By Rajan Ghimere, PhD, NMSU and Isabelle Jenniches, NM Healthy Soil Working Group
The National Center on Carbon Management and Soil Health has been leading projects on regenerative approaches to improve soil health and enhance carbon storage in arid and semi-arid environments since 2023. Its main goal is to identify, verify and disseminate cost effective soil health and carbon management practices in all major land use types, i.e., croplands, rangelands, forests, and urban lands.
The Center consists of a network of sites across New Mexico: six NMSU Agricultural Science Centers (ASCs) serve as living laboratories, examining the viability and verifiability of carbon sequestration approaches for arid and semi-arid lands. In addition, several off- and on-campus crop, range, and turf-management sites demonstrate carbon sequestration practices unique to those regions.
At all locations connected to the center, researchers, stakeholders, and policymakers have the opportunity to examine carbon sequestration practices that provide financial incentives for farmers, ranchers, and landowners to harness changes in land management for climate change solutions.
Focus on Biochar as benefitting both the climate and soil health
Through grant funding from the Natural Resources Conservation Services, New Mexico Department of Agriculture, National Science Foundation, and the National Institute of Food and Agriculture, the center researchers are conducting multiple field, greenhouse, and laboratory studies on diverse aspects of carbon sequestration and soil health. One specific focus of these studies is to quantify biochar’s potential to enhance carbon storage, improve soil health, and reduce greenhouse gas (GHG) emissions in arid farming systems.
The center collaborates with researchers from Auburn University, the University of Delaware, and a few international partners for the biochar research. Within NMSU, the Center director Dr. Ghimire and affiliated faculty members Drs. John Idowu, Catie Brewer, Jinfa Zhang, and Xiufen (Sophia) Li have been characterizing biochar and testing its impacts on soil health, carbon storage, greenhouse gas emissions, and microbial community responses, and ultimately linking them to sustainable crop production in dry regions.
Cutting-edge technology, such as solar-powered LI-COR soil flux system with automated chambers, enables the researchers at the Clovis Science Center to continuously measure carbon dioxide (CO2), nitrous oxide (N2O), and methane (CH4) emissions in biochar and compost amended fields.
Complementary laboratory and greenhouse trials further explore how different types of modified biochar applications affect the cycling of carbon, nitrogen, and phosphorus in soil, and their role in regulating N2O emissions.
Three recently published studies highlight carbon sequestration approaches for dry regions and how biochar can reduce GHG emissions and store atmospheric carbon in soils while enhancing agricultural production.
Together, these interdisciplinary projects are charting a new path for agricultural and environmental sustainability in dryland regions, positioning biochar as a promising tool to enhance agricultural sustainability and resilience in hot, dry regions.
Estimating soil carbon sequestration and biological health in pecan orchards
Climate change and increased weather variability have affected crop production and soil health more seriously in arid and semiarid regions than in other areas. To cope with a hotter, drier and capricious climate in the southwestern United States, farmers have increasingly turned to crops with high market value and carbon (C) sequestration potential, for example pecans.
The United States is one of the world’s leading pecan producers. New Mexico is the second-largest producer in the country, accounting for nearly 35% of pecans grown in the US1 with more than 47,000 acres in production.
Pecans are planted in perennial orchard systems that can capture and store large amounts of atmospheric carbon dioxide (CO2) in woody biomass. CO2 is also transported through their extensive root systems to be stored in the soil.
In order to quantify the C sequestration potential of pecans in connection to soil health a recent study by Singh et al. (2025)2 evaluates the response of selected soil health indicators and C storage in pecan orchards of different ages (20, 40, and 80 years). A nearby cotton field was sampled as a control.
The study found that soil carbon accounts for over 70% of the total carbon sink in orchard ecosystems. While the relative impact varies depending on crop type, management practices and tree age, orchard care focused on soil health management approaches presents a nature-based solution to climate change in arid and semiarid regions by helping to mitigate greenhouse gas emissions.
Pecan orchards in New Mexico have been established since the early 1900s on lands used for row cropping systems. Much focus has been on how to improve yield in pecans, while much less attention has been paid to soil health in orchards.
The researchers found that rapid improvements in soil health is observed in the first 20 years of orchard establishment. Positive responses are especially noticeable in soil health indicators such as organic matter, microbial activity, and aggregate stability, with microbial activity and soil organic matter improving continuously as the orchard matures, which peaks in about 35-40 years. To maintain orchard productivity and enhance C sequestration beyond 40 years, regenerative practices, including amendment of soil with biochar could help. The centre researchers converted pecan waste and pruning byproduct to biochar and evaluated their potential to sequester carbon in a complementary study.
