Ndop Plain Research Articles

Statistical Farm Records: Drivers and Challenges Among Smallholder Rice Farmers in Ndop Plain, Cameroon

The study seeks to analyze statistical farm records: drivers and challenges among smallholder rice farmers in Ndop Plain, Cameroon. Specifically, to determine the factors influencing smallholder rice farmers in Ndop Plain to keep statistical farm records and to analyze the challenges in the exercise. Methodologically, the study employed primary data collected from some 470 rice farmers using a well-structured questionnaire. Purposive sampling technique was applied to select respondents and a conventional Probit model used to estimate the result. It was observed that: male farmer, level of education, used of records, used of technology to manage statistical farm records, production of different types of rice, use of farm record for input and output analysis, had farm record training and Movement from manual to electronic record keeping are significantly influencing farmers’ statistical farm records practices in Ndop Plain. The challenges observed with record keeping are: fundamental error keeping, bulky records, inadequate finance, records misplacement and burdensome to keep farm records. Considering that only 34% of farmers are involved in records keeping and willing to move from manual way of keeping records to electronic, the study suggests that an online App is created for easy accessibility and inputting of these farm records. This will be a wise-step for the government to scale the process of farm output.

COMMUNITY PARTICIPATION IN THE TREATMENT AND PREVENTION OF ENTEROHELMINTHIASIS OR INTESTINAL WORM INFECTIONS IN CHILDREN BELOW FIFTEEN YEARS IN THE NDOP PLAIN OF THE NORTH WEST REGION OF CAMEROON

This paper seeks to investigate the effectiveness of community participation in the promotion, treatment and prevention of enterohelminthiasis in children from zero to fifteen years in the Ndop plain community. Community participation is premedical in the implementation of PHC system as requested in Alma Ata and the Bamako initiate respectively. To gain knowledge of the phenomenon we conducted a study where we used both the qualitative and quantitative methods of research. The data was collected using a questionnaire, observation and in-depth interview techniques. From the facts gathered and analyzed, we noticed that community participation through community representatives in co-management, public participation in health financing, services of community health workers doesn’t correspond to the realities of rural or community life. This explains why enterohelminthiasis in children especially between the ages of 2-15 years is difficultly controlled. KEY WORDS: Community, Community participation, Enterohelminthiasis, Children below fifteen years

Transhumant Pastoralism and Farmer-Grazier Conflicts in the Ndop Plain, North West Region, Cameroon

This study examines the impacts of rainfall variability on transhumant pastoralist activities and farmer/herder conflicts in the Ndop plain. Using a mixed methods approach, inter-annual rainfall fluctuations, coefficient of variations (CV) were used to establish variability while the rainfall Seasonality was used to identify seasonal contrast. 150 questionnaires were administered to purposively selectednative crop farmers and Mbororo Fulani herders.. The annual rainfall variability is shown by a coefficient of variation of 18.11%, decreasing trend, and a high inter-annual variability around the mean of 1802.95mm. The impacts include; drying up of pasture lands and a fall in the quality of pasture 100%(150), shrinking of river courses and water shortages 84% (126), Outbreak of diseases and pests 88.6%(133), and fluctuations in the transhumant calendar 67.3%(101). The result has been conflicts due to competition over constrained resources and stray animals that destroy crops during transhumance. The stakeholders in this sector need to include climate change communication in this domain and improve rangeland management policies to reflect the state of environmental degradation.

Impact of Rainfall Variability on Maize Production in the NDOP Plain, North West Region of Cameroon (1990-2015)

This study assesses the impact of rainfall patterns from 1990-2015 on maize production in the NDOP Plain of the Bamenda Highlands of Cameroon since maize is a staple food and cash crop in the area. Data on rainfall and maize output were collected from 1990 to 2015 and represented in time series. The rainfall data were further analysed using Rainfall Anomaly Index (RAI), to establish critical periods of rainfall deficiencies. Results indicate that rainfall and maize production trends were increasing from 146.94 mm/month in 1990 to 220.03 mm/month in 2015 and ~0.28 tons/ha in 1990 to ~4.2 tons/ha in 2015 respectively. With uncertainties on the future of the rainfall pattern, the coefficient of variation was 22.03% (unreliable), and farmers should build resilience through agroecology, climate-smart agriculture, conservation agriculture and diversification of production systems.

