Characterisation of farming systems in southern Rwanda

III.2 METHODOLOGY

III.2.1.STUDY FRAMEWORK

AGROECOLOGICAL ZONE

Bio-physical

DISTRICT

Bio-physical

VILLAGE

Socio-economic

Poor farmer

Well-off farmer

Middle farmer

Soil fertility factors

Plot 2

Plot 1

Plot 3

Plot 2

Plot 1

Plot 3

Plot 1

Plot 2

Figure 1: Framework

III.2.2. Site selection and characteristics

Shanga location known as a coffee production site with sandy soil was selected as a representative site for our study. It is located at 1780 m of altitude, with latitude of 02⁰ 32'502'' South and 029^o 37' 955'' East. In Shanga, the major food crops grown by the smallholders are beans (Phaseolus Vulgaris), sweet potatoes (Ipomea batata.), sorghum (sorghum ssp) and cassava (Manihot escuenta). In marshland, sweet potatoes and tomatoes are grown especially in dry season while beans, cassava, sweet potatoes and sorghum are planted on the hills. The most earning crops are tomatoes, and cassava sold generally to local market. Main cash crop is coffee. The dominant soil type is clay downhill and sandy soil uphill. Most domestic animal reared in Shanga are generally local cows, goats, pigs, and chickens. Cropping system found is mixed cropping where crops , livestock and trees interact on the farm. Trees found are grevillea providing timber, mulching and bean stakes, avocado papaya, orange and citrus providing fruits. Number of trees on farm depends on the type of farm. Pennisetum grass is also found in most of fields. Majority of farmers use organic matter from animal mixed with crop residues and few use inorganic fertilizers.

III.2.3. Wealth categorization and farmer selection

The process of categorizing farmers was done in different steps. Firstly, a community meeting with local farmers was held to get an overview of all socio-economic situation of the area. Then farmers were asked to self-categorize into wealth groups according to their socio-economic status. Wealth classes were established based on farmer criteria (number of animal and type of animal ownership, type of house, type of farm size...). Farmers' criteria of wealth are mainly the number of cattle. Hence three wealth groups were found: Well-off, Middle, and Poor as synthesize in the following table

Table 2. Criteria used by farmers to categorize themselves in wealth categories

category criteria	RICH (umukungu)		MIDDLE (uwifashije)	POOR (umukene)
LIVESTOCK	2 cattle or more		1 cattle or 3goats/sheep	1 livestock or none
LANDSIZE	1 ha or more		Between 0.5 ha and 1 ha	Small or none
TREES OF COFFEE	1000 or more		Between200 and 500	100 or none
STATE OF HOUSE		Modern cemented house & roof in iron	Modern house in Clay walls	Classic house in clay roofed with grasses
LABOUR		Hire labour	Can hire labour sometimes	Sell labour for cash income
PRODUCTION		Produces enough and sale surplus	Produces enough for his family	Produces not enough for his family

The total number of farmers interviewed was 84.All farmers present in the meeting were self-categorized into three different wealth groups. Rich farmers represented about 13.8% of the community, 33.8% representing moderate farmers and 52.3% representing poor farmers. The total number of households in Shanga cell was 1179. We proceed with determination of representative sample using appropriate mathematical formula.

Number of households: 1179 with á: 10 %

n=no/(1+no/N)

no=(Zá/2)²*(1/2)²/d²

Z(á/2, N-1)=1.64

no=(1.64)²*0.25/(0.1)²=67.24

n = 67.24/ (1 + 67.24/1179) = 64

with

· n: size of sample

· N: size of households (1179)

· no: size of sample for the population

Based on these proportions, a sample of 65 farmers was selected among the community on which a survey was conducted. Therefore, we randomly selected 9 well off farmers, 22 middle farmers and 34 in the third group.