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1.
Nguyen Thai Hoa Tomoko Hasegawa Yuzuru Matsuoka 《Mitigation and Adaptation Strategies for Global Change》2014,19(1):15-32
Agriculture, Forestry and Other Land Use (AFOLU) sectors account for 53 % of the domestic greenhouse gas emissions (GHG) in Vietnam in 2000. However, due to political focus on adaptation, Vietnamese government has not formulated particular policy on mitigation in the sectors. This study aims to identify and assess mitigation potential in AFOLU sectors in Vietnam up to 2030 using AFOLU Bottom-up model. Therefore, the results can help government towards building mitigation strategies in the country. The methodology involves: (1) development of future assumptions of crops harvested areas, livestock population and area of land use and land use change and (2) identification of mitigation countermeasures with high potential and assessment of their cost-effectiveness. In 2030, 11 MtCO2eq/year of emission can be reduced by no-regret countermeasures which take zero or negative cost. In the case of full application of countermeasures, 48 MtCO2eq/year can be reduced compared to the baseline emission level. Mitigation countermeasures, which have great contribution for GHG reduction in Vietnam, are midseason drainage in rice paddy (7 MtCO2eq/year), off-season incorporation of rice straw (3 MtCO2eq/year) and conservation of existing protection forests (17 MtCO2eq/year). Based on our findings, a package of mitigation countermeasures at 10 USD/tCO2eq is expected to have the most economic efficiency and high mitigation for GHG mitigation in AFOLU sectors in Vietnam. 相似文献
2.
Intraspecific variation in the patterns of parental care has been observed in a variety of animals; however, the possibility of parental care by a non-caregiving parent of uniparental species has not been thoroughly explored. In the coral-reef damselfish, Dascyllus albisella, only males normally exhibit parental care. In this study, we examined the response of females of this species to egg predators after experimental male removal and an elevated level of egg predation, at two small patch reefs (reefs 1 and 2) in Hawaii. We tested theoretical expectations that a nest was defended only by females which had spawned in the nest, and that larger females had a higher likelihood of defense than smaller females. A nest was defended against egg predators more frequently by females that had spawned in that nest than would be expected by chance. Not all females that had spawned in a given nest participated in defense. There was a positive association between female body length and the likelihood of defense at reef 2, but not at reef 1. Within a set of females that had spawned in the same nest during the same nesting cycle, defending females had larger body lengths than non-defending females at reef 2 but not at reef 1. Lack of association between female size and likelihood of defense at reef 1 was unexpected, but may correlate with the smaller average female size and smaller size differences among females on that reef. 相似文献
3.
Constructed wetlands are considered to be important sources of nitrous oxide (N(2)O). In order to investigate the contribution of nitrification in N(2)O formation, some environmental factors, plant species and ammonia-oxidizing bacteria (AOB) in active layers have been compared. Vegetation cells indicated remarkable effect of seasons and different plant species on N(2)O emission and AOB amount. Nitrous oxide data showed large temporal and spatial fluctuations ranging 0-52.8 mg N(2)O m(-2)d(-1). Higher AOB amount and N(2)O flux rate were observed in the Zizania latifolia cell, reflecting high potential of global warming. Roles of plants as ecosystem engineers are summarized with rhizosphere oxygen release and organic matter transportation to affect nitrogen transformation. The Phragmites australis cell contributed to keeping high T-N removal performance and lower N(2)O emission. The distribution of AOB also supported this result. Statistical analysis showed several environmental parameters affecting the strength of observed greenhouse gases emission, such as water temperature, water level, TOC, plant species and plant cover. 相似文献
4.
Shevchenko Pavel V. Murakami Daisuke Matsui Tomoko Myrvoll Tor A. 《Environmental Economics and Policy Studies》2022,24(3):459-476
Environmental Economics and Policy Studies - The classical DICE model is a widely accepted integrated assessment model for the joint modeling of economic and climate systems, where all model state... 相似文献
5.
Several green turtle (Chelonia mydas) nesting populations have been reported in the northwestern Pacific region, the northernmost limit of its distribution range. However, the population history in this region as a whole is not well understood. To clarify how the green turtle nesting populations have evolved in the northwestern Pacific region, the genetic composition of mitochondrial DNA control region sequences in the northwestern Pacific was compared with that of the other Pacific populations. We analyzed 302 samples from the northwestern Pacific rookeries, including 78 newly collected samples from rookeries in the Ryukyu Archipelago, Japan (from 24.27°N, 123.76°E to 28.45°N, 129.61°E). Our results revealed that the northwestern Pacific populations consisted of one highly endemic lineage (Clade IV) in the northwestern Pacific rookeries and two other lineages (Clades I and V) which were widely observed in other Pacific populations. We concluded that the highly endemic lineage indicated that a refugial population existed in this region during the Last Glacial Maximum, and the other two lineages indicated that colonization from populations at lower latitudes occurred during interglacial periods. The green turtle nesting populations in the present periphery of their distribution range had been thought to have their origin in colonization from lower latitudes, which served as refugia during glacial periods. However, the present results indicated that the northwestern Pacific peripheral populations have been maintained on the evolutionary timescale of this species and should be treated as long-term conservation resources. 相似文献
6.
Positive buoyancy in eel leptocephali: an adaptation for life in the ocean surface layer 总被引:1,自引:0,他引:1
Katsumi Tsukamoto Yoshiaki Yamada Akihiro Okamura Toyoji Kaneko Hideki Tanaka Michael J. Miller Noriyuki Horie Naomi Mikawa Tomoko Utoh Satoru Tanaka 《Marine Biology》2009,156(5):835-846
Many planktonic organisms have adaptations such as floats or lighter substances to obtain buoyancy to help them remain in
the surface layer of the ocean where photosynthetic primary production occurs and food is most abundant. The almost totally
transparent eel larvae, called leptocephali, are a unique member of the planktonic community of the surface layer, but their
ecology and physiology are poorly understood. We conducted a comparative study on the specific gravity of planktonic animals
including 25 taxa of 7 phyla of marine invertebrates and 6 taxa of leptocephali (vertebrate) to gain a broad perspective on
the buoyancy of the eggs and larval stages of the Japanese eel. The specific gravity values of the various freshly caught
marine invertebrate taxa varied widely from 1.020 to 1.425, but leptocephali had some of the lowest values (1.028–1.043).
Artificially cultured live leptocephali had even greater buoyancies with specific gravities of 1.019–1.025 that were close
to or lower than seawater, and their buoyancy showed ontogenetic changes among the different early life history stages. Leptocephali
appear to have a unique mechanism of buoyancy control by chloride cells all over body surface through osmoregulation of body
fluid contained in the extracellular matrix of transparent gelatinous glycosaminoglycans filling their bodies. This adaptation
is likely a key factor for their survival by helping them to remain in the surface layer where food particles are the most
abundant, while being transparent for predator avoidance. The ontogenetic change in buoyancy of eel eggs, leptocephali and
glass eels likely enhances their larval survival, transport, and recruitment to terrestrial freshwater habitats. 相似文献
7.
To apply PET depolymerization in supercritical methanol to commercial recycling, the benefits of supercritical methanol usage in PET depolymerization was investigated from the viewpoint of the reaction rate and energy demands. PET was depolymerized in a batch reactor at 573 K in supercritical methanol under 14.7 MPa and in vapor methanol under 0.98 MPa in our previous work. The main products of both reactions were the PET monomers of dimethyl terephthalate (DMT) and ethylene glycol (EG). The rate of PET depolymerization in supercritical methanol was faster than that of PET depolymerization in vapor methanol. This indicates supercritical fluid is beneficial in reducing reaction time without the use of a catalyst. We depicted the simple process flow of PET depolymerization in supercritical methanol and in vapor methanol, and by simulation evaluated the total heat demand of each process. In this simulation, bis-hydroxyethyl terephthalate (BHET) was used as a model component of PET. The total heat demand of PET depolymerization in supercritical methanol was 2.35 x 10(6)kJ/kmol Produced-DMT. That of PET depolymerization in vapor methanol was 2.84 x 10(6)kJ/kmol Produced-DMT. The smaller total heat demand of PET depolymerization in supercritical methanol clearly reveals the advantage of using supercritical fluid in terms of energy savings. 相似文献
8.
Tomoko Yoshiki Banri Yamanoha Tomohiko Kikuchi Akio Shimizu Tatsuki Toda 《Marine Biology》2009,156(2):97-106
The effect of hydrostatic pressure on embryonic development of the calanoid copepod Calanus sinicus was studied. Differences of pressure effect among blastomere stages, 1-cell, 2-cell, 4-cell, 8-cell, 16-cell, blastula and
limb-bud stage, were examined under two pressurizing conditions, abruptly (10 atm/min) and gradually (0.1 atm/min) increasing.
Egg hatching success, deformity frequency and apoptotic cell degradation of hatched nauplii were examined. Egg hatching success
rate was not significantly different between blastomere stages, and also between pressurizing conditions. Deformity frequencies
of hatched nauplii were low in the early 1-cell and 2-cell stages, and high in the later blastula and limb-bud stages, in
both abrupt and gradual pressurizing conditions. On the other hand, in regard to difference in pressurizing conditions, deformity
frequency in gradual pressurizing was significantly higher than that in abrupt pressurizing rate. Gradual pressure increase
seems to be more harmful to C. sinicus eggs than abrupt pressure change. Apoptosis induced in nauplii by hydrostatic pressure was detected for the first time in
marine zooplankton. The embryos of C. sinicus are sensitive to pressure variations, that is, these embryos are supposed to sink to deeper waters, incurring greater risk
of having deformities. In the field, C. sinicus ascend to the surface and spawn at night. By looking from this upward behavior, eggs are spawned at lower pressure and warmer
temperature. Probably, the harmless low pressure and warm temperature lead eggs to hatch early and to recruit successfully. 相似文献
9.
Tomoko Yoshiki Banri Yamanoha Tomohiko Kikuchi Akio Shimizu Tatsuki Toda 《Marine Biology》2008,156(2):97-106
The effect of hydrostatic pressure on embryonic development of the calanoid copepod Calanus sinicus was studied. Differences of pressure effect among blastomere stages, 1-cell, 2-cell, 4-cell, 8-cell, 16-cell, blastula and limb-bud stage, were examined under two pressurizing conditions, abruptly (10 atm/min) and gradually (0.1 atm/min) increasing. Egg hatching success, deformity frequency and apoptotic cell degradation of hatched nauplii were examined. Egg hatching success rate was not significantly different between blastomere stages, and also between pressurizing conditions. Deformity frequencies of hatched nauplii were low in the early 1-cell and 2-cell stages, and high in the later blastula and limb-bud stages, in both abrupt and gradual pressurizing conditions. On the other hand, in regard to difference in pressurizing conditions, deformity frequency in gradual pressurizing was significantly higher than that in abrupt pressurizing rate. Gradual pressure increase seems to be more harmful to C. sinicus eggs than abrupt pressure change. Apoptosis induced in nauplii by hydrostatic pressure was detected for the first time in marine zooplankton. The embryos of C. sinicus are sensitive to pressure variations, that is, these embryos are supposed to sink to deeper waters, incurring greater risk of having deformities. In the field, C. sinicus ascend to the surface and spawn at night. By looking from this upward behavior, eggs are spawned at lower pressure and warmer temperature. Probably, the harmless low pressure and warm temperature lead eggs to hatch early and to recruit successfully. 相似文献
10.
Tomoko Oguri Jun Yoshinaga Yayoi Suzuki Hiroaki Tao Tetsuya Nakazato 《Journal of environmental science and health. Part. B》2017,52(6):425-429
Inorganic arsenic (InAs) is a ubiquitous metalloid that has been shown to exert multiple adverse health outcomes. Urinary InAs and its metabolite concentration has been used as a biomarker of arsenic (As) exposure in some epidemiological studies, however, quantitative relationship between daily InAs exposure and urinary InAs metabolites concentration has not been well characterized. We collected a set of 24-h duplicated diet and spot urine sample of the next morning of diet sampling from 20 male and 19 female subjects in Japan from August 2011 to October 2012. Concentrations of As species in duplicated diet and urine samples were determined by using liquid chromatography-ICP mass spectrometry with a hydride generation system. Sum of the concentrations of urinary InAs and methylarsonic acid (MMA) was used as a measure of InAs exposure. Daily dietary InAs exposure was estimated to be 0.087 µg kg?1 day?1 (Geometric mean, GM), and GM of urinary InAs+MMA concentrations was 3.5 ng mL?1. Analysis of covariance did not find gender-difference in regression coefficients as significant (P > 0.05). Regression equation Log 10 [urinary InAs+MMA concentration] = 0.570× Log 10 [dietary InAs exposure level per body weight] + 1.15 was obtained for whole data set. This equation would be valuable in converting urinary InAs concentration to daily InAs exposure, which will be important information in risk assessment. 相似文献