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1.
Patrick D. Mathews Ana C.M.F. Patta Gabriella S. Gama Omar Mertins 《Comptes rendus biologies》2018,341(1):16-19
The occurrence of copepods ergasilid was investigated in two species of cichlids of economic importance for aquaculture in the Amazon region: Cichla monoculus and Chaetobranchus semifasciatus. The fish were collected from a semi-intensive fish farm, near the city of Nauta, Loreto State, Peru. Copepods were found in the gill filaments of 44 of 85 specimens (51.7%) of C. monoculus and in eight of 30 (26.6%) specimens of C. semifasciatus. The parasite was identified as Ergasilus coatiarus based on its morphological features. The occurrence did not vary significantly with host size (P ≥ 0.05) in both species. This is the first report of E. coatiarus parasitizing C. semifasciatus in the Amazon basin and the first report in C. monoculus from Peru. The high occurrence of these copepods in the present study points out the need of improving the strategies of parasitic prevention and control in order to better prevent future disease outbreaks. 相似文献
2.
Oliver Phillips 《Biodiversity and Conservation》1993,2(1):18-38
New data shows that edible fruit and nut production in Amazonian forests is substantially lower than most conservationists assume. Direct measures of production in Amazonian Peru show that two terra firma forest types produced significantly less edible fruit than an alluvial soil forest. Swamp forest produced more edible fruit than any other forest type measured. Palms produce 60% of edible fruit productivity, averaged over three forest types, but the most preferred palm fruits are difficult to harvest because they are borne too high for easy access by collectors. Forest fruit collection in Amazonia is less productive in the short-term than all other food-producing activities except for hunting and cattle ranching. Technological, social and political changes are essential so that sustainable but intrinsically low-yielding extractive activities like fruit collecting become more attractive to Amazonians. 相似文献
3.
J. E. Péfaur 《Plant Ecology》1982,49(3):163-171
A study of the floristic composition of the plant communities of the Lomas was carried out in the Coastal Range of Arequipa, Peru. Data on the seasonal and elevational variation of those communities was obtained by monthly censusing a 20-meter circle sampling stations established at 100 m intervals from 300 to 1 000 m of elevation. The 80 recorded plants belong to 60 genera and to 20 families. Dominating life forms are Therophytes and Chamaephytes. Four vegetational zones (xeric, subxeric, mesic, and submesic), are separated by significant differences in the number of plants of each zone. Considering the entire Lomas transect, no significant statistical differences among the seasons were found. The floristic relationship among the altitudinal samples was found to be a reflection of a moisture pattern. The persistence in the Lomas of a mesophytic flora could be the result of a continuous adaptation to the fogginess and reduced solar radiation of this particular zone in a desert area.This study was supported by the Universidad Nacional de San Agustin, Arequipa, Perú, and by the Universidad de Los Andes through the Consejo de Desarrollo Cientifico y Humanistico (Proycet C-142-79). Amelia Díaz de Paseual, William E. Duellman, Evaristo López, Luis Malaret, Mario Ricardi and Antonio Vivas made helpful comments and criticisms. Field trips were shared with José Dávila, Evaristo López and Alberto Nuñez. The identification of plants was checked by Ramón Ferreyra and Oscar Tovar of the Museo Javier Prado, Lima, Perú, and Alwing Gentry of the Missouri Botanical Garden. I am grateful to all these institutions and people. 相似文献
4.
John R. Claxton Hugo Zambrano Pedro Ortiz Carlos Amorós Elio Delgado Edwin Escurra Michael J. Clarkson 《Parasitology international》1997,46(4):281-288
Fasciolosis is recognised as a major problem in dairy cattle in parts of Peru. A longitudinal study of dairy cattle in Cajamarca, Peru was used to determine the annual pattern of infection with Fasciola hepatica. After a gradual increase from January, peak egg production occurred in August/September and then dropped rapidly. Indirect indicators of infection, eosinophil counts and serum liver-enzyme activities, indicated that the major period of new infection in cattle occurred from December to May each year. Examination of snails demonstrated that, although there was no clear annual cycle in snail abundance, the majority of snails infected with cercariae were found between January and March. Climatological data indicated that there was sufficient moisture for development of the parasite during a limited period each year, coinciding with the period of maximum abundance of cercaria-infected snails, but that irrigation could substantially alter the amount of water available. Infections in tracer-calves decreased from December to September, with little or no infection occurring between June and August, but suggesting that there could be significant infection prior to December. Thus a defined annual cycle of infection was observed, where cattle acquired infection from December to May and this infection matured to produce peak egg counts in August/September which were then available to infect the intermediate host for the next cycle of infection. 相似文献
5.
