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141.
142.
The use of heterospecific scent marks by the sweat bee <Emphasis Type="Italic">Halictus aerarius</Emphasis> 总被引:2,自引:1,他引:1
To forage effectively amongst flowers, some bee species utilize olfactory cues left by previous visitors in addition to direct
assessment of visual cues to identify rewarding flowers. This ability can be more advantageous if the bees can recognize and
use scent marks left by heterospecifics, not just marks left by members of their own species. We conducted field experiments
to investigate whether the sweat bee Halictus aerarius avoids visiting flowers of trailing water willow Justicia procumbens emptied by other bee species. We found that H. aerarius rejected the flowers visited by both heterospecifics and conspecifics. They also rejected visited flowers artificially replenished
with nectar. Our results demonstrate that social bees outside the Apidae can detect marks left on flowers by heterospecifics
but that (on this plant species) they are unable to discriminate against flowers by directly detecting nectar volume. H. aerarius exhibited different rejection rates according to the identity of the previous bee species. We suggest that the frequency
of rejection responses may depend on the amount of chemical substances left by the previous bee. In general, the use of scent
marks left by previous visitors is almost certainly advantageous, enabling foragers to avoid flowers with depleted nectar
levels and thereby improving their foraging efficiency. 相似文献
143.
Jun Yamamoto Miyuki Hirose Tetsuya Ohtani Katashi Sugimoto Kazue Hirase Nobuo Shimamoto Tsuyoshi Shimura Natsumi Honda Yasuzumi Fujimori Tohru Mukai 《Marine Biology》2008,153(3):311-317
The fate of the giant jellyfish Nemopilema nomurai after death was examined in the southwest Sea of Japan. The density of dead jellyfish was greater than that of live animals.
The dead animals are heavier than the Japan Sea Proper Water which occurs deeper than 200 m, suggesting that dead jellyfish
sink to the sea floor. The sea floor survey, conducted with a towed video tape recorder (VTR) monitoring system between mid
September and mid October, observed a total of 138 jellyfish during 28 of 29 operations. The density of carrion ranged between
0.2 and 5.1 individuals/1,000 m2 (mean ± SE = 1.1 ± 0.2). Ophiuroids occurred abundantly at 23 jellyfish carcasses and a sea anemone was observed attached
to five carcasses. The VTR surveys confirmed that carrion sinks to the sea floor not only during the winter, the normal end
of life for medusae, but also during the fall. A trap survey baited with medusae was also employed, and four different species
were sampled with the traps: the snow crab (Chionoecetes opilio), a shrimp (Pandalopsis japonica), the ivory shell (Buccinum striatissimum) and an ophiuroid (Ophiura sarsii). Much of the trap bait remained (49–68% weight-mean = 60.3%) during the 23 h soak-time, and the reduction in weight was
greater than that observed by bacterial decomposition, suggesting benthic animals consume dead organisms. The present study
indicates that dead N. nomurai sink to the sea floor continuously and were subsequently consumed by benthic scavengers. 相似文献
144.
A simple technology for phosphate (P i ) recovery has been developed using a bifunctional adsorption–aggregation agent. The bifunctional agent was prepared by soaking calcium silicates in hydrochloric acid solution. Importantly, recyclable calcium silicates were available almost free of charge from the cement industry and also from the steel industry. The acid treatment was essential not only for enhancing the ability of calcium silicates to remove P i from aqueous solution but also for enabling the high settleability of removed P i . On-site experiments using a mobile plant showed that approximately 80% P i could be recovered from anaerobic sludge digestion liquor at a wastewater treatment plant. This technology has the potential to offer a simple, compact service for recycling P i from wastewater to farmland in rural areas. 相似文献
145.
Thomas Dominguez Johanna Aurell Brian Gullett Robert Eninger Dirk Yamamoto 《Journal of Material Cycles and Waste Management》2018,20(2):902-913
Emissions from open burning of military food waste and ration packaging compositions were characterized in response to health concerns from open burning disposal of waste, such as at military forward operating bases. Emissions from current and prototype Meals, Ready-to-Eat (MREs), and material options for their associated fiberboard packaging were quantified to assess contributions of the individual components. MREs account for 67–100% of the particulate matter (PM), volatile organic compounds (VOCs), polycyclic aromatic hydrocarbons (PAHs), and polychlorinated dibenzo-p-dioxins and -furans (PCDDs/PCDFs) emissions when burned in unison with the current fiberboard container and liner. The majority of the particles emitted from these burns are of median diameter 2.5 µm (PM2.5). Metal emission factors were similar regardless of waste composition. Measurements of VOCs and PAHs indicate that targeted replacement of MRE components may be more effective in reducing emissions than variation of fiberboard-packaging types. Despite MRE composition variation, equivalent emission factors for PM, PAH, VOC, and PCDD/PCDF were seen. Similarly, for fiberboard packaging, composition variations exhibited essentially equivalent PM, PAH, VOC, and PCDD/PCDF emission factors amongst themselves. This study demonstrated a composition-specific analysis of waste burn emissions, assessing the impact of waste component substitution using military rations. 相似文献
146.
