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41.
Diosdado A. Paler Takeo Shinohara Romulo A. del Castillo Isamu Nomura 《Journal of Forest Research》1998,3(4):193-197
The study describes the development of industrial tree plantation in a specific region in the Philippines. Two case studies
using plantation companies are presented. Likewise, management prospects and problems are considered. Since industrial plantations
are given emphasis in the 1980’s, plantation owners are already capable to engage in development. Although majority are small
scale, their management performance is considerable. Likewise, social and economic gains are enormous. Fast growing species
for pulpwood are developed under different climatic conditions at low stocking density. However, further development is limited
by problems particularly product development, financial assistance, and the volatility of plantation policy. Several approaches
are endorsed.
The study is partially funded by the Sasagawa Research Foundation of the Japan Science Society. Sincere appreciation is extended. 相似文献
42.
Diosdado A. Paler Takeo Shinohara Romulo A. del Castillo Isamu Nomura 《Journal of Forest Research》1998,3(3):139-143
The characteristics of timber production in the public forest of a specific region in the Philippines are examined and the
patterns on the linkages between logging, deforestation, and socio-economic development are established and illustrated. The
logging industry is fully manned and financially capable and is a major contributor to the economy. However, the industry
is now shrinking due to the declining forest resource of the region. The end results eventually lead to reduced productivity
and contribution. The reduction of forest resources was traced to the excessive commercial logging and agricultural conversion
of forest lands. Alternatives are suggested.
The assistance provided by Mr. Jose D. Malvas, Jr., Director of the Forest Management Bureau, in the gathering of the data
used in the study is deeply appreciated. 相似文献
43.
Ozawa Hideo Yamamura Akira Kimijima Takeo Ishizaki Shoichiro Ochiai Yoshihiro 《Fisheries Science》2020,86(1):197-202
Fisheries Science - Tropomyosin (TM) is the major allergen found in invertebrates, including shrimp. To reduce the allergenicity of shrimp muscle, attempts were made to eliminate TM from the muscle... 相似文献
44.
Fukai K Onoda H Itou T Sato M Miura Y Sakai T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(11):1413-1416
G8 bovine group A rotaviruses isolated in Japan were genetically and serologically characterized. The VP7 gene nucleotide and amino acid sequences revealed high identity with each other. All Japanese G8 strains were classified into the same lineage in the phylogenetic analysis based on VP7 gene sequences. Antisera to four Japanese G8 strains neutralized other G8 strains, but their neutralizing titers were between 8-fold lower and 2-fold higher than homologous strains. These results suggest that the VP7s of Japanese G8 strains have similar genetic and serologic characteristics. Observed differences in the neutralizing abilities of antisera for each strain appear to depend on differences in the P serotypes/genotypes. 相似文献
45.
Transections of the brain of rabbit reveal that electroencephalographic arousal produced by injections of adrenaline takes place at the midbrain level, while mescaline and 3,4-dimethoxyphenylethylamine induce such arousal lower in the brainstem, at the medullary level. 相似文献
46.
47.
祁门红茶的香气特征 总被引:26,自引:7,他引:26
通过对祁红当家品种——槠叶群体种及其适制绿茶的亲缘种——安徽7号(对照)在加工红茶的过程中香气形成的动态分析和比较研究表明,在祁红检出的110多种香气成分中,己醛,1-戊烯-3-醇、反-2-己烯醛、顺-3-己烯醇、芳樟醇氧化物Ⅱ、芳樟醇、香叶醇、橙花叔醇等含量较高。在相同的祁红加工过程中,槠叶群体的香气物质形成总量高于对照,且形成高峰超前,其中香叶醇含量在揉捻阶段剧增;与安徽7号相比,香叶醇含量高出30倍以上,而其他香气成分含量则无明显差异。实验还发现,两品种茶叶在加工过程中,儿茶素的减少与茶叶香气总量及其中的萜烯醇类的增长均具有很好的对应关系,槠叶群体中有关香气配糖体的含量高于安徽7号,文中对此作了讨论。 相似文献
48.
Kyi Moe Seinn Moh Moh Aung Zaw Htwe Takeo Yamakawa 《Journal of plant nutrition》2013,36(15):1726-1739
We investigated the effects of poultry manures (PM) and cow manures (CM) using estimated mineralizable nitrogen (EMN) method on nitrate, nutrient content and growth parameters of komatsuna and compared with chemical fertilizer (CF) in an abandoned soil. We applied manures as EMN based on their total N content. The 100% of EMN by PM or CM enhanced dry matter (DM) but depressed nitrate content. The PM-Keifun (PMK) with total N (4.87%) produced greater growth parameters, DM, nutrient content and lower nitrate content but manures with total N (<2%) could not. The solo CF150 did not promote leaf number but increased nitrate and Na content. In conclusion, a higher total N (>4%) concentration of manure led to increase availability and nutrient contents, DM, and depressed nitrate content of komatsuna, comparable with solo CF in an abandoned soil. 相似文献
49.
The carbohydrates in soil organic matter seem to be derived from undecomposed or partially decomposed plant and microbial residues, In soil, these carbohydrates exist chiefly in such from as polysaccharide hemicellulose, and their polyuronide has been the chief object of investigation1)-3). In various soil, the polyuronide is found in a large quantity in fulvic fraction of soil organic matter and has been considered as important in connection with the physical structure of soil4),5). According to Lynch 5), the carbohydrate content of humic acid is markedly smaller than that of fulvic acid. His work also indicates that a' considerable change is noted in the content and composition of the carbohydrate in humic acid because of the addition of some organic substances to the soils, or of the cultivation of virgin soils. Further, some investigators7) believe that uronic acid is introduced into the aromatic structure of the humic acid by changing into pentose and furan. Accordingly, it seems that the role of carbohydrate in the formation of soil humic acid should not be overlooked. 相似文献
50.
Five barley cultivars were grown together in complete, low-P·low-pH and high-Al medium containing only NO3, only NH4 or both NO3 and NH4 as N sources, respectively using an automatic control system of pH for water culture, and the relationship between the differential Al tolerance and the plant-induced pH change of medium among the barley cultivars was investigated. The pH of the medium containing only NO3 as N source tended to increase, whereas the pH of the other media containing only NH4 or both NO3 and NH4 as N sources tended to decrease, but the fluctuations of the medium pH could be maintained within the value of 0.2 pH in the complete medium and within the value of 0.1 pH in the high-Al medium. Barley cultivars still differed in their Al tolerance in the medium which was continuously stirred and circulated at a constant pH. The pattern of Al tolerance was not affected by the N sources in the medium. The plant-induced pH change of medium for each cultivar was influenced by the N sources in the medium, and was not correlated positively with Al tolerance. The contents of Al and Ca or other nutrient cations in roots were positively correlated with Al tolerance and positive correlations were recognized also between the contents of Al and Ca or some other nutrient cations in the roots. In conclusion, the following mechanisms are proposed. Al tolerant barley cultivars exclude Al actively outside the plasmalemma of the root cells, and the excluded Al may polymerize and or react with P to form Al precipitates. Consequently, in the Al tolerant barley cultivars the Al content may be low in the root protoplasts, high in the whole root tissues and the contents of Ca or other nutrients may be high in the roots. The plant-induced pH change of medium is not considered to be the cause of the differential Al tolerance among barley cultivars. 相似文献