In the previous paper, it was reported that the leaf mass of the two sample plots (A and B) located within the same basin as a power plant, was much smaller not only than the contraol plot (C) located outside of the basin, but also smaller than the values so far available of leaf mass of plantations of the same tree species. As a possible explanation, a smaller production of leaf and/or premature shedding of leaf can be considered. To find out which of them is more important, the leaf-fall was measured for 17 successive months on the three plots. There was hardly any difference in the seasonal pattern of leaf-fall among the three plots, while the amount of leaf-fall-in the plots A and B were much smaller not only than the plot C but also than the values of leaf-fall in plantations of this tree species so far available. The reason for the very small leaf mass of the plots in Owase Baisin may be attributed to a smaller production of leaf, but not to a premature leaf-fall.
Vertical distributions of the numbers of total bacteria and aerobic heterotrophic bacteria, and the flora of the latter in the water and sediment of Lake Motosu-ko were studied in summer, late autumn, and early spring. The numbers of total bacteria and aerobic heterotrophic bacteria in the water were in the order of 10^4 and 10^1-10^2 cells per ml, respectively. The number of aerobic heterotrophic bacteria in the sediment was in the order of 10^4-10^5 cells per ml wet sediment. A total of 609 isolates, 459 from the water and 150 from the sediment, were identified to generic level. Most (84.1%) of the isolates from the water were Gram-negative bacteria. The predominant genera were Flavobacterium (53.9%), Pseudomonas (11.3%, and Moraxella (11.3%). The bacterial flora of the water showed remarkable variations according to water depth, season, and rainfall. On the other hand, most (73.9%) of the isolates from the sediment were Gram-positive bacteria, dominated by Bacillus (55.4%). The bacterial flora of the sediment was rather stable throughout the three seasons.
Survival time of O.latipes exposed to sulphuric acid solutions decreased with a lowering of pH. There was a linear relationship between log survival time and pH value within the range of pH 2.5 to 5.0. The toxicity of strongly dissociating inorganic and organic acids, such as sulphuric, hydrochloric, citric and oxalic acids, was generally low as compared with that of acetic acid. The presence of NaCl, CaCl_2 and MgCl_2 most effectively prolonged the survival of medaka in strongly acidic environments at the concentrations of 100-200 mM, 30 mM and 50mM, respectively. In contrast, the presence of 100-200 mM NaCl reduced survival time at the control pH value (5.5). Oxygen consumption sharply decreased in acidic solutions, but was hardly affected by the presence of NaCl at pH 4.0 except for 150 mM NaCl which is approximately isotonic to fish blood. Free CO_2 more than 30 ppm increased the toxicity of acidic environment. The acidic environment caused coagulation of mucus, but the presence of Ca ions was effective for the suppression of mucous coagulation.
Tephrosia apollinea (DEL.) LINK is a perennial herb of sandy plains and at Jaipur it dominates the vegetation stands throughout the year. The root system is well developed and penetrates to a depth of 3 m or more. This deep root system helps in absorption of moisture from the deeper soil layears. Further, the roots also store the moisture in the cortex which helps the plant in continuing its growth and reproduction at a time when soil moisture is highly deficient.
The percentages of animal materials and crude fiber in the stomachs of the Norway rats indicated that their diet consisted of more variable proportions of those materials in different localities or individuals than that of the roof rats. Thus the Norway rat should be more appropriately called omnivorous, whereas the roof rat is herbivorous or, more precisely, a fruit-and seed-eater, because it selects a large amount of fruits and seeds (51-59%). In the main feeding places in rural areas such as storehouses and storerooms, there generally are present products suitable for diet of roof rat. On the other hand, in the main feeding places in urban areas, i.e.most likely drainage systems connected to kitchens as well as kitchens themselves, there were probably present edible garbage suitable for the diet of the Norway rat, a successful denizen of sewers. Thus they segregated their habitats in each locality. In the forest area in Miyake-jima Is. cohabited by the two species, each species preferred a different diet. Their direct inter specific interactions possibly occurred in a livestock experiment station because the assorted feed represented main diets for both species.