Takashi Yamamoto Akiko Kida Yukio Noma Atsushi Terazono Shin-ichi Sakai 《Journal of Material Cycles and Waste Management》2018,20(1):214-222
Appropriate treatment of asbestos waste is a significant problem. In Japan, inertization of asbestos-containing waste by novel techniques approved by the Ministry of the Environment is now promoted. A quantitative method of testing with high sensitivity to the asbestos levels present in the inertization products is required for the approval process, but many testing methods are only qualitative. Thus, we have developed an evaluation method for asbestos in inertized products, consisting of the extraction of fibers from inertized products and determination of fiber number concentration by transmission electron microscopy. We adopted this testing method to evaluate thermally treated asbestos. It was found that fiber number concentrations of thermally treated asbestos decreased with increased treatment temperature, and were below the environmental level (102 Mf/g) at more than 1000 °C for chrysotile and crocidolite and more than 1400 °C for amosite and other amphibole forms of asbestos. 相似文献
147.
Koki Sato Kazuya Yamamoto Jun-ichi Kadokawa 《Journal of Polymers and the Environment》2018,26(9):3540-3549
In this study, we investigated the preparation of cationic/anionic chitin nanofiber (CNF) composite materials by electrostatic interaction. An aqueous dispersion of amidinium CNF was prepared by a top-down approach, and a maleylated CNF film was obtained by a bottom-up approach from a chitin ion gel in an ionic liquid with subsequent maleylation on the CNFs. The resulting film was dispersed in ammonia (aq), which was then mixed with the aqueous cationic CNF dispersion to give the composite film. The composition of the two CNFs was evaluated by scanning electron microscopy and X-ray diffraction measurements. Tensile testing results indicated that the mechanical properties of the composites were enhanced with increasing degrees of substitution of the cationic and anionic groups on CNFs, and also when the molar ratio of these groups approached 1:1. The dissociation of the two kinds of CNFs by alkaline treatment of the composite film was achieved, suggesting the presence of an electrostatic interaction among the interactions between them. 相似文献
148.
Ribeiro Bruno Yamashiro Yuta Goto Katsuaki Tomiyama Jun Yamamoto Takashi Yamashiki Yosuke 《Journal of Material Cycles and Waste Management》2023,25(4):2381-2389
Journal of Material Cycles and Waste Management - Shotcrete is a sprayed concrete placed on steep slopes that have been widely used because it can prevent surface weathering and erosion, and in... 相似文献
149.
Masumi Koriyama Yuichi Hayami Akane Koga Koichi Yamamoto Alim Isnasetyo Takaharu Hamada Kenji Yoshino Toshiya Katano Soichi Yamaguchi 《Environmental monitoring and assessment》2013,185(8):6831-6846
To investigate seasonal variations of nutrient distribution in the mudflat–shallow water system, we conducted field surveys once a month from August 2007 to July 2008 in the inner area of Ariake Bay (IAB), Japan. The NH4 +–N concentration of the water column increased in autumn because of the high NH4 + release from the sediments, ranging from 850 to 3,001 μmol?m?2?day?1. The NO3 ?–N concentration was maximal in January, which was thought to be caused by NO3 ? release from the oxic sediments and by NO3 ? regeneration due to water column nitrification. The PO4 3?–P concentration of the water column was high in summer–autumn due to the high PO4 3? release from the reduced sediments, ranging from 22 to 164 μmol?m?2?day?1. We estimated the total amounts of DIN and PO4 3?–P release (R DIN and $ {R_{{\mathrm{P}{{\mathrm{O}}_4}}}} $ , respectively) from the muddy sediment area of the IAB. In summer–autumn, R DIN and $ {R_{{\mathrm{P}{{\mathrm{O}}_4}}}} $ corresponded to about 47.7 % of DIN input and about 116.6 % of PO4 3?–P input from the river, respectively. Thus, we concluded that the muddy sediments were an important source of nutrients for the water column of the IAB during summer–autumn. In addition, we found that phosphorus necessary for the growth of Porphyra (Porphyra yezoensis, Rhodophyceae) would be insufficient in the water column when phosphorus during the Porphyra aquaculture period is supplied only from the river. Therefore, the phosphorus release from the muddy sediments was thought to play an important role in the sustainable production of Porphyra in Ariake Bay. 相似文献
150.
Asano R Kubori K Ozutsumi Y Yamamoto N Otrawa K Nakai Y 《Journal of environmental science and health. Part. B》2011,46(2):122-127
Livestock manure is suitable for use as a composting material. However, various intestinal microbes, such as Escherichia coli, are significant components of such manures. Thus, it is desirable that the level of intestinal microbes, and particularly opportunistic pathogens, in compost is inspected and counted regularly. The sensitivity and specificity of detection of E. coli in compost have been improved by selective cultivation followed by colony polymerase chain reaction (PCR) using the ECO primer. Indeed, the sensitivity of this method is higher than that of DNA extraction from compost and PCR. In this study, changes in numbers of E. coli present in a field-scale composting process over time was assessed using selective cultivation and colony PCR. Numbers of ECO-positive colonies after 24 h decreased, with a concomitant rise in compost temperature. ECO-positive colonies were not detected from 33 to 48 h. However, ECO-positive colony numbers increased beginning on day 4 and continuing until day 42. Thus, it seems likely that the high temperatures reached during the composting process did not affect E. coli numbers in the final compost. Additionally, selective cultivation followed by colony PCR using specific primers is an appropriate method of determining levels of cultivable pathogens in composted materials. 相似文献