Accelerated release of carbon from soils is one
of the most important feedbacks related to anthropogenically
induced climate change. Studies addressing the mechanisms
for soil carbon release through organic matter decomposition
have focused on the effect of changes in the average temperature,
with little attention to changes in temperature variability....
Each year, whether it be under voluntary or unvoluntary circumstances, countless professional athletes retire from their sport. Even by the average retirement age of 30, many are still underprepared to face the challenges that accompany the transition. Along with the changes in schedule, identity, and social group, numerous professional athletes...
Soil organic matter is a complex mixture of material with heterogeneous biological, physical, and chemical properties. Decomposition models represent this heterogeneity either as a set of discrete pools with different residence times or as a continuum of qualities. It is unclear though, whether these two different approaches yield comparable predictions...
In the Pacific Northwestern United States, the hop powdery mildew fungus, Podosphaera macularis, survives overwintering periods in association with living host tissue because the ascigerious stage of the pathogen is not known to occur in this region. Field experiments were conducted over a 5-year period to describe the overwintering process...
Optimum timing and use of fungicides for disease control are improved by an understanding of the characteristics of fungicide physical mode of action. Greenhouse and field experiments were conducted to quantify and model the duration of pre- and postinfection activity of fungicides most commonly used for control of hop downy...
Optimum timing and use of fungicides for disease control are improved by an understanding of the characteristics of fungicide physical mode of action. Greenhouse and field experiments were conducted to quantify and model the duration of pre- and postinfection activity of fungicides most commonly used for control of hop downy...
Full Text:
(B), and in a field experiment during 2013
(C), in relation to timing of fungicide applications and
Optimum timing and use of fungicides for disease control are improved by an understanding of the characteristics of fungicide physical mode of action. Greenhouse and field experiments were conducted to quantify and model the duration of pre- and postinfection activity of fungicides most commonly used for control of hop downy...
Optimum timing and use of fungicides for disease control are improved by an understanding of the characteristics of fungicide physical mode of action. Greenhouse and field experiments were conducted to quantify and model the duration of pre- and postinfection activity of fungicides most commonly used for control of hop downy...
Full Text:
97331; and Megan C. Twomey, Sierra N. Wolfenbarger, and
Joanna L. Woods, Department of Botany and Plant
Optimum timing and use of fungicides for disease control are improved by an understanding of the characteristics of fungicide physical mode of action. Greenhouse and field experiments were conducted to quantify and model the duration of pre- and postinfection activity of fungicides most commonly used for control of hop downy...
Knowledge of processes leading to crop damage is central to devising rational approaches to disease management. Multiple experiments established that infection of hop cones by Podosphaera macularis was most severe if inoculation occurred within 15 to 21 days after bloom. This period of infection was associated with the most pronounced...
The management of federal forest lands in the Pacific Northwest (PNW) region changed in early 1990s when the
Northwest Forest Plan (NWFP) was adopted with the primary goal to protect old-growth forest and associated
species. A major decline in timber harvest followed, extending an earlier downward trend. The historic and...
Host resistance, both quantitative and qualitative, is the preferred long-term approach for disease management in many pathosystems, including powdery mildew of hop (Podosphaera macularis). In 2012, an epidemic of powdery mildew occurred in Washington and Idaho on previously resistant cultivars whose resistance was putatively based on the gene designated R6....
Host resistance, both quantitative and qualitative, is the preferred long-term approach for disease management in many pathosystems, including powdery mildew of hop (Podosphaera macularis). In 2012, an epidemic of powdery mildew occurred in Washington and Idaho on previously resistant cultivars whose resistance was putatively based on the gene designated R6....
Full Text:
sulfur nightly for 2 h. The green-
house was maintained at 20 to 25°C with a 14-h photoperiod. Plants
Host resistance, both quantitative and qualitative, is the preferred long-term approach for disease management in many pathosystems, including powdery mildew of hop (Podosphaera macularis). In 2012, an epidemic of powdery mildew occurred in Washington and Idaho on previously resistant cultivars whose resistance was putatively based on the gene designated R6....
The experiment described in this paper was designed and carried out to study the ability of five provenances of white spruce of acid soil origin and five provenances of basic soil origin grown on an did and a basic soil to utilize and respond to the five macro-nutrient elements N,...
The size of the bioavailable (i.e., “fixed”) nitrogen inventory in the ocean influences global marine productivity and the biological carbon pump. Despite its importance, the pre-industrial rates for the major source and sink terms of the oceanic fixed nitrogen budget, N₂ fixation and denitrification, respectively, are not well known. These...
In this paper we consider models of two competing species that are both affected by a pathogen which is transmitted directly. We consider both mass action as well as frequency incidence models of disease spread, and Lotka-Volterra competition. Our aim is to address the interaction between competition and disease dynamics....
Atmospheric surface layer turbulent statistics measured during the Barbados Oceanographic and Meteorological Experiment 8 and 30 m above mean sea level are presented. The budget equations of turbulent kinetic energy, humility variance and temperature variance are examined. Within discussed limitations it is concluded that production equals dissipation in the case...
A three-dimensional, process-based model of the ocean’s carbon and nitrogen cycles, including
13C and 15N isotopes, is used to explore effects of idealized changes in the soft-tissue biological pump. Results
are presented from one preindustrial control run (piCtrl) and six simulations of the Last Glacial Maximum
(LGM) with increasing values...
Full Text:
(13C / C ) / (13C / C )std 1 is the ratio of 13C over C
normalized to that of a standard and the
A three-dimensional, process-based model of the ocean’s carbon and nitrogen cycles, including
13C and 15N isotopes, is used to explore effects of idealized changes in the soft-tissue biological pump. Results
are presented from one preindustrial control run (piCtrl) and six simulations of the Last Glacial Maximum
(LGM) with increasing values...
Full Text:
Citation:
Schmittner, A., and C. J. Somes (2016),
Complementary constraints from
carbon (
13
C) and
The reason for the initial rise in atmospheric
CO₂ during the last deglaciation remains unknown. Most recent
hypotheses invoke Southern Hemisphere processes such
as shifts in midlatitude westerly winds. Coeval changes in
the Atlantic meridional overturning circulation (AMOC) are
poorly quantified, and their relation to the CO₂ increase is
not...
The reason for the initial rise in atmospheric
CO₂ during the last deglaciation remains unknown. Most recent
hypotheses invoke Southern Hemisphere processes such
as shifts in midlatitude westerly winds. Coeval changes in
the Atlantic meridional overturning circulation (AMOC) are
poorly quantified, and their relation to the CO₂ increase is
not...
Full Text:
overturning decline and its role in atmospheric
CO₂ rise inferred from carbon isotopes (δ¹³C)
Schmittner, A
A three-dimensional, process-based model of the ocean’s carbon and nitrogen cycles, including 13C and 15N isotopes, is used to explore effects of idealized changes in the soft-tissue biological pump. Results are presented from one preindustrial control run (piCtrl) and six simulations of the Last Glacial Maximum (LGM) with increasing values...
The reason for the initial rise in atmospheric
CO₂ during the last deglaciation remains unknown. Most recent
hypotheses invoke Southern Hemisphere processes such
as shifts in midlatitude westerly winds. Coeval changes in
the Atlantic meridional overturning circulation (AMOC) are
poorly quantified, and their relation to the CO₂ increase is
not...
During the Internal Waves on the Continental Margin (IWAVES) field experiments of 1996 and 1997 off of Mission Beach, California (32.75° N), we observed energetic, dirunal-band motions across the entire study site in water depths ranging from 15 to 500 m and spanning a cross-shore distance of 15 km. The...
We give a detailed description of the semidiurnal-band current and temperature
variability observed during the Internal Waves on the Continental Margin (IWAVES) field
experiments of 1996 and 1997 off of Mission Beach, California. This variability was
dominated by the internal tide, and the structure of the internal tide on the...
We present an optical method (optical current meter) to measure the longshore
component of nearshore surface currents by measuring the alongshore drift of persistent
sea foam in the surf zone. The method uses short time series of video data collected from
an alongshore array of pixels. These space-time data are...
We present an optical method (optical current meter) to measure the longshore
component of nearshore surface currents by measuring the alongshore drift of persistent
sea foam in the surf zone. The method uses short time series of video data collected from
an alongshore array of pixels. These space-time data are...
Monthly composite images from the global coastal zone color scanner
(CZCS) data set are used to provide an initial illustration and comparison of seasonal
and interannual variability of phytoplankton pigment concentration along the western
coasts of South and North America in the Peru Current system (PCS) and California
Current system...
Leaf nutrient concentration of hardy kiwifruit [Actinidia arguta var. arguta (Siebold and Zucc.) Planch. ex Miq.] was evaluated throughout two growing seasons (2008-2009) for determinate and indeterminate shoots of female ('Ananasnaya') and male vines. While research has been conducted on the more commonly grown fuzzy kiwifruit (A. chinensis var. deliciosa...