From complex histories to cohesive data, a long-term agricultural dataset from the Morrow Plots.

Long-term agricultural experiments are essential to measure the impacts of farming practices on crop yields, soil fertility and biogeochemical processes. However, these impacts often only manifest at decadal timescales, requiring committed and consistent data collection that exceeds the timelines for most experiments. The second oldest agricultural experiment in the world, the Morrow Plots at University of Illinois Urbana-Champaign (USA) has examined the impact of crop rotation and fertility treatments on maize (Zea mays L.

Phosphorus dynamics across a 450 ka vertical chronosequence of loess derived (paleo)soils in central US.

Pedogenesis entails profound changes in terrestrial phosphorus (P) dynamics, yet means to understand how time- and climate-induced soil weathering impacts P-cycling over geologic timescales remain relatively limited to space-for-time substitution approaches with multi-site chronosequences. We tested an alternative approach for evaluating terrestrial P dynamics described by the Walker-Syers model by measuring P pools in a ~ 450 ka loess-paleosol sequence. This vertical chronosequence reflects episodic proglacial loess deposition during multiple glaciations and interglacial soil development in central North America in a four-stage loess-paleosol sequence that initiated with the pre-Illinois Episode glaciation.

Missing phosphorus legacy of the Anthropocene: Quantifying residual phosphorus in the biosphere.

A defining feature of the Anthropocene is the distortion of the biosphere phosphorus (P) cycle. A relatively sudden acceleration of input fluxes without a concomitant increase in output fluxes has led to net accumulation of P in the terrestrial-aquatic continuum. Over the past century, P has been mined from geological deposits to produce crop fertilizers.

Linking the humification of organic amendments with size aggregate distribution: Insights into molecular composition using FT-ICR-MS.

Soil organic matter (SOM) plays a pivotal role in enhancing physical and biological characteristics of soil. Humic substances constitute a substantial proportion of SOM and their increase can improve crop yields and promote agricultural sustainability. While previous research has primarily assessed the influence that humic acids (HAs) derived from natural water have on soil structure, our study focuses on the impact of HAs on soil aggregation under different fertilizer regimes.

Soil phosphorus cycling across a 100-year deforestation chronosequence in the Amazon rainforest.

Deforestation of tropical rainforests is a major land use change that alters terrestrial biogeochemical cycling at local to global scales. Deforestation and subsequent reforestation are likely to impact soil phosphorus (P) cycling, which in P-limited ecosystems such as the Amazon basin has implications for long-term productivity. We used a 100-year replicated observational chronosequence of primary forest conversion to pasture, as well as a 13-year-old secondary forest, to test land use change and duration effects on soil P dynamics in the Amazon basin.

Muddied Waters: The Use of "Residual" And "Legacy" Phosphorus.

Phosphorus (P) inputs to the biosphere have quadrupled in less than a century due to intensification of rock phosphate mining and the use of P fertilizers for crop production. Accumulation of P in soils can increase P transfers across the soil-water continuum that impair aquatic ecosystem function and water resource quality for society. However, what this accumulated P is called, and subsequent connotations of magnitude versus mechanism at pedon versus watershed scale, varies in the literature.

Field-scale evaluation of struvite phosphorus and nitrogen leaching relative to monoammonium phosphate.

Struvite (MgNH PO ·6H O) is a wastewater-derived phosphorus (P) fertilizer with potential to reduce P as well as nitrogen (N) losses due to its low water solubility. To test hypothesized lower P and N losses from struvite relative to monoammonium phosphate (MAP), field experiments with a randomized-complete block design were conducted in central (Urbana) Illinois on an Endoaquoll-Argiudoll complex and in southern (Ewing) Illinois on a Fragiudalf-Hapludalf complex. Fertilizer was broadcast applied in the fall prior to spring planting of soybean (Glycine max L.

Streambank erosion and phosphorus loading to surface waters: Knowns, unknowns, and implications for nutrient loss reduction research and policy.

To monitor and meet water quality objectives, it is necessary to understand and quantify the contribution of nonpoint sources to total phosphorus (P) loading to surface waters. However, the contribution of streambank erosion to surface water P loads remains unclear and is typically unaccounted for in many nutrient loading assessments and policies. As a result, agricultural contributions of P are overestimated, and a potentially manageable nonpoint source of P is missed in strategies to reduce loads.

Assessing long-term impacts of cover crops on soil organic carbon in the central US Midwestern agroecosystems.

Cover crops have been reported as one of the most effective practices to increase soil organic carbon (SOC) for agroecosystems. Impacts of cover crops on SOC change vary depending on soil properties, climate, and management practices, but it remains unclear how these control factors affect SOC benefits from cover crops, as well as which management practices can maximize SOC benefits. To address these questions, we used an advanced process-based agroecosystem model, ecosys, to assess the impacts of winter cover cropping on SOC accumulation under different environmental and management conditions.

