A5048564166- Soil and Unsaturated Flow
- Soil Geostatistics and Mapping
- Soil Carbon and Nitrogen Dynamics
- Geology and Paleoclimatology Research
- Soil erosion and sediment transport
- Landslides and related hazards
- Soil Moisture and Remote Sensing
- Groundwater flow and contamination studies
- Groundwater and Isotope Geochemistry
- Hydrology and Watershed Management Studies
- Aeolian processes and effects
- Soil and Water Nutrient Dynamics
- Remote Sensing and LiDAR Applications
- Clay minerals and soil interactions
- Atmospheric and Environmental Gas Dynamics
- Plant Water Relations and Carbon Dynamics
- Water Quality and Resources Studies
- Peatlands and Wetlands Ecology
- Geochemistry and Geologic Mapping
- Geological and Tectonic Studies in Latin America
- Insect and Arachnid Ecology and Behavior
- Climate change and permafrost
- Rangeland and Wildlife Management
- Image Processing and 3D Reconstruction
- Reservoir Engineering and Simulation Methods
Texas Tech University
2022-2025
University of California, Riverside
2006-2022
University of Kansas
2009-2018
University of Illinois Urbana-Champaign
2016
Universidade de São Paulo
2016
Abstract. Hydro-pedotransfer functions (PTFs) relate easy-to-measure and readily available soil information to hydraulic properties (SHPs) for applications in a wide range of process-based empirical models, thereby enabling the assessment effects on hydrological, biogeochemical, ecological processes. At least more than 4 decades research have been invested derive such relationships. However, while methods, data storage capacity, computational efficiency advanced, there are fundamental...
Abstract Rooting depth is an ecosystem trait that determines the extent of soil development and carbon (C) water cycling. Recent hypotheses propose human‐induced changes to Earth's biogeochemical cycles propagate deeply into subsurface due rooting from agricultural climate‐induced land cover changes. Yet, lack a global‐scale quantification responses human activity limits knowledge hydrosphere‐atmosphere‐lithosphere feedbacks in Anthropocene. Here we use data sets demonstrate root...
Abstract Soil biota generates carbon that exports vertically to the atmosphere (CO 2 ) and transports laterally streams rivers (dissolved organic inorganic carbon, DOC DIC). These processes, together with chemical weathering, vary flow paths across hydrological regimes; yet an integrated understanding of these interactive processes is still lacking. Here we ask: How what extent do subsurface transformation, solute export differ structure regimes? We address this question using a hillslope...
The depth distribution of soil organic carbon (SOC) is governed by the interaction many ecosystem features, including differential C inputs in shallow and deep soils redistribution via water flow through profile. In C-rich Mollisols particular, we need to better understand degree which conversion native prairie cultivated lands changing loss retention. We probed multiple mechanisms driving these processes using two approaches: one leverages a regional-scale dataset derived from Natural...
This study examined the application of a relatively new automated three‐dimensional scanning technology to bulk density determination intact soil clods and rock fragments. The method uses an inexpensive commercially available desktop scanner. Measurements obtained by were compared with those paraffin‐coated clod determined on same clods. Results showed excellent agreement between volume measurements two methods across wide range textural classes. Use has several important advantages over...
Roots and associated microbes generate acid-forming CO2 organic acids accelerate mineral weathering deep within Earth’s critical zone (CZ). At the Calhoun CZ Observatory in USA’s Southern Piedmont, we tested hypothesis that deforestation-induced root losses reduce root- microbially-mediated agents well below maximum density (to 5 m), impart land-use legacies even after ~70 y of forest regeneration. In forested plots, declined with depth to 200 cm; cultivated roots approached zero at depths...
Soil hydraulic properties influence the partitioning of rainfall into infiltration versus runoff, determine plant-available water, and constrain evapotranspiration. Although rapid changes in soil from direct human disturbance are well documented, climate change may also induce such shifts on decadal time scales. Using soils a 25-year precipitation manipulation experiment, we found that 35% increase water inputs substantially reduced rates modestly increased retention. We posit these were...
Research Article| March 01, 2008 Large near-surface nitrate pools in soils capped by desert pavement the Mojave Desert, California Robert C. Graham; Graham 1Soil & Water Sciences Program, Department of Environmental Sciences, University California–Riverside, Riverside, 92521-0424, USA Search for other works this author on: GSW Google Scholar Daniel R. Hirmas; Hirmas Yvonne A. Wood; Wood 2University Cooperative Extension, Inyo-Mono Counties, 207 West South Street, Bishop, 93514, Christopher...
Abstract. Land surface models (LSMs) are critical components of Earth system (ESMs), enabling simulations energy and water fluxes essential for understanding climate systems. Soil hydraulic parameters, derived using pedotransfer functions (PTFs), key to modeling soil-plant-water interactions but introduce uncertainties in soil moisture predictions. However, a knowledge gap exists how specific properties contribute these identifying the regions most affected by them. This study assesses...
Abstract Identifying and quantifying preferential flow (PF) through soil—the rapid movement of water spatially distinct pathways in the subsurface—is vital to understanding how hydrologic cycle responds climate, land cover, anthropogenic changes. In recent decades, methods have been developed that use measured soil moisture time series identify PF. Because they allow for continuous monitoring are relatively easy implement, these become an important tool recognizing when, where, under what...
Mountains are impressive features of many desert landscapes because their elevation, complex topography, and sheer extent. Soil genesis landscape processes were studied in the southern Fry Mountains, Mojave Desert, California. Our aim was to better understand responsible for distribution soil properties this landscape. Measured 65 pits across study site show that dust, soluble salt, NO 3 − –N, carbonate distributions correlated with prevailing wind direction. This finding suggests mountain...
Abstract The purpose of this paper is to test the application a new, low-cost ($2995.00 US), multistripe laser triangulation (MLT) scanner and three-dimensional (3D) software for semiquantitative quantitative analyses ichnofossils modern traces. goal research improve on existing analytical techniques apply new methods 3D digital models Objectives are (1) provide researchers with ways develop hypotheses quantitatively in fields paleoichnology, neoichnology, sedimentology, soil science, (2)...
Abstract. Soil organic carbon (SOC) is often retained more effectively in aspen-dominated forests compared to coniferous North America, yet the reasons why are unclear. A potential driver could be differences SOC protection mechanisms. Over decades centuries, chemical (e.g., mineral association) and physical aggregation) processes can work preserve stocks, which vary across cover types. To investigate this hypothesis, we evaluate controls on concentrations Coal Creek watershed (CO, USA), a...