Thinning alters crown dynamics and biomass increment within aboveground tissues in young stands of Chamaecyparis obtusa   总被引：1，自引：0，他引：1  

Qingmin Han  Daisuke Kabeya  Satoshi Saito  Masatake G. Araki  Tatsuro Kawasaki  Chiharu Migita  Yukihiro Chiba 《Journal of Forest Research》2014,19(1):184-193

The stand density of a forest affects the vertical distribution of foliage. Understanding the dynamics of this response is important for the study of crown structure and function, carbon-budget estimation, and forest management. We investigated the effect of tree density on the vertical distribution of foliage, branch, and stem growth, and ratio of biomass increment in aboveground tissues; by monitoring all first-order branches of five trees each from thinned and unthinned control stands of 10-year-old Chamaecyparis obtusa for four consecutive years. In the control stand, the foliage crown shifted upward with height growth but the foliage quantity of the whole crown did not increase. In addition, the vertical distribution of leaf mass shifted from lower-crown skewed to upper-crown skewed. In the thinned stand in contrast, the foliage quantity of individual crowns increased two-fold within 4 years, while the vertical distribution of leaf mass remained lower-crown skewed. The two stands had similar production rates, numbers of first-order branches per unit of tree height, and total lengths of first-order branches. However, the mortality rate of first-order branches and self-pruning within a first-order branch were significantly higher in the control stand than in the thinned stand, which resulted in a higher ratio of biomass increment in branch. Thinning induced a higher ratio of biomass increment in foliage and lower in branch. The increased foliage quantity and variation in ratio of biomass increment after thinning stimulated stem growth of residual trees. These results provide information that will be useful when considering thinning regimes and stand management.  相似文献   

Salmonella Infection in Green Anoles (Anolis carolinensis), an Invasive Alien Species on Chichi Island of the Ogasawara Archipelago in Japan     

Daisuke SUMIYAMA  Hidemasa IZUMIYA  Tomoko KANAZAWA  Koichi MURATA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2014,76(3):461-465

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How do visual and auditory cues influence calf stress reactions at weaning?     

Daisuke Kohari  Sachiko Namikawa  Masao Tanaka 《Animal Science Journal》2014,85(3):336-341

We investigated the effects of visual and auditory information related to cow and calf stress responses at weaning. Three weaning conditions were established with physical separation only (PS), physical and visual separation (VS), and physical, visual and auditory separation (VAS). Stress responses such as vocalization and self‐grooming, and changes of three maintenance behaviors (lying, walking and grazing) were recorded for experimental cows and calves in the respective conditions. Comparison of the data revealed that the cow responses differed slightly among groups. However, the peak frequency of vocalization was higher in the PS calves than in those of either VS or VAS. Self‐grooming frequency was significantly different in calves and was high in the order of VAS, VS and PS calves. Furthermore, the percentage of time spent lying down was greater, and that of walking was less, in VAS calves than in either VS or PS calves. These results demonstrate that different information at weaning might strongly affect the stress responses of calves but not those of cows. Relative impacts of different types sensory information on stressors must be considered to plan animal‐friendly weaning.  相似文献   

Growth of the fourspine sculpin <Emphasis Type="Italic">Cottus kazika</Emphasis> in the Gonokawa River,Japan, and effects of water temperature on growth     

Naohiko?TakeshitaEmail author  Itaru?Ikeda  Norio?Onikura  Masato?Nishikawa  Singo?Nagata  Seiichi?Matsui  Seir??Kimura 《Fisheries Science》2005,71(4):784-790

ABSTRACT:   The fourspine sculpin Cottus kazika is indigenous to Japan and found in Honshu except for the waters facing the Seto Inland Sea, and was also found in southern Shikoku and eastern Kyushu. This species has a catadromous lifestyle and migrates as juveniles from the sea to the middle reaches of rivers to grow. The growth pattern of this fish was investigated by a mark-and-recapture method from July 1994 to December 1996, in the Nigorikawa River, a tributary of the Gonokawa River system, Shimane Prefecture. 0-year-old fish of 50–70 mm total length ( TL ) occurred in the study area from June to July, grew to 90–140 mm  TL by the following April, and attained 160–210 mm  TL by December. This fish grew rapidly in September–November and April–July, almost ceasing to grow in July–September. It seems that this stagnant growth phase in summer is a characteristic of the seasonal growth pattern of C. kazika . A rearing experiment indicated that the growth rate of C. kazika was higher at 16–22°C than at 12–14 and 24–26°C. This result supports the field evidence of a stagnant growth phase in summer in the Nigorikawa River.  相似文献   

Effect of shrimp head protein hydrolysates on the state of water and denaturation of fish myofibrils during dehydration   总被引：1，自引：0，他引：1  

Yaowalux?Ruttanapornvareesakul  Misako?Ikeda  Kenji?HaraEmail author  Kazufumi?Osako  Orawan?Kongpun  Yukinori?Nozaki 《Fisheries Science》2005,71(1):220-228

ABSTRACT:   To utilize fisheries waste products as food materials with functional properties, shrimp head protein hydrolysates (SHPH) from three species of shrimp, that is, Northern pink shrimp ( Pandalus eous ), Endeavour shrimp ( Metapenaeus endeavouri ) and Black tiger shrimp ( Penaeus monodon ), were produced by enzymatic hydrolysis using endopeptidase derived from Bacillus subtilis and exopeptidase derived from Aspergillus oryzae at a level of 0.1% (w/w). SHPH were rich in protein (90–91%) and amino acids (71–84%) but little fat (0.01–0.02%). The average molecular weight of SHPH was 300–1400. The effect of 5% SHPH (dry basis) addition on the state of water and denaturation of lizard fish myofibrils (Mf) during the dehydration process was evaluated by the desorption isotherm and the Ca-ATPase activity, and compared with the effect of sodium glutamate (Na-Glu). SHPH decreased the water activity and the Ca-ATPase inactivation, and increased monolayer sorbed water and multilayer sorbed water of Mf, although these effects of SHPH were smaller than those of Na-Glu. These findings suggest that the SHPH suppressed dehydration-induced denaturation of myofibrillar protein by stabilizing the hydrated water surrounding myofibrils.  相似文献   

