03/02/2020

The following examples of agricultural-related publications and were published during the year in 2019.  The publications may extend before and beyond the project period of October 2018 - September 2019. These publications represent a small subset of the total research activities that utilizes NADP data and infrastructure.  The full associated publication bibliography is avaible on the NADP web site.

Chang, Y. et al. Assessing contributions of agricultural and nonagricultural emissions to atmospheric ammonia in a Chinese megacity. Environmental science & technology, v. 53, n. 4, p. 1822-1833, 2019. ISSN 0013-936X.

Hember, R. A. Spatially and temporally continuous estimates of annual total nitrogen deposition over North America, 1860–2013. Data in brief, v. 17, p. 134-140, 2018. ISSN 2352-3409.

Jeong, H.; Pittelkow, C. M.; Bhattarai, R. Simulated responses of tile-drained agricultural systems to recent changes in ambient atmospheric gradients. Agricultural systems, v. 168, p. 48-55, 2019. ISSN 0308-521X.

Khan, M. S.; Koizumi, N.; Olds, J. L. Biofixation of atmospheric nitrogen in the context of world staple crop production: Policy perspectives. Science of the Total Environment, p. 134945, 2019a. ISSN 0048-9697.

Koskelo, A. I. et al. Biogeochemical storm response in agricultural watersheds of the Choptank River Basin, Delmarva Peninsula, USA. Biogeochemistry, v. 139, n. 3, p. 215-239, 2018. ISSN 0168-2563.

Ludwikowski, J. J.; Peterson, E. W. Transport and fate of chloride from road salt within a mixed urban and agricultural watershed in Illinois (USA): assessing the influence of chloride application rates. Hydrogeology Journal, v. 26, n. 4, p. 1123-1135, 2018. ISSN 1431-2174.

Sosa Echeverria, R. et al. Sulfur and nitrogen compounds in wet atmospheric deposition on the coast of the Gulf of Mexico from 2003 to 2015. Science of the Total Environment, v. 700, p. 134419, 2020/01/15/ 2020. ISSN 0048-9697.

Select Science Fall Symposium Presentations

During the fall meeting in Boulder, 37 talks and 41 posters were presented.  These represent the full diversity of NADPs research and outreach efforts and included international presenters from Canada, Mexico, South Korea, China, and India.  A select set of presentations are highlighted below, submitted abstracts highlighted below may have been edited for content and brevity:

The patterns of emissions and depositions of selected air pollutants in China during 2005-2018

Xi Mengxiao, Yu Zhao, Xuejun Liu, Qiang Zhang, Yuepeng Pan, Yang Liu and Lei Zhang: The paper presented the pattern of long-term SO₄ ^2-, NH₄ ⁺ and NO₃ ^- bulk deposition along with the SO₂,NH₃ and NO_X emission in China from 2005 to 2018. The Generalized Additive Models (GAMs) were constructed to predict the decadal bulk deposition of sulfate, ammonia and nitrogen, through the integration of satellite columns, PM_2.5 concentration, land-use information and meteorology variables.

Trends in Wet Deposition of Organic Nitrogen in the Rocky Mountains. Katherine Benedict, Bret A. Schichtel and Jeffrey L. Collett Jr. In this study the seasonal and annual variations of organic nitrogen at Rocky Mountain National Park from measurements made between March to October from 2008 to 2019 was investigated. This record of data using the sample measurement and collection techniques provides a unique look at wet organic nitrogen deposition in a sensitive ecosystem.

Patterns of atmospheric and soil mercury in the conterminous U.S. Charles Driscoll, Connor Olson, Benjamin Geyman, Elsie Sunderland, David Krabbenhoft and Michael Tate. This study summarized (i) temporal trends and spatial patterns of mercury emissions, (ii) atmospheric concentrations of mercury species and wet mercury deposition, and (iii) spatial patterns of soil mercury in the conterminous U.S. Observations of atmospheric chemistry were obtained from the Atmospheric Mercury Network (AMNet) and wet deposition data were obtained from the Mercury Deposition Network (MDN) of the NADP. Concentrations of surface soil mercury were generally highest in the East, coinciding with higher concentrations of soil organic matter and an abundance of forest cover, and generally lower in the West except for elevated concentrations in lands adjacent to the Pacific coast. Forested lands generally exhibited the highest mercury concentrations in surface soils, followed by developed lands, planted/cultivated lands, herbaceous uplands, shrublands, and barren lands.

