Land area for agricultural use is shrinking on a per capita basis. Inflation is eroding the farmer's purchasing power. At the same time, there is a lack of current, unbiased scientific data to encourage the proper use of purchased inputs such as mineral fertilizers. Soil analysis services are insufficient to permit extension agents and distributors to give sound technical advice. These guidelines can be useful in contributing to the development of agricultural systems that are environmentally and economically sustainable.
Ecological preservation is possible only under favorable economic conditions for the farmer.
The accepted principles of crop fertilization covered in these guidelines can be applied in a general way for all fertilizer sources, mineral and organic. Specific scientific data should be the basis for the guides so that balanced fertilization can be practiced. Objectives of the Guidelines To explain how mineral fertilizers should be used to supplement existing soil fertility levels in meeting plant nutrient requirements. To restore and maintain soil fertility levels for long-term soil productivity by proper use of mineral fertilizers. To show how nutrient losses, both by erosion and to groundwater, can be minimized with sound fertilizer management.