Mapping Grazing-Induced Degradation in a Semi-Arid Environment: A Rapid and Cost Effective Approach for Assessment and Monitoring

Improved techniques for measuring and monitoring the state of biodiversity are required for reporting on national obligations to international and regional conservation institutions. Measuring the extent of grazing-related degradation in semi-arid ecosystems has proved difficult. Here we present an accurate and cost-effective method for doing this, and apply it in a South African semi-arid region that forms part of a globally significant biodiversity hotspot. We grouped structurally and functionally similar vegetation units, which were expert-mapped at the 1:50,000 scale, into four habitat types, and developed habitat-specific degradation models. We quantified degradation into three categories, using differences between dry and wet season values of the Normalized Difference Vegetation Index (NDVI) for the three succulent karoo habitats, and the difference between maximum and mean NDVI values for the subtropical thicket habitat. Field evaluation revealed an accuracy of 86%. Overall, degradation was high: 24% of the study area was modeled as severely degraded, and only 9% as intact. Levels of degradation were highest for bottomland habitats that were most exposed to grazing impacts. In sharp contrast to our methods, a widely used, broad-scale and snapshot assessment of land cover in South Africa was only 33% accurate, and it considerably underestimated the extent of severely degraded habitat in the study area. While our approach requires a multidisciplinary team, and in particular expert knowledge on the characteristics and spatial delimitation of vegetation types, it is repeatable, rapid, and relatively inexpensive. Consequently, it holds great promise for monitoring and evaluation programs in semi-arid ecosystems, in Africa, and beyond.     

Property rights and governance of Africa's rangelands: A policy overview

Recent efforts at securing property rights in dryland Africa have generally involved several interrelated processes such as legal and policy reforms that recognize and strengthen customary rights or the seasonal rights of pastoralists, and the decentralization of land allocation and administration to lower governance levels. These solutions are in turn beset by new problems, key among them are establishing norms for local participation in decision making, preventing manipulation and capture by elites, lack of accountability of local level institutions and authorities, and the onset of a new generation of resource user conflicts. Increasing avenues through which dialogue and communication can occur among policy actors (including local communities) in order to mobilize multiple experiences, information, and to manage power relationships — a collaborative approach to policy governance — is one way of approaching the complexity paradox. This is anticipated to provide opportunity for learning, innovation and adaptability.     

Human Migration,Protected Areas,and Conservation Outreach in Tanzania

A recent discussion debates the extent of human in‐migration around protected areas (PAs) in the tropics. One proposed argument is that rural migrants move to bordering areas to access conservation outreach benefits. A counter proposal maintains that PAs have largely negative effects on local populations and that outreach initiatives even if successful present insufficient benefits to drive in‐migration. Using data from Tanzania, we examined merits of statistical tests and spatial methods used previously to evaluate migration near PAs and applied hierarchical modeling with appropriate controls for demographic and geographic factors to advance the debate. Areas bordering national parks in Tanzania did not have elevated rates of in‐migration. Low baseline population density and high vegetation productivity with low interannual variation rather than conservation outreach explained observed migration patterns. More generally we argue that to produce results of conservation policy significance, analyses must be conducted at appropriate scales, and we caution against use of demographic data without appropriate controls when drawing conclusions about migration dynamics. La Migración Humana, Áreas Protegidas y el Alcance de la Conservación en Tanzania     

The rains are disappointing us: dynamic vulnerability and adaptation to multiple stressors in the Afram Plains, Ghana

This paper builds on work on the dynamics of vulnerability and multiple stressors through a case study in the Afram Plains of the Eastern region in Ghana. A vulnerability framework is applied in the community of Mimkyemfre to identify and explain the multiple underlying political, socioeconomic and environmental forces that influence the ways in which people are exposed and sensitive to climate, and their capacities to adapt to changing conditions. The results of the study indicate that the community experiences a range of biophysical and socioeconomic conditions that contribute to its vulnerability. Vulnerability was found to change over time and in some cases was cyclical, in that certain actions taken for the purposes of adaptation were found to exacerbate existing vulnerabilities. Processes of vulnerability were also found to occur at several scales and were experienced unevenly at the community level. The findings of this assessment have important implications for the design and implementation of successful adaptation initiatives, both in Africa and elsewhere. In particular, they demonstrate the need to understand the social, economic and institutional challenges to development as a basis for any contemplation of adaptation to climate change.     

Effects of Local Disturbance of Tropical Forests on Frugivores and Seed Removal of a Small-Seeded Afrotropical Tree

Abstract:  Small-scale, local disturbance of tropical forests, for example from selective logging, is widespread, but its effects on biodiversity and ecosystem function have rarely been studied. In 3 East African tropical rainforests, we investigated the effect of different levels of local forest disturbance on the frugivore community and on tree visitation and fruit removal rates of the small-seeded tree Celtis durandii. We quantified birds and primates in little and heavily disturbed sites, distinguishing between forest specialists, forest generalists, and forest visitors. We quantified frugivorous tree visitors and seed removal rates of C. durandii trees in the same sites. Forest disturbance reduced the species richness and density of the frugivore community and of forest specialists. Frugivorous species and individuals visiting the study trees were reduced significantly, which led to a marginally significant decline in fruit removal by all frugivores and a significant reduction in removal by forest specialists. Reduction in fruit removal by forest specialists was not compensated for by increases in removal by forest generalists or visitors. Results did not differ among the 3 rainforests, which suggests they were consistent at a regional scale. So local forest disturbance led to a loss of frugivores and their seed removal services. This suggests that large-seeded tree species and trees with small fruits are losing seed dispersers. Thus, local forest disturbance appears to have a more general negative impact on frugivores and their seed dispersal services than anticipated previously.     

