SOIL ORGANIC MATTER: THE KEY TO SOIL HEALTH, CLIMATE SMART AGRICULTURE, AND RESILIENT LANDSCAPES

• Sponsoring Institution: National Institute of Food and Agriculture
• Project Status: REVISED
• Funding Source: HATCH
• Reporting Frequency: Annual
• Accession No.: 1021472
• Project No.: HAW01151-H
• Project Start Date: Dec 5, 2019
• Project End Date: Sep 30, 2024

Project Director
Crow, SU, E..

Recipient Organization
UNIV OF HAWAII
3190 MAILE WAY
HONOLULU,HI 96822

Performing Department
Natural Resources & Environmental Management

Non Technical Summary
Climate change, induced predominantly by fossil fuel consumption and deforestation for intensive agricultural production, is an immediate threat to Hawaii and our communities and requires action from every sector. Although small in size, Hawaii must do our part to reduce carbon and other greenhouse gas (GHG) emissions while also building resilience into our landscapes and communities in order to adapt to the changing environment. As sectors with major sources of emissions, such as energy and transportation, are tackled in the coming decade, land-based climate actions must also begin immediately to improve their own GHG balance, and ultimately sequester enough carbon to offset residual non-renewable emissions within the new carbon economy. Multiple policy goals must be met in the coming decades, including increased local food production, 100% renewable energy, carbon neutrality, and improved soil health and carbon sequestration in natural and working lands, all of which require physical space in our landscape to achieve. For lands remaining productive, whether in protected forests, agroforests, rangeland, and cropping systems, soil health is a unifying principle. We will define soil health and develop a soil health index for Hawaii, measure and monitor soil health with partners changing management and land use on the landscape, initialize and improve available agroecosystem models, build a web-based tool, and effectively communicate the potential value of actuating land-based soil health and climate smart practices, with particular emphasis on the vast array of co-benefits that healthy, resilient soils bring to communities. With an increased knowledge base, recommendations and training for land use and practices to increase carbon drawdown, i.e., transfer from the atmosphere to long-term storage reservoirs, can be developed. The outputs will be quantitative, science-based decision support and policy tools that will help implement legislation and incentivize good practices for all land managers and producers. To actuate means to make something work, synonyms include activate, switch on, trigger, set in motion, initialize, energize, motivate, stimulate, drive, fire up. The ultimate goal, or outcome, of the proposed work is actuating land-based soil health and climate smart practices, with particular emphasis on the vast array of co-benefits that healthy, resilient soils bring to society.

Animal Health Component

0%

Research Effort Categories

Basic

25%

Applied

25%

Developmental

50%

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
101	0199	1070	50%
102	0199	1070	50%

Knowledge Area
102 - Soil, Plant, Water, Nutrient Relationships; 101 - Appraisal of Soil Resources;

Subject Of Investigation
0199 - Soil and land, general;

Field Of Science
1070 - Ecology;

