https://www.nature.com/articles/s43247-022-00662-9 Skip to main content Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript. Advertisement Advertisement Communications Earth & Environment * View all journals * Search * Log in * Explore content * About the journal * Publish with us * Sign up for alerts * RSS feed 1. nature 2. communications earth & environment 3. articles 4. article Sulfur fertiliser use in the Midwestern US increases as atmospheric sulfur deposition declines with improved air quality Download PDF Your article has downloaded Similar articles being viewed by others Carousel with three slides shown at a time. Use the Previous and Next buttons to navigate three slides at a time, or the slide dot buttons at the end to jump three slides at a time. [41561_2020] A shift in sulfur-cycle manipulation from atmospheric emissions to agricultural additions 10 August 2020 Eve-Lyn S. Hinckley, John T. Crawford, ... Charles T. Driscoll [41893_2018] Addressing agricultural nitrogen losses in a changing climate 14 August 2018 Timothy M. Bowles, Shady S. Atallah, ... A. Stuart Grandy [41612_2022] Addressing nitrogenous gases from croplands toward low-emission agriculture 02 June 2022 Shu-Yuan Pan, Kung-Hui He, ... Chang-Tang Chang [41598_2022] Greenhouse gas emissions from global production and use of nitrogen synthetic fertilisers in agriculture 25 August 2022 Stefano Menegat, Alicia Ledo & Reyes Tirado [41597_2021] Crop production and nitrogen use in European cropland and grassland 1961-2019 29 October 2021 Rasmus Einarsson, Alberto Sanz-Cobena, ... Luis Lassaletta [41586_2022] Cost-effective mitigation of nitrogen pollution from global croplands 04 January 2023 Baojing Gu, Xiuming Zhang, ... Deli Chen [43016_2021] Global mapping of crop-specific emission factors highlights hotspots of nitrous oxide mitigation 21 October 2021 Xiaoqing Cui, Feng Zhou, ... Dongqiang Zhu [43016_2021] Quantification of global and national nitrogen budgets for crop production 15 July 2021 Xin Zhang, Tan Zou, ... Eric A. Davidson [43016_2020] Air quality, nitrogen use efficiency and food security in China are improved by cost-effective agricultural nitrogen management 14 October 2020 Yixin Guo, Youfan Chen, ... Denise L. Mauzerall Download PDF * Article * Open Access * Published: 23 December 2022 Sulfur fertiliser use in the Midwestern US increases as atmospheric sulfur deposition declines with improved air quality * Eve-Lyn S. Hinckley ORCID: orcid.org/0000-0002-7081-0530^1,2 & * Charles T. Driscoll ORCID: orcid.org/0000-0003-2692-2890^3 Communications Earth & Environment volume 3, Article number: 324 ( 2022) Cite this article * 329 Accesses * 29 Altmetric * Metrics details Subjects * Element cycles * Environmental impact Abstract Sulfur, as an essential nutrient for plant growth, has increasingly been used in fertiliser applications for many crops. This increase is coincident with declines in atmospheric sulfur deposition in response to air quality improvements in the United States and Europe. Here, we evaluate trends in sulfur fertiliser sales by mass, as a proxy for fertiliser applications, and estimate total atmospheric sulfur deposition across the Midwestern United States. Crop acreage, yield and sulfur fertiliser application substantially increased between 1985 and 2015, coincident with declines in atmospheric sulfur deposition. The increase in sulfur fertiliser has outpaced the relative rate of change in other major nutrient fertilisers including nitrogen, phosphorus and potassium, by approximately 7-fold prior to 2009, and 29-fold after 2009. We suggest that there is a critical need to develop sulfur management tools that optimize fertiliser applications to maintain crop yields while minimizing the consequences of excess sulfur in the environment. Introduction Management of nitrogen (N) and phosphorus (P) fertilisers has long been a concern in agricultural systems around the world, including the United States. Consequently, substantial agronomic research has focused on the timing and amounts of N and P applications to maximize yields while minimizing environmental impacts, including greenhouse gas emissions, soil degradation, and eutrophication of surface waters ^1,2,3,4. Like N and P, sulfur (S) is both a nutrient required for plant growth^5 and can have notable environmental consequences, as demonstrated by ecosystem studies of acid rain in the 1970s and 1980s, including acidification of soils and