Building the Capacity of Grassroots Conservation Organizations to Conduct Participatory Evaluation

Stakeholder participation has become a key factor in the success of grassroots conservation and natural resource management programs. Yet the majority of program evaluations are conducted by external consultants for the purposes of accountability, rather than program improvement. Too often, systematic evaluations of conservation programs are not conducted at all. The objective of this study was to build the capacity of a grassroots conservation organization to conduct participatory evaluation, involving project stakeholders in the design, implementation, and use of evaluation. The study applied a conceptual model for participatory evaluation to the Wildlife Clubs of Kenya (WCK), the largest grassroots conservation program for youth in Africa, involving more than one million youth since 1968. Seven trainings in participatory evaluation were conducted with WCK staff, teachers, and community members. The 120 participants, representing nine WCK regions with 800 clubs, showed a significant increase in attitudes and knowledge regarding evaluation, as reflected by mean test scores before and after training. To institutionalize evaluation at WCK, existing organizational practices were assessed and used as a foundation for developing an evaluation system. Based on club competitions, a new evaluation initiative was launched called the WCK Incentive Program. Participants in all seven workshops identified indicators and sources of evidence for this evaluation system, which now serves as a basis for rewarding outstanding performance in WCK. This study revealed the importance of incentives for evaluation, the need to build on existing structures to promote organizational learning, and the necessity for the conservation community to commit resources to capacity building in participatory evaluation.     

The Exploitation and Environmental Legacy of Amphibole Asbestos : A Late 20th Century Overview

The risk to human health associated with the inhalation of amphibole asbestos has become devastatingly ap- parent this century. The most commonly utilised asbestiform amphiboles, crocidolite (blue asbestos) and amosite (brown asbestos), are implicated in a variety of diseases related to cell damage within the respiratory tract and adjacent areas. Blue and brown asbestos fibres have a morphology and mineralogy which makes them more biopersistent and biochemically reactive than chrysotile (white asbestos). The long-term pres- ence of such fibres within and around the lungs can result in fibrous scarring, lung cancer, and is the major cause of the once extremely rare tumour known as diffuse malignant mesothelioma. Therefore, despite the fact that asbestiformamphiboles comprise approximately 5%of industrially utilised asbestos (the rest being chrysotile), they have been disproportionately pathogenic. Almost all amphibole asbestos sold on the world market was mined from Palaeoproterozoic ironstones in either the northern Cape Province (blue) or Trans- vaal (brown and blue) areas in South Africa. Production peaked from 1966–1978 when around 2 million tons of crocidolite and1million tons of amosite were produced and exported to be used mainly in asbestos-based cement products and many types of building materials. Crocidolite mixed with chrysotile was commonly used in pressure pipes and gaskets, whereas amosite mixed with chrysotile was especially suitable for gut- ters, roofing, and insulation boards. Amid- to late 20th century amphibole asbestos-related cancer epidemic has consequently struck not only mining and milling communities in producer countries, but many groups of workers (and their relatives and neighbours) exposed to amphibole asbestos-bearing materials in importer countries. Although belated closure and reparation of the mines and imposition of threshold safety limits in the workplace will eventually stem this epidemic the death toll has not yet peaked. Given the long latency period (decades) typical of mesothelioma and bronchogenic carcinoma and the fact that amphibole asbes- tos-bearing materials are still present in some buildings, asbestos-related cancer will inevitably continue to be a major cause of death in many countries worldwide well into the next century.     

Tourism effects on the environment and economic sustainability of sub-Saharan Africa

This paper integrates tourism, economic growth, and environmental issues in a multivariate format. Unlike recent research on this topic, a panel data of selected sample nations of sub-Saharan Africa is adopted by using cointegration and panel regression models. The current research discovers both long-run equilibrium and short-run dynamics between economic growth, tourism, energy use, and carbon emissions in sub-Saharan Africa. Furthermore, tourism and energy use show a highly significant direct impact on economic growth. In addition, tourism, energy use, and economic growth yield a highly significant positive effect on carbon emissions. Dissecting the region into oil producers and non-oil producers further suggests that the economic growth of sub-Saharan Africa has been accomplished by strong growth in tourism and energy use. However, there is highly significant evidence that in oil producing countries, CO₂ emissions are directly affected by energy use and economic growth and not by tourism. For non-oil producing countries, tourism and energy use but not economic growth incur a highly significant positive impact on carbon emissions.     

Climate change and human security in Africa

Climate change poses a major threat to human security and poverty in Africa. In Africa, where livelihoods are mainly based on climate-dependent resources and environment, the effect of climate change will be disproportionate and severe. Moreover, Africa's capacity to adapt to and cope with the adverse effects of climate variability is generally weak. This article discusses how climate change affects human security in Africa. It also assesses the policy options available to policymakers in terms of mitigation and adaptation to climate change to reduce vulnerability and human insecurity in Africa.