By 2030, crop production in the developing countries is projected to be 67 percent higher than in the base year (1997/99). In spite of this noticeable increase in the volume of crop production, in terms of annual growth rates this would imply a considerable slowdown in the growth of crop production as compared with the past, for the reasons discussed in Section 1.2.2 concerning the anticipated deceleration in the growth of aggregate demand. Most of this increase (about 80 percent) would continue to come on account of a further intensification of crop production in the form of higher yields and of higher cropping intensities (multiple cropping and reduced fallow periods), with the remainder (about 20 percent) coming on account of further arable land expansion.
The developing countries have some 2.8 billion ha of land with a potential for rainfed agriculture at yields above a«minimum acceptable level». Of this total, some 960 million ha are already under cultivation. Most of the remaining 1.8 billion ha however cannot be considered as land«reserve» since the bulk of the land not used is very unevenly distributed with most of it concentrated in a few countries in South America and sub-Saharan Africa. In contrast, many countries in South Asia and the Near East/North Africa region have virtually no spare land left, and much of the land not in use suffers from one or more constraints making it less suitable for agriculture. In addition, a good part of the land with agricultural potential is under forest or in protected areas, in use for human settlements, or suffers from lack of infrastructure and the incidence of disease. Therefore, it should not be considered as being a reserve, readily available for agricultural expansion.
Taking into account availability of and need for land, arable land in the developing countries is projected to increase by 13 percent (120 million ha) over the period to 2030, most of it in the«land-abundant» regions of South America and sub-Saharan Africa, with an unknown but probably considerable part of it coming from deforestation. In terms of harvested land, the land area would increase by 20 percent (178 million ha) on account of increasing cropping intensity. The latter will reflect, inter alia, the growing role of irrigation in total land use and crop production.
Irrigation is expected to play an increasingly important role in the agriculture of the developing countries. At present, irrigated production is estimated to account for 20 percent of the arable land (but about 30 percent of harvested area because of its higher cropping intensities) and to contribute some 40 percent of total crop production (nearly 60 percent of cereal production). This share is expected to increase to 47 percent by 2030. The developing countries are estimated to have some 400 million ha of land which, when combined with available water resources and equipped for irrigation, represent the maximum potential for irrigation extension. Of this total, about one half (some 202 million ha) is currently equipped in varying degrees for irrigation and is so used. The projections conclude that an additional 40 million ha could come under irrigated use, raising the total to 242 million ha in 2030. In principle, by that year the developing countries would be exploiting for agriculture some 60 percent of their total potential for irrigation. Naturally, the harvested area under irrigation will increase by more (33 percent), following fuller exploitation of the potential offered by controlled water use for multiple cropping.
Expansion of irrigation would lead to a 14 percent increase in water withdrawals for agriculture. This latter result depends crucially on the projected increase in irrigation water use efficiency (from 38 to 42 percent on average). Without such efficiency improvements it would be difficult to sustain the above-mentioned rates of expansion of irrigated agriculture. This is most evident in regions such as the Near East/North Africa (where water withdrawals for irrigated agriculture account for over 50 percent of their total renewable water resources) and South Asia where they account for 36 percent. In contrast they account for only 1 percent in Latin America and 2 percent in sub-Saharan Africa, with East Asia being in the middle (8 percent).
Naturally, these regional averages mask wide intercountry differences in water scarcities. Countries using more than 40 percent are considered to be in a critical situation. There are ten developing countries in that class, including countries such as Saudi Arabia and the Libyan Arab Jamahiriya which use more than 100 percent of their renewable resources (mining of fossil groundwater), and another eight countries are using more than 20 percent, a threshold which could be used to indicate impending water scarcity. By 2030 two more countries will have crossed this threshold and by then 20 developing countries will be suffering actual or impending water scarcity. Within-country differences can be as wide as intercountry ones. Large regions within countries can be in a critical situation even if the national average withdrawals for irrigation are relatively modest. China is in that class with the north facing severe constraints while the south is abundantly endowed with water.
As already mentioned, yield growth will remain the mainstay of crop production growth. For most crops, however, the annual growth rate of yields over the projection period will be well below that of the past. For example, the growth rate of the average cereal yield of the developing countries is projected to be 1.0 percent p.a., as compared with the 2.5 percent p.a. recorded for 1961-99. This deceleration in growth of yields has been under way for some time now. For example, in the last ten years (1991-2001) it was already down to 1.4 percent p.a. Intercountry differences in yields are wide and are projected to remain so. They reflect in part differences in agro-ecological conditions and in part differences in agricultural management practices and the overall socio-economic and policy environment. To the extent that the latter factors change (e.g. if scarcities developed and prices rose), or can be made to change through policy, yields could grow in the countries where the agro-ecological potential exists for this to happen under changed agronomic practices, e.g. better varieties and fertilization.
Chapter 11 provides some illustrative evidence on the existence of such potential in the different countries. It does so by comparing the prevailing yields with those that are attainable under advanced (or high-input) agriculture in those parts of the land that are evaluated as being suitable for the individual crops from the standpoint of agro-ecological conditions. Naturally, the existence of such gaps in yields in no way suggests that countries with yields well below their agro-ecologically attainable ones are less efficient producers economically. Often, the contrary is true. For example, the major exporters of wheat (North America, Argentina and Australia) have low to medium yields well under their attainable ones under high input farming. Yet they are competitive low-cost producers compared with some countries attaining much higher yields, often near their maximum potential, e.g. many countries of the EU.