surface waters, mobilization of toxic metals, and others^6. Until recently, crop S demand has largely been met by historically high atmospheric S deposition^7. Yet with air quality changes due to regulation and shifts in energy generation, the free supply of S has declined in the U.S., Europe, and elsewhere (Fig. 1), requiring application of S fertilisers and/or release of legacy S stored in soils--the dynamics and magnitude of which are unknown--to meet plant demand (Fig. 1). This fundamental shift in human manipulation of the S cycle, from diffuse atmospheric inputs as a component of acid rain to targeted applications, necessitates a critical analysis of agricultural S loads, soil S dynamics, and associated environmental consequences^8. Fig. 1: Mass balance estimate of S in agriculture from 1985-2017. figure 1 a Conceptual model of S flows. b Trends in S inputs and estimated S output in maize. Areal loads are calculated as the total amount of S normalized by the total land area of the study region (atmospheric S deposition), the total cropland in the study region (all S fertiliser products), and area of maize planted (maize S). Best fit lines are slope = -0.12 kg S ha^-1 yr^-1, R^2 = 0.96 (atmospheric S deposition), 0.10 kg S ha^-1 yr^-1, R^2 = 0.82 (fertiliser S inputs), and slope = 0.06 kg S ha^-1 yr^-1, R^2 = 0.46 (maize S). The linear models are statistically significant (p < 0.001). The slopes of all regression lines are significantly different from zero (p < 0.0001). The mass balance estimate (i.e., atmospheric S deposition and fertiliser inputs less maize S export) is shown for reference. A negative value indicates that atmospheric S deposition plus fertiliser S application exceed losses from maize export. A positive value shows that atmospheric S deposition plus fertiliser S application does not compensate for losses from maize export. Full size image The Midwestern region of the U.S., which provides approximately one-third of global maize and soybean production^9, also experienced some of the highest rates of atmospheric S deposition derived from fossil fuel emissions prior to the Clean Air Act and Amendments^10. On one hand, elevated atmospheric S deposition--at its highest rate of ~20 kg S ha^-1 yr^-1 through the mid-1980s--met or exceeded the demand of major crops, like maize [Zea mays (L.)] (Fig. 1). However, increases in both the footprint and yields of maize and soybean [ Glycine max (L.) Merr.] in the region have driven increased crop S demand that must be met by sources other than atmospheric deposition^ 11 (Fig. 2). While there have been many efforts to study and improve the timing and efficiency of N and P applications across the Midwestern U.S. and other regional crop systems^12,13,14,15, comparable attention has not been given to characterizing the fate or optimization of agricultural S inputs. Fig. 2: Midwestern U.S. region maize and soybean. figure 2 a Map of the study area showing the crop acreage of maize and soybean in 2008 (yellow) and 2020 (red). b Maize and soybean yields from 1985 through 2021 in the study region. The target moisture contents of soybean, maize (grain), and maize (silage) at harvest are ~13%, 15%, and 65-70%, respectively. Best fit lines are slope = 0.03 MT ha^-1 yr ^-1, R^2 = 0.69 (soybean), slope = 0.12 MT ha^-1 yr^-1, R^2 = 0.75 (maize, grain), and slope = 0.53 MT ha^-1 yr^-1, R^2 = 0.71 (maize, silage). The linear models are statistically significant (p < 0.001). Only the slopes of maize (grain and silage) are statistically different from zero (p < 0.004). The base map shown in a is from^33. Full size image One challenge in determining the environmental and human health consequences of large-scale S applications in crop systems has been a lack of publicly available data from individual farmers and governments^8. While some U.S. states, such as California, have mandatory reporting of S pesticide applications^16, they are the exception. The U.S. Department of Agriculture (USDA) conducts periodic surveys of S and other fertilisers, but these are neither conducted annually nor are comprehensive across all crops. Here, we present a compiled dataset of S-containing fertilisers from the Association of American Plant Food Control Officials (AAPFCO), available from 1985-2015, and use it as a proxy for S inputs to Midwestern U.S. croplands. While the data are reported by mass sold and at the county level, we provide an analysis of trends across