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Field management of Taro (Colocasia esculenta (L.) Schott) leaf blight via fungicidal spray of foliage 芋的田间管理通过叶片的杀真菌喷雾来防治叶枯萎病
Pub Date : 2021-04-19 DOI: 10.4314/JCAS.V16I3.2
T. Mbi, Godswill Ntsomboh-Ntsefong, L. B. Tonfack, E. Youmbi
Taro leaf blight (TLB) epidemic hit Cameroon for the first time in 2009. Since then, the disease is persistent and its typical devastating legacy is threatening Taro (Colocasia esculenta) in the North and South West Regions of Cameroon. This study was initiated with the objective to determine the potentials of some fungicides to control TLB. The experimental design was completely randomized with a 3x15x2 factorial, including 3 treatments: T1 (Callomil plus72WP), T2 (Mancoxyl plus 720WP) and T3, 1:1 ratio T1 + T2 all applied at concentrations of 4g/L; 15 repetitions and 2 planting seasons (dry season i.e. October 2014 – March 2015 and rainy season i.e. April-October 2015). Disease incidence and disease severity were used to evaluate the disease progression while corm yield was used to appraise the economic injury. The results revealed disease incidence of 0% during the dry season and 18.2%, 27.3% and 100%, for T1, T2 and T3 and control during rainy season respectively. Disease severity was 75% in control and only 1% for the different treatments. Corm yield in the rainy season was 17.4kg, 15.08kg, 14.27kg and 5.89kg for T1, T2, T3 and control respectively. This study suggests that TLB epidemic can effectively be managed by foliage spray with Metalaxyl containing fungicides at a weekly dosage of 4g/ L.
芋头叶枯病(TLB)于2009年首次袭击喀麦隆。自那时以来,该疾病持续存在,其典型的破坏性遗产正在威胁喀麦隆北部和西南地区的芋头。本研究的目的是确定一些杀菌剂控制TLB的潜力。试验设计采用3x15x2因子完全随机化设计,包括3个处理:T1(卡罗密加72wp)、T2(曼可赛特加720WP)和T3(1:1比例T1 + T2),浓度均为4g/L;15次重复,2个种植季节(旱季即2014年10月- 2015年3月,雨季即2015年4月- 10月)。以发病率和严重程度评价病害进展,以玉米产量评价经济危害。结果显示,旱季发病率为0%,雨季T1、T2和T3与对照分别为18.2%、27.3%和100%。对照组的疾病严重程度为75%,而不同治疗组仅为1%。雨季玉米产量T1、T2、T3和对照分别为17.4kg、15.08kg、14.27kg和5.89kg。本研究表明,含甲螨灵的杀菌剂每周喷施4g/ L,可有效控制TLB的流行。
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引用次数: 3
Comparative effects of charred bamboo and its ash on the growth of Entandrophragma angolense (welw.) C dc seedlings 竹炭与竹炭灰对安哥拉青竹生长的比较研究直流电苗
Pub Date : 2021-04-19 DOI: 10.4314/JCAS.V16I3.1
A. Aderounmu, I. Asinwa, J. O. Omolewa, J. Ishola
Entandrophragma angolense is relatively slow growing species and its growth needs to be enhanced by soil nutrients amendment. Uniformed two weeks old seedlings of E. angolense were transplanted into the polythene pots filled with 2kg of degraded soil and mixed with different levels of biochar and ash produced from bamboo. A 2 x 7 factorial experiment was laid out in Completely Randomized Design (CRD) with four replications to assess the effects of charred bamboo and its ash on the stem girth, leaf area, leaf production and shoot height of E. angolense. The germination data were subjected to descriptive statistics and analysis of variance (ANOVA). There were significant differences (p<0.05) among the treatments in leaf area and shoot height while there were no significant differences (p>0.05) among the treatments in stem girth, leaf production and interactions among levels of biochar and ash. On stem girth, leaf production and shoot height, T6 (15g of bio char + 15g of ash + degraded soil) had the highest mean value of 4.27 mm, 4.59 and 37.55cm respectively while T2 (30g of bio char + 0g of ash + degraded soil) had the highest leaf area (73.31cm2). The biochar and ash from bamboo had significant effects on the growth and development of E. angolense seedlings on degraded soil.
