Following are some of the harmful affects of chemical fertilisers:
1. It causes ground water pollution by the process of leaching.
2. The chemicals react with clay to create hard layers of soil known as hardpan.
3. Soil crumbs are affected by the chemicals in the soil and as a result the soil is left with less drainage and less air circulation.
4. Causes soil acidification.
5. According to a research conducted by the U. S. Department of Agriculture Nutrient Data Laboratory, food grown in soils that were chemically fertilized were found to have less magnesium, potassium and calcium content.

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