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4.1.1 Objectives

A comprehensive inventory of the grazing resource base, and an assessment of the environmental effect of present use, are essential to understand the character and status of the current pastoral system; which, in turn, are prerequisites for identifying or validating development opportunities.

Assessing current use and status involves a combination of historical, contemporary and projected data sets, and will:

4.1.2  Forage resource characteristics

General land use and forage resource inventory

Forage resource data - areas, yields, utilization levels, proper use factors, quality indices, condition and patterns of use - should be compiled at the lowest planning unit practicable. Tables should list all forage resources, including every grazing unit contributing to the forage supply plus any "intensively" developed and "external" sources. Forage resources include natural and improved grazing lands (frequently classified according to vegetation type or season of use), hay and silage, fodder crops, crop residues, and supplementary feeds such as grain or by-products.

Data representing single years, or means of years, should be presented in tables, whereas the interpretation of time-related data is simplified by graphical representation. Wherever possible, a range of values should be given rather than simple means, and the applicability of the forage data sets to a year of "normal" climatic conditions noted and accounted for during analyses. Historical land use statistics should be compiled to facilitate the interpretation of forage resource trends.

Examples of tabulated forage resource data are presented in the case studies of Chapter 6. Examples of graphical representation of proportional composition of land use classes for a series of planning units, and the relative contribution of each forage-source type to livestock forage intake are shown in Figure 7. The predominance of grazing over other land uses is highlighted in Figure 7a, while 7b shows the importance of Mountainous Dry Steppe and Alpine Meadow to forage supply within grassland types. It is emphasized that the second figure is based on estimates of livestock forage intake, rather than production, because this more accurately represents the importance to livestock production of different forage sources.

Production patterns and dynamics

"Static" forage resource data sets, representing a single year, for example, are a reasonable base for interpreting the relationships of components of the forage supply, but are generally inadequate for planning sustainable management programmes.

Figure 7. Examples of grassland forage resources (from IFAD, 1993b)

Figure 7a

Figure 7b.

The seasonality of environmental parameters affecting grassland growth determine the pattern and potential for livestock production. Short growing seasons, constrained by moisture and temperature, lead to inefficient conversion of solar energy into livestock products because of the need to carry over much of the forage for consumption after the growing season. Large quantitative and qualitative losses of forage occur that significantly affect the system-level effectiveness of development options.

Examples of the characteristics of a grazing-based livestock production system are presented in Figure 8. The modality and variability of rainfall and temperature patterns (Figures 8a and 8b), limit forage growth to between 150 and 230 days (Figure 8c) so about half of livestock forage requirements are beyond the growing season (Figure 8c). Standing herbage in winter is too poor to provide adequate feed so, in spite of feeding conserved forage (crop residues in this case), there are significant losses in livestock condition (Figure 8d).

Direct indicators of grassland condition and trend, especially from the viewpoint of overgrazing or degradation, include the following (based on FAO, 1991c; Heady and Heady, 1982; Pressland and Graham, 1989):



Condition and trend assessment are used to identify the occurrence of over-grazing, or resource degradation, and as evidence of the reversibility of degradation Where poor condition, or a trend of degradation, is said to be occurring, it must be established whether this is part of the natural processes of the environment, or due to inappropriate pastoral use. Objective information is often lacking, and trends in condition and productivity frequently have to be inferred; this carries the risk of transcending information quality limits and should be done with great caution.

If direct indicators, such as forage productivity, botanical composition, ground cover and soil erosion, are used to determine condition and trend, then data must be presented to indicate the state of the grassland relative to what is perceived as "good" condition. It is inadequate to describe grazing land as in poor condition because ground cover and productivity is "low." That may be a natural characteristic of the area. Blanket statements describing grasslands as "seriously degraded" or "on the verge of ecosystem collapse" are valueless without evidence.

In the absence of direct evidence of condition and trend, abstract or secondary evidence has to be used. Indirect indicators of the character, condition and trend of grasslands include:

Figure 8.  Examples of seasonal characteristics of a grassland-based livestock production system, Qinghai, China (IFAD, 1993b)

Figure 8a.  Monthly rainfall variation (1989 to 1990)

Figure 8b.  Monthly temperature variation

Figure 8c.  Profile of forage supply (pasture and forage crops) relative to livestock forage intake.

Figure 8d.  Occurrence of forage shortages, conserved forage feeding and poor livestock condition (Based on 16 interviews).

As many indicators as possible should be considered during the assessment, and conclusions drawn from those which offer substantial and convergent evidence.

If grazing land has been subjected to increasing livestock populations (increasing forage demand), areas which have had grazing pressures reduced experimentally can indicate the type of historical changes in grassland condition that may have occurred (providing ecological thresholds have not been crossed). Pilot and demonstration livestock management areas are suitable examples; exclosures (i.e. areas where livestock has been permanently excluded) are useful in botanical studies, but are not necessarily indicative of such trends, as exclosures are grazing/no grazing situations for which vegetation changes are often quite different from grazing/increased/decreased grazing responses.

Analysis of historical trends in livestock populations give an insight into changing pressures on grasslands, but not necessarily of degradation, especially when changes in the patterns and levels of forage utilization are not taken into account. Livestock population increases may be a reflection of changes in actual grazing area because of disease control (e.g. tsetse-fly control in Africa) or the establishment of watering points. When interpreting livestock population data, care is necessary, since pastoralists often make misleading declarations. If adequate methods are not available to account for the different feed requirements of livestock types and classes, mixed livestock population statistics may be converted to standard livestock units, which helps to reduce distortions caused by variations in herd or flock composition over time.

