It is an exciting time to be working on soil health in California. The development of the Healthy Soils Initiative and recent California Department of Food and Agriculture (CDFA) Healthy Soils Summit in Sacramento have shown a spotlight on the growing enthusiasm around this work. Of course, this focus on soil health is not unique to California. The United Nations General Assembly declared 2015 the “International Year of Soils,” a move which underscored the fact that researchers, producers, and community members across the globe are turning their attention to the importance of fostering healthy soils.
On February 14th, CalCAN attended a CDFA webinar featuring stakeholders involved in healthy soils work in California and the Netherlands called “Challenges and Opportunities for Soil Management in Climate Change Adaptation and Mitigation.” The event featured representatives of CDFA, UC Davis, Wageningen University, and the Netherlands Ministry of Economic Affairs, among others.
It was a wonderful opportunity to connect with the work going on to support soil health in the Netherlands and compare those efforts with the work happening here in California. While the efforts of those involved in the webinar were varied, all shared the goal of increasing adaptation of healthy soil management practices in agriculture.
Dr. William Horwath, Professor of Soil Biogeochemistry at UC Davis kicked off the conversation with a discussion of the potential of mitigating nitrous oxide emissions through micro-irrigation. His presentation centered around a comparison of the nitrous oxide emissions associated with tomato fields using Subsurface Drip Irrigation (SDI) and those using a flood irrigation approach. He reported a climate benefit of SDI systems compared with flood irrigation, and shared that 90% of the tomato industry has voluntarily shifted to an SDI system.
Horwath was followed by Dr. V.L. Mulder of Wageningen University in the Netherlands. Mulder’s recent work has focused on the diverse strategies needed and barriers to improving soil health across the globe. Mulder compared twenty regions across the globe in terms of their current soil carbon stock, carbon sequestration potential, and identified opportunities and barriers to improving soil for each region.
She highlighted Chile and Australia as an example of varying contexts under which efforts are being made to improve soil health. In Chile, there are limited areas dedicated to cropland, and most efforts are focused on peatland conservation. Australia, on the other hand, has already adopted best practices for soil management on much of the land, so is struggling with the question of what more can be done to improve soil health in the country.
Mulder argued that there is no “one size fits all strategy” for improving soil health, because the barriers to improvement vary so drastically from one region to another. She also asserted that the success of healthy soil initiatives will depend on buy-in from a diverse group of stakeholders including: farmers, landowners, scientists, marketers, and policymakers.
Like California, the government of the Netherlands is beginning to take tangible steps toward improving soil health. Dr. Annet Zweep of the Netherlands Ministry of Economic Affairs reported on her office’s efforts to create healthy soil policy for the region. Currently, the onus is on the farmers to implement best practices on their land, and the Netherlands government lacks concrete policy or recommendations on soil health. Zweep cited the importance of soil health in building a sustainable economy and aiding in climate change mitigation.
However, she also noted that the Netherlands needs additional research on soil and soil management, specifically in connection with climate change. Zweep is currently working to develop a cohesive policy on soil management and identify a method for accurately assessing soil health in the Netherlands.
An update on the Healthy Soil Initiative was provided by Dr. Geetika Joshi of CDFA. She highlighted the importance of soil health for preserving the productivity of agriculture in California, in which more than 400 different agricultural commodities are currently produced.
Joshi also mentioned the importance of being able to quantify climate benefit and carbon sequestration associated with adopting healthy soil practices. She reported that CDFA and ARB are currently looking to the COMET-Planner tool out of Colorado State University (CSU) as a promising tool for this purpose. Dr. Paustain, a CSU researcher who has helped develop the COMET tool, provided a brief overview of the tool which is currently being adapted in order to be more California-specific.
Winfried Rajimakers, of the company Yara, reported on nitrogen sensors available to farmers in the Netherlands and the potential of “precision farming” to increase the sustainability of agriculture in the country. Yara has created a nitrogen sensor to scan fields and help farmers discern exactly where to apply fertilizer. The goal of the tool is to help farmers avoid over application of fertilizer, and according to Rajimakers its use can lead to a 10% reduction in nitrogen input.
However, there has been very little implementation of nitrogen sensors in the Netherlands because of the tool’s high cost. In Rajimakers view, farmers mistakenly believe that the long-term benefits of adopting such a tool don’t justify the initial investment.
The event concluded with open discussion, which included the earlier speakers as well as other stakeholders from both regions, including Judith Redmond of Full Belly Farmers and Cynthia Cory of California Farm Bureau. Several key themes emerged from the conversation, including the importance of ensuring that farmers have the technical and financial support to implement healthy soil practices, and the need to educate farmers about the benefits of healthy soil management to their operations.
Representatives of the Netherlands noted that the country’s lack of something analogous to a University Extension office has forced farmers to rely on private businesses for information on best practices, instead of receiving such information from “independent knowledge brokers.”
CalCAN was delighted to attend this event and hear some recent updates coming out of the Netherlands on healthy soils. Implementation of the Healthy Soils Initiative continues in California, with the next meeting of the Environmental Farming Act Science Advisory Panel taking place on March 16th in Sacramento.