Knowledge for Development

Feature articles

Mapping drought patterns and impacts: A global perspective

This study examines the global patterns and impacts of droughts through the mapping of several drought-related characteristics – either at a country level or at regular grid scales. Characteristics cover various aspects of droughts – from global distribution of meteorological and hydrological drought risks to social vulnerability and indices related to water infrastructure. The maps are produced by integrating a number of publicly available global datasets. The subsequent discussion of maps allows a number of policy-relevant messages to be extracted. It appears that arid and semi-arid areas also tend to have a higher probability of drought occurrence. The report points out that in drought years, the highest per capita loss of river flow occurs in areas that do not normally experience climate-driven water scarcity. It also illustrates that the African continent is lagging behind the rest of the world on many indicators related to drought preparedness and that agricultural economies, overall, are much more vulnerable to adverse societal impacts of meteorological droughts. Regions with an unreliable and vulnerable nature of river discharge, and having the largest drought deficits and durations are highlighted, pointing to the danger of focusing on drought mitigation measures on river flows alone. The ability of various countries to satisfy their water needs during drought conditions is examined using storage-related indices.Authors: N. Eriyagama, V. Shmaktin & N. Gamage, International Water Management Institute research report 133, 2009


Introducing cactus-based agro-forestry practices to the drylands

The drylands of Ethiopia have poor vegetation cover and have a high evapo-transpiration that exceeds precipitation. The identification of suitable plant species that can thrive and produce yields and contribute to farming practices add to resilience. One such plant species is the cactus pear, Opuntia ficus-indica (L.) Mill.This plant has many possible uses and benefits, from fresh fruits and stem segments as vegetables or livestock feed over jam and pigments to sugar or ethanol extraction. One likely option for cultivation would be the introduction of cactus into farmlands as hedges or intercrops with an additional advantage in mitigating the impacts of climate change. Mekelle research centre conducted an observation on an orchard of 11 cactus pear cultivars intercropped with beans that yielded a significantly higher biomass in addition to increasing the vegetation cover. Cactus-based agro forestry practice can therefore be considered as an adaptation option to climate change in the drylands.The author of this article, Tesfay Belay, works for the Tigray Agricultural Research Institute, P O Box 492, Mekelle, Ethiopia.This article is part of the Knowledge for Development dossier on Dryland Agriculture.


New dossier: dryland agriculture

The United Nations declared 2006 as the International Year of Deserts and Desertification. The UN General Assembly was deeply concerned about the exacerbation of desertification, particularly in Africa. In recognition of this challenge facing the African continent, and given that several of the affected countries comprise one of the key constituents of the ACP Group of States, CTA commissioned this new dossier on drylands. The information presented therein will also complement the strategic partnership that CTA embarked on at the beginning of January 2007 with international, regional and national partners to implement an EU funded international cooperation project (INCO) project under the 6th EDF programme which aims to identify success stories on Agricultural Innovations in Dryland Africa (AIDA) to determine the drivers of success. This dossier provides two lead articles; one by Dr Wellington Ekaya of the University of Nairobi, Kenya and the other by Dr Mary Tiffen of the UK. Both authors highlight the need for researchers to be more innovative in their approach to conducting research in dryland communities by building partnerships with the indigenous farming communities and drawing on their knowledge to ensure successful interventions that can benefit society. The web links guide you to a range of resources within the ACP, EU and internationally from which lessons can be drawn to support further research and policy interventions. Read this new dossier .


Changing farming strategies with a closing farm frontier and urbanisation in dryland Africa- Are Researchers Aware?

In many parts of dryland Africa most suitable land is already farmed due to the expansion of rural populations. This means that land has become a scarce resource. Those who want to enlarge a farm do so by buying or renting in land, or in some extreme cases, if sufficiently powerful, grabbing or confiscating it. In such areas fallowing land is no longer possible. To maintain fertility, farmers have to turn to other strategies like manuring or using chemical fertilisers. Besides, there is also little land available for communal grazing, except perhaps on roadside verges. Crop residues and the dry season weed growth have become the valued personal property of the cultivator. This is now the position in all areas where the population has risen above 40 persons per km2. The way the land has filled can be illustrated by the changes in the former Kano Province of Nigeria between 1960 and 1991 (Figure 1). Here, farmers seeking new land must move out of their home state, for there is no longer any free land either in the north, near the Niger border, or in what was tsetse infested bush in the south (Tiffen 2001). This can also be seen in Senegal (Ba et al. 2000) . In some west African countries there is still some cultivable land available, either on the desert margins, where farming becomes very risky, (for example in Niger), or, in what is termed the Middle Belt in West Africa, where new settlers are cutting bush and forcing the tsetse fly to retreat. In much of Kenya and a great part of Uganda, land is scarce, but there is rather more uncultivated, and unclaimed, bush in Zambia and Zimbabwe.


Strategies for Developing Dryland Agriculture: Role of Knowledge

In Africa, the drylands, excluding the deserts, comprise about 43% of the continent’s surface area. These areas are home to about 40% of the continent’s population, i.e. about 268 million people. Cultivable dryland is scarce, and farm holdings are getting smaller. Grazing resources are under increasing pressure and soils are being severely affected by salinity due to intensive irrigation. The list of challenges is long. From a global perspective, the following key reasons justify the concern for drylands: People living in drylands constitute a large fraction of the world’s poorest. According to United Nations Development Fund (UNDP’s) Human Development Index, over 50% of the world’s most disadvantaged countries are in dryland Africa. Achievement of the Millennium Development Goals (MDG’s) becomes highly unlikely, unless poverty reduction is significantly realized in drylands. They are a major repository for the world’s biodiversity and therefore constitute a major focus point for the UN Convention on Biodiversity. Because of their vastness, drylands have the potential to be a significant sink for carbon. Ecosystem characteristics affecting the magnitude of carbon stores include rainfall, temperature, CO2 concentration, productivity, species mixes, vegetation physiognomy, soil type and rooting depth of grasses. Drylands bare increased risks and large-scale land use changes due to global climate changes. iv. Drylands make a significant contribution to the Gross Domestic Product (GDP), particularly in terms of livestock products and food grains, but also tourism and related activities.