Biochar increases soil carbon storage and agricultural sustainability
Biochar has been increasingly promoted for use in sustainable and regenerative agriculture. Biochar prepared from farmland waste, such as orchard prunings or animal manure, has the potential to improve soil health, increase soil carbon storage, reduce GHG emissions, and resolve waste disposal issues, leading to agricultural sustainability and development of circular farm economy.
A study by Sapkota et al. (2025)3 shows that biochar can be prepared from farm wastes such as pecan shells, branches after pruning, and leaves, and reutilized in orchards to increase carbon storage. It can make a significant contribution to carbon storage, soil health, and sustainable crop production. In their study, pecan wood biochar increased soil organic carbon by 72% and significantly improved the stability of soil carbon, while manure biochar considerably improved soil phosphorus, magnesium, and other nutrients to support crop production.
These findings show that plant residue biochar is more effective for carbon storage and stability, while manure biochar enhances soil fertility and crop yield.
Use of biochar as soil amendment can reduce N2O emissions
Biochar application to soil also mitigates climate change by reducing greenhouse gas (GHG) emissions. Yet, significant uncertainty exists in quantifying the potential of biochar amendment to reduce soil nitrous oxide (N2O) emissions.
N2O is an important greenhouse gas that has a global warming potential 273 times greater than that of carbon dioxide over a 100-year time scale. About 60% of the global anthropogenic N2O emissions come from agriculture, primarily due to synthetic fertilizer and manure application. Release of N2O occurs during nitrogen transformation as a result of different biological and chemical processes in the soil.
Even modest reductions in N2O emissions from the soil by changing soil management could significantly reduce net GHG emissions while improving agricultural production.
A study by Sharma et al. (2025)4 evaluates soil N2O emissions from soils amended with biochar made from various agricultural and forest residues. The underlying biogeochemical mechanisms were examined using long-term soil incubations and empirical modeling.
Results showed the largest labile nitrogen pool in biochar made from cattle manure, resulting in the highest cumulative N2O emissions, while biochar derived from plant residue, including pecan shells, reduced N2O emissions by up to 24%.
Soil N2O emissions reduction was also more significant with increasing pyrolysis temperature. In summary, labile N content in biomass and pyrolysis temperature determined N2O emissions mitigation potential in biochar-amended soils. The study concludes that biochar prepared from plant derived feedstocks is effective in reducing N2O emissions from agricultural soils.
- USDA–NASS, 2022 ↩︎
- Singh, A., Ghimire, R., Aryal, D. R., Omer, M., Adhikari, A. D., Idowu, O. J., & Heerema, R. (2025). Soil carbon sequestration and biological health under pecan orchards of varying ages. Soil Science Society of America Journal, 89, e70089. https://doi.org/10.1002/saj2.70089 ↩︎
- Sapkota, S., Ghimire, R., Brewer, C.E. et al. Contrasting effects of plant and animal residue biochars on soil health, carbon stability, and crop yield. J Soils Sediments 25, 703–717 (2025). https://doi.org/10.1007/s11368-025-03968-1 ↩︎
- Sharma, B., Ghimire, R., Sapkota, S., Shrestha, P., Brewer, C. E., & Adhikari, S. (2025). Nitrous oxide mitigation potential of biochar derived from agricultural and forest biomass: Effects of feedstock composition and pyrolysis temperature. Journal of Environmental Quality, 1–13. https://doi.org/10.1002/jeq2.70054 ↩︎
Jan-Willem Jansens
Very interesting! Did researchers find a difference between (cost) effectiveness of biochar in meeting the goals of improvements of soil health, carbon emissions, and plant productivity in well develop orchard soils vs. poor range, woodland and forest soils (soils that need improvement from restoration work after years of erosion or wildfire)? Or would the latter soils first need to be treated with other means before biochar becomes an effective and cost effective strategy for such depleted soils?
Thank you
admin
The focus of the center is on agricultural soils rather than natural ecosystems, Jan-Willem, although forests and rangeland are of course also “working lands” and it would make for an interesting comparison. When applying biochar to depleted soils in general, it is best to inoculate or “charge” the biochar with beneficial organisms and water –see our post Exploring Biochar: Post-Production Activation