313 Records out of 22207 Records

The agriculture of the white highlands of Kenya

Author: Hood, C

Awarding University: University of London, England

Level : MA

Year: 1958

Holding Libraries: Institute of Commonwealth Studies Library ;

Subject Terms: Agriculture/Central Province/Rift Valley Province/Colonialism/ ;

Abstract:

ABSTRACT NOT AVAILABLE

Spatial patterns of Kenya agriculture and their relationship to elevation, soils and population : a study of grid cell sizes

Author: Cary, Ernestine//

Awarding University: Columbia University, USA

Level :

Year: 0

Holding Libraries: National Council for Science and Technology Library ;

Subject Terms: Soils ; Agriculture ; Population ; Socioeconomic factors ;

Abstract:

In this research, the relationships of socio-economic and physical factors to patterns of agriculture are investigated to see how assessments of those relationships change with resolution. The study area comprises 7000 square kilometers (2600 square miles) in western Kenya, near the Uganda border. In order to assess quantitatively the relationships of agriculture to other factors, a geographic data base was created. The entire study area was divided into uniform cells, specified in terms of geographic location, and data were stored for each cell. The variables of elevation and soil color (hue, value, and chroma) were digitized from maps, with data recorded for cells covering 100 meters by 100 meters on the ground. For the measure of agricultural patterns, a greenness index was calculated from two spectral bands of landsat data, and associated with the same 100-meter cells. The population data were recorded for 1000-meter cells, from a combination of map and tabular data. Then a cell-by-cell comparison of agriculture (as observed in the field and interpreted from greenness) to each encoded environmental factor was made. The original cells were aggregated, and the same comparison made. Additional cycles of aggregation and comparison then resulted in information about the strength of association as a function of cell size. The present research is a more thorough empirical investigation of the effects of aggregation on correlation than other quantitative studies in four ways: (1) a regular grid of cells was used; (2) more pairs of variables were used; (3) there were more levels of aggregation, and (4) the sample size was larger than in other studies. Analysis of the field observations and the greenness index showed that the greenness index provides a measure which relates to agricultural systems. Comparison of greenness to elevation, soil, and population density at a range of scales showed that the relationship is always strongest with elevation, weakest with population. That is, the use of cells of regular shape and equal size leads to the same assessment of relationships throughout a broad range of scales.

Steering response analysis of an animal-drawn mouldboard plough [Kenya].

Author: Mutua, J M

Awarding University: Cranfield University, England

Level : PhD

Year: 0

Holding Libraries: Index To Theses ;

Subject Terms: Agriculture ; Agricultural machinery ; Performance evaluation ;

Abstract:

The importance of the animal-drawn mouldboard plough in Kenyan small-scale farming sector is reviewed and the operational problems associated with the implement leading to poor seedbed, poor weed control and operator fatigue. The research aims at firstly providing an insight on the dynamic behaviour of the Victory mouldboard plough when responding to a steering input, and secondly, based on the findings of the dynamic behaviour, advises on design and operational criteria aimed at improving the dynamic performance, hence the quality of work and reduced operator fatigue. There are three parts to this research: part one deals with the theoretical analysis. Here the mathematical equations governing the lateral dynamic behaviour of the animal-drawn mouldboard plough are developed. Part two deals with the experimental verification of the theories developed in part one. Extensive experiments were carried out in the soil bin using a fully instrumented Victory mouldboard plough to test its response to a steering input under different set of parameters viz: two hitch lengths, two hitch points and three different sizes of landsides. Part three advises on the operational criteria aimed at improving the lateral stability and steering responses of the plough under different operating conditions