In conclusion, the yield growth foreseen for the future, although lower than in the past, can still be the mainstay of production increases and need not imply a break from past trends in the balance between demand and supply of food at the world level. This could be so precisely because the demand will also be growing at lower rates. The issue is not really whether the yield growth rates will be slower than in the past. They will. Rather the issue is if such slower growth is sufficient to deliver the required additional production.
Naturally, this slower yield growth may not happen unless we make it happen. In particular, the higher yields of the future cannot come only, or even predominantly, from the unexploited yield potential of existing varieties in the countries and agro-ecologies where such potential exists. It will need also to come from countries and agro-ecologies where such potential is very limited. This requires continued support to agricultural research to develop improved varieties for such environments (including those coming from modern biotechnology, see Section 1.2.5 below).
The preceding discussion may have created the impression that we are saying that there is, or there can be developed, sufficient production potential for meeting the increases in effective demand that may be forthcoming in the course of the next three decades. The impression is correct so long as it refers to the world as a whole. But this is not saying that just because such global potential exists, or can be developed, all people will be food-secure in the future. Far from it, as already discussed. Food and food production potential are however closely related in poor and agriculturally dependent societies. Many situations exist where production potential is limited (e.g. in the semi-arid areas given existing and accessible technology, infrastructure, etc.) and a good part of the population depends on such poor agricultural resources for food and more general livelihood. Unless local agriculture is developed and/or other income-earning opportunities open up, the food insecurity determined by limited production potential will persist, even in the middle of potential plenty at the world level. The need to develop local agriculture in such situations as the often sine qua non condition for improved food security cannot be overemphasized.
In the same vein, the above-mentioned need to continue the agricultural research effort (including in biotechnology) to improve yields, even if yield potentials of existing varieties are not fully exploited in many countries, finds its justification in these same considerations. For example, the existence of significant unexploited yield potential for wheat in Ukraine or Argentina does not obviate the need for research to raise yield ceilings for the agro-ecological and other conditions (e.g. salinity and water shortages) prevailing in the irrigated areas of South Asia. The bulk of the additional demand for wheat in South Asia will not be for the wheat that could be potentially produced in Ukraine or Argentina. It will materialize only as part of the process of increasing production locally for the reasons discussed earlier (increased production stimulates the local rural economy).
Behind all these statements, of course, looms large the issue of whether the continuing intensification of agriculture that proceeds even under decelerating yield growth rates is a sustainable proposition. That is, is the capacity of agriculture to continue to produce as much as is needed for all people to be well-fed now and in the future being put in jeopardy, e.g. because of land degradation, depletion or otherwise deterioration of water resources. Would the externalities generated in the process of agricultural expansion and intensification (e.g. water and air pollution, disturbance of habitat, loss of biodiversity, etc.) not impose unacceptable costs to society? An overview of these issues is given in section 1.2.9 below, and the issues are treated in more detail in Chapter 12. The technological options to minimize risks and transit to a more environmentally benign and resource-conserving agriculture, while still achieving the needed production increases, are explored in Chapter 11. Here suffice to say that we foresee a rather drastic slowdown in the use of mineral fertilizer.
Fertilizer use (nutrients NPK) in the developing countries is projected to increase by 1.1 percent p.a. from 85 million tonnes in 1997/99 to 120 million tonnes in 2030 (at world level from 138 million tonnes to 188 million tonnes). This is a drastic slowdown as compared with the past (e.g. 3.7 percent for 1989-99). The slowdown reflects the expected continuing deceleration in agricultural production growth, the relatively high levels of application that prevail currently, or will be gradually attained, in several countries, and the expected increase in fertilizer use efficiency, partly induced by environmental concerns. Fertilizer use per hectare in the developing countries is projected to grow from 89 kg in 1997/99 to 111 kg in 2030 (near the current level of use in the industrial countries). East Asia would continue to have the highest consumption, reaching 266 kg per ha, while sub-Saharan Africa would still have under 10 kg/ha in 2030, well below what would be required to eliminate nutrient mining and deterioration of soil fertility in many areas.
Significant changes are expected to occur in the mechanization of agriculture which will change the role played by the different sources of power in land tilling and preparation: human labour, draught animals and machines. There is currently wide diversity among countries and regions as to the role of these three power sources. Human labour predominates in sub-Saharan Africa (some two-thirds of the land area is cultivated by hand) and is significant also in Asia, both South (30 percent) and East (40 percent - the estimate for East Asia excludes China). In contrast, it is mostly tractor power in Latin America and the Near East/North Africa. Draught animals account for shares in total power supply comparable to those of human labour in all regions except sub-Saharan Africa, where their use is much less common.
The future is likely to see further shifts towards the use of mechanical power substituting for both human labour and draught animals. The driving forces for such changes are part of the development process (e.g. urbanization and opening of alternative employment opportunities) but also reflect more specific factors pertaining to agriculture and particular socio-economic contexts. These include changes in cultivation methods (spread of no-till/conservation agriculture, change from transplanting to broadcast rice seeding, etc.), in cropping patterns and in some factors affecting the rural workforce such as the impact of HIV/AIDS (an important factor in several countries of sub-Saharan Africa). Only in sub-Saharan Africa will human labour remain the predominant source of power. This is also the only region where draught animals are likely to increase their share, with tractors cultivating no more than about a quarter of the total crop area even in 2030. This compares with shares of 50-75 percent that will have been reached in the other regions.