Chronic and Episodic Acidification of Streams along the Appalachian Trail Corridor, eastern United State. Douglas A Burns, Todd C. McDonnell, Karen C. Rice, Gregory B. Lawrence and Timothy J. Sullivan. The study evaluated stream acidification in 269 headwaters along the Appalachian Trail (AT) across the eastern U.S. The AT is an ideal study region because it transits several eco-regions, is located downwind of high levels of S and N emission sources and includes heterogeneous soils and geology. Chronic acidification at low flow was substantial as 16% of streams had a mean acid-neutralizing capacity (ANC)

A 40 Site Network for Passive Ammonia Measurements along northern Utah's Wasatch Front: Winter and Summer 2019. Randy Martin , Kerry Kelly, Jaron Hansen, Nancy Daher and Christopher Pennell. The Wasatch Front is considered a series non-attainment area for PM_2.5. Several studies, most recently the 2017 Utah Winter Fine Particulate Study (UWFPS), have pointed out that although the local airsheds appear to be slightly ammonia-rich in regards to NH₄NO₃ formation. There are times, especially during extended persistent cold-pool, capping events (inversions) in which the atmosphere switches to a more ammonia-limited regime. A study was initiated for the winter and summer of 2019 in which a dense network (40 sites) of Ogawa passive NH₃ samplers were deployed from Brigham City to Mona, UT, approximately 140 miles, which include the population centers of Ogden, Salt Lake City and Provo. The winter study took place from mid-January to mid-February and the summer study extended from mid-July to mid-August. Preliminary analysis showed the average winter NH₃ concentrations (≈5-10 ppb) were lower than the average summer values (20-30 ppb), with notable difference between the Salt Lake and Utah county airshed.

Evaluation of the Efficacy of the National Atmospheric Deposition Program (NADP) National Trends Network (NTN) for Assessment of PFAS Deposition in Precipitation. Martin Shafer, Mark Olson, Camille Danielson and Kirsten Widmayer. This pilot study investigated the efficacy of the NADP precipitation samples for PFAS deposition determination and provides new data on levels of PFAS in precipitation across the US. PFAS measurements were performed on geographically diverse precipitation samples from the NADP National Trends Network (NTN) and in parallel conducted laboratory and field experiments designed to examine whether the NTN as currently configured would support using the large network of 255 sites as a national PFAS sampling network. Concentrations of the detectable PFAS species were low, generally less than 1 ng/L, though the sum of the quantified species exceeded 4 ng/L at many sites. The carboxylic acid species were by far the most frequently detected, with PFHxA, PFHpA, PFOA and PFNA each present in nearly 70% of all samples. Shorter-chain PFAS compounds dominated, with no PFAS compounds with carbon numbers greater than nine detected. Sites from the Mid-Atlantic States generally had the greatest number of detectable PFAS species and highest concentrations.

Posters:

Experimentally derived nitrogen critical loads for northern Great Plains vegetation. Amy Symstad, Anine T. Smith, Wesley E. Newton and Alan K. Knapp.  The critical load concept facilitates communication between scientists and policy makers and land managers by translating the complex effects of air pollution on ecosystems into unambiguous numbers that can be used to inform air quality targets. Anthropogenic atmospheric nitrogen (N) deposition adversely affects a variety of ecosystems, but the information used to derive critical loads for North American ecosystems is sparse and often based on experiments investigating N loads substantially higher than current or expected atmospheric deposition. In a four-year field experiment in the northern Great Plains (NGP), where current N deposition levels range from ~3 to 9 kg N/ ha/y, we added 12 levels of N, from 2.5 to 100 kg N/ha/y, to three sites spanning a range of soil fertility and productivity. Our results suggest a conservative critical load of 4 to 6 kg N/ ha/y for the most sensitive vegetation type we investigated – Badlands sparse vegetation, a community that supports plant species adapted to low fertility conditions – for which N addition at this rate increased productivity and litter load. In contrast, for the two more productive vegetation types characteristic of most NGP grasslands, a critical load of 6 to 10 kg N/ha/y was identified. For these vegetation types, N addition at this level altered plant tissue chemistry and increased non-native species. These critical loads are below the currently suggested range of 10 to 25 kg N/ha/y for NGP vegetation and within the range of current or near-future deposition, suggesting that N deposition may already be inducing fundamental changes in NGP ecosystems.

Cloud and Fog Deposition: Monitoring in High Elevation and Coastal Ecosystems. The Past, Present and Future. Selma Isil, Jeffrey L. Collett, Jr., Peter Weiss-Penzias3, Christopher Rogers and Jason Lynch. Deposition of pollutants by cloud water exceeds deposition by precipitation and dry deposition in high elevation settings. The large loading of pollutants in such environments is due to a combination of factors such as high frequency of cloud immersion, high wind speeds, orographic enhancement of precipitation, and large leaf area of tree species typical in these environments. Fog impacted coastal ecosystems also experience higher pollutant loadings similar to cloud impacted high elevation sites. Therefore, development of meaningful critical load values and total nitrogen budgets for high elevation and fog impacted sites requires reliable cloud and fog water deposition estimates. However, the cost and labor intensity of cloud water sample collection have made it difficult to conduct long-term studies that would provide the data needed to develop accurate estimates. Current understanding of fog formation, transport, and the role of fog in hydrogeological and biogeochemical cycles is incomplete due, in part, to lack of a concerted interdisciplinary approach to the problem. Historically, these obstacles have limited collection of cloud and fog water samples. Summary results from a small cloud water monitoring network that operated in the Appalachian range from the mid-nineties through 2011, as well as a qualitative review of other cloud and fog water studies conducted in the United States, Europe, South America/Pacific, and Asia will be presented. Current research findings and collection methods will also be reviewed. Recent scientific efforts by the NADP’s Total Deposition Science Committee and NADP’s Critical Loads of Atmospheric Deposition Science Committee have identified occult deposition as a “need” in developing critical loads for ecosystems that experience significant cloud and fog impaction.

Determining adequate levels of nitrogen and sulfur deposition to prevent harmful tree species level decreases. Justin Coughlin, Christopher M. Clark, Robert Sabo, Jeremy Ash, Jennifer James, Travis J. Smith and Linda Pardo.  Ecosystems in the United States have experienced extensive nitrogen and sulfur deposition decreases over the last thirty years resulting in lower levels of acidic rain, lessening eutrophication, and declining soil acidification. As nitrogen and sulfur deposition continue to decrease, policy frameworks can be established to determine adequate levels of deposition to protect species diversity and abundance. Recent advances in quantifiable deposition effects on individual tree species in the contiguous United States (CONUS) have presented novel data on the growth and survival rates of 94 different tree species including new critical load information. Using the most current NADP total nitrogen and sulfur deposition (dry + wet) surfaces, the United States Forest Service’s live tree basal area surfaces, and the newly available tree species response curves, we have generated forest-level rasters showing the net (negative and positive) effects on tree species across the CONUS from 2014-2016 averaged total nitrogen and sulfur deposition. In addition, deposition magnitude CONUS rasters have been modeled to determine levels that would ensure forest growth and survival rates do not exceed 5 and 1%, respectively. This pertinent information can be used in policy decisions to ascertain appropriate ambient level concentrations of NOx and SOx ensuring forests are not adversely harmed.

