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161.
162.
Zhang Jin-Chi Zhuang Jia-Yao Su Ji-Shen Nakamura Hiroyuki Ishikawa Haruyoshi Cheng Peng Fu Jun 《Forest Ecology and Management》2008
Land use plays an important role in soil loss and other environmental problems. Correct prediction of soil loss from different types of land use is very important to land use policy making in the Dabie Mountains, China. Field observations of water and soil loss were carried out in the Shangshe catchment in four types of land use in 1999–2002. This paper reports the study of soil loss in the sub-catchment of Chinese fir forest. 相似文献
163.
Yasuyuki Tachiki Tetsuhiko Yoshimura Hisashi Hasegawa Tomonori Mita Tetsuro Sakai Futoshi Nakamura 《Journal of Forest Research》2005,10(6):419-427
The objectives of this study were to determine Global Positioning System (GPS) positional errors while moving under the forest
canopy and to clarify the effects of polyline simplification on area and perimeter estimations. We used the Pathfinder Pro
XR and GPSMAP 76S, which are categorized as “high-end mapping” and “general navigation” GPS receivers, respectively. The field
tests were conducted in both natural and plantation forests. The results showed that the Pathfinder Pro XR, which has better
multipath rejection technology, worked well, especially in the plantation forest under unfavorable conditions of higher stand
density. We used analysis of variance to clarify the effects of the receiver type, positioning mode, stand type, and polyline
simplification method on area and perimeter estimations. The receiver type and positioning mode were found to be significant
factors that affected area estimation. The Pathfinder Pro XR estimated the area more accurately than the GPSMAP 76S, and differential
GPS estimated the area more accurately than autonomous GPS. With respect to the perimeter, the receiver type, positioning
mode, and polyline simplification method were found to be significant factors. The results showed that perimeter estimation
was improved by using the velocity filter, and further improved by using the velocity filter and Douglas-Peucker algorithm,
especially when the Pathfinder Pro XR was used. The GPSMAP 76S estimated the perimeter accurately without any filtering because
its default speed filter worked well, even though the GPSMAP 76S is a general navigation GPS receiver. 相似文献
164.
Kokoro Kikuchi Takumi Akasaka Yuichi Yamaura Futoshi Nakamura 《Journal of Forest Research》2013,18(5):389-397
The conservation of cavity trees in plantations is important for maintaining biodiversity because cavity trees are one of the forest attributes most strongly affected by forestry operations. We surveyed the occurrence of cavities at the tree-level and the abundance of cavity trees and the number of uses by secondary cavity users at the stand-level in natural and conifer plantation forests in Hokkaido, Japan. We classified cavities into two types by their formation processes: excavated and non-excavated. Excavated cavities were more common in dead trees than in live trees. Non-excavated cavities showed high occurrence in dead and live broad-leaved trees. The abundance of non-excavated cavity trees was two times greater than that of excavated cavity trees in natural forests, but, in plantations, excavated cavity trees were dominant. The abundance of non-excavated cavity trees was lower in thinned plantations than in not-thinned plantations. The number of cavity uses increased with the number of cavity trees, indicating the importance of maintaining cavity trees. Conifer plantations are established by removing native broad-leaved trees, which results in a lower abundance of non-excavated cavity trees in these locations. The conservation of broad-leaved trees is important for maintaining the current and future resource of non-excavated cavity trees in plantation forests, as is the conservation of dead trees, which showed a high occurrence of excavated cavities. 相似文献
165.
Mariko Takano Muneysohi Yamaguchi Hiroaki Sano Masaya Nakamura Hajime Shibuya Yasumasa Miyazaki 《Journal of Wood Science》2013,59(2):141-148
The gene encoding manganese peroxidase of a white-rot fungus Phanerochaete crassa WD1694 was cloned and sequenced. Four genomic clones were sequenced in which 3 clones were existed as alleles. The analysis of intron–exon structures divided the 4 clones into three subfamilies that corresponded to mnp2 and mnp3 of Phanerochaete chrysosporium, and a new subfamily possessing only five introns. The purified P. crassa WD1694 MnP consisted of 4 isozymes with same molecular weight, same N-terminal sequence, and different pI. N-terminal sequence of deduced protein of P. crassa mnpB3 gene was identical to those of 4 MnP isozymes; however, the other 3 mnp genes had different N-terminal sequence. The molecular weight of encoded mature protein of mnpB3 gene and purified MnP had a gap that could be difference between MnP proteins encoded by single gene. The results suggested that 4 MnP isozymes of P. crassa WD1694 arose from single gene. 相似文献
166.
