We discovered high concentrations of PFAS (18.53 +/- 1.5 mu g kg-1) in yard waste compost, a compost type widely acceptable to the public. Seventeen out of forty targeted PFAS, belonging to six PFAS classes were detected in yard waste compost, with PFCAs (13.51 +/- 0.99 mu g kg-1) and PFSAs (4.13 +/- 0.19 mu g kg-1) being the dominant classes, comprising approximately 72.5% and 22.1% of the total measured PFAS. Both short-chain PFAS, such as PFBA, PFHxA, and PFBS, and long-chain PFAS, such as PFOA and PFOS, were prevalent in all the tested yard waste compost samples. We also discovered the co-occurrence of PFAS with low-density polyethylene (LDPE) and polyethylene terephthalate (PET) plastics. Total PFAS concentrations in LDPE and PET separated from incoming yard waste were 7.41 +/- 0.41 mu g kg-1 and 1.35 +/- 0.1 mu g kg-1, which increased to 8.66 +/- 0.81 mu g kg-1 in LDPE and 5.44 +/- 0.56 mu g kg-1 in PET separated from compost. An idle mature compost pile revealed a clear vertical distribution of PFAS, with the total PFAS concentrations at the surface level approximately 58.9-63.2% lower than the 2 ft level. This difference might be attributed to the volatile loss of short-chain PFCAs, PFAS's downward movement with moisture, and aerobic transformations of precursor PFAS at the surface. This novel investigation revealed substantial PFAS contamination and plastic-PFAS co-occurrence in yard waste compost. Insights gained from the distribution of PFAS in compost are valuable for improving its management and application.

Cover crops are an effective way to reduce soil erosion and promote soil health. However, in North Dakota and other northern climates where corn (Zea mays L.) is an important commodity crop, killing frosts generally occur before harvest, leaving little opportunity for cover crop planting. By interseeding cover crops into corn during the growing season, the cover crops are given a longer period to establish. The purpose of this study was to identify the impact cover crops interseeded into wide-row (60-inch) corn have on soil water content and corn productivity. Two experimental sites were established in 2020 near Leonard and Rutland, ND. Both sites were organized into randomized complete block designs, with three cover crop treatments in Leonard (n = 9) and four cover crop treatments in Rutland (n = 16). Cover crops were no-till drilled into the corn at the V4 growth stage. The cover crop treatments were diverse mixes developed to either provide pollinator habitat, overwinter, or winter-kill. Throughout the growing season, soil gravimetric water content and cover crop biomass was monitored. At the end of the growing season, dry cover crop biomass ranged from 189 to 1445 lb ac-1. The presence and type of interseeded cover crops did not have a statistically significant effect on soil water content or corn yield. It is suspected the above average precipitation during the month of July led to adequate amounts of soil water for the entirety of the cover crop growing season, limiting the difference between treatments. Northern climate corn farmers face challenges with soil erosion and need to improve soil health. Planting cover crops can help, but short growing seasons in places like North Dakota makes it difficult. One way to establish cover crops in areas with short growing seasons is interseeding-planting the cover crop between rows of corn as it grows. Corn is typically planted with a 30-inch row spacing, which provides full canopy cover and shading of the soil surface, which limits the growth of interseeded cover crops. Increasing the row-width to 60 inches allows more sunlight to reach the cover crop. This study was carried out at two sites in North Dakota and showed interseeding cover crops into 60-inch corn did not significantly affect soil moisture or corn yield. This insight can guide farmers in making informed decisions about sustainable farming practices.

Abstract High concentrations of sodium chloride dominate oilfield produced waters (brine) of the Williston Basin. When accidental spills of produced waters occur, there is an immediate need to reduce concentrations of chloride, to protect surface and groundwater systems and to reduce concentrations of sodium (Na) in soil to prevent any unwanted swelling and dispersion in soil. Swelling and dispersion of soils will likely occur if sodium adsorption ratio values are too high and the electrical conductivity drops below a certain threshold that is required to maintain flocculation. To prevent this, a calcium (Ca) amendment can be applied to replace Na with Ca on soil exchange sites. Historically, gypsum has been the most common Ca amendment used for improving brine impacted soils. Flue gas desulfurization gypsum is available in North Dakota but is still a sparingly soluble amendment. The purpose of this research was to investigate the use of calcium acetate (Ca‐Ac) as an amendment for brine‐impacted soils as compared to gypsum. Ca‐Ac has a similar concentration of Ca compared to gypsum but is over 100 times more soluble than gypsum. This laboratory experiment will compare how varying levels of gypsum and Ca‐Ac can influence soil hydraulic conductivity, and chemical and physical properties when mixed with oilfield brine‐impacted soils.

