After intensive crop production, cattle are needed to save the earth

Manure improves soil and microbial community

We usually think of healthy soil as moist and loose with lots of organic matter. But if the land is in an arid climate, how quickly does the addition of manure take effect, and is it even beneficial?

These questions were answered by members of the American Soil Society who traveled to the drylands of Texas to test manure as a top dressing.

“We know that establishing perennial cattle pastures can help protect and restore soil in semi-arid lands that have been eroded and degraded by intensive farming,” says Lindsey Slaughter, Fellow of the American Society of Soil Science.

Slaughter describes soil HEALTH as the ability of a living soil ecosystem to perform many important functions. These include nutrient cycling, water storage and purification, helping plants and animals, and more.

This "living" part consists of various microorganisms involved in the matter. They break down the same manure, for example, so that it and the nutrients it contains become part of the soil.

“The addition of manure can provide more material to be incorporated into soil organic matter, creating a stronger foundation for more microbial activity and nutrient cycling,” explains Slaughter.

In their study, the scientists applied a small amount of manure to two types of plots: either grass that was fertilized occasionally, or a mixture of grass and legumes without fertilization.

Overall, they found that manure helps increase soil organic carbon and soil microbial counts, two important characteristics of healthy soil.

It took almost a year and a half to see the changes, although the researchers say this is not surprising.

“This tells us that even a small amount of added compost can take a long time to incorporate into the soil organic matter of semi-arid grasslands, but practice definitely helps,” Slaughter explains.

“We think that specifically here, due to the arid climate in the study area, where there is little annual rainfall, the microbial community could not work quickly and efficiently and was forced to decompose manure without water. However, we have received confirmation that microbes help to directly release nutrients from organic material in a form that plants can use, and also decompose these residues to create soil organic matter. And this is a way to improve farming systems,” she added.

The next steps in this work involve answering the question, would more manure or multiple applications be better? Will irrigation or nitrogen fertilizer additions speed up the process?

“We need more research for a strategy to rapidly improve soil health. This helps farmers save money on nutrients and supplements, conserves water and protects against soil degradation,” she concluded.