M.A. Mohamed Saleem
International Livestock Research Institute, Addis Ababa, Ethiopia
The paper identifies poverty and malnutrition, low crop and livestock productivity, widespread land degradation and underutilisation of some resources as major problems of highlands. To tackle these problems, a systems approach to research has been adapted and research has been conducted under the following themes: intentional food/feed production strategies, feed utilisation strategies, livestock mediated soil, water and nutrient management strategies, and spatial integration of system improvement strategies. Specific experimental work done and results achieved are summarised along with a note on future directions.
Mountain and highland ecosystems are found in every continent. They account for 30 million km2, and encompass an array of topography, flora and fauna as well as human cultural differentiation. More than half the world's fresh water originates in the mountains and the highlands. Managing the land and the water to meet the growing domestic needs upstream and to serve the needs of downstream countries is a major concern of many mountainous regions.
Generally plant and animal communities in the mountains and highlands are more tolerant to stress because of the diversity of species with many survival mechanisms. However, when damaged or stressed beyond a certain point or when key species and soil are removed the mountainous ecosystems can easily become fragile because they need long periods of time to recover. Events that trigger large-scale landscape destabilisation are harmful to both the people of the mountains and highlands and those living downstream. In the past such events did not generally influence the development policies of mountainous countries. As a result, highland farm communities in many countries are enmeshed in a complex of expanding population, declining resources, poverty and environmental degradation. Chapter 13 of Agenda 21 of the UNCED 1992 calls for immediate national, regional and global action for proper management of mountain resources and the socio-economic development of the people dependent on them. The Systemwide Programme on Global Sustainable Mountain Agricultural Development (GSMAD) convened by the Centro International de la Papa (CIP), and the African Highland Initiative (AHI) are CGIAR's response to this call, which aims towards, (a) generating and strengthening knowledge about the ecology and sustainable development of mountain ecosystems, b) promoting integrated watershed development and alternative livelihood opportunities.
ILRI's highlands activities in CG Project 13 are addressing the above issues, focusing on livestock as a means of improving productivity and conservation of natural resources in the mountain and highlands ecologies. These activities are linked with the AHI priority research agenda for the East African highlands. Efforts have also been made to initiate work in the Asian highlands in collaboration with the International Centre for Integrated Mountain Development (ICIMOD). In the Andean region, collaborative work with CIP and the Centro International de Agricultura Tropical (CIAT) is envisaged in the near future.
About 10 percent of tropical Africa lies in the highland ecozone (1500 m asl). Most of the areas are located in the East African region and they support close to half the human and about 30 percent of the total livestock populations. Major problems encountered in the highlands of this region are
poverty and widespread malnutrition
low crop and livestock productivity
widespread land degradation
under-utilisation of some resources due to specific constraints.
Sharp and sudden changes in landforms within short distances (steep slopes, moderate slopes, flatlands and valleys) are very specific to the highlands and the mountains. Rugged terrain limit accessibility, and soils along higher sloping lands are normally shallow. Combination of land forms and soils within short distances have created 'niches', and like in other mountainous regions have contributed to greater biodiversity and a wide variation in land-use. The East African highlands are densely populated and the total livestock population exceeds the support capacity of the grazingland area. Deforestation is common, steep-slope cultivation and overgrazing have become rampant in response to the increasing pressure on land. Fallowing as a means of fertility replenishment has almost disappeared or are ineffective. River courses and water storage bodies are threatened with siltation as soil is eroded and transboundary water-sharing conflicts have increased between countries. The general underlying causes of land degradation in the region, according to some, are government policy failures with particular respect to natural resources tenure and user rights.