Do small tributaries function as refuges from floods? A test in a salmonid‐dominated mountainous river     

Itsuro Koizumi  Koh Hasegawa  Daisuke Kishi 《Ecology of Freshwater Fish》2012,21(2):165-167

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Orientation and integration of the classical and molecular genetic maps of chromosome 11 in rice   总被引：8，自引：0，他引：8  

M. L. P. Abenes  R. E. Tabien  S. R. McCouch  R. Ikeda  P. Ronald  G. S. Khush  N. Huang 《Euphytica》1994,76(1-2):81-87

Summary The classical genetic map and molecular map of rice chromosome 11 were oriented to facilitate the use of these maps for genetic studies and rice improvement. Three morphological markers (d-27, z-2, and la) were crossed to a rice breeding line, IRBB21, which has the Xa-21 gene for bacterial blight resistance. Three F₂ populations were analyzed with RFLP markers known to be located on chromosome 11. Segregation analysis of molecular markers and morphological markers was used to construct an RFLP map for each population. The recombination frequency between markers varied from population to population although the marker order on the maps was the same for all three populations. Based on a common set of markers mapped in the three populations, an integrated map was generated consisting of both RFLP and morphological markers. The genetic distance between markers on this map was determined by taking a weighted average of the data from the three populations. The oriented map serves as a bridge to understand the relationship between the classical and molecular linkage maps. Based on this information, the location of several genes on the classical map can be approximated with respect to RFLP markers without having to map them directly.  相似文献   

Nondestructive measurement of cross-sectional shape of a tree trunk     

Akio Koizumi  Keisuke Ikeda  Kei Sawata  Takuro Hirai 《Journal of Wood Science》2011,57(4):276-281

To evaluate windthrow resistance with respect to stem breakage, a nondestructive method for determining the shape of trunk cross sections was developed. In this method, the coordinates of multiple gauge points set on the perimeter of a trunk are calculated by measuring the distances between them. The shape between the gauge points is generated with the use of a profile gauge placed between them. Measurement tests were conducted using profile gauges with lengths of 300 and 900 mm on model specimens with four shape patterns and four different diameters. The accuracy of the estimation was verified by comparing the section modulus calculated for the generated image and for the photograph. The average ratio of section modulus (generated/photo) for all specimens was 0.994, which indicates that the proposed method is highly accurate. The section moduli of hollow trunks can be evaluated using the profile method together with the drill resistance technique on the condition that 26% of the trunk diameter could be drilled without skew.  相似文献   

Bow variation in kiln-dried boxed-heart square timber of sugi (<Emphasis Type="Italic">Cryptomeria japonica</Emphasis>) cultivars     

Kana Yamashita  Yasuhiko Hirakawa  Shuetsu Saito  Hiroshi Nakatani  Motoyoshi Ikeda 《Journal of Wood Science》2011,57(5):363-370

To evaluate the bow variation in boxed-heart square timber of sugi (Cryptomeria japonica), bows from kiln-dried timber for five sugi cultivars with different longitudinal shrinkage trends were compared for two stem heights. Two general trends were observed, depending on the cultivar: (1) either the bow was larger at the lower than at the upper part of the stem, or (2) the bows at the lower and the upper parts of the stem were similar. In timber that had larger bow values, the gradients of longitudinal shrinkage were large across the radius and along the length of the timber. There was a positive relationship between the bow and longitudinal shrinkage. These results suggest that the bow variation between the timbers was caused by a variation in longitudinal shrinkage, which was affected by the microfibril angle. Furthermore, the bow was inversely proportional to the modulus of elasticity, which suggests that timber with a low modulus of elasticity is susceptible to a large bow due to large longitudinal shrinkage.  相似文献   

In vivo antioxidative activity of propolis evaluated by the interaction with vitamins C and E and the level of lipid hydroperoxides in rats   总被引：4，自引：0，他引：4  

Sun F  Hayami S  Haruna S  Ogiri Y  Tanaka K  Yamada Y  Ikeda K  Yamada H  Sugimoto H  Kawai N  Kojo S 《Journal of agricultural and food chemistry》2000,48(5):1462-1465

In vivo antioxidative activity of propolis was evaluated on the basis of ameliorative effects on the oxidative stress induced by vitamin E deficiency in rats. The control group was fed vitamin E-deficient diet, and the propolis group was fed vitamin E-deficient diet supplemented with 1% of propolis for 4 and 8 weeks. Comparisons were made in tissue concentrations of vitamin C, vitamin E, and lipid hydroperoxides between these groups. No significant difference was observed in tissue vitamin E concentration between these groups after both 4 and 8 weeks. After 4 weeks, the plasma vitamin C concentration of the propolis group was significantly higher than that of the control group. After 8 weeks, the tissue concentrations of vitamin C in the kidney, stomach, small intestine, and large intestine of the propolis group were significantly higher than those of the control group. These results suggest that some components of propolis are absorbed to circulate in the blood and behave as a hydrophilic antioxidant that saves vitamin C. The concentration of lipid hydroperoxides in the large intestine of the propolis group was significantly lower than that of the control group after 8 weeks. These results suggest that propolis exerts its antioxidative effect where it is assumed to accumulate, such as on the kidney, where it is excreted, and on the gastrointestinal tract, where propolis influences these tissues even from the outside of the cell.  相似文献