Date of this Version
Environmental Studies Undergraduate Student Thesis, University of Nebraska-Lincoln, 2021.
This meta-analysis investigates the possible carbon sequestration of no-till and cover crop practices on Nebraska farmlands. These management practices are part of regenerative agriculture, a farming method designed to mitigate and adapt to climate change. As climate change is expected to significantly reduce yields in Nebraska, sequestering carbon in farmlands offers a way to adapt to climate change impacts and lower the concentration of carbon dioxide in the atmosphere. However, changing management practices is difficult and is driven primarily by economics. This study aims to determine how much carbon these practices can sequester in Nebraska soil each year by evaluating the soil organic carbon (SOC) change from studies across the Midwest United States, with the goal that sequestration rates from this study can be used by Nebraska farmers to understand the returns of these management practices when coupled with carbon sequestration programs. To accomplish this, we reviewed studies investigating no-till practices (ten sites) and cover crop practices (ten sites) from the Midwest. Parameters including study length, site precipitation, and average temperature at each site were included and the relationship of those parameters to carbon sequestration rates were investigated. These parameters were not strongly correlated to carbon sequestration rates of no-till sites, though precipitation was strongly correlated to carbon sequestration under cover crops. A mean carbon sequestration rate for no-till (0.417 ± 0.54 Mg ha-1 yr-1) and cover crops (0.136 ± 0.11 Mg ha-1 yr-1) were calculated. Using the mean carbon sequestration rates for each management practice, Nebraska soils could store a total of 4,980,339 Mg C each year by using both no-till and cover crops on all farmlands, offsetting half of Nebraska’s agricultural emissions.