Real-Time Sensing of Soil Nitrate Concentration in the Parts per Million Range While the Soil Is in Motion

Reactive nitrogen (Nr) is a term used to describe non-nitrogen gas (non-N2) forms of nitrogen (N) in the biosphere. It causes major pollution problems when it occurs in excess, and it has many sources, including fertilizers used in production agriculture. Currently there is no on-the-go soil nitrate sensor that could guide the application of the optimal amount of fertilizer, which often varies significantly within a field. We report for the first time nitrate-in-soil measurements performed on moving soil samples at concentration levels relevant for fertilizer application. An infrared emission technique called transient infrared spectroscopy (TIRS) was tested on soil samples spiked with different nitrate concentrations in the parts-per-million range and moving at a velocity of 2.6 m/s (5.8 miles per hour) in the laboratory. The TIRS Fourier transform infrared (FT-IR) spectra were modeled by partial least squares and produced a standard error of cross-validation (SECV) of 6.3 parts per million (ppm) N and an R 2 of 0.938 for 512-scan spectra. These results are compared to those using fewer TIRS scans and to those from photoacoustic spectroscopy (PAS) and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) measurements on stationary samples. TIRS 128-, 32-, and 8-scan spectra yielded SECVs of 11.2, 11.4, and 18.4 ppm N and R 2 values of 0.800, 0.831, and 0.583, respectively. The PAS and DRIFTS measurements produced SECVs of 12.4 and 9.0 ppm N and R 2 values of 0.766 and 0.876, respectively

Soil carbon increased by twice the amount of biochar carbon applied after six years: Field evidence of negative priming

Applying biochar to agricultural soils has been proposed as a means of sequestering carbon (C) while simultaneously enhancing soil health and agricultural sustainability. However, our understanding of the long‐term effects of biochar and annual versus perennial cropping systems and their interactions on soil properties under field conditions is limited. We quantified changes in soil C concentration and stocks, and other soil properties 6 years after biochar applications to corn (Zea mays L.) and dedicated bioenergy crops on a Midwestern US soil. Treatments were as follows: no‐till continuous corn, Liberty switchgrass (Panicum virgatum L.), and low‐diversity prairie grasses, 45% big bluestem (Andropogon gerardii), 45% Indiangrass (Sorghastrum nutans), and 10% sideoats grama (Bouteloua curtipendula), as main plots, and wood biochar (9.3 Mg/ha with 63% total C) and no biochar applications as subplots. Biochar‐amended plots accumulated more C (14.07 Mg soil C/ha vs. 2.25 Mg soil C/ha) than non‐biochar‐amended plots in the 0–30 cm soil depth but other soil properties were not significantly affected by the biochar amendments. The total increase in C stocks in the biochar‐amended plots was nearly twice (14.07 Mg soil C/ha) the amount of C added with biochar 6 years earlier (7.25 Mg biochar C/ha), suggesting a negative priming effect of biochar on formation and/or mineralization of native soil organic C. Dedicated bioenergy crops increased soil C concentration by 79% and improved both aggregation and plant available water in the 0–5 cm soil depth. Biochar did not interact with the cropping systems. Overall, biochar has the potential to increase soil C stocks both directly and through negative priming, but, in this study, it had limited effects on other soil properties after 6 years

Risky Business: Motivations for Markets in Programmable Networks

Abstract. We believe that the problems of safety, security and resource usage combine to make it unlikely that programmable networks will ever be viable without mechanisms to transfer risk from the platform provider to the user and the programmer. However, we have well established mechanisms for managing risk -markets. In this paper we argue for the establishment of markets to manage the risk in running a piece of software and to ensure that the risk is reflected on all the stakeholders. We describe a strawman architecture for third party computation in the programmable network. Within this architecture, we identify two major novel features:-Dynamic price setting, and a reputation service. We investigate the feasibility of these features and provide evidence that a practical system can indeed be built. Our contributions are in the argument for markets providing a risk management mechanism for programmable networks, the development of an economic model showing incentives for developing better software, and in the first analysis of a real transaction graph for reputation systems from an Internet commerce site

Lithium and aluminium carbamato derivatives of the utility amide 2, 2, 6, 6- tetramethylpiperidide

Insertion of CO2 into the metal-N bond of a series of synthetically-important alkali-metal TMP (2,2,6,6-tetramethylpiperidide) complexes has been studied. Determined by X-ray crystallography, the molecular structure of the TMEDA-solvated Li derivative shows a central 8-membered (LiOCO)2 ring lying in a chair conformation with distorted tetrahedral lithium centres. While trying to obtain crystals of a THF solvated derivative, a mixed carbonato/carbamato dodecanuclear lithium cluster was formed containing two central (CO3)2- fragments and eight O2CTMP ligands with four distinct bonding modes. A bisalkylaluminium carbamato complex has also been prepared via two different methods (CO2 insertion into a pre-formed Al-N bond and ligand transfer from the corresponding lithium reagent) which adopts a dimeric structure in the solid state

Soil carbon increased by twice the amount of biochar carbon applied after 6 years: Field evidence of negative priming

Applying biochar to agricultural soils has been proposed as a means of sequester-ing carbon (C) while simultaneously enhancing soil health and agricultural sustain-ability. However, our understanding of the long-term effects of biochar and annual versus perennial cropping systems and their interactions on soil properties under field conditions is limited. We quantified changes in soil C concentration and stocks, and other soil properties 6 years after biochar applications to corn (Zea mays L.) and dedicated bioenergy crops on a Midwestern US soil. Treatments were as fol-lows: no-till continuous corn, Liberty switchgrass (Panicum virgatum L.), and low-diversity prairie grasses, 45% big bluestem (Andropogon gerardii), 45% Indiangrass (Sorghastrum nutans), and 10% sideoats grama (Bouteloua curtipendula), as main plots, and wood biochar (9.3 Mg/ha with 63% total C) and no biochar applications as subplots. Biochar-amended plots accumulated more C (14.07 Mg soil C/ha vs. 2.25 Mg soil C/ha) than non-biochar-amended plots in the 0–30 cm soil depth but other soil properties were not significantly affected by the biochar amendments. The total increase in C stocks in the biochar-amended plots was nearly twice (14.07 Mg soil C/ha) the amount of C added with biochar 6 years earlier (7.25 Mg biochar C/ha), suggesting a negative priming effect of biochar on formation and/or mineralization of native soil organic C. Dedicated bioenergy crops increased soil C concentration by 79% and improved both aggregation and plant available water in the 0–5 cm soil depth. Biochar did not interact with the cropping systems. Overall, biochar has the potential to increase soil C stocks both directly and through negative priming, but, in this study, it had limited effects on other soil properties after 6 years