Decreases in livestock productivity per head (breed vigour and disease effects excepted) may indicate that nutrition has worsened and, by inference, that populations have increased and/or grassland production or herbage dietary quality has declined. This is not necessarily the case, since changes in spatial and seasonal patterns of livestock feeding and management may reduce the overall quality of forage on offer, and cropland expansion can lead to grazing being replaced by poorer quality crop residues.

Examples of trends in livestock numbers are presented in Figures 1 and 9. Figure 9 is interesting in that the apparent rise in numbers after 1985 was, in part, attributed to a 5% increase in livestock declaration per annum.

Local opinion on trends in grassland condition is often reliable, but sometimes changes are misinterpreted or misstated, such as in an attempt to justify development. The yield data presented in Figure 9 are from an area where decreases of 35 to 64% were claimed for recent decades, but the data do not support the supposed trend.

A further factor affecting vegetation trends is illustrated in Figure 9c. Productivity had undoubtedly decreased, but local opinion was influenced by the memory of "abundant grass in the wadis" during the 1950s, when, as the figure shows, rainfall was higher than "normal." The data also suggest that rainfall had not decreased over the last few decades, as was locally believed and often used to explain decreasing productivity.

It is essential to consider inter-year variability in forage production when assessing livestock carrying capacities, grazing management policies and the environmental sustainability of pastoral activities. Unfortunately, forage variability data are rarely available, so an estimate may be made based upon local rainfall data and DM production × rainfall regressions for similar climatic conditions.

Regressions of DM production on rainfall, for a series of regions and climatic zones, are presented in Figure 5. The regression for the zone most like the project area may be used to convert local historical rainfall data to a DM equivalent and the result then statistically analysed to derive a coefficient of variation to apply to local estimates or measurements of "average-year" DM production; conversely the local DM production for a year of known rainfall can be converted to DM production for the average year. This technique has shortcomings - the assumption of normal distribution of data in particular - but is often the only practicable method of incorporating variability into forage production information, and ultimately into estimates of livestock carrying capacity.

Grassland recovery potential is the likely response of overgrazed or degraded vegetation to reduction of grazing pressure. It is used to assess the viability of management interventions involving the manipulation of livestock numbers or grazing pressures. The form and degree of response of vegetation to such changes depends on complex ecological and managerial interactions, so field evidence of net responses is essential if the information is to be used for development planning.

Figure 9.  Examples of indicators of grassland resource trends

Figure 9a.  Trends in livestock numbers, expressed as "sheep units" (IFAD, 1993b)

Figure 9b.  Grassland yields 1956 to 1991 (IFAD, 1993b)

Figure 9c.  Rainfall trends, Amman Airport. Normalized distribution. (IFAD, 1993a)

The responses of vegetation to changes in grazing pressure depend on the combined effect of the status of the vegetation relative to thresholds, responses of individual plants to grazing, and the degree of hysteresis. These responses were discussed in Chapter 2. Evidence of vegetation responses to modifications in grazing pressure can be seen in:

4.1.3 Livestock carrying capacities and forage-livestock relationships

Several approaches, or methods, can be used to estimate carrying capacity and to investigate forage-livestock relationships (based on Vallentine, 1990):

Modelling, more than any other technique, provides an opportunity to understand the complexity of a pastoral system and is, therefore, consistent with the "new paradigm" of grassland ecosystems. It provides fast, repetitive evaluation of forage resource and livestock data at both component and system levels. Analyses spanning time can be carried out, incorporating variability and realistically representing the complex interactions within the system. The pastoral resource assessment model, RAPS, is described in detail in Chapter 5.

Relatively simple forage balances can give an indication of the state of a grassland-based livestock production system. Because of their dynamic and complex nature, however, few grasslands have the potential to be in a state of "balance," especially in the drier and more climatically variable areas ("non-equilibrium" systems) where forage balance according to "optimal" use is transient and where much of the traditional, extensive livestock sector is based.

Traditional balance assessment is based on forage DM supply and standardized livestock forage DM requirements; this has the advantage of simplicity but its results are often misleading. A simple DM balance takes no account of the significant qualitative differences between forages, seasonal patterns of forage availability, and differences in livestock feed requirements due to physiological state of the animal and forage characteristics, nor does it account for carryover losses. The use of metabolizable energy (ME) overcomes some of the major shortcomings of the traditional DM-based balances, primarily by incorporating forage quality.

If computer-based models are not available, and forage balances based on ME cannot be used, then the following refinements to the traditional "DM-standard livestock unit" balance technique are recommended:

Livestock Carrying Capacity.

Carrying capacity estimates are subject to controversy (Behnke et al., 1993), particularly for the method of calculation, over-simplification of complex systems and regarding carrying capacity as a static entity. Estimates are often presented with little regard to their relevance to livestock production in the pastoral system, nor to their implications concerning sustainability of forage resource use. They often assume a static system and, almost invariably, "average" or "normal" forage production levels. This might be acceptable in a pastoral system in equilibrium (often in humid or sub-humid zones) but has no relevance to non-equilibrium systems of semi-arid environments.

When the forage resource of a pastoral system is constantly in a state of flux because of extreme rainfall variability (with moisture a major factor limiting plant growth), it is difficult to manage livestock numbers to avoid "over-" and "under-" stocking in successive years. The converse - managing the forage resource to "smooth" out inter-year fluctuations in forage supply using "conservative" stocking rates - is just as difficult in extensive pastoral systems.

