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Forests are one of the most important ecosystems on earth that require careful management, conservation, and sustainable exploitation. As countries have their own guideline systems, each may learn and borrow from one another’s experience. One of such countries is Japan, which has elaborate forest policies, and rich in forest cover (67%) with its forest history dating many years back. On the other hand, Kenya, with a forest cover of just 7% and its policies demonstrating notable weaknesses, has a lot to learn from Japan. Therefore, we have attempted to do a comparative analysis of forest policies, technologies, and management practices between Kenya and Japan. Results indicate that Kenya’s forest policies do not place adequate emphasis on silvicultural practices and the establishment of forest plantations, and rarely focus on sustainable biomass utilization—factors that contributed significantly to forest growth and development in Japan. Additionally, policy legislation, revision, and implementation have not been given the deserved priority in Kenya. We conclude that Kenyan forest policy would benefit from both revision and thorough implementation. We also discuss the role of indirect factors such as economic growth and availability of nonwood-based energy sources in the future of Kenya’s forests.  相似文献   
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In aquatic ecosystems, the stable nitrogen isotope ratio (δ15N) of wakame is affected by the δ15N of its nitrogen source. Thus, the δ15N of wakame is thought to differ between those grown in different aquatic ecosystems. To confirm the authenticity of the geographic origin of Naruto dried wakame (DW), we conducted δ15N analysis. The δ15N (mean ± σ) of Naruto DW model samples (n = 72) was 11.1 ± 1.9 ‰. The δ15N confidence range of Naruto DW from the model was 5.3–16.9 ‰ (mean ± 3σ). The δ15N values of the DW model of Chinese (n = 23) and South Korean origin (n = 22) were 4.2 ± 1.4 and 1.6 ± 2.3 ‰, respectively. Within the δ15N confidence range of Naruto DW, two model samples of Chinese DW and one model sample of South Korean DW were found. From those results, DW of Naruto origin was able to be distinguished from DWs of the Chinese and the South Korean.  相似文献   
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After mechanized whole-tree harvesting at a clear cutting site, using a cable yarding system and a processor, piles of slash remain at the landing areas near roads. This study examined the movement of slash piles and their effect on soil nutrients in the ground below the pile. The profile of one pile was measured for three years. In order to investigate nutrient concentrations, soil was sampled at two sites. The volume of the pile decreased by 6% per year. Piles placed on convex or uniform hillsides are stable, and have a low risk of sliding on a slope. Analysis of the water-soluble nutrients in the soil suggests that water carries nutrients from the pile into the soil up toca. 7 m from the pile. There is a reduction in soil acidity, and rainwater flow from the pile adds several minerals to the soil, particularly Ca. Slash in a pile on a convex or uniform hillside does not have any impact on a forest, either positively or negatively. We should try to return slash to stands or utilize it as a biomass resource. This study was supported by a Grant-in-Aid of Scientific Research (No. 09660164) from the Ministry of Education, Science, and Culture, of Japan.  相似文献   
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 Whole-tree harvesting at clearcutting sites using cable yarding systems and processors disrupts the process of nutrient return via leafy and woody slash otherwise left on the forest floor. This study examined the effect of placing slash chips around trees planted in a clearcut area. Chips made from branches with needles (branch chips) and three types of wood scrap chips (wood chips) were prepared for the study. Changes in the thickness of slash chip layers and in the concentration and weight of decomposing chips were measured. The nutrient effect of applying chips to the soil was analyzed, and the effects of chip coverage on weed control were measured. The branch and 18-mm-thick wood chips were stable on slopes; 9- and 4-mm-thick wood chips readily shifted to the lower and outer positions in the plots. On branch chips and wood chips, the annual rate of decomposition (k) calculated by exponential model was 0.69–0.7 and 0.04–0.17/year, respectively. Branch chips provided more nutrients for decomposers, and were rapidly decomposed during the first month. Nevertheless, the nutrient effect on the soil could not be confirmed. Placing branch or wood chips around planted trees effectively eliminated the need for weeding for 1 year, but these light materials did not suppress shrub sprouting. Received: November 14, 2001 / Accepted: September 26, 2002 Acknowledgments The authors thank the graduates of Kochi University, especially Ms. Y. Shinnobu, Ms. A. Fujita, Ms. A. Sugiyama, and Ms. Y. Suzuki for their help with the field work and chemical analyses. This study was supported by a Grant-in-Aid for Scientific Research (No. 09660164) from the Ministry of Education, Culture, Sports, Science and Technology of Japan. Correspondence to:J. Gotou  相似文献   
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To evaluate the effect of cooled and chlorinated chill water for Campylobacter and coliforms at a middle-size processing plant which was considered to be difficult for eliminate pathogenic bacteria on carcasses, following three conditions were examined; keeping temperature at < 20, < 10 and < 10°C, and chlorine concentration at < 50, < 50 and 50 to 70 ppm during processing in experiment 1, 2 and 3 respectively. Fifteen prechill and 15 postchill carcasses were examined in each experiment. In lower temperature of experiment 2, decreasing rate (%) of coliforms was significantly higher (P<0.01) than that in experiment 1. In higher chlorination of experiment 3, no Campylobacter was detected from all postchill carcasses.  相似文献   
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