Shun-ichiro Takano Atsushi Mochizuki Keiji Takasu Kazuhiko Konishi Jelfina C. Alouw Donata S. Pandin Satoshi Nakamura 《Journal of pest science》2013,86(2):151-155
Brontispa longissima (Coleoptera: Chrysomelidae) is a serious invasive pest of coconut palm (Cocos nucifera) supposedly originating from Indonesia and New Guinea. It has recently invaded Southeast and East Asia, where it has caused serious damage to coconut plants. Brontispa longissima as currently defined contains two cryptic species: we herein referred to one as the “Asian clade”, which is distributed over a wide area, including Asia and the Pacific region; and we referred to the other one as the “Pacific clade”, which is found in a limited area in the Pacific region. We developed a PCR–RFLP method for differentiating the two clades. Digestion of the PCR product of a 1,014-bp region within the mitochondrial cytochrome oxidase I gene (COI) with BslI, HpyCH4III, or NlaIV resulted in clade-specific patterns as estimated by the sequence data. We applied the method to specimens newly obtained from various locations to investigate the geographical distribution of B. longissima. Although B. longissima collected from Samoa in April 2003 had been placed in the Pacific clade, specimens collected from the same island in April 2010 were placed in the Asian clade, suggesting that the predominant clade may have been changing from the former to the latter. On Timor, specimens included both clades in apparently segregated habitats. 相似文献
167.
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
168.
Chikaya Sakai Atok Subiakto Hani Sitti Nuroniah Naoto Kamata Koji Nakamura 《Journal of Forest Research》2002,7(2):73-80
We developed a vegetative propagation system for mass-producing three dipterocarps species,Shorea selanica Bl.,Shorea leprosula Mig., andShorea platyclados Sloot. This system uses fog evaporative cooling inside a greenhouse to reduce the leaf-to-air vapor pressure deficit (leaf-to-air
VPD) inside the propagator, even under high irradiance conditions. This cooling method has no negative influence on medium
conditions such as overwetting. A plastic tent propagator combined with this cooling method was used for vegetative propagation
experiments. In mass-production experiments, the annual rooting percentages from the cuttings were low in the first 2 years
(1997–1998) due to operational problems of the tent propagator (S. selanica, 48–51%;S. leprosula, 56–59%;S. platyclados: 50–63%). A hard cover propagator improved the rooting percentages in the mass-production experiments in 1999 because it
made operations easier (S. selanica, 70%;S. leprosula, 77%;S. platyclados, 77%). This system, which uses a combination of fog evaporative cooling and a hard plastic propagator, should be useful for
the mass propagation of these dipterocarp planting stocks.
This study was carried out under a joint project of the Ministry of Forestry, Indonesia and Komatsu Ltd. The project was supported
by Research Association for Reforestation of Tropical Forest (RETROF) organized by Japanese Forestry Agency. 相似文献
169.
170.
Kazumasa Ohta Kazuhiko Hoshizaki Katsunori Nakamura Akihiko Nagaki Yoichi Ozawa Aoi Nikkeshi Akifumi Makita Kazumi Kobayashi Osamu Nakakita 《Journal of Forest Research》2012,17(4):360-368
During the last few decades, pine wilt disease has spread to cool-climate regions in Japan and, more recently, the potential risk of it spreading into the European midwest has also become a concern. In a coastal pine stand (84.7?ha) in Akita, near the northern limit of pine wilt disease in Japan, we investigated seasonal variations in the incidence of damage caused by the disease to trees and oviposition by the disease’s insect vector, Monochamus alternatus, during a two-year period. Foliage discoloration occurred throughout each year, and its seasonal variation showed a bimodal pattern in Pinus thunbergii (a higher peak in May–June and a smaller peak in October) and a clear peak in June in P. densiflora, which differed from the patterns in seasonal variation seen for warm-climate regions. Oviposition scars by M. alternatus were found in 40–45% of the trees damaged each year. The percentage of trees that had oviposition scars was higher in P. thunbergii than in P. densiflora. This appeared to reflect the difference in seasonal discoloration pattern between the two species. Analysis of the oviposition risk showed that trees that exhibited discoloration starting between July and October had a significantly higher risk or significantly higher oviposition scar densities, particularly for those that became discolored between August and September (2.5–14.6-fold higher risk than during other months). Oviposition scar densities per damaged tree were similar within the period of higher oviposition risk. Considering both oviposition risks and scar densities, we concluded that trees with discoloration that become apparent between July and October are important targets for preventing the spread of pine wilt disease in Akita. 相似文献