In non-equilibrium systems, fluctuations in forage production, and therefore levels of livestock feeding, are normal. When the flux in forage production reaches a weather disaster, livestock die and grazing pressure is reduced. The long-term sustainability of the system relies on the resilience of the vegetation and the delayed recovery of livestock numbers in the years following a severe weather event.

Comparison of the livestock numbers relating to the status quo and optimized scenarios, gives an indication of the level of over- or under-stocking, provided that inter-year variability of forage production is taken into account. This, in turn, indicates the scale of intervention that may be required to achieve a sustainable production system.

Carrying capacity must be estimated critically to ensure that the conclusions are realistic. Single factor assessments, such as those based on DM, may overlook other important factors that have an impact on the sustainability of the grazing ecosystem or on livestock production. Examples of such factors are nutrient depletion at the system level, changes in livestock water supplies, or limiting dietary components, such as protein, minerals or trace elements. A critical assessment of all factors influencing carrying capacity is therefore important (Table  4). Misrepresentations of levels of overstocking are common. Unless circumstances are unusual, estimates of overstocking by more than 35 to 65% are unrealistic and indicate incorrect assumptions or methodology.

The degree of conservatism in carrying capacity estimates depends upon the level of inter-year variability of forage production. Where there is little variation, the mean annual forage production may be used as the basis of calculations, but in highly variable systems, production values well below the mean may be more realistic. Despite controversy, if carrying capacity estimates are realistic and reflect system dynamics, they are extremely useful in management and development planning.

Table 4.  Natural and managerial factors affecting carrying capacity (based on Vallentine, 1990)

Natural factors

Management factors

Climate and weather including inter-year and seasonal variations
Water table
Root zone depth
Soil texture and structure
Soil fertility
Soil salinity
Physiography of area
Quantity of vegetation
Quality of vegetation
Amount and distribution of drinking water
Location of shade
Fire hazard
Wild herbivores

Livestock type e.g. differences in foraging behaviour
Effects of historical use
Grazing distribution
Meeting drinking water needs
Nutrient depletion due to pastoral activities
Season of grazing
Type of grazing animal
Effects of other livestock
Grazing system
Cultural treatments, e.g. weed control, fertilizer, seeding and irrigation
Disease control
Operational objectives
Markets and marketing

Patterns of forage-livestock relationships

Field indicators of forage-livestock relationships are:

Actual analyses of "balance" are used to assess the state of forage-livestock relationships within a system, indicating seasonal patterns of forage surpluses and deficits. In general, two forms of analysis are required. The first illustrates the status quo and relates the forage intake of "non-optimally" fed livestock to the current forage resources, harvested at present levels of use and with current livestock numbers. The second relates "optimally" fed livestock to the current forage resources, used at optimal levels, with livestock numbers adjusted until "balance" is achieved and carrying capacity is indicated. For many pastoral systems the state of "balance" can only be transient so interpretations of balance must be done in the context of overall system dynamics relating to a number of years. The transient nature of "balance" within an arid environment is illustrated in Figures 23 and 25, in Chapter 6.

Typical seasonal forage-livestock "balances" for a single year are shown in Figure 10. In the examples, the "balance" point is not "zero" forage availability but is related to the profile of residual DM, determined by the forage utilization limits (shown as "unavailable"). The second chart in Figure 10 indicates the timing and extent of a forage deficit.

Seasonal patterns of forage supply and livestock forage intake vary considerably according to environmental conditions, pastoral resource endowment and forms of pastoral production. Examples of patterns in contrasting climatic conditions, moist temperate and Mediterranean environments, are given in Figure 11. In these examples, the seasonality of available grazing is shown, along with inputs of conserved forage (hay, wheat, by-products, etc.), the timing of which mainly reflects harvest dates. Seasonal shortages of fresh grazing are indicated where the "livestock" line is above the "grassland and pasture" line. Such shortages are covered by standing forage from periods of surplus, and by the use of the conserved forage. In the first example, grazing is the major feed, whereas, in the second, conserved fodder is the major source. Clearly the substantially different character of the examples affects their management and development opportunities. Other patterns of forage supply and livestock forage intake are illustrated in the case studies of Chapter 6.

Figure 10.  Examples of forage "balance"

Forage supply approximately in "balance" with requirements

Forage supply in deficit relative to requirements

Figure 11. Examples of seasonal pattern of forage supply relative to livestock forage intake

Temperate, moist environment

Mediterranean environment

Identification of critical features and land-unit-specific imbalances

Examination of the seasonal pattern of the forage-livestock relationship gives an insight into the timing and extent of forage deficits (Figure 10) and therefore the type and scale of development interventions that might be appropriate. The seasonal pattern of the forage-livestock relationship will indicate the timing, quantity and quality of additional forage required to cover any deficits, or conversely the level of reduction required in livestock numbers.

Comparison of trends in the production or use of the major forage types can indicate changes in the nature of the livestock industry and therefore the type of development that may be required. This is illustrated in Figure 12, indicating how, over recent decades, livestock numbers increased and the major forage source for grassland-based livestock shifted from grazing land to imported concentrates. This process put the grazing lands under so high a pressure that their rehabilitation and development was impracticable without restructuring the industry (IFAD, 1993b).

Figure 12.  Examples of forage-livestock relationships

Trends of livestock feed imports relative to livestock forage requirements (1970-1992)

Example of the extent of current use of hay and crop residues and according to proposed full utilization of hay and crop residues (shown as bars), both relative to livestock forage requirements.

