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B. J. Smallwood G. A. Wolff B. J. Bett C. R. Smith D. Hoover J. D. Gage A. Patience 《Die Naturwissenschaften》1999,86(7):320-324
On the highly productive Oman Margin of the Arabian Sea, where an intense permanent oxygen minimum impinges on the continental
slope, there is no relationship between oxygen concentration and sedimentary organic-carbon content. However, we provide photographic
and molecular evidence that benthic invertebrates play a significant role in the redistribution of organic matter. High densities
of spider crabs and brittle stars characterize a narrow band near the base of the oxygen minimum zone, where sediments have
depleted organic carbon contents and a remarkable lipid composition that is indicative of metabolic alteration of phytoplankton-derived
sterols by invertebrate detritivores. The distributions of sedimentary sterols and the high abundances of epifaunal crabs
and brittle stars suggest that the metabolism of the megabenthos profoundly influences the quality of organic matter in underlying
sediments.
Received: 12 June 1998 / Accepted in revised form: 26 January 1999 相似文献
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Jonathan O. Okonkwo Salia M. Lwenje Victor S. B. Mtetwa Patience N. Gumedze Mbuso M. Shilongonyane 《The Environmentalist》2001,21(3):205-209
Two hundred and fifty-seven urine samples collected from school children living in the Manzini region, Swaziland, were analysed for lead (Pb), using a graphite furnace atomic absorption spectrometer. The mean urine lead concentration for the urban schools ranged from 0.038–0.040 gml–1, while that for the rural schools ranged from 0.017–0.022 gml–1. The observed range shown by the urban schools was above the normal (for healthy humans) urine lead concentration of 0.035 gml–1. However, the mean urine lead concentration for the rural schools was found to be lower than this value. The mean urine lead concentration for the urban schools was significantly higher than that of the rural schools. The differences in the mean urine lead concentrations for boys and girls from both urban and rural schools were found not to be significant, despite the higher values shown by the girls. The difference in lead concentrations between urban and rural schools in Manzini was thought to be due to the traffic density within the urban area. 相似文献
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Patience U. Ajonina Gordon N. Ajonina Emmanuel Jin Fidèle Mekongo Isidore Ayissi Leonard Usongo 《国际发展与全球生态学杂志》2013,20(2):161-172
Socio-economic surveys were carried out in the Malimba and Mouanko communities in the Sanaga delta region of the Douala-Edea Wildlife Reserve, Cameroon, on the exploitation, processing and marketing of bivalves, with emphasis on gender aspects and impacts on the surrounding forest resources. Sixty people from 16 villages were sampled using a structured questionnaire with field observations documented during the peak fishing period (November 2000–June 2001). Results indicated a strong gender differentiation in the activity, with males dominating bivalve harvesting and shell processing and women dominating the processing for meat. Monthly bivalve meat production of 32.9 tons (197.4 tons per year) generated revenues of 65.4 million FCFA (74.9 million per year). Monthly shell production was put at 1380 tons (8040 tons per year) generating a monthly revenue of 74 million FCFA (444 million per year). Problems faced during exploitation, processing and marketing stages include physical, health and socio-economic: use of very depreciable rudimentary tools, shell injuries, fire and hot water burns, insect pests; blindness, deafness; inadequate storage facilities, transport and remoteness of the area. Bivalve processing activities using wood contributed to a total annual harvest of 50 986 m3 from the surrounding forest. Sustainable conservation measures geared towards poverty alleviation are proposed. 相似文献
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Paola M. Mwanamoki Naresh Devarajan Florian Thevenon Emmanuel K. Atibu Joseph B. Tshibanda Patience Ngelinkoto Pius T. Mpiana Kandasamy Prabakar Josué I. Mubedi Christophe G. Kabele Walter Wildi John Poté 《Environmental monitoring and assessment》2014,186(10):6821-6830
This study was conducted to assess potential human health risks presented by pathogenic bacteria in a protected multi-use lake-reservoir (Lake Ma Vallée) located in west of Kinshasa, Democratic Republic of Congo (DRC). Water and surface sediments from several points of the Lake were collected during summer. Microbial analysis was performed for Escherichia coli, Enterococcus (ENT), Pseudomonas species and heterotrophic plate counts. PCR amplification was performed for the confirmation of E. coli, ENT, Pseudomonas spp. and Pseudomonas aeruginosa isolated from samples. The results reveal low concentration of bacteria in water column of the lake, the bacterial quantification results observed in this study for the water column were below the recommended limits, according to WHO and the European Directive 2006/7/CE, for bathing water. However, high concentration of bacteria was observed in the sediment samples; the values of 2.65?×?103, 6.35?×?103, 3.27?×?103 and 3.60?×?108 CFU g?1 of dry sediment for E. coli, ENT, Pseudomonas spp. and heterotrophic plate counts, respectively. The results of this study indicate that sediments of the Lake Ma Vallée can constitute a reservoir of pathogenic microorganisms which can persist in the lake. Possible resuspension of faecal indicator bacteria and pathogens would affect water quality and may increase health risks to the population during recreational activities. Our results indicate that the microbial sediment analysis provides complementary and important information for assessing sanitary quality of surface water under tropical conditions. 相似文献
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Patience Ngelinkoto Florian Thevenon Naresh Devarajan Niane Birane Jeef Maliani Alain Buluku 《毒物与环境化学》2013,95(1):48-57
In this study, the concentrations of some metals in sediments and consumable fish from the Kwilu Ngongo River, province of Bas-Congo, Democratic Republic of Congo, are investigated. The digested muscle tissue, whole fish, and river sediment samples were subjected to trace element analysis by inductively coupled plasma mass spectroscopy and by using an automatic mercury analyzer. The highest values of trace metals in fish muscle tissue were found for Cr, Cu, Pb and Hg, with maximum values of 8.6 (Cr), 15.7 (Cu), 6.0 (Pb) and 3.3 (Hg) mg kg?1. These values are higher than maximum tolerable limits recommended by the European Commission Regulation for Food. The highest metal concentrations in sediments were 81 (Cr), 86 (Cu), 21 (Sb), 41 (Pb), and 0.8 (Hg) mg kg?1. Sediment toxicity tests using benthic crustaceans (ostracods) revealed mortality rates of up to 30% after six days of exposure to the sediments near the sugarcane industry outlet pipe discharge. The contamination of the sediments and fishes by the elements and the bio-accumulation of mercury in fish most likely arise from the adjacent agricultural fields where intensive sugarcane cultivation since 1925 has probably contaminated the soils through the long-term use of fertilizers and pesticides. 相似文献
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