Negative Impacts of Agriculture on the Environment Due to Large Urban Population

The Environment Pays Greatly For Us To Eat.

Photo 1[1]

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Fires intentionally set to land? Who would do such as thing? Why would they? These are some questions I ask myself when thinking of slash and burn agriculture. As seen from photo 1 above slash and burn agriculture involves intentionally setting fire to a piece of land in order to clear it of existing vegetation for agricultural purposes. It surely has many deleterious effects on the environment, air pollution clearly as there is so much smoke produced, habitat loss for animals as their home is destroyed and aesthetic displeasure as the land is left bare and scorched. Shouldn't it be clear that this practice is largely degrading to the environment and as such not be practiced? Apparently not as this is one of many improper, unsustainable practices used in contemporary society for agriculture. 

Due to the ever growing population of Trinidad and Tobago, food production is essential to sustain the lives of its people and ensure there is food security. In Childe 1950 it was stated that due to the introduction of irrigation cultivation, the social "surplus" were large enough to support a number of resident specialist who had been released from food production. This led to the formation of the first cities "units of settlements ten times greater than any neolithic village". What can be taken from this is that due to the increase in "surplus" of food production, the carrying capacity of the land increase and as such more and more people inhabited the area, forming what was known as cities. This is similar to contemporary society where because of the large population in urban areas, there are lands specified for agricultural purposes to grow food to feed the population. This large demand leads to intensified agricultural practices to meet said needs.

Agriculture plays many important roles for Caribbean countries such as Trinidad and Tobago, most notably are its contributions to foreign exchange, GDP & GNP, food security and employment. Hoever agriculture involves many practices which can lead to deleterious effects on the environment such as deforestation, coastal degradation, water shed degradation, soil degradation, flooding and reduction in biodiversity. The impacts of improper agricultural practices on the environment are described below:

Forests are vital for life as they provide a habitat for animals, protect soil from erosion, create oxygen and store carbon dioxide which helps to control climate . According to United Nations Development Programme (UNDP (2010) unsustainable acts of agriculture include the major use of slash and burn (as seen in photo 1) in order to prepare lands for planting. This leads to high levels of deforestation, as seen in the case of Trinidad according to Environmental Management Agency (EMA 2001), there was a net loss of 11.6% of forested area from 1990 to 1998. This is as a result of fires going uncontrolled which according to the UNDP also resulted in protected areas such as El Tuchuche being destroyed after lower hillside areas were ignited for the purpose of preparing land via the slash and burn method by farmers. These forests once destroyed are not able to return to their original state as secondary growth takes place. Slash and burn agriculture also leads to habitat destruction for animals as well as food sources are lost and animals are killed in the process resulting in reduction of biodiversity (UNDP 2010). 

Further negative results of deforestation include water degradation, river and coastal degradation. In a national report done by the Water Resources Agency (WRA 2001) agricultural practices was stated as a major threat to wetlands in Trinidad. These practices included deforestation via slash and burn agriculture and excessive use of pesticides, insecticides and synthetic fertilizers. After slash and burn is performed the protective vegetative layer is removed. This makes the soil highly unstable as there are not roots to stabilize it, no protective layer to reduce raindrop impact and increases surface runoff which all lead to increase levels of erosion. This causes heavy siltation in rivers as were seen to affect the Caroni River, north Oropuche and Aripo Rivers. This siltation runs out to the sea via rivers and in the case of Tobago where the coral reef is present it would have major deleterious effects as corals require clear water to grow as well as the silt could suffocate and kill them as they are highly sensitive. Siltation as a result of poor farming practices also blocks passages causing flooding also seen in an article published by GUARDIAN MEDIA LIMITED, 2014 and  it also affects breeding behaviours of the manatee in the Oropuche River. 

Photo 2 

Photo 2 taken at a farm in Barrackpore Trinidad shows the improper application of fertilizer to crops. This fertilizer was nitrogen and is suppose to be diluted before applying it to plants, however profit oriented farmers throw the undiluted fertilizer onto the land in hopes of gaining faster and bigger yields. On large farms the use of fertilizer is in excess again in order to maximize profits, but at what cost? Sadly major environmental degradation...The WRA report reviewed showed the effects of excessive use of agrochemicals led to eutrophication in rivers and coasts. This was a result of the high nutrient availability which cause algal blooms creating hypoxic conditions when carrying capacity was reached by the algae. As the algae decomposes it reduces the oxygen available and leads to marine organisms such as fish being staved of oxygen so they die. Furthermore agricultural waste produced such as agrochemicals, slurry and faeces from animals also led to coastal eutrophication when washed into waterways after heavy rains seen in Golden Grove Estate Tobago, this also greatly affects Rivers for example the Caroni River basin as illustrated by the report. Also in an article by the UNDP 2016, a Maracas Bay farmer, Mr. Ramnarine Rampray stated that heavy and excessive use of agrochemicals “kills the useful organisms in the soil like earthworms and bacteria that add natural nutrients to the soil” making it less fertile in the long term. 

Photo 3 

Photo 3 shows a tractor used on farmlands at a farm in Barrackpore. This is just one of the many different types of heavy machinery used in contemporary farming. These degrade soil quality as its shear weight running over the soil leads to soil compaction. Soil degradation was also by other means of agricultural practices according to GRACE Communications Foundation (GCF, 2016) and John VanDyk. 2004 of Iowa State University. GCF 2016 showed the environmental impact of monocrop farming was that it resulted in soil degradation as one type of crop is grown and no rotation occurs. Different crops use different nutrients from the soil and as such the practice of monocrop farming leads to soil degradation in the form of nutrient loss from soil. Also stated was the high use of mechanization on commercial farms resulted in soil compaction and erosion.  

