmental problems associated with livestock production. A major development of the NPP was the Comprehensive Economic and Environmental Optimization Tool‐Livestock and Poultry (CEEOT‐LP), an integrated modeling system designed to produce economic and environmental indicators for alternative policy scenarios applied to intensive livestock production watersheds. The system consists of a farm‐level economic model (FEM) and two environmental models: the field‐scale APEX model and the watershed‐level SWAT model. To date, CEEOT‐LP has been applied to two watersheds in Texas and one in Iowa. Predicted reductions in P losses for two P‐based manure application rate scenarios, relative to baseline conditions, ranged from ?4 to ?54 percent across the three watersheds; however, N loss impacts ranged from a decrease of 34 percent to an increase of 79 percent. For five other alternative scenarios that were simulated for only one watershed, N and P loss impacts ranged between a reduction of 78 percent to an increase of 20 percent. Aggregate watershed‐level economic impacts of the seven scenarios spanned a spectrum of a 27 percent decrease to a 25 percent increase in profit, relative to the baseline. 相似文献
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Muthusamy Subbulakshmi Anandharaj Swetha Juliet Kumar Ponnusamy Senthil Meganathan Yogesan Vo Dai-Viet Nguyen Vaidyanathan Vinoth Kumar Muthusamy Shanmugaprakash 《Environmental Chemistry Letters》2022,20(5):3199-3234
Environmental Chemistry Letters - Most fossil fuel-derived polymers used for food packaging are non-biodegradable and induce pollution by microplastic, calling for safer material. Here we review... 相似文献
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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
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Community involvement is fundamental to the management of multijurisdictional river basins but, in practice, is very difficult
to achieve. The Murray-Darling basin, in Australia, and the Mekong River basin in Southeast Asia are both cooperatively managed
multijurisdictional river basins where the management authorities have expressed an aim of community involvement. In the Murray-Darling
basin vigorous efforts have promoted a culture of community consultation throughout each of the state jurisdictions involved,
although true participation has not necessarily been achieved. In the Mekong basin the community is much more diverse and
the successes so far have been largely at the local level, involving action in subsections of the basin. These case studies
suggest that community involvement in the form of community consultation across large multijurisdictional river basins is
achievable, but more comprehensive participation is not necessarily possible. 相似文献
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Michael Ackah Alfred Kwablah Anim Eva Tabuaa Gyamfi Nafisatu Zakaria John Hanson Delali Tulasi Sheriff Enti-Brown Esther Saah-Nyarko Nash Owusu Bentil Juliet Osei 《Environmental monitoring and assessment》2014,186(1):621-634
The heavy metals (Fe, Zn, Pb, Ni, Cr, Co, and Cd) burden in wastewater, soil, and vegetable samples from a wastewater irrigated farm located at KorleBu, Accra has been investigated. Flame atomic absorption spectrometry after microwave digestion using a combination of HNO3, HCl, and H2O2 (for water), and HNO3 and HCl (for soil and vegetables). The mean concentrations (in milligrams per kilogram) of heavy metals in the soil samples were in the order of Fe (171?±?5.22)?>?Zn (36.06?±?4.54)?>?Pb (33.35?±?35.62)?>?Ni (6.31?±?8.15)?>?Cr (3.40?±?3.63)?>?Co (1.36?±?0.31)?>?Cd (0.43?±?0.24), while the vegetables were in the order of Fe (183.11?±?161.2)?>?Zn (5.38?±?3.50)?>?Ni (3.52?±?1.27)?>?Pb (2.49?±?1.81)?>?Cr (1.46?±?0.51)?>?Co (0.66?±?0.25)?>?Cd (0.36?±?0.15). The bioconcentration factors suggest environmental monitoring for the heavy metals as follows: Cd (0.828), Cr (0.431), Ni (0.558), Co (0.485), and Fe (1.067). Estimated daily intakes were very low for both children and adults except Fe (0.767 mg/kg/day) in children. The population that consume vegetables from the study area were, however, estimated to be safe based on the results obtained from the health risk index, which were all?<?<1. The sodium absorption ratio according to FAO (1985) classifications indicate that the wastewater in the study area is unsuitable for irrigation purposes. 相似文献
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Persistent organochlorine pesticide residues in fish, sediments and water from Lake Bosomtwi, Ghana 总被引:3,自引:0,他引:3
Some organochlorine pesticide residues in tilapia fish (Tilapiazilli), sediment and water samples from Lake Bosomtwi (the largest natural lake in Ghana) were determined to find out the extent of pesticide contamination and accumulation in the lake. The extracted residues were analyzed on a micro-capillary gas chromatograph equipped with electron capture detector. DDE (p,p'-1,1-dichloro-2,2-bis-(4-chlorophenyl)ethylene) was the predominant residue in all the samples analyzed; detected in 82% of water samples, 98% of sediment samples and 58% of fish samples at concentrations of 0.061+/-0.03 ng g(-1), 8.342+/-2.96 ng g(-1) and 5.232+/-1.30 ng g(-1), respectively. DDT (p,p'-1,1,1-trichloro-2,2-bis-(4-chlorophenyl)ethane) was detected in 78% at a mean concentration 0.012+/-0.62 ng g(-1) of water samples analyzed. The mean concentrations of DDT in sediments and fish were 4.41+/-1.54 ng g(-1) and 3.645+/-1.81 ng g(-1), respectively. The detection of lower levels of DDT than its metabolite, DDE, in the samples implies that the presence of these contaminants in the lake is as result of past usage of the pesticides. 相似文献
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Robert L. Getty Juliet Getty 《International journal of occupational safety and ergonomics》2013,19(2):161-194
AbstractA holistic view is essential for quality initiatives such as Total Quality Management (TQM), Standard No. ISO 9001:1994 (International Organization for Standardization [ISO], 1994), Concurrent Engineering, Business Reengineering, and Business Process Improvement. The challenge is knowing how to transition from this theoretical concept to implementation. The relationship between quality interest and anergonomics program will be the focus of this discussion. An ergonomics oriented improvement program includes (a) ergonomics or fitting the job to the person; (b) integration of operations management, safety engineering, medical management, and employees as co-owners of the process; (c) the emphasis of ergonomic precepts in the engineering of new processes and improvement of current processes; and (d) the emphasis of employees taking responsibility for their own well being and the improvement of their work environment. The parallel between the continuous improvement process delineated by the quality-system requirements in Standard No. ISO 9001:1994 (ISO, 1994) and the improvement contributions of ergonomics are very revealing (Getty, Abbott, & Getty, 1995). It is the contention of this approach that if the precepts of ergonomics were applied to the work environment, it would support the objective of world class quality and productivity, resulting in improved global competitiveness of businesses. 相似文献