An investigation into the importance of amine compounds to organic nitrogen in aerosol. Evelyn Bangs, Katherine B. Benedict, Amy P. Sullivan and Jeffrey L. Collett Jr. In Northeastern Colorado agriculture is an importance source of atmospheric nitrogen compounds, specifically and most commonly studied is ammonia. However, amines are also emitted from a variety of agricultural activities but few studies have focused on these organic nitrogen compounds and the processes that these compounds will undergo to form particulate matter. A set of samples from the spring of 2019 (April) were collected using URG denuder/filter-pack sampling in the following Colorado locations: Greeley, Fort Collins, and in Rocky Mountain National Park (RMNP). These samples were analyzed for a suite of amine compounds, inorganic ions, and total nitrogen (TN). Additionally a Micro-Orfice Uniform Impactor Depositor (MOUDI) was operated at the Fort Collins site to collect highly resolved size distribution data was collected for the summer and winter seasons. The MOUDI samples were analyzed for inorganic ions, amines, and organic acids to assess the processes that were forming amine particulate. While 16 different amines were analyzed, there were several that were observed below the detection limit. The amines that were observed in higher concentrations included methylamine, dimethylamine, trimethylamine, tert-butylamine, sec-butylamine, isobutylamine, and amylamine. In this study we will examine the contribution of amines to total organic nitrogen and the inorganic nitrogen species measured. We will also investigate the size distribution of the various measured species to better understand aerosol formation processes in the region. Amines were generally greatest in concentration at the Greeley site and smallest in concentration at the RMNP site, as we expected due to proximity of sources.

Agricultural Ammonia Monitoring. Sung-Chang Hong, Sae-Nun Song, Kyeong-Sik Kim, Sun-Young Yu and Gyu-Hyeon Lee. Ammonia (NH3) generated from the agricultural sector is known as a precursor to fine particulate matter. Fine particulate matter (PM2.5) which is secondarily generated is more dangerous to human bodies than particulate matter (PM10) and it is generated in the air by chemical reaction with various substances such as nitrogen oxides (NOx) and sulfur oxides (SOx). There are various research results which say that the most effective method to reduce fine particulate matter is to control ammonia. Therefore, it is necessary to monitor the amount of ammonia generated in the agricultural sector. Accordingly, we are planning to establish a long-term monitoring system for ammonia and air pollutants in agricultural areas. The ammonia and air pollutant observatory site is planning to select and install monitoring systems focusing on large-scale agricultural areas in the paddy area, upland crop area, cultivation under structure area, and fruit tree growing area. The samples are to be collected from atmospheric dry samples, wet samples, PM10, and PM2.5. The major analytical items are ammonium ion (dry and wet) and gaseous ammonia (passive atmospheric sampling). From this year on, we are conducting research projects which are developing of the emission inventory of ammonia for paddy rice, upland crops and plastic house cultivation crops. Crop land sector needs to enhance, to newly develop emission factors by crop, cultivation method, nutrient input material (urea fertilizer, cow manure compost, pig manure compost and poultry manure compost), application time, and cultivation environments in Korea. The status and characteristics of ammonia emission by major crop cultivation areas in the agricultural sector will be analyzed and the characteristics of ammonia and air pollutant emissions in the agricultural area with the national atmospheric ammonia concentration, urban air pollution observation network, and emission characteristics of atmospheric pollutants will be compared.

