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Fertilizer effect on soil

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career point university
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The document discusses the effects of fertilizers and pesticides on soil and water, noting that nitrogen fertilizers can acidify soils while nitrate-based products are less acidifying, and that overuse of nitrogen fertilizers and pesticides is a major cause of water pollution through nutrient runoff leading to eutrophication. It also outlines how different forms of nitrogen and phosphorus fertilizers impact soil pH and chemistry.

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Career Point Cares Soil Chemistry, Fertility and Nutrient Management (AGL406) Mr. Rohitashv Nagar Assistant Professor & HOD Department of Agronomy School of Agricultural Sciences Career Point University, Kota (Raj.)
Career Point Cares Lecture-2 Fertilizer and pesticides & their effect on soil and water
Career Point Cares Fertilizer effect on soil Use of mineral or organic fertilizers in agriculture increases inputs of nutrients to soils, and the form in which the nutrients are applied and their fate in the soil-plant system determine the over all effects on soil pH. Macronutrients (N, P, K) have the major effects on pH as they are added in much larger quantities to soil than micronutrients.
Career Point Cares Fertilizer effect on soil 1. All the major fertilizer nutrients, nitrogen is the main nutrient affecting soil pH, and soils can become more acidic or more alkaline depending on the type of nitrogen fertilizer used. 2. Nitrate-based products are the least acidifying of the nitrogen fertilizers, while ammonium-based products have the greatest potential to acidify soil. 3. Soil acidification due to use of phosphorus fertilizers is small compared to that attributed to nitrogen, due to the lower amounts of this nutrient used and the lower acidification per kg phosphorus. Phosphoric acid is the most acidifying phosphorus fertilizer. 4. Potassium fertilizers have little or no effect on soil pH.
Career Point Cares The form of N and the fate of N in the soil-plant system is probably the major driver of changes in soil pH in agricultural systems. Nitrogen can be added to soils in many forms, but the predominant forms of fertilizer N used are urea (CO(NH2)2), monoammonium phosphate (NH4H2PO4), diammonium phosphate ((NH4)2HPO4), ammonium nitrate (NH4NO3), calcium ammonium nitrate (CaCO3+NH4(NO3)) ammonium sulfate ((NH4)2SO4), urea ammonium nitrate (a mixture of urea and ammonium nitrate) and ammonium polyphosphate ([NH4PO3]). ammonium- based fertilizers will acidify soil as they generate two H+ ions for each ammonium molecule nitrified to nitrate. Nitrate-based fertilizers have no acidification potential and actually can increase soil pH as one H+ ion is absorbed by the plant (or OH- excreted) in the uptake of nitrate.
Career Point Cares MAP = monoammonium phosphate, DAP = diammonium phosphate, SoA = sulfate of ammonia, CAN = calcium ammonium nitrate.
Career Point Cares The form of P fertilizer added to soil can affect soil acidity, principally through the release or gain of H+ ions by the phosphate molecule depending on soil pH. If phosphoric acid (PA) is added to soil, the molecule will always acidify soil as H+ ions will be released - one H+ ion if the soil pH is less than 6.2 and two H+ ions is the soil pH is above 8.2. Monoammonium phosphate (MAP), single superphosphate (SSP) and triple superphosphate (TSP) all add P to soil in the form of the H2PO4 - ion, which can acidify soil with a pH greater than 7.2 but has no effect on soil pH in acidic soils. The form of P in diammonium phosphate (DAP) is HPO4 2- which can make acidic soils (pH<7.2) more alkaline but has no effect on soil with a pH>7.2. Crop uptake of P has little effect on soil acidity due to the small amounts of fertilizer P taken up.
Career Point Cares The type of phosphate ions present in the soil solution depends on the soil pH. In soils having neutral to slightly alkaline pH, the HPO4 2- is the most common form. As the soil ph gets lowered and it becomes slightly too moderately acidic, both HPO4 2- and H2PO4 - ions prevail. At higher soil acidity, H2PO4 - form tend to dominate.
Career Point Cares MAP = monoammonium phosphate, DAP = diammonium phosphate, SSP = single superphosphate, TSP = triple superphosphate, APP = ammonium polyphosphate.
Career Point Cares Pesticide effect on soil The term pesticide covers a wide range of compounds including insecticides, fungicides, herbicides, rodenticides, nematicides, plant growth regulators and others. Soil can be degraded and the community of organisms living in the soil can be damaged by the misuse or over use of pesticides. Some pesticides are more toxic to soil organisms than others. Some pesticides may break down quickly when applied to soils, while others may persist for longer periods. The type of soil and the type of pesticide can also affect pesticide persistence.
Career Point Cares Fertilizer and pesticides effect on water Due to the excessive use of N fertilizer and pesticides is regarded as the most important fertilizer-related pollution issue. Nutrient enrichment, eutrophication of surface-water quality due to transportation of nutrients applied through fertilizers via leaching, runoff and sediment erosion is another problem. Eutrophication: excessive richness of nutrients in a lake or other body of water, frequently due to run-off from the land, which causes a dense growth of plant life.
Career Point Cares
Career Point Cares