the Midwest region (12 states; Fig. 2a). The results are presented in aggregate, as we recognize that in some cases, fertiliser sales and application location are an imperfect match; large-scale growers may purchase products in one county (reported) and use them in another (unreported). We compare the trends in S fertiliser products, atmospheric S deposition, and estimated S exported in maize tissues using wet S deposition data from the National Atmospheric Deposition Program (NADP)^17, dry S deposition from the Clean Air Status and Trends Network (CASTNET)^18, and precipitation data from PRISM^19 (both NADP and CASTNET data are available starting in 1987); fertiliser product sales from AAPFCO; and annual crop acreage and yield data from USDA^20,21. In addition, we compared the trends in S fertiliser products to those of N, P, and K for the study region (data from AAPFCO). Results and discussion From 1987 to 2019, atmospheric S deposition declined at a rate of -0.12 kg S ha^-1 yr^-1, from 4.7 to 1.1 kg ha^-1 yr^-1, averaged across the Midwestern U.S. region (R^2 = 0.96, p < 0.0001; Fig. 1b). Today, atmospheric S deposition is close to background (i.e., pre-industrial) levels^22. Comparatively, all S-containing fertiliser products have increased at a rate of 0.10 kg S ha^-1 yr^-1, from 1.3 to 4.9 kg ha^-1 yr^-1 between 1985 and 2015, averaged over Midwestern croplands (R^2 = 0.82; p < 0.0001; Fig. 1b). Because S is added to crops not only as a primary fertiliser, but also as a carrier anion for other fertilisers (e.g., N), and the target crop is not reported in the AAPFCO dataset, we also evaluated the change in sulfur-S over the same period. When S was clearly the target nutrient added to crops (at > 85% S content), the increase over time was also significant (R^2 = 0.71; p < 0.0001; see Data Availability). The rate of change in average S fertiliser load is important to consider in the context of changes in other major fertilisers over the same period: N, P, and potassium (K). Indeed, the percent change shown as the anomaly relative to 1985 (Fig. 3) illustrates that all S-containing products, as well as sulfur-S, are increasing at a significantly faster rate than other major fertilisers (p < 0.0001). Over the period of record, N and P increased, yet the rates of change in all nutrients other than S were not significantly different from zero (p > 0.05; Fig. 3). Note the rate of change in S calculated with a best-fit linear regression underestimates the marked increase in S loads since 2009. For the period from 2009-2015, the relative change in all S products was 29.6% yr^-1 and sulfur-S was 21.1% yr^-1 (p < 0.006 and 0.04, respectively). This uptick in use may reflect farmers' recognition of the need to augment S inputs to account for the decline in atmospheric S deposition and insufficient S released from the soil organic pool. Fig. 3: Percent change in N, P, K, and S products relative to 1985. figure 3 The total load of each element was calculated based on the stoichiometry of the fertiliser products and the mass of each product sold. Best fit lines are slope = 0.7% change in N yr^-1, R^2 = 0.52; slope = 1.2% change in P yr^-1, R^2 = 0.62; slope = 0.1% change in K yr^-1, R^2 = 0.01; slope = 7.7% change in all S products yr^-1, R^2 = 0.82; and slope = 6.6% change in sulfur-S yr^-1, R^2 = 0.71. For the period from 2009-2015, the slopes of the trendlines for all S-containing products and sulfur-S are 29.6% yr^-1 (R^2 = 0.91 and p < 0.006) and 21.1% yr^-1 (R^2 = 0.55 and p < 0.04), respectively. All linear models are statistically significant (p < 0.001) except K (p = 0.52). The slopes of N, P, and K trends are significantly different from those of all S-containing and sulfur-S products (p < 0.0001); the trend in sulfur-S is not significantly different from that of all S containing products (p = 0.093). Only the slopes of all S products and sulfur-S are significantly different from zero (p < 0.0001). Full size image In addition to the decline in atmospheric S deposition, there are three other important factors that likely contribute to the increase in use of S fertiliser products across the Midwestern U.S. First, while total crop acreage has fluctuated from 1985-2020, maize and soybean have increasingly dominated the agricultural footprint of the region and expanded into the Upper Midwest^23,24;Fig. 2a. Maize yield has increased significantly (p < 0.004; Fig. 2b), creating both higher nutrient