Furthermore the effect of high mechanization was also illustrated by John VanDyk 2004 where it was seen that the use of tillage to prepare lands for planting resulted in negative contributions to soil quality. It was stated that fractures are produced in the soil after tillage, this causes disruption in soil structure which coupled with increase raindrop impact due to less crop residue leads to acceleration in surface runoff and soil erosion. Also “approximately half of plant-available phosphorus is concentrated in topsoil as is nearly all of the plant-available potassium” as erosion removes topsoil essential soil fertility levels are decreased. Tillage also leads to soil compaction occurs by the weight of the heavy machines driving over the soil which kills important microorganisms such as earthworms which help aerate the soil. 

The list is endless and something really needs to be done about this as the environmental cost is far too great. The profit driven mentality of farmers need to be changed and the improper practices need to be stopped. More sustainable approaches to agriculture should be conducted such as hydroponics and aquaponics. More sustainable practices can be read in the links provided.

Sustainable Agricultural Practices:

http://www.conserve-energy-future.com/sustainable-farming-practices.php

http://www.wikihow.com/Practice-Sustainable-Agriculture

http://www.iied.org/five-ways-make-farming-more-sustainable

http://www.newsday.co.tt/features/0,195274.html

More Articles on the effects of agriculture can be viewed below:

http://www.tt.undp.org/content/trinidad_tobago/en/home/ourwork/crisispreventionandrecovery/successstories/smallscalefarmers.html

https://guardian.co.tt/business-guardian/2011/06/30/issue-flooding

Reference:

The Water Resources Agency. "NATIONAL REPORT ON Integrating The Management of Watersheds and Coastal Areas in Trinidad and Tobago." March 2001. http://www.oas.org/reia/iwcam/pdf/trinidad and tobago/trinidad and tobago national report.pdf.

UNEP.org. "'PEOPLE AND THE NORTHERN RANGE'" 2004. Accessed March 24, 2016. http://www.unep.org/maweb/documents_sga/Trinidad Final Report.pdf.

Environmental Management Authority. "REPUBLIC OF TRINIDAD AND TOBAGO NATIONAL ENVIRONMENTAL POLICY." September 2009. Accessed March 24, 2016. http://www.ema.co.tt/new/images/policies/national-environmental-policy2006.pdf.

UNITED NATIONS DEVELOPMENT PROGRAMME. "ISSUES OF SUSTAINABLE DEVELOPMENT IN MARACAS VALLEY TRINIDAD & TOBAGO." July 2010. Accessed March 24, 2016. http://maracasvalley.org/MVAC/Docs/Volume 1.pdf.

"Deforestation." Deforestation and Climate Change. 2014. Accessed March 24, 2016. http://www.climateandweather.net/global-warming/deforestation.html.

"Soil Quality." GRACE Communications Foundation. Accessed March 24, 2016. http://www.sustainabletable.org/207/soil-quality.

"Industrial Crop Production." GRACE Communications Foundation. Accessed March 24, 2016. http://www.sustainabletable.org/804/industrial-crop-production.

Jacobsen, Michele. "Complementary Research Methods." Complementary Research Methods. Accessed March 24, 2016. http://people.ucalgary.ca/~dmjacobs/phd/methods/.

Lucas, Floyd, and Mary Alkins-Koo. "WATER RESOURCES MANAGEMENT A CASE STUDY IN POLLUTION IN A MAJOR RIVER CATCHMENT, TRINIDAD." Accessed March 24, 2016. http://www.bvsde.paho.org/bvsacd/cef-2/FLpollriv.pdf.

Simpson, Leslie Anthony. "POSSIBLE EFFECTS ON THE ENVIRONMENT OF AGRICULTURAL PRACTICES ON HILLSIDES IN THE CARIBBEAN." Accessed March 24, 2016. http://www.bvsde.paho.org/bvsacd/cef-2/LASagripra.pdf.

"The Issue of Flooding." The Trinidad Guardian Newspaper. Accessed March 24, 2016. https://guardian.co.tt/business-guardian/2011/06/30/issue-flooding.

"Good Agricultural Practices." Trinidad and Tobago's Newsday : Newsday.co.tt :. Accessed March 24, 2016. http://www.newsday.co.tt/features/0,195274.html.

Turner, B., and Rachel Catherine Allen. "What Are the Different Types of Crop Plants?" WiseGeek. Accessed April 05, 2016. http://www.wisegeek.com/what-are-the-different-types-of-crop-plants.htm#didyouknowout. 

United Nations Development Programme. "Safer Farming Practices Aids in Crisis Prevention." UNDP.org. Accessed March 24, 2016. http://www.tt.undp.org/content/trinidad_tobago/en/home/ourwork/crisispreventionandrecovery/successstories/smallscalefarmers.html.

"Global Warming Effects on the Economy." Union of Concerned Scientists. 2011. Accessed March 24, 2016. http://www.climatehotmap.org/global-warming-effects/economy.html.

VanDyk, John K. "Frequent Tillage and Its Impact on Soil Quality | Integrated Crop Management." Integrated Crop Management. June 28, 2004. Accessed March 24, 2016. http://www.ipm.iastate.edu/ipm/icm/2004/6-28-2004/frequenttill.html.  

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[1] Image taken from http://www.climate-change-guide.com/deforestation-and-climate-change.html Laurent Cousineau, 2016