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91.
以纪念女性为主的园林是中国历史园林的特殊类型,理清其营建的动因和经验,是传承中国园林文化的重要补充。纪念唐代女诗人薛涛的望江楼公园,其兴建、发展、造景等方面与薛涛的人生经历、个性品行紧密结合。基于历史文献梳理和园林空间分析,剖析了望江楼公园的发展变迁历程,归纳了针对薛涛的园林景观的纪念性造景手法,从遗迹、植物、建筑、活动等方面分析了女诗人薛涛与望江楼公园之间相辅相成的关系。 相似文献
92.
Hidenori Tozuka Michikazu Ota Hisayoshi Kofujita Kouetsu Takahashi 《Journal of Wood Science》2005,51(1):48-59
The protected structure of -oxoacteoside (tomentoside A), 2-oxo-2-(3,4-dihydroxyphenyl)ethyl 3-O-(2,3,4-tri-O-acetyl--l-rhamnopyranosyl)-4-O-caffeoyl--d-glucopyranoside 14 was synthesized in 14% overall yield in 11 steps, starting from d-glucose for biological and medicinal studies of phenylpropanoid glycosides. The first step was the preparation of a 3-O-rhamnopyranosyl disaccharide sugar core 2 from a suitably protected rhamnosyl trichloroacetimidate 10 and glucose derivative (diacetone-d-glucose 1) in 71% yield. To the glucose moiety of this sugar core, several protection/deprotection procedures were performed sequentially to obtain a fully acetylated sugar core 7 with a 4-OH group on the glucose moiety, in 57% yield in five steps. Thereafter, to the 4-OH group of the glucose moiety, selective 4-O-caffeoylation was achieved by proton-transfer esterification with 3,4-di-O-allylcaffeic acid 16 to give the caffeoyl disaccharide 11 in 97% yield. Then, it was converted to trichloroacetimidate 13 for a glycosylation donor in 90% in two steps. Finally, anomeric glycosylation was conducted with 2-oxo-2-(3,4-di-allyloxyphenyl)ethyl alcohol 19 with catalytic amounts of BF3·Et2O to give 2-oxo-2-(3,4-di-allyloxyphenyl)ethyl 2,6-di-O-acetyl-3-O-(2,3,4-tri-O-acetyl--l-rhamnopyranosyl)-4-O-(3,4-di-allyloxycaffeoyl)--d-glucopyranoside 14 in 60% yield. Deprotected intermediates of compounds 2, 11, 14, and 19 which were obtained in high yield would be useful for biological and medicinal studies of phenylpropanoid glycosides.Part of this study was presented at the 52nd Annual Meeting of the Japan Wood Research Society, Gifu, April, 2002 相似文献
93.
对20年生马尾松人工林生物量的研究表明,全林生物量38.42吨/公顷,间伐后年生产量6.49吨/公顷林木根量5.73吨/公顷,相对生长率19.0%,净同化率0.253公斤/米~2·年,生产力水平偏低。林分抚育间伐后,林木的生物生产力得到提高。建立了林木各器官干重与直径树高的8个相关方程,相关系数均在0.92以上。通过叶面积及其生长函数分析,林分密度过高,生长速率降低,建议及时合理地调节林分密度。 相似文献
94.
Salt distribution in response to optical stratification porosity and relative windspeed in a coastal forest in Niigata, Japan 总被引:3,自引:0,他引:3
Wind velocity, vertical stand structure and seasalt distribution were measured at various heights inside a plantation of coastal pine forest, with thinning and unthinning, to assess whether any relationships exist between the wind profile, stand structure and seasalt distribution in the coastal pine forest. The vertical stand structure, i.e., optical stratification porosity (OSP), which is defined as vertical distribution of the proportion of sky hemisphere not obscured by tree elements inside a forest stand, was determined for each height by computer analysis of digital images taken with a hemispherical lens. The distribution of OSP in the coastal forest follows the Lambert-Beer's law with absorbency coefficient (). The relative windspeed within canopy can be described using the exponential form with the attenuation coefficient (). The sea-salt was collected using salt gauze (a surgical dressing of loosely woven cotton) both inside and outside the coastal forest, and the distribution of sea-salt within canopy was also in accordance with an exponential function. The relationships among windspeed, OSP and sea-salt indicate that the distributions of both sea-salt and windspeed within canopy were very closely correlated with the distribution of OSP. A linear relationship between OSP and sea-salt has been found. Additionally, linear regression between coefficients and has been obtained as well. Based on these relationships between OSP, wind and sea-salt in the coastal forest, the sea-salt distribution and wind profile within the canopy of the coastal forest can be predicted according to OSP. These results may therefore be useful in analyzing the effects of sea-salt on vegetation and evaluating the filter functions of coastal forests.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
95.
96.
A survey of forestry practices and attitudes was undertaken in four communities in Leyte, the Philippines, to improve understanding
of the social and economic factors affecting small-scale forestry development. The survey had three main data collection activities
— initial focus group discussions (FGDs), household interviews, and reporting and validation FGDs. A team of enumerators was
selected for household interviews which consisted of both males and females, to avoid potential problems of unwillingness
of people to talk with those of the opposite gender. The interviewers were also required to be able to speak local dialects
(Cebuano and Waray Waray), the survey questionnaires being administered in these dialects. Various methods were used to gain
the support and assistance of local government units and barangay captains. Some difficulty was experienced by the survey
team in the first community due to barangay elections at the time of the survey, and the requirement by the University of
Queensland Ethics Committee that respondents sign a consent form. This requirement was found to be not culturally appropriate
for the Leyte smallholder communities. Offering goods at the end of the interview was found to be of limited value for encouraging
participation in the survey. Provision of food and drinks were found to encourage FGD participants to express their views,
but too much alcohol had a negative effect. The importance of providing comprehensive feedback to respondents and involving
them and other stakeholders in development of policy recommendations was apparent. These survey experiences provide valuable
insights which are not generally available in textbooks on sample surveys, and provide lessons for planning and conducting
smallholder community survey into natural resource management issues. 相似文献
97.