Appraisal of the grazing versus conserved forage groups for the status quo and in the light of proposed development can reveal potentially serious deficits in forage quality. An example, shown in Figure 12, indicates unrealistic expectation of the extent to which crop residues could be incorporated as a year-round forage source. Coarse crop residues are only used as a forage in winter, whereas high quality summer grasses support most of the livestock production. Extension of crop residue use into the summer would therefore not be tenable.

Comparative analysis of the grazing pressures between land units provides an opportunity to identify critical units that may constrain production of the system as a whole. These critical units may be identified by relating actual livestock densities per land unit to forage production and use data, and to field assessments of land condition. Data for such an assessment are derived from grazing management records (see Appendixes) and analysis of forage balances.

In grassland systems where there is a climatic and topographic separation of seasonal grazing lands, the long-term impact of grazing is not spatially homogenous, due to differences in botanical composition, productivity, grazing tolerance and grazing pressures. Imbalances between seasonal grazing lands can be aggravated by the conversion of grazing (usually winter) to cropland, and by the encroachment of afforestation and urbanization.

Imbalances may be detected by modelling the forage resources over time and by field monitoring of condition and trend. A seasonal imbalance can be identified by summing, separately, the net forage supply of land units, comprising each seasonal grazing land, and comparing their proportional contribution to total supply with "optimal" livestock forage requirements for the corresponding period. The correction of imbalances either requires the strategic development of pastures or fodder crops, or a re-allocation of grazing lands with respect to period of use.

"Improvement" may induce an imbalance between grazing lands, or between grazing lands and other feed sources. In a mountain environment, for example, one grazing area may be more suited than others to improvement of its vegetation, or improved management. There is, therefore, a risk of focusing upon that site to the detriment of the rest. A re-allocation of land resources between traditional grazing lands, or some form of complementary development, may have to be incorporated in the development programme to avoid a negative impact.

As mentioned in Chapter 2, the level of inter-year variability of forage production has a profound effect on development opportunities. This relates not only to the overall levels of sustainable livestock production but also to the form of grazing management required and the success rates of forage development options. This variability will be difficult to modify, but there may be circumstances where it can be reduced by manipulating the ratios of forage resource types, using introduced forages and irrigation. Some forms of pasture "development" may make the level of inter-year variability of forage production worse; such as introduction of so-called "improved" forages with higher potential production but greater susceptibility to drought.


4.2.1 Objectives

Before identifying development options, the need for "development" should be justified in terms of environmental sustainability, livestock production and the welfare of local people; it is invariably associated with decreasing grassland productivity, environmental decline, increasing human and livestock population pressures, or a combination of these factors.

From the viewpoint of production and use of forage resources, the mechanisms of grassland development are:

While the above "direct" interventions are often the primary focus of development, the general condition of the livestock industry and production system frequently constrain or distort production and therefore may have to be reviewed. Indirect interventions might include importing to compensate for shortfalls in livestock products or livestock feeds; reducing demand for livestock products; or reducing non-fodder croplands, especially in marginal areas.

Grassland development options are inextricably linked to livestock production and are often perceived from the livestock viewpoint. Drought management, a primary issue of the semi-arid and arid zones, is a good example of this. It incorporates a wide range of development components including maximized grazing distribution, sale of stock as soon as drought is foreseen, formation of an efficient breeding herd with fewer unproductive animals, use of special purpose pasture, expansion of the area available for grazing, strategic sale of livestock, and use of supplementary feeds.

4.2.2  Development options

Development interventions include: grazing management; reseeding; fodder crop and shrub cultivation; use of crop residues; supplementary feeding; fertilizer application; weed, pest and disease control; water resources development; use of fire; bush clearing; erosion control; and restriction of inappropriate concurrent uses. Common grassland development components are discussed below, and prioritized according to climatic zones in Table 5 (see page 48).

Workable grazing management policies for extensive grazing are difficult to formulate and implement; they have to accommodate both the intra-year seasonal patterns of forage supply and frequently high inter-year variability. Socio-economic constraints often hinder otherwise viable technical options. Grazing management issues were discussed in Chapter 2. Management systems are generally based upon various forms of rotational or sequential grazing with inter-grazing resting.

The prerequisite of all grazing management systems is to have sustainable stocking rates over the long term; the actual form of management is secondary to this. In overgrazed areas, the overall issues relating to "optimizing" livestock numbers relative to the forage resource must be given priority. Any other form of development is conditional upon livestock numbers being consistent with the forage supply.

Management programmes often recommend the strategic resting of grazing land to facilitate natural seeding of the grasses, thereby enhancing longevity of the stand. Some points to consider in relation to designing grazing management programmes in perennial grasslands are (Sindelar, 1988):

Grazing land improvement through reseeding with grasses and legumes is an option for the more humid zones, provided livestock, soil fertility and management issues are resolved. Seeding programmes, particularly in drier climatic zones have often proven economically and technically impractical, especially where control over traditional rights and grazing access is limited. Active re-vegetation of degraded grasslands with an annual cool-season rainfall of under 350 to 400 mm (borderline for rainfed cropping) may not be justified on economic grounds, even with free labour. Only periodic resting to re-vegetate such areas is technically and economically viable (IFAD, 1992b). Reseeding grazing land is expensive and, unless the factors that brought about the degradation are rectified, results can only be ephemeral. Even where increasing fodder production on cropping land is successful, there is seldom sufficient (if any) reduction of grazing pressure on the adjacent grazing to facilitate development.

