Browsing by Author "Odera, Patroba"

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    Open Access
    A remote sensing assessment of irrigation land use land cover change in the Sokoto Rima River Basin, Nigeria
    (2021) Abdulmajid, Aminu; Eckardt, Frank; Odera, Patroba
    This study examines the expansion and utilisation of Fadama irrigation in the Sokoto Rima River Basin using the ground yield and remote sensing data. Decadal land use land cover (LU/LC) change detection was conducted using remotely sensed data from Landsat 4,5,7 ETM for 1988, 1998 and Landsat 8 OLI for 2018 using a digital classification and a cloud-based classification provided by Google Earth Engine (GEE) API, with an overall accuracy of 97% in 1988, 92% in 1998 and 90% in 2018. Additionally, the Normalised Difference Vegetation Index (NDVI) derived from MODIS, GEE NDVI, and the Landsat was used to assess the crop yield patterns of the irrigation farming at the Fadama sites in conjunction with the limited ground yield data from 2000-2005, and was found to be a positive change over the years. The result generated from the classification was juxtaposed with observable field characteristics of the LU/LC identified. The decadal trend between 1988 to 1998 saw an increase of 114% in dam surface water and 166% of the natural vegetation, while the nonvegetated areas and the Fadama areas decreased in size by -100% and -65% respectively. Between 1998 and 2018, the reverse of the previous pattern was observed, with water and vegetated areas decreasing in their surface area in hectares by -80% and -23% respectively. Non-vegetated areas increased by 3% while Fadama areas increased in size by 112%, indicating that the Fadama areas were under-utilised by - 65% of the total hectarage in the past, and in recent years a 47% increase was recorded between the two periods. In addition, the Standardised Precipitation and Evapotranspiration Index (SPEI) data from 1950 was used to analyze the meteorological and hydrological drought pattern at four locations within the basin and was found to be a moderate drought. The SPEI data was then correlated with the Global Surface Water Explorer data to observe the surface water dynamics and to show the drought extent around Bakolori, Goronyo, Jibia, Wurno and Zobe dams. The result showed that the dams are shrinking in size due to risen temperature and consequent evaporation caused by moderate drought and water use for irrigation. Lastly, this research uncovers the utilization of the Fadama in recent years by 47%, but with mismanagement of the resources in the Sokoto Rima River floodplain because not all the irrigation fields are put into cultivation, with 39,907 ha put into use from the planned irrigation of 105,472 ha in the entire basin. Therefore, this research recommends a proper intervention of the government to promote and enhance sustainable management of the Fadama lands, water, and the vegetation resource. This should be done in consideration of the deteriorating climate to close yield gaps, with much emphasis on engaging the local farmers by monitoring yearly ground yield data and ensuring all incentives are distributed effectively to brace an active and sustainable management of the entire basin and its vast resource.
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    Open Access
    Assessment of Hand-held GPS Surveying in Land Adjudication: A Case Study of Ngoliba Settlement Scheme in Kenya
    (JKUAT, 2017-08-02) Odera, Patroba; Jatani, Abdulkadir
    Land adjudication is the process through which existing rights in a particular parcel of land are ascertained. Land ownership in Kenya is largely achieved through a land adjudication process, especially in the rural areas. The Preliminary Index Diagrams (PIDs) are the official map documents that together with adjudication records constitute the adjudication register required for determination and registration of interests and rights over land. The PIDs are produced from enlarged, marked and un-rectified aerial photographs; hence they contain distortions. This paper assesses the application of hand-held GPS surveying to determine plot boundaries in an adjudication area in Kenya. The study was conducted in Ngoliba Settlement schemes. Areas of 12 plots of similar sizes were obtained by three methods - PIDs, traditional ground based surveying using a station-theodolite and EDM (total station) and using a hand-held single GPS (in point positioning mode). Plot areas obtained from PIDs and GPS were compared against those determined from total station measurements, which are taken as the standard in this study. We also compared the coordinates and side lengths derived from total station and handheld GPS measurements. Results show that hand-held GPS can recover 98.1% of the combined area of the 12 plots compared to PIDs which can only recover 77.5%. Results from coordinates and side lengths differences show that hand-held GPS can determine side lengths and coordinates that are approximately close to the ones obtained by total station. Hence Hand-held GPS would significantly improve the accuracy of parcel areas for land adjudication when compared to those obtained from PIDs only.