The spread of science-based agriculture emanating from the significant past investments in agricultural research underpinned much of the growth of agriculture in the historical period. The need for further increases in production in the future while conserving the resource base of agriculture and minimizing adverse effects on the wider environment, calls for ever greater contributions from agricultural research. The research agenda for the future will be more comprehensive and complex than in the past because the resource base of agriculture and the wider environment are so much more stretched today compared with the past. Research must increasingly integrate current advances in the molecular sciences, in biotechnology and in plant and pest ecology with a more fundamental understanding of plant and animal production in the context of optimizing soil, water and nutrient use efficiencies and synergies. Effective exploitation of advances in information and communication technology will be necessary not only to facilitate interactions across this broad spectrum of scientific disciplines but also to document and integrate traditional wisdom and knowledge in the planning of the research agenda and to disseminate the research results more widely.
Much of the additional production must originate in the developing countries and at least part of it must originate in the agriculture practised by the poor in ways that will also contribute to raising their incomes and food demand as well as those of the wider rural economy. It follows that the research effort must be increasingly oriented in three directions, namely, that it must:
These considerations, particularly the last two, suggest a growing role for public sector research. Yet support for public sector research (both national and international) has declined significantly over the past decade at a time when private sector investment in biotechnology research has been growing fast. By now the private sector has built up expertise, technologies and products that are considered essential to the development and growth of tropical agriculture based on rapidly advancing biotechnologies and genetically engineered products. It follows that potential synergies between the private sector and public research offer significant scope for directing more of the research effort in the above-mentioned directions. In particular, such synergies can lead research to underpin a new technology revolution with greater focus on the poor by putting special emphasis on those crop varieties and livestock breeds that were largely ignored throughout the green revolution, but that are specifically adapted to local ecosystems. These include crops such as cassava and the minor root crops, bananas, groundnuts, millets, some oilcrops, sorghum and sweet potato. Indigenous breeds of cattle, sheep, goats, pigs and poultry and locally adapted fish species must also receive much greater priority. A particular focus in the new research agenda should be on plant tolerance to drought, salinity and low soil fertility since nearly half of the world's poor live in dryland regions with fragile soils and irregular rainfall.
The experience to date suggests that biotechnology, if well managed, can be a major contributor to all three objectives. Modern biotechnology is not limited to the much publicized (and often controversial) activity of producing genetically modified organisms (GMOs) by genetic engineering, but encompasses activities such as tissue culture, marker-assisted selection (potentially extremely important for improving the efficiency of traditional breeding) and the more general area of genomics.
The GM crops most diffused commercially at the moment incorporate traits for herbicide tolerance (Ht) or insect resistance (Bt, from Bacillus thuringiensis), while maize and cotton combining both Ht and Bt traits (stacked traits) have also been released recently. Ht soybeans dominate the picture (they account for 63 percent of total area under GM crops and for 46 percent of the global area under soybeans), followed by maize, cotton and canola. Diffusion has been very fast although concentrated in a limited number of countries. The United States accounts for over two-thirds of the 53 million ha under GM crops globally. These first-generation GM crops have not been bred for raising yield potential, and any gains in yields and production have come primarily from reduced losses to pests. They have proved attractive to farmers in land-intensive and labour-scarce environments (primarily the developed countries) or those with a high incidence of pests because they save on inputs, including labour for pest control.
The interest for the developing countries even of these first-generation GM technologies lies in the fact that they embody the required expertise for pest control directly into the seeds. This is particularly important for environments where sophisticated production techniques are difficult to implement, are simply uneconomic or where farmers do not command the management skills to apply inputs at the right time, sequence and amount. The spectacular success of Bt cotton in China (higher yields, lower pesticide use and overall production costs, greatly reduced cases of human poisoning) may bear witness to the usefulness of these GM traits for the agriculture of the developing countries.
The potential benefits can be enhanced by further innovations currently in the pipeline in the general area of pest control. These include herbicide tolerance and insect resistance traits for other crops such as sugar beet, rice, potatoes and wheat; virus-resistant varieties for fruit, vegetables and wheat; and fungus resistance for fruit, vegetables, potatoes and wheat. Even more interesting could be the eventual success of current efforts to introduce into crops new traits aimed at enhancing tolerance to abiotic stresses such as drought, salinity, soil acidity or extreme temperatures. Attempting to raise productivity in such situations using GM varieties can be the cheaper, and perhaps the only feasible, option given the difficulties of pursuing the same objective with packages of interventions based on existing technology.
The transition from the first to the second generation of GM crops is expected to shift the focus towards development of traits for higher and better quality output. Many of these new traits have already been developed but have not yet been released to the market. They include a great variety of different crops, notably soybeans with higher and better protein content or crops with modified oils, fats and starches to improve processing and digestibility, such as high stearate canola, low phytate or low phytic acid maize, beta carotene-enriched rice (“golden rice»), or cotton with built-in colours. First efforts have been made to develop crops that allow the production of nutraceuticals or«functional foods», medicines or food supplements directly within the plants. As these applications can provide immunity to disease or improve the health characteristics of traditional foods, they could become of critical importance for an improved nutritional status of the poor.
However, not all is bright with the potential offered by biotechnology for the future of agriculture in its main dimensions (enhancing production, being pro-poor, conserving resources and minimizing adverse effects on the environment). With the present state of knowledge, there persist significant uncertainties about the longer-term impacts and possible risks, primarily for human health (e.g. toxicity, allergenicity) or for the environment, e.g. fears of transmission of pest resistance to weeds, buildup of resistance of pests to the Bt toxins or the toxic effect of the latter on beneficial predators (see Chapter 11 for details). There is, therefore, a well-founded prima facie case for being prudent and cautious in the promotion and diffusion of these technologies.
