In-migrants and exclusion in east African rangelands: access, tenure and conflict

East African rangelands have a long history of population mobility linked to competition over key resources, negotiated access, and outright conflict. Both in the literature and in local discourse, in-migration is presented as leading to increased competition, driving poverty and social exclusion on the one hand, and conflict and violence on the other. Current analyses in developing countries identify economic differences, ethnic fault lines, ecological stresses and a breakdown in state provision of human and constitutional rights as factors in driving conflict. The present paper explores this interaction of in-migration and conflict with respect to Kenyan and Tanzanian pastoralist areas and populations. Using quantitative and qualitative methods, patterns of resource access and control in Kenya and Tanzania Maasailand are explored in terms of the ways land and livestock are associated with migration status, ethnicity and wealth or political class. Contrasts and similarities between the two national contexts are used to develop a better understanding of the ways these factors operate under different systems of tenure and access. The conclusion briefly considers implications of these patterns, their potential for exacerbating poverty, and policies for minimising social exclusion and conflict in East African rangelands. / Abstract in French: Les prairies d'Afrique orientale connaissent depuis longtemps une mobilité des populations, liée aux problèmes de concurrence pour les ressources clés, d'accès négocié et de conflits pures et simples. Dans la littérature comme dans le discours local, l'immigration interne est présentée comme cause de concurrence accrue, motrice de pauvreté et d'exclusion sociale d'une part, et de conflit et de violence d'autre part. Des analyses menées actuellement dans les pays en développement identifient comme facteurs moteurs de conflit des écarts économiques, des failles ethniques, des tensions écologiques et une détérioration des droits humains et constitutionnels. Cet article examine l'interaction entre immigration interne et conflit au sein des régions et populations pastorales du Kenya et de la Tanzanie. Il utilise des méthodes quantitatives et qualitatives pour étudier les modèles d'accès et de contrôle des ressources dans le pays masaï du Kenya et de la Tanzanie en termes d'association des terres et du bétail au statut d'immigration, à l'ethnicité et à la catégorie de richesse ou politique. Les contrastes et similarités entre les deux contextes nationaux servent à mieux comprendre le mode de fonctionnement de ces facteurs dans des régimes fonciers et systèmes d'accès différents. La conclusion examine brièvement les implications de ces modèles, leur capacitéà exacerber la pauvreté et les politiques de minimisation de l'exclusion sociale et des conflits dans les prairies d'Afrique orientale

The role of agroforestry in restoring Brazil's Atlantic Forest: Opportunities and challenges for smallholder farmers

Restoring the degraded Atlantic Forest is one of the biggest conservation challenges in Brazil. In a biome with high human presence, understanding the potential for restoration approaches, such as agroforestry, to provide benefits to smallholder farmers and biodiversity is essential in developing equitable restoration strategies. Smallholder or family farmers are essential to national food security, producing most fruit and vegetables consumed in Brazil. Their farms can also provide ecological stepping stones for biodiversity. To better understand their role in Atlantic Forest restoration, this study explores the use of agroforestry by smallholder farmers from the Movimento Sem Terra (MST), the Rural Landless Workers' Movement, in Pontal do Paranapanema. We use quantitative and qualitative data to assess farmer perceptions of the measures which support agroforestry farming, barriers to implementation and its impact on indicators of wellbeing. We find agroforestry farmers report significant benefits in 8 of 18 tested indicators. Attitudes to agroforestry are varied, but common themes emerge including the high value of tree cover for shade and cooling effects, and the difficulties in selling agroforestry products. Our results show lack of policy support and initial investment needs are the biggest constraints to agroforestry, but opportunity cost is not considered a large barrier. Tailored policies and financial measures are needed to integrate thousands of smallholder farmers into the Atlantic Forest restoration agenda, helping to reach biome restoration targets while supporting rural livelihoods and national food security. Further research is required into links between additional socio-economic and biogeographical variables and agroforestry uptake in the region

An optical study of interdiffusion in ZnSe/ZnCdSe

Copyright 1996 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. This article appeared in Applied Physics Letters 69, 1579 (1996) and may be found at

The activation energy for GaAs/AlGaAs interdiffusion

Copyright 1997 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. This article appeared in Journal of Applied Physics 82, 4842 (1997) and may be found at

Rural protein insufficiency in a wildlife-depleted west African farm-forest landscape

Introduction: Wildlife is an important source of protein for many people in developing countries. Yet wildlife depletion due to overexploitation is common throughout the humid tropics and its effect on protein security, especially for vulnerable households, is poorly understood. This is problematic for both sustainable rural development and conservation management. Methods: This study investigates a key dimension of protein security in a cash-crop farming community living in a wildlife-depleted farm-forest landscape in SW Ghana, a region where protein–energy malnutrition persists. Specifically, we monitored protein sufficiency, defined as whether consumption met daily requirements, as benchmarked by recommended daily allowance (RDA). We focus on whether more vulnerable households were less likely to be able to meet their protein needs, where vulnerability was defined by wealth, agricultural season and gender of the household head. Our central hypothesis was: (a) vulnerable households are less likely to consume sufficient protein. In the context that most plant proteins were home-produced, so likely relatively accessible to all households, while most animal proteins were purchased, so likely less accessible to vulnerable households, we tested two further hypotheses: (b) vulnerable households depend more on plant protein to cover their protein needs; and (c) vulnerable households are less likely to earn sufficient cash income to meet their protein needs through purchased animal sources. Results: Between 14% and 60% of households (depending on plant protein content assumptions) consumed less than the RDA for protein, but neither protein consumption nor protein sufficiency co-varied with household vulnerability. Fish, livestock and food crops comprised 85% of total protein intake and strongly affected protein sufficiency. However, bushmeat remained an important protein source (15% of total consumption), especially during the post-harvest season when it averaged 26% of total protein consumption. Across the year, 89% of households experienced at least one occasion when they had insufficient income to cover their protein needs through animal protein purchases. The extent of this income shortage was highest during the lean season and among poorer households. Conclusions: These findings indicate that despite wildlife depletion, bushmeat continues to make a substantial contribution to protein consumption, especially during the agricultural lean season. Income shortages among farmers limit their ability to purchase bushmeat or its substitutes, suggesting that wildlife depletion may cause malnutrition

Interdiffusion: A probe of vacancy diffusion in III-V materials

Copyright 1997 by the American Physical Society. Article is available at