Microzooplankton standing crop in the western subtropical pacific off the Bonin Islands in winter, 1980     

Yoshinari Endo  Hiroshi Hasumoto  Akira Taniguchi 《Journal of Oceanography》1983,39(4):185-191

Quantitative data on the vertical distribution and biomass of microzooplankton are presented for the western subtropical Pacific west of the Bonin Islands in winter. Microzooplankton other than foraminifera and radiolarians showed similar vertical distribution to chlorophylla. Among microzooplankters, naked ciliates, tintinnids and copepod nauplii were dominant components both in number and volume. Naked ciliates were the most dominant, comprising 82.2 % and 47.7 % of the total microzooplankton by number and volume, respectively. Copepod nauplii, occupying less than 10 % by number, accounted for 35.7 % of the volume of all microzooplankton. Tintinnids contributed less to the microzooplankton standing crop, 12.6 % of the total by number and 17.3 % by volume. Calculated microzooplankton wet weight varied from 0.84 to 1.80 g m^?2 and corresponded to 9.9–18.1 % of net zooplankton weight. The relative abundance of microzooplankton to net zooplankton in this study is comparable to that previously reported in the tropical and subtropical Pacific Ocean, but a little higher than in oceanic subarctic areas.  相似文献   

Can the visualization of rip currents prevent drowning accidents? Consideration of the effect of optimism bias     

Endo  Shintaro  Shimada  Ryo  Ishikawa  Toshinori  Komine  Tsutomu 《Natural Hazards》2022,110(3):2017-2033

Drowning accidents at beach in Japan are caused by rip currents. To reduce these accidents, a new technology that can detect rip currents and notify beachgoers by using the Internet of Things (IoT) and Artificial Intelligence (AI) was proposed. However, studies on the effect of visualizing rip currents or considering the effect of optimism bias have not been conducted. This study investigates if visualization of rip currents might help in preventing drowning accidents, while considering the effect of optimism bias. The participants were 90 Japanese beachgoers. They were asked to answer questions based on their knowledge of the beach and rip currents, their optimism bias regarding rip currents, and awareness with or without visualization. The results of the analyses suggest that despite optimism bias, the visualization of rip currents increases the tendency of beachgoers to perceive and avoid rip currents. As described above, it was found that by visualizing the rip current, beachgoers were able to perceive and avoid rip currents. In addition, an understanding of rip currents is positively related to the intent to avoid rip currents even when rip currents are visualized. Therefore, it is necessary not only to enhance the avoidance tendency by visualizing rip currents, but also to further enhance knowledge of beachgoers to deepen the understanding of rip currents including the danger associated and methods to avoid them.

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Consequences of actor level livelihood heterogeneity for additionality in a tropical forest payment for environmental services programme with an undifferentiated reward structure     

Peter Newton  Elizabeth S. Nichols  Whaldener Endo  Carlos A. Peres 《Global Environmental Change》2012,22(1):127-136

Primary tropical forests provide crucial environmental services, including carbon storage and hydrological regulation. Options for promoting forest conservation include payments for environmental services (PES) programmes that provide financial incentives to local actors, in exchange for reduced forest clearance. The success of voluntary PES (defined in terms of avoided primary forest conversion) is contingent upon behavioural changes in enrolled actors. As both the degree of enrolment and likelihood of sustained behavioural change depend upon how PES compensation structures interact with existing actor economies, local heterogeneity in livelihood strategies may play a strong role in the ultimate success of PES programmes, particularly when compensation is not differentiated with respect to opportunity costs. We examined the influence of livelihood heterogeneity on the potential success of a deforestation-reduction PES with an undifferentiated reward structure. We collected socioeconomic and demographic data at the household and community levels across two large Amazonian extractive reserves where a spatially extensive PES programme (Bolsa Floresta) operates. We show that demographic and socioeconomic status varies widely across households and communities, and found that both households and communities that are most and least likely to convert primary forest receive similar financial incentives. Those households most engaged in manioc agriculture (the primary driver of local primary forest conversion) both benefitted from the highest annual incomes and incurred the greatest opportunity costs. We show that avoided primary forest conversion could be greatly increased with differentiated payment structures adjusted for local differences in opportunity costs and livelihood strategies, and present two metrics that could help to achieve that goal.  相似文献   