Keywords

climate change

soil health

agroecosystems

resilience

land use

Goals / Objectives
Climate change, induced predominantly by fossil fuel consumption and deforestation for intensive agricultural production, is an immediate threat to Hawaii and our communities and requires action from every sector. Although small in size, Hawaii must do our part to reduce carbon and other greenhouse gas (GHG) emissions while also building resilience into our landscapes and communities in order to adapt to the changing environment. As sectors with major sources of emissions, such as energy and transportation, are tackled in the coming decade, land-based climate actions must also begin immediately to improve their own GHG balance, and ultimately sequester enough carbon to offset residual non-renewable emissions within the new carbon economy. Multiple policy goals must be met in the coming decades, including increased local food production, 100% renewable energy, carbon neutrality, and improved soil health and carbon sequestration in natural and working lands, all of which require physical space in our landscape to achieve. For lands remaining productive, whether in protected forests, agroforests, rangeland, and cropping systems, soil health is a unifying principle.Specific objectives are as follows: 1) Communicate a definition of soil health for Hawaii and describe why it is important and how to achieve it. Specifically, practices that support the principles of adaptive soil health management systems across the range of productive systems in Hawaii. 2) Develop a soil health index from a set of parameters established to be indicators of healthy soil in Hawaii, applicable across a range of land uses, management, and soils. 3) Establish sites with partners to begin measurements and monitoring of soil health with land use or management change across critical soils and productive systems. 4) Initialize and improve available soil carbon and ecosystem models to serve as the basis for decision support and policy tools in Hawaii. 5) Build a web-based module for soil health and potential carbon sequestration specific to Hawaii in parallel with planned initialization of NRCS COMET Farm and Planner Tools. 6) Effectively communicate the potential value of actuating land-based soil health and climate smart practices, with particular emphasis on the vast array of co-benefits that healthy, resilient soils bring to communities.Recent work quantitatively derived a suite of soil health parameters appropriate for the diverse soils, environments, and productive systems present today in Hawaii. Yet, more work is required to derive a clear soil health index with appropriate scaling and benchmarks for Hawaii's agroecosystems. An index must be developed from Hawaii's systems for Hawaii's systems in order to ensure a fair and equitable system that will support all land managers and producers to improve the health of their soils and therefore the collective resilience of Hawaii's productive landscapes. Multiple proposed indicators of Hawaii soil health, across physical, chemical, and biological classifications, relate directly to soil functions that affect the carbon balance of Hawaii's systems. Thus, the proposed work also will improve our understanding of the capacity for the Hawaiian landscape to perform climate change mitigationWith an increased knowledge base, recommendations and training for land use and practices to increase carbon drawdown, i.e., transfer from the atmosphere to long-term storage reservoirs, can be developed. The outputs will be quantitative, science-based decision support and policy tools that will help implement legislation and incentivize good practices for all land managers and producers. To actuate means to make something work, synonyms include activate, switch on, trigger, set in motion, initialize, energize, motivate, stimulate, drive, fire up. The ultimate goal, or outcome, of the proposed work is actuating land-based soil health and climate smart practices, with particular emphasis on the vast array of co-benefits that healthy, resilient soils bring to communities.

