Growth Characteristics of Dwarf Bamboo Distributed in the Northern Part of Japan

Dwarf bamboo is a dominant forest floor species, especially in the northern part of Japan. Sasa kurilensis, Sasa senanensis and Sasa nipponica are widely distributed in this region. Growth characteristics of these three Sasa species are also different: leaf longevity of S. kurilensis is 3–5 years. In contrast, leaf longevity of S. senanensis and S. nipponica are 2 years and <1 year, respectively. We predicted that ecophysiological characteristics of the three Sasa species would reflect their leaf longevity; however, their characteristics were still not well analysed. We examined ecophysiological parameters of the three Sasa species grown under the same environment. Net photosynthetic rate at light saturation (Psat) and nitrogen concentration (N) of S. nipponica showed high values after flushing. However, culms of S. nipponica were dropped after overwintering, and Psat of the 2-year-old leaves drastically decreased. Meanwhile, Psat of the current leaves of S. kurilensis was lower than the other two species. However, Psat of 2-year-old leaves of S. kurilensis still maintained a relatively high value. Psat of the current leaves of S. senanensis was higher than that of S. kurilensis even though N was the same. From these results, S. senanensis had a high photosynthetic nitrogen efficiency rate (Psat/N)

Comparison of Foliar Defense by Chemical Analysis and Bioassay in Betulaceae Seedlings

北海道大学京都大学Proceedings : IUFRO Kanazawa 2003 "Forest Insect Population Dynamics and Host Influences"., Scedule:14－19 September 2003, Vemue: Kanazawa Citymonde Hotel, Kanazawa, Japan, Joint metting of IUFRO working groups : 7.01.02 Tree resistance to Insects | 7.03.06 Integrated management of forset defoloating insects | 7.03.07 Population dynamics of forest insects, Sponsored by: IUFRO-J | Ishikawa Prefecture | Kanazawa City | 21st-COE Program of Kanazawa University, Editors: Kamata, Naoto | Liebhold, Nadrew M. | Quiring, Dan T. | Clancy, Karen M

Effects of Defoliation on Defense Characteristics in Leaves of Deciduous Broad-Leaved Tree Species in Changing Environment

北海道大学Forestry and Forest Products Research InstituteScedule:17-18 March 2003, Vemue: Kanazawa, Japan, Kanazawa Citymonde Hotel, Project Leader : Hayakawa, Kazuichi, Symposium Secretariat: XO kamata, Naoto, Edited by:Kamata, Naoto

Does the root to shoot ratio show a hormetic response to stress? An ecological and environmental perspective

Root/shoot (R/S) ratio is an important index for assessing plant health, and has received increased attention in the last decades as a sensitive indicator of plant stress induced by chemical or physical agents. The R/S ratio has been discussed in the context of ecological theory and its potential importance in ecological succession, where species follow different strategies for above-ground growth for light or below-ground competition for water and nutrients. We present evidence showing the R/S ratio follows a biphasic dose–response relationship under stress, typical of hormesis. The R/S ratio in response to stress has been widely compared among species and ecological succession classes. It is constrained by a variety of factors such as ontogeny. Furthermore, the current literature lacks dose–response studies incorporating the full dose–response continuum, hence limiting scientific understanding and possible valuable application. The data presented provide an important perspective for new-generation studies that can advance current ecological understanding and improve carbon storage estimates by R/S ratio considerations. Hormetic response of the R/S ratio can have an important role in forestry for producing seedlings with desired characteristics to achieve maximum health/productivity and resilience under plantation conditions

Leaf Longevity and Defense Characteristics in Trees of Betulaceae

北海道大学Foresty amd ForestProducts Research Institute(FFPRI)Hokkaido Research center, FFPRIProceedings : IUFRO Kanazawa 2003 "Forest Insect Population Dynamics and Host Influences"., Scedule:14－19 September 2003, Vemue: Kanazawa Citymonde Hotel, Kanazawa, Japan, Joint metting of IUFRO working groups : 7.01.02 Tree resistance to Insects | 7.03.06 Integrated management of forset defoloating insects | 7.03.07 Population dynamics of forest insects, Sponsored by: IUFRO-J | Ishikawa Prefecture | Kanazawa City | 21st-COE Program of Kanazawa University, Editors: Kamata, Naoto | Liebhold, Nadrew M. | Quiring, Dan T. | Clancy, Karen M

