Kenmogne Simo Thierry Césaire, D. Albert, Mana Ngangue Sastile, Ntsomboh-Ntsefong Godswill, Ngando Ebongue George, Mpondo Mpondo Emmanuel
Les huiles vegetales raffinees sont des sources d’energie, d’acides gras essentiels, d’antioxydants et de vitamines liposolubles. Elles permettent de lutter contre la malnutrition et le vieillissement cellulaire. Les mauvaises conditions d’extraction, de raffinage, de conservation et de stockage peuvent alterer l’identite et la qualite de ces produits. L’objectif de ce travail etait d’evaluer l’origine et l’identite de 56 echantillons d’huiles vegetales commercialisees a Douala. Pour ce faire nous avons etudie la representativite des varietes d’huiles sur le marche et leur origine, l’indice d’iode, l’indice de saponification et la conformite de l’etiquetage. Les resultats montrent que le marche des huiles vegetales raffinees est domine par les produits importes avec 57,2% de part de marche. Moins de 30% des echantillons analyses etaient conformes a la norme camerounaise NC 04 :2000-20sur l’etiquetage des denrees alimentaires pre emballees. Aucun echantillon analyse n’a eu un indice d’iode, ni de saponification, conforme a la norme du Codex Alimentarius et la norme camerounaise NC 77 : 2002-03, REV.1. de 2011 portant sur les huiles vegetales enrichies en vitamine A. Les huiles raffinees analysees auraient ete adulterees ou auraient subies une alteration avancee par le phenomene d’auto oxydation catalyse par la chaleur. Elles ne seraient pas des corps gras purs. Cette etude suggere que des efforts considerables doivent etre entrepris en plus des acquis dont dispose le Cameroun dans le domaine du controle de qualite des denrees alimentaires. Mots cles: Huiles vegetales, Controle Qualite, Norme, Conformite d’etiquetage English Abstract Refined vegetable oils are sources of energy, essential fatty acids, antioxidants and fat-soluble vitamins. They help fight against malnutrition and cellular aging. Poor extraction, refining, storage and storageconditions can alter the identity and quality of these products. The objective of this work was to evaluate the origin and identity of 56 vegetable oil samples marketed in Douala. We studied the representativeness of the different oil varieties from the market and their origin, the iodine index, the saponification index and the conformity of the labeling. The results show that the market for refined vegetable oils is dominated by imported products with a 57.2% market share. Less than 30% of the samples analyzed complied with the Cameroonian standard NC 04: 2000-20 on the labeling of prepackaged foods. No samples analyzed had an iodine or saponification index in accordance with the Codex Alimentarius standard and the Cameroonian standard NC 77: 2002-03, REV.1. Of 2011 on vegetable oils fortified with vitamin A. The refined oils analyzed were adulterated or might have undergone advanced alteration by the phenomenon of auto-oxidation catalyzed by heat. These oils are therefore not really pure fats. This study suggests that considerable efforts must be made in addition to Cameroon’s achievements in the field of qual
{"title":"Etude de l’Origine et de L’Identité de quelques Types d’Huiles Végétales Raffinées Commercialisées à Douala/Cameroun","authors":"Kenmogne Simo Thierry Césaire, D. Albert, Mana Ngangue Sastile, Ntsomboh-Ntsefong Godswill, Ngando Ebongue George, Mpondo Mpondo Emmanuel","doi":"10.4314/JCAS.V15I1.3","DOIUrl":"https://doi.org/10.4314/JCAS.V15I1.3","url":null,"abstract":"Les huiles vegetales raffinees sont des sources d’energie, d’acides gras essentiels, d’antioxydants et de vitamines liposolubles. Elles permettent de lutter contre la malnutrition et le vieillissement cellulaire. Les mauvaises conditions d’extraction, de raffinage, de conservation et de stockage peuvent alterer l’identite et la qualite de ces produits. L’objectif de ce travail etait d’evaluer l’origine et l’identite de 56 echantillons d’huiles vegetales commercialisees a Douala. Pour ce faire nous avons etudie la representativite des varietes d’huiles sur le marche et leur origine, l’indice d’iode, l’indice de saponification et la conformite de l’etiquetage. Les resultats montrent que le marche des huiles vegetales raffinees est domine par les produits importes avec 57,2% de part de marche. Moins de 30% des echantillons analyses etaient conformes a la norme camerounaise NC 04 :2000-20sur l’etiquetage des denrees alimentaires pre emballees. Aucun echantillon analyse n’a eu un indice d’iode, ni de saponification, conforme a la norme du Codex Alimentarius et la norme camerounaise NC 77 : 2002-03, REV.1. de 2011 portant sur les huiles vegetales enrichies en vitamine A. Les huiles raffinees analysees auraient ete adulterees ou auraient subies une alteration avancee par le phenomene d’auto oxydation catalyse par la chaleur. Elles ne seraient pas des corps gras purs. Cette etude suggere que des efforts considerables doivent etre entrepris en plus des acquis dont dispose le Cameroun dans le domaine du controle de qualite des denrees alimentaires. Mots cles: Huiles vegetales, Controle Qualite, Norme, Conformite d’etiquetage English Abstract Refined vegetable oils are sources of energy, essential fatty acids, antioxidants and fat-soluble vitamins. They help fight against malnutrition and cellular aging. Poor extraction, refining, storage and storageconditions can alter the identity and quality of these products. The objective of this work was to evaluate the origin and identity of 56 vegetable oil samples marketed in Douala. We studied the representativeness of the different oil varieties from the market and their origin, the iodine index, the saponification index and the conformity of the labeling. The results show that the market for refined