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5. The Ukambani region of Kenya

The Ukambani study area
The history of settlement, land use, and environment (1890-1990)
The trajectory of change in Ukambani
References

Dianne Rocheleau, Patricia Benjamin, and Alex Diang'a

Regional environmental change in the dry farmlands of Kenya represents a microcosm of the processes at work in the savanna and dry forest landscapes of East Africa (and much of southern Africa as well). For global-change studies in particular, Kenya's dry farmlands provide a valuable lesson for the future of the larger region and the planet. Many other nations are encouraged to strive for the economic and resource-management standards that Kenya has already attained, yet the arid and semi-arid farmlands of Kenya suffer from multiple environmental problems associated with land-use change and development itself (Darkoh 1989; Deacon and Darkoh 1987; Mbithi and Wisner 1973). These problems, in turn, will affect and be affected by larger global processes. The dryland farming regions throughout Kenya epitomize the codetermination of economic and ecological change within and among local, regional, and global systems.

The well-documented case of the Akamba people in eastern Kenya provides particular insight into both the substance and process of regional environmental change. Ukambani, the traditional home of the Akamba, is now largely contained within the borders of Machakos and Kitui districts in Kenya (fig. 5.1). The combined area of the two districts is approximately 45,000 km², although one-fifth of Kitui, some 6,300 km², lies within Tsavo National Park and is therefore unavailable for use by the Akamba. More than 95 per cent of the Machakos/Kitui population is Akamba (Porter in prep.; Republic of Kenya 1980; Tiffen 1991a,b,c), and approximately 85 per cent of all Kamba speakers reside in Ukambani (Porter in prep.).

The region regularly recurs as a "classic example" of land degradation in accounts dating back to the 1930s (e.g. Dregne, 1990, 434; Hall 1938, 396; Matheson and Bovill 1950, 218), and state policies have continuously been devised to address this concern. Rural residents report frequent crop failures and water shortages, and food relief has become a permanent feature of rural life (Porter in prep.). A community leader in a semi-arid part of Kitui District, for example, classified 51 per cent of the years from 1947 to 1979 as "bad" or "very bad" famine years (Jaetzold and Schmidt 1983, C213). The Machakos District was a net importer of maize for 14 of the years between 1942 and 1962 for which data are available, and for 8 of the years from 1974 to 1985 (Mbogoh 1991). The ever-present need for food relief has been variously attributed to overpopulation and environmental degradation, to colonization and development, or to insufficient development.

The story of the Akamba people and their lands provides important lessons about the interaction of environmental change with state policy, especially the impacts of sedentarization, privatization, and the commercialization of agriculture, on rapid demographic change (numbers, composition, and distribution of population within the region). The most significant changes in land use at regional scale have included: the movements of highland Akamba to dryland areas, an ongoing land survey and tenure reform, a gradual shift from agropastoral to mixed farming production systems, the continuing conversion of dry forest and savannas to agriculture, the progressive replacement of subsistence by commercial production from household to regional level, the "mining" of dry forest and savanna trees for commercial charcoal markets in the city, and the quarrying of sand from dry river-beds and channels to construct new housing and commercial buildings in the city.

Fig. 5.1 The Ukambani area of Kenya

Both intensive gardens and frontier expansion constitute increasingly important features in the landscape of Ukambani. Concurrent with these visible changes in the landscape, a restructuring of labour has brought many people into the wage labour force, resulting in a new spatial division of labour between men and women in households with rural roots and urban branches. These processes have converged to make the land and people of the region more vulnerable to economic and ecological stress, or more dependent on external market forces and the state. Throughout the drier zones of the region in particular, people describe the degradation of soil, water, flora, and fauna and report crop failures due to drought or pests in four to six seasons out of every ten.

Ukambani constitutes an endangered region as defined in chapter 1, assuming that the area remains non-industrial and rural for the foreseeable future. That is, under the current and foreseeable circumstances of nature-society interaction, land and water degradation threatens the health and livelihoods of the people of the region, and some of the degradation that has already occurred is irreversible. It is important in this case to note the striking variability in the conditions within the region and the very high uncertainty about the future directions and magnitude of environmental change. The central lessons of Ukambani over the last 100 years combine the changing nature and perception of environmental change over time with the distinct experience of those changes across different scales of analysis and between different groups of people.

