Fertilizer Pollution: Global Water Crisis And Country Impact

Excessive fertilizer use has become an increasingly pervasive global problem, with nitrates from fertilizers polluting water bodies worldwide. While agricultural pollution is largely unregulated, it is essential to be aware of regions with high farmland and nutrient concentrations, as surrounding rivers and lakes are at high risk of pollution. China, India, Brazil, the United States, and Pakistan are among the top contributors to excess phosphorus pollution. Additionally, Asian countries, including India, have traditionally used animal and human excreta as organic fertilizer, further exacerbating water pollution issues.

The US has the most corn-producing states, with Iowa, Illinois, Nebraska, and Minnesota supplying 32% of corn globally

The US is the world's largest producer of corn, with 96,000,000 acres (39,000,000 hectares) of land reserved for corn production. The US produced 14.9 billion bushels of corn in 2024, down from 15.3 billion bushels in 2023. Iowa, Illinois, Nebraska, and Minnesota are the top corn-producing states, accounting for more than half of the corn growth in the US and 32% of corn globally. Iowa is the largest producer of corn in the US, with 918 times more corn production than West Virginia, which ranks 41st in US corn production by state. In 2011, Iowa had 92,300 corn farms on 30,700,000 acres (12,400,000 hectares), with an average size of 333 acres (135 hectares) and an average dollar value per acre of $6,708. In the same year, there were 13.7 million harvested acres of corn for grain, producing 2.36 billion bushels, yielding 172 bu/acre, with a corn production value of $14.5 billion. Nebraska is the third-largest corn-producing state in the US and is known as the "Cornhusker State". Corn is Minnesota's largest crop.

While corn production is essential to the US economy, it is important to consider the environmental impact of fertilizer use. Overuse of fertilizers has led to increased nitrate levels in water supplies, affecting rural areas in particular. This has resulted in health issues such as high birth defect rates and an increased risk of colon cancer. The cost of clean water is also impacted, with rural residents bearing higher costs for filtering nitrates from their water.

China is the largest polluter, producing one-third of the world's excess phosphorus

Water pollution by fertilizers is a pressing issue, with rising nitrate levels in water supplies affecting many regions. While several countries contribute to this problem, China stands out as the largest polluter, playing a significant role in phosphorus pollution worldwide.

China's role in global phosphorus pollution is substantial, with the country contributing 30% of the freshwater phosphorus load, according to a study published in the American Geophysical Union journal Water Resources Research. This study, which examined data from 2002 to 2010, revealed that human activity released approximately 1.47 teragrams (1.62 million US tons) of phosphorus into freshwater bodies annually, with China being the leading emitter.

The excessive use of fertilizers in China has led to large anthropogenic phosphorus inputs, resulting in widespread eutrophication of water bodies. Eutrophication, caused by high phosphorus levels, leads to algal blooms, which have detrimental effects on aquatic ecosystems and reduce the usability of water for human activities.

China's significant contribution to phosphorus pollution is concerning, given that phosphorus is considered a long-term pollutant by some researchers. The generous application of phosphorus-containing fertilizers in agriculture has resulted in excess phosphorus washing into rivers, lakes, and coastal areas, compromising water quality and threatening environmental sustainability and food security.

To address this issue, China has taken initiatives to transition to cleaner energy sources and promote sustainable practices. As the global leader in renewable energy deployment, China aims to double its wind and solar energy production by 2025. Additionally, the country has recognized the importance of collaboration with other major exporters to jointly tackle the challenges of producing cleaner phosphorus fertilizers.

Singapore, New Zealand, Japan, South Korea, and Belgium are also near the top of the list

New Zealand, similarly, faces challenges in maintaining water quality due to agricultural activities and pollution from human settlements. While specific details on water pollution in New Zealand are scarce, it is safe to assume that similar issues regarding fertilizer use and water resource management are present.

Japan, like many other industrialized nations, struggles with water pollution from various sources, including agricultural runoff and industrial waste. The country has made significant strides in managing its water resources and treating wastewater, but the high population density and economic activities continue to strain water bodies and contribute to pollution.

South Korea, too, has experienced water quality degradation, particularly in its river basins, which serve as the primary water source for human activities. The heavy use of chemical fertilizers, insecticides, and pesticides in agriculture has accelerated water pollution problems. Additionally, population and industrial growth have placed increased pressure on limited water resources, leading to conflicts over water rights between regions. South Korea has undertaken various water policy reforms and invested in water pollution treatment facilities, but challenges remain.

