Growth and survival of juvenile sporophytes of the kelp <Emphasis Type="Italic">Ecklonia cava</Emphasis> in response to different nitrogen and temperature regimes     

Xu Gao  Hikaru Endo  Michiko Nagaki  Yukio Agatsuma 《Fisheries Science》2016,82(4):623-629

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Comparison of the growth of age-1 Pacific saury <Emphasis Type="Italic">Cololabis saira</Emphasis> in the Western and the Central North Pacific     

Satoshi Suyama  Masayasu Nakagami  Miyako Naya  Yasuhiro Ueno 《Fisheries Science》2012,78(2):277-285

The growth of age-1 Pacific saury Cololabis saira was compared based on an analysis of the body-length frequency distributions, radius of the annual ring (otolith hyaline zones; ROH), and growth patterns in otolith increments. Fish were sampled at various locations between off the Japanese coast (144°E) and in the Central Pacific (160°W) in June and July 2006, and the measurements were compared among the stations ranging over six longitudinal areas, each with a longitudinal area of 10°. The mode of body-length frequency distributions of age-1 fish was larger in fish sampled west of 160°E (size class modes of 32.0–32.5 and 31.5–32.0 cm, respectively, in each 10° longitude area) than in those sampled east of 170°E (28.5–29.0 or 29.0–29.5 cm in 3 areas). The ROH was also larger in the former group (west of 160°E) than in the latter group (east of 170°E), but hatch periods of these two groups and age in days when the hyaline zones form in August or September did not differ based on the analysis of otolith growth increments. The growth difference occurred in the period between when the fish started their northward migration and when the hyaline zone was formed. These results indicate that the habitats of the two groups were separate until at least June or July of their second year of life.  相似文献   

长江三峡花岗岩坡面管流产流特性研究   总被引：19，自引：4，他引：19  

张洪江  史玉虎等 《水土保持学报》2001,15(1):5-8

含有大孔隙的土体 ,如花岗岩风化壳及其上形成的土层水分运动规律并不遵从达西定律 (Darcy L aw) ,大孔隙中运动的水流称为管流 (pipe flow)。在花岗岩地区 ,由于管流的普遍存在 ,从土壤剖面流出的水量远远超出在达西法则定义下流出的水量。为研究土壤水分渗透中非遵从达西定律的土管 (大孔隙 )管流运动规律 ,在位于长江三峡的湖北省秭归县花岗岩坡面进行了管流流量、坡面渗流、地表径流和降雨过程等项目的观测和研究。发现管流在该地区是一种普遍存在的现象 ,管流过程中的水分运动不遵从达西定律 ,其流量在坡面渗流中占的比重约为 10 %～ 30 % ,土管在土壤剖面中所占面积虽然很小 ,但其水分通量远大于相同降雨条件下的土壤剖面水分渗透通量。  相似文献   

Red:far-red light ratio and far-red light integral promote or retard growth and flowering in Eustoma grandiflorum (Raf.) Shinn     

Asuka Yamada  Takahiro TanigawaTakuro Suyama  Takatoshi MatsunoToshihiro Kunitake 《Scientia Horticulturae》2009

Night break treatment was applied to Eustoma grandiflorum ‘Nail Peach Neo’ using light sources with different red (R: 660 ± 30 nm): far-red (FR: 730 ± 30 nm) ratios or FR light intensities in order to investigate growth and flowering responses. Flower initiation and induction were promoted by night break treatment with a low R:FR light source, but was delayed by a high R:FR ratio. The promotion or delay of flower bud formation was accompanied by a decrease or an increase, respectively, in the number of nodes on the main stem at anthesis to the first floret. The difference between date of visible bud with plants under night break treatment and that of the control was approximated with high accuracy by a sigmoid function of the logarithms of R:FR ratio. The threshold R:FR ratio demarcating the promotion and delay of date of visible bud was about 5.3 under the experimental conditions used. The critical R:FR ratios for promotion or delay of visible bud would be about 0.5 and 50.0, respectively. In addition, the time from planting to visible bud was approximated with an exponential function of FR light intensity. The maximum acceleration of date of visible bud by long-day treatment would be 20 days, and the critical FR light intensity would be 2.0 μmol m⁻² s⁻¹. It is concluded that growth and flowering of E. grandiflorum can be regulated by long-day treatment using light sources with different R:FR ratios or FR light intensities.  相似文献   

Effect of forest structure on the spatial variation in soil respiration in a Bornean tropical rainforest   总被引：2，自引：0，他引：2  

Ayumi Katayama  Tomonori Kume  Hikaru Komatsu  Mizue Ohashi  Michiko Nakagawa  Megumi Yamashita  Kyoichi Otsuki  Masakazu Suzuki  Tomo&#x;omi Kumagai 《Agricultural and Forest Meteorology》2009,149(10):1666-1673

This study was undertaken to identify critical and practical factors explaining spatial variations in soil respiration and to estimate stand-scale soil respiration in an aseasonal tropical rainforest on Borneo Island. To this aim, we conducted soil respiration measurements at 25 points in a 40 m × 40 m subplot of a 4 ha study plot between 2002 and 2006, and examined the spatial variation in soil respiration averaged over the 4 years in relation to soil, root, and forest structural factors. In addition, we examined the spatial representativeness of soil respiration measured in the subplot using a specific scaling procedure. Consequently, we found significant positive correlation between the soil respiration and forest structural parameters such as the mean diameter at breast height (DBH), total basal area, and maximum DBH within 6 m of the measurement points. The most important factor was the mean DBH within 6 m of the measurement points, which had a significant linear relationship with soil respiration. Using the derived linear regression and an inventory dataset, we estimated the 4 ha plot-scale soil respiration. The 4 ha plot-scale estimation (6.0 μmol m⁻² s⁻¹) was nearly identical to the subplot-scale measurements (5.7 μmol m⁻² s⁻¹), which were roughly comparable to the nocturnal CO₂ fluxes calculated using the eddy covariance technique. In addition, we discuss characteristics of the stand-scale soil respiration at this site by comparing with those of other forests reported in previous literature in terms of the soil C balance. Soil respiration at our site was noticeably greater, relative to the incident litterfall amount, than soil respiration in other tropical and temperate forests probably owing to the larger total belowground C allocation by emergent trees. Overall, this study suggests the arrangement of emergent trees with larger DBH and their belowground C allocation could be primary factors controlling spatial variations in soil respiration in the tropical rainforest.  相似文献   