This study addresses the impact of small-scale gold mining on the environment and communities of the Puyango River basin in
the southwest of Ecuador between 1999 and 2001. Our primary objectives were to measure mercury, manganese, and lead in the
river, to identify pathways of population exposure, and biological indicators of human exposure. A multi-method design at
the catchment scale was applied to the analysis of water, sediments, and particulate matter for mercury, lead, and manganese
over two different seasons. A household survey was undertaken, and individuals were assessed for lead (blood samples), and
for mercury (urine and hair samples). River water samples had high concentrations of particulate matter (700 mg/L). Mercury
and lead levels in water at the gold processing plants were very high in both seasons (250 ng Hg/L and 160 μg Pb/L). Mercury
and lead, there was a downstream gradient with the areas adjacent to the gold processing plants having the highest levels.
In Portovelo, the Upper Basin city, 14% of the population reported occupational exposure to inorganic mercury. Although no
one in Portovelo consumes water from the river, 10% of the population consume local fish. This contrasts the Lower Basin where
98% of the population consume fish, and 100% use river water for drinking and cooking. Lead blood levels over 20 μg/dl were
found in 39.4% of the study population and blood mercury over 10 μg/L only in 10.0%. Urinary mercury over 4 μg/L was found
in 66.5% of the examined persons. Hair methylmercury did not exceed the safe limit of 2 μg/g, the mean concentration was 1.2 μg/g.
Mining activity and erosion contributes to heavy-metal contamination (mercury, lead, and manganese) throughout the Puyango
Basin. The relation between environmental contamination is complex and further research is being conducted to understand these
relations. 相似文献
6.
The tissue bank “Rosa Guerzoni Chambergo” (RGCTB) located at the Child’s Health Institute was inaugurated in 1996, with the
financial and technical support of the IAEA program on radiation and tissue banking. Since 1998, the biological bandage of
fresh and lyophilised pigskin, amnion and bone tissue is processed routinely in this bank. In all cases, the tissue is sterilised
with the use of Cobalt-60 radiation, process carried out at the Laboratories of Irradiation of the Peruvian Institute of Nuclear
Energy (IPEN). The tissue bank in the Child’s Health Institute helped to save lives in an accident occurred in Lima, when
a New Year’s fireworks celebration ran out of control in January 2002. Nearly 300 people died in the tragic blaze and hundreds
more were seriously burned and injured. Eight Lima hospitals and clinics suddenly were faced with saving the lives of severely
burned men, women and children. Fortunately, authorities were ready to respond to the emergency. More than 1,600 dressings
were sterilised and supplied to Lima surgeons. The efforts helped save the lives of patients who otherwise might not have
survived the Lima fire. Between 1998 and September 2007, 35,012 tissue grafts were produced and irradiated. Radiation sterilised
tissues are used by 20 national medical institutions as well as 17 private health institutions. The tissue bank established
in Peru with the support of the IAEA is now producing the following tissues: pigskin dressings, fresh and freeze-dried; bone
allografts, chips, wedges and powdered, and amnion dressings air-dried. It is also now leading the elaboration of national
standards, assignment being entrusted by ONDT (Organización Nacional de Donación y Transplantes; National Organisation on
Donation and Transplant). This among other will permit the accreditation of the tissue bank. In this task is also participating
IPEN. 相似文献
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Carolin R Loescher Tobias Gro?kopf Falguni D Desai Diana Gill Harald Schunck Peter L Croot Christian Schlosser Sven C Neulinger Nicole Pinnow Gaute Lavik Marcel M M Kuypers Julie LaRoche Ruth A Schmitz 《The ISME journal》2014,8(11):2180-2192
Nitrogen fixation, the biological reduction of dinitrogen gas (N2) to ammonium (NH4+), is quantitatively the most important external source of new nitrogen (N) to the open ocean. Classically, the ecological niche of oceanic N2 fixers (diazotrophs) is ascribed to tropical oligotrophic surface waters, often depleted in fixed N, with a diazotrophic community dominated by cyanobacteria. Although this applies for large areas of the ocean, biogeochemical models and phylogenetic studies suggest that the oceanic diazotrophic niche may be much broader than previously considered, resulting in major implications for the global N-budget. Here, we report on the composition, distribution and abundance of nifH, the functional gene marker for N2 fixation. Our results show the presence of eight clades of diazotrophs in the oxygen minimum zone (OMZ) off Peru. Although proteobacterial clades dominated overall, two clusters affiliated to spirochaeta and archaea were identified. N2 fixation was detected within OMZ waters and was stimulated by the addition of organic carbon sources supporting the view that non-phototrophic diazotrophs were actively fixing dinitrogen. The observed co-occurrence of key functional genes for N2 fixation, nitrification, anammox and denitrification suggests that a close spatial coupling of N-input and N-loss processes exists in the OMZ off Peru. The wide distribution of diazotrophs throughout the water column adds to the emerging view that the habitat of marine diazotrophs can be extended to low oxygen/high nitrate areas. Furthermore, our statistical analysis suggests that NO2− and PO43− are the major factors affecting diazotrophic distribution throughout the OMZ. In view of the predicted increase in ocean deoxygenation resulting from global warming, our findings indicate that the importance of OMZs as niches for N2 fixation may increase in the future. 相似文献
10.