An Assessment of Water Sourcing Technologies and Stakeholder Stratagems Applied in the Balikumbat Highland Community of Ndop Plain, Cameroon

When a bourgeoning population faces water supply scarcity dilemma, stakeholders and interests emerge to offer multivariate water harvesting systems to affected communities. Stakeholder provision of water resources have deployed varied indigenous and exogenous technologies for domestic uses from natural surface to ground water stores. Community technological prowess and stratagems are functions of relief and climatic traits within a socio-political setting and that is why this paper sets out to assess indigenous and exogenous technologies of stakeholder in community water harvesting systems. Qualitative and quantitative data were collected for water sources, water demands, stakeholders, harvesting systems, technologies of extraction and water management through field observations, questionnaires and interviews. Findings revealed that few inhabitants have exogenous water supply technology and greater proportions depend on low technologies which paradoxically proved to be more sustainable than the high technologies. Stakeholder involvement motifs self-pride and politically driven and so the dearth of village water committees accounting for very derisory participation rates in water sourcing and management. The development and rehabilitation of alternative water sources is vital for sustainable water resource management and not just reliance on technological knowhow in Balikumbat.

Improving Agricultural Productivity and Energy Sufficiency on Marginal Lands: The Agricultural Waste Recycling Approach in the Ndop Ecofarm, North West Region, Cameroon

The Green Revolution, which promotes the extensive use of chemicals for improved productivity has witnessed enormous setbacks. Numerous small poorly equipped and very low-income farmers are unable to gain access to the new production means. As their income opportunities shrink, farmers are left with no options but to tend towards unsustainable activities that depletes the environment more; consequently precipitating the vicious cycle of poverty and environmental degradation characterized by, rising food prices, food security and energy crises. This study used the modified institutional analysis and development framework on the waste recycling approach to review the model for achieving agricultural productivity and energy sufficiency on marginal lands in the Ndop plain North West Region of Cameroon. It specifically analyzed the food and energy benefits alongside potential uptake by small-scale farmers. The results indicated that agricultural waste recycling provided improved market access; generate employment; increase income – increase purchasing power; improve household nutritional security and close the poverty gap (inequalities) amongst the rural poor in the community. Student t-test revealed a significant difference (t=-3.08, P=0.006) of farmers’ livelihood before and after commencing agricultural recycling. Engaging in agricultural waste has enabled 8.5% of farmers to improve their livelihood and enhanced energy efficiency.

Climate Change Evolution and Indigenous Methods of Flood Control in the Upper Nun Valley of Cameroon

This study discusses the evolution of climate change and the use of indigenous methods of flood control in the Upper Nun Valley of Cameroon. The local farmers of the Ndop plain have developed and implemented extensive indigenous farming systems as adaptation strategies to reduce the vulnerability of climate variability over the years. However, these indigenous methods of flood control have not been sustainable enough to guard against severe flood incidences in the Ndop Plain as a result of climate change impact. This paper examines climate change evolution in the region and highlights some indigenous adaptation strategies practised in the Upper Nun Valley and the benefits of integrating such indigenous knowledge into formal climate change adaptation strategies. To ensure stability in food production and sustain food sufficiency in areas where local economies entirely depend on farming and the natural state of the environment, it is important to investigate the indigenous strategies put in place and the extent to which they combat floods in the Ndop Plain. Field surveys, focus group discussions, interviews, participant observation methods and secondary sources were used to collect data from selected villages where rice cultivation and market gardening products are on the increase. Based on climatic data for the region, the simple forecasting method using the forecasting line was used to predict future changes in climatic conditions for the region and the extent to which they may cause floods. The data collected were analyzed in both qualitative and quantitative terms to provide information for the discussion. The results reveal that changes in temperature and rainfall have altered the climatic conditions of the region leading to increased flood incidences in the Plain. The paper posited that a sustainable adaptation mechanism should take into consideration the widening of the drains as well as minimizing the cultivation of crops on the drains which serve as gateways to excessive water into the rice fields. The study also recommends the need to incorporate indigenous knowledge into climate change policies that can lead to the development of effective adaptation strategies that are cost-effective, participatory and sustainable.

