The carbon-isotopic composition (delta13C) of soil-respired CO2 has been employed to evaluate soil carbon-cycling processes and the contribution of soil CO2 emissions to canopy and tropospheric air. These evaluations can be successful only when accurate isotope values of soil-respired CO2 are available. Here, we tested the robustness of delta13C values of soil-respired CO2 obtained after long i...

A linear inversion scheme for microwave imaging of buried objects is presented in which arbitrary antennas are accounted for through their plane-wave transmitting and receiving spectra. INTRODUCTION Ground penetrating radar (GPR) is an efficient tool for microwave imaging of buried objects. Within the concept of diffraction tomography, as proposed by Devaney [1], several linear inversion scheme...

Physical protection of soil carbon (C) is one of the important components of C storage. However, its exact mechanisms are still not sufficiently lucid. The goal of this study was to explore the influence of soil structure, that is, soil pore spatial arrangements, with and without presence of plant residue on (i) decomposition of added plant residue, (ii) CO2 emission from soil, and (iii) struct...

Vapor intrusion (VI) has been recognized since the 1990s as a potential pathway of concern at contaminated sites. VI is the migration of volatile organic compounds (VOCs) from the subsurface soils into overlying buildings. The major sources of organic vapors are waste disposal sites (landfills), contaminated old industrial sites, contaminated subsurface soils, and contaminated groundwater. The ...

The carbon (C) storage capacity of northern latitude ecosystems may diminish as warming air temperatures increase permafrost thaw and stimulate decomposition of previously frozen soil organic C. However, warming may also enhance plant growth so that photosynthetic carbon dioxide (CO2) uptake may, in part, offset respiratory losses. To determine the effects of air and soil warming on CO2 exchang...

Local emissions of SF6 are of interest for studying their impact on the use of SF6 as a groundwater-dating tool near source regions as well as for investigating the spatial distributions of (inert) gaseous compounds spreading from urban or industrial centers. A precondition for the use of SF6 in such studies is the capability to document the temporal and spatial evolution of SF6 in and around s...

Winter cover crops are sources of C and N in flooded rice production systems, but very little is known about the effect of crop residue management and quality on soil methane (CH4) and nitrous oxide (N2O) emissions. This study was conducted in pots in a greenhouse to evaluate the influence of crop residue management (incorporated into the soil or left on the soil surface) and the type of cover-...

Winter wheat–summer fallow is the conventional cropping system employed on >1·5 million ha within the Columbia Plateau of eastern Washington and northern Oregon. Wind erosion contributes to poor air quality in the region, yet little is known concerning the magnitude of soil and PM10 (particulate matter of ≤10 μm in aerodynamic diameter) loss from agricultural lands. Therefore, loss of soil and ...

depth of frost penetration is one of the main indices in agriculture, civil and transportation engineering. soil temperature is a function of several factors including: topography, solar radiation, air temperature, moisture content and other physical properties of soil such as thermal capacity, coefficient of heat conductivity, and specific heat. the main objective of the present paper is to de...