Another severe disadvantage of pesticides is their effect on the environment. A severe consequence of using pesticides is a side effect known as ‘resurgence’. This is when the natural control of the pests is tampered with and disrupted due to the pesticides killing not only the pests but the pest’s predators too. The pests and their predators are temporarily eradicated and when the pests begin to increase in numbers there are insufficient predators to deal with them meaning the pests are allowed to severely increase in numbers which has an undeniably worse effect on the environment than if the pesticides weren’t used and consequently kill off the pest’s predators.
Another problem generating from the use of pesticides is bioaccumulation. This is when herbivores feed on plants which are contaminated with compounds such as chemical pesticides; the compounds tend to become concentrated in the fatty tissues of the animal. In the animal, these compounds are not broken down and are not removed in the urine, which otherwise means they are non-biodegradable. When the herbivore is then consumed by a predatory carnivore, the compounds are then passed into the carnivore which subsequently leads to an accumulation of pesticide along the food chain.
Pesticides were often used repeatedly over the course of many years consecutively. This would very often result in the pest becoming resistant to the pesticide. This would happen if when the pests were sprayed with the pesticide, not all the pesticides will be killed as those with slight variations in their genetic make-up would be resistant and hence survive. Every generation of pest coming from these surviving pests will also be resistant to the pesticide, and subsequently the pests will multiply and become almost entirely resistant to the pesticide. This will often make matters worse as farmers not knowing what to do will increase the concentrations of pesticides they use which can be potentially increasingly harmful due to the pesticides poisonous nature.
Another problem the environment has to face due to pesticides is known as ‘persistent organic pollutants’ (POPs). POPs poison non-target organisms in the environment and increases the chances of human disruption of the endocrine system, cancer, infertility and mutagenic effects. However these are at this point not complete in being backed up by sufficient evidence and research. Due to these potential health risks, the cost of developing new pesticides has risen dramatically over the past few years. The government has become involved and slowed the progress and development of pesticides and increasing the costs of the new products. This combined with the fact that pesticides have short market lives due to developed resistance by pests makes pesticides gain lower profits for the producers of these products.
However despite the clear disadvantages of pest control there are also many clear advantages of using them. The most blatant advantage of using pesticides is that they are very easy accessible and available for relatively low prices. Pesticides are also very easy to use for farmers and this contributes to their popularity over other means of pest control.
It is widely thought that pesticides are exploitatively expensive, considering they have to be distributed over such wide areas of land; however this is proven to be incorrect. Pesticides are very cost effective and require less human labour to maintain the pesticide process. The pesticides can be used in a way in which the pests do not become resistant to it, this can be done by adhering to the proper precautions such as using no more than the recommended allowance, and then the chemical control of pests is a safe and effective option. There are three types of biological control; Classical Biological Control (importation) involves traveling to the country or area from which a newly introduced pest originated and returning with some of the natural enemies that attacked it and kept it from being a pest there. Augmentation is a method of increasing the population of a natural enemy which attacks a pest. This can be done by mass producing a pest in a laboratory and releasing it into the field at the proper time. Another method of augmentation is breeding a better natural enemy which can attack or find its prey more effectively. Conservation of natural enemies is an important part in any biological control effort. This involves identifying any factors that limit the effectiveness of a particular natural enemy and changing them to help the beneficial species. Conservation of natural enemies involves either reducing factors which interfere with the natural enemies or providing needed resources that help natural enemies.
Another important and effective type of pest control used in the world today is biological control. This method is considered the ‘organic’ way of keeping pest levels low. It involves the introduction of the pests predator into the area where the pest is present and allow the predator to naturally consume any pest that it encounters. This is obviously advantageous as the natural balance in the ecosystem remains undisturbed, which is not always the case with pesticides which may eradicate not only the pest but the predator itself, which consequently disrupts the flow in this food chain and overall ecosystem.
A slight disadvantage with biological control however is that not all the pests are eradicated by this method, meaning that it takes more intensive management and planning in finding a balance that has to be found proportionately to the amount of pests and predators released. This can be tedious and may be extremely time consuming until a balance is found. Biocontrol is used more effectively against pests with high tolerance levels, i.e. pests that may defoliate plants but not significantly impact crop yields. In a lot of cases biological control can be more expensive that pesticide use and often the results are not as dramatic or quick as pesticide use either. Another problem with biological control is that the predator itself may have a negative effect on the crops and may also begin consuming the plants, which has a consequently counteractive effect on what was originally supposed to occur. Also on the upper hand however is that with biological control there are no potentially harmful effects on humans that chemical pesticides have a high probability of causing. This means that biological control is overall a safer method of pest control than the use of chemical pesticides.
In conclusion, it is fair to say that both types of pest control; pesticides and biological control have their advantages and disadvantages and it may depend on the type of crop or plant that the individual farmer grows that may decipher upon which system is most beneficial to that farmer. Pesticides have the disadvantage of their potentially dangerous and harmful chemical properties which are easily spread, however they are relatively cheap and effective. Biological control is advantageous for its lack of harmfulness to the environment and it’s preserving of nature, however the process needs more research and is more time consuming and more difficult to fine tune.
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