Features of drylands
Drylands are areas with limited water resources. Rainfall is scarce, unreliable and concentrated during a short rainy season with the remaining period tending to be relatively or absolutely dry. High temperatures during the rainy season cause much of the rainfall to be lost through evaporation, and the intensity of storms ensures that much of it runs off in floods. Aridity and variability are two dominant characteristics of dryland climate and several classifications based on aridity have been developed. It is apparent that the FAO and UNEP approaches and classifications produce divergent assessments of the range and extent of drylands throughout the world (Table 1).
Table 1: Alternative classifications of aridity for the for the African drylands
(a) LGP: The duration when both water and temperature permit crop growth (FAO, 1984)
(b) Aridity Index: Precipitation over Potential Evapotranspiration (UNEP, 1992)
Dryland climatic conditions strongly influence the natural and socio-economic environment. Ecosystems, including their flora and fauna, adapt their behaviour according to water availability and distribution. Seed germination and growth cycles, for example, closely follow the variations in rain and moisture content in soils. Organisms have developed mechanisms to survive long periods of water and food scarcity. People have traditionally adapted their cropping patterns, farming systems, and management of water resources to cope with a dry environment.
Drought regularly occurs in drylands. Some droughts are limited to certain areas, for example a few countries in a region. These ‘local’ droughts are mainly due to deviations in the local weather patterns. They can occur as frequently as every two years but are of relatively short duration. Accordingly, they may have a comparatively small impact on dryland livelihoods. For example in the horn of Africa, during the droughts of 1982-84, 1990-92, and 1996, countries that were particularly affected included Ethiopia, Eritrea, Somalia, Djibouti and Kenya (northern). In contrast, droughts of a ‘regional’ nature affect much larger areas and are mainly due to changes in global weather patterns. Not only are regional droughts more severe than local droughts, usually with a devastating effect on almost all sectors of economies, but they also last longer. An example of such a drought is the devastating Sahelian and much of Eastern African drought of 1968/69. Whatever the nature of a drought, the central issue is the need to develop and implement plans to reduce risks, or minimize the damage associated with a drought.
During their long experience and interaction with environmental uncertainty, dryland inhabitants developed a highly flexible social system and an elaborate set of both individual and collective-based survival strategies that allowed them to effectively utilize the extremely variable environment to minimize loss of livelihoods.
Livestock production systems
These include the following; mobility, herd diversification, herd maximization and splitting of herds. Two types of mobility can be identified. The first is resource utilization mobility, which is a response to unpredictable forage and water availability. The strategy allows livestock herds to make use of the most nutritious forage resources available. The distance covered and the degrees of flexibility vary with year, location, type of livestock and the community. The second type is the drought-escape mobility, which involves long distance migration to evade drought conditions in one locality.
Herd diversification involves maintaining several species/types of livestock. This has ecological and economic advantages. In the dryland nomadic system, largely isolated from national cash economies, surplus stock beyond a ‘basic’ minimum serve as an investment and insurance. The herd plays an important role as risk ‘capital’ during stressful periods, for example during prolonged drought and livestock disease outbreaks. During these times, the herds are spread thinly to reduce the risk of total loss. Further, they are important for post-stress herd rebuilding. Apart from the need to meet household requirements, herds are necessary for building social alliances through transfer of animals to friends and kinsfolk as loans, especially during times of need. This is an essential element in a production system operating in an environment where government insurance or formal banks are non-existent.
Splitting of herds
With increasing dryness, dryland inhabitants split their herds into smaller groups in order to visit different grazing areas simultaneously. Thus, by moving substantial numbers of livestock away from areas of concentration, the rate of use of pastures around dry season water holes is minimized. In effect, each range area is utilized only for a short period such that vegetation resources remain in good condition. Such intermittent use of resources improves forage vigour and growth.