export in crop tissues and demand for more intensive fertiliser inputs. Other crops in the region include hay, winter wheat, sorghum, and oats^20. Sulfur fertiliser is added at notable rates to alfalfa hay, at ~45 kg ha^-1 yr^-1^25. However, by 2015, the combined footprint of hay and other secondary crops was <25% of the total crop acreage^20, indicating that they are likely to be a minor influence on fertiliser trends in this region. Yet, productivity of maize and soybean alone cannot explain the regional trends in S fertiliser use. Variability in S fertiliser sales records at finer, local scales may be driven by a second important factor: the distribution of soil S pools and spatial heterogeneity in S cycling and availability to plants (e.g., via mineralization of organic S). Along the Eastern Seaboard of North America, stream export of stored, legacy S has been higher in the northeastern U.S., which was previously glaciated, than in the southeastern U.S., which was not^26--a pattern controlled by soil properties associated with glaciation. We estimate that soil S pools in the Midwestern U.S. range from 0.002-2.3 kg S m^-2 (median value of 0.23 kg S m^-2) in the upper 0.9 m;^27,28 see Supplementary Note 2 , suggesting that there is a substantial S reservoir. While our quasi-mass balance of S in crop systems (Fig. 1b) indicates that more recently, inputs may meet crop S demand, this estimate is conservative. It does not account for S export in soybean (often double-cropped with maize) or riverine export of sulfate-S, which occurs at a rate higher than estimated S export in crop tissues^8. Elevated S losses from the Midwestern region compared with total S inputs highlights a critical need to investigate internal soil S cycling processes that regulate mobility and residence time. Factors like organic matter content, soil type and texture, and rates of mineralization will be an important component of sustainable S management plans. Currently, there does not exist temporal or spatially explicit data on soil S storage or process rates in regional crop systems like the Midwestern U.S (Fig. 1a). Finally, decision-making of individual farmers and management companies with respect to treating crop S deficiencies and other practices (e.g., tilling, buffer strips, irrigation, and use of other agriproducts) is another source of variability in regional trends. Our estimate of ~5 kg S ha^-1 yr^-1 (fertiliser S) is averaged over the entire crop acreage of the region (Fig. 2a). However, S inputs by individual farmers are variable, with far higher applications in some areas than others. In addition, trends in other fertiliser use, such as switching from ammonium nitrate to ammonium sulfate to supply N--a substantial nutrient addition to maize, for example, could affect S loading (see Supplementary Note 1 and Supplementary Fig. 1). Thus, the explanation for the broad trend in increasing S fertiliser use across the Midwestern U.S. is likely a combination of factors: declines in atmospheric S deposition, yield dynamics driven by climate and soil type, local soil S cycling rates, and management decisions. An integrated effort to quantify these components of the current, altered S cycle is an important next step to inform sustainable S management at local to regional scales. While our multiple lines of evidence suggest that use of targeted, S fertiliser applications was not widespread prior to the Clean Air Act and Amendments, we do not conclude that dirtier air is better for large-scale agriculture. Recent research^29 demonstrates that the benefits of air quality improvements to maize and soybean yields in the Midwest are substantial; namely, reduction in ozone, particulate matter, sulfur dioxide, and nitrogen dioxide. Rather, we argue that with air quality regulation and high agricultural productivity continuing as priorities not only in the U.S., but also in many parts of the world, the pressure to add S fertilisers will continue to increase. This shift in human manipulation of the S cycle--from fossil fuel emissions to agricultural inputs--requires a concerted effort to understand the dynamics of S released from the soil pool, as well as the long-term consequences of S applications for local and adjacent ecosystems^8. Lessons from studies of excess N and P fertilisers in the environment provide motivation to proactively investigate and address how to sustainably manage S additions in agriculture. Such