Climatic factors, primarily low and erratic precipitation and extremes of temperature, have an overriding effect on the success or failure of re-vegetation and seeding programmes, regardless of the intensity of treatments used to prepare seedbeds and control undesirable plants. If reseeding is considered seriously, the frequency of occurrence of favourable establishment conditions must be taken into account in development planning. For example, favourable establishment conditions are estimated to occur in one year out of four in semi-arid regions of Australia. Similarly, in the Great Basin of USA, the limited precipitation may only allow natural or artificially induced seedling establishment once or twice every 15 years (Call and Roundy, 1991).

Grassland improvement options are almost always based upon the advantages of having a high proportion of perennials in the system. Despite widespread disappointing results, the low potential in drier environments for the re-establishment of perennial species is often ignored. In contrast, annuals are vigorous establishers and strong competitors for water and nutrients and therefore warrant greater attention in such environments (Breman et al., 1984).

Seeding by over-sowing or direct drilling provides an alternative to complete seedbed preparation where the erosion hazard is high, where the preparation of a complete seedbed is impractical or where the purpose is to modify rather than replace the present stand. Inter-seeding is a compromise between slow natural reseeding and the theoretically quicker establishment expected from complete seedbed preparation.

The theoretical contribution of nitrogen to grassland soils through biological fixation by legumes is often used as the justification for legume introduction and rhizobia inoculation programmes. The potential of legumes to fix nitrogen is well proven, but it is not universal. Extreme climatic and edaphic conditions are often not conducive to N-fixation by rhizobia and the expected benefits of legume inoculation may not materialize.

Intensive pasture development is an option for moister environments or where irrigation is available. It usually involves the complete replacement of native grassland species with so-called "improved" high yielding grasses and legumes. The forages may be introduced after the complete destruction of resident vegetation by cultivation then drilling or over-sowing, or by direct drilling (sod seeding) into an existing sward controlled by grazing or herbicide application. Intensively managed pastures are useful for providing strategic grazing, priority feeding of livestock classes such as young or pregnant stock, or for conservation as hay or silage. They are usually managed on some form of rotational grazing designed to optimize overall productivity by controlling grazing period and intensity, and re-growth between grazings. This option is only viable where soil fertility is high, whether naturally or with added fertilizers, and local pasture and livestock management skills are sufficient.

Fodder crop production is often considered a key to reducing excessive grazing pressures on grasslands. This usually involves the growing of grasses or legumes to be conserved as hay or silage, and used for special purpose or strategic feeding of livestock. High quality fodder may have a significant impact on the overall livestock diet. Trials in Australia, Africa and Pakistan have shown that the strategic use of even quite small amounts of high quality forage will enhance the digestibility and increase the intake of other poor quality forage (FAO, 1988). The successful development of improved forage resources is increasingly related to the provision of fodder banks, or the inclusion of forage legumes in the cropping systems of agropastoralists who farm small pockets of moister and higher fertility soils in otherwise arid areas. The value of fodder crops depends on their ability to reduce seasonal forage deficits, at least for priority classes of livestock. Even if sufficient area is available for their growth, the usefulness of leguminous forages may be limited by the capacity of pastoralists to conserve the forage (IFAD, 1992b).

Alternatives to fodder crops include the growing of fodder shrubs and trees in special purpose stands, or along fence or boundary lines. Fodder trees and shrubs are generally expensive and require careful management. In theory, they have potential in semi-arid lands; however, this is not often proven in the context of traditional livestock husbandry (FAO, 1992). The extent of adoption of the technique has been disappointing, probably because of the labour and management requirements. However fodder trees and shrubs have a niche, especially if they are multipurpose, contributing to erosion control and fuelwood supply, in addition to fodder (IFAD, 1992b).

The use of coarse crop residues for winter or dry season feeding of livestock is long established and widespread. Cheap techniques such as urea treatment, chopping and mixing with high quality forages can improve their intake and dietary quality significantly. Locally produced industrial by-products and processed feeds are often used for special purpose supplementary feeding in some areas, including fishmeal, oilseed cake and compound feeds based upon cereals.

The yield response of grassland to chemical fertilizers containing nitrogen or phosphorus is well known. However, the technique is generally considered uneconomic and therefore livestock managers are not inclined to fertilize extensive grazing. In agropastoral areas, if fertilizer can be afforded, it is applied to crops. Special purpose pasture may be fertilized to overcome strategic forage shortages. For example, in some environments, nitrogen may be used to enhance end-of-season production and extend the growing season.

Herbicides are available for weed and shrub control on grasslands, but economics and risk of environmental pollution often prevent their use. Grassland pests, the most notable being the locust, often make a serious impact on the forage supply. Rodents may impose a greater impact on the plant community than the more conspicuous livestock. High rodent populations are commonly associated with grasslands in poor condition. Use of herbicides and chemicals for disease control (e.g. against tsetse fly populations to control trypanosomiasis) is carried out, but can have negative effects on wildlife, water supplies (surface and groundwater) and vegetation (World Bank, 1991)

Large predators exert an indirect effect on use of grazing land. Their presence changes the pattern of grassland use, causing some areas to be overused while other areas are underused. They may force a shift in the class of livestock used in the area, such as a shift to cattle on an area primarily suited to sheep grazing. Cordon fences across large tracts of grassland are used to prevent the spread of pests, predators and diseases between areas. Examples of such fences are found in northern Namibia (FAO/IFAD, 1992) and Australia. Predators may also make night-penning necessary, thus reducing grazing time.

