Uwadiegwu Ibeabuchi
Abstract
Soil erosion is one of the major environmental issues which has caused considerable economic damage and still remains an intractable problem in many parts of Abia state. InVEST model was used to map the environmental and economic cost of soil loss by studying: (1.) sediment exported and retained from ...
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Soil erosion is one of the major environmental issues which has caused considerable economic damage and still remains an intractable problem in many parts of Abia state. InVEST model was used to map the environmental and economic cost of soil loss by studying: (1.) sediment exported and retained from soil loss, (2.) nutrient exported and retained from soil loss, and (3.) the resiliency of the hydrological basin to withstand changes from soil and nutrient loss using GIS (Geographic Information System)technique. Estimated total soil loss from sediment export was found to have a higher significant impact on the hydrological basin of Abia state than sediment retained. The model estimated nutrient (Phosphorous and Nitrogen) exported and retained against the economic benefit of nutrient exported and retained as well as the economic value of the basin for retaining nutrient over the specified time span. This found nutrient and economic value lost from sediment export higher than sediment retained. A resilient check was performed on the Abia state basin to ascertain the strength, ability of the basin to spring back into shape and withstand the pressure from on/off-site damage accumulated from soil loss, nutrient loss, and nutrient economic value lost. Abia state basin was found to have a resilient level of 69.20% low and 30.80% high in 1972, 19.63% of very low and 88.88% of low resilient in 1986 and 2003, while in 2015 very low resilient of 39.30% and 60.70% of low resilient. The result reveals a drastic reduction in the resilient level between 1972 and 2015 as well as its agro-productivity, socio economic equalities and overall well-being of Abia sate. This research highlights the fact that proper conservation measures needs to be applied to improve agro productivity, water quality standard and the general well-being of Abia state.
Uwadiegwu Ibeabuchi
Abstract
Change in rainfall is one of the most critical factors in determining the impact of climate change on Abia state. Annual rainfall data was acquired from HadCM3 baseline and future scenarios between 1972 and 2050 for Abia state. Analysis was performed using Geographical Information System (GIS) and statistical ...
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Change in rainfall is one of the most critical factors in determining the impact of climate change on Abia state. Annual rainfall data was acquired from HadCM3 baseline and future scenarios between 1972 and 2050 for Abia state. Analysis was performed using Geographical Information System (GIS) and statistical techniques. Descriptive statistics were extracted using statistical methods while for spatial rainfall distribution, standard deviation and coefficient of variation were mapped using GIS interpolation methods. For baseline scenario between 1972 and 2015, annual rainfall minimum, maximum, mean, variability, standard deviation and coefficient of variation in the southern part of Abia state is relatively higher than the northern part of the state which is lower compared to future scenario between 2015 and 2050. Significant changes in rainfall between 2015 to 2050 in-relation to its distribution pattern (using Log Pearson Type III probability distribution) in-terms of its frequency, climate extremes and extreme events is higher than 1972 to 2015. This change in rainfall implies that in Abia state an increase in heavy rainfall with a 0.2% chance exceedance annual rainfall event is likely to become 0.5% chance exceedance event in many regions with a higher emissions scenarios leading to a greater projected decrease in return period. Finally, water requirement for various crops were studied in-relation to effective rainfall and the results reveals that crops receive a high probability of critical rainfall amount in a given year needed for growth between 1972 and 2050. This study provides information on rainfall trend on a long-term basis and impact of climate change on Abia state which will be very useful for water resource management, agriculture and economic development of the region.