An Integrated N Cycling Approach with Agriculture, Atmosphere, and Hydrology Models. Limei Ran1, Yongping Yuan, Jonathan Pleim, Rohit Mathur, Ruoyu Wang, Dongmei Yang, Wenlong Liu7, Verel Benson, Ellen Cooter and Jimmy Williams. The poster presented an integrated modeling system (IMS) with agriculture (EPIC - Environmental Policy Integrated Climate), atmosphere (WRF/CMAQ - Weather Research and Forecast model and Community Multiscale Air Quality), and hydrology (SWAT - Soil and Water Assessment Tool) models to assess the interactions among land-air-water processes. The centerpiece of the IMS is the Fertilizer Emission Scenario Tool for CMAQ (FEST-C) which includes a Java-based interface and EPIC adapted to regional applications along with built-in database and tools. The Linux-based interface guides users through EPIC simulations for any CMAQ grid domain over the conterminous United States (CONUS) and integration among the multimedia models. This presentation focuses on the description of the currently released FEST-C and the impact assessment of agricultural fertilization on air quality through an improved CMAQ bi-directional ammonia approach. As N deposition is also an important source altering N cycling, the influence of nitrogen deposition along with weather variability on cultivated soil N budget will also be examined for CONUS. The system is applied over CONUS with a 12km resolution for 2010, 2011, and 2012. EPIC simulations are conducted using WRF/CMAQ weather and N deposition for these years and cases adjusted to represent conditions in the early 1990s for assessing the impacts of N deposition reduction since 1990 due to tightened NOX emission standards under the Clean Air Act (CAA). SWAT integrated with EPIC and WRF/CMAQ are then applied to the Mississippi River Basin (MRB) to simulate watershed hydrology and water quality for these years under different N deposition conditions. Preliminary results demonstrate that air quality linked with simulated agriculture improves NH3 flux estimation and results in better performance for N cycling in the atmosphere. The N budget in agricultural production is sensitive to weather variability and atmospheric N deposition with increased N fertilization and decreased N loss in areas with N deposition reduction.

 

 

05/30/2020

12/30/2020

Publications

The NADP tracks the number of journal and report publications for each calendar year that use NADP data in their research. During CY2019, we found 248 publications (almost all refereed articles) that used NADP data in some important way to further their research (one of our objectives). This publication tracking continues in 2020 and will be reported after 2020 is complete. The complete list of journal articles used can be found here: http://nadp.slh.wisc.edu/lib/bibliography.aspx.

The following are a subset of journal articles using NADP data that should be of particular interest to agricultural researchers.

1. Ran, L., Yuan, Y., Cooter, E., Benson, V., Yang, D., Pleim, J., ... & Williams, J. (2019). An integrated agriculture, atmosphere, and hydrology modeling system for ecosystem assessments. Journal of Advances in Modeling Earth Systems, 11(12), 4645-4668.

The authors (EPA and university researchers) are developing a regional scale integrated model to account for compounds moving back and forth between agricultural systems, the atmosphere, and the hydrosphere. This current release adds a soil and water assessment tool to the model, and more fully integrating agricultural sources and systems into the predictions. A particularly important part of this model is nitrogen cycling. The authors are currently testing the model for accuracy against known values, and are particularly focused on a new “bidirectional ammonia” component. They are able to simulate relatively accurate ammonium concentrations in the Mississippi River Delta.

 

The model uses data from two NADP networks (AMON and NTN) over multiple years and incorporates our gaseous ammonia measurements and wet deposition ammonium measurements into the model predictions.

2. Botero-Acosta, A., Chu, M. L., & Huang, C. (2019). Impacts of environmental stressors on nonpoint source pollution in intensively managed hydrologic systems. Journal of Hydrology, 579, 124056.

The objective of this study was to simulate the impacts of Water Management Practices on the sediment and nitrate-nitrogen (NO3-N) stream loads in an intensively managed agro-ecosystem watershed. The authors develop a basic model in Illinois to track the cycling of NO3-N in these systems. The authors predict that WMPs, such as crop rotation and cover crops, presented the highest reductions of simulated NO3-N and sediment load, respectively. They also predict that climate conditions had a strong impact on the transport of pollutants.

The authors used, as model input, the NADP wet depositional and precipitation measurements from our IL11 site near Champaign for multiple years.

3. Groshans, G. R., Mikhailova, E. A., Post, C. J., Schlautman, M. A., Cope, M. P., & Zhang, L. (2019). Ecosystem services assessment and valuation of atmospheric magnesium deposition. Geosciences, 9(8), 331.

