Monoculture farming part I: Deforestation and the use of fertilizers

Today’s post will kick start the 1st theme of the entire blog- Monoculture commercial farming.

What is monoculture?

Monocultures are large areas of land cultivated with a single crop, which can include both food-base agriculture and plantation farming. Monoculture farming is the most common form of commercial farming in the world.

A major problem associated with monoculture is that land that has been devoted to agriculture for a single species will suffer a great diminish of soil fertility. The rain-forest soil in which they are originally planted is particularly rich in nutrients. However, deforestation to make way for monoculture plantations has resulted in the loss of a great amount of productive land. The transition to agriculture from natural vegetation often cannot hold onto the soil and many of these plants, such as bananas, coffee, cotton, and wheat, can actually increase soil erosion beyond the soil’s ability to maintain itself (WWF).

Since only a minority of areas have good soils, which after clearing are eroded by the heavy rains during the window period (between post deforestation and maturing of crop yields), soil fertility decline and farmers will either intensify their use of fertilizers or clear additional forest.

Erosion can be extremely costly for developing countries. For example, Costa Rica loses about 860 million tons of valuable topsoil every year, while Madagascar, loses almost 400 tons/ ha annually. In the late 1980s, Java, Indonesia was losing 770 million metric tons of topsoil every year at an estimated cost of 1.5 million tons of rice, enough to fulfill the needs of 11.5-15 million people.

Aforementioned, producers tend to either clear more forests or intensify the use of fertilizers. For the former, the expansion of the fields to make up for the diminished production per hectare causes the cycle of destruction again, resulting in a positive feedback system in environmental pollution, accentuating its impacts.

For the latter, the intensifying use of fertilizers was associated with a 6.87-fold increase in nitrogen fertilization and a 3.48-fold increase in phosphorus fertilization. Coupled with the need to increase more food supply to meet the demands of the rising population, the anticipated doubling of global food production would be associated with approximately 3-fold increases in nitrogen and phosphorus fertilization rates.

These projected changes can have drastic impacts on the diversity, composition, and functioning of the remaining natural ecosystems, and their ability to provide society with a variety of essential ecosystem services. The largest impacts would be on freshwater and marine ecosystems, which would be greatly eutrophied by high rates of nitrogen and phosphorus release from agricultural fields.

Aquatic nutrient eutrophication can lead to loss of biodiversity, outbreaks of nuisance species, shifts in the structure of food chains, and impairment of fisheries. These are possible because the algae blooms, associated with eutrophication, can cause anoxia/ hypoxia, a condition in which the dissolved oxygen content in the water is diminished. This makes it difficult to maintain the aquatic biodiversity at status quo. Moreover, oxygen demanding wastes, such as food waste, dead plant and animal tissue that consumes oxygen dissolved in water during its degradation, can deplete the already limited dissolved oxygen required for survival of aquatic organism.

The bloom covers an area over 8,500 square miles

Massive Phytoplankton bloom a.k.a algae bloom in the Gulf of Mexico due to fertilizer run off from the Mississippi River

Eutrophication is also a source of carbon dioxide emission. When the aquatic organisms die from anoxia/ hypoxia, they decompose due to bacterial and fungi activity; and in the process oxygen is consumed and nutrients are released together with carbon dioxide and energy. This rise in carbon dioxide emission will in turn cause ocean acidification when the eutrophied water sources flows into the oceans.

It is evident that environmental pollution caused monoculture commercial farming is multi-faceted, where environmental pollution can occur at any stage of the farming (deforestation, use of fertilisers, harvesting and fallow periods), and can have impacts across the 4 spheres of the Earth.

That will be all for today, and stay tune 😀

The next post will be on focused on the environmental pollution caused by banana commercial farming, and its accompanying health effects.


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