Over long time, human food and clothing depended mainly on agriculture. While ever since the historical time, agriculture had always relied on plenty of human labor, which was subject to various kinds of natural conditions. So the development of agriculture was very slow. In the course of the nineteenth century, the usage of agricultural machinery gradually improved the working conditions. However, in agricultural production, it was the application of chemical fertilizers and pesticides that really elevated the agricultural output in per unit area.
Observe shows that, amongst all of the measures to extend the agricultural production, the position played by chemical fertilizers is 40% to sixty five%. On the basis of the booming within the petrochemical trade, artificial ammonia and urea have realized large-scale production, which makes the output of chemical fertilizer occupy a big proportion within the chemical products. In 1985, the total output of chemical fertilizer on the planet amounted to approximately one hundred forty million ton, which made it become one of the bulk chemical products. In recent years, the development of nitrogen, phosphorus and potassium compound fertilizer and trace parts fertilizer has additional meet the calls for of various soil structures and totally different crops.
In the early period, people used natural animals, plants and minerals to forestall and deal with crop pests and diseases. Until the late nineteenth century, after the formation of contemporary chemical business, individuals began to make use of arsenic preparation to kailing beetles on potato, and use Bordeaux mixture to forestall and deal with downy mildew on grapes, in order that agriculture began a new period of chemical prevention and treatment. During the 1940s, loads of pesticides and herbicides, reminiscent of organic chlorine, organic phosphorus, have been produced and widely utilized in agriculture, forestry, animal husbandry and public health. However, among the pesticides throughout this period were rich in residues or poison, which caused ecological pollution, so that they had been banned by many countries.
In recent years, a number of efficient, low-residue, low-poisonousity pesticides have been developed, together with pyrethroid, which is a bionic pesticide and won’t pollute the environment. It has been put into industrial production. Consequently, bio-pesticides have grow to be probably the most active areas in pesticide research currently.
What’s more, plastic film (similar to high pressure polyethylene, linear low density polyethylene, etc.) has been applied in modern agriculture, which is used for mulching film or greenhouse seedlings. It might probably significantly enhance the output of the crops, so it is now being popularized on a big area.
When you loved this article and you would like to receive details regarding Echemi please visit the webpage.