Availability of drinking water on grazing lands affects levels of utilization and livestock distribution. The provision of water sources, such as wells or temporary ponds, is generally more relevant in arid and semi-arid environments. Risks associated with the provision of watering points include overgrazing of adjacent areas and the assurance of water supply and water quality. The provision of watering sites to facilitate the expansion of grazing into areas historically ungrazed may increase livestock production in the short term, but be unsustainable in the long term. There is often no assurance that newly accessible areas will not become overstocked and degraded through inadequate management.

Fire is a very old tool for manipulating grazed vegetation. It has been used to control undesirable vegetation, to prepare sites for planting and seeding, to control plant diseases, to reduce the risk of uncontrolled fire, to remove senescent coarse vegetation and allow grazing access, and to improve forage yield and palatability.

Erosion control - thereby maintaining or improving the capacity of an area to produce forage - is a major issue affecting the sustainability of grazing systems. In some areas, erosion has been a feature of the landscape for centuries because of the underlying geology, and is not necessarily linked with inappropriate management, for livestock or other uses. Such areas should be identified to ensure that they are not targeted inappropriately for erosion control programmes.

It may be necessary to restrict inappropriate concurrent uses because of their negative environmental impact and associated reduction of forage resources. Such uses include the cultivation of marginal land, fuelwood harvesting, charcoal making, and collecting medicinal plants.

Negative forage-livestock imbalances are most often identified as the primary production constraint and addressed using direct interventions such as those discussed above. However, it may be possible to manipulate the general conditions of the livestock industry and production system to increase efficiency of livestock production and reduce grassland forage demand. Indirect strategies include (based on Hallam, 1983):

While these factors may offer opportunities for manipulation, they must be assessed rigorously for potential negative environmental and economic impact, both within and beyond the livestock industry.

4.2.3  Identification and selection of development options

The process of identifying viable development options is an integration of technical, environmental, political, economic and social factors. Particular attention has to be given to land use and forage production potentials, and constraints that operate within the area. Constraints must be defined according to whether they are fixed or variable and if they can therefore be manipulated. Constraints involved in grassland development are usually associated with (Dickie and O'Rourke, 1984):

The identification or verification of local environmental, managerial and technological constraints to grassland and fodder crop production can be facilitated by the use of questionnaires that list component issues and invite subjective rankings of their importance. The component issues include factors that affect edaphic conditions, plant species choice, grassland and fodder crop management and use, grassland improvement techniques and control of counterproductive agents.

Each component issue can be assessed for environmental impact, scope for improvement and potential economic impact, likelihood for improvement through research and development, government priority, importance to farmers, livestock owners and managers, and urgency for improvement. Responses to the questionnaires might be sought from local government offices, research and development institutions, universities, field stations and state farms; their results should be analysed in parallel with the results of detailed interviews with pastoralists.

Identification of forage development options is, to a certain extent, conditioned by climatic zone. In humid temperate and sub-humid areas, the main development emphasis has been on providing high quality feed (often legumes) to complement poor quality pasture and coarse roughage, and forage seed production. In contrast, in semi-arid and arid areas, development emphasis has been given to improving fodder conservation, fodder trees and grazing systems. The use of nitrogen-fixing legumes is considered important in all these climatic zones (FAO, 1992). In general, opportunities for grassland improvement through plant species introduction are greatest in the more humid zones, whereas grazing management is important across all zones, and is the primary option in arid areas.

The relevance of the principal grassland development components to each climatic zone is shown in Table 5. The table is presented for general indications of development suitability and not to specifically include or exclude certain development options. Local climatic characteristics, such as seasonal temperature and rainfall patterns, and cultural and socio-economic influences often override development opportunities that are indicated by the general climatic zone classification.

Table 5.  The suitability of grassland development components according to climatic zones









Grazing management






Grassland seeding (artificial)





Intensive pasture development





Fodder crops






Crop residues






Supplementary feeds






Strategic use of fertilizer on grassland





Weed, pest and disease control





Water supply development






Use of fire






Restriction of inappropriate uses






Note:  (1) Without irrigation

To ensure relevance and sustainability, grassland and fodder crop development options have to be identified within the context of the following key factors (White, 1988; Vallentine, 1971):

Frequently the first suggestion in grassland development is the implementation of "improved livestock management" involving a reduction of livestock numbers. There are few, if any, instances where this has been successfully demonstrated. Therefore, unless there are very unusual circumstances, this is not a viable option (Behnke, 1984).

In degraded grasslands, degradation will not be halted, nor opportunity for rehabilitation occur unless the factors which continue to promote the degradation cycle are removed (Pressland and Graham, 1989).

It is essential that compelling local evidence be available on viability of the proposed development option. Locally inspired options clearly have the greatest opportunity for success and so should be given priority consideration. Development possibilities from outside of the area should, without exception, be first evaluated as small-scale, field trials with target group participation.

For the reasons outlined above, emphasis should be given to identifying development options based on detailed and extensive field interviews with pastoralists, and utilizing local government grassland and forage research development experience.

Technological solutions may require a major revision of local grassland management practices. This may not be suited to participating pastoralists, so it is often prudent to focus on the promotion of small modifications to traditional systems, that act as catalysts for development in a direction that may lead to the adoption of greater technological opportunities. This "system component modification" approach will facilitate the pathway for development and not enforce a premature and high-risk end-point. In this way the system will evolve within the producers' current knowledge, capabilities and participation. Furthermore, in grazing lands where political or population factors overwhelm the possibility of sustainability, small-scale interventions represent the only practicable option.