Bionomics and vectorial role of anophelines in wetlands along the volcanic chain of Cameroon

BackgroundThe epidemiological profiles of vector-borne diseases, such as malaria, are strongly associated with landscape components. The reduction of malaria burden in endemic and epidemic regions mainly depends on knowledge of the malaria-transmitting mosquito species, populations and behavioural characteristics, as well as malaria exposure risks. This work aimed at carrying out a holistic study in order to characterise Anopheles species in relation to human malaria in seven wetlands along the lower section of the volcanic chain of Cameroon.ResultsEight malaria vectors: Anopheles arabiensis, An. coluzzii, An. funestus (s.s.), An. gambiae, An. hancocki, An. melas, An. nili and An. ziemanni, were found biting humans. Anopheles gambiae was widespread; however, it played a secondary role in the Ndop plain where An. ziemmani was the primary vector species (79.2%). Anophelines were more exophagic (73.6%) than endophagic (26.4%), showing a marked nocturnal activity (22:00–4:00 h) for An. coluzzii and An. gambiae while An. funestus (s.s.) was mostly caught between 1:00 and 6:00 h and An. ziemanni having an early evening biting behaviour (18:00-00:00 h). Female Anopheles were mostly observed to have relative high parity rates (≥ 70%), with the exception of the Meanja site where species parity varies from 46 to 55%. Overall, the transmission level was low with entomological inoculation rates estimated to 0.7 infected bites per person per month (ib/p/mth) in Tiko and Ndop, 1.4 ib/p/mth in Mamfe and 2.24 ib/p/mth in Santchou.ConclusionsThe present study represents detailed Anopheles vector characterisation from an understudied area along the volcanic chain of Cameroon with endemic malaria transmission. The significant differences in bionomics and Anopheles species distribution within the studied wetlands, highlights the importance of providing baseline data and an opportunity to assess the outcome of ongoing malaria control interventions in the country.

Community-Based Approach in the Prevention and Management of Flood Disasters in Babessi Sub-Division (Ndop Plain, North West Cameroon)

Flood is a recurrent natural disaster that has caused enormous human and material damage in many places and continues to hit local committees at an alarming rate. The need to setup permanent committees to prevent and manage flood disasters by local communities is therefore indispensable. In rural areas, the creation of such a structure is always a welcome relief to flood victims but it is often marred by numerous management problems. This study aimed to analyze the community-based approach in the prevention and management of flood disasters in Babessi Subdivision (North West Cameroon), to identify the causes of flood disasters and the preventive strategies used by this local community. A total number of 300 questionnaires as well as structured interviews were used to collect data in the field and the data were analyzed by simple descriptive statistics. The main results revealed that the main cause of flood disasters is heavy and consistent rainfall. Also, poor refuse disposal and drainage system management contribute to floods. The identification of areas likely to be affected by floods and preventing the riparian population from constructing houses along these areas especially beside the main rivers are the flood preventive measures adopted by the local flood management committee. The flood victims are reluctant to relocate to the settlement site earmarked by the Government, meanwhile, the local flood committee do not have the legal tools to forcefully relocate them. The population of Babessi needs to be sensitized on the impending dangers of flood hazard and be encouraged to participate in implementing the adopted strategies to prevent and manage subsequent flood disasters.

The Ndop plain clayey materials (Bamenda area – NW Cameroon): Mineralogical, geochemical, physical characteristics and properties of their fired products

The physicochemical, mineralogical and technological properties of clayey materials from the Ndop plain (NW Cameroon) have been investigated, for their ceramic applications. The clayey materials have mixed facies with colour ranging from brown, grey, mottled and yellowish brown. The thickness of the exploitable clay layer is more than 5 m. Their mineralogical constituents are quartz, kaolinite, illite and feldspars, with kaolinite as major clay mineral. Based on the geochemistry, their source rocks might be felsic, with a mafic rock inference. These materials display high percentage in fine particles and high Atterberg limits. For all the firing temperatures, flexural strength (1.2–11 MPa), water absorption (8.03–24.27%), linear shrinkage (2.10%), weight loss (4.88–16.54%) and bulk density (1.57–2.03 g/cm3) indicate good ceramic properties for firing samples between 900 and 1100 °C. Most of the fired test bricks show a brick red colour with good to very good cohesion. The studied clays were thus, suitable as raw materials for roof tiles, light weight blocks and hollow bricks; however, mixing of high clayey and highly silty materials could improve the quality of the products.