The more detailed geography and history of environmental change in Ukambani presented below is derived from a combination of literature review, in-depth fieldwork at selected sites, and periodic field visits and discussions with fieldworkers and residents in communities throughout the region. The review of the literature summarizes an extensive and rich record of land-use, development, conservation, and ethnographic studies and activities in the region, from the 1890s to the present, including the major works of geographers, anthropologists, and sociologists. The field research that informs this study was part of a series of research and development projects in Machakos District to promote sustainable production and resource-management systems, with most of the fieldwork conducted between 1983 and 1992 in affiliation with the International Centre for Research in Agroforestry, or ICRAF (Nairobi), the Kenya National Environment Secretariat, the Institute for Development Studies of the University of Nairobi, and Wageningen University (the Netherlands).

In addition to participation in field trials of agro-forestry technologies and land-use planning exercises, field research included: land-use and resource mapping at the watershed and farm level; participant observation in individual and group work in agriculture, conservation, and related subsistence activities; focus group interviews, group interviews, and household interviews; key informant interviews; individual oral histories; questionnaire surveys (two sites), and participatory rural appraisal (PRA) exercises. The qualitative information from fieldwork, particularly concerning the drought and famine of 1984-1985 and current trends in migration, has substantially influenced the interpretation of census, survey, and inventory data from other sources. In addition to direct observation in regular and periodic visits to numerous sites, the discussion below also reflects the experience and analyses of technical and research staff working throughout the region, based on frequent discussion and consultation in the field and in national technical and policy forums.

The Ukambani study area

The physical setting

Ukambani is situated on a predominantly semi-arid, eastward-facing slope, which becomes progressively lower and drier to the east. It is part of Kenya's Eastern Foreland Plateau, an eroded basement complex broken by residual hill masses and occasionally overlain by Tertiary volcanics (Bernard, Campbell, and Thom 1989; Wisner 1977). Moore (1979a) describes the Machakos Hills area as hills dropping down to a series of plains, separated by steep slopes.

This part of Kenya forms an environmental gradient of decreasing altitude (from 2,100 m to 440 m), increasing temperatures, and decreasing moisture (from 1,270 to 381 mm average annual rainfall) from west to east (Ojany and Ogendo 1973; Owako 1971; Porter 1965). Elevation controls the quantity of rainfall at the regional scale, whereas topography strongly influences rainfall distribution at the local scale. Rainfall, except in the hill regions, is low and unreliable (Bernard, Campbell, and Thom 1989). The precipitation pattern is bimodal, with long rains falling between March and May and short rains from October to December (Moore 1979b; Porter 1965), as illustrated by the rainfall and cropping calendar for one site in Machakos (fig. 5.2).

The soils of Machakos and Kitui reflect the largely metamorphic parent material and the rainfall regimes that contribute to their formation (Barber, Thomas, and Moore 1981; Ojany and Ogendo 1973). In Machakos, the dominant soil groups are alfisols, ultisols, oxisols, and lithic soils (Barber, Thomas, and Moore 1981; Lerberg 1988; Porter in prep.).

These soils are all generally of low fertility, and many are highly erodible (Barber, Thomas, and Moore 1981). The ultisols and alfisols are also susceptible to sealing (capping), which increases runoff and makes the clay soils hard to plough by the end of the dry season (Barber, Thomas, and Moore 1981). A rough estimate of the agricultural quality of the region's soils indicates that less than 20 per cent of Kitui and Machakos has well-drained, deep, friable red and brown clays of good fertility; more than 60 per cent of the region has very erodible, relatively shallow, sticky, red, black, and brown clays of variable fertility, on steep slopes; 20 per cent has poorly drained, shallow, stoney soils of low fertility (Bernard, Campbell, and Thom 1989, based on Jaetzold and Schmidt 1983).