efforts could yield benefits for major crops, ecosystems, and people around the world. Methods Compilation and analysis of fertiliser sales data We compiled fertiliser sales data from the Association of American Plant Food Control Officials (AAPFCO) for all years currently available (1985-2015)^30. Sales data (in pounds of each product purchased) are reported annually by farmers and aggregated at the county level. We separated all fertilisers into groups containing nitrogen (N), phosphorus (P), potassium (K), and sulfur (S), regardless of whether each nutrient was the target addition (e.g., N in ammonium sulfate) or a carrier (e.g., S in ammonium sulfate); we used this approach to calculate a total load of each nutrient for our study region. In some cases, the percentage N, P, K, and/or S was provided, while in others it was not. In the absence of reported nutrient content data, we calculated a range of possible values (low, average, and high) based on publicly available product information and/or published literature (see Data Availability). By multiplying the elemental content of a product by its total product mass sold per county, we calculated a mass of N, P, K, and S for each product per county per reporting period. It is possible that some products containing trace amounts of N, P, K, and S were not included in our analysis. However, these trace amounts would be a small amount of the total load, which is normalized over all cropland in the Midwestern U.S. region. Ultimately, products for which N, P, K, and/or S content was not reported in the AAPFCO dataset did not have appreciable differences in the calculated loads across the range of possible stoichiometric values and the trends were the same. Thus, we reported the loads based on the average reported content of each element in each fertiliser product. In addition, we found that the county-level data reporting was imperfect in some instances. For example, sometimes the data were reported for a state, but the county (FIPS) identifier was absent. We also recognized that large producers might purchase fertilisers in a different location (i.e., county) from where it was applied. Thus, we aggregated the data to evaluate trends across a 12-state region in the Midwest encompassing much of the maize and soybean cultivated in the U.S. Note that in cases when more fertiliser product was purchased than was used in a particular location over the course of the year, the unused mass was subtracted from the value in the following year. This resulted in reporting of some negative values year to year, reflecting a more accurate accounting of fertiliser sales over the entire period. To estimate area-normalized S loads, we divided the total weight of each fertiliser (N, P, K, S) by the total crop acreage data reported for each state by year from the USDA Economics, Statistics, and Market Information System^20. The total crop acreage includes area planted for maize, sorghum, oats, barley, rye, winter wheat, Durum wheat, other spring wheat, rice, soybean, peanuts, sunflower, cotton, dry edible beans, potatoes, sugar beets, canola, and proso millet. Hay, tobacco, and sugarcane are included as harvested acreage. These totals include double-cropped acres and unharvested small grains planted as cover crops. Again, crops other than maize and soybean were the minority (<25%) of the total acreage in the study region. To estimate S exported in maize tissues, we used tissue data reported by University of Nebraska-Lincoln Extension^31 and maize acres planted from the USDA NASS QuickStats database^21. It is important to recognize that this estimate is conservative; we do not have a time series of S content of maize tissues, nor do we include soybean, as we could not parse areas single- or double-cropped with maize. Finally, we estimated yield trends in soybean, maize (grain), and maize (silage) for the Midwest region using a combination of yield (quantity per acre) and acres harvested reported in the USDA NASS QuickStats database^21. Information on estimating soil S pools is provided in Supplementary Note 2. Estimation of atmospheric S deposition fluxes We estimated total atmospheric S deposition for the study region using annual volume-weighted sulfate concentrations in wet-only deposition measurements from the National Atmospheric Deposition Program (NADP)^17, estimates of dry S deposition from the U.S. Environmental Protection Agency Clean Air Status and Trends