Barchan‐shaped ripple marks in a wave flume     

Noritaka Endo  Hidehito Kubo  Tsuguo Sunamura 《地球表面变化过程与地形》2004,29(1):31-42

Barchans, isolated crescent‐shaped bedforms, are believed to be formed under almost unidirectional wind or water ?ows and limited sand supply. The formation of barchan morphologies under the action of purely oscillatory wave motion has not yet been fully investigated. The present study attempted to form barchan topography in a wave ?ume and to compare this with barchans in the ?eld. Barchan morphologies of ripple size, called the barchan ripples, were generated from a ?at bed by the action of waves. The horn width, the distance between horn tips, of the barchan ripples increased linearly with an increase in the total length, the overall length projected on the centre line of the barchan, with a coef?cient common to barchan dunes in deserts. The ratio of horn length to horn width of the barchan ripples was smaller than that of barchan dunes, but similar to that of subaqueous barchans in the ?eld. The longer the wave period was, the larger the ratio of the body length to horn width became. Most subaqueous barchans formed under waves (in the laboratory) and unidirectional ?ows (in the ?eld) had blunter horns than subaerial barchans. The shape of the barchan ripples changed with wave period. The outer rim became rounder with increasing wave period. The relationship between the base area and the height of barchan morphologies seems to be linear, with a constant coef?cient for the scale from ripples to dunes. The barchan ripples showed a linear relationship between the height and the horn width, similar to that for barchan dunes. The migration speed of the barchan ripples was proportional to the cube of the ?ow velocity and was inversely proportional to height. The same relation with a different value of the coef?cient was obtained for barchan dunes. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

Sequencing Batch Experiments with activated Sludge Consuming Glucose and Phenol     

V. A. Vavilin  A. Endo  J. Matsumoto 《洁净——土壤、空气、水》1987,15(6):665-668

During the rather short solids retention time θ = 1.25 d phenol is not utilized by activated sludge and only glucose is consumed during the sequencing batch experiments. After glucose consumption the residual COD concentration (COD = 820 mg/l) is represented mainly by the phenol concentration. During the rather long solids retention time θ = 8 d phenol is consumed by activated sludge as well as glucose. In this case the residual COD concentration is much smaller (COD = 46 mg/l) and the ratio BOD₅/COD = 0.1 is small, too. The general model of biological treatment suggested by one the authors earlier can describe the sequencing batch experimental data rather well.  相似文献   

Erratum to: “Partial derivative of love numbers”     

S. Okubo  M. Saito  Takesi Endo  Shuhei Okubo 《Journal of Geodesy》1984,58(1):73-74

A small error in the computations ofOkubo andSaito has been corrected. The correction removes certain previously peculiar results and slightly affects partials within the inner core. The online version of the original article can be found at  相似文献   

Ion upflow and downflow at the topside ionosphere observed by the EISCAT VHF radar   总被引：2，自引：0，他引：2  

M. Endo  R. Fujii  Y. Ogawa  S. C. Buchert  S. Nozawa  S. Watanabe  N. Yoshida 《Annales Geophysicae》2000,18(2):170-181

We have determined the MLT distribution and KpK_P dependence of the ion upflow and downflow of the thermal bulk oxygen ion population based on a data analysis using the EISCAT VHF radar CP-7 data obtained at Tromsø during the period between 1990 and 1996: (1) both ion upflow and downflow events can be observed at any local time (MLT), irrespective of dayside and nightside, and under any magnetic disturbance level, irrespective of quiet and disturbed levels; (2) these upflow and downflow events are more frequently observed in the nightside than in the dayside; (3) the upflow events are more frequently observed than the downflow events at any local time except midnight and at any K_P level and the difference of the occurrence frequencies between the upflow and downflow events is smaller around midnight; and (4) the occurrence frequencies of both the ion upflow and downflow events appear to increase with increasing KP level, while the occurrence frequency of the downflow appears to stop increasing at some KP level  相似文献   

Morphological analysis of olivine grains annealed in an iron‐nickel matrix: Experimental constraints on the origin of pallasites and on the thermal history of their parent bodies     

Kazuto SAIKI  Didier LAPORTE  Daniel VIELZEUF  Satoru NAKASHIMA  Pierre BOIVIN 《Meteoritics & planetary science》2003,38(3):427-444

Abstract— Two types of pallasites can be distinguished on the basis of the grain shape of olivine (rounded or angular). It has been suggested that these two types of textures resulted from different degrees of annealing at high temperature in the parent body. In order to characterize the kinetics of rounding of olivine grains in an Fe‐Ni matrix, we carried out a series of annealing experiments using a mixture of olivine and Fe‐Ni powder. We were able to reproduce, at a miniature scale, the range of textures in pallasites. The rate of rounding was rapid enough to be observed and measured at the scale of a few micrometers to 20 μm, even though the experiments were performed below the solidus of the Fe‐Ni metal. For instance, grains ?14 mm in diameter became nearly spherical within 7 days at 1400°C. For the morphological analysis of olivine grains, we used two independent techniques: the “critical diameter method” and the “Gaussian diffusion‐resample method,” a new technique specially developed for our study. Both techniques indicate that the rounding time scale is proportional to the cube of the grain size and that morphological adjustments in our experiments occurred by volume diffusion in the olivine lattice, not by surface diffusion along the olivine‐metal boundaries. We used our experimental data to estimate the time scales required for the development of olivine‐metal textures in natural pallasites. We determined that small scale rounding of olivine grains in a solid metal matrix can be produced within relatively short time intervals: ?100 years to produce rounded olivine grains 0.1 mm in radius at 1300–1400°C.  相似文献   

