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31.
以日本结缕草Zenith为材料,通过同源克隆的方法克隆出其磷脂酶D(PLD)基因部分保守序列,序列长399 bp,并通过实时荧光定量PCR检测PLD基因在机械损伤胁迫下随时间变化的表达模式.结果表明,磷脂酶D在胁迫2h内大量表达,随后逐渐降低,在9h已接近于对照水平,说明PLD基因在损伤初期大量参与了应对机械损伤胁迫的防御与修复过程,在损伤后期其作用减弱或被代替;电导率的测定结果表明,细胞膜结构在胁迫初期遭到极大程度的破坏,胁迫9h后膜损伤程度开始减轻.结合PLD基因和电导率的表达模式,推测PLD基因在6h内会激活一系列感受信号及下游信号分子,9h后其相应防御机制发挥作用来减轻胁迫造成的损害. 相似文献
32.
The Japanese archipelago is a biodiversity hotspot with a unique regional climate influenced by the Asian monsoon circulation, surrounding seas, and complex topography. Japan has numerous mountains and islands, which are potentially vulnerable to climate change. This study evaluated the potential impact of climate change on species diversity in Japan, using 25 conifer tree species as a case study. We applied ensemble models based on generalised additive models, artificial neural networks, generalised boostedmodels, and random forests to species’ locality records at 1 km2 resolution. The results indicated a substantial impact, such that 80% of the species may lose over half of their current climatically suitable areas by 2100. The lower altitudinal range limits were projected to shift upwards by 293 m on average, suggesting that alpine/sub-alpine and sub-boreal species may face widespread local extinctions. The impacts on sub-alpine species may be moderated by assisted migration to the northern island where they currently do not occur. However, climatically suitable areas for these species and sub-boreal species that occur on the island overlapped significantly, indicating that assisted migration may entail the risk of introducing biotic competition or interbreeding. Thus, rugged topography and dispersal barriers between islands are likely to amplify the future impacts of climate change in Japan. Limited areas in the central mountain region were identified as potential bioclimatic refugia, which should be conserved as a priority. 相似文献
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34.
抗战时期,桂林的抗战文化运动蓬勃发展,被誉为“文化城”。荟萃桂林的现代作家在中国共产党领导和文协桂林分会的推动下,众志成城,使得桂林的抗战文学创作空前繁荣,创作了一大批思想和艺术较高、影响较大的优秀文学作品,大大地丰富了我国现代文学宝库,在中国新文学史上写下了光辉的一页。 相似文献
35.
Temperature-dependent stock-recruitment model for walleye pollock (Theragra chalcogramma) around northern Japan 总被引:1,自引:0,他引:1
TETSUICHIRO FUNAMOTO 《Fisheries Oceanography》2007,16(6):515-525
Changes in fish year‐class strength have been attributed to year‐to‐year variability in environmental conditions and spawning stock biomass (SSB). In particular, sea temperature has been shown to be linked to fish recruitment. In the present study, I examined the relationship between sea surface temperature (SST), SSB and recruitment for two stocks of walleye pollock (Theragra chalcogramma) around northern Japan [Japanese Pacific stock (JPS) and northern Japan Sea stock (JSS)] using a temperature‐dependent stock‐recruitment model (TDSRM). The recruitment fluctuation of JPS was successfully reproduced by the TDSRM with February and April SSTs, and February SST was a better environmental predictor than April SST. In addition, the JPS recruitment was positively related to February SST and negatively to April SST. The JSS recruitment modeled by the TDSRM incorporating February SST was also consistent with the observation, whereas the relationship between recruitment and February SST was negative, that is the opposite trend to JPS. These findings suggest that SST in February is important as a predictor of recruitment for both stocks, and that higher and lower SSTs in February act favorably on the recruitment of JPS and JSS respectively. Furthermore, Ricker‐type TDSRM was not selected for either of the stocks, suggesting that the strong density‐dependent effect as in the Ricker model does not exist for JPS and JSS. I formulate hypotheses to explain the links between SST and recruitment, and note that these relationships should be considered in any future attempts to understand the recruitment dynamics of JPS and JSS. 相似文献
36.
