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991.
992.
We caught the adults of a secondary wood-boring insect, Callidiellum rufipenne (Motschulsky), on Japanese cedar, Cryptomeria japonica D. Don., trees and logs with manipulated bark water contents to clarify the mechanism of host selection by C. rufipenne. More C. rufipenne were trapped when the bark water content range was ca. 120–200%. Fewer C. rufipenne were trapped at higher and lower bark water contents. These findings indicate that C. rufipenne adults do not simply select weakened or dying trees. Bark water content is one of important factors for C. rufipenne choosing their host for oviposition.  相似文献   
993.
994.
This article discusses the determinants of profitability expressed as return on capital among Japanese pulp and paper companies. Return on capital is measured as income before tax related to stockholders’ equity. Return on capital has been divided into profit margin and asset utilization rate. The hypothesis is that return on capital can be explained by mill size, productivity, product line, financial situation, and use of wood resources. The dataset consists of 13 larger Japanese pulp and paper companies listed in Pulp &; Paper Statistics. Data on financial performance, production, and use of wood fibers were collected for the period 1991–2001. The average return on equity for the studied companies is 4.2%. Labor productivity has increased quite significantly, from about 600 to 1,000 kg/employee and year. An econometric analysis indicates that the best model fit is found when the asset utilization rate is used as the dependent variable. Significant variables are, among others, asset utilization rate lagged one time period (?), labor productivity (+), capital productivity (?), paper production as a share of total paper and board production (?), total value of assets on the books (?) and solidity (+). This may indicate that the total value of assets on the books is large in relation to the total production of paper, paperboard and pulp.  相似文献   
995.
996.
Peroxidase plays important roles in many stress-related interactions and catalyzes important reactions in various physiological processes. Since peroxidase played critical roles in the evolution of almond(Prunus dulcis Miller(D.A Webb) syn P. amygdalus Batsch), peroxidase-gene-based analyses may increase the understanding of evolution of this species. Peroxidase gene polymorphism(POGP) markers were used to determine genetic diversity and relationships among 69 Turkish genotypes/cultivars and 27 foreign almond cultivars by using unweighted pair group method with arithmetic mean(UPGMA) analysis. This study is the first evaluation of the use of POGP markers for diversity analysis in almond.Totally, 83 fragments were obtained from eight peroxidase primer pairs, and polymorphism was identified as 94 %.Similarity level among the genotypes ranged between 0.63 and 0.93, and all materials were distinguished. In general,Turkish and foreign genotypes were mixed in clusters since they share a common genetic background and gene migration among the sites. Clusters were not based on geographic regions except for some minor groupings. This study indicated that peroxidase gene markers can be reliably used to determine genetic relationships in almonds.  相似文献   
997.
王松  田秀艳 《森林工程》2003,19(3):54-55
本文谈了我国混凝土建筑结构加固修复技术的现状、我国混凝土加固方法的工艺特点和存在的问题 ,并介绍了提高混凝土加固修复工程质量的基本对策  相似文献   
998.
FLORES, the Forest Land Oriented Resource Envisioning System, is a framework to facilitate quantitative modelling of ecological, economic and social issues at the landscape scale. This issue ofSmall-scale Forest Economics, Management and Policy describes the evolution of FLORES from a concept to a series of models calibrated for diverse locations, and documents the lessons learned. The idea to construct and use landscape-scale models of the forest frontier, based on simulating household decisions and land use at a spatial scale close to the field level, arose from a desire to add rigour to land-use policy research at CIFOR, the Center for International Forestry Research (Vanclay 1995). This simulation modelling approach to addressing interdisciplinary issues, where people are strongly interacting with forest resources, became known as FLORES, the Forest Land Oriented Resource Envisioning System (Vanclay 1998). Muetzelfeldtet al. (1998) constructed a simple prototype of a FLORES model to illustrate the concept and demonstrate the ability of a system-dynamics modelling environment to animate such a model (Muetzelfeldt and Taylor 1997, 2001, Muetzelfeldt and Massheder 2003). In 1999, FLORES became a reality, when 50 scientists from diverse disciplines met in Bukittinggi, Indonesia to construct the first FLORES model styled on this prototype (CIFOR 1999, Vanclayet al. 2003). The research reported in this special issue was made possible by generous financial support from the Department for International Development (UK), the European Community, the Asian Development Bank (under RETA 5812) and the Center for International Forestry Research. The views expressed herein are those of the authors alone. We would like to thank the following people who have assisted in the production of this special issue by acting as anonymous referees for these and other papers: Andy Warner, Brendan Moran, Bruno Verbist, Chris Dake, Chris Legg, Doug Sheil, Euan Mason, Francois Bousquet, Frank Vanclay, Geoff Slaughter, James Gambiza, John Herbohn, John Poulsen, Jungho Suh, Mike Spilsbury, Paul Phillips, Paul van Gardingen, Phil Norman, Philip Nyhus, Roger Wheate, Ross Sigley, Steve Harrison and Tom Evans. Thanks also to the editorial staff, especially Steve Harrison, John Herbohn and Jungho Suh, for making this special issue possible.  相似文献   
999.
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   
1000.
Forest commons are regarded as a means to support local development and sustainable forest conditions. To evaluate the development impact of Swedish forest commons, comparative surveys have been undertaken in three regions, and the differences in forest condition and management between categories of commons as well as their relation to other forest ownerships have been assessed. Regional differences between the by-laws, historical development and geographical conditions are apparent. It is concluded that two of three regions have an overly restrictive harvesting policy given the purpose of the forest commons and the official forest policy. The study results underline the importance of evaluation of the performance of forest management in relation to management objectives, to ownership alternatives and to the impact of local variations in preconditions.  相似文献   
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