Geohazards (floods and landslides) in the Ndop plain, Cameroon volcanic line

AbstractThe Ndop Plain, located along the Cameroon Volcanic Line (CVL), is a volcano-tectonic plain, formed by a series of tectonic movements, volcanic eruptions and sedimentation phases. Floods (annually) and landslides (occasionally) occur with devastating environmental effects. However, this plain attracts a lot of inhabitants owing to its fertile alluvial soils. With demographic explosion in the plain, the inhabitants (143,000 people) tend to farm and inhabit new zones which are prone to these geohazards. In this paper, we use field observations, laboratory analyses, satellite imagery and complementary methods using appropriate software to establish hazard (flood and landslide) maps of the Ndop Plain. Natural factors as well as anthropogenic factors are considered.The hazard maps revealed that 25% of the area is exposed to flood hazard (13% exposed to high flood hazard, 12% to moderate) and 5% of the area is exposed to landslide hazard (2% exposed to high landslide hazard, 3% to moderate). Some mitigation measures for floods (building of artificial levees, raising foundations of buildings and the meticulous regulation of the flood guards at Bamendjing Dam) and landslides (slope terracing, planting of trees, and building retaining walls) are proposed.

Shallow groundwater recharge mechanism and apparent age in the Ndop plain, northwest Cameroon

Knowledge of groundwater recharge and apparent age constitutes a valuable tool for its sustainable management. Accordingly, shallow groundwater (n = 72) in the Ndop plain has been investigated using the stable isotopes of oxygen (18O) and hydrogen (2H or D) and tritium (3H) to determine the recharge process, timing and rate of recharge, and residence time. The shallow groundwater showed low variability in δ18O values (−2.7 to −4.1 ‰) and 3H content (2.4–3.1 TU). The low variability suggests a similar origin, homogenous aquifer, good water mixing and storage capacity of the groundwater reservoir. Like surface water, a cluster of groundwater along the Ndop Meteoric Water Line (NMWL) and Global Meteoric Water Line indicates meteoric origin/recharge. The rainfall recharge occurs under low relative humidity conditions and negligible evaporation effect. About 80 % of the recharge is from direct heterogeneous/diffuse local precipitation at low altitude (<1,260 m) within the Ndop plain. Approximately 20 % is from high altitude precipitation (localised recharge) or is recharged by the numerous inflowing streams and rivers from high elevations. A homogenous cluster of δ-values in groundwater (and surface water) between May and June monsoon rains on the NMWL suggests dominant recharge during these months. The recharge represents at least 16 % (>251 mm) of the annual rainfall (1,540 mm) indicating high annual recharge; high enough for development of the groundwater resource for agriculture. The 3H content (>2.4 TU) in groundwater indicates post-1952 recharged water with an estimated residence time <30 years, suggesting short subsurface circulation, and subsequently a renewable aquifer.

Hydrochemical and isotopic characteristics of groundwater in the Ndop plain, northwest Cameroon: resilience to seasonal climatic changes

Shallow groundwater (>30 mbgl) is an essential source of drinking water to rural communities in the Ndop plain, northwest Cameroon. As a contribution to water management, the effect of seasonal variation on the groundwater chemistry, hydrochemical controls, drinking quality and recharge were investigated during the peaks of the dry (January) and rainy (September) seasons. Field measurements of physical parameters were preceded by sampling 58 groundwater samples during both seasons for major ions and stable isotope analyses. The groundwater, which was barely acidic (mean pH of 6) and less mineralised (TDS Ca2+ > Mg2+ > K+ and Na+ > Mg2+ > Ca2+ > K+ in the dry and rainy seasons, respectively, but that of anions (\( {\text{HCO}}_{3}^{ - } \) > \( {\text{NO}}_{3}^{ - } \) > Cl− > \( {\text{SO}}_{4}^{2 - } \) > F−) was similar in both seasons. This suggests a negligible effect of seasonal variations on groundwater chemistry. The groundwater, which was CaMgHCO3 and NaHCO3, is chemically evolved rainfall (CaMgSO4Cl) in the area. Silicate mineral dissolution and cation-exchange were the main controls on groundwater chemistry while there was little anthropogenic influence. The major ions and TDS concentrations classified the water as suitable for human consumption as per WHO guidelines. The narrow cluster of δ18O and δD of same groundwater from both seasons between the δ18O and δD values of May–June precipitation along the Ndop Meteoric Water Line indicates meteoric origin, rapid recharge (after precipitation) and timing of recharge between May and June rainfall. Diffuse groundwater recharge mainly occurs at low altitudes (<1,400 m asl) within the plain. Besides major ions and TDS, the similar δ18O and δD of groundwater from both seasons indicate a consistent groundwater recharge and flow pattern throughout the year and resilience to present day short-term seasonal climatic variations. However, controlled groundwater abstraction is recommended given the increasing demand.

