By Kaitlyn Ersek on Feb 9, 2023 10:00:00 AM
“Soil is a living, breathing entity that is teaming with life,” explains Dave Stark, Ph.D., Holganix President of Agriculture. “When soil is rich, healthy, and functional, it fosters healthier plants, better nutrient use efficiency, and greater crop yields. When soil health is poor, we see a need for greater inputs, loss in crop yield and quality.” As populations increase, soil health is key to meeting global food demand.
Yet, we are running out of healthy soil. The Food and Agriculture Organization (FAO) of the United Nations announced a warning in 2022 that 90% of the Earth’s topsoil would be at risk by 2050. In fact, “There are places that have already lost all of their topsoil,” explains Jo Handelsman, author of “A World Without Soil,” and a professor at the University of Wisconsin-Madison in an interview with CNBC.
In this blog, we discuss the top 10 threats to soil health, as named by the FAO. Click on the link below to skip to a soil threat or soil health solution that interests you, or keep scrolling to read the entirety of the article.
- Soil Erosion
- Soil Organic Carbon Loss
- Soil Nutrient Imbalance
- Soil Salinization
- Soil Contamination
- Soil Acidification
- Loss of Soil Biodiversity
- Soil Sealing
- Soil Compaction
- How Holganix Bio 800+ Builds Soil Health
“We have identified 10 soil threats in our global report … Soil erosion is number one because it’s taking place everywhere,” Ronald Vargas, the secretary of the Global Soil Partnership and Land and Water Officer at the Food and Agriculture Organization of the United Nations, told CNBC.
In fact, according to the UN, soil erosion may reduce up to 10% of global crop yields by 2050. That crop loss is equivalent to removing millions of acres of farmland.
Soil erosion is the loss of valuable topsoil through water, wind, tillage, or other means. Topsoil is the layer of soil that contains the most organic matter and is the most fertile. It supports the growth of plants, which in turn provide habitat and food for other organisms. When topsoil is eroded, the soil becomes less fertile and less able to support plant growth, which can lead to the decline of ecosystems and decreased agricultural productivity.
Erosion also contributes to the decline of soil health by removing essential nutrients and minerals from the soil, making it more difficult for plants to take up the nutrients they need to grow. The loss of topsoil also increases the risk of soil degradation and contamination, as the protective layer that covers the subsoil is lost. This can result in increased runoff and the loss of valuable water resources.
A new report out of the University of Massachusetts Amherst indicated that topsoil in parts of the American Midwest is experiencing erosion levels 1,000 times the natural rate of erosion. The study measured the elevation differences between native prairie and farm fields to see how tilling affected erosion. The report shows that 57.6 billion metric tons of Midwest topsoil have eroded over the last 160 years with the average field at 1.2 feet below the prairie.
Soil Organic Carbon Loss
Soil organic carbon loss refers to the reduction in the amount of organic carbon in the soil. Organic carbon is an essential component of soil, contributing to soil fertility, water-holding capacity, and overall health. Soil organic carbon is derived from plant and animal residues, which are decomposed by soil organisms into organic matter.
Soil organic carbon loss can occur for a variety of reasons, including:
- Agricultural practices - tillage, monoculture cropping systems, and the use of synthetic fertilizers can reduce soil organic carbon levels by altering the soil food web and reducing the input of organic matter.
- Land use change - converting natural ecosystems, such as forests and wetlands, to agricultural or urban use can result in a significant loss of soil organic carbon.
- Climate change - changes in temperature and precipitation patterns, as well as increased frequency of extreme weather events, can impact the rate of organic matter decomposition and soil organic carbon levels.
Soil organic carbon loss can have negative impacts on soil health, including:
- Reduced soil fertility - soil organic carbon is an essential component of soil fertility, providing essential nutrients for plant growth.
- Decreased water-holding capacity - soil organic carbon contributes to soil water-holding capacity, which is essential for plant growth.
- Increased greenhouse gas emissions - soil organic carbon is a large pool of carbon, and soil organic carbon loss can result in the release of carbon dioxide (CO2) and other greenhouse gases into the atmosphere, contributing to climate change.
Soil Nutrient Imbalance
Nutrient imbalance refers to an unequal distribution of essential nutrients in the soil, which can negatively impact plant growth and overall soil health. Essential plant nutrients, such as nitrogen, phosphorus, and potassium, are needed in specific proportions to support healthy plant growth. When these nutrients are not in balance, it can lead to a variety of issues, including:
- Reduced plant growth - an imbalance of essential nutrients can limit plant growth, as the plant is unable to take up the necessary nutrients for growth.