安哥拉穿山甲是一种生长较慢的植物,需要通过土壤养分的改良来促进其生长。将两周大、形状一致的安哥拉棘猴幼苗移栽到装满2公斤退化土壤的聚乙烯盆中,并与不同水平的生物炭和竹灰混合。采用完全随机设计(CRD),采用2 × 7因子试验,4个重复评价焦化竹及其灰分对青松茎周长、叶面积、叶片产量和茎高的影响。发芽数据进行描述性统计和方差分析(ANOVA)。在茎周长、叶片产量以及生物炭和灰分水平的相互作用方面,各处理间存在显著差异(p0.05)。在茎长、叶片产量和茎高方面,T6 (15g生物炭+ 15g灰分+退化土)的平均值最高,分别为4.27 mm、4.59和37.55cm, T2 (30g生物炭+ 0g灰分+退化土)的叶面积最高,为73.31cm2。在退化土壤中,竹炭和竹灰对青松幼苗的生长发育有显著影响。
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引用次数: 1
The utilisation of satellite imagery and community perceptions to assess the impacts of sea encroachment in the West Coast of Cameroon at Limbe 利用卫星图像和社区感知来评估喀麦隆西海岸林贝海域海洋侵蚀的影响
Pub Date : 2021-04-19 DOI: 10.4314/JCAS.V16I3.3
M. Wantim, Wase Albright Mokosa, Louis Jitiz, S. Ayonghe
Coastal erosion associated to sea encroachment is a major problem at the West Coast of Limbe, specifically in the Debundscha Fishing Port (DFP). This study sought to assess the physical vulnerability of the West Coast of Limbe to coastal erosion associated to sea encroachment. This was achieved by assessing: i) the physical vulnerability of the West Coast to coastal erosion; ii) land cover changes and iii) community perception at DFP to sea encroachment and coastal erosion in the past 30 years. Three variables: rock type, adjacent land use and coastal protection were used to assess the vulnerability of the West Coast to coastal erosion. Landcover / coastal changes were assessed from satellite images from 1986 to 2018. Semi-structural interviews were used to acquire knowledge on the population’s perception and impact of the studied hazards. A cost benefit approach was used to weigh the potentials of these localities to adapt to coastal erosion. The DFP and Idenau Beach were identified as major hotspots of coastal erosion with an annual rate of >100 m2. Landcover changes showed a net increase in water levels inland and into settlements. The population is knowledgeable and is aware of the risk of sea encroachment and coastal erosion. The physical, socio-economic and health effects were: destruction of mangroves; relocation; malaria, typhoid and abdominal illnesses respectively. Coping strategies included the use of sandbags, building on higher grounds and on embankments. Cost benefit analysis ranked vegetative cover as the best option environmentally and financially viable to reduce coastal erosion from sea encroachment at the West Coast.
与海洋侵蚀有关的海岸侵蚀是Limbe西海岸的一个主要问题,特别是在Debundscha渔港(DFP)。本研究旨在评估林贝西海岸对与海洋侵蚀相关的海岸侵蚀的物理脆弱性。这是通过评估:1)西海岸对海岸侵蚀的物理脆弱性;ii)过去30年的土地覆盖变化和iii) DFP社区对海洋侵蚀和海岸侵蚀的感知。采用岩石类型、邻近土地利用和海岸保护三个变量来评估西海岸对海岸侵蚀的脆弱性。根据1986年至2018年的卫星图像评估了土地覆盖/沿海变化。采用半结构式访谈来了解人们对所研究的危害的认知和影响。采用成本效益方法来衡量这些地方适应海岸侵蚀的潜力。DFP和Idenau海滩是主要的海岸侵蚀热点,年侵蚀速率大于100 m2。土地覆盖变化表明内陆和定居点的水位净增加。当地居民知识渊博,意识到海洋侵蚀和海岸侵蚀的风险。对自然、社会经济和健康的影响是:红树林遭到破坏;搬迁;分别是疟疾、伤寒和腹部疾病。应对策略包括使用沙袋,在较高的地面和堤防上建造。成本效益分析将植被覆盖列为环境和经济上可行的减少西海岸海洋侵蚀的最佳选择。
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引用次数: 1
Wildlife collections of Royal Palace Museums in The West Region of Cameroon with a Focus on wildlife conservation 喀麦隆西部地区皇家宫殿博物馆的野生动物收藏,重点是野生动物保护
Pub Date : 2021-04-19 DOI: 10.4314/JCAS.V16I3.5
Mohamed Mounir Mfonden Poumie, Peter Coals, F. Meutchieye, Olivier Miantsia Fokam
The royal palace museums of the Grassfields’ Kingdoms of West Region of Cameroon are well recognized for the preservation of culturally significant objects and practices. To date, the role of palace museums in wildlife conservation has received little consideration. Herein, a preliminary study into the animalbased artefacts of palace museums from a wildlife conservation perspective is presented. A total of 11 chiefdom palace museums in the West Region of Cameroon were surveyed and the animal species represented in their exhibitions recorded. Parts of 32 different animal species, including locally extinct large mammals such as lion, cheetah, chimpanzee, and elephant were found. The primary purpose for inclusion of specimens in palace museums was for preservation of culture. However, potential wildlife conservation focused uses to which palace museums may also put their collections are discussed herein.
