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Viticulture & Enology Technical Newsletter : Spring 202
Get PDFThis edition contains research updates and a comprehensive list of publications summarizing research conducted by faculty of the Oregon Wine Research Institute at Oregon State University. Drs. Alexander Levin and Achala KC, both assistant professors at OSU-Southern Oregon Research and Extension Center (SOREC), along with Cody Copp, graduate research assistant, open the newsletter with an article on grapevine red blotch disease. Dr. Laurent Deluc, OSU associate professor, reports on research studying grape seed and berry development. Dr. R. Paul Schreiner, USDA-ARS research plant physiologist, and Tian Tian, OSU graduate research assistant, provides information on measuring leaf water potential. Lastly, Drs. Jay Pscheidt, Robin Rosetta, and Lloyd Nackley, and Brent Warneke, faculty research assistant, give an update on the Intelligent Sprayer System. We wrap up the newsletter with a list of new publications authored by Oregon Wine Research Institute researchers
Viticulture & Enology Technical Newsletter : July 2011
No full textThis newsletter comes at the advent of bloom and fruit set in this 2011 season. To provide information on timely topics, Patty Skinkis provides an article on early season leaf removal and how it may help reduce disease infection. Inga Zasada provides information on plant parasitic nematodes to help you prepare for vineyard nematode sampling if this is a concern. On the enology side, James Osborne provides a summary on protein fining of white wine. Be sure to check out the new publications and online resources section, as we have some fantastic new resources for you to consider using in the vineyard. Finally, we have some upcoming events through OSU and OWRI that will help keep you informed, so be sure to mark your calendars
Evaluation of various chemical treatments to prevent the abiotic deterioration of southern pine surfaces through outdoor screening trials
Get PDFRapid discoloration and checking of wooden surfaces when exposed outdoors has caused wood to fall out of favor as an outdoor building material, especially in applications where appearance is important. The surface appearance of wood products exposed outdoors can be improved through the application of film forming coatings or by reducing exposure to solar radiation and moisture. A shift towards environmentally friendly building materials has renewed interest in the outdoor application of wood products, where both biotic and abiotic durability is required, often in the absence of large overhangs or maintenance-intensive film forming coatings. The deterioration processes of wood surfaces have been extensively investigated. It is generally accepted that the loss of lignin and hemicellulose from the surface due to free radical reactions initiated by UV light absorption and moisture leads to discoloration and erosion. In addition, it is thought that these chemical reactions also weaken the wood surface, resulting in checking. Further, a large body of research has been assembled investigating different treatments, primarily film forming, that prevent the effects of weathering. Yet, only chromic acid treatments have emerged as an economical means for reducing the effects of outdoor exposure without obscuring the natural figure of the wood. However, due to the toxic nature of these compounds, these treatments have never been commercialized.
In this body of work, two outdoor screening weathering studies were conducted to investigate the interactions between the wood surface and four classes of promising surface protection compounds. Representative water repellents, pigments, organic UV inhibitors, and carbon based wood preservatives were selected for the initial study. Samples were pressure impregnated with the candidate systems and subjected to exterior exposure at two sites. Exposure sites were located in the high desert of Oregon and on the leeward side of the island of Hawaii. These locations represent the extremes experienced by most wood based building materials. The Oregon site has low rainfall but high UV exposure while the Hawaiian site has both high rainfall and high UV. Samples were removed from the Oregon site at predetermined radiation intervals over a one year period, while the samples exposed in Hawaii were removed after six months of weathering. Following exposure, the samples were evaluated for discoloration, checking and changes in the chemical composition of the surface. The results from this study indicated that none of the selected treatments completely prevented the effects of weathering on the wood surface; yet some fared better than others in at least some of the categories analyzed. The study also indicated that the mode of deterioration differed significantly between the two exposure locations and that chemical degradation of the surface did not necessarily correlate with checking or discoloration.
Red and yellow iron oxide impregnated loblolly pine (Pinus taeda) samples experienced less discoloration and reduced lignin loss during the first study at both exposure locations, suggesting that iron oxides may alter the interaction between UV light and the wood polymers. In a follow up, study loblolly pine samples were impregnated with iron oxide pigments differing in particle size, shape and loading to determine what characteristics of iron oxide influenced surface protection properties. These samples were only exposed at the eastern Oregon location and removed over a three month period at predetermined radiation intervals. The results from this work suggest that crystal shape, size and pigment concentration influenced polymer losses from the wood surface as well as surface discoloration. However, the results suggested that checking was not affected by any of the variables investigated.
While these studies suggest that the abiotic deterioration of wood surfaces can be controlled through the application of different transparent and semitransparent treatments, no single compound was completely effective. This implies that combinations of partially effective compounds should be investigated. In addition, the data suggest that, lignin and hemicellulose loss do not substantially affect check formation during the first months of outdoor exposure. Instead, the data suggests that wood / water relations dominate. The different exposure locations used in the first study also highlighted differences in weathering characteristics caused by climate. More research must be conducted to understand the effects of different climates on performance and to use these data to tailor surface protection systems to match exposure conditions.Keywords: Checking and discoloration, Water repellents, Iron oxide pigments, Hawaii, Eastern Oregon, Wood surfaces, Surface protection, Climate, Weathering, Fourier transform infrared spectroscopy (FTIR
The Effects of Host and Pathogen Variation on Infection Dynamics in the Amphibian-Chytrid System
Get PDFThis dissertation uses manipulative experiments to explore amphibian-Bd infection dynamics. Although there has been almost two decades research since the discovery of Bd, many questions still remain regarding what conditions mediate chytridiomycosis virulence. My research shows how certain host and pathogen factors can influence disease virulence. Identifying how host and pathogen factors mediate disease virulence is important in order to understand, predict, and mitigate this infectious amphibian disease. Worldwide biodiversity loss is occurring at unprecedented rates. Numerous factors are contributing to this loss, including infectious disease. Among vertebrate groups, amphibians are experiencing the highest rate of population declines and extinctions and are vulnerable to numerous infectious pathogens that appear to be contributing to amphibian biodiversity loss. A widespread infectious chytrid fungus, Batrachochytrium dendrobatidis (Bd), causing the disease, chytridiomycosis, is implicated in numerous amphibian population declines and extinctions and can induce sublethal effects within individuals. My dissertation research examines host-pathogen factors that mediate infection outcomes in the amphibian-Bd system. The severity of an infectious disease is the result of specific host-pathogen interactions. Thus, there may be large variation in disease outcome depending on host and pathogen related factors. In Chapter 2, I conducted a comparative experimental study in larval amphibians using multiple host species and Bd strains. I showed that host species varied in Bd susceptibility but that susceptibility was also contingent on Bd strain type. Thus, I showed chytridiomycosis virulence depended upon host and pathogen traits and that a sensitive host species could be robust to certain pathogen strains. In Chapter 3, I experimentally investigated multiple pathogen interactions with amphibian three amphibian host species to examine how Bd infection dynamics might change under simultaneous coinfection with a common water mold, Saprolegnia ferax (Sf). Coinfecting pathogens might interact within a host in a synergistic and antagonistic manner. In two host species, Bd infection intensity was slightly higher in hosts that were exposed to both Bd and Sf compared to just Bd alone indicating a small synergistic interaction with Sf. However, the differences were not significant in either host species. Survival differences were only detected in one host species; hosts exposed to Bd only experienced lower survival than those in the coinfected group. Additionally, I found host weight and days survived were predictive of Bd infection level for some hosts species showing species variation in infection response. Lastly, in Chapter 4, I experimentally examined age-dependent differences in Bd infection heterogeneity in two host species. I followed this with another experiment to test whether age-dependent differences in infection intensity of these hosts (‘donors’) influenced subsequent Bd transmission to a naïve conspecific host (‘recipients’). I found Bd infection intensity differences among juvenile and adult donors of both species. However, trend directions were not consistent; in one host species, adults had significantly higher infection levels than juveniles while the opposite was true in the second host species. Regardless of donor infection intensity, recipients had comparable infection levels within each host species. Survival also differed among host species and age groups suggesting Bd susceptibility may change with age and is species specific.Keywords: chytridiomycosis, amphibian population decline, Batrachochytrium dendrobatidis, infectious diseas
Teaching fundamental computer science concepts utilizing manipulatives
Get PDFThis thesis presents innovative pedagogical approaches to teach fundamental Computer Science (CS) concepts, such as abstraction, representation, algorithms, and computation utilizing manipulatives, which are physical objects that students interact with to teach or reinforce a concept. Teaching and learning with manipulatives has a long history in science and mathematics education, but the development of and research on manipulatives to teach CS concepts is less common. Through observational field notes from a 6th-grade classroom and an interview with the teacher, this thesis discusses the affordances and drawbacks of the different approaches and manipulatives.
We found that utilizing manipulatives led to increased student engagement and participation with the material, along with making teaching the material more exciting and engaging for the teacher. In addition, we found that manipulatives provided a way for student misunderstandings and errors to be more apparent through tinkering with the physical objects, along with the teacher being able to connect and further enforce multiple CS concepts through activities. However, we also observed drawbacks when implementing different manipulatives, specifically the algorithmic scaffolding restricted the ability for an algorithm to be created and designed in unique a way by a student, which could lead to less algorithmic creativity and freedom.Keywords: Computer Science, Manipulatives, Abstraction, Algorithms, Representation,
Computation, Computer Science Educatio
Integrating solute transport, metabolism and processing in stream ecosystems
Get PDFAfter three decades of active research coupling hydrology and stream ecology, the connection among solute transport, metabolism and processing is still unresolved. These knowledge gaps obscure the functioning of stream ecosystems and how those ecosystems interact with other landscape processes. We must resolve these challenges to wisely manage water resources, because there is a need to understand controls on stream ecosystems at local, regional and continental scales, and because we need to predict in-stream biogeochemical processes in environments and conditions that do not have supporting data. More robust methods are required to deconvolve signal imprints of solute transport, metabolism and processing, thus allowing the development and implementation of improved decision-making approaches for stream management. Recognizing that uncertainty and equifinality are ubiquitous issues in hydrologic problems, this dissertation focuses on the development of parsimonious methods to couple solute transport, metabolism and processing in stream ecosystems. These methods consist of scaling and predicting relationships for solute transport, efficient modeling frameworks to estimate processing rates in streams, and the use of the smart tracer resazurin to estimate stream metabolism at different spatial scales. This dissertation is the result of lab and field experiments, meta-analyses, and mathematical, statistical and computational modeling. The most significant contributions of this dissertation to the hydrological and biogeosciences are: (1) there are scaling relationships in stream solute transport. We found that the coefficient of skewness (CSK) of conservative tracer breakthrough curves is statistically constant over time and this result can be used to predict solute transport. (2) The CSK of all commonly used solute transport models decreases over time. This shows that current theory is inconsistent with experimental data and suggests that a revised theory of solute transport is needed. (3) Simple algebraic relationships can be used to estimate processing rates in streams. This eliminates the need to calibrate highly uncertain (and intermediate) parameters. (4) Under some common stream transport conditions dispersion does not play an important role in the estimation of processing rates and, therefore, can be neglected. Under such conditions, no computer modeling is needed to estimate processing rates. (5) Even if the reactions of target and proxy tracers happen in exactly the same locations at rates that are linearly proportional, the exact relationship between the two volume-averaged rates can be nonlinear and a function of transport conditions. However, the uncertainty in the estimation of the target processing rate is linearly proportional to the proxy-tracer processing rate. (6) The transformation of resazurin is nearly perfectly, positively correlated with aerobic microbial respiration. Therefore, resazurin can be used as a surrogate to measure respiration in situ and in vivo at different spatial scales (this is an extension of (5)). (7) Community respiration rates in streams may not need to be "corrected" for temperature between daytime and nighttime, because even when photosynthetically active radiation and stream water temperature are different, respiration rates might not be different across nighttime and daytime conditions.Keywords: metabolism, tracers, transport, streams, transient storage, processin
Carbon dynamics in response to land cover change in tropical peatlands, Kalimantan, Indonesia
Get PDFThis study focuses in providing the knowledge on carbon (C) stocks, emission and ecosystem productivity related to land use/land cover change in tropical peatlands. The field research activities were conducted for about 17 months between August 2013 to December 2015, at Pematang Gadung peat dome (peat depth up to 10.5 m), Ketapang Regency, West Kalimantan, Indonesia. The objectives of this study were: a). to quantify C stocks of tropical coastal peat swamp forest, and the potential impact of forest degradation due to draining and logging activities on the forest’s carbon stocks; b). to examine the change in ecosystem C stocks and the potential C emissions in relation to land conversion from intact peat swamp forest (PSF) to logged peat forest (LPSF), early seral (ES) and oil palm plantation (OP); and c). to estimate net primary production (NPP) and net ecosystem production (NEP) in peat swamp forests, logged peat forest, early seral and smallholder - oil palm plantations.
The intact peat forest sites have higher total aboveground C stocks (125 Mg C ha-1) than the logged peat forest sites (77 Mg C ha-1). Mean depths of the LPSF was 725 cm and the PSF was 915 cm (p= 0.06). Mean peat carbon stocks at PSF was 4,243 Mg C ha-1, higher than at LPSF that was 3,675 Mg C ha-1. Logging and draining had reduced the biomass of trees and the peat carbon pools. My study demonstrated that tropical coastal PSF has the largest total carbon stocks among terrestrial ecosystems on earth. The large carbon stocks and high rates of PSF degradation, points to the relevance for inclusion of PSF in nationally appropriate climate change mitigation and adaptation strategies.
The mean ecosystem carbon stock for the PSF sites was 4,401 Mg C ha-1. Ecosystem C stocks of LPSF, ES and OP was 3,768, 3,147, and 3,442 Mg C ha-1, respectively. PSF stocks was significantly higher than the degraded land covers. At all sites, soils comprised > 96% of the mean ecosystem carbon stock. Using the estimation based on ecosystem carbon loss to total peat depths, the conversion of PSF to LPSF, ES and OP was estimated to result in a net loss of 1,982, 4,259 and 3,176 Mg C-CO2 ha-1, respectively. My results confirm that land cover change significantly impacted soil properties and reduced ecosystem carbon stocks. The tropical peatlands need urgent and significant efforts in conservation and restoration, to regain its function as a C sink and mitigate climate change.
I found that land use/land cover change resulted in large shifts in NPP and NEP. LPSF, ES and OP have significantly lower NPP (11.1 Mg C ha-1 yr-1, 10.8 Mg C ha-1 yr-1 and 3.7 Mg C ha-1 yr-1, respectively) than PSF (13.2 Mg C ha-1 yr-1). ES showed lower heterotrophic respiration (30.7 Mg CO2 ha-1 yr-1) than PSF, LPSF and OP (37.7 Mg CO2 ha-1 yr-1, 40.7 Mg CO2 ha-1 yr-1, 38.7 Mg CO2 ha-1 yr-1, respectively). LPSF and OP were net carbon sources; they have negative mean NEP values (-0.1 Mg CO2-e ha-1 yr-1 and -25.1 Mg CO2-e ha-1 yr-1, respectively). In contrast PSF and ES were net carbon sinks (10.8 Mg CO2-e ha-1 yr-1 and 9.1 CCO2 ha-1 yr-1, respectively). PSF is among the most productive of terrestrial ecosystems, with an NPP exceeding that of many tropical rain forests and similar to the most productive mangrove ecosystems. I found that land use decreases productivity of the LPSF and OP sites. The ES had a similar NEP to the PSF, but frequent fires in this ecosystem likely offset carbon gains during the fire intervals.
Land use change and forest degradation have shifted tropical PSFs from net carbon sinks to net carbon sources. My study demonstrated that land conversion in tropical peat swamp forests should be halted and degraded peatlands need to be restored in order to mitigate climate change.Keywords: Oil palm plantation, Drainage, NPP, Logging, NEP, CO2 fluxes, Land use changes, Peat swamp forests, Emission Factor, Carbon stock
A Review of Water Banking in State Legislation of the Western United States
Get PDFAmong the suite of water resources management strategies, water banking can be a tool for water resource management in areas with high water demands or localized water scarcity. This research aims to further the understanding of water banking by conducting a review and analysis of relevant state legislation. This research identified legislation that explicitly mentions water banking and then assessed how states compare on the comprehensiveness of their water banking legislation.In this study over three hundred pieces of legislative documents referencing water banks and water banking were examined and coded to compare the nineteen states that use the Prior Appropriation Doctrine. Of the states examined, seven states had no mention of water banking in their legislation. The remaining twelve states were assessed and compared on a qualitative scale of comprehensiveness through twenty-eight categories. Washington, Arizona, and New Mexico rank consistently high in the individual categories, such as quantity and management, and the overall analysis determined that the state of Washington has the most comprehensive legislation regarding water banking. Conducting this research has enabled the identification of policy elements and objectives most often associated with water banking and has provided a platform for further discussions on how the progression of water banking legislation can compare to the growth of water banking practices and other water resource management strategies.Keywords: water bank, water banking, Prior Appropriation Doctrine, state legislation, water resources policy and managemen
Examination of Photochemical Water Treatment by SolarBags
Get PDFInadequate access to clean water is an ongoing problem in many developing areas of the world. In developed nations, it is important to plan for access to clean water following natural disasters. In situations without reliable access to electricity and chemical treatment methods, there is a need for an inexpensive water treatment solution that can be used in a wide range of environmental conditions. The Puralytics SolarBag aims to meet these needs by providing a product that can purify water through the use of solar activated nanotechnology. The SolarBag contains a titanium dioxide nanoparticle laced mesh that reacts under sunlight to help inactivate potential microbial contaminants. This work aims to evaluate the effectiveness of the SolarBag and a new prototype, the SolarBag Plus, to treat 3L of surface water in 3 hours of exposure to sunlight. Tests were conducted using two synthetic test waters, a general test water and a challenge test water, which contained higher levels of salts, humic acids, and higher turbidity. To evaluate inactivation of microbial contaminants, synthetic test waters included representative bacteria (Escherichia coli), viruses (bacteriophages MS2 and ΦΧ174) and protozoa (Cryptosporidium parvum). This work additionally aimed to characterize the contributions of various photochemical and thermal processes to the overall treatment of the water. The results from this study indicate that E. coli is primarily inactivated by UV photoinactivation and suggest that inactivation is greatly increased at temperatures above 45˚C. Bacteriophage MS2 appears resistant to treatment by solar irradiation, but shows consistent removal under different environmental conditions. It is hypothesized that this removal is the result of the synergistic treatment by heat and light or a physical removal process like adsorption. Bacteriophage ΦΧ174 is inactivated by a combination of UV light and heat. Finally, C. parvum removal was generally low in the SolarBag under all conditions. Physical removal by filtration contributed to the greatest removal of oocysts in the treatment process, though improvement in inactivation was noted with higher UV intensity. The addition of ClO2 to the water treatment process removed all detectable microorganisms within 2 hours. Some data suggests that the use of ClO2 enhances the activity TiO2, but it was determined that chemical disinfection was the predominant mechanisms of disinfection when present
PTIE : reflections on university strategic planning & holistic faculty evaluation
Get PDFBased on long-standing involvement and experience with promotion and tenure at the university level, in this paper, we examine the importance of university strategic planning and holistic faculty evaluation in realization and implementation of the promotion and tenure - innovation and entrepreneurship (PTIE) recommendations. After developing a reflection protocol, we engaged with self-introspection on efforts within the past decade at our university and the resulting progress with PTIE on our campus. Our reflections suggest that proper consideration of innovation and entrepreneurship (I&E) activities as part of the promotion and tenure review process are constrained in the absence of a holistic faculty review. Similarly, a university-wide commitment to I&E, as reflected within the university strategic plan, must be followed by a concrete implementation action plan. To this end, and based on lived experiences, we present a few practical suggestions and recommendations for higher education institutions