The idea that cohesive groups, in which individuals help each other, have a competitive advantage over groups composed of selfish individuals has been widely suggested as an explanation for the evolution of cooperation in humans. Recent theoretical models propose the coevolution of parochial altruism and intergroup conflict, when in-group altruism and out-group hostility contribute to the group''s success in these conflicts. However, the few empirical attempts to test this hypothesis do not use natural groups and conflate measures of in-group and unbiased cooperative behaviour. We conducted field experiments based on naturalistic measures of cooperation (school/charity donations and lost letters'' returns) with two religious groups with an on-going history of conflict—Catholics and Protestants in Northern Ireland. Conflict was associated with reduced donations to out-group schools and the return of out-group letters, but we found no evidence that it influences in-group cooperation. Rather, socio-economic status was the major determinant of cooperative behaviour. Our study presents a challenge to dominant perspectives on the origins of human cooperation, and has implications for initiatives aiming to promote conflict resolution and social cohesion. 相似文献
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We review the key determinants of health in Ucayali, Peru, identified by researchers, and, according to these, propose a set of tools to improve health in this area. Women and indigenous peoples are recognized as two vulnerable groups in the region that face greater health risks, and these are the main focus of the development of tools for health improvement. Also, the growing economic integration in the region facilitates the spread of infectious disease, thus requiring several levels of intervention. The tools discussed to improve health in Ucayali cross several scales and sectors. They include improved natural resource management, education and empowerment of women, integration of traditional and biomedical care, improved health information management, and community mobilization for health. Overall, our conclusions reinforce the limitations of the biomedical approach, which focuses on the treatment of specific pathologies in improving health. Health-system development requires the cooperation of many sectors and many actors across several spatial scales. 相似文献
15.
STUART KIRSCH 《American anthropologist》2008,110(3):288-298
ABSTRACT In this article, I explore what a critical environmental perspective would look like in Melanesia, where the distinction between nature and culture, and the expectation that science interprets the former in terms of the latter, may not apply. I consider changes in scientific knowledge production and the shift from cultural ecology to political ecology in Melanesian anthropology, including the argument that Melanesians are neither conservationists nor environmentalists. In contrast, I show how people exposed to pollution from the Ok Tedi copper and gold mine in Papua New Guinea mobilize their understandings of difference in a green critique of capitalism. I examine a strategy session of local activists, a public meeting about their campaign against the mine, and a sorcery tribunal. Finally, I suggest that Melanesian ideas about social relations provide a useful ethnographic analogy for thinking about the mobility and short temporal horizons of contemporary capitalism. 相似文献
16.
《Journal of Industrial Ecology》2004,8(1-2):11-21
Land use is an increasingly important component of sustainability evaluations, and numerous performance metrics have evolved to meet this need. The selection of appropriate land-use metrics for decision makers, however, remains an ongoing challenge. Additionally, life-cycle practitioners often struggle to provide meaningful impact assessment because of challenges associated with traditional land-use impact metrics. This article is intended to assist decision makers and life-cycle practitioners who wish to more effectively measure and evaluate one aspect of land use: surface area occupation. Existing performance metrics are discussed, and the specific circumstances under which each is appropriate are identified. Building on leading-edge research and analysis in the field of life-cycle impact assessment, a modified methodology for evaluating surface area occupation is proposed. This approach is demonstrated for a series of mining practices including three individual gold mines, a bauxite mine, and a copper mine. The specific data requirements and resulting equivalency factors for each mine are discussed. Results indicate that equivalency factors for gold (average of 700 acre-yr/ton) are expected to be several orders of magnitude higher than for either bauxite (0.004 acre-yr/ ton) or copper (0.03 acre-yr/ton). These dramatic differences in results demonstrate that equivalency factors are appropriate and necessary for including land-use impact potential as part of a life-cycle assessment that includes several different minerals or material requirements. 相似文献
17.
