Soil degradation has become one of the most pressing global issues, because of its adverse effects on world food security, environment and quality of life (Eswaran et al., 2001). Farm management practices such as conventional tillage and monoculture cropping systems can directly damage soil health by causing erosion, carbon loss and nutrient depletion. Crop productivity will be compromised on degraded soil. For example, Schumacher et al. (1994) found relative yield loss for erosion class 3 averaged from 8 to 17 percent, when other effects such as land location and agronomic practices were controlled.
Role of producers in reversing soil degradation
Agricultural producers can play an active role in reversing soil degradation trends by adopting conservation practices, such as conservation tillage, diversified crop rotations, cover crops and livestock integration on crop lands to improve soil health through maintaining or increasing soil organic matter.
However, decision making is not always easy when it comes to adopting soil conservation practices. Besides soil health considerations, economic factors often plays a critical role in adoption decisions. In reality, the relationship between crop yields and soil quality is complex, and soil properties are not the only factor affecting crop yields. The use of advanced technology, new crop varieties and additional fertilizer inputs frequently mask the effects of soil erosion on yield (Eswaran et al., 2001). As a result, some producers may choose to use additional inputs, e.g., fertilizers, as substitutes for soil health investments. Furthermore, the length of time required to achieve soil health and profitability improvement will also influence the producers’ adoption decisions. Adoption rate for soil conservation practices will likely be low if most producers are either uncertain about profitability or believe it will take a long time to achieve economic benefits from soil health systems.
Linkage between soil health and economic profitability to be established
While the soil health benefits of conservation practices are often studied, very few studies have evaluated how soil health and economic returns will respond to conservation practice adoption. One exception was Karlen et al. (2013), which showed that net returns to land, labor, and management for no-till systems were greater than other tillage systems despite slightly lower yields. However, the connections between other soil health practices such as cover crops, diverse rotations and livestock integration on croplands and economic returns remain to be explored. In addition, the length of time it takes for different conservation practices to improve soil health and profitability hasn’t been studied yet. Another unknown is whether the effect of conservation practices vary by locations and precipitation gradients across years.
Goals of our ongoing project
There is a strong need to explore the linkage between soil health and economic returns. In addition, the impacts of conservation practices, such as no-till, cover crops, diversified crop rotation, and crop-livestock integrated management systems, on soil health and economic returns need to be quantified.
Our recently funded project through NRCS/USGS aims to identify short-term and long-term impacts of these soil conservation practices on soil health and economic returns. Specifically, the following relationship will be estimated: 1) adoption of soil health practices and change in soil indicators over time; 2) adoption of soil health practices and changes in yield, costs and profitability over time. To achieve these goals, we seek collaboration opportunities with producers who are interested to find out how their adoption of soil health practices have altered soil properties and economic profit over time, when compared to adjacent land where those practices are not adopted. For further information, please contact Jack Davis, Anthony Bly, or Tong Wang.
- Eswaran, H., R. Lal and P.F. Reich. 2001. Land degradation: an overview. In: Bridges, E.M., I.D. Hannam, L.R. Oldeman, F.W.T. Pening de Vries, S.J. Scherr, and S. Sompatpanit (eds.). Responses to Land Degradation. Proc. 2nd. International Conference on Land Degradation and Desertification, Khon Kaen, Thailand. Oxford Press, New Delhi, India.
- Karlen, D. L., Kovar, J. L., Cambardella, C. A., & Colvin, T. S. (2013). Thirty-year tillage effects on crop yield and soil fertility indicators. Soil & Tillage Research, 130, 24-41.
- Schumacher, T. E., Lindstrom, M. J., Mokma, D. L., & Nelson, W. W. (1994). Corn yield: erosion relationships of representative loess and till soils in the North Central United States. Journal of soil and water conservation, 49(1), 77-81.