However, the degree of caution any society will have about these products depends on societal preferences about their perceived risks and benefits. Certain segments of high-income societies with abundant food supplies (and occasional problems of unwanted surpluses) are unwilling to take any risks in order to have more and cheaper food, particularly when it comes to staples such as grains, roots and tubers. In contrast, poor societies with high levels of food insecurity can be expected to attach more weight to potential benefits and less to perceived risks. Obviously, the solution cannot be to let each society make its own choices, because the potential risks affect the global commons of environment, biodiversity and human health. All humanity has a stake in the relevant developments. Moreover, not all stakeholders are equally well informed about the pros and cons of the new technologies. In addition, the absence of a widely shared consensus risks segmenting the world food economy. It may raise obstacles to trade in products that may be acceptable to some countries and not to others.
Finding a solution calls for wide-ranging, well-informed, transparent and fully participatory debate. This is not an easy proposition, because the wealthiest and most risk-adverse societies (or significant segments of such societies) have a disproportionate command over scientific knowledge (including proprietary rights to the technologies) and over the media that can decisively influence the debate. If these distortions remain uncorrected, one cannot feel confident that the debate will lead to optimal results from the standpoint of world welfare. Hence the need for a stronger role of the public sector research system, particularly of the international one, in the generation and diffusion of technologies and related knowledge about the pros and cons.
Besides these possible retarding factors relating to the need for prudence and caution in the face of scientific uncertainties, there are other factors from the socio-economic and institutional spheres, often interacting with the former, that may act in the same direction. The principal among them have to do with the growing control by a small number of large firms of the availability and cost of inputs and technologies farmers will be using and of the use of scientific discoveries for the further development of technology. A whole array of issues pertaining to the establishment and enforcement of intellectual property rights (IPRs) and genetic use restriction technologies (GURTs) are relevant here (see Chapter 11).
Livestock production accounts globally for 40 percent of the gross value of agricultural production (and for more than half in developed countries). Developing countries will continue to increase their part in world production, with their share in meat going up to two-thirds of the world total by 2030 (from 53 percent in 1997/99) and in milk to 55 percent (from 39 percent). The past trend for the livestock sector to grow at a high rate (and faster than the crop sector) will continue, albeit in attenuated form, as some of the forces that made for rapid growth in the past (such as China's rapid growth) will weaken considerably (see discussion above).
The contribution of the increase in the number of animals will remain an important source of growth, but less so than in the past. In the meat sector, higher carcass weights will play a more important role in beef production and higher offtake rates (shorter production cycles) in pig and poultry meat production. The differences in yields (meat or milk output per animal) between developing and industrial countries are, and will likely remain, significant for bovine meat and milk, but much less so for pork and poultry, reflecting the greater ease of transfer and adoption of production techniques. However, factors making for a widening technology gap are also present and may become more important in the future. Among them, the most important is the development and progressive application of biotechnological innovations in the developed countries. The developing countries are not well suited to benefit; in the first place because they often lack the essential human, institutional and other infrastructure, and second because large private companies do not produce such innovations for small farmers in tropical countries.
The broad trends that are shaping the production side of the livestock sector evolution may be summarized as follows:
Policies to address all these issues are required if society is to benefit from the high-growth subsector of agriculture. For the developing countries, besides improved nutrition from higher consumption of animal proteins, the potential exists for livestock sector development to contribute to rural poverty alleviation. It is estimated that livestock ownership currently supports and sustains the livelihoods of 675 million rural poor. Benefits to the rural poor from the sector's growth potential are not, however, assured without policies to support their participation in the growth process. If anything, experience shows that the main beneficiaries of the sector tend to be a relatively small number of large producers in high-potential areas with good access to markets, processors and traders, and middle-class urban consumers. Desirable policy responses are discussed in Chapter 5, as are those relating to the all-important area of health (both animal and human) and food safety.
During the last two decades, pressures on diminishing forest resources have continued to grow. Traditionally, forestry outcomes were determined by demands for wood and non-wood forest products and the use of forest land for expansion of agriculture and settlements. However, in more recent years there has been a growing recognition of the importance of forestry in providing environmental goods and services such as protection of watersheds, conservation of biodiversity, recreation and its contribution to mitigating climate change. This trend is expected to persist and strengthen during the next 30 years, and increasingly the provision of public goods will gain primacy. In parallel, the expansion of forest plantations and technological progress will greatly help to match demand and supply for wood and wood products and contribute to containing pressures on the natural forest.
FAO's Forest Resources Assessment 2000 estimates the global forest area in 2000 at about 3870 million ha or about 30 percent of the land area. Tropical and subtropical forests comprise 48 percent of the world's forests, with the balance being in the temperate and boreal categories. Natural forests are estimated to constitute about 95 percent of global forests and plantation forests 5 percent. Developing countries account for 123 million ha (55 percent) of the world's forests, 1850 million ha of which are in tropical developing countries. During the 1990s, the net annual decline of the forest area worldwide was about 9.4 million ha, the sum of an annual forest clearance estimated at 14.6 million ha (a slight decline from that of the 1980s) and an annual forest area increase of 5.2 million ha. Nearly all forest loss is occurring in the tropics. Population growth coupled with agricultural expansion (especially in Africa and Asia) and agricultural development programmes (in Latin America and Asia) are major causes of forest cover changes.
