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=There is Much to Learn from Past Agricultural Practices= ====In the early 1900s, 33 million people people in the US worked and lived on farms. So much has changed over time, that today only 2 million people are engaged in commercial farming. Using the pesticides and fertilizers can be a risk for some crops. Fertilizers will help a plant grow, but they can also be transfered into streams, rivers, ponds, and lakes. Run off from fields can effect drinking water and human health as a result. Drinking water that containing high concentrations of nitrate ions, which are the main ingredient in fertilizers. Nitrate ions in the bloodstream compete with oxygen for positively charged ions, and can for anemia. If topsoil is in bad condition it can affect your health as well. Synthetic fertilizers dont have any organic bulk and they provide a good food source for soil microoganisms and earthworms. Treated with certain fertilizers lose biological activity and diminishes soils fertility. Chalky soils lose their capacity to hold water.====

====Over the past 100 years, damaging farming practices have decreased the amount of topsoil in parts of the United states by 50 percent. **Salinization:** after irrigation, water evaporates from farmland and tsalts are left behind and over time repeated irrigation causes salinity of the soil to increse. This causes rapid decrease in productivity.====



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