喀麦隆西部格拉斯菲尔德王国的皇家宫殿博物馆以保存具有重要文化意义的物品和习俗而闻名。迄今为止,故宫在野生动物保护中的作用很少得到考虑。本文从野生动物保护的角度对故宫博物院的动物性文物进行了初步研究。对喀麦隆西部地区11个酋长宫殿博物馆进行了调查,并记录了其展览中所代表的动物物种。发现了32种不同动物的部分化石,包括当地灭绝的大型哺乳动物,如狮子、猎豹、黑猩猩和大象。故宫博物院收藏标本的主要目的是为了保存文化。然而,本文讨论了故宫博物院收藏的潜在野生动物保护重点用途。
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引用次数: 1
The thermal dehydroxylation of kaolinite using thermogravimetric analysis and Controlled rate thermal analysis 用热重分析法和控制速率热分析法研究高岭石的热脱羟基作用
Pub Date : 2021-04-19 DOI: 10.4314/JCAS.V16I3.4
J. Mbey, Cyrill Joël Ngally Sabouang, Thomas B. Makon, S. Coulibaly, Sakéo Kong
The aim of this work was to identify parameters that could influence the conversion of kaolinite into metakaolinite. To this end, the dehydroxylation of four kaolinites, using controlled rate thermal analysis (CRTA) and thermogravimetric analysis (TGA), was investigated. X-ray diffraction (XRD) and Fourier transform infra-red (FTIR) were used to confirm the kaolinitic nature of the samples. Their crystallinity was evaluated using the Hinckley index from the XRD patterns and transmission electron microscopy (TEM) was used for morphological observation of the clay platelets. The thermal analyses of the samples indicate, for all samples, low defects as revealed by the low amount of adsorbed water on the clay surface. The dehydroxylation temperature from both techniques was influenced by the sample crystallinity and particle size. It was observed from both techniques that increase crystallinity resulted in high dehydroxylation temperature. Also, the influence of the clay platelets size on the dehydroxylation temperature, is proposed. All the results indicate that crystallinity and particle size are parameters that could be used to control the temperature for the conversion of kaolinite to metakaolinite.
这项工作的目的是确定影响高岭石向偏高岭石转化的参数。为此,采用控制率热分析(CRTA)和热重分析(TGA)对四种高岭石的脱羟基化进行了研究。采用x射线衍射(XRD)和傅里叶红外(FTIR)对样品的高岭石性质进行了表征。利用x射线衍射(XRD)的欣克利指数(Hinckley index)对其结晶度进行了评价,并用透射电子显微镜(TEM)对其进行了形态学观察。样品的热分析表明,对于所有的样品,低缺陷,揭示了低量的吸附水在粘土表面。两种方法的脱羟基温度均受样品结晶度和粒径的影响。从两种技术中观察到,结晶度的增加导致脱羟基温度的升高。此外,还提出了粘土薄片大小对脱羟基温度的影响。结果表明,结晶度和粒度是控制高岭石向偏高岭石转化温度的重要参数。
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引用次数: 3
Impact of mineral and organic absorbent during the discoloration of avocado oil by comparing with olive oil 矿物和有机吸收剂对牛油果油与橄榄油变色的影响
Pub Date : 2021-01-27 DOI: 10.4314/JCAS.V16I2.4
O. Ngomo, J. Sieliechi, E. Dongo
Avocado is a versatile and valuable product. Its oil is comparable to olive oil in terms of nutritional quality. It can also be used in cosmetics, in particular, in soaps, shampoos and lotions. Despite all these important attributes that avocado has, it is highly perishable and coupled with the lack of farm-to-market roads, a lot of it is lost after harvest during the peak season. The introduction of methods that will transform avocado to products with a long shelf life and added value will go a long way to solving the problem of post-harvest losses and poverty. One of these methods is the production of avocado oil. In addition, in order to reduce the colour of the pigments without altering their quality, discoloration tests were carried out by adsorption on bleaching grounds (a montmorillonite, a kaolinite and activated carbon). The colour intensities of the oils before and after adsorption were determined using two complementary methods: a UV-Vis spectrophotometer and a Konica Minolta spectrophotometer CM-5. The UV-Vis spectrophotometer show that the activated carbon has a best fixing capacity of the pigments; According to the Colorimetric parameters (CIE-Lab) the coordinates L* a* b* that showed brightness (L*) of the avocado oil was half of the olive oil (41.13±0.02 vs 84.85±0.02). The activated carbon was better in fixing the red (a*) (4.99±0.01vs 15.73±0.01 before adsorption) and yellow (b*) (63.71±0.09 vs 70.07±0.09 before adsorption) pigments, while the other two adsorbents