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Study of the catalytic reactions of ethylene oligomerization in subcritical and supercritical media over a NiBEA catalyst
We report a study of the catalytic reactions of ethylene oligomerization over nickel impregnated in aluminum silicate using subcritical and supercritical media. We found the BET surface area decreases with increasing nickel loading, indicating the deposition of NiO particles in the catalyst surface. We compared the performance ...
The Effects of Different Harvest Intensities on the Distribution of Soil Phosphorus and Nutrient Stocks in a Brazilian Oxisol
Forest soils form an important reservoir in ecosystem nutrient and carbon budgets, which are crucial for sustained productivity of forests. Nutrient fluxes and transformations in forest soils are a result of a complex interchange between the atmosphere, plants, and soil. Consequently, soils are a critical source of plant ...
Fire, Charcoal, and the Biogeochemistry of Carbon and Nitrogen in Pacific Northwest Forest Soils
The rain shadow forests of the Olympic peninsula represent a unique, mixed-severity fire regime class in the midst of a highly productive landscape where spatial heterogeneity of fire severity may have significant implications for below and aboveground post-fire recovery. The purpose of this study was to quantify the impacts ...
Bioretention Soil Media: Understanding the effects of compost and finding predictors for phosphorus leaching
This study is intended to 1) investigate the effect of compost rate and compost type on bioretention soil media (BSM) performance, and 2) explore possible predictors of phosphorus leaching from bioretention systems. Columns with 14 different bioretention soil media (BSMs) were analyzed in a greenhouse over the course of 60 ...
Land-Use Changes in Southwestern Guatemala: Assessment of their Effects and Sustainability
(2013-07-23)
Land-use changes in the Pacific coastal plain of southwest Guatemala have accelerated in the past twenty years as native arable and pasture lands have been converted at an increasing rate to oil palm and banana plantations. This study of the changes during this period has been made by remote-sensing analyses calibrated to ...
An Examination of Stand Attributes and the Presence of English holly in a Pacific Northwest Forest, Grays Harbor County, Wash.
(2013-07-23)
English holly (<italic>Ilex aquifolium</italic>) is an ornamental favored by people who appreciate its wildlife benefits and traditional significance. Since its introduction into the Pacific Northwest over one hundred years ago, (<italic>Ilex(</italic> has escaped from cultivation and is increasingly found in natural areas ...
Conservation of freshwater thermal habitats for Pacific salmon in a changing climate
Climate adaptation strategies for freshwater biota have focused on how water temperature and hydrology will change over time, but understanding spatial patterns in water temperature will also be essential for evaluating vulnerability of biota to future climate and for identifying and protecting diverse thermal habitats. I ...
Locally produced wood biochar increases nutrient retention in agricultural soils of the San Juan Islands, WA, USA
Biochar additions to agricultural soil have been shown to result in many benefits; however, most studies have been conducted in greenhouse or laboratory trials with few being conducted in the field and particularly in association with organic farming systems. Herein, this gap was addressed by conducting on-farm studies on ...
Soil Influence on Forest Vegetation Productivity and Patterns in the Eastern Cascades of Southern Oregon
Soils influence vegetation and can critically affect forest restoration results. Areas with similar parent materials can have changes in soil and vegetation across a slope, aspect, slope position, microtopography, and elevation. The objective of this project was to assess what soil characteristics influence vegetation ...
Stem and Branch Diameter Response in Pruned Douglas-fir Plantations (Pseudotsuga menziesii var. menziesii): Implications for Volume and Clear Wood Production in the U.S. Pacific Northwest
Enhancement of timber quality from self-pruning in Douglas-fir stands typically begins to occur around 60-80 years of age. Due to 40-year rotations in production settings, this species has the potential to benefit from the silvicultural treatment of pruning. Previous literature indicates that pruning may increase overall ...