Quantitative soil profile-scale assessment of the sustainability of long-term maize residue and tillage management

application/pdfBoth surface and subsoil layers can be a significant source of soil moisture and nutrients for crop growth, but the changes in subsoil properties due to management are rarely assessed. This study was conducted to determine tillage and residue management effects on soil nutrient availability, as well as soil biological and physical conditions throughout soil layers ranging from 0 to 60?cm. We utilized an experiment with 40-year long continuous maize (Zea mays L.) cropping under crossed plow-till (PT) vs. no-till (NT) and residue removed (Harv) vs. residue returned (Ret) treatments on a silt loam soil in Chazy, NY. We assessed soil properties that are indicative of soil processes important for crop growth. Soil physical indicators (texture, bulk density (BD), water stable aggregation (WSA), available water capacity (AWC), and air-filled porosity (AFP)), soil biological indicators (soil organic matter (SOM), permanganate oxidizable carbon, mineralizable carbon, and soil protein), and soil chemical indicators (pH and plant available nutrients) were measured at five depth increments (0?6, 6?18, 18?30, 30?45, and 45- to 60-cm depth). A novel statistical approach of marginal R2 (R2m) was used to show percent variance of each measured soil indicator explained by tillage and residue management as well as the depth of soil sample. R2m was higher for soil biological indicators (0.66?<?R2m?<?0.91), compared to AWC and those nutrients that are not applied through fertilizer application (0.11?<?R2m?<?0.53). NT-Ret showed the highest concentration of majority of the measured soil nutrients, and higher accumulation of SOM related properties across depths. This was partly explained by favorable soil physical conditions indicated by BD, WSA, and AFP at the transition layer (18- to 30-cm depth) that allowed for the vertical exchange of soil water, nutrients, and SOM related properties between the topsoil and the subsoil layers. The PT treatments showed the absence of SOM transfer across the transition layer, whereas NT-Harv showed nutrient depletion at the transition and subsoil layers. This study revealed significant alteration of soil biological, chemical, and physical indicators depending on the treatment combinations, which can be ignored if surface sampling is solely used. Benefits of residue return appear more significant when combined with no-till for 1) providing better soil physical conditions and 2) maintaining adequate nutrient availability across a soil profile especially when considering subsoil properties. c 2017 Elsevier B.V.journal articl

Fluoride Catalysts and Organic Additives for Conversion of CO2 to Formic Acid and Methanol using Powdered Silicon as Reducing Agent

The effect of fluoride catalysts and organoboronic acid additives on the reduction of CO2 using waste silicon wafer powder as a reducing agent was investigated. Compared to other fluorides containing monovalent cations, tetraalkylammonium fluorides show higher catalytic activity for the conversion of CO2 to formic acid. Arylboronic acid containing electron-withdrawing groups such as p-fluorophenylboronic acid facilitated methanol formation during CO2 reduction. Electrophilic activation of formic acid by arylboronic acid may promote the reduction of formic acid to methanol.journal articl

育児期女性のライフコース展望に関連する要因の検討

departmental bulletin pape

A heterogeneous Pd complex catalyst for allylation with allylic alcohols enhanced by an aluminum-doped mesoporous silica support

Allylation using allylic alcohols is environmentally friendly because water is the only by-product. Allylic alcohols are one of the most unreactive allylating agents for homogeneous Pd-catalyzed allylation; however, they can undergo electrophilic activation with acidic active species. Heterogeneous catalysts are known for their unique catalytic performance due to the concerted effect of the immobilized metal center and support material surface. Our group has developed a mesoporous-silica-supported Pd complex catalyst that promotes the Tsuji-Trost allylation of dicarbonyl compounds with allylic alcohols through the concerted effect of Pd and surficial silanol groups. In this work, to enhance the catalytic activity of the supported Pd complex for allylation with allylic alcohols, the acidity of the support was increased by doping the silicate backbone with aluminum. Several spectroscopic techniques, such as Pd K-edge X-ray absorption fine structure (XAFS), solid-state NMR, and pyridine adsorption FT-IR measurements, were applied to confirm the structure of the catalyst. The Pd complex catalyst immobilized on an Al-doped support showed enhanced catalytic activity in allylation owing to the activation of the allylic alcohol by both the Al Lewis acid sites and silanol groups. The site-selective immobilization of the Pd complex through a silane-coupling reaction on Bronsted acid sites (Si-O(H+)-Al) enhances the concerted effect between the Pd complex and Lewis acidic Al sites on the MS surface.journal articl

川崎市多摩区住民の生活と福祉に関する意識調査 : 調査結果中間報告

departmental bulletin pape

Mobile Mechanism of the Wall-Climbing Robot using Thrust Force of Propeller and a Result of Outdoor Tests

Four quite different types of wall-climbing robot model have been developed in our laboratory. The third type can move speedy on a wall by using the thrust force of propellers and the drive force of wheels. In this paper following articles are briefly described, 1) Outline of the third type of wall-climbing robot 2) Propulsive force and wheel drive controller 3) Pilot assist radio control system 4) A result of outdoor testsconference pape

A mechanism for moving over obstacles on an wall for the wall-climbing vehicles of wheel-drive type

A wall-driving robot was developed in 1994 in our laboratory, and it could move on a vertical wall by using thrust force of two propellers and wheels. This model is easily controlled on a flat wall, but was difficult to use on an irregular wall. To solve this problem, the mechanism of wall-climbing of this type was simulated on a computer, and particular attention was paid to and maneuverability in the movement of this robot. A test model is manufactured and the experiments confirm that the model can move on an irregular wall by using a computer-aided control system.conference pape

Studies on Water Pollution and Aquatic Insects in the Takahashi River Part I

departmental bulletin pape

Physiological response during a novel circuit weight training “CrossFit-style” protocol for Judo competitors

原著論文departmental bulletin pape

A Technical Outlook for the Mobility of Propeller Type Wall-Climbing Robot

Three quite different types of wall-climbing robot models have been developed in our laboratory. The 3rd type can move on a wall by using the thrust force of propellers. A Technical outlook for the mobility of this model is discussed in this paper.conference pape