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Environmental Effects of Chemical Fertilizers

fertile farmland valley image by Yali Shi from

A chemical fertilizer is a fertilizer comprising chemically refined or otherwise processed compounds. Manufacturers create chemical fertilizers from inorganic materials, with the goal being to replicate (and increase the potency of) natural, organic nutrients. Many environmentalists are against the use of chemical fertilizers, as they can produce several negative environmental effects.

Infertile Soil

The synthesized materials manufacturers use in their chemical fertilizers may help plants grow, but they do not help the soil they grow in. In fact, they can do quite the opposite. According to Garden Counselor Lawn Care, the unnaturally high levels of nutrients that some chemical fertilizers contain can oversaturate soil and cancel out the effectiveness of other vital nutrients.

Acidic Soil

Another way chemical fertilizers can make soil infertile is by increasing its acidity. Many chemical fertilizers contain sulfuric and hydrochloric acid, which if used in excess can cause serious harm to microorganisms (specifically the type that helps supply plants with nitrogen). This can have a serious impact on the soil’s pH and adversely affect plant growth.

Increased Microorganisms

Nitrogen-rich chemical fertilizers can have the complete opposite effect on soil in comparison to more acidic fertilizers. Too much nitrogen can lead to a microorganism population boom. In large enough numbers, these microorganisms, instead of helping plants, will hurt them, as they will consume all of the organic material and nutrients in the surrounding soil.

Groundwater Pollution

Plants can only absorb a certain amount of nutrients. So if you over apply a chemical fertilizer, not all of the chemically synthesized nutrients within it will actually contribute to the plant’s health and growth. Instead, the unused fertilizer will seep into the ground, where it can be carried by rain and irrigation ditches into streams, rivers, lakes, reservoirs and oceans. The chemical compounds in the fertilizer can contaminate drinking water supplies and disrupt ecosystems.

Salt Burns

Chemical fertilizers are often very salty. The over-application of chemical fertilizers can thus contribute to plants developing unsightly “salt burns.” These occur when an over saturation of salt leads to certain areas of the plant becoming dehydrated, and plant tissues dry out.

Excess Growth

Due to the high potency of chemical fertilizers, they can sometimes lead to plants becoming too big for their own health. Larger limbs and thicker foliage translates to a considerable increase weight, which can put stress on a plant’s roots.

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