Clues to practicable development options of the "component modification" type may be found in local practices of forage production that have arisen spontaneously; if these are relatively widespread they are obviously suited to the socio-economic and environmental conditions. Assessment of factors limiting expansion of the particular technique may reveal development opportunities; for example, current production of a fodder crop may be increased by devising ways to improve yield per unit area, by increasing the area sown or assuring a better seed supply.

Figure 13.  Examples of grassland forage development projections

Figure 13a.  Proportional increments in total forage production within project counties (IFAD, 1993b)

Figure 13b.  Contribution of each development component to total forage production (IFAD, 1993b)

Figure 13c.  Estimated trends in forage balances for each county of a Project Area (FAO 1991a)

Note: a value of +1 indicates a forage surplus equal, in magnitude, to the forage requirement (i.e. supply:requirement = 2:1).

4.2.4  Forecasting impact of development on forage production

Forecasts of the effect of development must be conservative and reflect realistic estimates of yield increases and development scale; they should incorporate the following:

Profiles of incremental yields incorporating the factors listed above, which are easily composed using spreadsheet tables; should span the year prior to implementation through to year 15 or 30 (depending upon the environment). The "with-project" forecasts are overlaid with equivalent "without-project" trends so that the net effect of the project can be appraised.

Examples of forecasts of grassland forage resource development are presented in Figure 13. In the first example, proportional incremental yields for project counties are shown. The use of proportional rather than absolute yields is useful when comparing relative increments between sub-areas or if original DM yields are suspect. The second example illustrates the contribution of each development component to total production over 20 years. A "without project" trend is overlain. In the third example, forecasts of forage balance for each county within a project area indicate the likelihood of a widespread forage shortage after about seven years. A shortcoming of the trends presented is the lack of upper and lower estimates.

If data quality is adequate, then parallel forecasts should be made for a representative range of target groups/households to illustrate likely impact of development at the individual recipient level. Sensitivity analyses should be carried out.


4.3.1 Prerequisites

Institutions that are either directly or indirectly involved in fields related to grasslands should be drawn upon to contribute. Such institutions specialize in grassland survey and development, ecology, pedology, land use capability, soil and water conservation, dune control, forestry, water resources, and include agricultural colleges and universities and remote sensing laboratories. It is inevitable that institutional bias will effect data quality. Bias may be within an institution or between institutions, and arise from competition for funding or from professional jealousies. It is essential to be aware of such conditions.

Historical information on research and development programmes extending beyond those that are current, or of the immediate past, often reveals highly relevant information of successes and failures. Sometimes, activities similar to those proposed may have already been tried, failed and forgotten or ignored. An example of this was a proposal for grassland re-seeding in an area with a 30-year history of unsuccessful grassland development research (IFAD, 1989). Positive reports of the outcome of past development activities have to be verified. Often a grassland development programme will be reported as successful merely because the mechanics of the programme had been completed. For example "1 000 ha of grassland drilled with legume X" tells nothing of the outcome.

It is often advantageous to seek out retired professionals for independent opinions on development issues; they have a wealth of experience and can provide valuable information on historical trends and development issues.

Inadequate or over-committed resources are a common factor in project failure. The resources and capacities of institutions that will be involved in the implementation and management of the project must be thoroughly assessed to confirm their capacity for undertaking such work. The assessment should include institutional structure, staffing, current work programmes, facilities and equipment, and linkages with other organizations.

Conversely the resources required by the project must be assessed in detail to ensure that the proposals are practicable in respect to the institutional resources expected to be available. The assessment should not only include professional and technical input, labour and materials, but also consider the timing of inputs and their relationship to other, concurrent, commitments. This will ensure that seasonal peaks in manpower inputs (e.g. for site establishment and field surveys) will not exceed the available resources.

While "external" technical services often facilitate project implementation, an ongoing dependence upon such services (national or foreign) throws doubt on the sustainability of the project. This dependence is reduced by providing training programmes for local staff (FAO, 1991b). In pastoral systems, priority should be given to applied rather than academic training, which often results in too high a level of specialization and does not equip the candidate for dealing with the wide range of complex and inter-related issues typical of extensive grasslands. Mechanisms must be in place to ensure that knowledge and technical skills are passed on within the project.

As described previously, the involvement of the pastoralists and farmers in the description of the grassland and livestock resources, identification of constraints to production and in formulating development options is fundamental to project design. Target group input and participation must continue through the project design and implementation stages. There is evidence (Akabwai, 1992) that, despite increased specification of the "participatory roles" of pastoralists in project documents, their actual participation remains very limited. A truly participatory development model often requires a major divergence from the traditional project design path.

Political and economic conditions must be conducive to the implementation and long-term support of the programme. National livestock production targets must be consistent with forage resources, markets, economics and target group management skills.

4.3.2  Design considerations

Opportunities and constraints relating to the project rationale should be clearly identified and described. The opportunities range from the technical options for increased sustainable forage production, to market opportunities. In opposition are the constraints currently or potentially preventing exploitation of opportunities.

Design components to be addressed include (FAO, 1991b):

During initial design of the project, boundaries should be set in relation to the grassland and fodder crop production system, and not arbitrarily according to physical size or handy topographical features. In migratory or transhumant pastoral systems, it is essential to identify the physical expanse and ecosystem types that livestock exploit over a "drought-to-drought cycle" and in particular the land and water resources that are critical to the overall production system. Loss of access to lands due to, for example, agronomic encroachment, settlement programmes and creation of national parks will affect the sustainability of those well established pastoral systems (World Bank, 1991). In nomadic or transhumant systems, incorporation of all areas of the system into a project may be difficult because of political boundaries and their complexity and degree of overlap with adjacent systems. However, unless there are compelling reasons, it is inappropriate to exclude physically separate seasonal grazing lands from the project area.