- Soil acidification - an imbalance of essential nutrients can also result in soil acidification, which can reduce the availability of essential plant nutrients and reduce soil fertility.
- Changes in soil biota - an imbalance of essential nutrients can also affect the composition of soil biota, such as microorganisms and insects, which can disrupt the delicate balance of the soil food web and reduce soil health.
- Altered soil chemistry - an imbalance of essential nutrients can also alter soil chemistry, reducing the availability of essential plant nutrients and impacting soil health.
Nutrient imbalance can be caused by a variety of factors, including over-fertilization, imbalanced use of fertilizers, soil degradation, and loss of soil organic matter.
Soil salinization is the process by which soil becomes increasingly salty, leading to a decline in soil fertility and productivity. It occurs when salts in the soil accumulate to levels that are toxic to plants, altering the soil's physical, chemical, and biological properties.
The main causes of soil salinization are:
- Irrigation - Over-irrigation can lead to the buildup of salts in the soil, as the excess water carries dissolved salts into the root zone, where they can accumulate.
- Climate - Arid and semi-arid climates can also contribute to soil salinization, as high evaporation rates concentrate salts in the soil.
- Natural processes - Soil salinization can also occur as a result of natural processes, such as the weathering of rock minerals and the deposition of salts from the ocean.
The effects of soil salinization on soil health are significant, including:
- Reduced plant growth - Soil salinization can reduce the growth and productivity of crops and other plants, as the high salt concentration can be toxic to plant roots.
- Altered soil structure - Soil salinization can alter the physical structure of the soil, making it denser and more compact, and reducing the availability of air and water to the roots of plants.
- Decreased soil fertility - Soil salinization can also reduce the fertility of the soil, as the high salt concentration can interfere with the uptake of essential nutrients by plants.
- Altered soil biota - Soil salinization can also affect the composition of soil biota, such as microorganisms and insects, which can disrupt the delicate balance of the soil food web and reduce soil health.
Soil contamination introduces harmful substances into the soil that can harm plants, animals, and humans. Soil contamination can occur due to various sources, including:
- Agricultural practices - the use of pesticides, fertilizers, and other chemicals in agriculture can lead to soil contamination.
- Industrial activities - industries such as mining, manufacturing, and waste disposal can release toxic chemicals into the soil.
- Natural sources - soil can also become contaminated through natural processes, such as volcanic eruptions or leaching of minerals from rocks.
Soil contamination can have several negative impacts on soil health, including:
- Reduced plant growth - contaminated soil can contain harmful chemicals that can harm or kill plants, reducing overall productivity.
- Toxicity to animals - contaminated soil can be toxic to animals, including wildlife, domesticated animals, and even humans.
- Health risks to humans - contaminated soil can pose a risk to human health, particularly if the contaminants are ingested or inhaled.
- Decreased biodiversity - soil contamination can reduce the diversity of soil organisms and disrupt the soil food web, reducing the overall health of the soil ecosystem.
Soil acidification refers to the process by which soil pH decreases, becoming more acidic. Soil pH is a measure of soil acidity or alkalinity, with a pH range of 0 to 14, with 7 being neutral. Soils with a pH less than 7 are considered acidic, while soils with a pH greater than 7 are considered alkaline.
Soil acidification can occur naturally over time, but it can also be accelerated by human activities, such as the use of acidifying fertilizers, land use change, and soil degradation. Some of the effects of soil acidification include:
- Reduced availability of essential plant nutrients - soil acidification can reduce the availability of essential plant nutrients, such as calcium, magnesium, and phosphorus, which are essential for healthy plant growth.
- Altered soil biota - soil acidification can also affect the composition of soil biota, such as microorganisms and insects, which can disrupt the delicate balance of the soil food web and reduce soil health.
- Reduced plant growth - soil acidification can limit plant growth by reducing the availability of essential plant nutrients and altering soil biota.
- Increased metal toxicity - soil acidification can also increase the availability of toxic metals, such as aluminum and manganese, which can be toxic to plants and other soil biotas.
Loss of Soil Biodiversity
Loss of soil biodiversity can have a significant impact on soil health, as the health of soil ecosystems is closely tied to the diversity of soil biota, such as microorganisms, insects, and plants. Some of the ways in which loss of biodiversity can affect soil health include:
- Disrupting the soil food web - the loss of biodiversity can disrupt the delicate balance of the soil food web, reducing the ability of soil organisms to carry out important processes, such as nutrient cycling and decomposition.