The highlands of Ethiopia make up over 60% of the East African highland area and accounts for more than 80% of the agricultural lands. In addition, it serves as the major catchment for many tributaries that feed the river Nile. Agricultural production is in the hands of the peasant sector, and farm technology has undergone little change for hundreds of years. As in other countries in the region, the smallholder farmers in the Ethiopian highlands are poor, individual land holdings are no more than 0.5 to 2.5 ha, family sizes are large, land productivity is low and food requirements are not met. Crop production contributes more than half of Ethiopia's agricultural GDP; the other large contribution comes from the livestock sub-sector. Oxen are the main source of farm power, which is why farmers give a high priority to their care. The most pressing problems for agricultural growth in the country are land degradation, including soil erosion and loss of soil fertility accentuated by the use of dung and crop residues for fuel (which represent an annual loss in crop production of 700,000 tonnes of grain), water resource degradation and loss of biodiversity. At the present rates, it is estimated, land degradation could destroy farmlands of some 10 million highland farmers by the year 2010. Land degradation also contributes to the deterioration of grazinglands. This in turn has contributed to feed shortage due to breakdown of traditional systems of livestock grazing, and to the low performance of livestock. Nationalisation of land in 1975 and subsequent individual and community insecurity has restricted access to land of their choice. In Ethiopia, like other countries in the region, impact of restrictive policies on agricultural production has been recognised, and recent agricultural reforms include measures to: promote private sector involvement and voluntary service co-operatives; strengthen agricultural research and extension; encourage farmer participation; and improvement of farmers' access to roads.
In order to contribute to food security, poverty alleviation and environmental protection in East African and other highlands and mountainous regions, ILRI's highlands research complements AHI regional efforts, and aims to
increase production, household income and welfare
conserve or arrest degradation of natural resources
assess combined impact of technologies on ecological changes and the efficiency with which resources are used for increasing human health at the levels of a farm and collection of farms, village and a landscape.
Recognising human, policy and technical dimensions required for increasing agricultural outputs in a sustainable manner, ILRI adopted a holistic approach to research and collaborates with a number of partners. In order to guide consultations with the different stakeholders, including the farming community, a land-use matrix (Figure 1) was developed. Land potential and land-use practices were found to differ when the gradient and altitude were taken into consideration in the analyses. These parameters also determined the major constraints to improve productivity and arrest degradation of the resource base. Some of the major constraints are
seasonal waterlogging restricted the full use of lands at the lower slopes
land fragmentation, disappearance of fallows, negative soil nutrient balance, low crop/fodder yields, and food deficit in the medium slopes and altitudes
due to increasing population pressure on land for cropping, very steep slopes and high altitudes were found overstocked at the risk of widespread soil erosion.
Figure 1. Land-use practices and major constraints for production improvements in the highlands.
Solutions suggested from various consultations led to the development of different technological options suitable for different 'niches' (Figure 2).
Figure 2. Technological options for land-use improvements and their impact in the highlands.
Technological solutions from on-station and on-farm studies have mainly been carried out at the scale of plots/animal/farm. However, in any year, farmers cultivate many small plots that are spread out over the landscape. Conventionally, highland ecosystems, like any other ecosystems, have been viewed primarily as biophysical systems with geo-chemical and biological functions or at best, as human production systems with product yields or economic returns as the focus. However, changes occurring in one part or 'niche' of the highland ecosystem have impact not restricted to the highlands and extends to the plains. Therefore, inter-relationships between biophysical and human dimensions need to be integrated both spatially and temporally, to identify ways to improve conditions of the ecosystems and human welfare. There are no well tested and accepted methods to integrate biophysical and socio-economic impacts of technology interventions. At present, there are only limited prescriptive guidelines to sustainable mountain/highland development, particularly in the African context. As there is no comprehensive and dynamic framework that could facilitate an interdisciplinary understanding of both society and the habitat, the ILRI team has opted, in 1998, to use the emerging agro-ecosystem health framework for this purpose.
The research has been carried out mainly in Ethiopia, and as smallholder farmers in the highland region are confronted by similar technical and social constraints, research results produced in Ethiopia can be expected to have wide application across highland environments in Africa. The ILRI collaborative research in the highlands (Table 1) can be grouped under the following areas:
intensified food/feed production strategies
feed utilisation strategies
livestock-mediated soil, water and nutrient management strategies
spatial integration of system improvement strategies.