Abstract Due to its benefits, including but not limited to increased access to affordable healthy food, bringing communities together for a common goal, and improving food security, urban agriculture is gaining popularity across the United States. Although soil‐based information is available at the national level, people in urban environments may have limited details about the soils in their communities. To bridge the gap between rural and urban agriculture, city, state, and federal agencies such as the Natural Resources Conservation Service could expand upon the soil survey programs that currently exist and are available within the WebSoilSurvey. Additionally, trace element testing and interpretation would allow for improved knowledge about the risks that urban soils may have on food quality for those interested in urban agriculture. Core Ideas Detailed soil science information for urban agriculture may be lacking on a fine scale. Opportunities exist to support the soil science needs of urban growers via local, state, and federal entities. Information on urban soils can help provide healthy and sustainable foodstuffs.

Abstract Farmland within the Williston Basin of North Dakota was the site of the largest terrestrial oil spill to date in the United States in 2013. Over 3200 m3 of oil was released into the topsoil and subsoil, creating a risk to soil, water, and air resources. The purpose of this document is to provide a summary of results from a 7‐year project investigating the impacts of how thermal desorption (TD), the method used to remediate topsoil and subsoil, impacted contaminant reduction, soil function, and plant productivity simultaneously with site remediation. Soil disturbance and TD decreased soil organic matter and microbial communities, resulting in decreased soil function and plant production. However, TD did not reduce soil microbial recovery 4 years after treatment. Blending TD‐treated soil with uncontaminated topsoil appeared to minimize these negative effects and promote recovery of soil function. These findings provided critical information to stakeholders in the understanding of soil remediation and reclamation in this region.

As the demand and cultivation of two-row malting barley (Hordeum vulgare L.) increases in the Northern Great Plains, updated nitrogen (N) recommendations are increasingly necessary. Not only does N play a role in grain yield, but it also impacts grain malting characteristics, including protein and kernel plump. To determine the impacts N rate and availability have on two-row malting barley, two experimental sites were established in eastern North Dakota during the 2020 and 2021 growing seasons. Treatments consisted of five fertilizer rates from 0 to 180 kg N ha-1 and two malting barley cultivars. Soil samples to be analyzed for nitrate-N were taken prior to planting and N credit estimates from the previous crop were considered to determine the total known available nitrogen (TKAN) in the soil. It was determined there was a strong relationship between N rate and grain yield along with a strong positive correlation between N rate and grain protein. No significant interactions between N rate and kernel plump were noted. When the relationship between relative grain yield and TKAN was modeled using a best-fit regression, maximum yield was attained at 210 kg TKAN ha-1 with a grain protein of 128 g kg-1, meeting malting quality requirements. When factoring in grain value and cost of urea fertilizer, the TKAN range needed to produce the crop at the highest profitability was lower than TKAN of maximum yield, ranging from 89 to 190 kg TKAN ha-1. Plant-available nitrogen (N) is a driver of both yield and grain protein content of two-row malting barley. Economic optimum N rates for two-row malting barley promote farmer profitability and grain quality. Total N application rates can be reduced by focusing on net profitability rather than maximum yield.

