Mapping Urbanization and Analysis of Its Impact on Quantity of Arable Land. A Case Study of Nairobi City County

Abstract

Urbanization has been defined as an inter-sectoral trend that directly encompasses all aspects of human civilization and the economy. One of the major drivers of rapid urbanization in Kenya is demographic dynamics. Urban population in Kenya has been on the rise since the inception of census activities in 1897. Based on KNBS findings, it is projected that by 2050, 55% of the entire country’s population will be living in urban areas. Urbanization has had major influence so far on our landscape with most arable lands, protected areas, riparian reserves and wetlands in Nairobi City County paving way for urban developments. This project employed the use of Remote Sensing and GIS Technologies together with AHP Multi-Criteria decision-making tool in mapping urbanization and analyzing its effect on the quantity of arable land in Nairobi City County. The study delineated and categorized all lands in the county based on their level of suitability for crop farming as Very Highly Suitable, Highly Suitable, Suitable and Low Suitability. Nairobi City County has undergone rapid urbanization in the past two decades. It’s annual rate of urbanization stands at 5.02% as per the findings of this project during the past two decades. This has had a major impact on the quantity of lands potential for crop farming with an approximate 4,514 Hectares of land having been lost to Built-Up Areas in a time span of 18 years i.e. from 2000 to 2018. This clearly highlights the magnitude of the impact that urbanization has had on the quantity of arable land.