Table 1. Major collaborators in different highland research.
|
|
ILRI: Inter project collaboration |
International collaboration |
NARS |
|
Intensified food production strategies |
Project 8 Debre
Zeit |
ICRAF |
EARO |
|
Feed utilisation strategies |
Project 8 Debre Zeit |
AFRC (Silsoe) |
EARO |
|
Livestock-mediated soil, water and nutrient management strategies |
Project 19 |
AFRC (Silsoe), Upsala University |
EARO |
|
Technology integration and system improvement strategies |
Project 11, 12 |
SG 2000, |
EHNRI, KARI, EARO, Addis Ababa University, FARM, AGRIC, MOA |
Land productivity is low, land holdings are small, household food and feed requirements compared to what an average household can produce are high and crop/forage/livestock biogenetic production potentials are not achieved. Intensification of land-use to increase feed production per unit land (in terms of quality and quantity) and to minimise the effects of seasonal feed availability, without affecting the food production potential of the land, is the major challenge. Associations of food and forage crops have been achieved by manipulating spatial and temporal resource sharing attributes of the crops and forages. Research conducted so far includes:
selection of forages based on growth requirements
assessment of resource (light, water and nutrients) sharing at various spatial and temporal associations of food and forage crops
improved tillage practices for alternative cropping schemes
assessment of nutritive quality and quantity of usable feed by harvest time
household land allocation for different crop–forage mixtures to balance year round grain and feed requirements.
Forages from the genus Trifolium, Vicia, Lablab, Vigna, Sesbania etc suitable for highlands have been identified and integrated into cropping systems as inter-, relay or alley crops. Cereal (wheat, oat, maize, sorghum) grain yields, in some cases, have increased in association with forages, but generally did not significantly differ when grown as inter- or sole crops. Greater benefit was however obtained in the amount of feed per land unit. For example, the total fodder yield from local wheat amounted to 2.1 t/ha. Replacing it with improved wheat produced 4.4 t/ha. When improved wheat was sown between Sesbania alleys and followed by grasspea after harvesting the wheat, total fodder production increased to 10.2 t/ha with a corresponding five-fold increase of crude protein content (1520 kg/ha per year) in harvested herbage compared to sole wheat crop (362 kg/ha per year). The study also demonstrated a higher water use efficiency of 160 1 kg-1 DM during the growing period when Lablab forage was sown alone or when improved wheat was sown in Sesbania alleys followed by grasspea, compared to 770 l of water used per kilogram of local wheat when planted as a sole crop.
Several legumes (e.g. Trifoliums) when included in 1 to 2 year rotations were found to benefit the subsequent cereals in the range of 55 to 155 kg/N per ha. Given the recommendation of 80 to 100 kg/fertiliser N for e.g. wheat, growing of a cereal crop will be a substantial economic benefit. In another experiment, wheat yields after 3 years of Lablab and Sesbania-Lablab combinations were, on average, 1.7 t/ha of grain and 2.9 t/ha of straw without N application. To attain similar yield levels, 75 N kg/ha was required on plots that were devoted to growing wheat continuously.
Ex-ante analysis has revealed that, compared to pure cereal stands, crop–forage inter-cropping, while causing a change in the pattern of labour and animal power use, significantly increased the gross margin and cash income. These returns were further enhanced when crop–forage mixtures were combined with crossbred cows for milk production. These clearly indicate a potential for the intensification of land-use at different altitude and slopes.
Available feed for livestock is inadequate. Seasonality and inter-year variability in feed quality and quantity aggravate feed shortage. Even if feed production can be improved, what are the relative nutritive values for livestock; when, what type, how much and in what form (fresh, wilted, dried, chopped etc) the feeds can be supplemented? What should be the feeding package for dairy cows or small ruminants (fattened strategically for markets) or for draft animals (to keep them in good body condition before the onset of the ploughing season)? These questions are addressed in this area of research. We are also studying whether crossbred dairy cows can perform multiple functions (milk production and draft power) without the reproductive ability over life span being affected.