详细介绍了东京大田农产品批发市场和名古屋批发市场在果菜、水产、花卉方面的交易情况,并对日本批发市场的设置程序和交易原则进行了简要阐述,最后提出发展中国批发市场的几点建议。 相似文献
37.
该文从营养液栽培的发展规模、投资费用、营养液栽培方式等方面介绍了日本营养液栽培的现状、存在的问题及发展方向。在营养液管理方面,已发现单纯依靠检测电导率EC值控制营养液浓度的弊端,提出应针对各种离子的营养液浓度进行管理;各种废液的处理方法和营养液循环利用中去除病原菌和生长阻害物质的方法。分析了各种方法的利弊。最后该文详细介绍了日本营养液栽培的新技术——移动栽培和营养液土耕的基本原理,主要方法和效果。 相似文献
38.
M. Saeki 《Biological conservation》2004,118(5):559-571
We investigated the extent of raccoon dog roadkills, and the factors influencing them, using data from the National Expressways in Japan for 1987-1998. A high rate of raccoon dog roadkills occurred in western Japan, whereas a relatively low rate was typical of the central region and of Hokkaido. Kills on the National Expressways increased as traffic and the length of the road network increased between 1987 and 1998. The relationship between mortality and traffic volume was scale-dependent. The number of roadkills was positively correlated with traffic volume at national level, but negatively correlated with the amount of traffic along sections of an individual major road between exits. There were spring and autumn peaks, and possibly early morning and evening peaks, of mortality. Mortality was higher for roads in a cutting, where the road was closer to water, and where the roadside habitat was broad-leaved woodland. Coniferous forest was negatively associated with roadkills. The total numbers of roadkills on four types of roads (National Expressways, National, Prefectural, and Municipal roads), was estimated to be between 110,000 and 370,000 in 1998. We suggest some preventative measures which might mitigate road casualties (while remaining attentive to human safety). Roadkill data, after controlling for traffic volume, can be useful as a population trend index. Patterns for racoon dogs are compared with those for other species. 相似文献
39.
Hiroyuki Tsuji Hiroyuki Yamamoto Kazuyuki Matsuo Kazuei Usuki 《Soil & Tillage Research》2006,89(2):167-176
A field experiment was conducted from 1983 to 1992 in Tsukuba, Japan to investigate the effects of tillage on soil conditions and crop growth in a light-colored Andosol. Three tillage methods (NT: no-tillage, RT: no-tillage for summer cropping and moldboard plowing for winter cropping, and CT: conventional rotary tillage to a depth of 15 cm) were employed in combination with crop residue application (+R, −R) and fused magnesium phosphate (FMP) fertilization (+P, −P). Under the combination of NT and +R, diurnal variation of soil temperature at a depth of 5 cm was smaller during the summer cropping season and soil temperature in the daytime was lower during the winter cropping season than under CT. Soil inorganic N concentration at a depth of 0–30 cm was +R > −R and NT > RT > CT. The early growth of summer crops was accelerated under NT in comparison with CT, and yields were higher under NT and RT in comparison with CT. On the other hand, winter crop yields were significantly reduced under NT, while they were still higher under RT in comparison with CT. Yields were higher with +R and +P application, respectively, and these effects were more pronounced in winter cropping. The positive effect of FMP fertilization was greater in combination with NT, and that of residue treatment was greater in combination with RT and NT than with CT. In conclusion, the best tillage practice for Andosols on the Kanto Plain is RT, i.e. a combination of NT for summer cropping and CT for winter cropping. The application of NT for winter cropping is not recommended, although the application of phosphate and crop residues could reduce the risk of yield reduction, because of improved soil nutrient status and moderation of diurnal soil temperature. 相似文献
40.
日本检疫性贸易壁垒及我应对措施 总被引:1,自引:0,他引:1
通过对日本检疫性贸易壁垒的分析,我们应根据SPS协议的有关规定,采取必要措施,打破其检疫性贸易壁垒,促进我产品出口。 相似文献