1. Insects develop chemical resistance chart. As a result, the one with the insect pest. When using a chemical insecticide, is continuing to develop chemical resistance chart. They developed the ability to withstand the chemicals that are poisonous, and convey such resistance chart to its descendants will make religion of insects can survive. From our study, researchers found that only 50 years ago that the chemicals are used. 400 types that have developed immunity to various types of insecticide resistance, which makes the need to use pesticides that are more concentrated, or switch to a new type of insecticide, such as in the case of cotton worm in the beginning anchor penetration in recent years Wed.Prof. 2503 (1960) sandidithi used to kill the worm uses sandidithi just 0.03-worm body weight at one g/g, but only 5 years after that to increase the quantity is 1000-Li's death, Helen g. (Raven, Berg, Johnson, 1993. As a result, 500) by the farmers need to use chemicals to get rid of the insects in more dirty or not, change to new types of chemicals used to control pest control, but as a result,
2. To destroy the equilibrium of the system, nawet Not only does the pest to die down. When agricultural chemicals are used, but many organisms in agricultural ecosystems, especially the most useful insect that acts to control pests or insects decorating graves, son. The study found that the natural enemies of pest insects eat food such as Spider beetles; Ladybug Diamond beetle kill, there will be a population decreased significantly after a chemical insecticide spraying. And indirectly by having lower pest insects, there is not enough food, but not too long after that. Pest population will increase rapidly. While natural enemies will require a longer period. The balance of the ecosystem and thus lost. Causes of the outbreak of the insect pest. thus becomes whether to use pesticides do not help prevent the spreading of the pest, which corresponds to the research in the United States. TrProf. 2488-2532 (1989) insecticide chemicals used increase more than 33 times the yield loss rate, but due to the outbreak of the insect remains in level 13% unchanged (Raven, Berg, Johnson, 1993. 501). Insects in the past may not be the natural enemies of pest control because it has a mandate to the population, is low, but when pesticides, natural enemies decreases until. Until it becomes a pest, such as how the European Red case, which has never been found in Apple garden in United States. The outbreak was originally very much after it has been started with the chemical insecticide (Raven, Berg, Johnson 1993, 502)
3. The accumulation of chemicals in the food chain. Pesticides, it does not remain only in the agricultural area, but often spread out in the environment because the water that flows through agricultural conversion has been spraying pesticides. Causes of contamination of chemicals in widespread ecosystem The creature in the water source may be directly affected by these chemicals. Especially the effect on the immune system of fish, fish resistance to various diseases. These chemicals, particularly in the Boston group check box to watching a slow digestion, it is no surprise that the Rhine could be accumulated in the body of the creature, and convey to the creatures at the top of the food chain. (Biological magnification): for example, in the picture, which is the accumulation of DDT in the food chain from contamination of DDT in water at a rate of just 0.But in the section on 3 million small creatures that live in the water, such as red, Red worms, they will discover that they have accumulated DDT in these animals is increased by 0.4 million in parts and in the fish that eat smaller food organisms is the accumulation of DDT in fish up to 2 parts in a million parts and when the birds eat the fish food will have accumulated DDT in up to 25 million in the best one
.Although the birds are accumulated DDT in a somewhat extreme, but this may not be retained, the bird dies immediately, but it has other side effects, such as DDT contained in the birds will make some of the eggshell. As a result, the egg crack while hatching. To work around this issue. Not limited only to birds that eat fish, including birds that eat insects and birds that eat the fruit as well.
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