Anti-inflammatory constituents from Tabebuia avellanedae     

Maorong Suo  Hasegawa Isao  Hikaru KatoFumihide Takano  Tomihisa Ohta 《Fitoterapia》2012

Five novel compounds were isolated from the water extract of Tabebuia avellanedae, and their structures were established by analysis of NMR spectroscopy and mass spectrometry. Compounds 1–5 at 25 μM showed strong inhibitory activity on the inflammatory cytokine, tumor-necrosis factor-α and interleukin-1β production in cultured human myeloma THP-1 cells co-stimulated with lipopolysaccharide without any significant cytotoxicity, and their anti-allergic and antioxidant activities were evaluated.  相似文献   

Soluble starch synthase I effects differences in amylopectin structure between indica and japonica rice varieties     

Takemoto-Kuno Y  Suzuki K  Nakamura S  Satoh H  Ohtsubo K 《Journal of agricultural and food chemistry》2006,54(24):9234-9240

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晋西不同林地状况对糙率系数n值影响的研究   总被引：13，自引：0，他引：13       下载免费PDF全文

张洪江  北原曜  远藤泰造  解明曙 《水土保持通报》1995,15(2):10-21

在野外小区径流实验基础上，通过经转换的曼宁公式，对不同坡地地表的糙率系数ｎ值进行了定量研究，结果表明，林地上的糙率系数ｎ值与林地地表残存的枯落物量和生长的草量呈正相关关系，不同土地利用现状的地表糙率系数ｎ值按由低到高的顺序排列，依次为土质路面，农耕地、核桃果园、人工剌槐林地、灌木林和人工油松林地，该还探讨了糙率系数ｎ值与地表水分渗透量的关系。初步结果表明：糙率系数ｎ值较大的地表其水分渗透能力地较  相似文献   

Iron speciation in iron-rich wood by Mössbauer spectroscopy     

Shigeru Yamauchi  Yoichi Sakai  Hikaru Aimi 《Journal of Wood Science》2011,57(6):549-552

Several iron-rich wood samples were investigated using Mössbauer spectroscopy to obtain information on the chemical state of the iron species contained in them. The Mössbauer spectrum of Japanese cedar (Cryptomeria japonica D. Don) wood containing iron species that originated from rusted nails exhibited a symmetrical doublet from a high-spin Fe(III) species, which is expected to be γ-FeOOH (lepidocrocite). Mössbauer absorption attributable to high-spin Fe(III) was observed for ancient buried wood samples of both Japanese cedar and Japanese cypress (Chamaecyparis obtusa Endlicher). Moreover, Mössbauer measurement indicated that the ancient buried Japanese cedar also possessed high-spin Fe(II) species.  相似文献   

Application timing of asulam for torpedograss (Panicum repens L.) control in sugarcane in Okinawa island     

Mohammad Amzad Hossain  Hitoshi Kuramochi  Yukio Ishimine  Hikaru Akamine 《Weed Biology and Management》2001,1(2):108-114

Field and glasshouse experiments were conducted from 1995 through 1996 to evaluate application timing of asulam (methyl sulfanilylcarbamate) for torpedograss (Panicum repens L.) control in relation to plant age in sugarcane. Above‐ground shoots of torpedograss were completely controlled with asulam at 2–4 kg active ingredient (a.i.) ha^?1 applied 60 or 80 days after planting (DAP) in artificially infested pots. But some newly developed rhizome buds survived after asulam application resulting in 1–25 and 76–100% or more regrowth in 60 and 80 DAP‐applied pots, respectively. Whereas the herbicide at 2–4 kg a.i. ha^?1 applied within 60 DAP completely controlled above‐ground shoots, applied 80 DAP at 2 kg a.i. ha^?1 it did not completely control the weed in the artificially infested field. Regrowth levels were 1–25 and 76–100% or more in 60 and 80 DAP‐applied plots, respectively. Asulam at 2–3 kg a.i. ha^?1 applied 20, 40, 60 or 80 DAP in a naturally infested field completely controlled above‐ground shoots and regrowth levels were 76–100 or more, 51–75, 1–25 and 26–50% in these same DAP applied plots, respectively. The herbicide applied at 4 kg a.i. ha^?1 caused chlorosis on younger sugarcane leaves (one‐leaf stage), but when applied at 2–3 kg a.i. ha^?1, no injury symptoms were shown. The herbicide at 2–4 kg a.i. ha^?1 applied within 60 DAP resulted in remarkably higher yield and shoot biomass of sugarcane than that applied 80 DAP. This study suggested that asulam at 2–3 kg a.i. ha^?1 should be applied 60 days after planting for the maximum control of torpedograss regrowth and better yield of sugarcane. This study also indicated that torpedograss cannot be completely controlled with a single application of asulam in a naturally infested field because of rhizome fragmentation by cross plowing and distribution of rhizomes into different soil layers that require different times to emerge. The shoots emerging after asulam application could not be controlled. Another study is required to determine the interval between sequential applications of asulam for better control of torpedograss in a naturally infested field.  相似文献