Network (CASTNET)^18 and precipitation quantity data from the PRISM spatial climate datasets^19. We interpolated total deposition for unmonitored regions using estimates at point locations. This analysis was accomplished using a spatial model that incorporates precipitation quantity, annual volume-weighted mean S concentrations in precipitation, and the dry deposition data for particulate sulfate and sulfur dioxide. The model then uses a Kriging approach to determine the spatial pattern of S concentration in precipitation from the network of NADP stations within the 12 Midwestern U.S. states included in this analysis. Similarly, we used Kriging to generate spatial patterns of dry S deposition using point data obtained from 14 sites monitored as part of the CASTNET program. The annual total S deposition was generated for each of 12 states for all individual years between 1989--the year when adequate point data were available through the networks to develop the Kriging models--and 2017. The overall uncertainty in flux estimates is comprised of multiple sources of uncertainty associated with the components of annual total S deposition. For wet S deposition there is uncertainty in the weekly measurements of precipitation volume, as well as sulfate concentrations; weekly measurements are summed to give annual fluxes of wet sulfate deposition. The quality assurance procedures for the NADP are summarized by the laboratory^17. For dry S deposition, there are uncertainties associated with the measurements of gaseous sulfur dioxide and particulate sulfate concentrations, as well as the modeled deposition velocity values to estimate deposition flux. Finally, there is uncertainty associated with the spatial extrapolation of point measurements from the deposition networks to the state scales. We estimated areal-normalized atmospheric S deposition using state areas for the Midwestern U.S. study region. Statistical analyses To evaluate the trends in atmospheric S deposition, maize and soybean yields, and fertiliser sales over time, we used the lm function in R^ 32 to determine the best-fit linear regression lines. We report slopes of the best-fit lines, as well as their R^2 and p-values. We also test the hypotheses that (1) trends in N, P, and K products are statistically different from the trend in S products (all S-containing products, and sulfur-S products only, p < 0.05) and (2) that the slopes of all regression lines are statistically different from zero (p < 0.05). Data availability All crop acreage, aggregated fertilizer sales by mass, and atmospheric sulfur deposition data are available through the Environmental Data Initiative web portal: Hinckley, E.S. 2022. Midwest U.S. Fertilizer Data, 1985-2015 ver 1. Environmental Data Initiative. https://doi.org/10.6073/pasta/ 2868799978abc180ff22ebc8da880248 (Accessed 2022-11-24). Relevant citations for additional datasets are provided in the References section. References 1. Bennett, E. M., Carpenter, S. R. & Caraco, N. F. Human impact on erodable phosphorus and eutrophication: a global perspective: increasing accumulation of phosphorus in soil threatens rivers, lakes, and coastal oceans with eutrophication. BioScience 51, 227-234 (2001). Article Google Scholar 2. Huang, J., Xu, C. C., Ridoutt, B. G., Wang, X. C. & Ren, P. A. Nitrogen and phosphorus losses and eutrophication potential associated with fertilizer application to cropland in China. J. Clean. Prod. 159, 171-179 (2017). Article Google Scholar 3. Schlesinger, W. H. On the fate of anthropogenic nitrogen. P. Natl. Acad. Sci. USA 106, 203-208 (2009). Article CAS Google Scholar 4. Tilman, D., Cassman, K. G., Matson, P. A., Naylor, R. & Polasky, S. Agricultural sustainability and intensive production practices. Nature 418, 671-677 (2002). Article CAS Google Scholar 5. Jez, J. Ed. Sulfur: A missing link between soils, crops, and nutrition (No. 50). ASA-CSSA-SSSA (2008). 6. Likens, G. E., Driscoll, C. T. & Buso, D. C. Long-term effects of acid rain: response and recovery of a forest ecosystem. Science 272, 244-246 (1996). Article CAS Google Scholar 7. Schnug, E. & Evans, E. J. Monitoring of the sulfur supply of agricultural crops in northern Europe. Phyton 32, 119-122 (1992). CAS Google Scholar 8. Hinckley, E. L. S., Crawford, J. T., Fakhraei, H. & Driscoll, C. T. A shift in sulfur-cycle manipulation from atmospheric emissions to agricultural additions. Nat. Geosci. 