In most developed countries, deforestation has been arrested and there is a net increase in forest cover. Such a situation is seen also in a number of developing countries, largely because of reduced dependence on land following the diversification of the economies. By 2030 most agriculture-related deforestation in Asia and to some extent also in Latin America could have ceased. In parallel, however, economic growth puts additional pressures on the forest by stimulating the demand for forest products, especially sawnwood, panel products and paper. Things may not move in that direction in Africa, where population growth, combined with limited changes in agricultural technologies and the absence of diversification, could result in continued forest clearance for agricultural expansion.
Current efforts towards wider adoption of sustainable forest management are expected to strengthen, although such efforts may not be uniform and are critically dependent on political and institutional changes. Inadequate investment in capacity building and persistent weaknesses of the political and institutional environment may limit the wider adoption of sustainable forest management in several countries, especially in sub-Saharan Africa.
Industrial wood demand is expected to grow, but this is estimated to be lower than in earlier forecasts. As noted, the area in forest plantations has been growing at a fast rate: it grew from 18 million ha in 1980 to 44 million ha in 1990 and to 187 million ha in 2000. Plantations are now a significant source of roundwood supply and they will become more so in the future. They could double output to some 800 million m3 by 2030, supplying about a third of all industrial roundwood. There will be substantial involvement of the private sector, including small farmers in the production of wood, also coming from«trees outside forests» (trees planted around farms, on boundaries, roadsides and embankments). The probable further growth of legally protected forest areas should be feasible without too much impact on future wood supplies. On the demand side, technological improvements in processing would help to reduce raw material requirements per unit of final product. Overall, the longer-term outlook for the demand-supply balance looks now much less problematic than in the past.
An estimated 55 percent of global wood production is used as fuelwood. Tropical countries account for more than 80 percent of global fuelwood consumption. Wood will continue to be the most important source of energy in the developing countries, especially for the poor in sub-Saharan Africa and most of South Asia. No significant changes in fuelwood consumption are likely over the period to 2015. Wood will remain a readily accessible source of fuel for millions of poor people throughout the world. Forests close to urban centres may continue to be subjected to heavy exploitation to meet the growing demand for charcoal. Notwithstanding localized shortages, demand will more or less be met, and demand for fuelwood may trigger planting in farmlands and other areas not used for agricultural purposes. The shift towards alternative fuels may accelerate beyond 2015, depending on changes in access to such fuels.
Improved access to manufactured products would reduce the dependence on several of the non-wood forest products traditionally used for subsistence consumption. There will however be an increased demand for certain items, especially medicinal and aromatic plants, ethnic foods and industrial products. While unsustainable exploitation from natural forests could result in a substantial decline in the supply of some of the valuable non-wood forest products, this may eventually lead to domestication and commercial cultivation of some of the more valuable ones. Although there will be significant improvements in the processing technologies, the producers of raw material are unlikely to be the main beneficiaries. This largely stems from persistent weakness in the research and development capacity of the producers.
During the next 30 years, one could witness an increase in the non-consumptive uses of forests, especially for protection of biodiversity, conservation of soil and water, mitigation of global climate change and recreational uses. In fact the cultural and uses of forests will gain prominence, although in many developing countries consumptive use of forest products will remain important. Environmental standards in forest resource management will be widely adopted. Although the expansion of protected areas may not be rapid, protection objectives will be growing in importance as determinants of forest land uses. Increasingly there are efforts to enhance the scope for action by the private sector, communities, non-governmental organizations (NGOs) and civil society at large. These latter changes, coupled with technological improvements, will bring about significant qualitative changes in forestry.
Fish remains a preferred food. Average world per capita consumption continued to increase to 16.3 kg in 1999, up from 13.4 kg in 1990. This development was heavily dominated by events in China. Excluding China, the apparent consumption per person in the rest of the world actually declined from 14.4 kg in 1990 to 13.1 kg in 1999. There are very wide intercountry differences. Reported per capita consumption ranges from less than 1 kg in some countries to over 100 kg in others. The global average per capita consumption could grow to 19-20 kg by 2030, raising total food use of fish to 150-160 million tonnes (97 million tonnes in 1999).
Marine capture fisheries have in the 1990s shown annual catches of between 80 and 85 million tonnes. Inland catches increased slowly to 8.3 million tonnes in 1999. While the gross volume of marine catches has fluctuated and does not show any definite trend, the species composition of the catch has changed, with high-value species (bottom-dwelling, or demersal species and large pelagics) gradually being substituted by shorter-lived surface dwelling (pelagic) and schooling fish.
By the end of the 1990s, an estimated 47 percent of major marine fish stocks were fully exploited, about 18 percent overfished, and another 9 percent depleted. Only a quarter of the fish stocks were moderately exploited or underexploited. The long-term yearly sustainable yield of marine capture fisheries is estimated at approximately 100 million tonnes. This assumes more efficient utilization of stocks, healthier ecosystems and better conservation of critical habitats. Increased landings also depend on improved selectivity of fishing gear, leading to less discarding of unwanted fish, and on sustained higher levels of catch from fisheries on restored stocks. However, this increase will be slow in materializing. Moreover, the estimated potential yield of capture fisheries (100 million tonnes) includes large quantities of currently minimally exploited living aquatic resources in the oceans, of which the most well known are krill, mesopelagic fish and oceanic squids.