On-farm work is contributing to farmer adoption of feed supplementation strategies to enable the use of cows for multiple tasks to increase farm income, and to potentially reduce (on-farm) number of animals required for different tasks. Resource allocations, in terms of labour and land, between those farmers using crossbred cows for both dairy and draft, and those using them only for dairy, are similar. Use of crossbred cows for traction did not affect milk yield and lactation length, and reduced by 20% time required for the first cultivation and 24% and 19% for the second and third pass, respectively. In general, farmers seem reluctant to use crossbred cows for traction, fearing greater stress, particularly for the first pass on a hardened and dry soil. An anthropological survey suggested that, those farmers who believe that crossbred cows can also plough are better educated, have slightly smaller households and considerably smaller crop and grazing lands and herd size. Cultural and social reasons are not often stated for the unwillingness to use cows for traction, though they may be important, and often relate to the division of labour between men and women.
Members of households who owned crossbred cows on average consumed 17% more calories, 24% more fat and 13% more protein than members of households without crossbred cows. The households with crossbred cows spent about 7% more on food purchases, and in addition, they allocated more land to growing high-protein pulses and consumed about 30% more pulses. The anthropometric measurements indicate that introduction of crossbred cows could significantly improve human nutrition and health. By the end of the first survey, stunting of children (height for age) was found to be less than half as prevalent in households with crossbred cows (20%) as in those households with local cows (43%).
Nutrients are lost from production systems through harvested products, and purchased inputs for nutrient replenishment are often expensive. Efforts to improve livestock production in smallholder farming systems include the efficient use of crop residues and manure, and introduction of herbaceous/tree forage legumes. This has opened up opportunities for managing nutrients in the production system through
in-situ recycling nutrients through manure
accumulation and spatial concentration of nutrients
planted fallow and leys.
What is the quality of manure, how does it vary seasonally and with feeding strategies (e.g. grazing vs penned); what weed species accumulate, through undigested seeds, when crop fields are manured and what is the impact of these species on crop yields or in changing specie composition in grazinglands? How much manure will be required, and what are the complementary effects of mixing manure and inorganic fertilisers on crop nutrient uptake? How long will the application effects of manure last in the soil and how much of the applied nutrients be retained in surface and sub-surface water? What are the relative benefits of natural and planted fallow to livestock and to food crops that follows the fallow? These are questions addressed in this area of research.
In the highlands, livestock are spatially and temporally associated with grazinglands and croplands. Livestock spend considerable amount of time on croplands, particularly after grain harvest, grazing crop residues, recycling nutrients and compacting the soil. Croplands are periodically ploughed and fertilised, while actions of the hoofs of grazing animals are accumulated, often compacting the grazinglands. Common grazinglands, are not fertilised to improve biomass productivity. With increasing cultivation of steeper slopes, livestock are pushed further onto very steep slopes. Hence, lands where animal graze during the cropping season are overstocked and overgrazed. Hence, soil structural changes under varying grazing pressure influence soil erosion, and water infiltration, retention, sub-surface flows and run-off rates. An understanding of the influence of grazing on biophysical processes, including vegetative and hydrological changes, is a pre-requisite to develop better resources management strategies for intensification of mixed crop–livestock systems in the highlands.
Some parts of the highlands, particularly the lower slopes and valleys where clayey soils like the Vertisols dominate, waterlogging is a major constraint for cropping. The heavy clayey soils are difficult to work, and animal-drawn implements that farmers have are not versatile enough to meet the cultivation requirements, such as inverting soil, to make seed beds that can facilitate drainage. Developing simple animal-drawn land shaping implement to improve drainage of poorly drained soils was also a major focus under this research area. Other long-term investigations in this research area include:
assessment of seasonal variation in grazing pressure, potential biomass production and biomass availability
vegetative cover, run-off rates, soil erosion and soil water infiltration
biomass requirements for meeting grazing demands and soil protection at varying slopes
surface and sub-surface faunal and floral diversity
grazingland productivity with and without the manure deposited during grazing.
An animal powered broadbed maker (BBM), adapting elements of the traditional 'maresha' plough is a major output of this research. Animal body condition, and power generated by animals when pulling the BBM were measured to assess work output. A monitoring equipment to measure physiological parameters of animals during work has been developed in conjunction with this work.
