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Length-Weight Relationships and Condition Factors of 15 Fish Species from the Loémé River Basin (Mayombe, Republic of Congo)

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Open Journal of Ecology 2023年第12期13卷 883-893页

作者： Honest Freedom Poaty Ngot Victor Mamonekene Armel Ibala Zamba Leendert Van Den Berg César Ngoulou dabney matoko kouediatouka Aulne Lérège Batiabo Mikembi Hélène Dembe Louvinguila Tenda Institut National de Recherche en Sciences Exactes et Naturelles IRSEN Brazzaville République du Congo Faculté de Sciences et Techniques (FST) Université Marien Ngouabi Brazzaville République du Congo Ecole Nationale Supérieure Agronomie et de Foresterie (ENSAF) Université Marien Ngouabi Brazzaville République du Congo Institut Nationale de Recherche Agronomique (IRA) Brazzaville République du Congo Groupe Van den Berg Project Management B.V. Utrecht Netherlands Centre National d’Inventaire et d’Aménagement des Ressources Forestières et Fauniques (CIARF) Brazzaville République du Congo

Length-weight relationships and condition factors are among the commonly used parameters to link the length of a fish to its weight. The present study was initiated to find out the growth patterns and overweight status of 15 fish species in the Loémé basin in Mayombe, Republic of Congo. In the period from February 2020 to September 2021, sampling was carried out in eight stations, following a standardised capture method using four gillnets of 10, 12, 15, and 25 mm mesh size and a hawk net of 1.90 m radius with 10 mm mesh size. Length-weight relationships were calculated according to P = aLSb and the condition factor, using K = (P/LSb)* 100. A total of 1153 specimens representing 15 species, 10 genera and 6 families were recorded. The number of specimens ranged from 10 to 214 for Chrysichthys auratus and Enteromius camptacanthus, respectively. The allometry coefficient b minimum of 2.697 for Chromidotilapiamelaniae and maximum of 3.589 for Garraornata, with a mean of 3.03 ± 0.2 is significantly not different from 3 at the 0.05 probability threshold and indicates isometric growth for almost all species, except for E. camptacanthus where b = 2.858 was statistically different from 3 at the same threshold. The positive and high values of the coefficients of determination r2 = 0.787-0.989 of the species, obtained during this study, suggest that weight increases with size in the fish of the Loémé basin. The average condition factor varies from 0.524 ± 0.064 for G. ornata to 4.917 ± 0.440 for C. melaniae.

关键词： Fish Growth Overweight Loémé River Basin Lower Guinea

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特别的回报方式

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疯狂英语（新策略） 2018年第9期 30-31,64页

作者： dabney 白玲

语篇导读美国男孩贾斯汀的腿意外骨折,当地一家非盈利儿童医院将他的腿治愈。这个善良又聪明的小男孩设计出了一个独特的计划报答这家医院。他用抽奖券的形式卖掉自家的牛肉,把钱捐给需要治疗的孩子。你是不是想尽快了解一下这个名副其... 详细信息

语篇导读美国男孩贾斯汀的腿意外骨折,当地一家非盈利儿童医院将他的腿治愈。这个善良又聪明的小男孩设计出了一个独特的计划报答这家医院。他用抽奖券的形式卖掉自家的牛肉,把钱捐给需要治疗的孩子。你是不是想尽快了解一下这个名副其实的小牛仔呢？

关键词：回报男孩医院

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Examining the Digital Story Created by an Adolescent with Cancer: Insights and Ideas from a Case Story

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Open Journal of Nursing 2016年第5期6卷 426-434页

作者： dabney K. Wilson Sadie P. Hutson Joanne M. Hall Kim M. Anderson College of Nursing University of Tennessee Knoxville USA

Digital Storytelling (DST) has been recognized as a holistic and innovative storytelling avenue. Survival rates for pediatric oncology patients are improved, making it necessary to investigate the psychosocial perspectives of these children. This research began following a comprehensive review of the scientific literature and identification of a gap as it pertains to using DST as an avenue for acquiring data about this aggregate of patients. The purpose of this project was to explore the use of DST among pediatric cancer patients and their perspectives regarding diagnosis. We employed a qualitative case study design with two oncology patients between the ages of 11 - 17 years. The narrative, digital story, and field notes comprise the qualitative data. DST narratives and field notes were analyzed using qualitative content analysis to extract themes. Findings will provide the foundation for future research to explore the use of DST as both an intervention and data collection method in this population.