Crop production systems
Drylands pose great constraints to crop production. Yields vary enormously from year to year, and crops frequently fail. Soil fertility, weed infestation and pest incidence fluctuate from place to place. Striga is a typical example of a parasitic weed of sorghum, whose control is very difficult. Locusts and armyworms are common crop pests. For the farmers it is extremely difficult to plan ahead, and cropping is very risky. Crops are grown under rainfed conditions, different traditional forms of water harvesting and flood irrigation, as well as modern irrigation techniques. The risks of environmental damage are generally larger under crop farming than under pastoral conditions. The biomass is low, which lowers the applicability of practices such as mulching and composing. On average, a successful crop is harvested once in every five years.
Food grains and legumes are the basic crops grown by small crops farmers. Most are marginal subsistence farmers, cultivating basic food crops. These include maize, sorghum, millets, cowpeas and pigeon peas. In the higher areas, the grains include wheat, barley and teff. Crop farmers also grow small quantities of oilseeds (sunflower, sesame, groundnuts), root crops (cassava, sweet potatoes), fibres (cotton), fruit and vegetables. Generally, these are varieties that mature quickly under rainfed conditions. Cropping patterns are adapted to local conditions. Crops are often grown in rotation or as intercrops to minimize the risks of drought and to manage soil fertility. Most crops are annuals, intermixed with a few permanent and tree crops. Most crop farmers also keep livestock (cattle, goats, sheep, etc). Herds are small, due to limited available grazing areas. Small livestock are a source of ready cash and a safeguard in times of distress. Livestock provide manure for the fields, either by grazing on the stubble after the harvest, or through composting.
There are great social variations among crop farmers, depending on the different biophysical conditions, the farmers’ skills, the availability of labour, and access to resources outside the farm. These factors also determine whether farmers are ready to invest in their farms and their ability to adapt their farming practices to the new dryland conditions is an important factor for success.
Generally, efforts towards improving dryland farming have focused on the following aspects; (i) Soil and water management through conservation tillage; (ii) Water harvesting and storage for domestic use, livestock, and crop farming; (iii) Micro-management of soil fertility through manuring, composting, mulching; and, (iv) Production of high value market crops under irrigation where the potential exists.
A few specialized groups practice fishing. This is confined to environments of water bodies. Fish is often farmed in reservoirs behind large dams and if water is seasonal, fish species that mature quickly are used. Problems include diminishing stock levels in the natural water bodies and high siltation due to soil erosion causing turbidity and low productivity.
Hunters and gatherers
In periods of extreme drought, a few dryland communities turn to wild fruits and leaves in a bid to cushion themselves from starvation. Hunting and gathering could be said to be extreme activities in today’s world but the reality is that these still act as last options for the poor in drylands, especially when life is threatened by lack of food and water.
Multifunctional role of agriculture in drylands
Agriculture and related land uses continue to play a leading role in drylands economies and societies despite the extreme climatic conditions. However, recurrent droughts and migration from rural areas have decreased the contribution of agriculture to the GDP of these areas. The development of alternative economic options remains dependent on the resource base, on the level of socio-economic development and on the capacity of the countries to create and maintain a diversified economic environment. The "poor drylands" are facing the most serious threats in terms of sustainability of agriculture and land resource management.
A strong competition between agriculture and other land resource uses exists due to constraints imposed by limited water and soil resources. Optimization of these limited resources remains the objective and often a matter of survival for the dryland populations. Many indigenous societies in dryland areas have traditionally enhanced the multifunctional use of land resources by adapting their production systems according to the availability and variability of the natural features. Problems arise when increased pressure on land resources disturbs the delicate balance, thereby jeopardizing the natural capacity of the land to regenerate, leading to inevitable ecological, social and economic consequences.
Vulnerability and adaptation to climate change
According to the Intergovernmental Panel on Climate Change (IPCC, 2001) the vulnerability of tropical developing countries to climate change is likely to be greater, due to low adaptive capacity linked to limited financial and human resources, availability of and access to appropriate technologies, and strong and effective organizations and institutions. Where these are low, vulnerability becomes correspondingly higher.
