Pesticides Essay, Research Paper
Should we be concerned with the extensive use of pesticides by farmers? I believe we should be aware of the consequences of pesticide use. The more we are exposed to pesticides, the greater the risk there is to the environment and our health. They are responsible for many environmental problems such as water pollution, soil degradation, and insect resistance. I will look at all the environmental impacts caused by pesticide use. But what led to the rise of the use of pesticides? Tremendous increase in crop production, profits, and pest control due to pesticide use are some of the reasons for this increase. There are many theories, which explain the rise of pesticides, and the influence pesticides have had on land use decisions by farmers. I will discuss several theories that try and explain this. Farmers have moved towards different farming techniques such as massive production of a single crop instead of the traditional style of producing several crops. Techniques such as these have resulted from the use of pesticides. An example of all this is in the Philippines. The government in the Philippines has given considerable attention to the environmental and health impacts of pesticides and has implemented strategies to decrease the impacts. Many empirical studies have been done on the Philippines, and I will look at several of these. Lastly, I will discuss the future research of pesticides and how we are looking towards a decrease in the use of pesticides, and how the amount of pesticide use has decreased in the past twenty years. But firstly, I will explain what a pesticide is.
What exactly is a pesticide? Well, pesticides are chemicals that kill or suppress pests. There are three main types of pesticides: herbicides, insecticides, and fungicides. Herbicides are the type of pesticides that act against weeds, while insecticides act against insects, and fungicides act against fungi (Reuveni, 1995). There are two classes of pesticides, organic and inorganic. All pesticides are toxic and have some effect on the environment and our health. We are still looking for the ideal pesticide, which targets only the insects we want, and is harmless to the environment. Pesticides have provided highly effective and relatively easy control of plant pests for the past one hundred years. The first major commercial pesticides were an arsenic compound introduced in 1867 to control insects and a copper-based preparation in 1885 to control fungi attacking grapes (Reuveni, 1995). However, a rapid increase in their use began in the 1930?s and 1940?s following the discovery of synthetic organic chemicals, such as DDT and thiram. With the discovery of these pesticides, farmers began using them more often. We have been familiar with pesticides for a long time now, and have discovered many benefits a long with many environmental impacts that come along with the use of pesticides.
Chemical pesticides cause widespread environmental problems and are the only toxic chemical deliberately introduced into the environment. Some problems include insect resistance, water pollution, destruction of non-target animals, soil degradation, ozone depletion, and localized pollution (Cooley, 1995; Crissman, 1998; Dinham, 1993; Reuveni, 1995). Over-use of pesticides creates insect resistance, destruction of natural enemies, and a resurgence of pest species leading in turn to increased spaying, which is also known as ?the pesticide treadmill? (Dinham, 1993). A good example of this is in Gezira where they are dependent on cotton production. After World War II, pesticides were introduced in Gezira and the pesticide use increased steadily after the 1940?s. By 1976, pesticide use had reached 2,500 tonnes a year. Cotton production costs quadrupled over ten years, while yields fell to the same yields obtained before World War II. After a while, yields ended up being the same because of the pest resistance. The only change in Gezira from World War II till the early 1980?s were the widespread introduction of pesticides. The amount of cotton they produced remained about the same (Dinham, 1993). This shows that over-use of pesticides will take away from the advantages of using pesticides.
Another environmental impact caused by pesticides is water pollution. Residues from the pesticides leach into the water, which are harmful to anything in the water. A study was done for Lake Ichkeul in the North of Tunisia. This is an important bird sanctuary and a unique ecosystem because it is connected to the sea by a narrow channel, and renewal of its waters is rather slow. It also collects water from many small rivers, which cross a densely cultivated area, in which lager amounts of pesticides are used. The study showed after examining the lake sediments and bird?s eggs that they contained organochlorine and PCB residues (Cooley, 1995). Residues of pesticides have been found in many other bodies of water. Along with this, a pesticide hasn?t been found yet to target only the insect we want it to destroy. So, it not only kills pests but some other non-target animals as well. Fish in the waters that are contaminated with pesticide residues often die leading to a decrease in fish yields and losses of traditional fishing grounds. As well, intoxication of fish, birds, cattle, and wild animals is common during spraying season. The death of birds and fish due in part to pesticides is most common, which has led to bans of certain pesticides in some places (Stevens, 1994). This makes people wonder if it?s even worth using pesticides.
Soil degradation is another big problem due to pesticides. After pesticides are being used, they stay in the soil in which they were used, which causes the soil to be less healthy. Nutrients are lost in the soils, and certain crops won?t be able to grow on that particular soil (Keen 1992). The increase use of pesticides led to more of a monoculture style of farming, which meant that crops weren?t rotated on the fields. This doesn?t leave enough time for the soil to get the nutrients it needs to be considered a ?good soil.? As well, some pesticides are ozone depleters, which contribute to the greenhouse effect. Apart from large-scale impacts, pesticides cause localized pollution as well. Disposal of unwanted containers threatens both the environment and health. Lack of hazardous awareness and of alternative disposal methods, means that agricultural areas are littered with empty containers. A survey in Paraguay revealed that 24 percent of farmers threw empty containers into streams, sewers, ditches, or drainage channels (Dinham, 1993). All of these are impacts that pesticides have on the environment. If they are so many detrimental effects to the environment, what then, motivates a farmer to use pesticides on their farm?