Project Methods
General procedure for each objective.Definition of soil health for Hawaii:Previous quantitative research led by M.S. student Hannah Hubanks identified a suite of soil health parameters appropriate for Hawaii. These results are within a M.S. thesis (Hubanks, 2019) and will be vetted through the peer-review process to serve as the basis for defining soil health clearly and quantitatively for Hawaii. The values of the soil health parameters collected during previous work will be communicated back to partner land managers and farmers as soil health results to share information and get feedback on the concept, results interpretation, and reporting. A resulting extension publication using data from Hannah Hubanks' thesis and feedback from partners to demonstrate potential soil health in specific systems common in Hawaii will further define what soil health means for our land managers and producers across the islands.Soil health index:To transition from a suite of parameters to an index, a rating system for each parameter will be developed based on optimization of desired levels, e.g., more is not always better, as some parameters may have an optimal value. For many of the proposed indicators, the relationship to optimal values for plant production often are known, as are the values for undisturbed natural systems. The expected range of desired levels may be constrained with such previous work, and then further tested. A two-pronged approach will be taken that addresses both benchmarks and change over time.Measurements and monitoring:A critical component of refining the soil health index and developing decision support tools is the collection of a critical mass of data for use in analysis in the long-term. As described, key partnerships with farmers, land managers, and researchers already conducting on-farm, in field trials of management practices in systems of considerable interest in Hawaii will be formed to collect soil and measure the suite of soil health parameters over time. We will offer to continue soil testing over time to farmers and land managers that participated in previous soil health work.Soil carbon and ecosystem models:Complex soil processes such as root and microbial growth, death, and decomposition interact with the soil environment and minerals to determine the carbon balance of a system. Mathematical models help simplify the belowground system, while capturing the critical components that drive carbon dynamics and balance over time in order to help project potential climate benefits. Mathematical representations that simplify terrestrial systems while still maintaining integrity and incorporating key regulating processes are the bridge between the science and policy of carbon and land-based climate change mitigation. Without a model that accurately projects reasonable expectations for change in soil health and carbon sequestration, planners and policy makers cannot make decisions about entering into agreements that will facilitate the implementation of policies and verification of results.In search of the best understanding and representation of the diversity of Hawaii's terrestrial ecosystems, three modeling approaches for soil carbon stocks and dynamics will be compared for a set of 12 key study sites that were part of the original soil health study. First, a novel 3-pool kinetic model of belowground carbon flow in the absence of additional inputs as determined by long-term soil incubation will be developed using the SoilR package (Sierra, Müller, & Trumbore, 2012)(Sierra, Müller, & Trumbore, 2012)(Sierra et al., 2012)(Sierra et al., 2012). Additionally, a biogeochemical process model under development, such as MEMS v1.0 (Fig. 3) (Robertson et al., 2018), will be initialized to improve the representation of soil carbon belowground based on inputs and carbon flow through multiple measurable pools. At the same time, we will collaborate on the initialization of the ecosystem model DAYCENT for critical production systems in Hawaii by the research team at CSU. The soil carbon representation of each will be compared in order to identify the best model for use in Hawaii's diverse landscapes and consider compartmental and stochastic options for Hawaii's dynamic systems and incorporated into the web-based module described below.Web-based module:A web-based soil health and potential carbon sequestration module will interact with the COMET Farm and Planner tools currently under development for Hawaii in collaboration with CSU researchers and contractors. Specific Objectives of the module are to 1) Engage farmers using community-based participatory approaches to assess soil health status and carbon sequestration and to identify appropriate strategies to improve soil health and carbon sequestration potential. 2) Synthesize current data available for Hawaiian soil management and visualize the data in the web-based tool, 3) Develop a web-based planning tool to record, monitor, and guide land use decision-making for enhanced soil health and carbon sequestration.

Progress 12/05/19 to 09/30/20

Outputs
Target Audience:The target audiences during this reporting period included farmers, producers, land managers, students, researchers, extension agents, local business and sustainability leaders, institutions, and policy makers. We relied heavily on our diverse network of Hawaii's farmers, producers, and land managers across the entire range of natural and working lands on three islands for progress on our research and, in turn, provided knowledge, discourse, and data services. CTAHR extension agents also were invaluable resources. Other researchers and earth system modelers remain interested in climate change feedbacks with terrestrial systems and specifically managed agroecosystems. Government agencies such as NRCS and the University extension service providers use our results to advise agribusiness and sustainable management practices to land owners, managers, and farmers. PI Crow and Co-PI Deenik serve as CTAHR representatives in the State Greenhouse Gas Sequestration Task Force. Institutions and policy makers are reached through service on multiple local, state, and international working groups, including the City and County of Honolulu Resilience Office committee for Climate Change Mitigation, Hawaii State Planning Office's Greenhouse Gas Sequestration Task Force (formerly Carbon Farming Task Force), International Soil Carbon Network, and the North American Carbon Program's Carbon Cycle Science Interagency Working Group; Science Leadership Group. Changes/Problems:The COVID-19 reality hit our research group hard and we've undertaken a reassessment of the project. We continue to meet goals and achieve objectives, but the laboratory was shut down for an extended period so we shifted focus to our web-based objectives and planning outreach online rather than our field-based studies and in person field days. What opportunities for training and professional development has the project provided?Three graduate student received training: one student is in the M.S. program (female) and two students are in the Ph.D. program (one male, one female). Christine Tallamy Glazer, Research Technician and P.I. of the Soils and Ecosystems Lab continued to develop analytical skills in the area of soil health assessment How have the results been disseminated to communities of interest?PI Crow participated extensively in outreach and science communication opportunities through service on various working groups and task forces during this reporting period. For example: International Soil Carbon Network (Action Team co-Leader) Large Scale Assessment of soil carbon storage, stability, and susceptibility to disturbance. City & County of Honolulu Office of Climate Change, Sustainability & Resilience Island Exposure & Innovation, Climate Change Mitigation Working Group (member) - As a participating city in the international 100 Resilient Cities initiative, the City & County of Honolulu is conducting multiple phases of resilience strategy planning, including tackling climate change by reducing emissions. August 2018-present. Hawaii State Planning Office Greenhouse Gas Sequestration Task Force (Member) - Established by Act 15, SHL 2018, the Task Force is comprised of 15 members from State agencies, nonprofit sector, private associations, and a researcher and an extension agent from CTAHR. The broad purpose is to expand and make permanent the task force, align the energy and sequestration efforts with climate initiatives, and make recommendations to achieve carbon neutrality by 2045. August 2018-present. What do you plan to do during the next reporting period to accomplish the goals?The web-based decision support and planning tools are being refined and we will network with Colorado State University researchers and the NRCS to initialize established models and web-based carbon and GHG sequestration tools for Hawaii and develop novel Hawaii-specific carbon models and soil health tools for producers and decision makers. A series of outreach seminars are planned to begin rolling out the webtool and getting more feedback from our stakeholders across farming, ranching, and forester sectors.

