Vertisols and other vertic-intergrade soils are found all over the globe, including many agricultural and urban areas. These soils are characterized by their cyclical shrinking and swelling behaviors, where bulk density and porosity distribution both vary as functions of time and/or soil moisture. In turn, alterations in physical soil parameters...
The perhumid coastal temperate rainforests of southeast Alaska contain an abundance of soil organic carbon (SOC) that has accumulated in a wet, cool climate where forest fire disturbance is minimal and organic matter decomposition rates are low. Coastal temperate rainforests are supported by carbon-rich soils that provide ecosystem services including...
Various soil tests are routinely used in the United States to predict soil lime requirement. New non-hazardous methods have recently been proposed for adoption in Oregon, however the accuracy of these methods for Oregon soils has not been established. The objectives of this investigation were: (a) to document and describe...
The effects of fire on above-ground forest systems have been extensively studied. However, research on fire effects on belowground processes is lacking. While the soil microbiome is understood to be vital to conifer growth and regeneration, the complexity of soils means that research on the topic has largely been accomplished...
Onion thrips (Thrips tabaci) are pests found in onion fields of the Treasure Valley, which is located in Eastern Oregon and Western Idaho. Thrips cause damage to this high value crop by feeding on the onion’s extracellular fluid, making photosynthesis more difficult to occur. The feeding from the thrips can...
Remote sensing techniques have been applied extensively in geospatial investigations, but their use in measuring soil physical attributes has been far less explored. Soil particle size distributions (PSD) are indispensable in modeling pedological and hydrological processes as well as biodiversity. However, estimation of PSD via gravimetric measurement methods, the standard...
Temperate coniferous forests, such as those that cover vast areas of the western US and Canada, have evolved to depend on cycles of disturbance for succession of species and overall ecosystem maintenance. Many of these forest systems are managed, often for timber production, where disturbances are of anthropogenic origin and...
The Pacific Northwest region of the United States is known for quality production of blueberries, blackberries, and red raspberries. However, as the climate shifts to warmer, drier, and more extreme summers, growing these water intensive berry crops is becoming increasingly difficult. Furthermore, water regulations within agriculture are becoming more prevalent...
“Active carbon” is a rapidly cycling soil organic carbon (SOC) fraction that acts as an energy and nutrient source for the microbial community. Dilute permanganate oxidation has been used to measure an “active carbon” fraction with the assumption that permanganate oxidation mimics enzymatic decomposition. Permanganate oxidizable carbon (PoxC) has become...
Coastal Temperate Rainforests of western North America are carbon dense ecological regions of great importance due to their high biological productivity and climatic conditions leading to the natural accumulation of soil organic carbon (SOC). Yet, the distribution of SOC remains understudied in the CTR environments, particularly in upland mineral soils,...