Pesticides have many advantages that motivate farmers to use them. Pesticides are an important part of the technology used to control plant pests. They can be extremely effective, which in turn leads to an increase in the production of crops (Cooley 1995, Dinham 1993). The more crops a farmer produces means the more money he/she can make off of them. Another factor which motivates farmers to use pesticides is the fact that they are easy to use. As soon as a farmer realizes that they are fairly simple to use, it will increase the chances they will use them more often. As well, pesticides permit cultivation of crops in otherwise unsuitable areas. If farmers have land that is unsuitable, they see that the use of pesticides will allow them to cultivate on those fields. But the greatest motivation factor that farmers have is the profits they gain from pesticides. The investment of pest control by pesticides has been shown to provide significant economic benefits (Pimentel, 1993). Pesticides provide the producer in North America with a return of three to five dollars for every dollar invested (Reuveni, 1995). This is more of a profit that a farmer would receive if he/she didn?t use pesticides. But what has led to this rise in the use of pesticides?
Pesticide use has increased since the early 1900?s. There have been many theories that have come about of why there was a rise in pesticide use. Pesticides contribute to our ability to feed a rapidly expanding world population. Every year there are more and more people on this earth and we need more and more food to feed everyone. Pesticides produce large quantities of crops in a short time-span. In the past 100 hundred years, larger needs for food have been met primarily by increasing productivity per unit of land. It has been estimated that with the use of pesticides, yields are thirty to thirty-five percent more on average than they would be with the presence of pests (Hussey, 1985). Pests cause severe economic losses for growers and widespread food shortages, starvation, and disintegration of human communities. It is essential for humans to take action to limit the destruction of food crops by pests. Crop pests must be controlled to protect the security of the world food supply. Pesticides also protect humans against insect-borne diseases. The single most beneficial use of pesticides has been the protection of more than five hundred million people from malaria (Reuveni, 1995). During the 1940?s to the 1960?s, great reliance was placed on pesticides to control insects, mites, and fungi. Pesticides were so effective, however, the growers relied on them to the exclusion of other pest control practices. This led to the overuse of pesticides.
The use of pesticides led to changes in land use by farmers. Farmers have moved more towards a monoculture style of farming (Dinham, 1993). With pesticides, farmers are able to produce massive amounts of a single crop and profit off of it. The process of crop rotation is nullified because of the technique of only cropping one crop. As well, farmers began using pesticides on only a certain percentage of its crops. As long as the farmer separates his/her crops in an appropriate manner, all of the crops are protected from pests. For example, a farmer may put pesticides on only the first ten percent of its crops, and leave the next 10 percent pesticide free, then put pesticides on the next 10 percent and so on. Techniques such as these have been done to reduce the amount of pesticides that are used. Lots of places have had concerns with the increase in pesticide use and have tried to decrease the amount used like the Philippines.
The use of pesticides in Philippine agriculture continues to increase despite the adoption and promotion of the Integrated Pest Management. Insecticides constitute approximately fifty-five percent, fungicides twenty-two percent, and herbicide sixteen percent of the pesticides used in the country for rice, corn, vegetables, and plantation crops (Pingali, 1995). The extensive use of pesticides and the risks they pose to human health and the environment are now the focus of national concern and interest. The main environmental problems they are concerned about are ground and surface water pollution, resistance of pests to pesticides, and the impact it has on non-target organisms. They have tried to solve these problems by having stricter regulations on the use of pesticides. Also they have been developing more practical, economical, and less environmentally disruptive pest control methods instead of using pesticides. They have also had continuous development and conduct of research and giving training to researchers, extension workers, and farmers (Pingali, 1995).
Despite these government efforts, however, facilities and trained technical personnel are still inadequate to effectively deal with pesticide related problems and concerns. The country needs to further upgrade its existing laboratory facilities, provide adequate funding for their efficient operation, continuously provide manpower development and promote more conscious efforts between the government and the private sector toward minimizing pesticide hazards. Even with all these government policies in place, the use of chemical pesticides still provides the main line of defense against pests in crop production activities in the Philippines. Despite the availability of alternatives to pesticide use, the use of them still has been increasing. Pest protection is quite critical in a country like the Philippines where agriculture is its major industry, accounting for thirty-six of its export earnings, and twenty-eight percent of its Gross National Product (Davis, 1993). Furthermore, around forty-three percent of the country?s total land area of approximately thirty million hectares is devoted to agricultural production, providing livelihood for approximately seventy percent of its population (Davis, 1993). The use of pesticides is expected to continue to be a significant component in Philippine agriculture. But, it seems inevitable that less pesticide will be used in the future.
Research for the future is being done to decrease the use of pesticides. Greater reliance will be placed on biologically based technology. It has been estimated that pesticide use could be reduced by thirty-five to fifty percent in the United States without lowering crop yields or causing an increase in the price of food (Reuveni, 1995). Some techniques that people are thinking of to protect plants against pests without using pesticides are improving the defenses of the plant and by reducing the destructiveness of the pest. Both these techniques could be done if enough effort and thought is put into them. Biotechnology has been increasing tremendously lately and it seems it will be a big part of agriculture in the near future.
It looks like there is going to be a decline in the use of pesticides. Is this a good thing or a bad thing? Well, pesticides create many environmental problems such as pest resistance, water pollution etc. and with the decrease use, it will benefit the environment. But without pesticides we could not produce certain crops economically or meet present world food demands. Pesticides create increase in profits and in production and eliminate unwanted pests. These are the reasons that motivate farmers to keep using pesticides. So the answer to that question can go either way. The Philippines shows how they are trying to decrease the use of pesticides but yet the use of them keeps increasing. It seems though we are headed towards the elimination of pesticides and an increase in biotechnology. All of this suggests that it is essential that careful assessment be made to evaluate the benefits and risks of pesticides.
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