Too Much Phosphorus Fertilizer: A Problem with 3x the Impact

Background

Phosphorus is an essential nutrient for plant growth. It is used in the production of chlorophyll, the green pigment that plants use to absorb sunlight and convert it into energy. Phosphorus is also used in the production of ATP, the energy currency of cells.

Too Much of a Good Thing

While phosphorus is an essential nutrient, too much of it can be harmful. Excess phosphorus can cause a number of problems, including:

• Eutrophication: Eutrophication is the process by which a body of water becomes enriched with nutrients, leading to a proliferation of algae and other aquatic plants. Algae can block sunlight from reaching underwater plants, causing them to die. The decomposition of dead algae can also lead to a decrease in oxygen levels in the water, harming fish and other aquatic organisms.
• Soil contamination: Excess phosphorus can also contaminate soil, making it less productive for growing crops. Phosphorus can bind to soil particles, preventing plants from absorbing it. This can lead to nutrient deficiencies in plants, which can reduce yields.
• Water pollution: Excess phosphorus can also pollute water sources, such as rivers, lakes, and streams. Phosphorus can be carried into water sources by runoff from agricultural fields or lawns. Once in water, phosphorus can contribute to eutrophication and other water quality problems.

Sources of Excess Phosphorus

The main source of excess phosphorus in the environment is agricultural runoff. Phosphorus is used in fertilizers to help crops grow. However, when fertilizer is applied to fields, some of it can be lost to runoff. Runoff occurs when water flows over the surface of the soil and carries away soil particles, nutrients, and other pollutants.

Other sources of excess phosphorus include:

• Septic tanks: Septic tanks are used to treat wastewater from homes and businesses. If septic tanks are not properly maintained, they can leak phosphorus into the groundwater.
• Animal manure: Animal manure contains high levels of phosphorus. If manure is not properly managed, it can be a source of phosphorus pollution.
• Industrial wastewater: Industrial wastewater can also contain high levels of phosphorus. Phosphorus can be released into wastewater from a variety of industrial processes, such as metalworking and food processing.

The Problem with Phosphorus

The problem with phosphorus is that it is a persistent pollutant. It can remain in the environment for long periods of time, and it can be difficult to remove. This means that even small amounts of phosphorus can have a significant impact on the environment.

The Impact of Phosphorus Pollution

Phosphorus pollution can have a wide range of impacts on the environment. These impacts include:

• Eutrophication: Eutrophication is the most common impact of phosphorus pollution. Eutrophication can lead to a number of problems, including:
  • Algal blooms: Algal blooms are caused by a proliferation of algae in water bodies. Algae can block sunlight from reaching underwater plants, causing them to die. The decomposition of dead algae can also lead to a decrease in oxygen levels in the water, harming fish and other aquatic organisms.
  • Fish kills: Fish kills can occur when oxygen levels in water bodies become too low. Fish and other aquatic organisms need oxygen to breathe, and when oxygen levels fall below a certain level, they can suffocate.
  • Loss of biodiversity: Eutrophication can lead to a loss of biodiversity in water bodies. Algae can outcompete other plants for nutrients, leading to a decline in the diversity of plant species. This can have a ripple effect on the entire food web, as fish and other animals that rely on these plants for food may also decline.
• Soil contamination: Excess phosphorus can also contaminate soil, making it less productive for growing crops. Phosphorus can bind to soil particles, preventing plants from absorbing it. This can lead to nutrient deficiencies in plants, which can reduce yields.
• Water pollution: Excess phosphorus can also pollute water sources, such as rivers, lakes, and streams. Phosphorus can be carried into water sources by runoff from agricultural fields or lawns. Once in water, phosphorus can contribute to eutrophication and other water quality problems.

The Cost of Phosphorus Pollution

Phosphorus pollution is a costly problem. The costs of phosphorus pollution include:

• Economic costs: Phosphorus pollution can have a significant impact on the economy. For example, eutrophication can lead to a decline in fish populations, which can hurt the fishing industry. Eutrophication can also lead to increased costs for drinking water treatment, as phosphorus can make water more difficult to treat.
• Environmental costs: Phosphorus pollution can also have a significant impact on the environment. Eutrophication can damage ecosystems and lead to a loss of biodiversity. Phosphorus pollution can also contribute to climate change, as algae can release methane, a greenhouse gas, into the atmosphere.