Ethylenediurea (EDU) effects on Japanese larch: an one growing season experiment with simulated regenerating communities and a four growing season application to individual saplings

Japanese larch (Larix kaempferi (Lamb.) Carr.) and its hybrid are economically important coniferous trees widely grown in the Northern Hemisphere. Ground-level ozone (O3) concentrations have increased since the pre-industrial era, and research projects showed that Japanese larch is susceptible to elevated O3 exposures. Therefore, methodologies are needed to (1) protect Japanese larch against O3 damage and (2) conduct biomonitoring of O3 in Japanese larch forests and, thus, monitor O3 risks to Japanese larch. For the first time, this study evaluates whether the synthetic chemical ethylenediurea (EDU) can protect Japanese larch against O3 damage, in two independent experiments. In the first experiment, seedling communities, simulating natural regeneration, were treated with EDU (0, 100, 200, and 400 mg L−1) and exposed to either ambient or elevated O3 in a growing season. In the second experiment, individually-grown saplings were treated with EDU (0, 200 and 400 mg L−1) and exposed to ambient O3 in two growing seasons and to elevated O3 in the succeeding two growing seasons. The two experiments revealed that EDU concentrations of 200–400 mg L−1 could protect Japanese larch seedling communities and individual saplings against O3-induced inhibition of growth and productivity. However, EDU concentrations ≤ 200 mg L−1 did offer only partial protection when seedling communities were coping with higher level of O3-induced stress, and only 400 mg EDU L−1 fully protected communities under higher stress. Therefore, we conclude that among the concentrations tested the concentration offering maximum protection to Japanese larch plants under high competition and O3-induced stress is that of 400 mg EDU L−1. The results of this study can provide a valuable resource of information for applied forestry in an O3-polluted world

Essential Role of Symbiotic Microorganisms Supporting Forests in East Asia under Changing Environment

Regeneration success of forests is strongly dependent on symbiotic microorganisms, that is, arbuscular mycorrhiza (AM) and ectomycorrhiza (ECM). In the northeastern part of Asia, larch and birch are used as timber resources, and in the south, fir, cedar, cypress, and oak are used as timber resources. Planted forests have reached the time of harvesting and/or thinning, and after the forestry practices, it is expected that they will become mixed forests equipped with resistance to weather damage; that is, drought, heat, typhoons, etc. On the other hand, the physical production environment has changed greatly, therefore, we investigated the growth of the major trees and the role of mycorrhizal fungi in the northeastern Asia. Elevated O3 decreased growth, colonization rates of ECM, and the biodiversity; however, elevated CO2 moderated or increased them in larch. Except for disease of rot and damping off, we discuss wise use of symbiotic microbe in far East Asia

個葉からみたブナ背腹性の生理的側面

[招待論文

Environmental and Education Trials for Mangrove Ecosystem Rehabilitation in China

Based on Chinese ecological policy, we have been studying mangrove ecosystems in southern China, especially from the perspective of pollutants deposition in mangrove wetlands, physiological ecology of mangrove species on the impact of heavy metal pollution and seeking ecosystem restoration. For these, we explored in three aspects: 1) pollutants distribution and ecological risk in main distribution of mangrove, China, 2) eco-statistics and microbial analyses of mangrove ecosystems (including shellfish) in representative locations where mangrove plants are well developed, especially in Shenzhen, a rapid developing economic city in Guangdong Province, 3) ecophysiological experiments on a representative species of mangrove for evaluating combination effects of major nutrient elements and heavy metal pollution on growth and physiological responses of the seedlings. Based on the results, we proposed how to rehabilitate mangrove ecosystem in China under rapidly changing environmental conditions, with a view to our future survival and to provide nature-based solution as well as the public with more ecosystem services

Removal of accidentally ingested large foreign object via the anus after watchful waiting

One of the commonest complaints, for which a patient arrives in hospitals, is the presence of foreign body. It could be due to&nbsp;accidental ingestion or any other cause which leads to presences of a foreign body in the gastrointestinal tract. It is believed that&nbsp;foreign objects larger than 5–6 cm in size are unlikely to pass through the duodenum. Here, we describe a case wherein the patient&nbsp;accidentally swallowed a 7-cm-sized mouthguard that could not be removed by emergency upper gastrointestinal endoscopy but was&nbsp;subsequently removed via the anus after a period of watchful waiting