Bancy Mati - Academia.edu (original) (raw)

Papers by Bancy Mati

International Journal of Agronomy, 2014

Effects of change in weather conditions on the yields of Basmati 370 and IR 2793-80-1 cultivated ... more Effects of change in weather conditions on the yields of Basmati 370 and IR 2793-80-1 cultivated under System of Rice Intensification (SRI) in Mwea and Western Kenya irrigation schemes were assessed through sensitivity analysis using the Ceres rice model v 4.5 of the DSSAT modeling system. Genetic coefficients were determined using 2010 experimental data. The model was validated using rice growth and development data during the 2011 cropping season. Two SRI farmers were selected randomly from each irrigation scheme and their farms were used as research fields. Daily maximum and minimum temperatures and precipitation were collected from the weather station in each of the irrigation schemes while daily solar radiation was generated using weatherman in the DSSAT shell. The study revealed that increase in both maximum and minimum temperatures affects Basmati 370 and IR 2793-80-1 grain yield under SRI. Increase in atmospheric CO 2 concentration led to an increase in grain yield for both Basmati and IR 2793-80-1 under SRI and increase in solar radiation also had an increasing impact on both Basmati 370 and IR 2793-80-1 grain yield. The results of the study therefore show that weather conditions in Kenya affect rice yield under SRI and should be taken into consideration to improve food security.

Water Practice & Technology

Drought assessment is necessary for creating adaptation and resilience measures for the livelihoo... more Drought assessment is necessary for creating adaptation and resilience measures for the livelihoods of the affected communities. This study assessed drought trends in Kenya's Upper Ewaso Ng'iro River Basin (UENB) from 1981 to 2020. A Standardized Precipitation Index (SPI), a precipitation-based index, and a Standardized Precipitation Evapotranspiration Index (SPEI), a multivariate index that considers the difference between precipitation and potential evapotranspiration (PET), were used to evaluate drought severity and frequency over varying timescales. Monthly rainfall and temperature data for 10 stations within the basin were analyzed to calculate the SPI and SPEI time series values for 3, 6, and 12 months. The results demonstrate an alarming increase in the severity and frequency of drought events in the UENB since 1999. Additionally, the study reveals that the SPI and SPEI indices differ in identifying temporal and spatial drought characteristics, with longer timescales ...

Journal of Agricultural Science and Technology, Jul 6, 2021

Lake and reservoirs have significant global function as a source of fresh water and they sustain ... more Lake and reservoirs have significant global function as a source of fresh water and they sustain various activities such as agriculture, fisheries, and recreation. They play a critical role in distributing spatially and temporally the meagre water resources in most watersheds. However, the design lifespans of reservoirs are being threatened by volume loss despite their critical role in development. Being able to regularly monitor this volume loss is an important aspect of reservoir sustainable management. In this paper, we present a method that combines dual echo sounding and Geographic Information System (GIS) in bathymetric survey to determine the current volume of Ruiru reservoir in central Kenya. In the reservoir, we showed that the current volume is 2,564,590 m 3 compared to the original volume of 2,980,000 m 3 , which implies that the reservoir has lost about 14% of its recorded volume. Furthermore, the study established, the Depth- Surface Area - Volume relationships, i...

In Kenya, rice is the third most important cereal after maize and wheat, but it is rapidly gainin... more In Kenya, rice is the third most important cereal after maize and wheat, but it is rapidly gaining in popularity. The current paddy system of rice production in Mwea depends on a continuous supply of water for irrigation. However, challenges such as competition for water among farmers within and outside the irrigation scheme result in reduced yields. To meet the demand with the limited water resources in a sustainable way, new innovative ways of rice crop production are needed. SRI is an innovation that offers an opportunity to reduce water demand accompanied by yield increases of rice. This book presents results after a study on SRI practices, particularly a combination of transplanting quickly one young seedling per hill, alternate wetting and drying, and wider spacing between plants, and their effects on plant growth and subsequently on grain yield, water productivity and benefit-cost ratio. Application of a model to assess these effects on rice was the first in Kenya. The reason...

A detailed farm survey was conducted in Mwea Irrigation Scheme, Kenya during the 2010/2011 and 20... more A detailed farm survey was conducted in Mwea Irrigation Scheme, Kenya during the 2010/2011 and 2011/2012 main growing seasons to quantify the benefits of System of Rice Intensification (SRI) over farmer Practice (FP) of rice cultivation. Data was collected through distribution of questionnaires and structured interviews to farmers practicing both SRI and FP methods of rice production on their farms. For SRI practice, factors considered were transplanting one seedling per hole aged 8-15 days at a spacing of at least 20cm by 20cm, weeding the crop at least three times at an interval of ten days and intermittently irrigating the farms. Use of organic manure and weed control method were not major considerations in this study since availability of manure and mechanical weeders were challenges at the time of study. A total of 40 farmers from 10 units out of the 50 SRI farmers from 18 units were sampled. The cost-benefit analysis was estimated using tabular analysis of all the variabl...

Physical Sciences Reviews

The high prevalence of dental fluorosis and bone mineralization deficiency as a result of exposur... more The high prevalence of dental fluorosis and bone mineralization deficiency as a result of exposure to fluorides has increased in Kenya over the years due to consumption of water with elevated levels of fluoride. The World Health Organization (WHO) provides a guideline of 1.5 mg/L level of fluoride in drinking water. However, majority of studies carried out in Kenya over the last 40 plus years have indicated very high levels of fluoride in drinking water in various regions, with a prevalence in dental fluorosis observed in children and adults living in Rift valley and central regions due to basaltic and volcanic rocks. Unfortunately, this trend of fluoride-induced enamel changes has been observed in other regions such as Nairobi and Machakos which were originally presumed to contain low fluoride levels. This study sought to analyse the applicability of Maerua subcordata root powder (MSRP) in the removal of fluorides in borehole drinking water. Fresh Maerua subcordata roots were peele...

