Where we are
The planet’s land area is finite. Furthermore, the proportion of the land that is endowed with sufficient water and favourable soil resources to sustain essential ecosystem functions, and meet the demands of agriculture to produce food, animal feed and energy necessary to support human health and enterprise, is narrowly constrained. Finding a balance that accommodates these competing demands for productive land that is equitable across all geographic regions and economic sectors is one of the major challenges of this century.
More people means more food
Agriculture feeds a growing global population. Between 1985 and 2005, agricultural land (cropland and pasture) increased by only about 3 %. In contrast, agricultural production increased by about 28 %, largely as a result of increased efficiency. Yet, about a billion people remain chronically malnourished. There are striking global patterns in crop production. Some regions are largely devoted to food production; others are involved in non-food crops. The same general patterns recur in many categories of agricultural statistics, as shown in the accompanying map of the proportion of land used for food production. In North America and Europe, only 40 % of the land area is dedicated to food crops, while in Africa and Asia, about 80 % of the arable land is used for food crops. These distinctions are reflected in the global distribution of large field sizes, major industrialised crops, the intensity of fertiliser use and water used for crop irrigation.
Industrialised agriculture involves varying degrees of landuse intensity. As the pressure of use increases, there is a corresponding increase in pressure on the ecological services provided. This is not only on available land, but also on the diversion of water resources and the large-scale application of fertilisers and pesticides. Conversely, there are vast agricultural areas where smallholders do not have access to irrigation or fertilisers. Smallholders in Africa and Asia are heavily engaged in production of food crops. However, they have poor access to technology (e.g. irrigation pumps, supplemental fertilisers, machinery) and relevant knowledge. As a consequence, they suffer the highest levels of malnourishment. Yet, because their primary objective is food production for subsistence, the rural poor are often forced to overexploit land resources through low-input and low-yield agriculture, deforestation and overgrazing. Thus, with respect to agricultural inputs, land degradation can result from both too much and too little access to resources.
Changing diets mean new demands.
As the world’s economy grows – however unevenly – there is a corresponding increase in the demand for meat and other animal products. This occurs in developing countries where diets are changing as a function of rising incomes, continuing urbanisation and changing food preferences. Over the past 50 years, increased demand for animal products accounts for 65 % of agricultural land-use change.
As a result of increasing urbanisation, global livestock production has been shifting from rural to urban areas, to get closer to consumers, sources of feed transport and trade hubs. The increasing use of feedlots for livestock to meet the demands for meat and dairy products increases the need to produce animal feed on extensive areas of cropland. Even efficient use of productive cropland for animal feed is a potential reduction of the global food supply.
Does more biofuel mean less food?
Concern over rising levels of carbon dioxide in the atmosphere has led government mandates in North America and Europe designed to offset some proportion of fossil fuel demand with fuels produced from biomass. These have been met by ethanol produced from crops, largely maize and sugarcane. The diversion of significant portions of crop production from food or animal feed into biofuel production has been contentious because of its effect on global food prices, particularly as India and China develop similar mandates for ethanol use. Using high-yielding tropical croplands to produce sugarcane, oil palm and soybean for biofuels contributes little to the global calorie or protein supply. However, in some instances it does provide a source of income to help alleviate local poverty. It is expected that effects of biofuels on food prices may decline somewhat in the future with the development of “second generation” biofuels derived from agricultural waste products rather than the crops themselves. However, this new demand places yet another pressure on limited agricultural lands beyond food and feed production that, ultimately, could threaten long-term sustainability.