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51.
52.
Vegetation recovery monitoring and assessment at landslides caused by earthquake in Central Taiwan 总被引:1,自引:0,他引:1
Wen-Tzu Lin Wen-Chieh Chou Chao-Yuan Lin Pi-Hui Huang Jing-Shyan Tsai 《Forest Ecology and Management》2005,210(1-3):55-66
Massive landslides, caused by the catastrophic Chi-Chi earthquake in 1999, occurred at the Jou-Jou Mountain area in the Wu-Chi basin, Taiwan. Multi-temporal satellite images and digital elevation models coupled with GIS were used to process the vegetation index analysis for identifying landslide sites and calculating the vegetation recovery rate (VRR). Topographic information for these areas was extracted. Eight hundred twenty-nine hectares of landslide area was extracted from multi-date NDVI images by combining the image differencing method with the change detection threshold. Over 2 years of monitoring and assessing, the vegetation recovery rate reached 58.93% original vegetation regeneration in the landslide areas. Soil moisture is one of the most important environmental factors for vegetation recovery in the landslide sites. The analyzed results provide very useful information for decision making and policy planning in the landslide area. 相似文献
53.
Two types of forests in Northeast China is divided in this paper,that is,the decidu-ous forests in the northern part and the deciduous-evergreen forests in the eastern part.Both distri-butions of the two types of forests have also been pre sented.Meanwhile,the development and suc-cession as well as components of forests have been studied in detail.in the end,the vertical distribu-tion of the deciduous forests have been shown,in which,the near-temperate cold temperate decidu-ous coniferous forests are distributing in the low elevation area between 450m—600m from the northto the south,the typical siberian cold temperate deciduous coniferous forests are widely distributingfrom 450m—820m in the north to 600m—1050m in the south, the humid cold temperate deciduousconiferous forests can only be found in high elevation area from 820m—1100m in the north to1050m—1380m in the south,the cold temperate deciduous coniferous open forests can seldom ap-pear at the top of a few peaks. 相似文献
54.
Two types of forests in Northeast China is divided in this paper, that is, the deciduous forests in the northern part and
the deciduous—evergreen forests in the eastern part. Both distributions of the two types of forests have also been presented.
Meanwhile, the development and succession as well as components of forests have been studied in detail. In the end, the vertical
distribution of the deciduous forests have been shown, in which, the near—temperate cold temperate deciduous coniferous forests
are distributing in the low elevation area between 450m—600m from the north to the south, the typical Siberian cold temperate
deciduous coniferous forests are widely distributing from 450m–820m in the north to 600m-1050m in the south, the humid cold
temperate deciduous coniferous forests can only be found in high elevation area from 820m–1100m in the north to 1050m–1380m
in the south, the cold temperate deciduous coniferous open forests can seldom appear at the top of a few peaks. 相似文献
55.
The production of galactooligosaccharides (GOSs) by transgalactosylation using beta-galactosidase from Bifidobacterium longum BCRC 15708 was studied. Other than lactose, galactose, and glucose, two types of GOSs, tri- and tetrasaccharides, were formed after beta-galactosidase action on 40% lactose. Trisaccharides were the major type of GOS formed. Generally, an increase of the initial lactose concentration in the reaction mixture resulted in a higher GOS production. A maximum yield of 32.5% (w/w) GOSs could be achieved from 40% lactose solution at 45 degrees C, pH 6.8, when the lactose conversion was 59.4%. The corresponding productivity of GOSs was 13.0 g/(L.h). Transgalactosylation activity of beta-galactosidase from a test organism showed a relatively lower sensitivity toward glucose and galactose than that from other organisms. The addition of 5% or 10% glucose or galactose to the reaction mixture did not significantly (p>0.05) reduce the transgalactosylation reaction of beta-galactosidase. 相似文献
56.
以扬麦16小麦颖果为材料,采用戊二醛-四氧化锇(GA-OsO4)或高锰酸钾固定,并分别用5种染色方法[甲苯胺蓝-O (TBO)、多色性染液、高碘酸–希夫试剂(PAS)、考马斯亮蓝和PAS-TBO]进行半薄切片染色,对超薄切片进行醋酸双氧铀和柠檬酸铅染色,在光学显微镜和透射电镜下观察比较了小麦胚乳细胞结构显示的差异。结果表明,GA-OsO4固定的半薄切片染色效果整体上优于高锰酸钾固定,但是在PAS-TBO复染中,高锰酸钾固定制样效果最好。在超薄切片观察中,GA-OsO4固定制样能较好地保存胚乳细胞超微结构,但对膜性结构显示不够清晰,而高锰酸钾固定制样则能较好地固定细胞的膜性结构,并且能够增强膜结构反差,只是对多糖和蛋白质的固定和显色较差。因此,应根据观察对象来选择适当的固定及染色方法。 相似文献
57.