Impacts
What was accomplished under these goals? From our team's recent survey of natural and working lands in Hawai'i, we deduced 11 key soil health indicators from 46 parameters that declined with long-term intensive cultivation and measured reductions in soil health and soil function tied to losses in soil organic matter (SOM) due to heavy-tillage and little to no return of organic matter. Significant, measurable improvements in soil health are possible through the adoption of practices that build soil health and restore degraded tropical soils include at least one of the following components: (1) increased C inputs through compost, cover cropping, or mulch, (2) agroforestry, and/or (3) the establishment and management of permanent ground cover. Natural and working lands in Hawai'i fall into several key categories that affect soil health. The primary land use classifications include identifying whether the land has an intensive agricultural history (i.e., sugarcane or pineapple, or other, plantation past). Then, whether the current land use falls into the broad categories of: protected forest, (native or non-native species dominated); agroforestry; pasture; unmanaged (could be grassland, shrubland, or forest); organic agriculture; conventional agriculture. How long since major land use transitions is also an important factor. Soil order, and major mineralogical classification (i.e., low activity clays, high activity clays, histic, or poorly and non-crystalline minerals) are also important factors in determining inherent levels of soil health and therefore the indexing of soil health to track change over time in Hawai'i. Soil health analyses were conducted at key sites with attributes that contribute to coverage of data resources across the range of natural and working lands in Hawai'i. The Hawai'i Soil Health Tool https://soilhealthhawaii.org is live and the outreach blog https://hawaiisoilhealth.weebly.com is active. We continue to work on refining the user interface and underlying database with our software engineers following feedback from extension agents. To maximize landscape-scale C sequestration rates, a Hawai'i team led by PI Crow were funded by the US Climate Alliance via American Forests, DLNR, and the State Energy Office to work with stakeholders and resource managers to develop a land-use classification map optimized for climate mitigation at the State of Hawai'i scale. We are currently seeking options for climate-smart landscapes that collaboratively identify and prioritize: 1) high-quality lands for climate-smart agriculture and ranching; 2) marginal lands for climate-smart reforestation, forestry, and agroforestry practices, 3) recently abandoned lands for rehabilitating soil health for agriculture, 4) managed forest, and 5) engages and honors the diverse conditions that shape land-use decision making in Hawai'i. In support of the legislatively formed Greenhouse Gas Sequestration Task Force, outcomes from that work will include a cross-sectoral land classification map and a first-order resource assessment to evaluate the implementation of C sequestration practices including impacts of policy and programs directed to achieving current legislative mandates. Critically, this is a bottom-up co-production process with diverse stakeholders that expands our network and reaches into the agricultural, natural resources, and biocultural restoration communities.