have very little influence on the red colour of avocado oil. ResumeL’avocat est un produit versatile et de grande valeur. Son huile est comparable a huile d’olive en terme de qualite nutritionnelle ; elle peut egalement etre utilisee en cosmetique en occurrence dans les savons, champoings et lotions. En pleine saison, l’on fait face a une abondance des avocats dans les zones de production qui sont tres souvent enclavees ; c’est ainsi que face aux difficultes de transport et les routes peu praticables pour l’importation, l’on se retrouve en train de perdre de tres importantes quantites d’avocats apres les recoltes. Or la production d’huile d’avocats permettrait de reduire les pertes post recolte, reduirait le chomage et permettrait de lutter contre la pauvrete apres la vente des huiles extraites. De plus, dans le but de reduire les pigments colores, des tests de decolorations effectues par adsorption sur des terres decolorantes (une montmorillonite en provenance de Maroua, une kaolinite en provenance de Douala et le charbon actif) sont effectues. Les couleurs des huiles mesurees avant et apres adsorption a l’aide deux appareils complementaires : Le spectrophotometre UV-Vis et du Konica Minolta spectrophotometre CM-5 montrent. Les analyses spectrophotometriques UV-Vis montrent que c’est le charbon active qui presente la meilleure adsorption des pigments ; D’apres les coordonnees L*a*b*, la clarte de l’huile d’avocat est pratiquement la moitie de celle de l’huile d’olive
鳄梨是一种用途广泛且有价值的产品。其油的营养质量可与橄榄油相媲美。它也可以用于化妆品,特别是肥皂、洗发水和乳液。尽管牛油果有这些重要的特性,但它很容易腐烂,再加上缺乏从农场到市场的道路,在收获后的旺季,很多牛油果都损失了。引入将牛油果转化为具有长保质期和附加值的产品的方法,将对解决收获后损失和贫困问题大有帮助。其中一种方法是生产鳄梨油。此外,为了减少色素的颜色而不改变其质量,通过在漂白基质(蒙脱石、高岭石和活性炭)上吸附进行了变色试验。采用紫外可见分光光度计和柯尼卡美能达分光光度计CM-5两种互补方法测定吸附前后油的颜色强度。紫外可见分光光度计测定表明,活性炭对颜料的固定能力最好;根据比色参数(CIE-Lab),显示牛油果油亮度(L*)的坐标L* a* b*为橄榄油的一半(41.13±0.02 vs 84.85±0.02)。活性炭对红色(a*)(4.99±0.01vs吸附前15.73±0.01)和黄色(b*)(63.71±0.09 vs吸附前70.07±0.09)色素的固定效果较好,而其他两种吸附剂对牛油果油的红色影响很小。简历是最重要的产品,多才多艺,价值巨大。儿子的蛋奶可比儿子的蛋奶营养丰富;在化妆品、香水、洗发水和乳液中都可以使用这些化妆品。在整个季节里,法国将面临大量的牛油果,而生产地区则会出现大量的牛油果。在运输上遇到困难,在进口上遇到困难,在运输上遇到困难,在进口上遇到困难,在运输上遇到困难,在运输上遇到困难,在运输上遇到困难,在运输上遇到困难。或者,在生产过程中,d ' ' avocat ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' '不加,不加,但不需要少量颜料的颜色,不加,不加,不加,不加,不加,不加,不加,不加,不加,不加,不加,不加,不加,不加,不加,不加。Les couleurs des huiles是一种紫外-可见分光光度计和柯尼卡美能达分光光度计CM-5检测器的互补装置。紫外-可见分光光度法测定活性炭活性组分,并对染料进行吸附;D 'apres les coordonnees L*a*b*, L ' hule le 'avocat est pratique la motie de le ' huole 'olive(41,13±0,02对照84,85±0,02),L ' huole 'avocat est pratique la motie de le ' huole 'olive(41,13±0,01对照15,73±0,01 avant吸附),le carbon active固定mieux les pigments rouges (a*)(63,71±0,09对照70,07±0,09 apres吸附),tandis que les deaux res吸附剂影响树胶在huiles上的着色。
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引用次数: 0
An assessment of the potability of groundwater from boreholes based on microbial quality and physical properties: case of Buea and Tiko Subdivisions, South West Region of Cameroon 基于微生物质量和物理性质对钻孔地下水可饮用性的评估:喀麦隆西南地区Buea和Tiko分区的案例
Pub Date : 2021-01-27 DOI: 10.4314/JCAS.V16I2.6
Helen Epouse Azise Ayimele, Melisa Bijingisi, S. Ayonghe
Groundwater from boreholes, though generally considered as potable water, is vulnerable to both microbial pollution and unsuitable physical characteristics. An assessment of the microbial quality and the physical properties of groundwater from boreholes was accordingly carried out in Buea and Tiko subdivisions to determine these parameters. In particular, the presence of coliform bacteria and an eventual isolation of E. coli and Salmonella spp which are faecal indicator organisms were carried out. A total of 46 samples were collected from 29 randomly selected boreholes and their physical parameters (temperature, pH, EC, TDS and turbidity), and microbial content analyzed. Physical parameters were measured in-situ using portable field devices while total coliform count and