Belgium, on the other hand, has been identified as having the highest levels of PFAS (per- and polyfluoroalkyl substances) chemical pollution in Europe. These "forever chemicals" build up in the body and the environment and have been linked to various health issues. High concentrations of PFAS have been found in groundwater near industrial sites, leading to concerns about their presence in the human food web. While Belgium and other European countries work towards regulating and reducing PFAS pollution, it remains a significant issue.

Excess phosphorus and nitrate run off fields into streams, rivers, and lakes, or seep into groundwater

Excessive phosphorus and nitrate runoff from fields into streams, rivers, and lakes or seeping into groundwater is a significant environmental concern. This issue is primarily caused by the overuse of fertilizers in agriculture, which has been increasingly prevalent over the past 40 years. The overapplication of fertilizers provides an abundance of nutrients to crops, which can then run off into nearby water sources. This is particularly common in regions with large amounts of farmland, such as the United States, China, India, Brazil, and Pakistan.

Phosphorus and nitrate are two of the most important and abundant nutrients applied to crops through fertilizers. While these nutrients are essential for crop growth, they can become pollutants when overapplied. When fields are over-fertilized, the excess phosphorus and nitrate can be washed away from the fields during rain or snowmelt, eventually making their way into nearby waterways. This process is known as fertilizer runoff. Additionally, these excess nutrients can seep into the soil and gradually make their way into groundwater, contaminating drinking water sources.

The impact of this pollution can be seen in the degradation of water quality and the disruption of aquatic ecosystems. High levels of phosphorus and nitrate in water can cause a process called eutrophication, where excessive growth of aquatic plants and algae occurs. This overgrowth can lead to the formation of unsightly scum on the water surface, clogging water intake pipes and reducing recreational value. As the algae decompose, they consume dissolved oxygen, which can lead to fish kills and a decrease in overall aquatic life, affecting fishing, swimming, and boating activities.

Furthermore, the contamination of groundwater can have significant health implications. Excessive nitrate levels in drinking water can pose risks, especially to young infants and livestock. Additionally, ammonia, another form of nitrogen found in natural waters, can be toxic to fish and, if consumed, can be harmful to humans as well.

To address this issue, several measures can be implemented. Firstly, reducing the amount of fertilizer used on fields is crucial. Farmers can also engage in watershed efforts by collaborating with various organizations and community groups to reduce nutrient pollution. Implementing conservation drainage practices, such as modifying drainage systems and utilizing cover crops, can help manage water movement and prevent nutrient loss into waterways. Ensuring year-round ground cover and planting field buffers, such as trees and shrubs, can also aid in minimizing erosion and nutrient runoff.

There is no legislation limiting how much fertilizer farmers use on their cropland

The overuse of fertilizers has led to a significant increase in nitrates in water supplies, with rural areas being the most affected. This has resulted in adverse health effects, including high birth defect rates and an increased risk of colon cancer. Despite these concerns, there is currently no legislation in place that directly limits the amount of fertilizer that farmers can use on their cropland.

While some countries have implemented regulations to control nutrient runoff and reduce water pollution, these measures do not specifically restrict the quantity of fertilizer applied to cropland. For example, in Lithuania, the discharge of pig wastes from intensive pig farming has been identified as a major source of surface water pollution. Similarly, in Italy, the Po River has experienced similar issues with fertilizer runoff. In response, the FAO/ECE has reported on the environmental impacts of animal husbandry, which include the fertilization of surface waters due to direct discharges of manure.

In the United States, there has been a debate about whether the government should restrict fertilizer use to improve water quality. Lake Erie, for instance, has been affected by toxic blooms, leading to concerns about the pollution of drinking water in Toledo, Ohio. However, no specific legislation has been mentioned or implemented to directly limit fertilizer use on cropland.

The lack of legislation limiting fertilizer use can be attributed to several factors. Firstly, fertilizers have brought significant socioeconomic and developmental benefits, such as improved crop yields and reduced land destruction. Secondly, the alternative options for nutrient control, such as incineration and landfill, come with their own set of challenges and costs. For example, sludge, which is considered an organic fertilizer, often contains unacceptable levels of heavy metals.

Additionally, there is a dilemma in many countries regarding the relative contributions of agriculture and untreated municipal sewage to water pollution. The lack of comprehensive databases makes it difficult to distinguish between these sources, hindering the development of effective pollution abatement programs and cost-efficient control measures.

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