13, 597-604 (2020). Article CAS Google Scholar 9. Food and Agriculture Organization of the United Nations, FAO Statistical Databases 2021 available at: http://faostat.fao.org (Accessed July 2021). 10. Baumgardner, R. E., Lavery, T. F., Rogers, C. M. & Isil, S. S. Estimates of the atmospheric deposition of sulfur and nitrogen species: Clean Air Status and Trends Network, 1990- 2000. Environ. Sci. Technol. 36, 2614-2629 (2002). Article CAS Google Scholar 11. Basso, B., Shuai, G., Zhang, J. & Robertson, G. P. Yield stability analysis reveals sources of large-scale nitrogen loss from the U.S. Midwest. Sci. Rep.-U.K. 9, 1-9 (2019). Google Scholar 12. Tyler, P. J. & Peterson, E. W. The role of corn and soybean cultivation on nitrate export from Midwestern US agricultural watersheds. Environ. Earth Sci. 79, https://doi.org/10.1007/ s12665-020-08964-x (2020). 13. Matson, P. A., Naylor, R. & Ortiz-Monasterio, I. Integration of environmental, agronomic, and economic aspects of fertilizer management. Science 280, 112-115 (1998). Article CAS Google Scholar 14. Cassman, K. G., Dobermann, A. & Walters, D. T. Agroecosystems, nitrogen-use efficiency, and nitrogen management. Ambio 31, 132-140 (2002). Article Google Scholar 15. Roberts, T. L. & Johnston, A. E. Phosphorus use efficiency and management in agriculture. Res. Conserv. Recycl. 105, 275-281 (2015). Article Google Scholar 16. California Department of Pesticide Regulation. https:// www.cdpr.ca.gov/ (Accessed July 2021). 17. National Atmospheric Deposition Program. http://nadp.slh.wisc.edu / (Accessed July 2021). 18. Clean Air Status and Trends Network. https://www.epa.gov/castnet (Accessed July 2021). 19. PRISM Climate Group. https://prism.oregonstate.edu/ (Accessed July 2021) 20. USDA Economics, Statistics, and Market Information System. https: //usda.library.cornell.edu/concern/publications/j098zb09z (Accessed July 2021) 21. USDA National Agricultural Statistics Service. https:// www.nass.usda.gov/Data_and_Statistics/ (Accessed July 2021). 22. Galloway, J. N., Likens, G. E., Keene, W. C. & Miller, J. M. The composition of precipitation in remote areas of the world. J. Geophys. Res.-Oceans. 87, 8771-8786 (1982). Article CAS Google Scholar 23. Wang, S., Di Tommaso, S., Deines, J. M. & Lobell, D. B. Mapping twenty years of corn and soybean across the US Midwest using the Landsat archive. Sci. Data. 7, 1-14 (2020). Article Google Scholar 24. Zhang, X., Lark, T. J., Clark, C. M., Yuan, Y. & LeDuc, S. D. Grassland-to-cropland conversion increased soil, nutrient, and carbon losses in the US Midwest between 2008 and 2016. Environ. Res. Let. 16, 054018 (2021). Article CAS Google Scholar 25. Camberato, J., Maloney, S., Casteel, S. & Johnson, K. Sulfur deficiency in alfalfa. https://www.agry.purdue.edu/ext/ soilfertility/05-03-12Sulfur_deficiency_alfalfa.pdf. (URL accessed August 2021). 26. Rice, K. C., Scanlon, T. M., Lynch, J. A. & Cosby, B. J. Decreased atmospheric sulfur deposition across the southeastern US: When will watersheds release stored sulfate? Environ. Sci. Technol. 48, 10071-10078 (2014). Article CAS Google Scholar 27. Smith, D. B. et al. Geochemical and mineralogical data for soils of the conterminous United States. U.S. Geol. Surv. Data Ser. 2013 801, 1-26 (2013). Google Scholar 28. Olson, C. I. et al. Mercury in soils of the conterminous United States: patterns and pools. Environ. Res. Lett. 17, 074030 (2022). Article Google Scholar 29. Lobell, D. B. & Burney, J. A. Cleaner air has contributed one-fifth of US maize and soybean yield gains since 1999. Environ. Res. Lett., 16, https://doi.org/10.1088/1748-9326/ac0fa4 (2021). 30. Association of American Plant Food Control Officials (Online: https://www.aapfco.org/). 31. University of Nebraska-Lincoln. Farm and acreage--sulfur deficiency in corn. https://newsroom.unl.edu/announce/ lancasterextension/9974/59326. (URL accessed June 2022). 32. R Core Team. R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. https://www.R-project.org/ (URL Accessed August 2021). 