关键词： Digital Storytelling Adolescent Cancer Development Quality of Life

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Changes in Chemical Composition of Soluble Organic Chemical Compounds during Litters Decomposition into Tropical Forest of Milletia laurentii De Wild

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Open Journal of Forestry 2019年第1期9卷 70-87页

作者： Gouolaly Tsiba Mavoungou Naiving Flovique Rosère Edzonga Josianne Milandou matoko Jodhry Préféré Malonga Urielle Marini Madingou Parfait Noé Binsangou Stoffenne Ifo Suspense Averti National Institute for Research in Health Science Department of Pharmacopeia and Folk Medicine ChemistryOrganic Biomolecules and Pharmacodynamics LaboratoryBrazzavilleRepublic of Congo Sciences and Technologies Faculty Marien Ngouabi UniversityBrazzavilleRepublic of Congo LGETA ENSMarien Ngouabi UniversityBrazzavilleRepublic of Congo ENSAF Marien Ngouabi UniversityBrazzavilleRepublic of Congo

Recent publication attested that in the urban forest of Brazzaville, litter decomposition is faster with almost 45% of initial weight loss than in the dry season, where an average loss of 26% in initial litter weight is noted (Ifo et al., 2018). This study was carried out in the urban forest of Brazzaville to follow the decomposition of some organic compounds/secondary metabolites (reducing Sugars, total Flavonoid and Polyphenols) of the leaves litters of two tropical species Antiaris toxicaria Lesch and Millettia laurentii De Wild. Thin-layer chromatography and spectrophotometric assay of these metabolites were used on the samples of litters collected in the field on various dates of follow-up of the decomposition (0 d, 14 d, 28 d, 42 d, 56 d, 72 d and 84 d). The chromatographic profile of initial litters shows a series of spots on yellow florescence materializing presence of flavonoids, green fluorescence revealing the presence of the acids phenols derived from the cinnamic acid. But the chromatographic profile of the two litters in decomposition after two weeks remains without structural information, being able to characterize the decomposition of the chemical families highlighted in the initial litters. Also, the analysis of quantitative total reducing sugar in the initial litters, gives average concentrations of 64.4, 58.6, 57.5 g EG/kg Ms respectively for the litters of Millettia laurentii De Wild, Antiaris toxicaria Lesch and the mixed litters (Millettia laurentii and Antiaris toxicaria). Comparatively with the other types of litters, the initial average concentrations in phenolic compounds (polyphenols and flavonoids totals) were the highest for the litters of Antiaris toxicaria Lesch (27.3 g EAG/kg Ms and 13.07 g EC/kg Ms) (P = 0.001). The losses of organic chemical compounds are more significant during the first two weeks of experiment than after this period. Antiaris toxicaria Lesch loses on average 43.8 g EG/kg Ms of reducing Sugars, 12.21 g EC/kg Ms of

关键词： Tropical Urban Forest Litter Decomposition Organic Chemical Compounds

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Effect of Terrestrial LiDAR Point Sampling Density in Ephemeral Gully Characterization

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Open Journal of Modern Hydrology 2013年第1期3卷 38-49页

作者： Henrique G. Momm Ronald L. Bingner Robert R. Wells Seth M. dabney Lyle D. Frees Department of Geosciences Middle Tennessee State University Murfreesboro USA National Sedimentation Laboratory United States Department of Agriculture—Agricultural Research Service Oxford USA United States Department of Agriculture—Natural Resources Conservation Service Salina USA

Gully erosion can account for significant volumes of sediment exiting agricultural landscapes, but is difficult to monitor and quantify its evolution with traditional surveying technology. Scientific investigations of gullies depend on accurate and detailed topographic information to understand and evaluate the complex interactions between field topography and gully evolution. Detailed terrain representations can be produced by new technologies such as terrestrial LiDAR systems. These systems are capable of collecting information with a wide range of ground point sampling densities as a result of operator controlled factors. Increasing point density results in richer datasets at a cost of increased time needed to complete field surveys. In large research watersheds, with hundreds of sites being monitored, data collection can become costly and time consuming. In this study, the effect of point sampling density on the capability to collect topographic information was investigated at individual gully scale. This was performed through the utilization of semi-variograms to produce overall guiding principles for multi-temporal gully surveys based on various levels of laser sampling points and relief variation (low, moderate, and high). Results indicated the existence of a point sampling density threshold that produces little or no additional topographic information when exceeded. A reduced dataset was created using the density thresholds and compared to the original dataset with no major discrepancy. Although variations in relief and soil roughness can lead to different point sampling density requirements, the outcome of this study serves as practical guidance for future field surveys of gully evolution and erosion.

