In the continental United States, mean surface air temperature is expected to increase by up to 5°C within 100 years. With hotter temperatures, leaf budbreak is expected to occur earlier in forests, and leaf area is expected to increase in locations where temperature is limiting. The response of plant photosynthesis to hotter temperatures is less certain; plant productivity could increase or decrease. Past studies have found intraspecific variation in the responses of forest tree productivity, phenology, canopy leaf area, and leaf isoprene emission to warming, which all influence carbon uptake and yield for agricultural tree species; it is therefore important to understand not only how hot climates affect carbon uptake and biomass production between different tree species, but also in different genotypes of the same species. We conducted a common garden study at the Biosphere 2 research center near Oracle, AZ, USA. We created a hybrid poplar plantation of 168 trees, which were planted as cuttings in January 2013. The trees used in this study are comprised of 5 distinct genotypes of Populus deltoides × trichocarpa from a range of average annual air temperatures. We measured photosynthetic capacity, leaf phenological timing, canopy leaf area and aboveground woody biomass in 2014 growing season, and leaf isoprene emission in the 2015 growing season. We observed a strong effect of genotype on aboveground woody biomass increment, implying strong local adaptation to the home range and limited phenotypic plasticity in terms of physiological and biometric responses to high temperature environments. Our study suggests that genotypes from hotter home ranges are able to maintain photosynthetic capacity and canopy leaf area late into the growing season, despite high temperatures, and thus produce more aboveground woody biomass. This study may have implications for agricultural management—as temperatures warm where managers currently grow hybrid poplar for agricultural or other purposes, the genotypes from those home ranges would likely have reduced yield; managers could investigate the use of genotypes from home ranges with higher average temperatures to replace the vulnerable local varieties.

Electron spin echo envelope modulation (ESEEM) spectroscopy is widely used to study the radical pairs created during the primary steps of photosynthesis. In this thesis the analysis of ESEEM spectra is improved, and some new applications and variations of this experiment suggested. Experimental spectra from species such as P⁺Q^-_A, the secondary radical pair formed in the reaction centre of the bacterium Rhodobacter sphaeroides, give information about the exchange and dipolar couplings between the radicals. The model used to analyse the data affects the results; this thesis suggests two improvements. First, the effect of anisotropic hyperfine couplings in the radicals is considered by the addition of a single spin-1/2 nucleus to the model. This approach suggests that previous models neglecting the effect of nuclei may have been slightly in error. Secondly, several model fittings are performed in the time domain. This approach avoids the Fourier transformation to the frequency domain so that experimental dead-time does not corrupt the data. An excellent fit to experimental data is found with a model containing one spin-1/2 nucleus on each radical. The hyperfine coupling parameters resulting from the fit are consistent with independent experimental results. Use is made of the method of Cramér-Rao lower bounds to assess the precision to which experimental parameters are determined from a time domain curve fitting. It is shown that the lower bounds may also be used to determine the optimum sampling strategy for the experiment. An example is given of the novel use of ESEEM to determine the distance between the radicals in the strongly coupled, uncorrelated radical pair Q^-_AQ^-_B ESEEM has not yet been used for this purpose, and the simulated spectra produced here indicate that the experiment could be used to evaluate the dipolar coupling and hence the inter-radical distance. This thesis considers the possibility of performing ESEEM at higher frequencies than are usually considered. Calculations show that the increased resolution of the g-tensors allow an experiment performed at the W-band frequency of 95 GHz to make a correlation between the relative orientations of the radicals and the dipolar axis, information which has previously been unavailable from a single experiment.

京都大学 / 新制・課程博士 / 博士(人間・環境学) / 甲第23993号 / 人博第1045号 / 新制||人||245(附属図書館) / 2022||人博||1045(吉田南総合図書館) / 京都大学大学院人間・環境学研究科相関環境学専攻 / (主査)教授 瀬戸口 浩彰, 教授 市岡 孝朗, 教授 宮下 英明, 准教授 西川 完途, 准教授 池田 啓 / 学位規則第4条第1項該当 / Doctor of Human and Environmental Studies / Kyoto University / DGAM

No description available.

We present a novel thylakoid based bio-solar cell capable of generating a photoelectric current of    0.7 µA/cm2. We have introduced an electro conductive polymer, PEDOT-S, to the thylakoid membrane. PEDOT-S intervenes in the photosynthesis, captures electrons from the electron transport chain and transfers them directly across the thylakoid membrane, thus generating a current. The incorporation of the electro conductive polymer into the thylakoid membrane is therefore vital for the function of the bio-solar cell. A liposomal model system based on liposomes formed by oleic acid was used to develop and study the incorporation of PEDOT-S to fatty acid membranes. The liposomes allow for a more controllable and easily manipulated system compared to the thylakoid membrane. In the model system, PEDOT-S could successfully be incorporated to the membrane, and the developed methods were applied to the real system of thylakoid membranes. We found that a bio-compatible electrolyte and redox couple was required for this system to function. The final thylakoid based bio-solar cell was evaluated according to performance and reproducibility. We found that this bio-solar system can generate a low but reproducible current.

Purple nonsulfur bacteria are a group of extraordinary metabolic diverse bacteria. They can grow photoautotrophically, photoheterotrophically , chemoheterotrophically or chemoautotrophically. Under various conditions, they can enjoy exceptional flexibility within each of these modes of metabolism. Due to the special physical characteristics properties, they had attracted scientist¡¦s attention in resent years. These bacteria are widely distributed in nature such as lakes, water ponds, coastal lagoons or high concentration organic waste lagoons. Lotus Pond, located in northern Kaohsiung City, is a serious eutrophied artificial lake. Because of receiving sufficient light and having been polluted by significant amounts of soluble organic matter, the ecology of the lake is suitable for the growth of purple nonsulfur bacteria. In the study, the lake water and sediments by using a Winograsdsky column, we successfully isolated 16 strains bacteria from the Lotus Pond. We also amplified the 16S-rDNA fragments of these strains by PCR and sequenced these PCR products, then aligned these sequences with the data of GeneBank. We affirmed that the 16 isolated strains belong to purple nonsulfur bacteria. From phylogenetic analysis, these 16 strains belong to the following three groups of bacteria: Rhodopseudomonas palustris, Rubrivivax gelatinosus, and Rhodobacter sphaeroides. Characteristic studies of these strains, we found that all isolated strains are Gram negative bacteria and contain bacteriochlorophyll a. The strains that belong to R. palustris and R. sphaeroides group can use several different types of short chain organic acid as their carbon source and have denitrification ability. However, only the strains belong to R. palustris group are able to use the aromatic compound benzoate. From salt tolerant studies, we found the strains in R. sphaeroides group can grow well in 3% NaCl, and both R. palustris and R. gelatinosus group can only grow in 1% NaCl.

Photobiological hydrogen production from organic materials occurs with the help of illumination and under aerobic conditions within photobioreactors. Novel designs are needed in order to increase the light conversion efficiency and to improve the biological hydrogen production. In this thesis, purple non sulfur bacteria Rhodobacter sphaeroides O.U. 001 was employed as the hydrogen producing microorganism. Two different types of photobioreactors, namely oscillatory helical photobioreactor and recycling helical bioreactor, were devised and successfully operated for bacterial growth and hydrogen production. Total liquid capacity of the pneumatically driven oscillatory flow helical tubular photobioreactor was 11.5 L, and 4.5 L of which was occupied by the bacterial culture. The bacteria grew very well both in malate-based and acetate-based media under nitrogen atmosphere. The bacteria sustained their vitality 24 days before the system was shut down. The recycling helical tubular photobioreactor, which was developed for hydrogen production, had a fully occupied total volume of 6.5L. The bacteria produced approximately 1.9L of hydrogen in four days on malate-based media. The hydrogen production rate was 0.009LH2/Lculture.h. The effects of molecular nitrogen gas and the sodium glutamate concentration on the growth of hydrogen producing photosynthetic bacteria Rhodobacter sphaeroides O.U.001 in the reactor were also examined in 500ml-bottles. The bacterial growth curves did not show any difference at the control medium containing 15mM of acetate and 10 mM of sodium glutamate. However, other bottles containing a lesser amount of N-source was found to grow earlier under the nitrogen atmosphere. Besides, even a 15/2 acetate/sodium glutamate ratio was observed to be sufficient to grow the bacteria for inoculation, and to spend extra sodium glutamate was not necessary. The novel designs developed in this study aim to improve the biological hydrogen production by photosynthetic bacteria, and to provide new ways in adaptation of photobiological systems to outdoor conditions for large-scale applications.

Heavy metals are one of the most important environmental pollutants. In recent years, many low cost stretages of bioremediation for contaminated sites by heavy metals, such as fungi, bacteria and plants have been investigated for their biosorption capacity towards heavy metals. The uses of plant species for remediate contaminated sites by heavy metals are so called phytoremediation. The purpose of the first parts of this study are to (1) evaluate bioavailability of Cadmium (Cd) in contaminated soil and phytoremediation potential by three plant species, Vetiveria zizanioides, Pteris multifida, and Alternanthera philoxeroides (Mart.), and (2) realized the influence of photosynthetic bacteria (PSB) on the uptake of Cd in the three species. The results showed that the Alternanthera philoxeroides (Mart.) could accumulate the highest concentration of Cd among the three species, in which the Cd concentration of plant tissue increased with the concentration in soil. The highest concentration of Cd (164.9 mg kg-1) was found in the below-ground parts of Alternanthera philoxeroides (Mart.) at the 8th week of culturing period. However, the species of Vetiveria zizanioides could accumulate the largest total Cd, up to 547.5 £gg/ plant, which thus extracted the greatest amounts of Cd from the soil. Therefore, in the first part of this study the species of Vetiveria zizanioides was concluded to be the best accumulator among the three plant species. In addition, the concentration of Cd in the species of Pteris multifida was found significantly increased after PSB was added into the soil, but the plants died later due to Cd stress. The experimental results also showed that PSB seemed to be not suitable for each species used in this study to accumulate Cd from Cd-contaminated soil. In the second part of this research, both pot and field experiments were conducted to (1) evaluate bioavailability of copper (Cu), lead (Pb) and zinc (Zn) in contaminated soil and phytoremediation potential by domesticated plants, Bidens pilosa and Passiflora foetida inoculated with arbuscular mycorrhizal (AM) fungi, and to (2) compare the results of pot and field experiments. The plant species of Bidens pilosa inoculated with AM fungi had significantly higher Cu concentrations in the shoots and roots than non-inoculated plants. The plant species of Passiflora foetida inoculated with AM fungi also had significantly higher Cu and Pb concentrations in the roots than non-inoculated plants. When we found that the root dry weight of Passiflora foetida inoculated with AM fungi dramatically increased, the concentrations of Cu, Pb and Zn in the root of the plant species increased by 9-14 times, comparing with the plants without inoculation of AM fungi. The AM fungi have potential either to promot plant growth or to increase heavy metal accumulation. The values of element translocation proportion from root to shoot was Zn>Cu>Pb for the plant species in both pot and field experiments. For both experiments, the results of pot test and field test were significantly different. The concentrations of pot tests were found higher than the field tests, and some values of pot tests were even found significantly greater than those in the field tests. In the third part of this study, the field experiments were conducted to test the feasibility of using domesticated vegetations for phytoremediation of the contaminated farmland. The objectives of this study were (1) to acquire information about the ability of five plant species growing wild in the polluted area to accumulate Cu, Pb and Zn, (2) to investigate the season effects on phytoremediaton of five plant species and evaluate the total uptake of heavy metal, and (3) to run both pot tests and a field trial of phytotremediation to compare their differences. The experimental results showed that three maximum toxic elements in a pot were 3020 mg kg-1 Pb, 232 mg kg-1 Cu and 1012 mg kg-1 Zn respectively. The Cu concentrations of the five plant species collected from the polluted plots ranged from 0.7 to 17.43 mg kg-1. The range of variation of Pb in plant tissues was measured varied from 2.29 to 81.65 mg kg−1, while a wide range of Zn concentrations was found from 12.84 to 192.85 mg kg-1 among the plants collected at the contaminated plots. In comparison to winter season, the Zn concentrations in Broussonetia papyrifera, Passiflora foetida and Saccharum sinensis collected in summer season was significantly higher. The higher Cu concentrations were obtained in both plant species of Bidens pilosa and Mimosa diplotricha in summer season. However, Pb concentrations in Saccharum sinensis collected in winter were significantly higher than those in the same plant species collected in summer. Bidens pilosa was also found having the highest total amount of Cu and Zn. The highest total amount of Pb was found in Mimosa diplotricha. For both plant species, both of the pot and field tests were different.

Thesis (Ph. D.)--University of California, San Diego, 2000. / Vita. Includes bibliographical references.

Tiriant didėjančių temperatūrų ir drėgmės deficito poveikį sėjamųjų žirnių biometriniams ir biocheminiams rodikliams, bandymai atlikti LSDI Augalų fiziologijos laboratorijos fitotroniniame komplekse 2009 metais. Tirta didėjančių temperatūrų ir drėgmės deficito įtaka sėjamųjų žirnių (Pusum sativum L.) 'Gloriosa' antžeminės dalies augimui, žaliųjų bei sausųjų medžiagų kaupimuisi antžeminėje dalyje, asimiliaciniam lapų plotui ir fotosintetinių pigmentų kiekiui. Atlikus tyrimus nustatyta, kad, didėjant temperatūrai ir mažėjant substrato drėgmei chlorofilų a ir b bei karoteno kiekis sėjamųjų žirnių daiguose, didėja. Iš tyrimų duomenų matyti, kad didžiausias sausųjų medžiagų kiekis buvo daiguose, kurie augo normalaus drėgnio (40 - 45%) substrate, aukštesnėje - 25/18 °C temperatūroje. Sėjamųjų žirnių didžiausias daigų lapų plotas buvo prie žemesnės temperatūros ir normalaus substrato drėgnio (40 - 45%). Aukščiausi daigai buvo normalaus drėgnio (40 - 45%) substrate ir prie - 25/18 °C temperatūros. Tyrimai parodė, kad kompleksinis drėgnio ir aukštos temperatūros poveikis skatina žirnių daigų augimą. Taip pat iš duomenų matosi, kad normalus (40 - 45%) substrato drėgnis ir aukštesnė - 25/18 °C temperatūra skatina asimiliacinį žirnių daigų lapų plotą. / A study of rising temperatures and water deficit effects on pea biometric and biochemical characteristics was conducted at LSDI. It was accomplished at Plant Physiology Laboratory fitotronical complex in 2009. The research was made on the influence of rising temperatures and water deficit on pea (Pisum sativum L.) 'Glorioso' canopy growth, green and dry matter accumulation in terrestrial, assimilated leaf area and photosynthetic pigment content. The investigation showed that with increasing temperature and decreasing the substrate moisture of chlorophylls a and b and carotene content of pea shoots have been rising. The survey data shows that the highest dry material concentrations was of the shoots, which grew at normal humidity (40 - 45%) substrate and higher temperature - 25/18 ° C. The highest pea shoots leaf area was lower at normal temperature and substrate moisture (40 - 45%). Tallest plants were normal humidity (40 - 45%) and the substrate - 25/18 ° C temperature. Studies have shown that a complex of high humidity and temperature on pea plants promote growth. Also the data shows that normal (40 - 45%) substrate moisture content and higher - 25/18 ° C temperature promotes assimilation of pea sprouts leaves area.