vegetable oils is dominated by imported products with a 57.2% market share. Less than 30% of the samples analyzed complied with the Cameroonian standard NC 04: 2000-20 on the labeling of prepackaged foods. No samples analyzed had an iodine or saponification index in accordance with the Codex Alimentarius standard and the Cameroonian standard NC 77: 2002-03, REV.1. Of 2011 on vegetable oils fortified with vitamin A. The refined oils analyzed were adulterated or might have undergone advanced alteration by the phenomenon of auto-oxidation catalyzed by heat. These oils are therefore not really pure fats. This study suggests that considerable efforts must be made in addition to Cameroon’s achievements in the field of qual","PeriodicalId":383706,"journal":{"name":"Journal of the Cameroon academy of sciences","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122869554","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This review focuses on the role that African Traditional Medicine can play in addressing the health problems of refugees in the central sub-region with focus on Cameroon. This paper is based on a review of literature on the influx of refugees and their well-being. Over 400 000 refugees live in Cameroon particularly in the Far North (Nigerians) and in the Eastern (Central Africans Refugees) Regions of Cameroon. About 80 per cent of the refugees arriving in Cameroon suffer from serious ailments such as malaria, diarrhea, anemia and respiratory tract infections, while more than 20 per cent of children are severely malnourished. To curb these diseases UNHCR and NGOs provide medications to refugees which often arrive late; some of which at times expire in stock or some different distribution centres run out of stock. An aid could come from Traditional Medicine Practitioners who have been very effective in management of disease conditions in refugee camps in some countries in the world. The Cameroon Traditional Medicine if well-developed will do same to act as first-aid before the arrival of conventional medicine or complement western medicine to manage patients who do not accept western medicine because of cultural believes. Cette revue met l’accent sur le role que peut jouer la Medecine Traditionnelle africaine sur l’amelioration de la sante des refugiees dans la sous-region, en se focalisant sur le Cameroun. Cet article est base sur une revue de la litterature de l’afflux des refugies et leur bien-etre. Plus de 400 000 refugiees vivent au Cameroun, en particulier dans l’Extreme-Nord (Nigerians) et dans les regions de l’Est (Refugies centrafricains). Environ 80 % des refugies qui arrivent au Cameroun souffrent de maladies graves telles que le paludisme, la diarrhee, l’anemie et les infections des voies respiratoires, tandis que 20 % des enfants souffrent de malnutrition grave. Pour lutter contre ces maladies, le HCR et les ONG fournissent aux refugies des medicaments qui malheureusement arrivent parfois en retard, certains d’entre eux expirent en stock et certains centres de distribution sont a court de stocks. Les praticiens de la Medecine Traditionnelle qui ont l’experience de la gestion des maladies dans les camps des refugies de par le monde pourraient apporter une aide precieuse. La Medecine Traditionnelle camerounaise, si elle est bien developpee fera pareil pour les soins de premiers secours avant l’arrivee de la Medecine Conventionnelle ou completera la medecine occidentale pour traiter les patients refusent cette derniere pour des raisons culturelles.
本次审查的重点是非洲传统医学在解决中部分区域难民健康问题方面可以发挥的作用，重点是喀麦隆。本文基于对难民涌入及其福祉的文献综述。超过40万难民居住在喀麦隆，特别是在喀麦隆的远北部(尼日利亚人)和东部(中非难民)地区。抵达喀麦隆的难民中约有80%患有疟疾、腹泻、贫血和呼吸道感染等严重疾病，而20%以上的儿童严重营养不良。为了控制这些疾病，难民专员办事处和非政府组织向往往姗姗来迟的难民提供药品;其中一些有时库存过期，或者一些不同的配送中心缺货。援助可以来自传统医学从业者，他们在世界上一些国家的难民营中非常有效地管理了疾病状况。喀麦隆传统医学如果发展良好，也可以在传统医学到来之前起到急救作用，或者作为西方医学的补充，来管理由于文化信仰而不接受西方医学的病人。我们将在“非洲传统医学”和“非洲难民健康状况改善”以及“喀麦隆难民健康状况改善”方面取得进展。这篇文章是关于难民流入的文学研究的基础。另外还有40万来自喀麦隆的难民，特别是极端北部的难民(尼日利亚人)和东部的难民(中非难民)。抵达喀麦隆的难民中有80%患有疾病、痢疾、腹泻、呼吸道感染，20%患有营养不良。为了预防疾病，难民专员办事处和联合国难民事务高级专员办事处向难民发放了药品和治疗药物，有些中心提供了药品和治疗药物，有些分发中心提供了药品和治疗药物。传统医学的实践者没有经验，他们没有经验，他们没有经验，他们没有经验，他们没有经验，他们没有经验，他们没有经验，他们没有经验，他们没有经验，他们没有经验，他们没有经验，他们没有经验。《传统医学》(the medical traditional - nelle cameronounaise)，《传统医学》(the medical convention)，《传统医学》(the medical convention)，《传统医学》(the medical convention)，《传统医学》(the medical)，《传统医学》(the medical)，《传统医学》(the medical)，《传统医学》(the medical)
{"title":"Refugee health problems in the central African subregion: The role of traditional medicine","authors":"J. G. Nzweundji, G. Agbor","doi":"10.4314/jcas.v14i3.3","DOIUrl":"https://doi.org/10.4314/jcas.v14i3.3","url":null,"abstract":"This review focuses on the role that African Traditional Medicine can play in addressing the health problems of refugees in the central sub-region with focus on Cameroon. This paper is based on a review of literature on the influx of refugees and their well-being. Over 400 000 refugees live in Cameroon particularly in the Far North (Nigerians) and in the Eastern (Central Africans Refugees) Regions of Cameroon. About 80 per cent of the refugees arriving in Cameroon suffer from serious ailments such as malaria, diarrhea, anemia and respiratory tract infections, while more than 20 per cent of children are severely malnourished. To curb these diseases UNHCR and NGOs provide medications to refugees which often arrive late; some of which at times expire in stock or some different distribution centres run out of stock. An aid could come from Traditional Medicine Practitioners who have been very effective in management of disease conditions in refugee camps in some countries in the world. The Cameroon Traditional Medicine if well-developed will do same to act as first-aid before the arrival of conventional medicine or complement western medicine to manage patients who do not accept western medicine because of cultural believes. Cette revue met l’accent sur le role que peut jouer la Medecine Traditionnelle africaine sur l’amelioration de la sante des refugiees dans la sous-region, en se focalisant sur le Cameroun. Cet article est base sur une revue de la litterature de l’afflux des refugies et leur bien-etre. Plus de 400 000 refugiees vivent au Cameroun, en particulier dans l’Extreme-Nord (Nigerians) et dans les regions de l’Est (Refugies centrafricains). Environ 80 % des refugies qui arrivent au Cameroun souffrent de maladies graves telles que le paludisme, la diarrhee, l’anemie et les infections des voies respiratoires, tandis que 20 % des enfants souffrent de malnutrition grave. Pour lutter contre ces maladies, le HCR et les ONG fournissent aux refugies des medicaments qui malheureusement arrivent parfois en retard, certains d’entre eux expirent en stock et certains centres de distribution sont a court de stocks. Les praticiens de la Medecine Traditionnelle qui ont l’experience de la gestion des maladies dans les camps des refugies de par le monde pourraient apporter une aide precieuse. La Medecine Traditionnelle camerounaise, si elle est bien developpee fera pareil pour les soins de premiers secours avant l’arrivee de la Medecine Conventionnelle ou completera la medecine occidentale pour traiter les patients refusent cette derniere pour des raisons culturelles.","PeriodicalId":383706,"journal":{"name":"Journal of the Cameroon academy of sciences","volume":"72 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130137649","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
K. Nyongbela, M. Samje, A. F. Awantu, T. E. Tiku, F. Cho-Ngwa
As part of our efforts towards identifying and subsequently developing lead compounds from medicinal plants of Cameroon to combat neglected tropical diseases, we embarked to phytochemically investigate Enantia chlorantha (Syn. Annickia chlorantha). The rationale for choosing this plant is its numerous uses in folk medicine in Cameroon and other parts of Africa. In Cameroon the quaternary protoberberine alkaloids, columbamine (2), palmatine (3) and jatrorrizine (4) have been isolated from the stem back and combined to produce a phytomedicine (HEPAZOR®) used in the treatment of viral hepatitis. An alkaloidal extraction of the methanolic extract of the stem bark of the plant was carried-out and this afforded yellow amorphous solids whose structure was obtained using routine nuclear magnetic resonance spectroscopy (NMR), high pressure liquid chromatography coupled to an electrospray mass spectrometer (HPLC-ESI-MS) and comparison with literature. The compound was identified as pseudopalmatine (1), a quaternary protoberberine alkaloid. Preliminary screening of the compound on both adult and juvenile worms of Onchocerca ochengi, a close relative of Onchocerca volvulus, the parasite responsible for human onchocerciasis (river blindness), showed that compound (1) was inactive at a concentration of 500 μg/mL on the adult worms, but inhibited microfilariae motility completely at this same concentration and by 50 % at 250 μg/mL and was thus considered active. While this work to the best of our knowledge constitutes the first report on the anti-onchocercal activity of quaternary protoberberine alkaloids in general and pseudopalmatine (1) in particular isolated from E. Chlorantha, it has however opened a window for further investigation of the anti-onchoceral activity of this class of compounds. Key words: anti-onchocercal, pseudopalmatine, alkaloid, Enantia chlorantha
{"title":"Evaluation of anti-onchocercal activity of pseudopalmatine, a quaternary protoberberine alkaloid of Enantia chlorantha (Syn. Annickia chlorantha)","authors":"K. Nyongbela, M. Samje, A. F. Awantu, T. E. Tiku, F. Cho-Ngwa","doi":"10.4314/JCAS.V14I3.1","DOIUrl":"https://doi.org/10.4314/JCAS.V14I3.1","url":null,"abstract":"As part of our efforts towards identifying and subsequently developing lead compounds from medicinal plants of Cameroon to combat neglected tropical diseases, we embarked to phytochemically investigate Enantia chlorantha (Syn. Annickia chlorantha). The rationale for choosing this plant is its numerous uses in folk medicine in Cameroon and other parts of Africa. In Cameroon the quaternary protoberberine alkaloids, columbamine (2), palmatine (3) and jatrorrizine (4) have been isolated from the stem back and combined to produce a phytomedicine (HEPAZOR®) used in the treatment of viral hepatitis. An alkaloidal extraction of the methanolic extract of the stem bark of the plant was carried-out and this afforded yellow amorphous solids whose structure was obtained using routine nuclear magnetic resonance spectroscopy (NMR), high pressure liquid chromatography coupled to an electrospray mass spectrometer (HPLC-ESI-MS) and comparison with literature. The compound was identified as pseudopalmatine (1), a quaternary protoberberine alkaloid. Preliminary screening of the compound on both adult and juvenile worms of Onchocerca ochengi, a close relative of Onchocerca volvulus, the parasite responsible for human onchocerciasis (river blindness), showed that compound (1) was inactive at a concentration of 500 μg/mL on the adult worms, but inhibited microfilariae motility completely at this same concentration and by 50 % at 250 μg/mL and was thus considered active. While this work to the best of our knowledge constitutes the first report on the anti-onchocercal activity of quaternary protoberberine alkaloids in general and pseudopalmatine (1) in particular isolated from E. Chlorantha, it has however opened a window for further investigation of the anti-onchoceral activity of this class of compounds. Key words: anti-onchocercal, pseudopalmatine, alkaloid, Enantia chlorantha","PeriodicalId":383706,"journal":{"name":"Journal of the Cameroon academy of sciences","volume":"18 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131892788","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mboudou Guillaume Ewodo, André Bon, Ambomo Etienne Bineli, N’dalna Nangyana, Katcheba Patalet Gaiba, A. Ombolo
L’hydrogeochimie des aquiferes de subsurface et profond dans la ville de N’Djamena a ete etudiee a partir des techniques conventionnelles d’analyse et des graphiques ploter. Le comportement ionique, les facies hydrochimiques et les facteurs controlant la chimie des eaux souterraines ont ete examinees et definies. Les resultats indiquent que l’abondance relative des principales especes dissoutes est Ca2 + > Na+ > Mg2 + > K + pour les cations dans les deux types d’aquifere et HCOa 3 - > SO 4 2- > Cl - >NO 3 - et HCO 3 - > Cl - > SO 4 2- > NO 3 - pour les anions respectivement dans l’aquifere de subsurface et profond. Les deux principaux facies chimiques d’eau rencontres sont : le facies calco-magnesien bicarbonate (CaMg-HCO 3 -) et le facies sodique potassique bicarbonate (NaK-HCO 3 -). Dans ces aquiferes, les mineraux sulfates sont sous satures. Concernant les mineraux siliceux, la Calcedoine et le quartz sont sursatures, par contre la silice amorphe est sous saturee. Mots cle : Hydrogeochimie, aquifere de subsurface, aquifere de profond, N’Djamena, Tchad
利用常规分析技术和绘图仪对恩贾梅纳市地下和深层含水层的水文地球化学进行了研究。对离子行为、水化学相和控制地下水化学的因素进行了研究和定义。结果显示主要的相对丰度越冬场溶解是Ca2 + > lg > om2 + K +对于两类中的阳离子和d’aquifere HCOa 3 - 4 > SO - Cl - > 3号- 2和3 HCO - Cl - > SO 2 > 3号- 4中的阴离子,分别为l’aquifere表层和深层的。遇到的两个主要化学水相是碳酸氢钙镁相(CaMg-HCO 3 -)和碳酸氢钠钾相(NaK-HCO 3 -)。在这些含水层中，硫酸盐矿物是饱和的。在硅质矿物中，玉髓和石英是过饱和的，而无定形硅是过饱和的。关键词:水文地球化学，地下含水层，深层含水层，乍得恩贾梅纳
{"title":"Hydrogéochimique des aquifères de subsurface et profond de la ville de n’djamena","authors":"Mboudou Guillaume Ewodo, André Bon, Ambomo Etienne Bineli, N’dalna Nangyana, Katcheba Patalet Gaiba, A. Ombolo","doi":"10.4314/JCAS.V14I3.6","DOIUrl":"https://doi.org/10.4314/JCAS.V14I3.6","url":null,"abstract":"L’hydrogeochimie des aquiferes de subsurface et profond dans la ville de N’Djamena a ete etudiee a partir des techniques conventionnelles d’analyse et des graphiques ploter. Le comportement ionique, les facies hydrochimiques et les facteurs controlant la chimie des eaux souterraines ont ete examinees et definies. Les resultats indiquent que l’abondance relative des principales especes dissoutes est Ca2 + > Na+ > Mg2 + > K + pour les cations dans les deux types d’aquifere et HCOa 3 - > SO 4 2- > Cl - >NO 3 - et HCO 3 - > Cl - > SO 4 2- > NO 3 - pour les anions respectivement dans l’aquifere de subsurface et profond. Les deux principaux facies chimiques d’eau rencontres sont : le facies calco-magnesien bicarbonate (CaMg-HCO 3 -) et le facies sodique potassique bicarbonate (NaK-HCO 3 -). Dans ces aquiferes, les mineraux sulfates sont sous satures. Concernant les mineraux siliceux, la Calcedoine et le quartz sont sursatures, par contre la silice amorphe est sous saturee. Mots cle : Hydrogeochimie, aquifere de subsurface, aquifere de profond, N’Djamena, Tchad","PeriodicalId":383706,"journal":{"name":"Journal of the Cameroon academy of sciences","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127457216","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mbida Yem, J. Atangana, S. P. K. N. Lebogo, M. M. Essi
The Paleocene aquifer of the Douala-Massoumbou sub basin is a rhythmic sequence of sand and shale deposits. Resistivity pseudosections and profiles of half-distance between current electrodes of 350m were acquired at 20 different sites of the Douala-Massoumbou subbasin. These data coupled with mud and gamma-ray logging of deep groundwater boreholes led to the identification of two major sand sequences through the Paleaocene-Eocene stratigraphic section. The upper sequence associated with Ypresian 30-50 m thick unconformity made up with semi-conductive records, is punctuated by lenses of substantially water bearing sand (WBS). While the lower sequence locally associated with H2S and iron pollution plumes, displays high conductive records. In such sequences, the distribution of sand and clay deposits settled by channel incision appears fundamental in predicting reservoir geometry and the hydrological potential of the Paleocene WBS. Keywords : Sag basin, electrical tomography, Paleocene formation, water-bearing sand. L’aquifere du Paleocene du sous-bassin de Douala-Massoumbou est une sequence rythmique de depots de sable et d’argile. Des sondages geoelectriques tripole (OA=350m) et des tomographies de resistivite ont ete acquis sur 20 sites differents de la zone de faible enfouissement de cet aquifere. Ces donnees, couplees aux resultats des diagraphies gamma-ray et des deblais des forages hydrogeologiques profonds, ont permis d’identifier deux sequences de sable hydrostratigraphique au sein de l’aquifere paleoceneeocene. La sequence superieure semi-conductrice correspond a depots de sable aquifere sain, epaisse de 30 a 50 m et associes a la discordance ypresienne. La sequence inferieure tres conductrice, correspond a des chenaux de sable aquifere pollue par le sulfure d’hydrogene (H2S) et le fer. La mise en correlation de l’ensemble des resultats obtenus a permis de constater que la prise en compte du developpement spatial des chemins hydrologiques fossiles est un critere fondamental pour la predire la distribution et l’exploitation des niveaux de sable aquifere sain du Paleocene du sous-bassin de Douala-Massoumbou. Mots cles : Bassin de fosse d’effondrement, tomographie electrique, Formation paleocene, Sag basin, electrical tomography, Paleocene formation, niveaux de sable aquifere sain.
{"title":"Electrical resistivity tomography of the Douala-Massoumbou Paleocene- Eocene aquifer (Cameroon Atlantic Margin)","authors":"Mbida Yem, J. Atangana, S. P. K. N. Lebogo, M. M. Essi","doi":"10.4314/JCAS.V14I3.5","DOIUrl":"https://doi.org/10.4314/JCAS.V14I3.5","url":null,"abstract":"The Paleocene aquifer of the Douala-Massoumbou sub basin is a rhythmic sequence of sand and shale deposits. Resistivity pseudosections and profiles of half-distance between current electrodes of 350m were acquired at 20 different sites of the Douala-Massoumbou subbasin. These data coupled with mud and gamma-ray logging of deep groundwater boreholes led to the identification of two major sand sequences through the Paleaocene-Eocene stratigraphic section. The upper sequence associated with Ypresian 30-50 m thick unconformity made up with semi-conductive records, is punctuated by lenses of substantially water bearing sand (WBS). While the lower sequence locally associated with H2S and iron pollution plumes, displays high conductive records. In such sequences, the distribution of sand and clay deposits settled by channel incision appears fundamental in predicting reservoir geometry and the hydrological potential of the Paleocene WBS. Keywords : Sag basin, electrical tomography, Paleocene formation, water-bearing sand. L’aquifere du Paleocene du sous-bassin de Douala-Massoumbou est une sequence rythmique de depots de sable et d’argile. Des sondages geoelectriques tripole (OA=350m) et des tomographies de resistivite ont ete acquis sur 20 sites differents de la zone de faible enfouissement de cet aquifere. Ces donnees, couplees aux resultats des diagraphies gamma-ray et des deblais des forages hydrogeologiques profonds, ont permis d’identifier deux sequences de sable hydrostratigraphique au sein de l’aquifere paleoceneeocene. La sequence superieure semi-conductrice correspond a depots de sable aquifere sain, epaisse de 30 a 50 m et associes a la discordance ypresienne. La sequence inferieure tres conductrice, correspond a des chenaux de sable aquifere pollue par le sulfure d’hydrogene (H2S) et le fer. La mise en correlation de l’ensemble des resultats obtenus a permis de constater que la prise en compte du developpement spatial des chemins hydrologiques fossiles est un critere fondamental pour la predire la distribution et l’exploitation des niveaux de sable aquifere sain du Paleocene du sous-bassin de Douala-Massoumbou. Mots cles : Bassin de fosse d’effondrement, tomographie electrique, Formation paleocene, Sag basin, electrical tomography, Paleocene formation, niveaux de sable aquifere sain.","PeriodicalId":383706,"journal":{"name":"Journal of the Cameroon academy of sciences","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130316303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Climate change along with global population increase pose a challenge to worldwide crop production and soil health. There is a need to intensify agricultural production in a sustainable manner and to find solutions to combat abiotic and biotic stress situations. Plant roots can be colonized by a variety of favorable species and genera that promote plant growth. A systems approach to integrating plant breeding and microbiome via applying novel molecular tools, screening technologies and precision phenotyping has the potential to advance the microbial reproducible application under natural conditions. Le changement climatique ainsi que l’augmentation de la population mondiale posent un defi pour la production agricole mondiale et la sante des sols. Il est necessaire d’intensifier durablement la production agricole et de trouver des solutions pour lutter contre les situations de stress abiotiques et biotiques. Les racines des plantes peuvent etre colonisees par une variete d’especes et de genres favorables qui favorisent la croissance des plantes. Une approche systemique d’integration de la selection vegetale et du microbiome via l’application de nouveaux outils moleculaires, de technologies de criblage et d’un phenotypage de precision pourrait faire progresser l’application reproductible microbienne dans des conditions naturelles
{"title":"The plant microbiome as a resource to increase crop productivity and soil resilience: A systems approach","authors":"S. Timmusk, C. Zucca","doi":"10.4314/JCAS.V14I3.2","DOIUrl":"https://doi.org/10.4314/JCAS.V14I3.2","url":null,"abstract":"Climate change along with global population increase pose a challenge to worldwide crop production and soil health. There is a need to intensify agricultural production in a sustainable manner and to find solutions to combat abiotic and biotic stress situations. Plant roots can be colonized by a variety of favorable species and genera that promote plant growth. A systems approach to integrating plant breeding and microbiome via applying novel molecular tools, screening technologies and precision phenotyping has the potential to advance the microbial reproducible application under natural conditions. Le changement climatique ainsi que l’augmentation de la population mondiale posent un defi pour la production agricole mondiale et la sante des sols. Il est necessaire d’intensifier durablement la production agricole et de trouver des solutions pour lutter contre les situations de stress abiotiques et biotiques. Les racines des plantes peuvent etre colonisees par une variete d’especes et de genres favorables qui favorisent la croissance des plantes. Une approche systemique d’integration de la selection vegetale et du microbiome via l’application de nouveaux outils moleculaires, de technologies de criblage et d’un phenotypage de precision pourrait faire progresser l’application reproductible microbienne dans des conditions naturelles","PeriodicalId":383706,"journal":{"name":"Journal of the Cameroon academy of sciences","volume":"130 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133000527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Depth uncertainty is one of the major uncertainties associated with hydrocarbon field development. This uncertainty mostly arises due to the complexity of the subsurface, paucity of data, time-to-depth conversion, seismic picks, fault positioning and well ties. These uncertainties explain the non-uniqueness of models built and can have a significant impact on fluid contact and hydrocarbon in-place evaluation. To manage depth uncertainty, The Polynomial and Vo_K method were adopted to build velocity models for depth conversion and residual analysis for several reservoir levels to determine the method that will give the best depth residuals. Depth conversion residual analysis result of both velocity models for the reservoirs studied gave average depth residual of less than 50ft for reservoir levels below 9000ft. As the depth increases, the polynomial method derived average residual becomes unreliable with depth uncertainty of over 100ft for the deeper MOT reservoir, compared to 11. 65ft of the Vo_K method for the same reservoir. This was expected at depth since the polymonial method adopts average velocities while the Vo_K method uses instantaneous velocity. Hence, the latter is expected to give a better result at great depth during depth conversion and should be preferably employed for velocity modeling and depth conversion study of reservoir in the Niger delta Basin. Key Words : Depth-Conversion, Velocity-Modelling, Polynomial-Function, Vo_K -Function, Niger- Delta.
{"title":"Velocity modelling and depth conversion uncertainty analysis of onshore reservoirs in the Niger Delta basin","authors":"A. Ogbamikhumi, O. Aderibigbe","doi":"10.4314/JCAS.V14I3.7","DOIUrl":"https://doi.org/10.4314/JCAS.V14I3.7","url":null,"abstract":"Depth uncertainty is one of the major uncertainties associated with hydrocarbon field development. This uncertainty mostly arises due to the complexity of the subsurface, paucity of data, time-to-depth conversion, seismic picks, fault positioning and well ties. These uncertainties explain the non-uniqueness of models built and can have a significant impact on fluid contact and hydrocarbon in-place evaluation. To manage depth uncertainty, The Polynomial and Vo_K method were adopted to build velocity models for depth conversion and residual analysis for several reservoir levels to determine the method that will give the best depth residuals. Depth conversion residual analysis result of both velocity models for the reservoirs studied gave average depth residual of less than 50ft for reservoir levels below 9000ft. As the depth increases, the polynomial method derived average residual becomes unreliable with depth uncertainty of over 100ft for the deeper MOT reservoir, compared to 11. 65ft of the Vo_K method for the same reservoir. This was expected at depth since the polymonial method adopts average velocities while the Vo_K method uses instantaneous velocity. Hence, the latter is expected to give a better result at great depth during depth conversion and should be preferably employed for velocity modeling and depth conversion study of reservoir in the Niger delta Basin. Key Words : Depth-Conversion, Velocity-Modelling, Polynomial-Function, Vo_K -Function, Niger- Delta.","PeriodicalId":383706,"journal":{"name":"Journal of the Cameroon academy of sciences","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126052726","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Urbanized landscapes are known to have relatively high atmospheric pollutants due to high concentration of anthropogenic activities. This paper therefore examines the spatial and temporal variations of the physico-chemical properties of rainwater at the core, intermediate and urban fringe of Benin City. Rainwater samples were collected at 2 locations each at the core (Ring Road and Forestry), intermediate (Airport Road and Upper Mission) and urban fringe (Ikpoba Hill and Ogba) in the months of March and July, 2016. The physico-chemical properties of the rainwater differed significantly at the core, intermediate and urban fringe between the months of March and July with t-statistics of 3.029, 3.737 and 2.764 (p < 0.05) respectively. The difference in rainwater properties among the core, intermediate and urban fringe zones were insignificant in the months of March and July. With the exceptions of colour, turbidity, P and Fe in the month of March and P and Fe in the month of July, rainwater properties from the three locations, where WHO guidelines for drinking water is applicable, were within permissible limits. Water quality was excellent at the core, intermediate and urban in the month of July while it was excellent at the intermediate and urban fringe and good at the core in the month of March. Findings suggest that besides the role of rainfall amount in atmospheric cleansing, other factors such as wind profile and direction and atmospheric stagnation also play critical influence on rainwater quality. Keywords : Rainwater, water quality index, physico-chemical properties, Benin City, Nigeria On sait que les paysages urbanises presentent des polluants atmospheriques relativement eleves en raison de la concentration elevee d’activites anthropiques. Cet article examine donc les variations spatio-temporelles des proprietes physico-chimiques de l’eau de pluie a la peripherie centrale, intermediaire et urbaine de Benin City. Des echantillons d’eau de pluie ont ete collectes a deux endroits situes respectivement aux quartiers centraux (Route Peripherique et Foret), intermediaires (Route Aeroportuaire et Upper Mission) et urbains (Ikpoba Hill et Ogba) en mars et juillet 2016. Les proprietes physico-chimiques des eaux pluviales differaient significativement aux franges centrales, intermediaires et urbaines entre les mois de mars et juillet avec des statistiques t de 3,029, 3,737 et 2,764 (p <0,05) respectivement. La difference de proprietes des eaux de pluie entre les zones centrales, intermediaires et urbaines etait insignifiante aux mois de mars et juillet. A l’exception de la couleur, de la turbidite, du P et du Fe au mois de mars et du P et du Fe au mois de juillet, les proprietes des eaux de pluie des trois sites, ou les directives de l’OMS pour l’eau potable sont applicables, etaient dans les limites permises. La qualite de l’eau etait excellente au centre, intermediaire et urbaine au mois de juillet, tandis qu’elle etait excellente a la peripher
由于人类活动的高度集中，城市化景观具有相对较高的大气污染物。因此，本文研究了贝宁市核心、中间和城市边缘地区雨水物理化学性质的时空变化。于2016年3月和7月在核心(环路和森林)、中间(机场路和上使命)和城市边缘(Ikpoba山和Ogba)的2个地点收集雨水样本。3月至7月，城市核心区、中间区和城市边缘区的雨水理化性质差异显著，t统计量分别为3.029、3.737和2.764 (p < 0.05)。3月和7月，核心区、中间区和城市边缘区的雨水特性差异不显著。除了3月份的颜色、浑浊度、磷和铁以及7月份的磷和铁外，这3个地点的雨水特性均在允许范围内，这些地点适用世卫组织饮用水指南。7月份核心区、中间区和市区水质优良，3月份中间区和城市边缘区水质优良，核心区水质优良。结果表明，除了降雨量对大气净化的作用外，风廓线、风向、大气停滞等因素对雨水质量也有重要影响。关键词:雨水;水质指标;理化性质;贝宁市;尼日利亚;本文考察了贝宁城市周边、中心、中介和城市的空间、时间和物理特征的变化。Des echantillons d 'eau de pluie ont ete收集了两个独立的区域，分别为中心区域(Route Peripherique和forest)，中间区域(Route Aeroportuaire和Upper Mission)和城市区域(Ikpoba Hill和Ogba)，以及2016年6月。不同地理位置、中心、中介和城市、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置、地理位置等差异显著(p < 0.05)。不同的地方，不同的地方，不同的中心区，不同的中介和城市，不同的地方，不同的地方，不同的地方，不同的地方，不同的地方，不同的地方，不同的地方，不同的地方。A 'exception of la couleur, A '浊积，A ' P ' et de Fe ' mois de mars, A ' P ' et de Fe ' mois de juillet, A ' les propriites of de pluie de trois sites, A ' les directives of l 'OMS pour l 'eau po饮用水适用，A ' aaient dans限制许可。质量我们de威尼斯是excellente盟中心,intermediaire et urbaine盟月de juillet tandis它是excellente像peripherie intermediaire et urbaine et女佣盟盟中心通过火星。研究结果表明，降水的数量和大气的作用是不同的，降水的特征因素是不同的，降水的方向和大气的停滞是不同的，降水的质量决定因素是不同的。Mots-cles: Eaux de pluie, index de qualite de l 'eau, proprietes physical -chimiques，贝宁市，尼日利亚
{"title":"Spatio-temporal variation of the physico-chemical properties of rainwater in Benin City, Nigeria","authors":"G. Atedhor, A. O. Ayeni, Judith A. Aiyeki","doi":"10.4314/jcas.v14i3.4","DOIUrl":"https://doi.org/10.4314/jcas.v14i3.4","url":null,"abstract":"Urbanized landscapes are known to have relatively high atmospheric pollutants due to high concentration of anthropogenic activities. This paper therefore examines the spatial and temporal variations of the physico-chemical properties of rainwater at the core, intermediate and urban fringe of Benin City. Rainwater samples were collected at 2 locations each at the core (Ring Road and Forestry), intermediate (Airport Road and Upper Mission) and urban fringe (Ikpoba Hill and Ogba) in the months of March and July, 2016. The physico-chemical properties of the rainwater differed significantly at the core, intermediate and urban fringe between the months of March and July with t-statistics of 3.029, 3.737 and 2.764 (p < 0.05) respectively. The difference in rainwater properties among the core, intermediate and urban fringe zones were insignificant in the months of March and July. With the exceptions of colour, turbidity, P and Fe in the month of March and P and Fe in the month of July, rainwater properties from the three locations, where WHO guidelines for drinking water is applicable, were within permissible limits. Water quality was excellent at the core, intermediate and urban in the month of July while it was excellent at the intermediate and urban fringe and good at the core in the month of March. Findings suggest that besides the role of rainfall amount in atmospheric cleansing, other factors such as wind profile and direction and atmospheric stagnation also play critical influence on rainwater quality. Keywords : Rainwater, water quality index, physico-chemical properties, Benin City, Nigeria On sait que les paysages urbanises presentent des polluants atmospheriques relativement eleves en raison de la concentration elevee d’activites anthropiques. Cet article examine donc les variations spatio-temporelles des proprietes physico-chimiques de l’eau de pluie a la peripherie centrale, intermediaire et urbaine de Benin City. Des echantillons d’eau de pluie ont ete collectes a deux endroits situes respectivement aux quartiers centraux (Route Peripherique et Foret), intermediaires (Route Aeroportuaire et Upper Mission) et urbains (Ikpoba Hill et Ogba) en mars et juillet 2016. Les proprietes physico-chimiques des eaux pluviales differaient significativement aux franges centrales, intermediaires et urbaines entre les mois de mars et juillet avec des statistiques t de 3,029, 3,737 et 2,764 (p <0,05) respectivement. La difference de proprietes des eaux de pluie entre les zones centrales, intermediaires et urbaines etait insignifiante aux mois de mars et juillet. A l’exception de la couleur, de la turbidite, du P et du Fe au mois de mars et du P et du Fe au mois de juillet, les proprietes des eaux de pluie des trois sites, ou les directives de l’OMS pour l’eau potable sont applicables, etaient dans les limites permises. La qualite de l’eau etait excellente au centre, intermediaire et urbaine au mois de juillet, tandis qu’elle etait excellente a la peripher","PeriodicalId":383706,"journal":{"name":"Journal of the Cameroon academy of sciences","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128820229","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