In the present study, sufu, an oriental fermented product of soybeans, was prepared by ripening the tofu cubes in Aspergillus oryzae fermented rice-soybean koji mash for 16 days at 37 °C. The sufu product was further kept at room temperature for another 30 days. Examining the changes in the sugar content revealed that stachyose, raffinose, and sucrose contents of tofu and rice-soybean koji granules decreased while levels of glucose and fructose increased during the ripening period and after storage. Glucose was the most abundant sugar detected. Four organic acids, including oxalic, lactic, acetic, and citric acid, were detected in the sufu product and koji granules after ripening. Generally, the contents of these organic acid increased as the ripening period was extended. Among them, acetic acid was the most highly detected. 相似文献
58.
Hsiao G Chou PH Shen MY Chou DS Lin CH Sheu JR 《Journal of agricultural and food chemistry》2005,53(20):7734-7740
The aim of this study was to systematically examine the inhibitory mechanisms of C-phycocyanin (C-PC), one of the major phycobiliproteins of Spirulina platensis (a blue-green alga), in platelet activation. In this study, C-PC concentration-dependently (0.5-10 nM) inhibited platelet aggregation stimulated by agonists. C-PC (4 and 8 nM) inhibited intracellular Ca2+ mobilization and thromboxane A2 formation but not phosphoinositide breakdown stimulated by collagen (1 microg/mL) in human platelets. In addition, C-PC (4 and 8 nM) markedly increased levels of cyclic GMP and cyclic GMP-induced vasodilator-stimulated phosphoprotein (VASP) Ser(157) phosphorylation. Rapid phosphorylation of a platelet protein of Mw 47,000 (P47), a marker of protein kinase C activation, was triggered by phorbol-12,13-dibutyrate (150 nM). This phosphorylation was markedly inhibited by C-PC (4 and 8 nM). In addition, C-PC (4 and 8 nM) markedly reduced the electron spin resonance (ESR) signal intensity of hydroxyl radicals in collagen (1 microg/mL)-activated platelets. The present study reports on a novel and very potent (in nanomolar concentrations) antiplatelet agent, C-PC, which is involved in the following inhibitory pathways: (1) C-phycocyanin increases cyclic GMP/VASP Ser157 phosphorylation and subsequently inhibits protein kinase C activity, resulting in inhibition of both P47 phosphorylation and intracellular Ca2+ mobilization, and (2) C-PC may inhibit free radicals (such as hydroxyl radicals) released from activated platelets, which ultimately inhibits platelet aggregation. These results strongly indicate that C-PC appears to represent a novel and potential antiplatelet agent for treatment of arterial thromboembolism. 相似文献
59.
Our aim was to evaluate the inspection of arriving passengers for the illegal transport of animal products through the international airport into Taiwan. Passenger-violation data were retrieved from the Bureau of Animal and Plant Health Inspection and Quarantine (BAPHIQ) in Taiwan. Monte Carlo simulations with 5000 iterations were applied to estimate the predicted violation numbers considering factors such as passenger's nationality/ethnicity, sex, and monthly statistics of violations. The results showed that Chinese-related passengers and passengers from South East Asian countries have a relatively higher potential risk for incurring violations during the period from Christmas to Chinese Lunar New Year. Most monthly estimated violation risks are significantly higher than observed violation risks in 2001 and 2002, except April, July, and August. Due to the low sensitivity of the current detection system (reflected by the higher estimated violation risks and a two-fold detection increase after the implementation of an inspection service using detector dogs), we recommend additional preventive measures be taken. 相似文献
60.
1. The effect of lactic acid marination at 5°C on post mortem changes in breast muscle pectoralis major of spent layer Tsaiya duck was studied.
2. Myofibrils were prepared from 0.1 M and 0.2 M lactic acid marinated muscle and control (non‐marinated samples) sampled at 0, 1, 3, 7 and 14 d post mortem.
3. Changes in myofibril fragmentation index (MFI), myofibrillar proteins and Z‐line structure were examined.
4. Marination of duck breast muscle in lactic acid at 5°C enhanced fragmentation of myofibrils and degradation of myofibrillar proteins and Z‐line structure as compared to control samples.
5. In summary, lactic acid marination at 5°C can accelerate the post mortem degradation of myofibrils in Tsaiya duck breast muscle. 相似文献