In Oregon perennial and annual grass seed cropping systems conservation management practices and their impacts on soil health and soil microbial community is not well understood. There is strong motivation to employ conservation tillage and other conservation practices to curb atmospheric carbon levels and improve soil health. However, the few...
In the Columbia Basin, pre-plant soil fumigation is commonly used in potato production for pest control, but fumigation can kill non-target organisms within the soil, result in unintended shifts in the microbial community, and disrupt long-term soil health. Cover crops have been shown to strongly influence the numbers and communities...
“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...
Deeply weathered soils in tropical rainforests and savannas are classified as Ferralsols according to the World References Bases for Soil Resources (WRB). Ferralsols are most nearly akin to the Oxisols order defined in the US Soil Taxonomy. The acidity, low cation exchange capacity, and strong phosphorus retention by the oxidic...
Arctic warming is exposing thawing permafrost to repeated freeze-thaw, a disruptive process that can alter soil biogeochemistry and physical structure. To investigate the impact of permafrost exposure to freeze-thaw, soil response was tested across three scales: 2.5 cm³ aggregates, a forested hillslope, and two sites at contrasting latitudes. XCT imaging...
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...
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,...
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...
Amendments and fertilizers applied to optimize crop production and improve soil health also supply inputs of soil organic matter (SOM) and nutrients that affect soil microorganisms. In the dairy-intensive Pacific Northwest, dairy manure is stored as slurry mixtures until conditions are appropriate for soil application. During storage, the manure begins...