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1.
Amin Setyo Leksono Kenta Takada Nobukazu Nakagoshi Koji Nakamura 《Journal of Forest Research》2006,11(1):61-64
A continuous sampling of canopy beetles was carried out to determine variations in the abundance, species diversity, richness,
and composition of the Mordellidae and Cerambycidae in a coppice woodland. Changes in the abundance and the species richness
were monitored at three heights in the forest throughout the season in 1999, using yellow and blue water pan traps. The results
showed significant variations in the abundance of Mordellidae among the canopy layers, while little variation was found for
Cerambycidae. The abundance, species diversity, and richness were generally greater in summer. The results showed distinct
species compositions in both families among layers. 相似文献
2.
Nobukazu SAISHU Kazutaka MORIMOTO Hiroshi YAMASATO Hiroichi OZAKI Toshiyuki MURASE 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(9):1037-1042
Thirty-eight Aerococcus viridans isolates were obtained from milk from
478 cows with clinical mastitis in a farm during the periods between November 2011 and
February 2012, and between December 2012 and March 2013. Additional isolates were obtained
from processed manure (a mixture of composted manure, straw and hydrated lime) and bedding
materials. The processed manure was later used to cover the floor of the stalls in barns
as bedding materials. The temperatures recorded in the composted and processed manure were
not as high as those generally observed during satisfactory composting. To reveal the
association of A. viridans in manure-related products with intramammary
infection in cows, isolates were characterized by their DNA fragment patterns as
determined by pulsed-field gel electrophoresis (PFGE) and antimicrobial susceptibility
testing. Isolates obtained from milk, processed manure and bedding materials had identical
DNA fragment patterns. Antimicrobial susceptibilities were determined for 29 isolates from
milk, processed manure and bedding materials. Of these, 26 (89.7%) were resistant to
clindamycin, whereas virtually all the isolates were susceptible to 12 other
antimicrobials including cefalosporins that have been used to treat bovine mastitis in
Japan. In vitro, three A. viridans isolates from milk
and an isolate from processed manure survived for 3 hr in Good’s buffer (pH 9) at high
temperature (50°C). The results suggest that the processed manure and bedding materials in
this farm were possible sources of A. viridans that caused infection in
the cows with mastitis. 相似文献
3.
4.
Landscape enhancement projects are under way at the Yamanakadani and Kadowaki rivers, which run through the campus of Hiroshima University, Japan. At both sites, the ecological value of land was determined from two aspects: (1) value as vegetation and (2) value to birds. To evaluate the vegetation, we selected conservation sites and suitable sites for enhancement considering rarity and recovery potential of vegetation, and access to users and construction equipment. We determined that the area of forest, the number of forest vertical layers, and forest pattern help sustain avian diversity and contribute toward the area functioning as an avian corridor. 相似文献
5.
Community-based management of a rural pine forest in a small suburban community, was examined and assessed. In particular,
the study focused on theMatsutake project, which is an initiative seeking to help in the maintenance of a communal pine forest via the cultivation of theMatsutake mushroom by a local seniors’ group. From an ecological perspective, the maintenance work is found to be effective in the
conservation and regeneration of the pine forest ecosystem, including its species diversity, especially in the herb layer.
From a sociological perspective, theMatsutake project presented a valuable opportunity to strengthen connections not only within the seniors’ group, but also between senior
citizens and other generations. However, subsidies for the project have tended to be gradually reduced, because it is difficult
for non-involved community members to appreciate the benefits of the project. For the project to be sustainable, more widespread
participation of the community is essential. A framework for wider analysis of local participatory forest management is also
deemed necessary. 相似文献
6.
On Shimokamagari, an island of the Seto Island Sea, patterns of vegetation in the landscape were studied using vegetation
maps. Relationships between social and economic changes, site conditions and the vegetation were examined from a historical
perspective. In the process of economic development, mandarin orange production became important on this island. However,
over-production, a reduction in the price of mandarin oranges and low-temperature damage to orange trees caused large citrus
orchards to be abandoned. A plant community dominated by kudzu appeared in the abandoned orchards and the pine forests, as
well. These changes in orchards were connected with the natural site conditions, such as soil, geology, inclination, elevation,
direction of slope, and also with artificial conditions, such as density of working paths. Another factor causing change was
the replacement of the organic fertilizer of litter from forests by chemical fertilizer since the 1960's. As a result, medium
and small forests of pine became tall forests and tall forests of pine changed into tall oak forests. In the human-dominated
areas, the major factors affecting the process of vegetation were economic activities, and after the abandonment of the farm-lands,
forest succession were controlled by natural site conditions.
