The effects of fertilizers and minerals on environment and on plants

Introduction

Plants need at least 16 essential nutrients to accomplish their growth cycle. These elements are carbon, oxygen, hydrogen, nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, iron, manganese, zinc, copper, boron, molybdenum and chlorine.

Plants use nitrogen (N), phosphorus (P) and potassium (K) in large quantities, and thus the soil reserves of these nutrients must be replenished periodically to maintain a good productivity. Synthetic fertilizers have been developed to provide three major elements. Other fertilizers were developed to provide the other 13 nutrients, if necessary. (Crosson, p.125)

A fertilizer is an inorganic or organic that is made to provide sufficient quantities of one or more essential elements for plants. Recent concerns about the effects of fertilizer on the environment, the low efficiency of fertilizers, high prices and low prices for agricultural products have made urgent the development of a rational approach for choosing the fertilizer to use. In this newsletter we will focus on fertilizers containing the three elements N, P and K.

The effects of fertilizer on the environment

The use of fertilizers to increase crop yields has recently been the subject of environmental concerns. Among the negative effects attributed to fertilizer include:

- They pollute the soil with toxic heavy metals such as cadmium;

- They pollute the groundwater, affecting the drinking water and increased health hazards;

- They pollute rivers and coastal waters, which can cause eutrophication and affect the lives of fish and other aquatic life (Castle, p.100)

- They pollute the atmosphere through denitrification and volatilization of ammonia and thus contribute to global warming of the earth.

The negative effects of fertilizer are the result of their misuse, rather than intrinsic properties of these products. Currently, these problems arise mainly in industrialized countries with high use of fertilizers.

In Morocco, the level of fertilizer use is still low, with nearly 330,000 tons of nutrients per year, an average intake of 45 kg / ha. Although the average doses are low, using these fertilizers in some areas, especially in irrigated areas are excessive. To continue to benefit from improved crop productivity that allows the use of fertilizers without damaging the quality of the environment, it is necessary to adopt a code of good agricultural practices that will be based on:

- Soil testing: performed before the installation of the culture, it can determine its nutrient needs. Since currently the majority of farmers do not or cannot do soil testing, another ...