AbstractSoil salinity is a global issue that impacts crop production and requires management to contain and ameliorate. Although field‐scale assessments are limited, a recent strategy used to manage salinity in the Northern Great Plains is the wide‐spread adoption of subsurface drainage. Therefore, a study was conducted between 2013 and 2021 on a 57‐ha field in southeastern North Dakota where changes in soil salinity, groundwater quality, and grain yields (soybean [Glycine max], wheat [Triticum aestivum], and corn [Zea mays L]) were compared between subsurface tile drained (TD) and undrained (UD) areas at the field scale. Topsoil (0–15 cm) electrical conductivity of saturated paste extract (ECe) decreased at a rate of 0.15 dS m−1 year−1 for TD but increased 0.03 dS m−1 year−1 for UD. The groundwater electrical conductivity of water (ECw) decreased 0.5 and 0.3 dS m−1 year−1 for TD and UD, respectively. Soil ECe, chloride (Cl−), sulfate‐sulfur (SO42−‐S), calcium (Ca2+), sodium (Na+), and magnesium (Mg2+) concentrations increased with soil depth for TD and UD. However, these ion concentrations decreased with time for TD and stayed relatively unchanged or increased for UD. Groundwater ECw and ion concentrations decreased over time for TD and to a lesser extent for UD. Groundwater levels increased slightly for TD but increased more for UD, where high water tables caused wet soil conditions resulting in yield reduction in several years. Soybean yields increase by 0.18 and 0.06 Mg ha−1 year−1 for TD and UD, respectively. Wheat grain yield increased over time for TD and UD at similar rates (0.17 and 0.18 Mg ha−1 year−1, respectively). Corn grain yield increased slightly from 2016 to 2019 for TD, but decreased by 6.2 Mg ha−1 from 2016 to 2019 for UD due to wet soil conditions. Overall, the outcomes of this field‐scale study provide validation of similar outcomes reported in small‐scale studies for subsurface drainage as a management tool for soil salinity in the Northern Great Plains.

The development of horizontal drilling and hydraulic fracking has led to an increase in oil and natural gas extraction. Development of infrastructure to extract and transport these resources is expected to increase over the next few decades, resulting in extensive land disturbance. Although reclamation aims to sufficiently return disturbed lands to their pre-disturbance use in an ecological sense, reclaimed rights-of-ways (ROW) commonly produce reduced crop yields. The objective of this study was to use meta-analysis to determine soil disturbance trends across studies found in the peer-reviewed literature. Papers that reported soil property data on disturbed ROWs and adjacent undisturbed sites were retrieved by searching the Web of Science database. Papers were separated by climate regions, resulting in analyses being conducted for studies in semiarid and humid climate regions. Results indicate that soil bulk density, soil organic matter, and pH are significantly increased on reclaimed ROWs. Soil metrics not incorporated in meta-analysis due to insufficient observations or the possible presence of publication biases like a desire to publish significant results and poor study design (cation exchange capacity, calcium, phosphorus, magnesium, total nitrogen, electrical conductivity, sodium, sodium adsorption ratio, and texture) are assessed and discussed. Best management practices gleaned from studies incorporated into meta-analysis are discussed to provide strategies to limit soil property disturbances.

The soybean [Glycine max (L.) Merrill] relationship with the bacteria Bradyrhizobium japonicum is responsible for providing around 60% of the nitrogen (N) required for the crop and the remaining N comes from the soil or supplemental fertilization. To investigate if higher yields are possible, supplemental N studies and co-inoculation of Rhizobium with Azospirillum are necessary. This N rate (0, 30, 56, 112, 336 kg N ha−1) and inoculation study was conducted across eight environments in eastern North Dakota, USA, in 2021 and 2022. Also, the effect of supplemental N and co-inoculation on nodulation was evaluated. When N was applied at 112 kg N ha−1, nodulation was significantly inhibited. Co-inoculation increased the number of large nodules and the volume of nodules; however, the yield was not different from inoculation with B. japonicum. Nitrogen at 112 and 336 kg ha−1 increased grain yield, protein yield, and seed weight; however, the higher N rate decreased plant population. There were significant positive relationships between yield and protein content and seed weight, and negative relationships between oil and protein content, and yield and oil content. Based on a polynomial relationship, the highest yield (3711 kg ha−1) would be achieved at 273 kg N ha−1. The application of N resulted in a yield increase but using current prices may not be an economical choice. Additional research is necessary to verify if co-inoculation with efficient strains can improve biological N fixation.