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Fertilizer effect on soil

  • 1. Career Point Cares Soil Chemistry, Fertility and Nutrient Management (AGL406) Mr. Rohitashv Nagar Assistant Professor & HOD Department of Agronomy School of Agricultural Sciences Career Point University, Kota (Raj.)
  • 2. Career Point Cares Lecture-2 Fertilizer and pesticides & their effect on soil and water
  • 3. Career Point Cares Fertilizer effect on soil Use of mineral or organic fertilizers in agriculture increases inputs of nutrients to soils, and the form in which the nutrients are applied and their fate in the soil-plant system determine the over all effects on soil pH. Macronutrients (N, P, K) have the major effects on pH as they are added in much larger quantities to soil than micronutrients.
  • 4. Career Point Cares Fertilizer effect on soil 1. All the major fertilizer nutrients, nitrogen is the main nutrient affecting soil pH, and soils can become more acidic or more alkaline depending on the type of nitrogen fertilizer used. 2. Nitrate-based products are the least acidifying of the nitrogen fertilizers, while ammonium-based products have the greatest potential to acidify soil. 3. Soil acidification due to use of phosphorus fertilizers is small compared to that attributed to nitrogen, due to the lower amounts of this nutrient used and the lower acidification per kg phosphorus. Phosphoric acid is the most acidifying phosphorus fertilizer. 4. Potassium fertilizers have little or no effect on soil pH.
  • 5. Career Point Cares The form of N and the fate of N in the soil-plant system is probably the major driver of changes in soil pH in agricultural systems. Nitrogen can be added to soils in many forms, but the predominant forms of fertilizer N used are urea (CO(NH2)2), monoammonium phosphate (NH4H2PO4), diammonium phosphate ((NH4)2HPO4), ammonium nitrate (NH4NO3), calcium ammonium nitrate (CaCO3+NH4(NO3)) ammonium sulfate ((NH4)2SO4), urea ammonium nitrate (a mixture of urea and ammonium nitrate) and ammonium polyphosphate ([NH4PO3]). ammonium- based fertilizers will acidify soil as they generate two H+ ions for each ammonium molecule nitrified to nitrate. Nitrate-based fertilizers have no acidification potential and actually can increase soil pH as one H+ ion is absorbed by the plant (or OH- excreted) in the uptake of nitrate.
  • 6. Career Point Cares MAP = monoammonium phosphate, DAP = diammonium phosphate, SoA = sulfate of ammonia, CAN = calcium ammonium nitrate.
  • 7. Career Point Cares The form of P fertilizer added to soil can affect soil acidity, principally through the release or gain of H+ ions by the phosphate molecule depending on soil pH. If phosphoric acid (PA) is added to soil, the molecule will always acidify soil as H+ ions will be released - one H+ ion if the soil pH is less than 6.2 and two H+ ions is the soil pH is above 8.2. Monoammonium phosphate (MAP), single superphosphate (SSP) and triple superphosphate (TSP) all add P to soil in the form of the H2PO4 - ion, which can acidify soil with a pH greater than 7.2 but has no effect on soil pH in acidic soils. The form of P in diammonium phosphate (DAP) is HPO4 2- which can make acidic soils (pH<7.2) more alkaline but has no effect on soil with a pH>7.2. Crop uptake of P has little effect on soil acidity due to the small amounts of fertilizer P taken up.
  • 8. Career Point Cares The type of phosphate ions present in the soil solution depends on the soil pH. In soils having neutral to slightly alkaline pH, the HPO4 2- is the most common form. As the soil ph gets lowered and it becomes slightly too moderately acidic, both HPO4 2- and H2PO4 - ions prevail. At higher soil acidity, H2PO4 - form tend to dominate.
  • 9. Career Point Cares MAP = monoammonium phosphate, DAP = diammonium phosphate, SSP = single superphosphate, TSP = triple superphosphate, APP = ammonium polyphosphate.
  • 10. Career Point Cares Pesticide effect on soil The term pesticide covers a wide range of compounds including insecticides, fungicides, herbicides, rodenticides, nematicides, plant growth regulators and others. Soil can be degraded and the community of organisms living in the soil can be damaged by the misuse or over use of pesticides. Some pesticides are more toxic to soil organisms than others. Some pesticides may break down quickly when applied to soils, while others may persist for longer periods. The type of soil and the type of pesticide can also affect pesticide persistence.
  • 11. Career Point Cares Fertilizer and pesticides effect on water Due to the excessive use of N fertilizer and pesticides is regarded as the most important fertilizer-related pollution issue. Nutrient enrichment, eutrophication of surface-water quality due to transportation of nutrients applied through fertilizers via leaching, runoff and sediment erosion is another problem. Eutrophication: excessive richness of nutrients in a lake or other body of water, frequently due to run-off from the land, which causes a dense growth of plant life.