The dominant vegetation of this part of Kenya is dry bush with trees, and, in the higher areas, savanna with scattered trees (Ominde 1968). The hills were once forested, but by the beginning of the colonial period most of the "desirable" agricultural land had been cleared (Harroy 1949; Owako 1971; Silberfein 1984), leaving patches and corridors of forest along ranges, rivers, ravines, and hilltops, as well as dry forest in large expanses of grazing land. Characteristic vegetation at the higher altitudes (above 1,700 m) includes remnant evergreen forest (Podocarpus spp.) and bracken, mist forest, and evergreen thicket clumps in grassland. Elevations at 1,200-1,700 m are dominated by Combretum species, with particular plant associations correlated with topography and moisture. The most widespread vegetation type in Ukambani, and especially in Kitui, is semi-arid deciduous thicket and bushland, particularly Acacia/Commiphora associations in the 8001,200 m elevation range. In the dry areas below 900 m, Commiphora/Sanseveria thorn bush grades into semi-desert vegetation (Ojany and Ogendo 1973; Owako 1971; Porter in prep.).

The forest zone is now largely under cultivation, with shrubby secondary growth dominating non-cultivated areas. The soils characteristic of the moist Combretum areas are fairly productive for agriculture, but the dry Combretum zones have sandy soils of limited fertility. The Acacia/Commiphora zone includes perennial grasses valued for grazing (Porter in prep.), but even in these areas forest and shrubland are increasingly being converted to cropland.

Fig. 5.2 Rainfall and agricultural calendar for Mbiuni location, Machakos (Source: adapted from Darnhofer, 1985)

Fig. 5.3 Agro-ecological zones of Ukambani (Source: Jaetzold and Schmidt, 1983)

Table 5.1 Classification of agricultural land in agro-ecological zones (%)

Zones:
2, 3 Suitable for banana and coffee
4 Semi-humid to semi-and transition; suitable for maize
5 Semi-arid; suitable for livestock, millet, and sorghum
6 And; suitable for ranching

Source: Jaetzold and Schmidt (1983), Vol. 2: Natural conditions and farm management information. Part C. East Kenya (eastern and central provinces).

Biophysical agricultural potential in Ukambani is a function of soil characteristics and moisture availability, both of which are largely controlled by elevation and topography. Jaetzold and Schmidt (1983) mapped agricultural potential in Kenya using a modified version of the FAO Agroecological Zone system (fig. 5.3, table 5.1). Downing and colleagues (1987, cited by Lezberg 1988) calculated that 76 per cent of the Machakos District falls into agro-ecological zones 4 (semi-humid to semi-arid) and 5, with fully 58 per cent falling in zone 5 (suitable for livestock, sorghum, and millet). The 1980 development plan for Kitui classifies 2 per cent of the district as high potential, 37 per cent as medium potential, and 61 per cent as low potential (Republic of Kenya 1980).

Population, settlement, and land-use practices

Preliminary results from the 1989 census indicate that the current population of Machakos and Kitui districts is approximately 2 million people. The vast majority (90 per cent) of the population live in rural villages and rely on a combination of subsistence and commercial agriculture, with some wage labour (Ondiege 1992). According to a 1982/83 survey of rural households in the Machakos District, agriculture accounted for 50 per cent of income, off-farm enterprises for 17 per cent, salaries and wages for 24 per cent, and other sources for 9 per cent (Ondiege 1992).

Men's employment outside the region has a long history. For the last 50 years many Akamba men have served as soldiers and policemen, as well as wage labourers in nearby factories, plantations, and urban areas (mainly Nairobi and Mombasa, but also Machakos and Kitui towns). As sex ratios (table 5.2) and local case-studies (e.g. Mwaria 1985; O'Leary 1984; Ondiege 1992; Van Ginneken and Muller 1984) make clear, this out-migration continues to form an important part of household livelihood strategies. It is, however, increasingly common for younger people to earn wages locally for labour on other people's farms.

Table 5.2 Ukambani population: Sex ratios (adult males per 100 adult females), 1948-1979

Sources: Tiffen (1991b), Republic of Kenya (1980).

The density of population throughout much of Ukambani has exceeded the number of people that can be supported by subsistence or commercial agriculture under present technology (see Bernard, Campbell, and Thom 1989). Out-migration of men and partial remittance of wages to rural communities, from World War II up until recently, seems to have slowed the pace of land-use intensification in response to higher population densities. This pre-empted or postponed the impact of population density on technology innovation and agricultural intensification as postulated by several authors for agrarian systems elsewhere (Boserup 1965; Lagemann 1977; Ruthenberg 1980; Turner, Hanham, and Portararo 1977).

Intensification has lagged behind local population growth and, in drier areas, behind in-migration of new families from crowded upland farming communities. This has not been an obstacle for the people of the region so long as wages from outside employment could offset the deficits in production. The differential ability of households to deal with this problem has resulted in widespread movements of population and changes in land use.

Rural settlement patterns in Ukambani reflect the productive potential of the Agro-ecological zones noted earlier. The higher-potential upland areas are much more densely populated than the dry lowlands (table 5.3). In Kitui, for instance, approximately 60 per cent of the population occupies only 20 per cent of the district's land area outside of Tsavo National Park, and the population density ratio of highland to lowland divisions is approximately five to one (Republic of Kenya 1980). Using 1969 census data, for example, O'Leary (1984) found highland sublocation population densities ranging from 24 to 113 people/km² and lowland densities from 6 to 22 people/km². He also found local highland densities as high as 240 people/km².

Although district-level population figures (table 5.4) are the most accessible and the most often used, it is the movement between agro-ecological zones, and between urban and rural areas, that best reflects the dynamics of population, economy, and environment in Ukambani and neighbouring regions (Bernard 1985; Bernard and Thom 1981; Bernard, Campbell, and Thom 1989; Campbell 1990; Downing et al. 1989; Lezberg 1988; Tiffen 1991a,b). These complex patterns of movement may be obscured by district-level data, making these figures somewhat difficult to interpret. In Machakos District, for example, net increases in any given period result from a combination of natural increase, out-migration to Nairobi, Mombasa, and settlement frontiers in coastal or dry upland sites in Kitui and other districts. The district-level data are "blind', to the widespread migration from the hills to drier frontier areas within Machakos District.

Overall, population has risen steadily from the 1930s to the present (table 5.5), but rates of change have been uneven across agro-ecological zones. As table 5.5 indicates, growth rates in the high-potential areas of Machakos District declined from the 1930s to the 1960s, whereas those of the low-potential areas have remained high (Tiffen 1991b). The latter is due primarily to migration of highland Akamba into the dry agricultural frontiers of the district. O'Leary (1984) reports a similar dynamic, albeit somewhat later, for Kitui District. The imposition and lifting of barriers to movement during the colonial and immediate post-colonial periods have heavily influenced population changes through time in both districts.

Table 5.3 Population density in 1979 by agro-ecological zone (persons per km²)

Sources: Machakos - Tiffen (1991b), Republic of Kenya (1980); Kitui - Downing (1988).

Table 5.4 Population estimates for Ukambani, 1890-1989 ('000)^a

Sources: pre-1948 - based on district tax censuses and estimates reported in Owako (1971), Mwaria (1985), Tiffen (1991b); 1948-1979 - based on census figures reproduced in Republic of Kenya (1980), O'Leary (1980), Tiffen (1991b); 1989 - preliminary census figures for Machakos, reported by Tiffen (1991b), Ondiege (1993).
a. Formal census figures are not available before 1948, and district and tax figures are notoriously inaccurate. In addition, the boundaries of administrative units have changed, making raw census figures non-comparable through time. The figures given here are approximate and should be taken as indicators of relative magnitude and trend directions.
b. Based on 190211910 reports on estimates of 50% mortality during famine and on conflicting reports on population prior to famine.

Table 5.5 Machakos population by agro-ecological zone, 1932-1979

Source: Tiffen (1991b).

Land-use change

As urban and civil service opportunities contract, or fail to keep pace with the growing demand from Ukambani and other regions, many men have returned home to farm and young people are increasingly choosing not to leave. This has spurred a new cycle of agricultural intensification and experimentation in many communities since the beginning of the 1990s. The current process of land-use intensification represents a delayed response to higher population density overall and to progressive displacement of population into the drier portions of Ukambani. The changes in land use and settlement also reflect a changing pattern of land tenure, in both the character and the distribution of land rights.

Landholdings range from 0 to 1000's of hectares (ha), with most households in agro-ecological zone 4 owning 2-10 ha and in zone 5 owning 2-15 ha (Hoekstra 1984; Ondiege 1992; Rocheleau, Baumer, and Depommier 1985). As land is subdivided and allocated or sold to the rising generation, however, farm sizes of 0.5-1 ha have become commonplace in zone 4. Among all holdings in Machakos District (all zones), 30 per cent are less than 0.9 ha in size; the figure for Kitui is 17 per cent (Ondiege 1992). Increasing numbers of people in zone 4 have been rendered landless, or forced to migrate to urban areas (mostly men), to plantations (mostly women), or to zone 5 frontier areas (whole families and clusters of brothers, sisters, and friends with families). In Machakos, as migrants from zone 4 and resident young people subdivide the available land in zone 5, the landholding size there is also shrinking rapidly (Hoekstra 1984; Porter in prep.; Rocheleau 1985, 1992; Rocheleau, Baumer, and Depommier 1985; Tiffen 1991a,b). New settlers to these areas often purchase plots of 5-10 ha.

In Kitui, westward migration from the crowded central highlands toward Yatta Plateau had virtually ceased by the early 1980s, resulting in increased fragmentation of highland holdings to non-viable dimensions (O'Leary 1984). Meanwhile, manipulation of land markets and state development schemes allowed the wealthy to accumulate sizeable holdings in both highland and lowland areas of Kitui (Mutiso 1975). By the late 1980s, an estimated 6 per cent of Kitui households were landless (Ondiege 1992). In the dry areas, in which shifting cultivation and "bush fallow" systems have been widely practiced, the current "land rush" (Weekly Review 1991a,b,c,d) is rapidly filling in the dry forest, "fallow," and grazing lands between cropped fields in established farming communities.

Most households (with an average of eight persons) keep both cattle and goats, with an average of two cattle and eight goats or sheep in Machakos and somewhat higher numbers in Kitui (Ackello-Ogutu 1991). The most common food crops are maize, beans, cowpeas, pigeon peas, pumpkins, sweet potatoes, green gram, and bananas. Farmers intercrop maize, beans, bananas, potatoes, sweet potatoes, pumpkins, and sometimes coffee in the wet uplands of Ukambani. Many upland coffee farmers also grow other tree crops, including macadamia nuts, mango, papaya, timber, and fuelwood. Cabbages, tomatoes, onions, red peppers, and greens are usually limited to river flood plains or poorly drained valley sites. In the drier parts of the region most farmers grow maize, beans (on moister sites), cowpeas, pigeon peas, and sometimes green gram and cotton. Sorghum and millet, once the staple grains, are found in small patches in croplands, but have been largely replaced by maize. Sweet potatoes, pumpkins, and bananas are fitted into the wetter sites in the field, along the base of terrace walls, in deep pits (1 m³) with fruit trees, on termite mounds, or in gardens near the home. Increasingly, farmers in zone 4 are also intercropping papaya, citrus, and some fodder or timber trees with their field crops.

The typical crop mix raised by a farm household still varies substantially between eco-zones but increasingly also varies within eco-zones between households and between more localized landscape niches determined by topographic location, soil type, soil moisture, and proximity to water points and to forest. Whereas single households (usually extended families sharing production and consumption) once maintained a number of fields, across eco-zones, most farm households are now reduced to nuclear families or smaller extended family units cultivating a single plot or a cluster of similar plots in one eco-zone. Moreover, most households in the past relied on a regular supplement of food supply from wild and semi-domesticated plants in forests, hedgerows, rangelands, and fallows.

The resulting paradox is that, although new food and commercial crops may have increased and the total number of crops in individual fields may be greater, the total number of crops raised and the variety of plants used by any given household may be fewer than 20 years ago. The exceptions are small home gardens and the orchard-like mixed-cropping systems of some largeholders, based on tree crops such as citrus, papaya, banana, and other fruits. Even there, the loss of many wild and semi-domesticated plants has resulted in a net loss of diversity in locally available foods. For the wealthiest this is compensated by purchased foods, whereas for the poorest it represents a deterioration in nutritional quality, seasonal distribution, and reliability of food supply (Rocheleau et al. 1985; Van Ginneken and Muller 1984).

Environmental hazards and environmental degradation

For most of Machakos and Kitui, the main limiting factors for settlement and agriculture are the lack of rainfall and of reliable sources of surface water (Owako 1971). The latter has been further exacerbated by disruption of streamflow due to deforestation. Most streams are intermittent and deeply incised (Moore 1979a). In some areas, ticks and tsetse here limited livestock development into the 1970s (Owako 1971). Since these disease vectors are vegetation dependent, their presence was once marked by clear boundaries, well known to the Akamba people (Porter 1965). There is less certainty under present conditions in complex, finely divided mosaics of bush, cropland, and pasture, and tsetse flies have been reported in settled areas along the Athi River and the Yatta Plateau (J. Kyengo, L. Kyongo, and M. Musyoki personal communication). Crop environmental limits have always been less clear (Porter 1965), tempting government and international agencies to push agricultural settlement into dry or hilly areas not capable of supporting intensive maize cultivation under existing levels of technology (Bernard, Campbell, and Thom 1989).

One underestimated and underreported constraint on crop mix and management is proximity to forest, particularly in dry forest frontier plots. Large and small herbivores, from rhinoceros and elephant (in the 1950s and 1960s), to monkeys, baboons, wild hogs, squirrels, and antelope (at present), cause serious but selective damage to field crops. Herbivory by mammals causes farmers to change the composition of intercropping systems as well as their management practice, not to mention their own sleep habits. Many farmers keep all-night vigils in their fields just prior to harvest to protect grain and roots from marauding nocturnal animals (field interviews, Machakos and Kitui 1991; Lelo 1994).

Land degradation by cropping and overgrazing has been a recurring theme throughout the last 70 years of colonial and later national agricultural and resource-management programmes. In this region, the high susceptibility of cropland to erosion derives from a combination of factors: concentrated settlement in fertile and well-watered hilly terrain; the tendency of the soils to "cap"; and the fact that 70 per cent of the most erosive rainstorms occur in the first month of the rainy season, before crops can establish an effective cover (Barber, Thomas, and Moore 1981; Moore 1979a,b). Cattle, goats, and sheep also have pronounced effects on those Ukambani soils that have a propensity to form a pavement-like surface when denuded by overgrazing and physically compacted by trampling. The resulting land degradation, in turn, reduces future crop and livestock production.

Although the climate, soil, and topography of Ukambani make the region susceptible to erosion, compaction, and denudation, crop and livestock management practices can exacerbate, prevent, or even reverse land degradation. Figure 5.4 illustrates the complex interaction of causal relations between agricultural production and environmental degradation at the farm level as derived from surveys in Mbiuni location, Machakos (Raintree 1984; Rocheleau 1985; Vonk 1983b). Several points of technical intervention could reverse or at least ameliorate land-degradation and production problems.

In reality, both regional and local variation in physical characteristics and cultural practices determines the potential for crop and livestock production and the condition of land and water resources in Ukambani. The state has tended to work primarily from regional-level differentiation of agricultural potential, whereas farmers and herders tended to focus more on local-level variations. Rural people in the region have often been thwarted by settlement, tenure, and agricultural development policies that force them into single "consolidated" holdings. There, they are expected to pursue a single land use, with household heads as single points of ownership and control. Land allocation has also tended to treat all local land as equivalent in inherent characteristics, current condition, productive potential, and vulnerability to damage. Likewise, many agricultural production and conservation programmes have promoted single-technology packages to achieve "sustainable production."

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