The bulk of the increase in supply will therefore have to come from aquaculture. During the 1990s, aquaculture has shown a spectacular development (most of it in Asia, with China accounting for 68 percent of world aquaculture production), and by 1999 aquaculture accounted for 26 percent of world fish production (even 34 percent of fish food supplies). This growth could continue for some time, although constraints (lack of feeding stuffs, diseases, lack of suitable inland sites, environmental problems, etc.) are becoming more binding. Unless these constraints are relaxed, the long-term growth prospects of aquaculture, and hence of fish consumption, could be seriously impeded.
On the feed side, fishmeal producers expect that within a decade or so the aquaculture industry will use up to 75 to 80 percent of all fish oil produced, and about half of the available white fishmeal, while the prospects for growth in supplies are not encouraging. Although considerable research efforts have been undertaken, a satisfactory replacement for fish oil in aquaculture feed has still to be found. The proportion of fish reduced to fishmeal and oil (at present some 30 million tonnes) is likely to fall. In spite of an increasing demand for fishmeal following the intensification of livestock production and further expansion of aquaculture, an increasing share of small pelagic species (normally used for reduction) is likely to be used for food. The fishmeal industry will therefore be forced to find other sources, the most likely of which is zooplankton (initially Antarctic krill).
The single most important influence on the future of wild capture fishery is one of governance. Although in theory renewable, wild fishery resources are in practice finite for production purposes. They can only be exploited so much in a given period; if overexploited, production declines and may even collapse. Hence total fishery production from the wild cannot increase indefinitely. Resources must be harvested at sustainable levels, and access must be equitably shared among producers. So far only very few managers have succeeded in creating sustainable fisheries. As fish resources grow increasingly scarce, conflicts over allocation and sharing are becoming more frequent.
The principal policy challenge is to establish rules for access to fish stocks. Fisheries based on explicit and well-defined rights of access will need to become more common; when rights are well defined, understood and observed, allocation conflicts tend to be minimized. These issues are the subject of an increasing body of international and bilateral agreements dealing with legal access rights.
Another major policy challenge is to bring the global fishing fleet capacity back to a level at which global fish stocks can be harvested sustainably and economically. Past policies have promoted the buildup of excess capacity in the fishing fleet and incited fish farmers to increase the catch beyond sustainable levels. Policies have to react fast to unwind the overcapacity that has been built up over the past to ensure a return to a steady-state fish stock. This process is already under way and has, among other things, led to a contraction of the capture fisheries labour force in developed countries.
A third important policy consideration is the increasing pressure from various quarters in society to reduce environmental damage associated with both capture and culture fisheries. This has also led to a set of national and international rules and laws, some voluntary in nature, regulating fishery methods.
A major factor, affecting both the sustainability of capture fisheries and the expansion of aquaculture, will be the expected improvements in the understanding of the marine ecosystem. Improved knowledge will encompass the working of ecosystems, including the dynamics of fish stocks, and the effects of human intervention on such ecosystems. This knowledge would increase fisheries productivity, facilitate improved fisheries management and enable monitoring of fisheries operations, to ensure compliance with rules and regulations and to assess their impact on the environment.
The quantum gains in agricultural production and productivity achieved in the past were accompanied by adverse effects on the resource base of agriculture that put in jeopardy its productive potential for the future. Among these effects are, for example, land degradation; salinization of irrigated areas; overextraction of underground water; growing susceptibility to disease and buildup of pest resistance favoured by the spread of monocultures and the use of pesticides; erosion of the genetic resource base when modern varieties displace traditional ones and the knowledge that goes with their use. Agriculture also generated adverse effects on the wider environment, e.g. deforestation, loss or disturbance of habitat and biodiversity, emissions of greenhouse gases (GHGs) and ammonia, leaching of nitrates into waterbodies (pollution, eutrophication), off-site deposition of soil erosion sediment and enhanced risks of flooding following conversions of wetlands to cropping.
The production increases in prospect at the world level for the period to 2030 (in terms of the absolute quantities involved) will be of an order of magnitude similar to those that took place in the comparable historical period (e.g. for cereals and sugar) or even higher (e.g. for meat and vegetable oils). Thus, almost another billion tonnes of cereals must be produced annually by 2030, another 160 million tonnes of meat, and so on. It follows that pressures on the resources and the environment will continue to mount. The challenge facing humanity is how to produce the quantum increases of food in sustainable ways (preserving the productive potential of the resource) while keeping adverse effects on the wider environment within acceptable limits. A priori, the task looks more difficult than in the past because:
The preceding considerations and the magnitudes involved suggest that the increases in production and associated progress in food security cannot be achieved at zero environmental cost. The issue is whether any threats to the resource base of agriculture and the generation of other environmental«bads» associated with more production and consumption can be contained within limits that do not threaten sustainability, that is the ability of future generations to have acceptable food security levels within acceptable more general living standards, including a clean environment. Often the choices present themselves in the form of what are acceptable trade-offs, rather than whether we can have something for nothing. There are trade-offs over time, among the different dimensions of sustainability and over space (e.g. among countries or regions within countries).
An example of trade-offs over time is the eventuality that deforestation (including more general disruption of wildlife habitats) of the past as well as the one now taking place could be reversed in the future when the pressures for further increases in output will be eased and the advancement of yields could lead to less land being needed for any given level of output. Europe's experience seems to point in this direction.
