World agriculture towards 2030/2050: the 2012 revision - Fao

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Daberkow et al. (2000) state that increased use of fertilizer is becoming even more
crucial in view of other factors, such as the impact on soil fertility of more intensive
cultivation practices and the shortening of fallow periods. There is empirical evidence that
nutrient budgets 83 change over time and that higher yields can be achieved through reduction
of nutrient losses within cropping systems. That is, increases in food production can be
obtained with a less than proportional increase in fertilizer nutrient use. Frink et al. (1998)
showed this situation for maize in North America. Farmers achieve such increased nutrient
use efficiency by adopting improved and more precise management practices. Socolow
(1998) suggests that management techniques such as precision agriculture offer abundant
opportunities to substitute information for fertilizer. It is expected that this trend of increasing
efficiency of nutrient use through better nutrient management, by improving the efficiency of
nutrient balances and the timing and placement of fertilizers, will continue and accelerate in
the future.
Projections for fertilizer consumption have been derived applying non-linear (piecemeal
linear) relationships between yields and fertilizer application rates (separately for N, P and K
fertilizer) for 34 crops grown under rainfed and irrigated conditions. Country-specific data
from FAOSTAT for the base year 2005/07 on N, P and K consumption and for harvested land
and yield by crop were used to calibrate (scale) the functions (for 105 countries and country
groups 84 ) to reproduce the 2005/07 fertilizer consumption in each country (see Bruinsma et
al., 1983, for a description of the methodology).
The overall result, aggregated over all crops and countries, is that fertilizer consumption
could increase from 166 million tonnes in 2005/07 to 263 million tonnes in 2050 (see Figure
4.12 and Table 4.15). This would imply a continuing slowdown in the overall growth of
fertilizer consumption (Table 4.15) with particularly slow growth in the developed countries
and East Asia. The reasons for this will be explained below 85 .
The developing countries account at present for almost 70 percent of world fertilizer
consumption and this share could increase further to over three-quarters of world
consumption in 2050. China and India alone account for almost two-thirds of the developing
countries’ fertilizer consumption but this could decline to about half the consumption in 2050
as other regions will catch up. The decline in world fertilizer consumption in the 1990s
(Figure 4.12) was mainly caused by the decline in the transition countries following systemic
reforms. Growth in fertilizer use in the industrial countries, especially in Western Europe, is
expected to lag significantly behind growth in other regions of the world. The maturing of
fertilizer markets during the 1980s in North America and Western Europe, two of the major
fertilizer consuming regions of the world, account for much of the projected slowdown in
fertilizer consumption growth. In the more recent past, changes in agricultural policies, in
particular reductions in support measures, contributed to a slowdown or even decline in
fertilizer use in this group of countries. Increasing awareness of and concern about the
environmental impacts of fertilizer use are also likely to hold back future growth in fertilizer
use.
83 A nutrient budget is defined as the balance of nutrient inputs such as mineral fertilizers, manure, deposition,
biological nitrogen fixation and sedimentation, and nutrient outputs (crops harvested, crop residues, leaching,
gaseous losses and erosion).
84 See Appendix 1 for a list of the countries and crops included.
85 Earlier fertilizer projections made in 2001-02 (Bruinsma, 2003, pp. 148-151) considerably underestimated
developments in world fertilizer consumption, projecting a consumption of 165 million tonnes by 2015, a level
which in practice had already been reached by 2005/07.
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