Soil degradation due to salts affects over 100 countries, especially in arid and semi-arid regions where salts migrate to the plant root zone via capillary action when evapotranspiration exceeds rainfall. Soil salinity reduces germination, growth, and root development, impacting crop yields, while excess sodium decreases water movement into the soil. Soil properties, namely, electrical conductivity (ECe), sodium adsorption ratio (SARe), and pH (pHe), affected by sparingly and soluble salts, are typically analyzed using soil saturated paste (SP). However, a simpler and cost-effective alternative is assessing soil salinity using soil:water solutions at ratio 1:5 (SW). This study developed empirical models between EC 1:5 -ECe, SAR 1:5 -SARe, and pH 1:5 -pHe to monitor soil salinity and sodicity in Lajas Valley, Puerto Rico, an agricultural reserve with 1,140 mm of mean annual rainfall and soils classified as saline and/or sodic. The ECe Sampling, Assessment, and Prediction software for Response Surface Sampling Design (ESAP-RSSD) optimized soil sampling with 48 points. Measurements of EC, pH, cations (Ca 2+ , Mg 2+ , Na + ), and SAR were conducted using SP and 1:5 SW extracts. Simple linear regression models estimated ECe ( R 2 > 0.93, p < 0.0001) and SARe ( R 2 > 0.98, p < 0.0001) from 1:5 extracts. The pHe models varied with depth, showing a strong correlation ( R 2 > 0.62, p < 0.0001) from 0 to 30 cm and weakening ( R 2 > 0.27, p < 0.0022) from 90 to 120 cm. The simple linear regression models generally perform well for EC and pH variables, with better performance observed at shallower depths. SW proves to be a practical, cost-effective, and efficient method for assessing salt-affected soils in Lajas Valley. By enabling regular soil salinity analysis, the developed estimation models combined with SW extraction could improve soil management practices and agricultural productivity.

Reclamation of oil and gas disturbed soils is challenging due to diminished function (i.e., soil physical, chemical, and biological properties) from the loss of soil organic carbon (SOC) and potential mixing of topsoil and subsoil. Biostimulants are agro-products applied to soil to improve SOC formation, microbial nutrient cycling, and crop yields, suggesting their potential use in reclaiming oil and gas disturbed soils. However, studies on the ability of biostimulants to enhance reclamation in disturbed soils are limited. Therefore, research was conducted to determine if biological properties were affected by biostimulant products in soil collected from an active pipeline installation project. The study was conducted in a greenhouse using pots consisting of the following soil treatments: TS100 (100% topsoil), TS50 (1:1 by-weight subsoil/topsoil), TS25 (3:1 subsoil/topsoil), TS12.5 (7:1 subsoil/topsoil), and TS0 (100% subsoil). Blended soil either received a liquid inoculant or biotic mulch biostimulant and were planted with hard red spring wheat (Triticum aestivum) later on. Soil biological properties were generally influenced by topsoil concentration where TS50 consistently produced similar results to TS100, however, nitrogen (N) and phosphorus (P) were also influenced by biostimulant treatment. Additionally, wheat biomass was significantly greater in the liquid treatment, whereas the biotic mulch stimulated greater microbial abundance and activity. Overall, increased topsoil improved biological recovery in the short term, and the addition of biostimulants in blended soils can also enhance recovery regardless of topsoil content. However, it is unclear whether the recovery is sustained into the long-term without additional biostimulant application.

Abstract Infrastructure installation (e.g., pipelines) disturbs soils, often resulting in increased soil compaction (bulk density [Bd] and penetration resistance [PR]). The relationship of PR to Bd, gravimetric water content (Θg), and a suite of other properties were determined on seven topsoils to provide a model and database for reclamation specialists to use when assessing disturbed soils. Penetration resistance had a strong linear association with Bd, but higher Θg reduced the range of PR as Bd increased. Step‐wise regression identified Bd, Θg, texture, clay speciation, and organic matter as significant factors to predict PR. The model predicts PR from <1 to 8 MPa and closely match measured values. Soil Bd and Θg contributed to 84% of the model's explained variation in predicting PR. This study provides a tool for reclamation specialists that aids in understanding the risks associated with disturbances and highlights the importance of keeping Θg low during installation of pipelines.