The most successful projects go through an initial learning phase before identifying or concentrating on a particular package of measures that are viable and can be replicated; this phase is often taken for granted under the usual economic appraisal approach. How packages are identified and replicated has to be specified. There is often an imbalance between how interventions are identified and the large effort devoted to estimating likely benefits (Moris, 1986).

4.3.3  Risks and environmental impacts

The environmental impacts of the development programme, either positive or negative, have to be anticipated and described during project design. This should include provision for correction of any negative impacts that arise during implementation. Potential negative environmental impacts, based on a list compiled by the World Bank (World Bank, 1991), are presented in Table 6 (at the end of this Chapter). Increases in livestock populations resulting from improved veterinary care, disease treatment and control, and increased breeding rates may cause increased grazing pressures on grasslands unless these interventions are carried out in parallel with forage development programmes. Unbalanced development programmes are likely to cause deterioration of grassland by shifting excessive pressures to non-target areas. For example, the establishment of fenced areas with reduced or controlled grazing use may force livestock onto other, more vulnerable areas.

External impacts on grassland may arise from development activities such as agriculture, water resource development, settlement programmes and mining. Use of herbicides and chemicals for disease control may have negative effects on wildlife, water supplies (surface and groundwater) and vegetation. Where projects provide supplementary forage to maintain livestock during droughts, care must be taken that the supply continues until the grassland vegetation has adequately recovered from the drought. A misconception is that once rains begin, supplementary feeding can be discontinued, but the lag time between the onset of rains and recovery of grassland production must be accounted for. Considerable damage can be done to grasslands by turning livestock out too early (World Bank, 1991).

The question of whether the proposed interventions are robust enough to withstand the expected level of risk should be discussed in relation to the worst- and best-outcome scenarios. By the very nature of the environment, all grassland improvement practices are subject to both success and failure. Quantitative and qualitative assessments are necessary to ensure proper evaluation. This level of follow up, particularly after failure, is rarely carried out in development projects. Development failures are linked with poor design, poor implementation, practices unsuited to conditions and unpredictable natural catastrophes.

4.3.4  Monitoring

The project must be designed so that monitoring is an integral and ongoing component, extending beyond the official project term. Monitoring should incorporate assessment of the impact of the project on grassland condition, and therefore its environmental sustainability. The programme must monitor those environmental risks that were identified, so that any negative impact of the project can be detected as early as possible and alleviation measures implemented.

Examples of factors that should be monitored in a grassland development programme are (based on World Bank, 1991):

Table 6.  Potential negative environmental impacts of grassland-based livestock production, and corresponding potential mitigating measures (based on World Bank, 1991)




Degradation of vegetation resources due to overgrazing.

Revise assessment of carrying capacity. Limitation of animal numbers.
Control length of grazing time on particular areas.
Mix livestock species to maximize use of vegetation resource.
Re-seeding and fodder production.
Strategic placement of water points and salt.


Increased soil erosion due to grazing, clearing of vegetation and trampling.

Increased salinization of surface waters.

Restriction of livestock access to unstable areas (e.g. steep slopes).
Soil erosion control measures (e.g. afforestation, re-seeding of grasses, land preparation, terracing).

Deterioration of soil fertility and physical characteristics through:

removal of vegetation
increased erosion
soil compaction

Restriction of livestock access to unstable areas (e.g. steep slopes).
Soil erosion control measures (e.g. afforestation, re-seeding of grasses, land preparation, terracing).

Increased rapid runoff due to vegetation clearing and soil compaction (decreased infiltration capacity)

Water conservation measures and water spreading.
Restrict livestock access to unstable areas (e.g. steep slopes).
Soil erosion control measures (e.g. afforestation, re-seeding of grasses, land preparation, terracing).
Limit animal numbers.
Control length of grazing time on particular areas.
Mix livestock species to maximize use of vegetation resource.
Re-seeding and fodder production.
Cut and carry.
Strategic placement of water points and salt.


Degradation of vegetation and soil around water points.

Over-tapping of groundwater.

Lowering of water table and degradation of vegetation locally by drilling and use of boreholes.

Excessive salts.

Development of many small-capacity water sources.
Strategic placement of water points.
Control of use of water points (animal numbers and time of year).
Closure of permanent water sources when temporary pools and streams are available.
Limitation of well capacity by choice of technologies (e.g. hand pumps or buckets instead of motor pumps).


Displacement and reduction of wildlife populations by reduction of habitat.

Disruption of migratory routes.

Competition for food and water resources.

Introduction of diseases

Impacts of burning

Increased poaching and killing of wildlife considered as pests or predators on livestock

Plan and implement grassland management strategies (choice of species, livestock numbers, grazing areas) that minimize impacts on wildlife.
Establish compensatory wildlife refuges.
Establish management of wildlife ranching, which will help protect wildlife resources.
Careful planning.
Provide access routes, gates or stiles if needed.


Pollution, environmental disruption and health hazards from disease and pest control measures

Choose a chemical that is species-specific, with short residue time (active period), and has low impact on other biological resources.
Provide protective measures for field workers.
Use spraying methods and timing to minimize potential for water pollution.
Select disease-resistant livestock breed.


Displacement of human population.
Resettlement conduct in other areas

Examine alternatives through community consultation.

Interference with traditional rights of access to resources or travel routes

Provide alternatives or accommodate in clearing.

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