Origin of major ions in monthly rainfall events at the Bamenda Highlands, North West Cameroon

Rainwater characteristics can reveal emissions from various anthropogenic and natural sources into the atmosphere. The physico-chemical characteristics of 44 monthly rainfall events (collected between January and December 2012) from 4 weather stations (Bamenda, Ndop plain, Ndawara and Kumbo) in the Bamenda Highlands (BH) were investigated. The purpose was to determine the sources of chemical species, their seasonal inputs and suitability of the rainwater for drinking. The mean pH of 5 indicated the slightly acidic nature of the rainwater. Average total dissolved solids (TDS) were low (6.7 mg/L), characteristic of unpolluted atmospheric moisture/air. Major ion concentrations (mg/L) were low and in the order K+ > Ca2+ > Mg2+ > Na+ for cations and NO3− ≫ HCO3− > SO42− > Cl− > PO43− > F− for anions. The average rainwater in the area was mixed Ca-Mg-SO4-Cl water type. The Cl–/Na+ ratio (1.04) was comparable to that of seawater (1.16), an indication that Na+ and Cl– originated mainly from marine (Atlantic Ocean) aerosols. High enrichments of Ca2+, Mg2+ and SO2–4 to Na+ ratios relative to seawater ratios (constituting 44% of the total ions) demonstrated their terrigenous origin, mainly from Saharan and Sahelian arid dusts. The K+/Na+ ratio (2.24), which was similar to tropical vegetation ash (2.38), and NO3– was essentially from biomass burning. Light (< 100 mm) pre-monsoon and post-monsoon convective rains were enriched in major ions than the heavy (> 100 mm) monsoon rains, indicating a high contribution of major ions during the low convective showers. Despite the acidic nature, the TDS and major ion concentrations classified the rainwater as potable based on the WHO guidelines.

Monthly δ18O, δD and Cl− characteristics of precipitation in the Ndop plain, Northwest Cameroon: Baseline data

Knowledge of stable isotopes and chemical tracers in meteoric water has been used as a valuable tool in various environmental studies. A systematic monthly sampling of precipitation, in the Ndop plain, was carried out to generate basic data on δ18, δD and Cl−, determine their seasonal variations and controlling factors to be used as baseline data in hydrological and climatological studies. The δ18O–δD relationship of rainfall gives a regression line: δD = 7.93 δ18O + 13.26 (R2 = 0.99), which represents the Ndop Meteoric Water Line (NMWL). The slope is similar to the Global Meteoric Water Line (GMWL), but, with a high d-excess, which suggests a contribution of continental recycled moisture to precipitation. Precipitation shows a wide variation, throughout the year (2012) in δ18O and δD, from +3.86 to +38.62‰ in January to −7.98 and −53.18‰ in September, respectively. The volume-weighted mean of precipitation, which plots close to June rainfall, is −5.61‰ and −31.93‰ for δ18O and δD, respectively. Light convective pre-monsoon and post-monsoon showers, under low relative humidity conditions, are isotopically more enriched than heavy orographic monsoon rain, under high relative humidity conditions. Chloride varies from 1.56 mg/l in the pre-monsoon to 0.06 mg/l during the monsoon rains; like δ18O and δD, it shows high values in early and late rains. Apart from January, all d-excess values in monthly rains are >10‰. The high d-excess values at the beginning and end of the rainy season suggest the contribution of recycled moisture to precipitation during these periods, under low relative humidity conditions. Assuming a constant condensation temperature, the observed seasonal variation in isotopic composition of precipitation is probably as a result of the (1) rain out of Atlantic moisture, (2) monthly rainfall amounts, (3) addition of inland recycled moisture, (4) rain formation mechanism, and (5) varied relative humidity. The varied Cl− concentrations are due to anthropogenic and oceanic sources, and rainfall amounts.