Preparation of broadbeds and furrows (BBFs) using BBM improved drainage of Vertisols. These soil types are normally found in lower slopes and valleys and often remain waterlogged during most of the growing season. Making BBFs improved drainage which allowed early sowing of crops, followed by another crop sown later in the season after harvesting the first crop. This has opened up opportunities for growing different crop/forage types and their combinations in the same year. Across sites and years, mean yields of wheat grain increased by 23% to 120% (depending on the severity of waterlogging problems of Vertisols), when drainage was improved by using the BBF land management system compared to the traditional land preparation method.
In areas where BBF is the traditional land preparation method to facilitate drainage, use of animal-drawn BBM to shape the land relieved women and children from the strenuous task of making the BBF with hand. Studies have also shown that the farmer is willing to invest in a BBM, and that BBF system is sustainable under farmer management as long as inputs and credit for the purchase of seeds and fertiliser are available when needed. Several NGOs, including Global 2000, have promoted this technology, and according to extension workers more than 25,000 BBM are in use across Ethiopian highlands. Assuming that 25% of the Vertisols are under wheat crop, replacing it with an early planted improved variety on drained Vertisols could potentially increase wheat production to 5.22 million tonnes as opposed to 1.26 million tonnes from improperly drained Vertisols.
At very high grazing pressure (4.2 AU/ha:AU=380 kg), manure deposited approximately amounted to 7 tonnes/ha/yr, which is equal to 100 kg N/ha and 20 kg P/ha. Where manure was left on the grazed plots, the biomass production increased after three years with increase of grazing pressure and reduced the soil erosion by about 75% compared to previous years. The biomass production continued to decline over the three year experimental period and soil erosion was well in excess of the permissible amount in the grazed plots from which manure was removed.
Livestock grazing studies are establishing the dynamics of seasonal biomass production at different slopes and, the grazing intensity and level of vegetative cover required to maintain soil loss below the tolerance limit. It appears that feed shortage for grazing livestock can be averted by better synchronisation of grazing with seasonal herbage availability at different slopes. Strategic application of fertiliser could also improve biomass productivity and meet both the grazing and soil protection requirements for vegetative biomass. Once land is degraded its restoration will be much more costly than employing prudent management of biomass on sloping lands, which includes maintenance of soil fertility by resorting to the application of chemical fertilisers or recycling manure. Improved vegetative cover also contributed to higher water infiltration and retention along steeper slopes. This could have a significant effect on household access to water sources during the dry season.
Grazing, choice of crop and livestock species, place and duration of farming etc exert varying pressures on the environment and induce changes (which may be smooth, sudden or erratic) in the quality and quantity of natural resources. The society has to respond to such changes through environmental, economic and sectoral policies. To be able to assess the changing 'state' of resources in agro-ecosystems, it is necessary to separate human-induced impacts from those that occur naturally through interactions of climate and terrain. The challenge is to develop/promote systems that are capable of conserving the resources while contributing to meet the needs of the community.
Understanding of the production processes, identification of the right species, use of inputs and improved techniques have helped with several new options for increasing crop–livestock productivity and conservation of natural resources. Livestock is mobile, and therefore could influence many land-use systems within the same landscape. Implications of food security and human welfare go beyond the individual farms. Hence, to serve the multiple needs (grain, feed, draft power, markets, external water flows, drainage, land conservation etc) of communities, different land-use systems will have to be compatibly integrated at a landscape level. Appropriateness and economic viability of the different component technologies for land-use improvements will also have to be tested. Appropriate policies need to be in place to enable farmers to adopt new technologies in the development and management of common resources. These concerns led to the following research activities
evaluation of the combined effects of selected technologies, described in the previous sections, at the watershed scale
community participation in resources management
application of bio-economic model to assess options for resources use at a watershed scale.
Since 1994, ILRI is collaborating with a research consortium of national and international research and development agencies to improve land-use and production systems within a pilot watershed located at Ginchi, Ethiopia. On the recommendation of a team that evaluated the Ginchi watershed work in 1996, work has also started in 1998 at another watershed located at Cheffe Donsa which represents a higher altitude and different land use in contrast to Ginchi.