From prairie to crop: Spatiotemporal dynamics of surface soil organic carbon stocks over 167 years in Illinois, U.S.A.

Quantifying spatiotemporal dynamics of soil organic carbon (SOC) stocks is needed to understand the impact of land use change and can help target carbon sequestration efforts. In the recently and radically transformed landscapes of the state of Illinois, U.S.

Fruit lead concentrations of tomato (Solanum lycopersicum L.) grown in lead-contaminated soils are unaffected by phosphate amendments and can vary by season, but are below risk thresholds.

Urban agriculture in post-industrial cities faces concerns on human health risks posed by elevated lead (Pb) concentrations of edible plant tissues grown in Pb-enriched soils. A recommended mitigation strategy to decrease soil Pb bioavailability to humans is the addition of soluble phosphate (PO-P), but it is unclear if this strategy can also reduce crop Pb uptake and accumulation in edible tissues. Across urban agriculture sites in Chicago, Illinois (6 site-years) with elevated total soil Pb, we tested the hypothesized decrease in tomato fruit Pb following soil-based application of three phosphate-based mitigation amendments: triple superphosphate, composted biosolids, and air dried biosolids.

Drivers of cadmium accumulation in Theobroma cacao L. beans: A quantitative synthesis of soil-plant relationships across the Cacao Belt.

Elevated cadmium (Cd) concentrations in cacao and cocoa-based products (e.g., chocolate) present a potentially serious human health risk.

Entrepreneurial Talent Building for 21st Century Agricultural Innovation.

Agricultural innovation is a key component of the global economy and enhances food security, health, and nutrition. Current innovation efforts focus mainly on supporting the transition to sustainable food systems, which is expected to harness technological advances across a range of fields. In this Nano Focus, we discuss how such efforts would benefit from not only supporting farmer participation in deciding transition pathways but also in fostering the interdisciplinary training and development of entrepreneurial-minded farmers, whom we term "AgTech Pioneers", to participate in cross-sector agricultural innovation ecosystems as cocreators and informed users of developing and future technologies.

Re-Envisioning Sanitation As a Human-Derived Resource System.

Sanitation remains a global challenge, both in terms of access to toilet facilities and resource intensity (e.g., energy consumption) of waste treatment.

Toward a Regional Phosphorus (Re)cycle in the US Midwest.

Redirecting anthropogenic waste phosphorus (P) flows from receiving water bodies to high P demand agricultural fields requires a resource management approach that integrates biogeochemistry, agronomy, engineering, and economics. In the US Midwest, agricultural reuse of P recovered from spatially colocated waste streams stands to reduce point-source P discharges, meet agricultural P needs, and-depending on the speciation of recovered P-mitigate P losses from agriculture. However, the speciation of P recovered from waste streams via its chemical transformation-referred to here as recovered P (rP) differs markedly based on waste stream composition and recovery method, which can further interact with soil and crop characteristics of agricultural sinks.

Aligning Product Chemistry and Soil Context for Agronomic Reuse of Human-Derived Resources.

Recovering human-derived nutrients from sanitation systems can offset inorganic fertilizer use and improve access to agricultural nutrients in resource-limited settings, but the agronomic value of recovered products depends upon product chemistry and soil context. Products may exacerbate already-compromised soil conditions, offer benefits beyond nutrients, or have reduced efficacy depending on soil characteristics. Using global spatial modeling, we evaluate the soil suitability of seven products (wastewater, sludge, compost, urine, ammonium sulfate, ammonium struvite, potassium struvite) and integrate this information with local recovery potential of each product from sanitation systems that will need to be installed to achieve universal coverage (referred to here as "newly-installed sanitation").

Improving Infrared Spectroscopy Characterization of Soil Organic Matter with Spectral Subtractions.

Soil organic matter (SOM) underlies numerous soil processes and functions. Fourier transform infrared (FTIR) spectroscopy detects infrared-active organic bonds that constitute the organic component of soils. However, the relatively low organic matter content of soils (commonly < 5% by mass) and absorbance overlap of mineral and organic functional groups in the mid-infrared (MIR) region (4,000-400 cm) engenders substantial interference by dominant mineral absorbances, challenging or even preventing interpretation of spectra for SOM characterization.

Application of DRIFTS, C NMR, and py-MBMS to Characterize the Effects of Soil Science Oxidation Assays on Soil Organic Matter Composition in a Mollic Xerofluvent.

Chemical oxidations are routinely employed in soil science to study soil organic matter (SOM), and their interpretation could be improved by characterizing oxidation effects on SOM composition with spectroscopy. We investigated the effects of routinely employed oxidants on SOM composition in a Mollic Xerofluvent representative of intensively managed agricultural soils in the California Central Valley. Soil samples were subjected to oxidation by potassium permanganate (KMnO), sodium hypochlorite (NaOCl), and hydrogen peroxide (HO).