isolation of faecal coliforms (E. coli and Salmonella spp) were determined using standard microbiological methods with reagents, Violet Red Bile Agar, Mackonkey Agar and Salmonella Shigella Agar respectively. The results indicated that the physical characteristics of the water (pH range 4.9-8.4; EC range 90µS/cm-233µS/cm; TDS range 61 mg/L-1630 mg/L; Turbidity range 0.44NTU-59.80NTU) were within WHO guidelines for potability except for the turbidity with barely two samples that fell within the acceptable range of 1.5NTU. Total coliform counts ranged from 1x100CFU/ml to 3x103CFU/ml and 72.41% of the samples exceeded the WHO recommended 0.0 CFU/100 ml. E. coli was isolated in 76.47 % while Salmonella spp was isolated in 82.35% of the samples. This pioneer study on groundwater quality from boreholes in the study area reveals that the water is vulnerable to bacteriological pollution and therefore not potable. This necessitates awareness creation of the community on the regular disinfection of groundwater from boreholes. RESUMELes eaux souterraines des forages, bien que generalement considerees comme de l’eau potable, sont vulnerables a la fois a la pollution microbienne et a des caracteristiques physiques inappropriees. Une evaluation de la qualite microbienne et des proprietes physiques des eaux souterraines des forages a donc ete realisee dans les departements de Buea et Tiko pour determiner ces parametres. En particulier, la presence de bacteries coliformes et un eventuel isolement d’E. Coli et l’espece de Salmonella qui sont des organismes indicateurs de contamination fecale ont ete realises. Au total, 46 echantillons ont ete preleves dans 29 forages selectionnes au hasard et leurs parametres physiques (temperature, pH, CE, TDS et turbidite) et leur contenu microbien ont ete analyses. Les parametres physiques ont ete mesures sur place a l’aide d’appareils de terrain portables, tandis que le nombre total de coliformes et l’isolement des coliformes fecaux (E. coli et Salmonella spp) ont ete determines a l’aide de methodes microbiologiques standard avec des reactifs, la gelose violette rouge, la gelose Mackonkey et la gelose Salmonella Shigella respectivement. Les resultats ont ind
钻孔地下水虽然通常被认为是饮用水,但容易受到微生物污染和不适当的物理特性的影响。因此,在Buea和Tiko分区对钻孔地下水的微生物质量和物理性质进行了评估,以确定这些参数。特别是,大肠菌群的存在和最终分离大肠杆菌和沙门氏菌,这是粪便指示生物。随机选取29个钻孔共采集46份样品,分析其物理参数(温度、pH、EC、TDS和浊度)和微生物含量。采用便携式现场装置现场测量物理参数,采用标准微生物学方法测定粪便大肠菌群(大肠杆菌和沙门氏菌)总数,分别用紫红胆汁琼脂、麦孔基琼脂和志贺氏沙门氏菌琼脂试剂测定粪便大肠菌群(大肠杆菌和沙门氏菌)的分离。结果表明:水体物理特性(pH范围4.9 ~ 8.4;EC范围90µS/cm-233µS/cm;TDS范围61 mg/L-1630 mg/L;浊度范围0.44NTU-59.80NTU)在WHO指南的可饮用性范围内,除了只有两个样品的浊度落在1.5NTU的可接受范围内。大肠菌群总数在1 × 100cfu /ml ~ 3 × 103cfu /ml之间,72.41%的样品超过WHO推荐值0.0 CFU/100 ml,其中大肠杆菌和沙门氏菌分别占76.47%和82.35%。这项对研究区域钻孔地下水水质的开创性研究表明,水容易受到细菌污染,因此不适合饮用。这就需要提高社区对定期消毒钻孔地下水的认识。草料、草料、草料、草料、草料、草料、草料、草料、草料、草料、草料、草料、草料、草料、草料、草料、草料、草料、草料、草料、草料、草料、草料、草料、草料、草料、草料、草料、草料、草料、草料、草料、草料、草料、草料、草料、草料。《微生物质量评价》,《微生物质量评价》,《微生物质量评价》,《微生物质量评价》,《微生物质量评价》,《微生物质量评价》,《微生物质量评价》,《微生物质量评价》,《微生物质量评价》。特别是,细菌大肠菌群的存在最终导致了e的分离。大肠杆菌和沙门氏菌是污染粪便的主要微生物指标。总共有46个机制和29个饲料选择,包括温度、pH、CE、TDS和浊度等参数和微生物含量。这些参数的测定方法包括:地点测定法、地形测定法、便携式设备测定法、总大肠菌群测定法和分离大肠杆菌测定法、微生物学标准测定法、反应测定法、紫紫测定法、猕猴测定法和志贺氏沙门氏菌测定法。Les results ont inque que Les characteristicphysiques de l 'eau (plage de pH 4,9- 8,4;板材CE 90µS/cm-2330µS/cm;平板TDS 61 mg/L-1630 mg/L;浊积层0,44 ntu - 59.80NTU)的质量符合欧姆斯(l 'OMS)的标准。首尔,浊积岩等一种双机械装置,可满足15ntu的环境要求。1 × 100 CFU/ml、3 × 103 CFU/ml、72,41%、0 × 100 CFU/ml、0 × 100 CFU/ml推荐使用。大肠杆菌的分离值为76,47%,而沙门氏菌的分离值为82,35%。在南方的牧草区,在南方的牧草区,在南方的牧草区,在南方的牧草区,在南方的牧草区,在南方的牧草区,在南方的牧草区,在南方的牧草区,在南方的牧草区,在南方的牧草区,在南方的牧草区,在南方的牧草区,在南方的牧草区,在南方的牧草区,在南方的牧草区,在南方的牧草区,在南方的牧草区,最易受污染,最易受细菌的污染。在南方牧草的常规消毒中,有必要对社区消毒良心进行评估。
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引用次数: 1
Défis et enjeux de la gouvernance locale au Cameroun à l’ère de la décentralisation : cas de la ville de Garoua 喀麦隆地方分权时代地方治理的挑战和问题:以加鲁瓦市为例
Pub Date : 2021-01-27 DOI: 10.4314/JCAS.V16I2.7
Simon Pierre Petnga Nyamen
ResumeLe Decret N°2007/115 du 23 avril 2007 portant creation de nouveaux Arrondissements au sein de certains Departements du Cameroun traduit a priori la volonte du Gouvernement d’insuffler une dynamique nouvelle a son processus de decentralisation. A partir du cas de la ville de Garoua, ce travail traite des defis et enjeux de la gouvernance locale dans un contexte d’acceleration du processus de decentralisation en vue d’un developpement maitrise. Pour ce faire, des echanges avec vingt-six informateurs issus de l’administration publique et privee, douze chefs de quartier et trente des plus anciens habitants de Garoua ont ete mene. En plus, on a eu recours a une centaine d’informateurs et guides, qui ont permis de caracteriser trois cent cinquante-cinq marqueurs spatiaux de la dynamique urbaine de la localite. Les resultats de cette etude revelent que les defis et enjeux actuels de la gouvernance locale sont de trois ordres : reglementaire, financier et fonctionnel. Pour ce qui est du premier ordre, le probleme des villes camerounaises, est le non-respect de la reglementation en vigueur, et surtout l’omnipresence de la corruption. Le deuxieme ordre est celui de l’incapacite des municipalites a collecter les recettes ce qui ne limite leur investissement qu’a des ouvrages de tres faible impact social et economique. Sur le plan fonctionnel, la decentralisation a favorise la multiplication d’acteurs aux aspirations tres souvent divergentes, mais aussi une confusion voire une ignorance des roles. Au terme de cette etude, avec l’adoption de comportements legaux, il est recommande aux administrations locales de s’ouvrir au Systeme d’Information Geographique (SIG) qui dispose des methodes, techniques et outils permettant de gerer efficacement la donnee spatiale et par consequent le territoire. De plus, le processus de creation de ce systeme utilise pour la collecte, le stockage, l’analyse, la modelisation, la gestion, l’affichage et la representation de l’information spatiale, est une excellente aubaine pour la mise en oeuvre d’un cadre de concertation qui integre a differentes echelles, la representativite, les competences et les objectifs respectifs de toutes les parties prenantes a la gouvernance locale. AbstractDecree N°2007/115 of April 23, 2007 creating new subdivisions within some Divisions of Cameroon demonstrates the will of the Government to improve its decentralization process. Based on the case of the city of Garoua, this work deals with the challenges and issues of local governance, in a context of accelerating the decentralization process with a view to controlled development. To this end, exchanges with twenty-six informants from the public and private administration, twelve chiefdom leaders and thirty of the oldest inhabitants of Garoua were conducted. In addition, about one hundred informants and guides were used, who allowed to characterize three hundred and fifty-five spatial markers of the dynamics of the city. The results revealed t
2007年4月23日第2007/115号法令规定在喀麦隆某些部门设立新的区,这表明政府希望为其权力下放进程注入新的动力。本文以Garoua市为例,探讨了在加速权力下放进程以实现可控发展的背景下地方治理的挑战和问题。为此,与来自公共和私人行政部门的26名线人、12名区长和30名加鲁瓦最年长的居民进行了交流。此外,还聘请了大约100名线人和导游,他们帮助确定了355个当地城市动态的空间标志。研究结果表明,当前地方治理面临的挑战和问题有三个层次:监管、财务和功能。首先,喀麦隆城市面临的问题是不遵守现行法规,最重要的是腐败无处不在。第二,市政当局无法筹集收入,这限制了他们对社会和经济影响非常小的项目的投资。从功能的角度来看,权力下放a促进了利益相关者的扩散,这些利益相关者往往有着截然不同的愿望,但也导致了角色的混乱甚至无知。在本研究结束时,随着法律行为的采用,建议地方政府向地理信息系统(gis)开放,该系统拥有有效管理空间数据和领土的方法、技术和工具。此外,换挡过程创建这个用来收集、储存、分析、建模、管理、信息显示屏和代表权的空间来说,是一次很好的执行不同的协商框架的集成了梯子、代表性、技能和所有利益攸关方的各自的目标了地方治理。2007年4月23日第2007/115号法令在喀麦隆一些司内设立新的分区,表明政府愿意改进其权力下放进程。本工作以加鲁瓦市为例,在加速权力下放进程的背景下处理地方治理的挑战和问题,以控制发展。为此,与来自公共和私人行政部门的26名线人、12名首席领导人和加鲁瓦的30名最年长的居民进行了交流。= =地理= =根据美国人口普查,该县的土地面积为,其中土地面积为。结果表明,目前地方治理面临的挑战和问题有三个方面:监管、财务和职能。至于前者,喀麦隆城市面临的问题是不遵守现行条例,特别是普遍存在腐败现象。第二种秩序是市政当局无法收缴收入,这限制了它们的投资,只能从事社会和经济影响极低的工作。从功能角度看,权力下放导致了抱负迥异的行动者的倍增,但也造成了角色的混淆和无知。根据这些结果,我们建议地方政府开放地理信息系统,该系统具备有效更好地管理空间数据和领土的方法、技术和工具。In the process of creating this system,加成used for the collection、存储、分析、建模,display and management of航天信息、重要is an opportunity代表迈向协商the implementation of a framework that the representativeness integrates at different)中的水平,一切利益相关者地方治理的客观、skills and on the field。
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引用次数: 0
Chemical weathering intensity and rare earth elements release from a chlorite schist profile in a humid tropical area, Bengbis, Southern Cameroon 喀麦隆南部本比斯潮湿热带地区绿泥石片岩剖面的化学风化强度和稀土元素释放
Pub Date : 2021-01-27 DOI: 10.4314/JCAS.V16I2.5
V. L. Onana, Estelle Ndome Effoudou, Sylvie Désirée Noa Tang, V. Kabeyene, G. Ekodeck
ResumeUn profil d’alteration developpe sur chloritoschistes de la zone de Bengbis (Sud Cameroun) a ete choisi pour quantifier l’intensite de l’alteration et comprendre le comportement des terres rares. Les valeurs de l’indice d’alteration mafique combinees aux diagrammes ternaires du systeme Al – Fe – Mg – Ca – Na – K montrent que l’hydrolyse des feldspaths est proportionnelle a celle des mineraux mafiques (pertes en Mg), bien que l’hydrolyse des plagioclases (Ca, Na) soit plus intense que celle des mineraux ferromagnesiens. Les materiaux d’alteration etudies sont localises dans le domaine de la kaolinitisation, a l’exception des materiaux nodulaires qui sont legerement latritiss. La modification du comportement du Mg dans le milieu d’alteration s’exprime par les faibles valeurs du rapport Ca/Mg. Le potassium et Be sont lessives dans le sol en association avec Mg. L’ordre de mobilite des elements dans l’environnement d’alteration etudie est : Ca ≈ Na > Fe2+ ≈ Sr > Mg ≈ Co > Mn > Li > Ba > Rb > P > Cd > Ni > Si > Be > K > Sn. Les enrichissements en K, Cs et Be dans les saprolites sont lies a la presence d’illite. L’accumulation en Cs dans le sol est due a la presence de kaolinite. Le systeme le plus stable dans le milieu d’alteration etudie est : Hf – Nb – W – U. Les saprolites, les materiaux nodulaires et les materiaux argileux meubles superficiels sont appauvris en terres rares par rapport a la roche mere. Les terres rares presentent trois types de comportement le long du profil d’alteration, comme l’indiquent les valeurs du rapport (La/Yb)N ((La/Yb)N 1). Les terres rares legeres et les terres rares moyennes s’accumulent dans les materiaux d’alteration pour des valeurs de pH comprises entre 5,5 et 5,6 et pour celles de Eh variant entre +60 et +70mV. L’ordre de mobilite de ces elements dans ces materiaux est le suivant : terres rares moyennes > terres rares lourdes terres rares legeres. Ce fait est contre-intuitif, car les terres lourdes sont plus mobiles dans les environnemenst supergenes que les terres rares legeres. L’adsorption ou la co-precipitation de ces terres rares sur les oxydes de fer peut principalement controler la concentration de ces elements dans le profil d’alteration. Les faibles anomalies en Ce dans les materiaux d’alteration de la zone de Bengbis, dues au changement de Ce3+ en Ce4+, sont probablement dues a la presence de faibles quantites de rhabdophane. Les materiaux d’alteration etudies presentent un fractionnement en Gd (Gd/Gd* ~0.70 – 0.84) dues a une intense lixiviation. Ce fait a rarement ete signale dans un environnement d’alteration lateritique. Il semble qu’une partie de la distribution et de la remobilisation du gadolinium soit controlee par des mineraux mafiques dans les materiaux d’alteration etudies. La distribution et la mobilisation des terres rares sont donc controlees par (1) l’adsorption ou la coprecipitation dans les mineraux mafiques et Fe, (2) et legerement par les mineraux contenant des terres rares tels
本比斯地区风化物质中Ce3+向Ce4+转变导致的弱Ce异常,可能是由于横纹石含量较低所致。受化学浸出的影响,风化材料中Gd呈分异分布(Gd/Gd* ~0.70 ~ 0.84)。这一现象在红土风化环境中鲜有报道。研究表明,风化物质中的镁基性矿物控制了部分Gd的分布和再活化。因此,稀土的分布和运移受(1)基性矿物和铁矿物的吸附或共沉淀控制,(2)风化剖面中发现的含稀土矿物(如横纹石)的影响较小。
