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1.
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   
2.
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   
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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   
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ABSTRACT:   Five loci ( Phz2 , Phz6 , Phz7 , Phz12 , and Phz14 ) of microsatellite DNA markers developed in a previous study for parentage assignment in the hatchery population generated by mating among 61 broodstock fish (35 females and 26 males) in a spawning tank, were selected. After natural spawning in the same tank, larvae collected at three different times were categorized into early phase (EP), middle phase (MP), and late phase (LP) groups. In the parental broodstock, the mean number of alleles per locus was 21.8 and expected heterozygosity ( H E ) was 0.813. In the progeny, the mean number of alleles per locus decreased to 11.6 (EP), 14.4 (MP), and 6.4 (LP) and H E to 0.796 (EP), 0.833 (MP), and 0.681 (LP). Parental assignment determined eight dams and six sires as major parents for the EP group. In the MP group, 13 dams and ten sires genetically contributed to spawning, but only three dams and two sires were involved in LP group progeny. In the hatchery population produced from a limited number of parental fish such as the LP group, genetic variability was apparently decreased.  相似文献   
8.
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   
9.
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   
10.
Nagashima  Keiko  Sands  Roger  Whyte  A.G.D.  Bilek  E.M.  Nakagoshi  Nobukazu 《Landscape Ecology》2001,16(8):719-729
The expansion of plantation forestry in New Zealandduring the last century has altered the landscape and will continue to do so in the future. The implementation of recent resource management policy, the 1991 Resource Management Act (RMA), will also influence the impact of future plantation expansion on the landscape. It is necessary to analyze current land-use patterns in order to predict effects on future landscapes. This study analyzed the current land-use patterns of the Nelson region by examining the relationship between land-use and site conditions and by characterizing the distribution pattern of land-use depending on distance from the city. The distribution pattern was considered from an economic perspective, based on the Barlowe’s model of land use distribution. The relationship between the current land-use pattern and previous land management policy was also examined using the Land Use Capability. Consequently, in addition to the physical attributes of the land, the influence of land-use management policy was obvious. Thus the RMA will undoubtedly influence land-use changes in the future. It is therefore necessary to understand the factors determining changes in land-use patterns in conjunction with the district plan of the RMA to predict future changes in land-use.This revised version was published online in May 2005 with corrections to the Cover Date.  相似文献   
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