A 50 cm-wide and 3 m-long belt transect situated in a Zizania latifolia zone across the strand of Lake Hinuma was divided into six plots ranging from a dry to a water-logged conditions. In plot V, just below the lowest summer water level, the rhizomes had the least dry matter per quadrat and most, of them were very short, resulting in a maximum shoot/rhizome ratio. The ventilation coefficient and oxygen concentration inside the basal stem were measured and oxygen flux was calculated. The values for the oxygen concentration inside the basal stem correlated well with the soil surface (1 cm deep) redox potential and showed the minimum at plot V, where the development of rhizome was worst. It was surmised that the intensely lowered redox potential of soil at plot V has caused the loss of oxygen through the underground organs. Although the caculated flux at plot V was maximum among the plots, low concentration at the rhizome tip would have suppressed the elongation of rhizome, causing more dry matter to be distributed to the aerial shoots.
The grasslands of the Ishikari coast is occupied by a huge supercolony of Formica yessensis, consisting, of about 45,000 nests. This supercolony skews the habitat preferences of some ants. Thus, some ants are rare or absent in the grasslands (probably as a consequence of avoiding F.yessensis), though they inhabit the forest where F.yessensis is scarce.
While Agrammus agrammus and Hexagrammos otakii coexisted in the observation area, i.e. around a small reef, the former stayed mainly on the algae growing on rock and the latter lived mainly on sandy bottom and was widely distributed on or under rocks and sandy bottom between rocks. Food compositions of these two species living in their main habitats closely resembled each other, but composition of the stomach contents of the same species from different habitats showed considerable difference, even though for a restricted period. For example, in July, 1974,while the food compositions of H.otakii on sandy bottom resemble those of A.agrammus between rocks and algae, the stomach contents of H.otakii on sand differed from those on rocks and the similar situation was observed for A.agrammus.A.agramnuts, H.otakii and other reef fishes distributied around this reef fed on Gammaridea.
Diel activity rhythms of different behaviors in the Indian meal moth, Plodia interpunctella, were studied under various conditions of light-dark cycles at 25℃. The peaks of wandering activity in search of a hibernation site of the larva and of adult eclosion occurred at definite times of the day, but no diel rhythmicity of these behaviors was observed in continuous light or darkness. Pupation occurred at around 8 hr after light-on and at around 4-6 hr after light-off in 16-hr light and 8-hr darkness(16L : 8D) and adult emergence at around 8-10 hr after light-on. The adult eclosion rhythm continued, though not very clearly, after transfer from 16L : 8D to continuous darkness. The calling posture of the female began after light-off and continued during the dark period in 16L : 8D. Moving activities of most male and female adults occurred within 3 hr after light-off in 16L : 8D and the activity rhythm, showed a circadian cycle after transfer to continuous darkness. The peak of oviposition occurred at around light-off in 16L : 8D. The mating began at the first light-off after the eclosion in l6L : 8D.
In the northern slope of Mt.Hachigatake there exists serpentinite area, on which an alpine stony desert plant community has developed extensively. To explain the origin of this palnt community, periglacial slope and debris supply processes were examined.
The proportion of coarse particle ejecta, adhered to twigs and needles of Saghalin-fir (Abies sachalinensis(FR.SCHM.) MAST.), becomes high as same as on the ground at the site near the crater. The thickness of adhered ejecta increased in paralell with the thickness on the ground and it reached an asymptote of 30-40 cm. The amount of needles of Saghalin-fir covered by coarse ejecta at 30-50 cm in depth showed a decrease of 30-50% of dry weight in comparing with that at 2-10 cm depth of ejecta. The decrease seemed to be harmful physical effect, caused by the ejecta adhering on the twigs and needles or Saghalin-fir. The adhered ejecta on the twigs and needles were scattered by the strong wind occurred on september 15 1977. Consequently, by researching on october 12,the amount of ejecta decreased to 1/7 or so against that before the storm.
The utilization of habitat by young pale chub, Zacco platypus (TEMMINCK et SCHLEGEL) was investigated at 21 points in five types of river beds : the shailow pool, the side of shalow pool, the slow rapids, the side of slow rapids, and the submerged plant bed at River Kamo, Kyoto, Japan. In the shallow pool in summer it seemed that the young fishes kept swimming positions stable up to the rather same velocity of running water in the bottom layer as in the surface and the middle layers, and that velocity increased with growth. In autumn only at the points near the shore the density increased in the daytime, in proportion to the differences of water temperature between those points and the centers of the stream, and then the food-intake of one fish was less near the shore of the side of shallow pool than in the shallow pool. These results suggest that the patterns of the distributions or velocity or running water and water temperature among minor habitats in the river bed are important for deciding the utilization of habitat by young pale chub.