Although these pesticides protect our crops from severe losses due to pests, they have several side-effects as listed below: The unprecedented damage to farmland caused by the dust bowl storms of the s focused national attention on the need for soil and water conservation measures to maintain farm productivity.
Farming is one potential source of such contamination. However, it is carried with eroded soils into surface water bodies, where it may cause excessive growth of aquatic plants. Potassium, the third major nutrient in fertilizers, does not cause water quality problems because it is not hazardous in drinking water and is not a limiting nutrient for growth of aquatic plants.
During the s and s American farmers depended on cheap energy, plentiful water supplies, and extensive use of chemical fertilizers and pesticides to produce high yields with decreasing labor on reduced amounts of land. This is called "Eutrophication".
This has enhanced the possibilities of soil-erosion and easy movement of chemical contents to the lower horizons. The purpose of this extension series is to build such understanding, and the remaining bulletins explain how agricultural chemicals affect human health, how they get into drinking water, and how such contamination can best be prevented.
Department of Agriculture and granting public land to the states for establishment of agricultural colleges. A recent study estimated the off-site cost of cropland erosion in the United States to be in the range of a billion dollars per year Clark, Haverkamp, and Chapman A vigorous market soon developed for soil amendments such as guano, manure, crushed bone, and lime; and by seven factories had been established in the United States to manufacture mixed chemical fertilizers.
Although the intensification of agriculture has vastly increased productivity, it also has had a number of potentially detrimental environmental consequences, ranging from rapid erosion of fertile topsoils to contamination of drinking water supplies by the chemicals used to enhance farmland productivity.
The three major nutrients in fertilizers are nitrogen, phosphorus, and potassium. Water logging also leads to low mechanical strength of soil and low crop yield.
This is called "Eutrophication". Fertilizer application in South Asia including India has multiplied with widespread introduction of the Green Revolution. Nationwide sampling for pesticides has been quite limited, but 23 states have reported at least one of 22 pesticides in groundwater.
This again has forced the pace of agricultural development to be maintained, so that teeming millions do not starve. The high-yielding varieties and the monoculture practices led to material change in the pest complex. Fields were dug by oxen pulling wooden plows, seeds were broadcast by hand, and grains were harvested with scythes just as they had been for the previous 2, years.
Saline soils are characterized by accumulation of soluble salts like sodium chloride, calcium chloride, magnesium chloride, sodium sulphate, sodium carbonate and sodium bicarbonates. Small farms growing a wide variety of crops have in large part been replaced by much larger farms consisting of extensive fields of a single crop.
The mids began an era of great change in American agriculture, influenced by the British agricultural revolution, which brought advances in cultivation methods, breeding of improved crop varieties, and use of fertilizers and crop rotations to maintain soil productivity.
Up to a certain point, increased fertilization and irrigation will compensate for the lower soil fertility. Considering this, it becomes essential to understand the related incidences causing environmental degradation.
The consequences for long-term crop yields have not been adequately quantified. Skies were blackened as far east as New York City, and even ships miles out in the Atlantic Ocean reported dust accumulations on board.
Once the effect of the pesticide wears off, the pest species is likely to recover more rapidly than its predators because of differences in the available food supply.
Expansion of natural limits. Death of non-target organisms: Excess Nitrogenous fertilizers applied in fields leach deep into the soil contaminating the groundwater. Their life is short, they die and pollute water thereby affecting aquatic life in the lake.
It leads to desertification i. Invention of machines for tilling, planting, reaping, and threshing vastly increased farm efficiency in the mid s.Historically, man as hunter-gatherer could not affect the environment because he was using the natural population of animals and plants well below the sustainable yields except in those areas where Short essay on the Effects of Modern Agriculture.
Agriculture has been a major component of the United States economy ever since colonial days, when 9 out of 10 working persons were employed on a farm.
Produclivity of American agriculture has tripled since then, and today only 3 percent of our labor force produces enough food and fiber to meet.
As land became less available for settlement in the West, people became more interested in maintaining soil fertility and increasing crop yields on their existing farms.
Read this article to learn about the effects of modern agricultural practices on environment: Agriculture is one of the oldest professions which include the largest sector of Indian population (70%).
Modern agricultural practices have substantially changed the farming, crop production and harvesting.Download