Publications

• Type: Journal Articles Status: Accepted Year Published: 2020 Citation: Crow, S.E., Wells, J.M., Sierra, C.A., Youkhana, A.H., Ogoshi, R.M., Richardson, D.T., Tallamy Glazer, C., Meki, M.N., and Kiniry, J.R. 2020. Carbon flow through energycane agroecosystems established post?intensive agriculture. Global Change Biology Bioenergy 12:806-817. https://doi.org/10.1111/gcbb.12713
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Lawrence, C.R., Beem-Miller, J., Hoyt, A.M., Monroe, G., Sierra, C.A., Stoner, S., Heckman, K., Blankinship, J.C., Crow, S.E., McNicol, G., Trumbore, S., Levine, P.A., Vinduakov�, O., Todd-Brown, K., Rasmussen, C., Hicks Pries, C.E., Sch�del, C., McFarlane, K., Doetterl, S., Hatt�, C., He, Y., Treat, C., Harden, J.W., Torn, M.S., Estop-Aragon�s, C., Asefaw Berhe, A., Keiluweit, M., Marin-Spiotta, E., Plante, A.F., Thomson, A., Schimel, J.P., Vaughn, L.J.S., and Wagai, R. 2020. An open source database for the synthesis of soil radiocarbon data: ISRaD version 1.0, Earth Syst. Sci. Data 12:61-76. https://doi.org/10.5194/essd-12-61-2020
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Sch�del, C., Beem-Miller, J., Aziz Rad, M., Crow, S.E., Hicks Pries, C., Ernakovich, J., Hoyt, A.M., Plante, A., Stoner, S., Treat, C.C., and Sierra, C.A. 2020. Decomposability of soil organic matter over time: The Soil Incubation Database (SIDb, version 1.0) and guidance for incubation procedures, Earth Syst. Sci. Data 12: 1511-1524. https://doi.org/10.5194/essd-12-1511-2020
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Yu, J.*, Deem, L.M.*, Crow, S.E., Deenik, J.L., and Penton, C.R. 2019. Comparative metagenomics reveals enhanced nutrient cycling potential after two years of biochar amendment in a tropical Oxisol. Applied and Environmental Microbiology 85:e02957-18. doi: 10.1128/AEM.02957-18
• Type: Conference Papers and Presentations Status: Accepted Year Published: 2020 Citation: Crow, S.E., Sierra, C.A., Cotrufo, M.F., and Harden, J.W. 2020. Networking soil carbon and health: a common ground for actuating resilience and climate change mitigation. North American Carbon Program Open Science Meeting 2020, Washington D.C., March 2020. (abstract accepted, COVID-19)
• Type: Conference Papers and Presentations Status: Accepted Year Published: 2020 Citation: Tallamy Glazer, C., Crow, S.E., Hubanks, H., Cotrufo, M.F., and Haddix, M. 2020. Mineral associated organic matter and soil health in Hawaii. Goldschmidt2020, Honolulu, HI, June 2020. (abstract accepted, COVID-19)
• Type: Conference Papers and Presentations Status: Accepted Year Published: 2020 Citation: Crow, S.E., McGrath, C., Hicks Pries, C.E., Nguyen, N., Lazaro, M., Giardina, C.P., and Litton, C.M. 2020. Complex non-crystalline mineralogy protects soil carbon from temperature-dependent decay. Goldschmidt2020, Honolulu, HI, June 2020. (abstract accepted, COVID-19)
• Type: Conference Papers and Presentations Status: Accepted Year Published: 2020 Citation: Sierra, C.A., Crow, S.E., Heimann, M., Metzler, H., and Schulze, E-D. 2020. The climate benefit of carbon sequestration. European Geophysical Union Meeting, Vienna, April 2020. (contributed abstract, accepted)
• Type: Conference Papers and Presentations Status: Accepted Year Published: 2019 Citation: Crow, S.E., Harden, J.W., and Sierra, C.A. 2019. Soil health and soil carbon: A common ground for actuating resilience and climate change mitigation. American Geophysical Union Annual Meeting, San Francisco, CA, December 2019. (contributed poster)