A key question then is what the impact of global climate change will be on drylands. Predictions have been made, but they are dependent on assumptions and type of models used. For example, Haramata (2001) reported two contrasting scenarios for West Africa. One scenario was that of significant reduction in rainfall, increase in temperature and rainfall variability at the start of the rainy season. The other indicated that the more arid regions would get higher rainfall. Further it has proved difficult to effectively include in the models the effects of phenomena such as El Niño, as well as the effect of dust in the atmosphere.
Capacity to adapt can only be realized, however, if adaptation to climate change is effectively integrated into national economic development plans, with adequate support and goodwill. To date much research has been carried out on climate change in drylands. This has mainly focused on potential impacts on physical and biological systems, while paying little attention to socio-economic systems and development.
A considerable amount of knowledge on the sources and nature of vulnerability in drylands now exists, and the processes are rather well understood. There is fair understanding of the policies needed to underlie investment by dry land inhabitants, e.g. the institutional (rights of access to and control of natural resources), technical (e.g. means of improving productivity of natural resources) and economic (e.g. incentives for investment in improved dry land management. Lack of knowledge is not a major constraint, but it is in many cases poorly distributed. When available, it is not uncommon to find it in forms not easily usable by those in need. Even when these bottlenecks are overcome however, it is common for new knowledge to conflict with traditional practices and power structures within communities and nations, rather than being evaluated and incorporated into local skills and perceptions. This suggests the need for effective and appropriate information and extension services and networks.
Strategies for drylands development - Role of Knowledge
The search for viable and sustainable solutions to address the challenges in drylands Africa has brought into focus a diverse range of approaches and development options, one of which is improving access to and use of knowledge, science, technology and innovation. Potential strategies and likely determinants of success or failure with regard to this challenge are summarized below.
- improve knowledge of drylands and the indigenous communities including traditional agricultural practices
- improve research-extension-farmer (community) linkages and co-operation
- integrate traditional knowledge with innovative technology
- improve stakeholders participation in research, extension, training, awareness and education programmes (e.g. gender, youth, indigenous communities)
Likely determinants of success or failure:
- measurable impact and uptake of extension, training and demonstrations conducted at farmer level / indigenous communities
- number and involvement of farmers / community leaders used as trainers
- number of women and youth involved and impact of their participation
- use of low-impact, simple and self-sustainable technology linked to community knowledge systems
- extent to which extension interventions are adapted to local needs, level of skills and capacity of follow-up through farm tests and pilot schemes
- extent to which indigenous communities are encouraged to innovate on their own
- how readily researchers and research results are integrated into communities and policies.
Policy plays a key role in ensuring that people invest wisely in using available resources sustainably to improve their livelihoods. Large scale policies have generally not worked because they were relied on imported blue prints that lacked the flexibility that people need to survive and prosper in such regions. People’s indigenous knowledge is a valuable resource for managing highly variable and risky environments and building on such knowledge can help identify policies, research priorities for the scientific community and sustainable practices for the resource users. The responsibility for deciding the future of dry land natural resource management must remain with dry land households and scientists and policymakers are encouraged to work closely with them to achieve sustainable impact. Can drylands people, against all odds, reduce poverty and food insecurity, and attain sustainable livelihoods with the support of the scientific community in consultation with policymakers?
By Wellington N. Ekaya, PhD, Dryland Resources Ecologist
College of Agriculture and Veterinary Sciences, Department of Land Resource Management and Agricultural Technology
University of Nairobi,
P.O. Box 29053 - 00625, Nairobi, Kenya.
- FAO. 1984, Land, food and people. FAO Economic and social development series 30. Food and Agriculture Organization of the United Nations, Rome.
- Haramata. 2001. Drylands programme newsletter no. 39. IIED, London.
- IPCC 2001. Climate change 2001. The science of climate change. Contribution of working group I to the second assessment report of the Intergovernmental Panel on Climate Change. Adaptation to climate change in the context of sustainable development and equity. Cambridge University Press, Cambridge, U.K.