This paper was presented at the World-Congress of Landscape Ecology in Ottawa, 1991
Titles are tentative translations for original titles in Japanese by the authors. 相似文献
7.
Landscape structure and the disturbance regime at three rural regions in Hiroshima Prefecture,Japan 总被引:7,自引:1,他引:6
Using the vegetation maps of island, inland and mountainous rural regions in Hiroshima Prefecture in western Japan, landscape structures in terms of the size and number of patches are compared, and the characteristics of the disturbance regimes creating each landscape are discussed. Landscape structure in the island rural region is the most heterogeneous, because factors which alter the landscape structure are the most complex. This heterogeneity is established and kept by the agricultural land uses and natural disturbances such as forest fire and pine-disease. At the mountainous rural region, the landscape mosaic is characterized by the relatively large patches composed of conifer plantations and secondary deciduous oak forests. This is the result of the forestry. The inland region landscape is the most homogeneous, because factors which alter landscape structure are now absent. The complex of the physical, biological and anthropogenic forces makes the landscape unique to each region. 相似文献
8.
Yoshinori Tokuoka Kentaro Ohigashi Koji Watanabe Hiroshi Yamaguchi Takahiro Ara Nobukazu Nakagoshi 《林业研究》2016,27(6):1287-1294
Natural forest recovery on abandoned farmland is hindered by a variety of factors and active restoration plays an important role when quick afforestation is desired. We investigated seedling survival of four transplanted native tree species (Quercus myrsinifolia, Quercus serrata, Aphananthe aspera, and Rhus sylvestris) by experimentally manipulating the vegetation cover, which was mainly dominated by dwarf bamboo (Pleioblastus chino), and herbivore access to the planting sites on farmland that had been abandoned for 15 years at the start of the study. Few transplanted seedlings of any species survived under intact vegetation cover, irrespective of herbivore presence. In gaps in the vegetation cover, winter browsing by Japanese hare (Lepus brachyurus) damaged all species. However, lower browsing frequency and higher resprouting ability after grazing of the seedlings enabled both Quercus species to survive better than the other species. These results indicate that dwarf bamboo and the hare jointly limit the establishment of native trees in old fields. If active afforestation by transplanting seedlings at sites dominated by dwarf bamboo is planned, a combination of vegetation removal, selection of suitable species, and temporary seedling protection will be most effective. 相似文献
9.
Recently, it is documented that bamboo (Mousouchiku:Phyllostachys pubescens Mazel) invasion deteriorates ecological and/or landscape diversity. In order to investigate the ecological effects on forest-floor
arthropods caused by bamboo invasion, we compared the myrmecofauna among broadleaf forests, bamboo-broadleaf mixed forests,
and bamboo forests in Hiroshima City and its vicinity. Myrmecofauna in bamboo forests were more impoverished than in broadleaf
forests. Myrmecofauna in the mixed forests, however, were similar to that in broadleaf forests in both species diversity and
species composition. The change in myrmecofauna may occur relatively late after the initial bamboo invasion. 相似文献
10.
Nobukazu Satoh Shigeharu Nobuta Motoomi Wakasugi Shuichi Satoh Toshio Takeuchi 《Fisheries Science》2013,79(2):259-267
Two 12-week feeding experiments were conducted to evaluate the nutritional value of squid viscera meal with cadmium removal treatment (dCSVM), which contained 1.5–2.0 mg/kg cadmium, as an alternative protein source to sardine meal in diets for fingerling black rockfish Sebastes schlegeli. Initial mean body weights in experiments 1 and 2 were 23.0 and 6.4 g, and the replacement rates of sardine meal with dCSVM in the test diets were 20–80 % and 30–60 %, respectively. In experiment 1, inclusion of dCSVM at 40 % and higher replacement rates of sardine meal retarded the growth of fish due partly to inferior dCSVM protein digestibility. The cadmium (Cd) concentrations in fish muscle of all treatment groups were below the detection limit (<0.1 mg/dry matter). In experiment 2 using dCSVM containing Cd at a lower level and having a higher protein digestibility than in experiment 1, no significant differences were observed in the growth between the control and 60 % replacement groups, although feed efficiency gradually decreased with the increase of dCSVM inclusion. These results show that dCSVM is safe and useful as an alternative protein source and could replace up to 60 % of sardine meal in fingerling black rockfish diets. 相似文献