关键词： Ephemeral Gully Ground-Based LiDAR Soil Erosion Point Sampling Density Remote Sensing

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CONTROL OF GULLY EROSION USING STIFF GRASSES

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International Journal of Sediment Research 2005年第4期20卷 319-332页

作者： F. D. SHIELDS, Jr. S. M. dabney E. J. LANGENDOEN D. M. TEMPLE Research Hydraulic Engineer USDA-ARS National Sedimentation Laboratory Oxford Mississippi Research Argonomist USDA-ARS National Sedimentation Laboratory Oxford Mississippis Research Hydraulic Engineer USDA-ARS National Sedimentation Laboratory Oxford Mississippi USDA-ARS Hydraulic Engineering Research Unit Stillwater

Concentrated flow can cause gully formation on sloping lands and in riparian zones. Current practice for riparian gully erosion control involves blocking the gully with a structure comprised of an earthen embankment and a metal or plastic pipe. Measures involving native vegetation would be more attractive for habitat recovery and economic reasons. To test the hypothesis that switchgrass (Panicum virgatum L.) hedges planted at 0.5-m vertical intervals within a gully would control erosion, a series of hedges was established in four concentrated flow channels. Two of the channels were previously eroded trapezoidal channels cut into compacted fill in an outdoor laboratory. The other two channels were natural gullies located at the edge of floodplain fields adjacent to an incised stream. While vegetation was dormant, artificial runoff events were created in the two laboratory gullies and one of the natural gullies using synthetic trapezoidal-shaped hydrographs with peak discharge rates of approximately 0.03, 0.07, and 0.16 m3/s. During these tests flow depth, velocity, turbidity, and soil pore water pressures were monitored. The fourth gully was subjected to a series of natural runoff events over a five-month period with peaks up to 0.09 m3/s. Flow depths in all tests were generally 1 for step heights 1 m, consistent with the experimental observations.

关键词： Erosion Gully Grass hedges Buffers

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USDA-ARS National Sedimentation Laboratory:A Historic Perspective

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Journal of Water Resource and Protection 2015年第3期7卷 228-246页

作者： Robert R.Wells Sean J.Bennett Ronald L.Bingner Seth M.dabney Eddy J.Langendoen Henrigue G.Momm Mathias J.M.Romkens Glenn V.Wilson Agricultural Research Service United States Department of AgricultureOxfordUSA Department of Geography University at BuffaloBuffaloUSA Department of Geosciences Middle Tennessee State UniversityMurfreesboroUSA

Most authorities concede sediment from soil erosion to be the largest single stream pollutant. Physical damage from sediment includes reservoir storage loss, navigation channel filling, stream channel morphology alterations, ecological impacts, and clogging of drainage pathways. Ultimately, soil erosion is a very expensive problem. In the United States, accelerated soil erosion has been an ongoing issue since the establishment of the colonies. Through the initiative of great minds and the labor of countless individuals, the USDA was established and continues to fight for the people, providing assistance, guidance, and research. In this manuscript, the historical groundwork is laid for the establishment of the USDA-ARS National Sedimentation Laboratory (NSL) and a synopsis of NSL research is provided. This brief perspective of soil erosion research conducted on behalf of the people is but a small portion of the illustrious history of the USDA.

关键词： Soil Erosion Sedimentation Ephemeral Gully Water Quality Modeling

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MANAGEMENT AND SUBSURFACE EFFECTS ON RUNOFFAND SEDIMENT YIELD FROM SMALL WATERSHEDS

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International Journal of Sediment Research 2000年第2期 217-232页

作者： dabney, S. M. L. D. Meyer C. E. Murphree( USDA-ARS, National Sedimentation Laboratory, Oxford, MS, USA)R. L. Raper(USDA-ARS, National Soil Dynamics Laboratory, Aubum, AL, USA)

Research on erosion plots and small watersheds with upland loessal soils containing hydraulically-controlling subsurface horizons showed that as scale increases so does the amount ofarmual runoff Theamount of runoff from 2 to 3 ha watersheds was twice that from 0.008 ha plots. However, the ratio ofrunoff from watersheds to plots was 3.0 from Dec through March, and only 1 .7 during the rest of the *** penetrometer resistance measurements documented the presence of restrictive layers within1 m of the soil surface. Observation wells showed the presence of spatially varying perched water *** propose that the runoff difference between plot and watershed scales was re1ated to the increasingimportance of hydraulically restrictive subsurface horizons, especially during the winter months. Waterinfiltrated into linear backslope areas that the plots represent may converge in concave toe slopes areas,creating wetter antecedent conditions and return flow contributions to surface runoff No-tillmanagement reduced sediment production by about 90% on plots and by at least 95% on watersheds; notill reduced runoff about 10% from both plots and watersheds in this study. Conservation managementaffected hydraulic resistance at the soil surface rather than the permeability of deep restrictive layers.

关键词： Erosion plot No-till management Conservation management Runoff Sediment yield

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