Feed the soil to feed the people
Fertilizer has been a faintly unfashionable topic in recent years. But, like many other fashions, it has returned to favour as the world has finally woken up to the fact that without fertilizers we have no hope of feeding the soil. Unless we feed the soil, what hope have we of feeding people?
The global population is still growing and might, if we are lucky, reach a plateau of eight to ten billion in some thirty years from now. More people means that we need more food. We also see that natural resources, i.e. land, water and energy, are becoming scarce and thus expensive, especially in the overpopulated regions of Asia. Population pressure, together with restricted availability of resources, will consequently create demands for increasing productivity from those resources that are currently being used.
Secondly, it is not only the increasing number of people who ask for more, and affordable, food, it is also changing food habits that are presenting a challenge to world agriculture. Driven by an advancing urbanization, especially in developing countries, people look for more diverse and easily manageable food. This has its impact on the crop spectrum because the increasing demand for animal protein will also stimulate the production of feed grains, particularly maize and soybean.
Thirdly, the demand for more and diverse food is increasingly complemented by the demand for high quality and safe food produced in a clean and healthy environment. Recent food crises in Europe question the trustworthiness of conventional agriculture. Many consumers and politicians see an alternative in organic agriculture. But can farming based on recycling with restricted external inputs be sustainable? And can low-input agriculture produce enough food at affordable prices?
We need food security, food diversity, food quality and food safety from farming systems which comply with the needs of the environment, which safeguard natural resources and which should be sustainable at the same time. One of the key elements to achieve this goal is appropriate fertilizer use and nutrient management because without plant nutrients, plants cannot produce.
However, fertilizers must be used more efficiently than is current practice in many parts of the world. It is a question of balance. If nitrogen (which is the most widely used nutrient because it is cheapest and shows most immediate crop response) is applied at an unbalanced rate in comparison with other nutrients, it will not only be a loss to the farmer's pocket, it will pose a risk to the environment. And the nutrient that is most often neglected? Potassium. And we should not forget that plants take up potassium in the same quantity, or even more than, nitrogen.
The current use of potash, especially in developing countries, is far below the removal of potassium by harvested crops. The effect is to mine the soil of its stock. Notoriously difficult to ascertain directly, nevertheless the effect of potassium deficiency is becoming evident in stagnating yields, increased susceptibility to pests and diseases and lowered resistance to the stresses of drought, cold, heat and salinity. Potassium is absolutely vital to plant health and yet farmers in developing countries remain by and large indifferent to it. One reason is cost. Production of potash is limited to a relatively few sites in the world and so most countries must import it. All fertilizer prices depend on infrastructure, transport facilities and market demand. Farmers in Africa, for example, may have to pay up to six times the price that farmers in other, more affluent parts of the world, pay.
Consumers, especially those in the developed world, must not be deceived into thinking that affordable food for all can be produced on soils that are constantly being deprived of nutrients. The balanced use of fertilizers brings benefits to farmers, to consumers, to rural development and to the wider economy. Above all, it helps to protect the environment because it makes agriculture more sustainable with better, more productive use of those natural resources upon which the food security of the world depends.
* The International Potash Institute (IPI), is a service of the European and Near East potash industry and acts as a link between farmers, scientists, policy makers and the industry.
1st July 2003