Granulite formation in a Gondwana fragment: petrology and mineral equilibrium modeling of incipient charnockite from Mavadi, southern India     

Takahiro Endo  Toshiaki Tsunogae  M. Santosh  Hisako Shimizu  E. Shaji 《Mineralogy and Petrology》2013,107(5):727-738

We report a new occurrence of incipient charnockite from Mavadi in the Trivandrum Granulite Block (TGB), southern India, and discuss the petrogenesis of granulite formation in an arrested stage on the basis of petrography, geothermobarometry, and mineral equilibrium modeling. In Mavadi, patches and lenses of charnockite (Kfs?+?Qtz?+?Pl?+?Bt?+?Grt?+?Opx?+?Ilm?+?Mag) of about 30 to 220 cm in length occur within Opx-free Grt-Bt gneiss (Kfs?+?Qtz?+?Pl?+?Bt?+?Grt?+?Ilm). The application of mineral equilibrium modeling on the charnockite assemblage in the NCKFMASHTO system to constrain the conditions of charnockitization defines a P–T range of 800 °C at 4.5 kbar to 850 °C at 8.5 kbar, which is broadly consistent with the results from the conventional geothermobarometry (810–880 °C at 7.7–8.0 kbar) on these rocks. The P–T conditions are lower than the peak metamorphic conditions reported for the ultrahigh-temperature granulites from this area (T?>?900 °C). The heterogeneity in peak P–T conditions within the same crustal block might be related to local buffering of metamorphic temperatures by the Opx-Bt-Kfs-Qtz assemblage. The result of T versus mole H₂O (M(H₂O)) modeling demonstrated that the Opx-free assemblage in the Grt-Bt gneiss is stable at M(H₂O)?=?0.3 to 1.5 mol%, and orthopyroxene occurs as a stable mineral at M(H₂O) <0.3 mol%, which is consistent with the petrogenetic model of incipient charnockite related to the lowering of the water activity and stabilization of orthopyroxene through the breakdown of biotite by dehydration caused by the infiltration of CO₂-rich fluid from external sources. We also propose a possible alternative mechanism to form charnockite from Grt-Bt gneiss through slight variations in bulk-rock chemistry (particularly for the K- and Fe-rich portion of Grt-Bt gneiss) that can enhance the stability of orthopyroxene rather than that of biotite, with K-metasomatism playing a possible role.  相似文献   

A new approach to develop the Raman carbonaceous material geothermometer for low‐grade metamorphism using peak width     

Yui Kouketsu  Tomoyuki Mizukami  Hiroshi Mori  Shunsuke Endo  Mutsuki Aoya  Hidetoshi Hara  Daisuke Nakamura  Simon Wallis 《Island Arc》2014,23(1):33-50

The Raman spectra of carbonaceous material (CM) from 19 metasediment samples collected from six widely separated areas of Southwest Japan and metamorphosed at temperatures from 165 to 655°C show systematic changes with metamorphic temperature that can be classified into four types: low‐grade CM (c. 150–280°C), medium‐grade CM (c. 280–400°C), high‐grade CM (c. 400–650°C), and well‐crystallized graphite (> c. 650°C). The Raman spectra of low‐grade CM exhibit features typical of amorphous carbon, in which several disordered bands (D‐band) appear in the first‐order region. In the Raman spectra of medium‐grade CM, the graphite band (G‐band) can be recognized and several abrupt changes occur in the trends for several band parameters. The observed changes indicate that CM starts to transform from amorphous carbon to crystallized graphite at around 280°C, and this transformation continues until 400°C. The G‐band becomes the most prominent peak at high‐grade CM suggesting that the CM structure is close to that of well‐crystallized graphite. In the highest temperature sample of 655°C, the Raman spectra of CM show a strong G‐band with almost no recognizable D‐band, implying the CM grain is well‐crystallized graphite. In the Raman spectra of low‐ to medium‐grade CM, comparisons of several band parameters with the known metamorphic temperature show inverse correlations between metamorphic temperature and the full width at half maximum (FWHM) of the D1‐ and D2‐bands. These correlations are calibrated as new Raman CM geothermometers, applicable in the range of c. 150–400°C. Details of the methodology for peak decomposition of Raman spectra from the low to medium temperature range are also discussed with the aim of establishing a robust and user‐friendly geothermometer.  相似文献