Trade-offs between different dimensions of sustainability include, for example, the higher herbicide applications that could accompany efforts to increase water use efficiency and/or reduce methane emissions by shifting rice cultivation from flooded and transplant to direct seeding. Similarly, the shift to no-till/conservation agriculture in order to reduce soil erosion risks and increase the carbon sequestration capacity of soils (see below), favours the development of weeds that may provoke increased use of herbicides. In like manner, combating the effects of saltwater intrusions into irrigation aquifers in coastal areas (because of overextraction or sea level rise) may require the acceptance of genetically modified salt-tolerant crops together with some as yet unknown risks. In livestock, the shift from ruminant meat to pork and poultry may slow down the growth of methane emissions from ruminant livestock but will aggravate the problem of livestock effluent pollution from large pig and poultry industrial units. Similarly, grazing restraints on extensive rangelands have their counterpart in the increase of feedlot-raised cattle with, as a result, enhanced point source pollution as well as eventual effects on arable land elsewhere, including in other countries, generated in the process of producing more cereals for the feedlots.
Trade-offs among countries relate primarily to the potential offered by international agricultural trade to spread across the globe the environmental pressures from increased production. The individual countries differ as to their capabilities to withstand adverse effects associated with increasing production because they differ in the relative abundance of their resource endowments; they possess agro-ecological attributes that make their resources more or less resilient; or they are at present more or less stretched from past accumulation of environmental damages. Countries also differ as to their technological and policy prowess for finding solutions and responding to emerging problems.
Trade can contribute to minimizing adverse effects on the global system if it spreads pressures in accordance with the capabilities of the different countries to withstand and/or respond to them. Whether it will do so depends largely on how well prices in each country reflect its«environmental comparative advantage». This requires that, in addition to absence of policy distortions that affect trade, the environmental«bads» generated by production be embodied in the costs and prices of the traded products, which is not normally the case when externalities are involved. If all countries meet these conditions, then trade will contribute to minimizing the environmental«bads» globally as they are perceived and valued by the different societies, although not necessarily in terms of some objective physical measure. This latter qualification is important because different countries can and do attach widely differing values to the environmental resources relative to the values of other things, such as export earnings and employment. In the end, the values of environmental resources relative to those of other things are anthropocentric concepts and countries at different levels of development and with differing resource endowments are bound to have differing priorities and relative valuations.
An additional mechanism through which trade can contribute to spread pressures across the globe in ways that minimize adverse effects on sustainability has to do with the enhanced degree of product substitutability afforded by trade, e.g. substituting imported palm oil for locally produced oil from sunflower seed or soybeans. Producing a tonne of palm oil in East Asia requires only a fraction of the agrochemicals (fertilizer and pesticides) used to produce a tonne of oil from sunflower seed or soybeans in Europe, for example.
In considering the prospects for the future, we must be aware that history need not repeat itself as concerns the extent to which the continued growth of production will be associated with adverse effects. The projections to 2030 suggest that some effects will be different from those of the past simply because their determinants will be changing, e.g. the lower growth of rural population will tend to slow down the rate of deforestation. Others will be different because of policy changes; for example, the EU, having paid the environmental cost of transforming itself from a large net importer of sugar to a large net exporter, now has policies that do not favour further expansion of exports. Finally, history need not repeat itself because of the wider adoption of more environmentally benign technologies and of policies that favour them and/or remove incentives for unsustainable practices, e.g. for expansion of ranching into forested areas. Approaches to agricultural production that offer scope for minimizing adverse impacts include those described in the following paragraphs.
Integrated pest management (IPM) promotes biological, cultural, physical and, only when essential, chemical pest management techniques. Naturally occurring biological control is encouraged, for example through the use of alternate plant species or varieties that resist pests, as is the adoption of land management, fertilization and irrigation practices that reduce pest problems. If pesticides are to be used, those with the lowest toxicity to humans and non-target organisms should be the primary option. Precise timing and application of any pesticides used are essential. Broad-spectrum pesticides are only used as a last resort when careful monitoring indicates they are needed according to pre-established guidelines. Given that chemical pesticides will continue to be used, the need for rigorous testing procedures before they are released on to the market (as well as sharing of the relevant information among countries) cannot be overemphasized. The same applies for the need to have comprehensive and precise monitoring systems to give early warning of residue buildup along the food chain, in soils and in water.
Integrated plant nutrient systems (IPNS). The depletion of nutrient stocks in the soil (nutrient mining), which is occurring in many developing countries, is a major but often hidden form of land degradation, making agricultural production unsustainable. In parallel, overuse or inappropriate use of fertilizers creates problems of pollution. IPNS hold promise of mitigating such adverse effects by recycling all plant nutrient sources within the farm and use of nitrogen fixation by legumes to the extent possible, complemented by the use of external plant nutrient input, including manufactured fertilizers.
No-till/conservation agriculture (NT/CA) involves planting and maintaining plants through a permanent cover of live or dead plant material, without ploughing. Different crops are planted over several seasons, to avoid the buildup of pests and diseases and to optimize use of nutrients. NT/CA has positive effects on the physical, chemical and biological status of soils. Benefits include reduced soil erosion, reduced loss of plant nutrients, increase in organic matter levels of soils, higher rainfall infiltration and soil moisture holding capacity and, of course, savings in fossil fuel used in soil preparation.