- Decreased nutrient cycling - soil biota plays a critical role in nutrient cycling, breaking down organic matter and making essential nutrients available to plants. Loss of biodiversity can reduce the efficiency of nutrient cycling, reducing soil fertility and overall health.
- Increased vulnerability to soil degradation - soil ecosystems with high levels of biodiversity are typically more resilient to degradation and can recover more quickly from disturbances. Loss of biodiversity can make soil ecosystems more vulnerable to degradation and reduce their ability to recover from disturbances.
- Decreased soil carbon sequestration - soil biota, such as plants and microorganisms, play a critical role in soil carbon sequestration, which helps to mitigate climate change. Loss of biodiversity can reduce the efficiency of carbon sequestration, increasing the release of greenhouse gases into the atmosphere.
Soil sealing refers to the process by which the natural properties of the soil are altered through the application of a hard and impermeable surface layer, such as concrete, asphalt, or brick. This layer acts as a barrier, reducing the exchange of air, water, and nutrients between the soil and the atmosphere, and preventing the natural infiltration of water into the soil.
Soil sealing has several negative impacts on soil health, including:
- Reduced water infiltration - soil sealing reduces the ability of water to penetrate the soil, leading to increased runoff and reduced groundwater recharge.
- Altered soil temperature and moisture - soil sealing can also alter the soil temperature and moisture regime, making it more difficult for plants to grow and for soil biota to survive.
- Loss of biodiversity - soil sealing can also lead to the loss of biodiversity, as the hard surface layer eliminates or reduces the area of natural habitats for plants and animals and reduces the area of soil available for growth.
- Reduced soil organic matter - soil sealing can also reduce the accumulation of soil organic matter, as the hard surface layer prevents the entry of organic matter into the soil and reduces the decomposition of organic matter by soil biota.
- Increased heat island effect - soil sealing can also contribute to the heat island effect, as the hard surface layer absorbs and retains heat, leading to increased temperatures in urban areas and reduced air quality.
Soil compaction is a bad thing for soil health because it reduces the porosity and pore space of the soil, making it more difficult for roots to penetrate the soil and access essential water and nutrients. This can lead to several negative impacts on soil health, including:
- Reduced root growth - compacted soil makes it difficult for plant roots to penetrate and absorb water and nutrients, reducing plant growth and overall productivity.
- Decreased water infiltration - compacted soil has less pore space, making it more difficult for water to penetrate the soil and be absorbed by plant roots, leading to increased runoff and decreased water retention.
- Decreased nutrient availability - soil compaction can reduce the availability of nutrients for plant growth, as roots have more difficulty accessing them.
- Increased erosion - compacted soil is more prone to erosion, as it is less able to absorb and retain water.
Soil compaction can be caused by several factors, including the use of heavy machinery, overgrazing, and urbanization.
Waterlogging refers to the situation where the soil remains waterlogged, or flooded, for an extended period of time. It occurs when the rate of water entering the soil exceeds the rate at which water can drain out of the soil. This can lead to saturation of the soil and a buildup of water in the root zone, reducing the availability of oxygen to the roots of plants and creating a stressful environment for plants to grow in.
Water logging can have several negative impacts on soil health, including:
- Reduced plant growth - water logging can limit plant growth by reducing the availability of oxygen to the roots of plants, leading to root death and reduced plant growth.
- Increased soil salinity - water logging can also lead to increased soil salinity, as saltwater may penetrate the soil and become trapped, increasing the concentration of salts in the soil.
- Altered soil biota - water logging can affect the composition of soil biota, such as microorganisms and insects, which can disrupt the delicate balance of the soil food web and reduce soil health.
- Soil erosion - water logging can also increase the risk of soil erosion, as the waterlogged soil may become more susceptible to water-related erosion processes, such as overland flow and sheet erosion.
Holganix Bio 800+ Builds Soil Health
At Holganix, we believe in preserving and nourishing the water and soil so it can be passed down to future generations.
Our flagship product, Holganix Bio 800+, harnesses the power of over 800 soil microbes to turbo-charge soils. As a result, Holganix Bio 800+ products improve soil health in the long term while increasing crop yield and reducing the need for fertilizer and other inputs in the short term.
Want to learn more about Bio 800+? Watch the 4-minute video below, featuring Holganix President of Agriculture, Dave Stark, Ph.D., with a discussion of how Holganix Bio 800+ works. If you are reading this blog via email, click here to access the video.