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81.
Chihiro Kayo Seiji Hashimoto Atsunori Numata Masanori Hamada 《Journal of Wood Science》2011,57(3):234-240
We compared the greenhouse gas (GHG) emissions from a log pile (LP) to those from a sand compaction pile (SCP) and from cement
deep mixing (CDM) as measures against soil liquefaction, assuming that forest and waste management scenarios influence the
GHG (CO2, CH4, and N2O) balance of wood. We found little difference between the LP and SCP methods with respect to GHG emissions from fossil fuel
and limestone consumption. However, GHG emissions from the CDM method were seven times higher than emissions from the LP method.
In the GHG balance of wood, when the percentage of CH4 emissions from carbon in underground wood was lower than 3.3%, permanent storage in the log achieved greater reductions in
GHG emissions than using the waste log as fuel in place of coal or heavy oil. In order to obtain reductions in GHG emissions
by replacing SCPs or CDM with LPs, sustainable forest management with reforestation and prevention of CH4 emissions from the underground log are essential. Using reforestation, permanent storage of the log, no CH4 emission from the log, and using logging residues instead of coal, the LP can achieve reductions in GHG emissions of 121
tonnes of CO2 per 100 m2 of improvement area by replacing CDM. 相似文献
82.
A new monocyclic triterpene ester (1) was isolated from the rhizomes of Iris germanica from Turkey. Structure elucidation of compound (1) was carried out by the combined application of HMQC, HMBC, DEPT, COSY and NOESY experiments and named as iristectorone K. 相似文献
83.
Distribution of ectomycorrhizas and ectomycorrhizal fungal inoculum with soil depth in a birch forest 总被引:2,自引:0,他引:2
The distributions of ectomycorrhizas and ectomycorrhizal fungal inoculum with soil depth (0–45 cm) were determined in a 40-year-oldBetula platyphylla var.japonica forest. Mycorrhizal and non-mycorrhizal fine roots were measured in each soil core sample that was collected at soil depths
of 0–5, 5–10, 10–15, 15–20, 20–25, 30–35, and 40–45 cm. The ectomycorrhizas were mainly distributed (>50%) in the top soil
(0–5 cm) of organic forest floor horizons. Below 5 cm the quantity of ectomycorrhizas decreased sharply. The percentage of
fine roots which were ectomycorrhizal gradually declined with the depth of soil. The ectomycorrhizal fungal inoculum was evaluated
by a bioassay method, measuring the lengths of the entire root system and of the ectomycorrhizal roots of birch seedlings
planted in each soil sample. The soil samples were collected from 0–5, 10–15, 20–25, 30–35, and 40–45 cm depths of the soil
profile. Ectomycorrhizal formation on birch seedling roots in the bioassay was high in both the soil depth intervals 0–5 cm
and 10–15 cm, while the amount was lower in the soil depth interval from 20–45 cm. The results of these investigations show
that the amount of the ectomycorrhizas in soil, and the ectomycorrhizal fungal inoculum potential as determined by bioassay,
are not always consistent with each other. 相似文献
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88.
I Takashima N Hashimoto T Watanabe L Rosen 《Nippon juigaku zasshi. The Japanese journal of veterinary science》1989,51(5):947-953
A study was conducted during 1985 and 1986 to evaluate the roles of mosquito species as possible vectors of Japanese encephalitis (JE) virus in Hokkaido. The number of Culex tritaeniorhynchus was very low among the four pig farms where outbreaks of abortion caused by JE virus were observed in swine populations. At one farm near Sapporo, only one Cx. tritaeniorhynchus was found among a total of 510 mosquitoes collected during the survey period from July to October 1985, even when JE virus activity among sentinel pigs was revealed by seroconversion. At another farm in the south, no individuals of this mosquito species were found among 987 mosquitoes collected at the time of the outbreaks of abortion. Cx. pipiens pallens, Anopheles species, Aedes vexans nipponii, and Ae. japonicus were predominant over Cx. tritaeniorhynchus. Cx. tritaeniorhynchus, almost a solve vector species of JE virus in the southern part of Japan, is probably not a vector of the virus in Hokkaido. The collected mosquitoes (2,332 from 1985 and 1,403 from 1986) were processed for virus isolation but no JE virus was isolated. More extensive field studies are necessary to provide further information on the role of mosquito species other than Cx. tritaeniorhynchus in the transmission of JE virus in the northern limits of its range including Hokkaido. 相似文献
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