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71.
Cycling of soil carbon in the first year after a clear-felling was compared with that before the felling in a Japanese red
pine forest in Hiroshima Prefecture, west Japan. The daily mean temperature at the soil surface in summer was increased after
the felling in comparison to that before felling, and the water content of both the A0 layer and the surface mineral soil was decreased due to the loss of the forest canopy. The rate of weight loss of the A0 layer was reduced after felling. However, accumulation of the A0 layer rapidly decreased because of the lack of litter supply to the forest floor. Low soil respiration after felling was
mainly caused by the cessation of root respiration. Analysis of annual soil carbon cycling was then conducted using a compartment
model. The relative decomposition rate of the A0 layer decreased whereas that of humus and dead roots in mineral soil increased to some extent after felling. The accumulation
of carbon in mineral soil, however, increased slightly due to the supply of humus from roots killed by the felling. 相似文献
72.
Five species including two new species,Araucarioxylon kiiense Ogura,Taxodioxylon albertense (Penhal.) Shimakura,Cupressinoxylon cryptomerioides Stopes,Xenoxylon watarianum sp. nov. andCedroxylon shimakurae sp. nov., were described from the Upper Cretaceous (Late Turonian-Santonian) of southern Saghalien.
Consecutive number from the previous paper (Nishida and Nishida, 1985).
Contributions from the Laboratory of Phylogenetic Botany, Chiba University No. 100. Supported by a Grant-in-Aid for Scientific
Research from the Ministry of Education, Science and Culture No. 59540441. 相似文献
73.
74.
Effect of polyamines on synthesis and degradation of guanosine 5'-diphosphate 3'-diphosphate 总被引:2,自引:0,他引:2
K Igarashi K Mitsui M Kubota M Shirakuma R Ohnishi S Hirose 《Biochimica et biophysica acta》1983,755(3):326-331
The effect of polyamines on the in vitro and in vivo synthesis and degradation on guanosine 5'-diphosphate 3'-diphosphate (ppGpp) has been studied in Escherichia coli. The presence of 2 mM spermidine lowered the optimal Mg2+ concentration for ppGpp formation from 17 mM to 11 mM. The formation of ppGpp in the presence of 2 mM spermidine and 11 mM Mg2+ was about 15% greater than that in the presence of 17 mM Mg2+. At a concentration of less than 11 mM Mg2+, spermidine was found to stimulate ppGpp formation greatly. Putrescine did not cause any effect. When a polyamine-requiring mutant of E. coli (EWH319) was starved for an amino acid by the addition of valine, spermidine stimulated ppGpp formation. The degradation of ppGpp was not influenced significantly by polyamines. 相似文献
75.
Mitochondria were isolated from mesophyll protoplasts and bundlesheath protoplasts or strands which were obtained by enzymaticdigestion of six C4 species: Zea mays, Sorghum bicolor, Panicummiliaceum, Panicum capillare, Panicum maximum and Chloris gayana,representative of three C4 types. Photorespiratory glycine oxidationand related enzyme activities of mesophyll and bundle sheathmitochondria were compared. Mesophyll mitochondria showed good P/O ratios with malate andsuccinate as substrate but lacked the ability to oxidize glycine.On the other hand, mitochondria isolated from bundle sheathprotoplasts of P. miliaceum and bundle sheath strands of Z.mays possessed glycine oxidation activity similar to that ofmitochondria from C3 plant leaves. The two enzymes involvedin glycine metabolism in mitochondria, serine hydroxymethyltransferaseand glycine decarboxylase, were also assayed in the mitochondriaof the two cell types. The activities of the two enzymes inbundle sheath mitochondria were in the range found in C3 mitochondria.In contrast, the activities in mesophyll mitochondria were eithernot detectable or far lower than those in bundle sheath mitochondriaand ascribed to contaminating bundle sheath mitochondria. The present results indicate the deficiency of a complete glycineoxidation system in mesophyll mitochondria and also a differentiationbetween mesophyll and bundle sheath cells of C4 plants withrespect to the photorespiratory activities of the mitochondria. (Received June 8, 1983; Accepted August 29, 1983) 相似文献
76.
77.
Makoto Hayashi Kazuko Fukushima Akihide Kitamura 《Chemistry and physics of lipids》1983,33(3):233-239
Krafft points of diacylglycerophosphocholines (PC) were measured in alkanes-cyclohexane solutions by differential scanning calorimetry, and it was found that they were regularly increased following the increase in alkane content in the solutions and the chain length of the alkanes. From these results it was deduced that the mixing of PC with alkanes occurred in the gel state of the PC, but not in micelles at higher temperatures above the Krafft points. where micellar solutions are provided. The penetration of alkanes into gel state PC was found to be dominated by Langmuir type interaction, and the affinity of alkanes increases with increasing in chain lengths. Above the Krafft points, the micelle formation was confirmed by using the fluorescence probe technique. 相似文献
78.
Solaniol, a Toxic Metabolite of Fusarium solani 总被引:7,自引:6,他引:1
Kenji Ishii Kosei Sakai Yoshio Ueno Hiroshi Tsunoda Makoto Enomoto 《Applied microbiology》1971,22(4):718-720
Fusarium solani M-1-1 isolated from moldy bean hulls produces T-2 toxin, diacetoxyscirpenol, and a new toxic trichothecene, solaniol, in Czapek-Dox-peptone medium. 相似文献
79.
Makoto Nagoshi 《Population Ecology》1966,8(1):20-36
- In order to get the knowledge on the age composition of “isaza” population in Lake Biwa and the effect of population density on growth, monthly distribution of mean body length and mean body weight has been analyzed on the basis of monthly haul by “isazabiki” trawl during 1949 to 1953 and also 1960 to 1965.
- There is no apparent sex difference in the growth in the first and second years of life.
- “Isaza” population is composed of two age groups, age 0 and 1 groups (1+fish), the latter occupying by far the greater part in commercial catch.
- During the growth season fishes of both ages feed mainly on zooplankton, though in winter frequently take chironomid larvae, gammaridae and others in volume.
- The growth season falls in the period from April to October in both age groups.
- A considerable yearly variation occurring in growth is in close connection with the fluctuation of population density of all ages.
- The influence affected by the density of age 1 group is larger than that by age 0 group.
80.
Makoto Endo 《Ichthyological Research》1989,36(3):346-349
Glomerular vasculature was investigated in the carpCyprinus carpio, the scorpionfishSebastiscus marmoratus, and the marine catfishPlotosus lineatus with the resin-replica method. An afferent arteriole was connected with a glomerulus in every fish. It was slender in the
carp, whereas the scorpionfish and marine catfish possessed thick afferent arterioles. The glomerular capillaries were sinusoidal.
The divergences, convergences, and windings of these capillaries were not well developed in any of the fish. The glomerular
capillaries converged into an efferent arteriole in the carp and scorpionfish. In the marine catfish, on the other hand, most
of the glomeruli had two efferent arterioles. 相似文献