Organic agriculture. Although the growing demand for organic foods is to a large extent driven by health and food quality concerns, organic agriculture is above all a set of practices intended to make food production and processing respectful of the environment. It is not a product claim that organic food is healthier or safer than that produced by conventional agriculture. Organic agriculture is essentially a production management system aiming at the promotion and enhancement of ecosystem health, including biological cycles and soil biological activity. It is based on minimizing the use of external inputs, representing a deliberate attempt to make the best use of local natural resources. Synthetic pesticides, mineral fertilizers, synthetic preservatives, pharmaceuticals, GMOs, sewage sludge and irradiation are prohibited in all organic standards. Naturally, this by itself does not guarantee the absence of resource and environmental problems characteristic of conventional agriculture. Soil mining and erosion, for example, can also be problems in organic agriculture.
In conclusion, future agro-environment impacts will be shaped primarily by two countervailing forces: mounting pressures because of the continuing increase in demand for food and agricultural products mainly on account of population and income growth; and decreasing pressures via technological change, institutional and policy responses to environmental degradation caused by agriculture, and structural change in the sector. On balance, the potential exists for putting agriculture on a more sustainable pathway than a continuation of past trends would indicate. The main requirement is increasingly to decouple agricultural intensification from environmental degradation through the greater exploitation of biological and ecological approaches to nutrient recycling, pest management and soil erosion control.
Climate change: agriculture's role in climate change. Agricultural activities contribute to climate change through the emission of GHGs. They also contribute to climate change mitigation through carbon sequestration in cropland and the provision of biofuels that can substitute for fossil fuels. Globally, they generate some 30 percent of total anthropogenic emissions of GHGs. The main ones are carbon dioxide (CO2 - agriculture accounts for about 15 percent of total anthropogenic emissions); methane (CH4 - about 50 percent coming from agriculture); and nitrous oxide (N2O - agriculture accounting for about two-thirds). Both CH4 and N2O are gases with warming potentials many times higher than that of CO2. The main source of CO2 emissions is tropical forest clearance, related biomass burning and land use change. For methane the chief sources are rice production and livestock through enteric fermentation of ruminants and animal excreta. For nitrous oxide it is mineral fertilizer and animal wastes - manure and deposition by grazing animals.
Future emissions from agriculture will be determined by the evolution of the main variables (land use, fertilizers and numbers of animals) and their qualitative changes, as presented in the preceding sections and discussed in more detail in individual chapters. Thus, carbon dioxide emissions could be stable or even less than in the past because of slower deforestation and land cover change. Likewise, methane emissions from rice cultivation will slow down or possibly even decrease (through changes in paddy field flooding and rice varieties), but annual methane emissions from livestock could increase by 60 percent by 2030. Also, growth of nitrous oxide emissions from fertilizers will be slow (slow growth in consumption combined with a more efficient use of fertilizers) but, as for methane, emissions from livestock (animal waste) could increase by some 50 percent by 2030.
Agricultural land sequesters carbon in the form of vegetation and soil organic matter (SOM) derived from crop residues and manure. The potential exists for it to sequester much more carbon than it actually does under most current cropping practices. This potential is assuming growing economic, political and environmental importance in the context of the Kyoto Protocol. The crop production projections of this study imply an increase in total biomass production and unharvested residues, hence an increase in gross carbon sequestration. Cropland can be made to increase carbon sequestration if managed for this purpose. The above-mentioned no-till/conservation agriculture is a major approach to increasing carbon in the soil, and it also contributes to lower GHG emissions through the reduced use of fuel. Better residue management and changes in cropping patterns can also contribute to carbon sequestration. Even greater gains per hectare could be achieved where marginal cultivated land is taken out of crop production and replaced by grass or legume forages. Permanent set-aside of agricultural land would sequester large amounts of carbon if forested or left to revert to tree scrub. Finally, degraded land that has gone out of production, e.g. saline soils, could be restored to sequester carbon.
In conclusion, managing agricultural land to sequester more carbon could transform it from a net source to a net sink. The rate of sequestration gradually declines before reaching a limit and can be especially high during the first few years. Some of the carbon sequestration will not be permanent and eventually the gains will level off. This notwithstanding, managing agricultural land for carbon sequestration will extend the time available to introduce other measures with longer-term benefits.
Climate change: impacts on agriculture. The main parameters of climate change with potential effects on agriculture and food security are as follows:
Recent research has suggested that some impacts of climate change are occurring more rapidly than previously anticipated. For example, average sea temperatures in northern latitudes are rising rapidly (in particular in the North Sea), ocean currents are being disrupted and phytoplankton populations altered.
The main effects of these changes on food and agriculture are foreseen to be the following:
The main impacts of climate change on global food production capacity are not projected to occur until after 2030, but thereafter they could become increasingly serious. Up to 2030 the impact may be broadly positive or neutral at the global level. However the regional impacts will be very uneven. Food production in higher latitudes will generally benefit from climate change, whereas it may suffer in large areas of the tropics. Over the period to 2030, the most serious and widespread agricultural and food security problems related to climate change are likely to arise from the impact on climate variability, and not from progressive climate change, although the latter will be important where it compounds existing agroclimatic constraints.
Naturally, the prospect that global production potential may not be much affected by climate change, or may even rise, is poor consolation to poor and food-insecure populations with high dependence on local agriculture and whose agricultural resources are negatively affected. Even small declines in the quantity and quality of their agricultural resources can have serious negative impacts on livelihoods and food security. Among the obvious responses to these emerging risks are accelerated economic growth and diversification of economies away from heavy dependence on vulnerable agricultural resources, and promotion of technologies and farming practices to facilitate adaptation to changing agro-ecological conditions.