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Full-Text Articles in Engineering
Moisture Insensitive Prediction Of Soil Properties From Vnir Reflectance Spectra Based On External Parameter Orthogonalization, Nuwan K. Wijewardane, Yufeng Ge, Cristine L.S. Morgan
Moisture Insensitive Prediction Of Soil Properties From Vnir Reflectance Spectra Based On External Parameter Orthogonalization, Nuwan K. Wijewardane, Yufeng Ge, Cristine L.S. Morgan
Department of Biological Systems Engineering: Papers and Publications
Moisture is the single most important factor that affects soil reflectance spectra, particularly for field applications. Interest in using soil VNIR spectral libraries, which are commonly based on dry ground soils, to predict soils in the intact field-moist condition (in situ VNIR) is growing. External parameter orthogonalization (EPO) has been proposed as a useful method that links dry ground VNIR models to field moist scans. The goal of this study is to test EPO on a wider set of soil properties and four different modeling techniques, namely, Partial Least Squares Regression (PLS), Artificial Neural Network (ANN), Random Forest (RF), and …
Effects Of Calcium Silicate Treatment On The Composition Of Forest Floor Organic Matter In A Northern Hardwood Forest Stand, Ankit Balaria, Chris E. Johnson, Peter M. Groffman, Melany C. Fisk
Effects Of Calcium Silicate Treatment On The Composition Of Forest Floor Organic Matter In A Northern Hardwood Forest Stand, Ankit Balaria, Chris E. Johnson, Peter M. Groffman, Melany C. Fisk
Civil and Environmental Engineering
Calcium amendment can help improve forest sustainability in stands that have been impacted by chronic acid deposition. An important component of this improvement is the stimulation of the microbial activity that supports ecosystem nutrient cycling processes. To test the hypothesis that Ca treatment alters the structure and solubility of organic matter substrates, an important driver of microbial activity, we investigated the effect of wollastonite (CaSiO3) treatment on soil organic matter (SOM) and hot-water-extractable organic matter (HWEOM). We found a decrease in the HWEOM content of forest floor soils within two years of treatment with a high dosage of …
Effects Of Calcium Treatment On Forest Floor Organic Matter Composition Along An Elevation Gradient, Ankit Balaria, Chris E. Johnson, Peter M. Groffman
Effects Of Calcium Treatment On Forest Floor Organic Matter Composition Along An Elevation Gradient, Ankit Balaria, Chris E. Johnson, Peter M. Groffman
Civil and Environmental Engineering
Calcium amendment is a restorative option for nutrient-depleted, acidic soils in the forests of the northeastern United States. We studied the effects of watershed-scale wollastonite (CaSiO3) application on the structural composition of soil organic matter (SOM) and hot-water extractable organic matter (HWEOM) at the Hubbard Brook Experiment Forest in New Hampshire 7-9 years after treatment, along an elevation gradient. Soils in the high-elevation spruce/fir/birch (SFB) zone contained significantly greater amounts of HWEOM compared to lower elevation hardwood soils, likely due to differences in litter quality and slower decomposition rates in colder soils at higher elevation. The only significant …
Uncertainties In Life Cycle Greenhouse Gas Emissions From U.S. Beef Cattle, Quentin M. Dudley, Adam Liska, Andrea K. Watson, Galen E. Erickson
Uncertainties In Life Cycle Greenhouse Gas Emissions From U.S. Beef Cattle, Quentin M. Dudley, Adam Liska, Andrea K. Watson, Galen E. Erickson
Adam Liska Papers
Beef cattle feedlots are estimated to contribute 26% of U.S. agricultural greenhouse gas (GHG) emissions, and future climate change policy could target reducing these emissions. Life cycle assessment (LCA) of GHG emissions from U.S. grain-fed beef cattle was conducted based on industry statistics and previous studies to identify the main sources of uncertainty in these estimations. Uncertainty associated with GHG emissions from indirect land use change, pasture soil emissions (e.g. soil carbon sequestration), enteric fermentation from cattle on pasture, and methane emissions from feedlot manure, respectively, contributed the most variability to life cycle GHG emissions from beef production. Feeding of …
Soil Mercury And Its Response To Atmospheric Mercury Deposition Across The Northeastern United States, Xue Yu, Charles T. Driscoll, Richard A. F. Warby, Mario Montesdeoca, Chris E. Johnson
Soil Mercury And Its Response To Atmospheric Mercury Deposition Across The Northeastern United States, Xue Yu, Charles T. Driscoll, Richard A. F. Warby, Mario Montesdeoca, Chris E. Johnson
Civil and Environmental Engineering
Terrestrial soil is a large reservoir of atmospherically deposited mercury (Hg). However, few studies have evaluated the accumulation of Hg in terrestrial ecosystems in the northeastern United States, a region which is sensitive to atmospheric Hg deposition. We characterized Hg and organic matter in soil profiles from 139 sampling sites for five subregions across the northeastern United States and estimated atmospheric Hg deposition to these sites by combining numerical modeling with experimental data from the literature. We did not observe any significant relationships between current net atmospheric Hg deposition and soil Hg concentrations or pools, even though soils are a …