L’identite est un systeme caracterise par des processus qui permettent de definir simultanement une representation de soi et du monde social. Elle n’existe qu’a travers un travail permanent de construction, adosse a des niveaux d’ancrage et d’objectivation differents. Ainsi, la presente etude vise a demontrer que dans un contexte socioculturel fortement domine par des dynamiques foncieres et ou les rapports au foncier sont vitaux, l’expropriation, evenement potentiellement riche en affect est susceptible de favoriser des depersonnalisations aupres des expropries. Si de maniere proactive la crise d’identite connote l’idee de perturbations, le processus d’ajustement, de reconstruction et de reorganisation bute le plus souvent, a un ensemble de variables combinees. Ainsi avons-nous opte pour le paradigme systemique comme modele explicatif a laquelle viennent se greffer la theorie de l’engagement, celle de la resistance au changement et enfin la theorie de l’identite sociale. Mots cles : expropriation, crise identitaire, socio territorial
{"title":"Expropriation et crise de l’identite socioterritoriale au Cameroun : Etude menée à lom pangar","authors":"Serge Armand Zang Ndi","doi":"10.4314/jcas.v14i2.5","DOIUrl":"https://doi.org/10.4314/jcas.v14i2.5","url":null,"abstract":"L’identite est un systeme caracterise par des processus qui permettent de definir simultanement une representation de soi et du monde social. Elle n’existe qu’a travers un travail permanent de construction, adosse a des niveaux d’ancrage et d’objectivation differents. Ainsi, la presente etude vise a demontrer que dans un contexte socioculturel fortement domine par des dynamiques foncieres et ou les rapports au foncier sont vitaux, l’expropriation, evenement potentiellement riche en affect est susceptible de favoriser des depersonnalisations aupres des expropries. Si de maniere proactive la crise d’identite connote l’idee de perturbations, le processus d’ajustement, de reconstruction et de reorganisation bute le plus souvent, a un ensemble de variables combinees. Ainsi avons-nous opte pour le paradigme systemique comme modele explicatif a laquelle viennent se greffer la theorie de l’engagement, celle de la resistance au changement et enfin la theorie de l’identite sociale. Mots cles : expropriation, crise identitaire, socio territorial","PeriodicalId":383706,"journal":{"name":"Journal of the Cameroon academy of sciences","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122310696","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Muh Blast Naintoh, M. Wantim, Ayonghe Samuel Ndonwi
Climate change and variability are common phenomena that affect crop productivity globally but with significant differences between different regions of the world. Studies of the impacts of these phenomena on Irish potato –Solanum tuberosum L.-production within Tubah Sub-Division based on records of precipitation and temperatures from 1995 to 2015, indicated an increasing mean annual temperature rate of 0.09 0C per year and a slight increasing annual rainfall rate of 25.8 mm per year. Potato yields within the same period equally increased by 1.26 t/ha per year until 2012 when the yields started decreasing due to a correspondingly marked increase in both temperature and rainfall. The drop in potato yields has also been attributed to disease infestation such as potato blight and rot which are favoured by the increases in temperature and rainfall. Statistical correlation and regression analyses of these data revealed that the potato yields showed weak positive correlations with temperature (R= 0.02) and with rainfall (R= 0.12). Results from questionnaire survey, focus group discussions and semistructured interviews indicated that the potato crop (63 %) of most farmers were negatively affected by climate change and variability through the increased sporadic rainfall which enhanced potato blight and rot. Some adaptation strategies to these climatic factors are already being practised by most farmers (81 %) who are making use of a combination of fertilizers, pesticides, improved seeds and irrigation practices to remedy the situation although further approaches such as the use of resistant species are necessary towards improving on the dwindling potato yields. Keywords : Climate, Change, Variability, Tubah Sub Division, Irish Potato, Adaptation Strategies, Cameroon.
气候变化和变率是影响全球作物生产力的常见现象，但在世界不同区域之间存在显著差异。根据1995 - 2015年的降水和温度记录，研究了这些现象对Tubah小区内爱尔兰马铃薯-Solanum tuberosum l .生产的影响，表明年平均气温增加0.09℃/年，年降雨量略有增加25.8 mm /年。同期马铃薯产量平均每年增加1.26吨/公顷，直到2012年，由于温度和降雨量的显著增加，产量开始下降。马铃薯产量的下降还归因于马铃薯枯萎病和腐病等病害的侵袭，这些病害是由于温度和降雨量的增加而发生的。统计相关分析和回归分析表明，马铃薯产量与温度(R= 0.02)和降雨量(R= 0.12)呈弱正相关。问卷调查、焦点小组讨论和半结构化访谈的结果表明，大多数农民的马铃薯作物(63%)受到气候变化和多变性的负面影响，零星降雨的增加加剧了马铃薯的枯萎病和腐烂病。大多数农民(81%)已经采用了一些适应这些气候因素的策略，他们使用化肥、农药、改进种子和灌溉方法来补救这种情况，尽管需要采用诸如使用抗性品种等进一步的方法来改善日益减少的马铃薯产量。关键词:气候，变化，变异，Tubah分部，爱尔兰马铃薯，适应策略，喀麦隆
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