The land’s ability to grow and produce food and shelter for the earth’s human population is at risk. Wind and water erosion contribute to massive amounts of soil and land losses while weakening the soil’s chances of recovering.
Human population growth and agricultural practices are taking their toll on soil’s ability to rebound and recover from erosion events. Native vegetation removed from land exposes soil to the elements and weakens its structure by impeding microbe populations. Bare land limits the abundance of nutrients that are normally returned to the soil through decomposition.
Changes in temperature and precipitation affect soil health overall. Climate change plays a key role in weather events that create conditions for wind and water erosion. Because these conditions are primarily man-made, it will take man-made actions to reverse or minimize the damage.
What is Climate?
There can be some confusion when referring to climate, going so far as interchanging the words climate and weather. While weather relates to immediate or day-to-day conditions (it’s snowing, or a storm is brewing), climate refers to an overall state of being. Climate is a compilation of weather events over a period of time and can illuminate patterns and inspire predictions. Changes in climate affect the soil’s ecosystem through changes in precipitation, temperature increases, plant growth rates, and loss of nutrient intake and uptake.
Climate change refers to the acceleration of Earth’s natural cycles, how those changes impact weather events, and the planet’s overall health. Fossil fuel use, agriculture, and development all contribute to climate change and its effect on weather. As soil is compromised due to these changes in climate patterns and day-to-day weather cycles, its fertility is threatened, which in turn diminishes human efforts to grow food.
How Does Climate Affect Soil?
Climate changes are affecting both temperature and precipitation cycles. As temperatures increase, precipitation changes. One example is when rainfall replaces snowfall. To remain stable and productive, soil must retain certain levels of moisture depending on its region. Precipitation is more than the amount of water that drops onto the soil; it also relates to how quickly water evaporates and returns to the atmosphere. Temperature and precipitation can contribute to soil moisture. However, if the process of pulling water back out of the soil, referred to as ET, or evapotranspiration, isn’t taking place, pH levels and microbial activity might degrade.
Soil requires many actions to maintain its vitality. As each component is impacted, soil struggles to recover and continue production. Loss of available land is directly related to soil erosion. Human activity contributes to soil losses 10 times faster than the rate of loss through natural erosion processes. China and India see their soil loss at more than 30 times the normal erosion rate.
How Does Climate Change Affect Erosion?
Because wind and water events dictate soil erosion, it is apparent that climate change directly affects the prevalence of erosion. Fall and winter are traditionally the end of the harvesting season and signal the onset of the rainy season. Bare land is more vulnerable to erosion during this period, as its protections are compromised. Crop covers are lower or nonexistent, and soil is unable to stay in place and resist runoff.
The Pacific Northwest’s Regional Approaches to Climate Change (REACCH) annual report states that, ‘Although warming results in an increase in rain and a decrease in snow water equivalent into late winter, soil losses are tempered. We hypothesize that this is due to the early onset of biomass growth caused by warming,”
Although this statement might indicate that climate change can have its advantages, the swap of rainfall for snowfall is not an advantage. Additional rainfall means an increase in precipitation. As more rain than snow falls, and because snow is less dense, rain accumulates at a faster rate and heightens the conditions for soil erosion.
Soil and Climate Change
Soil is the basis for food and shelter, and the degradation of its health can lead to environmental, economic, and human health losses. Under current agricultural practices, tillage alone could increase the erosion rate from 0.17 tons per acre to 0.5 tons per acre, resulting in a 192% increase in soil loss.
Erosion leads to the devastating loss of topsoils as well as a weakening of the underlying subsoils. Acidity accumulates in soil and trickles down to ultimately affect the O horizon — soil’s parent layer.
Controlling Erosion in the Face of Climate Change
By altering farming practices and replanting protective vegetation, we might be able to minimize climate change effects on soil and erosion loss. The use of coir textiles that help soil retain water and maintain pH levels while diverting erosion’s path prove to reduce loss, as well. Taking care not to compact wet soil or let it dry out contributes to a healthy microbial colony that aids in soil’s nutrient uptake, distribution, and regeneration.
The Geography Department at University of Kentucky College of Arts and Sciences offers a hopeful scenario: “There’s an obvious warning here with respect to ongoing and future climate change — relatively minor climate-driven disturbances could result in disproportionately severe erosion and land degradation. But there’s also an opportunity — in some situations relatively minor climate-driven disturbances in areas already experiencing erosion or degradation could be tipped into a minimum erosion, non-degrading state.”
It is not too late to recognize the effects of climate change and soil erosion. Committing to practices that help reduce instances of erosion or working to avoid it in the first place can have a positive impact on the land that is still able to work in human favor. As conditions change for better or worse, human interaction might be the first line of defense to man-made situations.
When precautions are put into place and soil is given the chance to recover from previous seasons or harvests, the land might have an opportunity to bounce back and continue to produce. Stemming the effects of soil erosion is a crucial component for overall soil health and, ultimately, the health of the planet.