Effect Of Change In Farming Systems On Soil Resource Management In Subukia Sub-County, Kenya

Abstract

The Kenya Vision 2030 is a vehicle for accelerating transformation of Kenya into a rapidly industrializing middle income nation by the year 2030. It therefore recognizes the role of agriculture in ensuring that food insecurity is curbed and a reduction in the number of people receiving food relief throughout the year. An estimated 75 percent of the population depends on the agricultural sector either directly or indirectly. This therefore brings about the issue of soil resource management necessitated by a change in farming systems brought about by preference in some land uses as opposed to others. Land policies are hence important in ensuring that there is adequate implementation of laws that govern sustainable land use change. The objectives of the study were therefore to assess the changes in farming systems for the last three decades, to identify the differences in soil fertility under intensive and extensive farming systems, and to assess implementation of land policies in fostering sustainable land use and enhancing soil fertility. The study used a descriptive survey design where the population of the study was a total of 16,660 households. A sample size of 106 respondents comprising of 100 households and six key informants was used. Stratified random sampling and proportionate sampling were applied. Soil samples were collected from farmers in the three sub-locations based on the type of farming system (intensive or extensive). Surface soil (0-15cm) samples were collected from 18 farms, of which nine were from intensive and the other nine from extensive farms. To assess soil quality, samples were subjected to analysis of selected chemical properties (soil organic carbon, nitrogen, soil pH, phosphorus and potassium) in the laboratory. The data was analyzed using Genstat at five percent level of significance. Data collected using questionnaires was organised through the Statistical Package for Social Sciences (SPSS) and Chi-square statistical test was used to test all the hypotheses at P<0.05 significance level. This study showed that, small scale farming was the xi most predominant land use at 64%, and the least common was large scale farming, having reduced by over 13% in the past three decades. Other land uses which had changed significantly were; urban settlements, water resources and shrub land. More so, 97% of the farmers had adopted extensive farming as opposed to intensive farming. There were no significant differences between intensive and extensive farming systems in terms of soil pH, phosphorus and potassium. However, the two systems differed in terms of soil organic carbon and nitrogen with intensive farming system having more organic carbon and nitrogen. In light of soil fertility management practices adopted by farmers, the use of organic fertilizers was more preferred by over 60% of farmers from both intensive and extensive farming systems, as opposed to inorganic fertilizers. In addition, there are good land use related laws and policies in place, for sustainable soil resource management, but their implementation is ineffective. The study recommends that there is need to educate farmers on sustainable land use and soil fertility management practices to ensure environmental conservation for posterity. In addition, there is need to ensure that there is public sensitization on land use policies from a household level for sustainability