These authors studied the ecosystem services from atmospheric magnesium (Mg2+) deposition which is a source of naturally-occurring fertilizer and liming material that is rarely considered in modeling. They conclude that the atmospheric magnesium deposition flow was valued at $46.7 million U.S. dollars ($18.5M wet + $28.2M dry) based on an average 2014 price of agricultural dolomite (CaMg(CO3)2). Additionally, this resource “plays an important role in the pedosphere”.

The authors used the wet deposition and estimated dry deposition of magnesium from all continental NADP sites for years 2000–2015. This data use also included the dry deposition measurements from our Total Deposition effort.

4. Ilampooranan, I. (2019). Modeling nutrient legacies and time lags in agricultural landscapes: a Midwestern case study. Doctoral Dissertation, Civil and Environmental Engineering (Water), University of Waterloo.

Ilampooran (Dissertation) studied the legacy nutrient storage of nitrogen in the subsurface, built up over decades of fertilizer application which contribute to time lags between the implementation of best management practices and water quality improvement. Legacy effects are not well quantified. The author’s goal was a model to quantify legacy stores and time lags in intensively managed agricultural landscapes in the Midwestern US. The author estimated that the subsurface legacy nitrogen storage as 33.3 kg/ha/yr, and determined it to be a significant component of the overall mass budget; approximately 31% of the fertilizer added to the watershed every year. The findings highlight that using additional data sources to improve hydrological consistency of distributed models increases their robustness and predictive ability.

The authors used wet deposition measurements from four NADP sites in and around Iowa, and used NADP ammonium and nitrate measurements for the years 1985 to 2012. The authors used NADP information to estimate county level N deposition to the study areas (basically Iowa).

5. Jeong, H., Pittelkow, C. M., & Bhattarai, R. (2019). Simulated responses of tile-drained agricultural systems to recent changes in ambient atmospheric gradients. Agricultural Systems, 168, 48-55.

University of Illinois scientists studied the field-scale hydrology, nitrogen (N) dynamics, and crop yields in two tile-drained fields under a corn-soybean rotation in Illinois. They modelled root-zone water quality under changing nitrogen concentration and deposition conditions. Changing nitrate concentration in rain water “demonstrated a moderate impact on N dynamics (e.g. nitrate losses to tile drainage increased up to 5.8% compared to the baseline scenario)” and had a small impact on field scale hydrology and crop yield. Also, this decrease may partially be related to the slight improvements in water quality in Illinois during the last decades.

NADP nitrogen deposition information was used from the IL11 wet deposition site for multiple years, and the NADP nitrate concentration maps for the continental US (1990-2015).

6. Piña, A. J., Schumacher, R. S., Denning, A. S., Faulkner, W. B., Baron, J. S., Ham, J., ... & Collett, J. L. (2019). Reducing Wet Ammonium Deposition in Rocky Mountain National Park: the Development and Evaluation of A Pilot Early Warning System for Agricultural Operations in Eastern Colorado. Environmental Management, 64(5), 626-639.

The authors investigated the impact of agricultural emissions of ammonia (NH3) deposition in Rocky Mountain National Park (RMNP), and an early warning system of agricultural ammonia moving into the park. The system uses trajectory analysis, meteorological data, and NADP wet deposition data recorded in the park. They concluded that the system accurately predicted 6 of 9 high N deposition weeks at a lower-elevation observation site, but only 4 of 11 high N deposition weeks at a higher-elevation site. They also determined that 75% of local agricultural producers voluntarily responded to alerts and altered their practices.

The authors used weekly observations of N deposition at two locations in/near the Park for multiple years (1985-present), and use the observations as part of their model warning input data.

7. Birdsey, R. A., Dugan, A. J., Healey, S. P., Dante-Wood, K., Zhang, F., Mo, G., ... & McCarter, J. (2019). Assessment of the influence of disturbance, management activities, and environmental factors on carbon stocks of US national forests. Gen. Tech. Rep. RMRS-GTR-402. Fort Collins, CO: US Department of Agriculture, Forest Service, Rocky Mountain Research Station. 116 pages plus appendices, 402pp.