Karen A. Alroy Christine Huang Robert H. Gilman Victor R. Quispe-Machaca Morgan A. Marks Jenny Ancca-Juarez Miranda Hillyard Manuela Verastegui Gerardo Sanchez Lilia Cabrera Elisa Vidal Erica M. W. Billig Vitaliano A. Cama César Náquira Caryn Bern Michael Z. Levy Working Group on Chagas Disease in Peru 《PLoS neglected tropical diseases》2015,9(7)
18.
Olia V. Karnachuk Nikolay V. Pimenov Sandjar K. Yusupov Yulia A. Frank Yulia A. Frank Anna H. Kaksonen 《Geomicrobiology journal》2013,30(1-2):11-25
Abstract The purpose of this study was to characterize the distribution and activity of sulfate-reducing bacteria in tailings and sediments impacted by effluents from mining and smelting operations in the Norilsk area in northern Siberia. The Norilsk mining complex involves three smelter operations, a hydrometallurgical plant, and extensive tailings areas located in the permafrost zone. Sulfate reduction rates measured with a 35SO4 2? tracer technique under various in-situ conditions ranged from 0.05 to 30 nmol S cm?3 day?1. Acetate and glucose addition greatly stimulated sulfate reduction, whereas lactate had less effect. The most pronounced stimulation of sulfate reduction (6.5-fold) was observed with phosphate amendment. Most-probable-number (MPN) counts of sulfate-reducing bacteria in media with glucose, ethanol, lactate, and acetate as electron donors were generally highest at around 107 cells ml?1. The actual MPN counts varied with the sample, electron donor, and incubation conditions (pH 7.2 vs. pH 3.5; 28°C vs. 4°C). Enrichment cultures of sulfate-reducing bacteria were established from a sample that showed the highest rate of sulfate reduction. After multiple serial transfers, the dominant sulfate-reducers were identified by fluorescence in situ hybridization using genus and group-specific 16S rRNA-targeted oligonucleotide probes. Desulfobulbus spp. prevailed in ethanol and lactate enrichments and the Desulfosarcina-Desulfococcus group dominated in acetate and benzoate enrichments. Psychrophilic Desulfotalea-Desulfofustis and moderately psychrophilic Desulforhopalus spp. were identified in enrichments incubated at 4°C, but they were also found in mesophilic enrichments. 相似文献
19.
Zhang D Arevalo-Gardini E Mischke S Zúñiga-Cernades L Barreto-Chavez A Del Aguila JA 《Annals of botany》2006,98(3):647-655
BACKGROUND AND AIMS: Cocoa (Theobroma cacao) is indigenous to the Amazon region of South America, and it is well known that the Peruvian Amazon harbours a large number of diverse cocoa populations. A small fraction of the diversity has been collected and maintained as an ex-situ germplasm repository in Peru. However, incorrect labelling of accessions and lack of information on genetic diversity have hindered efficient conservation and use of this germplasm. This study targeted assessment of genetic diversity and population structure in a managed and a semi-natural population. METHODS: Using a capillary electrophoresis genotyping system, 105 cocoa accessions collected from the Huallaga and Ucayali valleys of Peru were fingerprinted. Based on 15 loci SSR profiles, genetic identity was examined for each accession and duplicates identified, population structure assessed and genetic diversity analysed in these two populations. KEY RESULTS: Ten synonymous mislabelled groups were identified among the 105 accessions. The germplasm group in the Huallaga valley was clearly separated from the group in Ucayali valley by the Bayesian assignment test. The Huallaga group has lower genetic diversity, both in terms of allelic richness and of gene diversity, than the Ucayali group. Analysis of molecular variance suggested genetic substructure in the Ucayali group. Significant spatial correlation between genetic distance and geographical distances was detected in the Ucayali group by Mantel tests. CONCLUSIONS: These results substantiate the hypothesis that the Peruvian Amazon hosts a high level of cocoa genetic diversity, and the diversity has a spatial structure. The introduction of exotic seed populations into the Peruvian Amazon is changing the cocoa germplasm spectrum in this region. The spatial structure of cocoa diversity recorded here highlights the need for additional collecting and conservation measures for natural and semi-natural cocoa populations. 相似文献
20.
Alvarado M 《ZooKeys》2012,(163):83-90
The genus Meggoleus Townes, 1971 (Ichneumonidae, Tersilochinae) currently comprises two species, one from Brazil and one from Gabon. The genus is recorded from Peru for the first time, with a range extension of the type species, Meggoleus spirator Townes, 1971, and the discovery of two new species - Meggoleus fuscatussp. n. and Meggoleus pampahermosensissp. n. A key to the world's species is provided. 相似文献