English

&nbsp; This study was conducted on the hydrochemistry of shallow groundwater and surface water in the Ndop plain, North West Cameroon. The objectives were to determine the physico-chemical characteristics of water, controls on water chemistry and suitability for drinking and irrigation. Forty-six shallow groundwater and 26 surface water samples were investigated. Field measurements of physical parameters were preceded by chemical analyses of the samples for major ions and F-.&nbsp;About 69% of the water sources had pH values below 6.5, classifying the water as barely acidic. Electrical conductivity (&lt;282 &micro;S/cm) and total dissolved solids (&lt;183 mg/l) were low suggesting low-mineralised and freshwater. The relative abundance of major ions (meq/l) was Na2+&gt;Ca2+&gt;Mg2+&gt;K+&nbsp;for cations and HCO3-&gt;&gt;NO3-&ge;Cl-&gt;SO42-&nbsp;for anions. Major ion concentrations were low, and within the WHO guidelines for drinking water, but F-concentrations were much lower (&lt;0.39 mg/l) and below guideline value. Main water types and proportions were Na-HCO3&nbsp;(53 %), Ca-HCO3&nbsp;(35 %) and a mixed Na-Ca-HCO3&nbsp;(11%). Predominant processes influencing water chemistry were incongruent dissolution of silicate minerals and cation-exchange of Na+&nbsp;in rocks for Ca2+&nbsp;in water. The low major ion concentrations indicated low water-rock interactions and short residence time. The analysed water was suitable for irrigation. &nbsp; Key words:&nbsp;Water chemistry, hydrochemical controls, drinking-irrigation quality, Ndop plain, Cameroon.

Epidemiology of Burkitt’s lymphoma in Northwest Province, Cameroon, 2003–2010

Background: Burkitt’s lymphoma (BL) is an aggressive non-Hodgkin’s lymphoma endemic to regions of Africa. Cases are thought to be typically found in low-lying, humid regions where malaria is rife.Aims and Objectives: To investigate the clinical characteristics of BL, its incidence and relationship with malarial incidence in Northwest (NW) Province, Cameroon.Methods: Data on BL were collected from the three tertiary referral centres for BL treatment in NW Province, Cameroon. Data on malaria were collected from the Delegation of Public Health in Bamenda, NW Province. Data were collected between March and May 2010.Results: 471 cases of BL were identified. The St Jude’s stage of patients at presentation was as follows: stage I, 14·4% (43/299); stage II, 8·4% (25/299); stage III, 69·9% (209/299); stage IV, 7·4% (22/299). The incidences of BL per 100,000 children <15 years of age from 2005 to 2009 were as follows: 2005, 3·01 (29); 2006, 2·02 (20); 2007, 2·45 (25); 2008, 2·38 (25); 2009, 3·06 (33). The average incidence in NW Province was 2·58. In the Ndop plain, Ngo-Ketunjia, the incidences of BL were as follows: 2005, 10·3 (10); 2006, 3·00 (3); 2007, 1·95 (2); 2008, 2·84 (3); 2009, 4·60 (5). The average incidence was 4·54/100,000 children <15 years of age. Statistical analysis demonstrated a sinusoidal distribution of malaria cases throughout the year (P<0·00), with a peak incidence on 10 April. Conversely, no sinusoidal distribution of BL cases was demonstrated throughout the year (P = 0·09).Conclusion: No relationship was demonstrated between an acute malarial infection and BL. Significant clustering was found, with the low-lying Ndop plain of Ngo-Ketunjia having an incidence of BL nearly twice that elsewhere in the region. The study demonstrates that the incidence of BL in NW Province, Cameroon remains one of the highest documented in the world.

Promising Cold-Tolerant and High-Yielding Rice Lines for Ndop Plain, Northwest Cameroon

Promising Cold-Tolerant and High-Yielding Rice Lines for Ndop Plain, Northwest Cameroon

Yield Potential of Irrigated IR7167-33-2-3 and Tainan V At Ndop Plain

Yield Potential of Irrigated IR7167-33-2-3 and Tainan V At Ndop Plain

Yield Potential of IR7167-33-2-3 and Tainan V At Ndop Plain, Northwest Cameroon

Yield Potential of IR7167-33-2-3 and Tainan V At Ndop Plain, Northwest Cameroon