A study was conducted to assess the role and effectiveness of community organisers in supporting the development of people’s
organisations in achieving community-based forest management objectives in Leyte Province Philippines. Community organisers
were found to be effective in forming people’s organisations (POs), motivating people to participate in voluntary activities
organised by POs and encouraging cohesiveness among PO members. Community organisers manage to raise the level of environmental
awareness and knowledge of members of people’s organisations, develop leadership interest and skills, create various livelihood
opportunities and provide direction and facilitate the establishment of large tree plantations. However, the short duration
of community organisers’ contracts (typically two years) is insufficient to establish mature and cohesive POs prepared to
assume management on their own, including the management of tree plantations. Further, lack of training and funding support,
low wages, delayed payment of salaries and limited time to work with people’s organisations, as well as the pressure to produce
tangible outputs such the establishment of large tree plantations, prevents them from placing greater emphasis on the development
and empowerment of the people. 相似文献
98.
Hans Pretzsch 《Forstwissenschaftliches Centralblatt》2003,122(4):231-249
Zusammenfassung: Die Nachhaltigkeit richtete sich in der Gründerzeit der planmäßigen Forstwirtschaft auf die Holzproduktion (v. Carlowitz 1713, Cotta 1828, Hartig 1804, Hundeshagen 1826). In der Folgezeit wurde ein zunehmend breiteres Spektrum von Leistungen des Waldes in die Planung mit einbezogen (v. Hagen, 1867; Dieterich, 1957). Das heutige Verständnis von multifunktionaler Forstwirtschaft spiegelt sich in den sechs gesamteuropäischen Kriterien und Indikatoren für nachhaltige Forstwirtschaft wider (McPfe, 2000). Vorliegender Aufsatz umreißt, wie diese gesamteuropäischen Kriterien und Indikatoren für den Nachweis und die strategische Planung von Nachhaltigkeit auf Forstbetriebsebene eingesetzt werden können und was die Waldwachstumsforschung dazu beitragen kann. An einer Reihe von Beispielen wird ausgeführt, dass die Forstwirtschaft über eine solide Datenbasis für die Ableitung von Nachhaltigkeitskriterien und Indikatoren verfügt. Diese kann für das Monitoring der Waldentwicklung genutzt werden. Gestalterische Kraft entwickeln die Kriterien und Indikatoren aber erst, wenn sie auch in die strategische Planung einfließen. Für die strategische Planung stehen der Forstwirtschaft Wuchsmodelle, Betriebssimulatoren und Entscheidungsstützungssysteme zur Verfügung. Sofern diese die genannten Kriterien und Indikatoren berücksichtigen, ermöglichen sie Szenariorechungen auf Betriebsebene und eine umfassende Bewertung von Handlungsalternativen. Konzepte und Werkzeuge für den Übergang zu einer multifunktionalen strategischen Nachhaltsplanung sind weit entwickelt (v. Gadow 2003, Hanewinkel 2001, Pretzsch et al. 1998, Spellmann et al. 2001); ihre Einführung in die Forstplanung könnte einen beträchtlichen Innovationsstau beseitigen. 相似文献
99.
Takeshi Katayama Jyoji Tsutsui Kazuo Tsueda Takao Miki Yasuhiro Yamada Murao Sogo 《Journal of Wood Science》2000,46(6):458-465
When (±)--oxo-guaiacylglycerol--(vanillic acid) ether (1) is degraded byFusarium solani M-13-1, the-ketone is initially reduced to giveerythro andthreo guaiacylglycerol--(vanillic acid) ethers (2), arylglycerol--aryl ethers, both of which are enantiomerically pure. The absolute configuration in each2 was determined by Mosher's method; the products were converted to,-di-(R)--methoxy--trifluoromethylphenylacetates (MTPA esters) (3) oferythro (-)- andthreo (+)-veratrylglycerol--(methyl vanillate) ethers (3), whose1H nuclear magnetic resonance (NMR) spectra were examined and compared with those of four di-(R)-MTPA ester (3) diastereomers from chemically synthesizederythro (±)-3 andthreo (±)-3. To assign the- and-MTPA-OCH3 peaks, the1H NMR scans of several compounds that have substructures of 3 and their 3,4,5-trimethoxyphenyl analogues were examined. When a racemic alcohol reacts with (R)-MTPA to give a pair of (R)-MTPA ester diastereomers, the value was defined as the absolute value of the difference in the1H chemical shifts of the peak between the diastereomers. It was found that the values of-MTPA-OCH3 were larger than those of-MTPA-OCH3 owing to a shielding effect of the veratryl ring located on the-MTPA-OCH3, and that the-MTPA-OCH3 peaks in the 3,4,5-trimethoxyphenyl compounds shifted downfield relative to those in the veratryl compounds. On the basis of the1h NMR data of (R)-MTPA esters, the absolute configuration of the four chemically prepared diastereomers (3) were determined. The catabolicerythro
3 [fromerythro (-)-3] andthreo
3 [fromthreo (+)-3] were identical to (R, S, R)-erythro
3 and (R, S, S)- threo
3, respectively. An hydrogen species in the fungal reduction would attack the-ketone fromre-face of both (R)-1 and (S)-1, givingerythro (S, R)-2 andthreo (S, S)-2, respectively.Part of this paper was presented at the 33rd Lignin Symposium, Tsukuba, November 1988 相似文献
100.
Plasma N‐terminal pro‐B‐type natriuretic peptide concentration in healthy retired racing Greyhounds
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