The importance of maintaining our clean water in the face of climate change cannot be overstated. To accomplish this, it is crucial we understand the link between water quality and agriculture.
Organizations worldwide are exploring the impact different farming systems have on the environment, and it is clear that regenerative organic farming practices hold great promise in nurturing both healthy soils and clean water. Rodale Institute is at the forefront of this movement, conducting revolutionary research to demonstrate the vital connection between farming systems and water quality.
Regenerative organic farming systems differ significantly from conventional farming systems in many ways. For example, while conventional systems rely on synthetic inputs such as pesticides and nitrogen-based fertilizers, organic systems rely on carbon-based amendments such as animal and green manure to nourish the soil and optimize nutrient cycling. Rather than focusing solely on increasing crop productivity, regenerative organic farmers embrace a more holistic approach to prioritize soil health.
Healthy soils provide many agroecosystem services, including improving water quality (Zimnicki et al., 2020). A good indicator of healthy soil is high soil organic matter (SOM) content. Soil organic matter is the fraction of soil that consists of plant or animal tissue in varying stages of decomposition; typically, 58% of SOM is organic carbon (C). Soil rich in C or organic matter cycles and purifies water by acting as a filtration system for water as it flows into below-ground aquifers. It also plays a crucial role in watershed ecosystem services such as improving soil infiltration and reducing runoff and erosion. Agricultural soils with low SOM often erode quickly and can pollute waterways with high levels of synthetic fertilizers found in runoff (Rhoton et al., 2002). Improved infiltration rates can mitigate both drought and flood risk by facilitating water entry into the soil, storing moisture for times of drought, and preventing flash floods when rainfall happens more rapidly than infiltration can occur. An increase of only one percent of SOM can improve soil water holding capacity by 20,000 gallons per acre (Chou et al., 2015). In the face of climate change, which is characterized by frequent drought and excessive precipitation, soils high in organic matter are paramount in the success of adapting agricultural lands to changing environmental conditions.
How we manage our farmlands has a direct impact on soil organic matter content. Cover cropping and diversifying crop rotations are two key regenerative practices that are known to improve soil health over time. Cover cropping acts as a form of natural soil protection, reducing erosion and runoff. Longer and more diverse crop rotations are linked to improved overall soil fertility, decreasing the amount of nitrogen fertilizer needed for future crops (Lauer, 2010). It is well-documented that excess nitrogen reaches waterways in the form of runoff and overstimulates the growth of algae, often leaving dead-zones in ecosystems that can’t keep up with the accelerated growth (Cooperrider, et al. 2020; Mateo-Sagasta et al. 2018). These dead zones contaminate drinking water, posing a threat to both animals and humans. However, the implementation of regenerative practices such as cover cropping and diversifying crop rotations can help protect our access to clean water by helping to increase soil organic matter and therefore reducing both runoff and the need for excessive synthetic fertilizers.
In collaboration with the Stroud Water Research Center, Rodale Institute is spearheading a six-year-long groundbreaking study aimed at understanding the impact of different farming systems on water quality. This project consists of two trials – the Farming Systems Trial (FST), located at the Kutztown Rodale campus, and the Watershed Impact Trial (WIT), located at the Stroud Preserve in West Chester. Data collected from a previous study in FST reveals that long-term regenerative organic management practices significantly improve soil compaction and infiltration, reducing the risk of both flooding and runoff. Initial results from the ongoing trial provide valuable insights into the impact of different management practices on soil health and water quality. The higher soil organic matter content found in organic systems reduces the risk of nitrogen leaching into groundwater. Additionally, surface soil water samples demonstrate lower concentrations of total nitrogen in organic systems compared to conventional systems, further suggesting that organic farming contributes to improved water quality. Rodale Institute will use the results from this critical trial to educate the public on the link between farming practices and clean water.
As we strive to build a more sustainable and resilient agricultural system, the importance of organic farming and its impact on water quality must be at the forefront of our discussion. By using regenerative organic practices, farmers are not only nourishing the soil but safeguarding our water resources. As Rodale Institute continues to champion regenerative organic agriculture and conduct trailblazing research, the evidence is clear: regenerative organic farming practices, with their emphasis on building soil health, offer a promising solution for a more resilient and ecologically responsible food system. By supporting and adopting organic practices, we can pave the way towards a future where agriculture and water resources harmoniously coexist, ensuring the health of our ecosystems for generations to come.
References
Chou, B., O’Connor, C., & Bryant, L. (2015). Climate-Ready Soil: How Cover Crops Can Make Farms More Resilient to Extreme Weather Risks. NRDC, November Issue Brief.
Cooperrider, M.C., Davenport, L., Goodwin, S., Ryden, L., Way, N., Korstad, J. (2020). Case Studies on Cultural Eutrophication on Watersheds Around Lakes that Contribute to Toxic Blue-Green Algal Blooms. In: Bauddh, K., Kumar, S., Singh, R., Korstad, J. (eds) Ecological and Practical Applications for Sustainable Agriculture. Springer, Singapore. https://doi.org/10.1007/978-981-15-3372-3_16
Lauer, J. (2010). The natural benefits of crop rotations and the costs of monocultures.University of Wisconsin-Madison.
Mateo-Sagasta, J. ; Marjani Zadeh, S. ; Turral, H. (2018). More people, more food… worse water? – Water Pollution from Agriculture: a global review. Food and Agricultural Organization of the United Nations (68-72). ISBN 978-92-5-130729-8
Rhoton, F. E., Shipitalo, M. J., & Lindbo, D. (2002). Runoff and soil loss from midwestern and southeastern US silt loam soils as affected by tillage practice and soil organic matter content. Soil & Tillage Research, 66(1), 1–11. https://doi.org/10.1016/s0167-1987(02)00005-3
Zimnicki, T., Boring, T., Evenson, G., Kalcic, M., Karlen, D. L., Wilson, R. S., Zhang, Y., & Blesh, J. (2020). On quantifying water quality benefits of healthy soils. BioScience, 70(4), 343-352.
