Soil is the basis for life as we know it. After all, 95% of the food we eat comes from our soils. Thankfully, livestock producers have always known this, and now consumers are becoming increasingly aware of the importance of soil health.
The UN has warned us that the world’s soils are becoming exhausted. So depleted of nutrients that it is estimated that there are only 60 harvests left before our planet’s soils are too degraded to even support food production.
Soil supports life, and today, on World Water Day, it’s important to recognize that water is an essential component of soil health. The problem is that our soils have become so depleted that the soil simply can’t soak up water like it once did. Instead, water rushes off, leaving creeks and aquifers depleted, and contributing to water quality problems. The good news is that the spongy, thirsty soil can be brought back to life.
Soil scientists report that for every 1 percent of organic matter content, the soil can hold 16,500 gallons of plant-available water per acre of soil down to one foot deep. That is roughly 1.5 quarts of water per cubic foot of soil for each percent of organic matter. Increasing the organic matter content from 1 to 2 percent would increase the volume of water to 3 quarts per cubic foot of soil. One particular study also found that 1 pound of carbon can hold up to 40 pounds of water. In another study, it was found that increasing the water holding capacity of the soil by adding compost helped all crops during summer droughts by reducing periods of water stress.
The fact is that organic matter holds a lot of water, and the amount of organic matter in a soil directly influences the availability of water to a crop over time.
Not only are healthy soils necessary to grow food, we need them to produce enough food to meet the growing demands of the largest population that has ever lived on our planet. Farmers need to achieve maximum efficiency and the only way that this is possible is with healthy soils.
Not surprisingly, the rates of nutrients found in the soil will affect the quality of the yield. Soil that is low in nutrients, will be, as a result, inefficient at growing healthy crops, so for centuries, farmers have turned to fertilizer. But just like not enough of something isn’t good, too much isn’t good either!
Excessive use of chemical fertilizers can lead to soil salinity, heavy metal accumulation, water eutrophication and the accumulation of nitrates which can lead to air pollution. Chemical fertilizers contain mineral salts that plant roots can absorb quickly, but these salts do not provide a food source for soil microorganisms. Over time, soil structure declines and so does its water holding capacity.
This is where the true value of manure comes in. When managed properly, manure can transform soil health and regenerate the fertility of a farmer’s fields with limited environmental and social risks.
Animal manure is a true soil “builder” because of its ability to improve soil quality. Compared to chemical fertilizers, manure properly applied to land has the potential to:
- Increase soil carbon and micronutrient levels
- Reduce soil erosion and runoff
- Reduce nitrate leaching
- Increase crop yields
Used as a natural fertilizer and soil conditioner, the micro-nutrients and micro-organisms that are essential to make soil healthy are found in treated manure. Healthy soils act as natural protectants of our groundwater supply, filtering out contaminants. Manure enzymes also increase bacteria and fungi and microbial activity, which is crucial to soil nutrient cycling and the decomposition of organic matter. Together, microbes and enzymes control the soil’s nutrient availability and organic matter quality and quantity. The microbes found in manure also decrease the abundance of harmful organisms, such as disease-causing pathogens and plant pests.
“The proper use of manure reduces our reliance on commercially mined fertilizers that often have to travel great distances. Ultimately, thoughtful manure use leads to healthier soils, increased yields, and improved economics.” Newtrient
Tune in next week when we talk about how healthy soils can increase crop productivity while decreasing feed crop costs.