Losing Phosphorus-Full

Phosphorus is an essential element for life, but its mining for fertilizers is causing environmental problems. Phosphorus is a limiting nutrient needed for plant growth, but excess runoff leads to algal blooms and dead zones in water bodies. Mining phosphorus-rich rock is non-renewable and produces waste and contaminants. Possible solutions include using fertilizers more efficiently, finding new mining locations, reducing mining waste, and recycling phosphorus from wastewater and food waste. Collaboration is needed to establish a sustainable phosphorus system for the future. There are many well-known elements that are essential for life such as carbon, oxygen, and nitrogen. One that is not mentioned as often but is equally as important is phosphorus. This element makes up important parts of every living organism including our cell walls, the energy our cells use, and even our DNA. Phosphorus follows a natural cycle that resembles a complex web. Initially stored in millions-year-old sedimentary rock, it undergoes weathering, releasing phosphorus into surface water and soils. Subsequently, soils and waters serve as reservoirs for phosphorus, facilitating its uptake by plants and microorganisms. This essential element is then transferred to animals or humans through consumption. Eventually, this phosphorus is excreted as waste, contributing to the formation of new rock over the course of another million years. In most ecosystem, Nitrogen and phosphorus are what's called limiting nutrients, meaning they are the most needed for growth within the ecosystem, and even small inputs of them can mean huge increases in growth. As humans turned to agriculture, they discovered the importance of this limiting nutrient and began applying naturally occurring sources of phosphorus, such as animal waste, to their fields to get better and healthier crops. This was a closed-loop system, allowing for fertilizers to be renewable and self-sufficient. As our population grew, people needed to find a larger and more industrial source of phosphorus to keep up with food demand. Today, we have turned to non-renewable mining of phosphorus-rich rock, termed phosphorite, into fertilizers. This process involves using concentrated acids to turn the rock into a form that plants can use. This process creates five tons of waste for every one ton of usable fertilizer, mostly in the form of useless and radioactive phosphogypsum. It also produces countless heavy metals and other contaminants that are naturally found in the rock already, like lead, uranium, and mercury. These rocks take millions of years to form naturally, making this process highly non-renewable, meaning once that rock is gone, we will not get any more, and the mining of this rock has only been increasing. An analysis of phosphate rock mining in 2010 predicted that we will reach our peak rock mining between 2030 and 2100. This worries scientists who look at the growth of the human population and the food required to feed them. If the mining of this rock can't keep up with food demand, widespread food shortages and agricultural collapse could be in our future. Even once the phosphorus is put on fields and into animal feed, not all of it will get absorbed. When there is excess phosphorus in the soils and a heavy rain comes, much of that phosphorus is swept away as runoff and ends up in unwanted areas, such as lakes, rivers, or oceans. This huge spike in a limiting nutrient causes large colonies of unicellular organisms called algae to grow rapidly. This turns water into a slimy green mess, and once that algae dies and their cells decompose, all of the oxygen is depleted in the water, which can choke out local marine life. This causes massive dead zones, such as the one in the Gulf of Mexico, where very little can survive. This kills fish, coral, and other marine life. As runoff has continued, the Gulf of Mexico's dead zone has only increased in size and currently spans over 5,000 square miles. In addition, according to a study published by Nature, researchers found the frequency of algal blooms increased by 60 percent between the years 2003 and 2020. There are a couple of other places besides agricultural fields where the careless loss of phosphorus could be stopped. According to another study by Wei-Feng Zhang at the Agricultural University of China, mining itself can waste around 40 percent of the phosphorus in the rock due to inefficient refining methods. In addition, we lose an incredible amount of phosphorus in our livestock production systems and in food waste. This causes phosphorus to sit in landfills unused or be literally flushed away as waste. All of this waste may make the future look bleak, but there are possible solutions that could allow us to harness this wasted phosphorus and make sure that we have enough food to last many more generations. According to MIT, there are a couple of different routes we can take. First, we can be smarter about the usage of phosphorus fertilizers. Many labs are trying to create plants that require less phosphorus or can uptake that nutrient faster by selectively breeding for more efficient plants. Making sure not to over apply fertilizer can also reduce runoff and make sure that plants only get what they can uptake without that excess. Secondly, new mining locations can be found or mining can be done better. Because phosphorite is rock, we can scout out new deposits in areas like Morocco or the Western Sahara that have large deposits already found and possibly more waiting to be discovered. These reserves can be found and protected, allowing for them to be used in the future when other areas have run out. Also, making sure that that 40 percent of mining waste mentioned earlier is reduced by making refining more efficient could help as well. Lastly, we can try to recycle the phosphorus already being lost in runoff or waste. There are methods of water treatment being researched that can take phosphorus out of wastewater and put it back into a usable fertilizer. Creating bio fertilizers out of food waste or those algal blooms is also being researched in order to minimize waste. Most recycling systems are still in the early stages, but focusing on their development could allow humanity to return to a more sustainable and closed-loop system once again. Altogether, none of these solutions are one and done. We need to work together in a combined effort to make sure that there is a sustainable phosphorus system in place for the future and that no one runs out of food in the years to come.