Millions of ha of sodic soils exist around the world and the movement of water through these soils is most directly dictated by the concentration of Na and overall electrical conductivity of the soil, and minerology of the clay. Helping farmers, land managers, crop advisors, and students better understand why water moves or does not move in these soils is necessary so that proper management strategies for these soils can occur. The purpose of this article is to provide educators and extension specialists with demonstrations that help describe water movement through sodic and non-sodic soils. The first demonstration links water movement through sodic soils and how altering the concentration of Na and soluble salts influences water movement. The second demonstration allows audiences to link the movement of water through soil horizons having varying concentrations of Na, soluble salts, and clay. These demonstrations may be useful educational tools on how and why amendments are used for improving water movement within sodic soils and also to show restrictions in water movement through naturally-occurring natric or clay-enriched horizons.

The effects of thermal desorption (TD) on soil physical and chemical properties after crude oil contamination are recently well studied. However, there are limited field-scale studies on long-term soil biological property recovery such as microbial communities and plant growth, which are vital for meeting global agrosystem demands and restoring ecosystem health. This study describes the status of soil biological properties after 4 yr of crop production on oil-contaminated cropland remediated via TD and a modified land farming technique. Plots were constructed in 2015 with native, uncontaminated topsoil (A); TD-treated subsoil (TDU); untreated land-farmed subsoil (SP); TDU + A (TDA), and SP + A (SPA) where soil ratios were 1:1 by volume, and composted manure (CM) was applied at 40 Mg ha(-1). After 3 yr of crop production (2019) grain sorghum [Sorghum bicolor (L.) Moench] was planted. Soil microbial community characteristics were assessed through phospholipid fatty acid analysis and by estimating mycorrhizal root colonization. Notably, inherent soil chemical and physical properties influenced the recovery of microbial communities in remediated soils. However, sorghum biomass production in TDU was 50 +/- 9% greater than SP while the microbial abundance in these treatments remained similar. Mycorrhizal colonization variation likely reflected rhizosphere nutrient scarcity and not the interactions of either remediation strategy. Based on these results after 4 yr of cropping, TDU does not diminish soil microbial recovery, and when possible, blending TDU materials with topsoil provides the greatest level of recovery relative to topsoil only.

AbstractOil and gas extraction from the Bakken and Three Forks shale‐oil reserves often produces large volumes of highly saline water, or brine. Brine releases often cause soils to exhibit poor structural and edaphic properties. Because of these negative effects, active remediation is often attempted through the use of in‐situ and ex‐situ techniques. Unfortunately, many conventional methods can be time intensive, costly, and only partially effective. This study sought to determine if salts could be efficiently removed from coarse‐ and fine‐textured soils through the surficial application of a wicking medium consisting of an engineered, paper‐based humidifier wick or ground wheat (Triticum aestivum L.) straw while soils were irrigated from the subsurface with either purified water or a gypsum solution. Over a 56‐d period, the humidifier wick with a gypsum solution reduced extractable Na by 82 and 23% in the loam and silty clay columns, respectively. The humidifier wick with purified water treatments reduced extractable Na by 77 and 8% in the loam and silty clay columns, respectively. Ground straw reduced extractable Na by <12% in all cases. The humidifier wick reduced the mean soil electrical conductivity (EC) by >9 dS m–1 with the largest reductions at deeper depths (i.e., >15 dS m–1 or >90% removal). Results show that evaporative wicks are comparable to other surficial remediation techniques in removing salt mass from soil.

The potential impact of controlled drainage (CD), which limits drainage outflow, and subirrigation (SI), which provides supplemental water through drain tile, on surface water quality are not well known in the Red River Valley (RRV). In this study, water samples were collected and analyzed for chemical concentrations from a tile-drained field that also has controlled drainage and subirrigation modes in the RRV of southeastern North Dakota from 2012–2018. A decreasing trend in overall nutrient load loss was observed because of reduced drainage outflow, though some chemical concentrations were found to be above the recommended surface water quality standards in this region. For example, sulfate was recommended to be below 750 mg/L but was reported at a mean value of 1971 mg/L during spring free drainage. The chemical composition of the subirrigation water was shown to have an impact on drainage water and the soil, specifically on salinity-related parameters, and the impact varied between years. This variation largely depended on the amount of subirrigation applied, soil moisture, and soil properties. Overall, the results of this study show the benefits of controlled drainage on nutrient loss reduction from agricultural fields.