Solutions to Phosphorus Pollution

There are a number of things that can be done to reduce phosphorus pollution. These solutions include:

• Reducing fertilizer use: One of the most effective ways to reduce phosphorus pollution is to reduce the amount of fertilizer that is used on agricultural fields. Farmers can use soil tests to determine the amount of phosphorus that is already in the soil and only apply fertilizer as needed.
• Using low-phosphorus fertilizers: Farmers can also use low-phosphorus fertilizers to help reduce phosphorus pollution. Low-phosphorus fertilizers contain less phosphorus than traditional fertilizers, so they are less likely to contribute to phosphorus pollution.
• Improving manure management: Manure is a valuable source of nutrients for crops, but it can also be a source of phosphorus pollution. Farmers can improve manure management by storing manure properly and applying it to fields at appropriate rates.
• Improving wastewater treatment: Wastewater treatment plants can remove phosphorus from wastewater before it is released into the environment. Wastewater treatment plants can use a variety of technologies to remove phosphorus, such as chemical precipitation and biological nutrient removal.
• Restoring wetlands: Wetlands can help to remove phosphorus from water. Wetlands are natural areas that are covered in water for at least part of the year. Wetlands can filter phosphorus from water and store it in their soils.

Conclusion

Phosphorus is an essential nutrient for plant growth, but too much phosphorus can be harmful to the environment. Phosphorus pollution can cause eutrophication, soil contamination, and water pollution. The costs of phosphorus pollution are significant, both economically and environmentally. There are a number of things that can be done to reduce phosphorus pollution, including reducing fertilizer use, using low-phosphorus fertilizers, improving manure management, improving wastewater treatment, and restoring wetlands.

Additional Resources

• EPA: Phosphorus Pollution
• NRCS: Phosphorus Management
• Water Environment Federation: Phosphorus

Tables

| Table 1: Sources of Phosphorus Pollution |
|---|---|
| Source | Percentage of Total Phosphorus Pollution |
| Agricultural runoff | 60% |
| Septic tanks | 20% |
| Animal manure | 10% |
| Industrial wastewater | 10% |

| Table 2: Impacts of Phosphorus Pollution |
|---|---|
| Impact | Description |
| Eutrophication | A process by which a body of water becomes enriched with nutrients, leading to a proliferation of algae and other aquatic plants. |
| Soil contamination | A process by which soil becomes contaminated with phosphorus, making it less productive for growing crops. |
| Water pollution | A process by which water sources, such as rivers, lakes, and streams, become polluted with phosphorus. |

| Table 3: Costs of Phosphorus Pollution |
|---|---|
| Cost | Description |
| Economic costs | The impact of phosphorus pollution on the economy, such as the decline in fish populations and the increased costs for drinking water treatment. |
| Environmental costs | The impact of phosphorus pollution on the environment, such as the damage to ecosystems and the loss of biodiversity. |

| Table 4: Solutions to Phosphorus Pollution |
|---|---|
| Solution | Description |
| Reducing fertilizer use | Using soil tests to determine the amount of phosphorus that is already in the soil and only applying fertilizer as needed. |
| Using low-phosphorus fertilizers | Using fertilizers that contain less phosphorus than traditional fertilizers. |
| Improving manure management | Storing manure properly and applying it to fields at appropriate rates. |
| Improving wastewater treatment | Using technologies to remove phosphorus from wastewater before it is released into the environment. |
| Restoring wetlands | Restoring wetlands to help remove phosphorus from water and store it in their soils. |

Tips and Tricks

• Test your soil: Before you apply fertilizer, test your soil to determine the amount of phosphorus that is already present. This will help you to avoid applying too much fertilizer.
• Use low-phosphorus fertilizers: If you are using fertilizer, choose a low-phosphorus fertilizer. Low-phosphorus fertilizers contain less phosphorus than traditional fertilizers, so they are less likely to contribute to phosphorus pollution.
• Manage manure properly: Store manure properly and apply it to fields at appropriate rates. This will help to reduce the amount of phosphorus that is lost to runoff.
• Improve wastewater treatment: Wastewater treatment plants can remove phosphorus from wastewater before it is released into the environment. Talk to your local wastewater treatment plant about ways to improve phosphorus removal.
• Restore wetlands: Wetlands can help to remove phosphorus from water. Restore wetlands