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    Determination of Suitable Sites for Establishment of Large-Scale Concentrated Solar Power Plants in Kenya
    (Commercial, 2017-01-06) Gathu, Joan; Odera, Patroba; Waithaka, Edward
    The demand for energy in Kenya, especially for electricity, is increasing rapidly due to population growth, decentralization of governance, and technological and industrial development. Hydroelectricity, the core source of power, has proved unreliable due to the rapid climate change. In response, the country has ventured into other renewable sources to counter the issues posed by the alternative nonrenewable sources such as unreliability, high costs, and environmental degradation as seen with the use of diesel and kerosene. The purpose of this research is to determine the viability of setting up a large-scale concentrated solar power plantation in Kenya that will assist in stabilizing Kenya’s energy demand and supply as well as increase its affordability. The project is divided into three phases. The first phase conducts an overlay analysis to determine the Kenya’s solar energy potential. The results show that the northern region has the highest potential. The second step involves the creation of an exclusion mask which eliminates the unsuitable land forms and Land Use Land Cover. Based on the results, the best ten sites are situated in Turkana and Marsabit counties. The final phase involves the evaluation of the potential capacity of power that could be generated per square kilometer. The study finds out that the potential varies based on the technologies: parabolic trough, linear Fresnel reflector, or dish systems.
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    Evaluation of GOCE-based global gravity field models over Japan after the full mission using free-air gravity anomalies and geoid undulations
    (Springer, 2017-09-26) Odera, Patroba; Yoichi, Fukuda
    The performance of Gravity field and steady-state Ocean Circulation Explorer (GOCE) global gravity field models (GGMs), at the end of GOCE mission covering 42 months, is evaluated using geoid undulations and free-air gravity anomalies over Japan, including six sub-regions (Hokkaido, north Honshu, central Honshu, west Honshu, Shikoku and Kyushu). Seventeen GOCE-based GGMs are evaluated and compared with EGM2008. The evaluations are carried out at 150, 180, 210, 240 and 270 spherical harmonics degrees. Results show that EGM2008 performs better than GOCE and related GGMs in Japan and three sub-regions (Hokkaido, central Honshu and Kyushu). However, GOCE and related GGMs perform better than EGM2008 in north Honshu, west Honshu and Shikoku up to degree 240. This means that GOCE data can improve geoid model over half of Japan. The improvement is only evident between degrees 150 and 240 beyond which EGM2008 performs better than GOCE GGMs in all the six regions. In general, the latest GOCE GGMs (releases 4 and 5) perform better than the earlier GOCE GGMs (releases 1, 2 and 3), indicating the contribution of data collected by GOCE in the last months before the mission ended on 11 November 2013. The results indicate that a more accurate geoid model over Japan is achievable, based on a combination of GOCE, EGM2008 and terrestrial gravity data sets.
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    Investigating flood susceptibility and vulnerability through geospatial techniques in Kerala State, India
    (2023) George, Mohan Navya; Odera, Patroba
    A flood is an overflow of water that submerges land that is usually dry. Flooding is a complex phenomenon caused by various meteorological, hydrological, geomorphological, and anthropogenic factors. Flood susceptibility identifies the most vulnerable areas that are flood prone based on the region's physical features. Flood vulnerability is the degree to which people or man-made structures are affected by, or unable to cope with the effects of flooding. One of the key factors in risk management and flood damage assessment is determining flood vulnerability. There has been an increased need to understand floods as they are recurring more frequently. The objectives of this study were to determine the land use/cover changes in Kerala State over the last 45 years, model flood susceptibility for the years 1973, 2001 and 2018 and finally determine flood vulnerability in Kerala for the year 2018. These objectives were achieved through Remote Sensing and GIS techniques. Image classification of Landsat images helped identify the change in land use/cover. The flood susceptibility model was attained by processing the physical characteristics and using the multi-criteria weighted analysis. The flood vulnerability model was achieved by processing the copying, social, infrastructure and physical vulnerability. Again, multi-criteria weighted analysis was used. Results show that in the year 2018, 50.31 % of the area had a medium flood susceptibility and 28.74% of the area had a high susceptibility. The areas of high flood susceptibility and medium flood susceptibility are visually seen to be around the high concentration of built-up area. The high susceptibility regions have only increased since 1973 as the built-up area increased. Regarding flood vulnerability, most of the State (60.59%) had a medium flood vulnerability in 2018, followed by high vulnerability areas taking up 28.48% of the land. The high vulnerability areas are found along the west coast of the State. This study brings awareness that the flood susceptibility regions are increasing year by year and that the State has areas that are highly prone to flood vulnerability. The driving factors behind the increase in flood susceptibility and high flood prone areas are the increase in rainfall, population and the built environment.