Improvement in human welfare in the watershed is anticipated through the aggregate output resulting from introduction of new technologies that can bring changes to crops and cropping pattern, livestock management and grazing practices and manure use, water management etc. Currently, technologies being tested involving farming communities in the watershed are animal-powered BBM for land shaping, forage-based cropping, and grazing practices. In the future, efforts will also be intensified to study the enabling processes that need to be put in place to combine/refine/quantify the impact of other technologies such as dual purpose cows and nutrient and water management strategies on the productivity and health of the watershed ecosystem and the community.
Main outputs of this research so far include an analysis of land-use changes over a period of 40 years using aerial photographs and digitised maps. Farmers using the BBM in the Ginchi watershed have changed to high yielding wheat from teff, which was the main crop grown on the waterlogged Vertisol areas of the watershed prior to 1994.
Several years of on-farm studies showed that Vertisol drainage technique is economically beneficial, but its adoption by individual farmer creates negative externalities as water drained from one farm compounds the waterlogging or land degradation problems of the neighbouring farms. This can be avoided if farmers collectively plan the construction and maintenance of common drainage channels. The possibility of community approaches/participation in resources management was studied in the Ginchi watershed. Results show that leadership and private interests play a major role in the individual contribution to a common good. In the case of Vertisol management, construction of the common drainage channel is an example of such a common good. The level of farmer participation in the construction of the drainage channel was directly related to the extent of land owned in the watershed, and to the extent of land owned that was near the drainage channel.
This study aims to carry out an ex-ante impact assessment of a natural resources management package for Vertisol when applied within Ginchi watershed area in the Ethiopian highlands. The framework of analysis is a bio-economic model that integrates biophysical factors with social, economic and policy factors. Linkages between objectives of biophysical and socio-economic sustainability of the Vertisol technology in relation to the rest of the land use within the watershed, and how they can simultaneously be achieved through adoption of this technology package is the expected output. The structure of the bio-economic model generated in this study enables one to test, a priori, the impact of various components of the package on cash income, food security, human and animal nutritional balance, and physical and biological degradation of land. It will also enable us to examine the performance of the technologies under various policy scenarios and highlight the role of livestock in food security and environmental protection.
In the highlands, traditional agricultural practices are no longer sustainable because of increasing population pressure and disruption of social systems. The highland ecosystems are also progressively deteriorating, indicated by the depletion of forest, natural grass cover, biodiversity and soil nutrients. As the threat to global environment has now become a major concern, management of natural resources for the sole purpose of increasing agricultural commodities can no longer be a research goal unless it is linked to the maintenance of natural resources base and environmental safety.
Natural resources management should start with the analysis of factors contributing to differences within production systems. Individual components and their interactions at different production levels, e.g. farm and community, region etc are also influenced by the socio-economic and policy goals, and they need to be studied further. The long-term capacity to provide for the household needs depends on the restorative power of the natural resources available on the farm. Otherwise, the farmer has to substitute resources or intensify use of other resources to make up for the loss of productivity from one of them. Changes in soil resources, at the plot level, affect the internal processes (including sub-surface) and therefore, affect the production rate and stability of the type of land use. Activities likely to have adverse effects on a broader scale will however become important national concerns for the long-term use of the resources to meet food security targets. Hence, one of the major challenges for resources management research is to harmonise individual economic considerations and individual resources use objectives with those of the entire community.
Agro-ecosystems are complex, but their complexity is largely attributable to the interaction of socio-economic and ecological processes. To evaluate agro-ecosystems and to aid in the improvement of those systems their ultimate impact on the people who depend on them will have to be considered. Therefore it is important that criteria to provide the basis for the comparison of systems and to interpret changes within the landscape (target area) in time are developed. Data and technologies for improved production and resources conservation generated through ILRI's collaborative research, are expected to complement other regional and global NRM efforts. The agro-ecosystem health framework incorporates principles to evaluate social, economic and biophysical stability, resilience and diversity of systems. ILRI hopes to use this framework, starting in 1998, to integrate data from different regional highland sites. We believe this will allow inter-regional information exchange and technology transfer for the sustainable use of highland resources worldwide.