The authors (including USDA scientists) have developed a modeling system to estimate standing carbon stocks in US National Forests, and for individual forests and regional areas. The InTEC model is a process-based biogeochemical model driven by monthly climate data, vegetation parameters, and forest disturbance information to estimate the relative effect of disturbance (e.g., fires, harvests, insect outbreaks, disease) and nondisturbance factors (climate, carbon dioxide concentration, nitrogen deposition) on forest-level C accumulation and fluxes. They conclude that carbon stocks are generally increasing in forests of the eastern US, and individual western forests are either increasing or decreasing depending on recent effects of natural disturbances and climate change.

Nationwide NADP data was used as an input to the model, including multiple years of data and all NTN sites.

8. Lu, C., Zhang, J., Cao, P., & Hatfield, J. L. (2019). Are we getting better in using nitrogen?: Variations in nitrogen use efficiency of two cereal crops across the United States. Earth's Future 7(8), 939-952.

The authors (including an ARS scientist) studied the nitrogen use efficiency in separate crops at the state level for corn and winter wheat. These two crops account for 50% of fertilizer use in the US. Efficiency use in corn begins to decline when N fertilizer application rate exceeds ~150 kg N ha−1 yr−1, and that yield response of winter wheat slows down with annual N fertilizer input above ~50 kg N ha−1 yr−1. However, nitrogen use efficiency in both crops has risen in recent decades, which could potentially reduce N loss from agricultural production. Furthermore, this study indicates that annual dynamics of N surplus in corn is closely tied with grain yields, while that in winter wheat significantly correlates with N fertilizer input.

The authors used all NTN site data for nitrogen deposition information (2000 and on), and used the measurement data to extrapolate back in time for deposition for periods before dense measurements were available.

9. Mikhailova, E. A., Post, G. C., Cope, M. P., Post, C. J., Schlautman, M. A., & Zhang, L. (2019). Quantifying and mapping atmospheric potassium deposition for soil ecosystem services assessment in the United States. Frontiers in Environmental Science 7, 74.

The authors estimated the contribution of atmospheric deposition of potassium as a “provisioning value” to soil ecosystem services, based upon its value as an essential element and component of many fertilizers. Atmospheric deposition flows (wet, dry, and total) had a total provisioning ecosystem value of atmospheric potassium deposition was over $406 million U.S. dollars ($179M wet +$227M dry) per year based on a 5-year moving average of $500 per metric ton of potassium chloride (KCl) fertilizer in the U.S (over 10 years). The highest ranked regions for total value of K+ deposition per year were: (1) West ($86.5M), (2) South Central ($80.4M), and (3) Southeast ($80.2M), with the highest value in (1) Texas ($44.3M), (2) California ($18.3M), and (3) New Mexico ($1.35M). The results of this study provide a methodology to estimate potassium deposition value for ecosystem services assessments, and for conducting nutrient audits at various scales to address the United Nations (UN) Sustainable Development Goals.

The authors used NADP’s annual deposition of potassium maps (all sites) from 2000 through 2015.

 

10. Zikalala, P., Kisekka, I., & Grismer, M. (2019). Calibration and global sensitivity analysis for a salinity model used in evaluating fields irrigated with treated wastewater in the Salinas Valley. Agriculture 9(2), 31.

The authors investigated an irrigation salinity water quality model for use for soil salinization information. The goal was to estimate the impact on blending treated wastewater into irrigation water and its impact on soil salinity and on different crops (vegetables, strawberries, artichoke). The model did predict long-term salinity trends, but underestimated electrical conductivity. Using a 50 year simulation, salt loading was estimated to be quite high, but root zone salinity did not exceed current thresholds.

NADP’s weekly electrical conductivity of precipitation data was used from the closest site to the agricultural fields (Pinnacles National Park), from 2000 to current.

07/09/2021