De Gruyter eBooks, Mar 6, 2023

Agricultural Water Management, 2023

Farmer-led irrigation development (FLID) is not a new phenomenon and has been happening througho... more Farmer-led irrigation development (FLID) is not a new phenomenon and has been happening throughout the centuries in all countries where irrigation is practised. Despite this, planners, policy makers, funders, including engineers have generally taken the perception that irrigation development occurs mainly in “irrigation schemes”. Although farmer-led irrigation happens in formal irrigation schemes, there is a substantive amount of irrigation development implemented quietly by self-motivated individual farmers on their own initiatives. Such irrigation remains unrecognized, un-recorded and thus ignored in the realm of the irrigation sector decision-makers. The term FLID was coined just recently in 2017, and through it, there is emerging a wealth of knowledge on the technologies, practices, economic, marketing, financing and social components regarding how this sub-sector operates. Indeed FLID is not tacitly captured in Kenya’s policies, statutes and development plans. Its extent is largely unknown since it has not been targeted in any mapping exercise. Yet, as irrigation transitions more from public to private investment, FLID is the next big thing pushing the growth of irrigation in Kenya. This paper therefore highlights some of the salient features of FLID, a sub-sector of interest towards enhancing irrigation development and food security in Kenya.

Raw climate data from ground-based stations as available and shareable for selected stations in t... more Raw climate data from ground-based stations as available and shareable for selected stations in the Simiyu River Watershed, Tanzania.

Reanalysis climate data and aggregated streamflow data from river gaging stations as available an... more Reanalysis climate data and aggregated streamflow data from river gaging stations as available and shareable for the Sasumua River Watershed, Kenya.

Land use change has a major influence on the capacity of watersheds to produce watershed services... more Land use change has a major influence on the capacity of watersheds to produce watershed services such asimproving water quality and flood mitigation. The objective of this study was to simulate the effect of land usechange on the sediment and water yield in Sasumua watershed, Kenya using SWAT model. The SWAT modelwas calibrated and validated using recorded reservoir data. The validated model was then used to simulatewater and sediment yield under three scenarios of runoff curve number CN (improved land surface conditionCN-6, base case, degraded land surface condition CN+ 6). The CN was used as a surrogate to represent landsurface treatments that influence generation of surface runoff following rain events. The coefficient ofdetermination from the calibration of the model was 0.6 and 0.5 for the validation. An increase in CN by 6(scenario CN+ 6) units in the agricultural part of the watershed, increased the sediment loading to the streamsby 53.6% while a reduction by 6 units (scenar...

The water flows of Burguret River, located on the slopes of Mt. Kenya in Burguret catchment, were... more The water flows of Burguret River, located on the slopes of Mt. Kenya in Burguret catchment, were assessed along the profile to determine the water abstraction status. Downstream water users are faced with challenges of low river flows or no flows during the dry season which leads to a lot of conflicts arising due to the water allocation in these areas. Methods used for assessment of water abstraction included field survey visit to ascertain abstraction points details, the water users’ interviews in which convenience and random sampling methods were used. Flow duration curves, fdcs were developed from the observed river flow discharge to ascertain the water supply of Burguret River and finally Mike Hydro model was used to predict optimal flows for water allocation within Burguret catchment. Majority of upstream abstractions used gravity pipes and abstracted large amounts, 14,502 m-3day (67%) of water compared to downstream users who mostly used portable pumps and abstracted 2,696 m-...

Integrated Watershed Management in Rainfed Agriculture, 2011

Journal of Arid Environments, 2000

The effect of climate change on maize production in the semi-humid and semi-arid, agro-climatic z... more The effect of climate change on maize production in the semi-humid and semi-arid, agro-climatic zones III-IV of Kenya was evaluated using two General Circulation Models (GCMs): the Canadian Climate Center Model (CCCM) and the Geophysical Fluid Dynamics Laboratory (GFDL), as well as the CERES-Maize model. Long-term climate data was obtained from three meteorological stations situated in eastern, central and western regions of Kenya, while maize data was obtained from six sites within the regions. The climate scenarios were projected to the year 2030. Temperature increases of 2)29 and 2)893C are predicted by the CCCM and GFDL, respectively. Rainfall levels are predicted to remain unchanged, but there are thought to be shifts in distribution. It is predicted that the short-rains season (October}January) will experience some increased rainfall, while the long-rains season (April-July) will show a decrease. Maize yields are predicted to decrease in zone III areas, while an increase is predicted in zone IV areas. However, the predicted changes in yields are low since they all fall below 500 kg ha\, except the Homa Bay site. Thus, to counter the adverse effects of climate change on maize production, it may be necessary to use early maturing cultivars, practice early planting, and in eastern Kenya, shift to growing maize during the short-rains season.

iscram.org

... 5. Holmern T., Johannesen BA , Mbaruka J., Mkama S.,Muya J. and Røskaft E. (2004) Human-Wildl... more ... 5. Holmern T., Johannesen BA , Mbaruka J., Mkama S.,Muya J. and Røskaft E. (2004) Human-Wildlife Conflicts and Hunting in the Western Serengeti, Tanzania. Norwegian Institute for Nature Research. ... Ojima, DS, 1994. The Global Impact of Land-use Change. Bioscience. Vol. ...