Quantifying Carbon Sequestration From an Enhanced Rock Weathering Application at an agricultural field in Nebraska

This dataset supports a Master’s thesis at the University of Nebraska–Lincoln and includes results from inductively coupled plasma mass spectrometry (ICP-MS), inductively coupled plasma optical emission spectrometry (ICP-OES), particle size analysis, lysimeter water chemistry, electromagnetic induction (EMI) mapping, crop yield, and plant nutrient uptake. The study was conducted at the University of Nebraska's Eastern Nebraska Research Extension and Education Center (ENREEC) near Mead, Nebraska, as part of the Carbon Sequestration Project 3 (CSP3).

The field site follows a no-till, rainfed corn–soybean rotation, with soybeans grown in even years. Yield and biomass data were provided by ENREEC farm management. The experimental design includes three treatments: olivine (sourced from Åheim, Norway), agricultural lime (Aglime), and a control. Each amendment was applied at a uniform rate of 3 metric tons per hectare on October 18, 2023, following harvest. The field is laid out in a strip design, with aglime applied to rows labeled 1–24, olivine to rows 25–48, and control treatments in rows 49–72. Soil samples are numbered accordingly, while lysimeter locations are identified with "L" labels.

The field layout consists of a rectangular grid with sampling rows spaced 9.14 m (30 ft) apart lengthwise and 12.19 m (40 ft) apart widthwise. Each row includes 12 sampling points across two rows, with interspersed guest rows where no heavy machinery enters. Lysimeters were installed in the center of each treatment block, with five lysimeters per treatment (15 total) placed 36.58 m (120 ft) apart. Soil samples were collected within a 1-meter radius around each lysimeter.

Sampling occurred at three time points: prior to amendment (October 18, 2023), immediately after amendment (same day), and at one year post-application (October 25, 2024). Soil sampling involved composite samples from two random points within a 1 m² area. Each sample was divided into two depths: 0–10 cm (topsoil) and 10–30 cm (subsoil). Approximately 200 g of topsoil and 400 g of subsoil were collected per location. All samples were duplicated to ensure reproducibility.

In total, the study includes 72 distinct row soil samples and 15 lysimeter-adjacent samples, collected annually. With duplicates across two depths, this totals 174 soil samples per year. The EMI dataset was used to map soil texture, organic matter, pH, and cation exchange capacity. These data help assess how soil variability affects weathering processes and carbon sequestration potential across treatments.