33. U.S. Census Bureau. https://www2.census.gov/geo/tiger/TIGER2022/ STATE/ (URL Accessed August 2021). Download references Acknowledgements This research was supported by National Science Foundation CAREER Award (EAR-1945388) to E.S.H. We appreciate the help of H. Fakhraei with the calculations of atmospheric S deposition, C. Olson with calculation of soil S pools, and J. Pierson with the preparation of Fig. 1a. E.S.H. thanks University of Colorado, Boulder's RIO Faculty Fellows Program for time to prepare this manuscript. Author information Authors and Affiliations 1. Cooperative Institute for Research in Environmental Sciences, Boulder, CO, USA Eve-Lyn S. Hinckley 2. Department of Ecology and Evolutionary Biology, University of Colorado at Boulder, Boulder, CO, USA Eve-Lyn S. Hinckley 3. Civil and Environmental Engineering, Syracuse University; Syracuse, New York, NY, USA Charles T. Driscoll Authors 1. Eve-Lyn S. Hinckley View author publications You can also search for this author in PubMed Google Scholar 2. Charles T. Driscoll View author publications You can also search for this author in PubMed Google Scholar Contributions E.S.H. and C.T.D. jointly conceptualized the study and designed the analyses. ESH conducted the analyses, created the visuals, and wrote the original draft. C.T.D. reviewed and edited subsequent drafts. Corresponding author Correspondence to Eve-Lyn S. Hinckley. Ethics declarations Competing interests The authors declare no competing interests. Peer review Peer review information Communications Earth & Environment thanks Lawrence Aula and the other, anonymous, reviewer(s) for their contribution to the peer review of this work. Primary Handling Editors: Clare Davis. Additional information Publisher's note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. Supplementary information Supplementary Information Rights and permissions Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. Reprints and Permissions About this article Verify currency and authenticity via CrossMark Cite this article Hinckley, EL.S., Driscoll, C.T. Sulfur fertiliser use in the Midwestern US increases as atmospheric sulfur deposition declines with improved air quality. Commun Earth Environ 3, 324 (2022). https: //doi.org/10.1038/s43247-022-00662-9 Download citation * Received: 27 November 2021 * Accepted: 14 December 2022 * Published: 23 December 2022 * DOI: https://doi.org/10.1038/s43247-022-00662-9 Share this article Anyone you share the following link with will be able to read this content: Get shareable link Sorry, a shareable link is not currently available for this article. Copy to clipboard Provided by the Springer Nature SharedIt content-sharing initiative Comments By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate. Download PDF Advertisement Advertisement Explore content * Research articles * Reviews & Analysis * News & Comment * Collections * Follow us on Twitter * Sign up for alerts * RSS feed About the journal * Aims & Scope * Journal Information * Open Access * Journal Metrics * Editors * Editorial Board * Referees * Editorial Values Statement * Editorial policies * Conferences * Contact * Calls for Papers Publish with us * For authors * Language editing services * Submit manuscript Search Search articles by subject, keyword or author [ ] Show results from [All journals] Search Advanced search Quick links * Explore articles by subject * Find a job * Guide to authors * Editorial policies Communications Earth & Environment (Commun Earth Environ) ISSN 2662-4435 (online) nature.com sitemap About Nature Portfolio * About us * Press releases * Press office * Contact us Discover content * Journals A-Z * Articles by subject * Nano * Protocol Exchange * Nature Index Publishing policies * Nature portfolio policies * Open access Author & Researcher services * Reprints & permissions * Research data * Language editing * Scientific editing * Nature Masterclasses * Nature Research Academies * Research Solutions Libraries & institutions * Librarian service & tools * Librarian portal * Open research * Recommend to library Advertising & partnerships * Advertising * Partnerships & Services * Media kits * Branded content Career development * Nature Careers * Nature Conferences * Nature events Regional websites * Nature Africa * Nature China * Nature India * Nature Italy * Nature Japan * Nature Korea * Nature Middle East * Privacy Policy * Use of cookies * Manage cookies/Do not sell my data * Legal notice * Accessibility statement * Terms & Conditions * California Privacy Statement Springer Nature (c) 2023 Springer Nature Limited Close Nature Briefing Sign up for the Nature Briefing newsletter -- what matters in science, free to your inbox daily. Email address [ ] Sign up [ ] I agree my information will be processed in accordance with the Nature and Springer Nature Limited Privacy Policy. Close Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing * *