Understanding the role of local management in vegetation recovery around pastoral settlements in northern Kenya.

The recent greening of the Sahel region and increase in vegetation cover around pastoral settlements previously described as "man-made deserts", have raised important questions on the permanency of land degradation associated with the over-exploitation of woody plants. Evidence presented is mostly on increased wetness, while management by local communities has received limited attention. This study evaluated changes in woody vegetation cover around the settlements of Kargi and Korr in northern Kenya, using satellite imagery (1986/2000), ecological ground surveys and interviews with local elders, in order to understand long-term changes in vegetation cover and the role of local community in vegetation dynamics. At both settlements, there were increments in vegetation cover and reduction in the extent of bare ground between 1986 and 2000. At Kargi settlement, there were more tree seedlings in the centre of settlement than further away. Mature tree class was more abundant in the centre of Korr than outside the settlement. The success of the regeneration and recovery of tree cover was attributed to the actions of vegetation management initiative including stringent measures by the local Environmental Management Committees. This study provides good evidence that local partnership is important for sustainable management of resources especially in rural areas where the effectiveness of government initiative is lacking.

Cattle herd vulnerability to rainfall variability: responses to two management scenarios in southern Ethiopia.

We examine how the system of grazing management of cattle in savanna rangelands affects the herd response to drought. We have used long-term time series data to evaluate the effects of management on drought-induced cattle mortality using traditional livestock management practices. There was no control of stocking densities, as compared to a government ranch where stocking densities would be adjusted in accordance with available pasture. We tested the responses under two scenarios. Scenario 1: Response of cattle herds to inter-annual rainfall variability (IRV) under a regulated grazing management system; this provides more reliable predictions of cattle population and performance in terms of herd mortality and calving rates than does the communal land use system. Scenario 2: Regardless of the management system, similar trends in cattle populations will be observed in response to IRV. The results of the study showed that fluctuations in cattle numbers, herd mortality and calving rates were highly correlated with IRV, with stronger linear impacts in accordance with scenario 2. In both management systems, cattle herd sizes and calving rates declined during periods of drought, followed by slow recovery. Cattle populations in Borana rangelands in southern Ethiopia did not recover for a period of two decades. We conclude that a management system based on control of stocking densities did not improve herd survival, as compared with traditional drought management strategies. This contradicts common expectations. Increased drought frequencies aggravated cattle mortality and lowered calving rates. The implication of the findings is that regardless of adjusted stocking density, livestock populations in the arid savanna ecosystems of southern Ethiopia remain at risk from climate change.

Human stewardship or ruining cultural landscapes of the ancient Tula wells, southern Ethiopia.

This article uses the concepts of "human stewardship" and "ruined landscape" as a theoretical framework for analysing the community's perception of landscape change in the ancient tula well system of Borana in southern Ethiopia. The ancient tula well system, the main permanent water source, has been in operation for more than five centuries and it closely links human activity and the environment. The welfare of the tula well system and the performance of the Borana pastoral system are directly related. Borana management of the tula wells uses concepts such as laaf aadaa seeraa and laaf bade to differentiate between 'land managed by customary laws' (hereafter human stewardship) and 'lost' or 'ruined' land (laaf bade). The cultural landscapes of the ancient wells have undergone changes from ecosystems featuring 'human stewardship' (before the 1960s), that is, laaf aadaa seeraa to 'ruined landscapes' (after the 1960s), that is, laaf bade. Our interest is in understanding how the Borana perceive the impact of land use changes from these two conceptual perspectives. In group discussions, key informant interviews and household surveys across five of the nine well clusters, we found that the society described the changed tula cultural landscape in terms of drivers of well dynamics (i.e. use and disuse), break up of land use zonations, patterns of human settlement (traditional versus peri-urban), expansion of crop cultivation, and changes in environmental quality. Using the two concepts, we analysed linkages between changing patterns of land use that transformed the system from laaf aadaa seeraa, which ensured human stewardship, to laaf bade, which resulted in ruined landscapes. From these we analysed environmental narratives that showed how the society differentiated the past human stewardship that ensured sustainable landscape management from the present ruining of tula well cultural landscapes.

Community participatory landscape classification and biodiversity assessment and monitoring of grazing lands in northern Kenya.

In this study, we asked the Ariaal herders of northern Kenya to answer "why, what and how" they classified landscape, and assessed and monitored the biodiversity of 10 km(2) of grazing land. To answer the "why question" the herders classified grazing resources into 39 landscape patches grouped into six landscape types and classified soil as 'warm', 'intermediate' or 'cold' for the purpose of land use. For the "what question" the herders used soil conditions and vegetation characteristics to assess biodiversity. Plant species were described as 'increasers', 'decreasers' or 'stable'. The decreaser species were mostly grasses and forbs preferred for cattle and sheep grazing and the increasers were mostly woody species preferred by goats. The herders evaluated biodiversity in terms of key forage species and used absence or presence of the preferred species from individual landscapes for monitoring change in biodiversity. For the "how question" the herders used anthropogenic indicators concerned with livestock management for assessing landscape potential and suitability for grazing. The anthropogenic indicators were related to soils and biodiversity. The herders used plant species grazing preferences to determine the links between livestock production and biodiversity. By addressing these three questions, the study shows the value of incorporating the indigenous knowledge of herders into classification of landscape and assessment and monitoring of biodiversity in the grazing lands. We conclude that herder knowledge of biodiversity is related to the use as opposed to exclusive conservation practices. This type of knowledge is extremely valuable to conservation agencies for establishing a baseline for monitoring changes in biodiversity in the future.

Effects of anthropogenic fire history on savanna vegetation in northeastern Namibia.

Anthropogenic fires in Africa are an ancient form of environmental disturbance, which probably have shaped the savanna vegetation more than any other human induced disturbance. Despite anthropogenic fires having played a significant role in savanna management by herders, previous ecological research did not incorporate the traditional knowledge of anthropogenic fire history. This paper integrates ecological data and anthropogenic fire history, as reconstructed by herders, to assess landscape and regional level vegetation change in northeastern Namibia. We investigated effects of fire frequency (i.e. <5, 5-10 and >10 years) to understand changes in vegetation cover, life form species richness and savanna conditions (defined as a ratio of shrub cover to herbaceous cover). Additionally, we analysed trends in the vegetation variables between different fire histories at the landscape and regional scales. Shrub cover was negatively correlated to herbaceous cover and herbaceous species richness. The findings showed that bush cover homogenisation at landscape and regional scales may suggest that the problem of bush encroachment was widespread. Frequent fires reduced shrub cover temporarily and promoted herbaceous cover. The effects on tree cover were less dramatic. The response to fire history was scale-independent for shrub, herbaceous and tree cover, but scale-dependent for the richness of grass and tree life forms. Fire history, and not grazing pressure, improved savanna conditions. The findings emphasise the need to assess effects of anthropogenic fires on vegetation change before introducing new fire management policies in savanna ecosystems of northeastern Namibia.