Research Report 1

RESEARCH REPORT 1. Name: Rose Z. Abramoff （ID No.: SP10001） 2. Current affiliation: Boston University 3. Research fields and specialties: Biological Sciences 4. Host institution: Tokyo City University 5. Host researcher: Dr. Hiromi Kobori 6. Description of your current research My current research focuses on the phenology of plants and animals with a specialization in temperate deciduous tree phenology. In Boston I have been tracking spring phenology for one year on an urban-to-rural gradient from Back Bay westward to Waltham. I am observing the following commonly found trees and shrubs: Weeping willow (Salix babylonica), Red maple (Acer Rubrum), Norway maple (Acer platanoides), Gray birch (Betula populifolia), Magnolias (Magnolia) Forsythia (Forsythia), Lilac (Syringia), Rhododendron (Rhododendron), and Sumac (Rhus). I hypothesize that the warmer city center will have earlier spring phenology as characterized by leaf out and first flowering date. I have placed temperature loggers at five locations along this transect in order to capture the temperature gradient. I plan to continue this project next year and to extend my transect to include the edge of the Charles River Watershed. I am currently pursuing a certificate in Terrestrial Biogeosciences in addition to my doctorate at Boston University. As part of our coursework, I and other graduate students are collaborating with Professor Adrien Finzi using metanalysis techniques to see how grain yield, nitrogen trace gas emissions, and runoff would change with a 50% reduction in nitrogenous fertilizers in four United States watersheds. When I return to Boston University in the fall, I hope to plan a precipitation manipulation experiment to assess how flowering duration and leafing out respond to heavy rainfall and drought, as a real world test of some of the statistical correlations found in the data set and analysis described below. 7. Research implementation and results under the program Title of your research plan: Impacts of climate variability and urbanization on Prunus yedoensis Description of the research activities: I first attempted to define an appropriate urban impact area. In order to set up an urban-rural gradient we had to identify JMA stations with similar climate and elevation with different levels of urbanization. We established three different gradients on three different latitude lines, including the following cities: 1) Matsumoto, Maebashi, Kumagaya, Utsunomiya, Mito; 2) Iida, Kofu, Choshi, Yokohama, Tokyo; 3) Hamamatsu, Shizuoka, Tateyama, Oshima. However, after creating plots of the standard deviations of the Julian day of phenological events over time for these stations, I found the variation to be too small to make statistically significant comparisons with weather data. I then decided to look not at variation in the phenological event, but at another expression of variability, flowering duration. Flowering duration indeed changes dramatically over time and in response to temperature and precipitation. A collaborator in my advisor’s phenology group, Jeff Diez, is conducting statistical analysis on models he built specifically to analyze Prunus yedoensis, and we hope to write a paper together once the analysis is completed. To date, there is little evidence for the expansion of flowering duration due to climate warming in temperate cherry trees, or for trees in general. There has also been no exploration into the effects of precipitation and extreme climate event effects on flowering duration. Using a 53-year data set of detailed flowering phenology and climate data across 74 stations in South Korea, we determined that flowering duration is increasing in tight correlation with warming temperatures. Although precipitation alone has a non-significant effect on flowering duration, heavy rainfall events and interaction effects with temperature have created some significant trends. Figure 1: Duration increases with average winter temperatures but precipitation effects on flowering duration are minor (Jeff Diez, unpublished figure)ｓ I also became involved in another project in Kobori lab in which I am one of the primary investigators. In conjunction with Sonobe-san and Taguchi-sensei we have taken a thorough population size and biodiversity census in Mitzuike Park and 11 urban dragonfly habitats in Yokohama as well as noted habitat characteristics in order to determine the success of this conservation project to date and also establish goals for future management. 20 years ago the Yokohama city government established a conservation project to create urban habitats for dragonflies, involving many local industries in the creation and management of dragonfly ponds in urban Yokohama. We have examined these 11 habitats as well as one reserve in the Green Belt of Yokohama, a potential source of dragonfly populations to the urban ponds. This source reserve, Mitzuike Park, contains three large ponds and many smaller streams and ponds, as well as a small rice paddy field totaling 16,251m2 of open water. Using mark and recapture methods we will estimate the population size of common dragonfly species at these 11 habitats. We will correlate population size to the following habitat characteristics: 1) Water quality as characterized by ORP, EC, pH, COD, nitrates, nitrites, ammonia, phosphate, temperature and turbidity, 2) Pond size and depth, 3) Pond location, 4) % of shoreline with emergent plants, 5) % of surface with floating plants, 6) % of shoreline shaded, 7) % of surface shaded, 8) % of shoreline with trees and shrubs. Although we are not finished with our analysis, we expect that there will be more dragonflies and greater diversity at ponds that are large, sunny, close to other ponds, have better water quality, and are close to Mitzuike Park and the rest of the Green Belt. RESEARCH REPORT 1. Name: Jennifer Apell （ID No.: SP10002） 2. Current affiliation: University of Florida 3. Research fields and specialties: Engineering Sciences 4. Host institution: Hokkaido University 5. Host researcher: Dr. Katsuki Kimura 6. Description of your current research My previous research explored the viability of combining anion and cation exchange resins into a single completely mixed flow reactor to remove both anionic and cationic contaminants. The two contaminants of interest, dissolved organic matter (DOM) and hardness ions, were effectively removed when used in a single reactor. The removals of DOM and hardness from the use of ion exchange resins individually and using the resins in sequence (i.e. treating the water with one type of resin followed by the other type) were comparable to the removals attained when using both resins simultaneously in a reactor. This treatment process was proven useful in treating natural water that has a high concentration of DOM and hardness, but other possible applications were considered. Since both organic matter and calcium have been shown to be major foulants in high-pressure membrane systems (nanofiltration and reverse osmosis), combined ion exchange could significantly lower the fouling of these treatment systems and possibly make them more economical to operate. 7. Research implementation and results under the program Title of your research plan: Combined Ion Exchange as a Pre- and Post-Treatment of Nanofiltration Description of the research activities: The objective of my research at Hokkaido University was to verify that combined ion exchange would alleviate the fouling of nanofiltration membranes. I prepared two types of synthetic waters to imitate concentrations found in raw drinking water 2+ 2- sources. Both synthetic waters had approximate concentrations of 20 mg/L Ca , 30 mg/L SO4 , and 4 mg/L of dissolved organic matter. The first synthetic water used Aldrich humic acid (AHA) as the source of organic matter while the second synthetic water used Suwannee River natural organic matter (SRNOM). SRNOM is derived from an aquatic source and is considered typical of aquatic organic matters. Aldrich humic acid is a peat-derived organic matter, but it has been used extensively in previous membrane fouling research. Preliminary tests were conducted to select optimum ion exchange doses for the AHA-containing synthetic water, and preliminary nanofiltration experiments were conducted to determine the volume of water to be filtered. A recovery, or the percentage of treated water collected, of 70% was chosen as the end-point for the filtration runs. The removals achieved, approximately 45% DOM and 85% calcium, in the AHA-containing water were able to decrease the fouling observed in the nanofiltration membrane. For untreated water, the flux through the membrane decreased to 42% of its initial value. When treated with combined ion exchange, the flux decreased to only 75% of its initial value. After the initial filtration, the concentrate (the fraction of water that does not pass through the membrane) of the treated water was treated again with combined ion exchange. The treated concentrate was then filtered through a new membrane. Significant flux decline was observed after filtration of 70% of the concentrate with the final flux being 50% of the initial flux. However, when the untreated concentrate was filtered through a new membrane, the final flux was 30% of the intial flux. In contrast, the synthetic water containing SRNOM experienced much less flux decline at a recovery of 70%. The final flux ranged between 77 and 84% of the initial flux for both treated and untreated waters. Despite this, the filtration of concentrates did show a considerable

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