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引用次数: 2
Evaluation de la gestion des déchets solides hospitaliers: cas de l’hôpital Jamôt de Yaoundé et de l’hôpital de district de Biyem-Assi 医院固体废物管理评估:雅温得jamot医院和Biyem-Assi地区医院的案例
Pub Date : 2021-01-27 DOI: 10.4314/JCAS.V16I2.1
Severin Mbog Mbog, Jacob Bidias, Olivier T Sosso Mayi, Dieudonné Bitondo, Innocent Ndoh Mbue
ResumeL’objectif general de cet etude est d’ameliorer la gestion des dechets solides au sein de l’Hopital de district de Biyem-Assi et a l’hopital Jamot de Yaounde. La demarche methodologique menee de juillet 2012 a septembre 2013e adoptee, a consiste a des entretiens et des observations directes et l’administration des questionnaires semi-structures. Cette methodologie a permis de realiser l’etude en trois phases la recherche documentaire, la collecte et le traitement des donnees:Les resultats obtenus font ressortir deux grandes categories de dechets : les dechets assimilables aux ordures menageres (DAOM); les dechets d’activites de soins a risques (DASRI), 24,46 % est assimilable aux (DAOM) et 75,54 % (DASRI) a l’Hopital Jamot de Yaounde. Tandis qu’a l’Hopital de District de Biyem-Assi 86,23 % est assimilable aux (DAOM) et 13,77 % (DASRI). Par contre l’appreciation de l’efficacite du systeme de gestion des dechets solides revele qu’a l’HJY apres des interviews demontre que le systeme est mauvais: tandis qu’a l’HDB, le systeme est plus pris en charge par le personnel. Au vu des observations et constats faites, une amelioration du systeme de gestion des dechets solides et l’accroissement de la sensibilisation du personnel et des usagers sur les modes de gestion des dechets solides s’imposent. AbstractThe general objective of this study is to improve the management of the solid waste within Biyem-AssiDistrict Hospital and the Jamot Hospital , Yaounde.The work was carried out from July 2012 to September 2013,and consisted to interviews and the direct observations and the administration of semi-structured questionnaires. This methodology permitted us to achieve the survey in three phases: the documentary research, the collection and the treatment of the data:The results obtained revealed two big categories of garbage taken out again: the garbage assimilated to the household waste (HhW); hospital waste (HoW). About 24, 46 % was assimilated to (HhW) and 75, 54 % (HoW) in the Yaounde Jamot Hospital. While to the hospital of District of Biyem-Assi 86, 23 % is assimilated to them (HhW) and 13, 77% (DHoW). On the other hand the appreciation of the efficiency of the system of management of the solid waste reveals that to the HJY after interviews demonstrates that the system is bad: while to the HDB, the system is taken more in charge by the staff. Within sight of the observations and reports made, an improvement of the system of management of the strong garbage and the growth of the sensitization of the staff and users on the fashions of management of the strong garbage impose themselves.
这项研究的总体目标是改善Biyem-Assi地区医院和雅温得Jamot医院的固体废物管理。2012年7月至2013年9月采用的方法包括访谈、直接观察和半结构化问卷的管理。该方法允许研究分三个阶段进行:文献检索、数据收集和处理:获得的结果突出了两大类废物:家庭废物(DAOM);高风险护理活动(DASRI)的废物占24.46%,雅温得Jamot医院的废物占75.54%。而在Biyem-Assi地区医院,86.23%与DAOM和13.77% (DASRI)相似。另一方面,hjy在访谈后对固体废物管理系统有效性的评估表明,该系统是糟糕的:而在组屋,该系统更多地由员工管理。根据这些观察和调查结果,有必要改进固体废物管理系统,并提高工作人员和用户对固体废物管理方法的认识。摘要本研究的总体目标是改善雅温得Biyem-AssiDistrict医院和Jamot医院的固体废物管理。这项工作于2012年7月至2013年9月进行,包括访谈、直接观察和半结构化问卷的管理。这种方法使我们能够分三个阶段进行调查:记录片研究、数据的收集和处理;所获得的结果揭示了再次处理的两大类垃圾:垃圾与家庭垃圾同化;医院废物(如何)。在雅温得贾莫特医院,24.46%的人被同化(HhW), 75.54%的人被同化(HoW)。在Biyem-Assi地区医院,86,23 %的人被同化(HhW), 13.77%的人被同化(独桅帆船)。另一方面,对固体废物管理系统效率的评价表明,对HJY的访谈表明该系统是不好的:而对组屋组来说,该系统更多地由工作人员负责。根据所作的观察和报告,强垃圾管理制度的改进以及工作人员和用户对强垃圾管理方式的日益敏感,本身就需要改进。
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Journal of the Cameroon academy of sciences
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