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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：えひめ地域政策研究センター  

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記述言語：日本語   出版者・発行元：日本森林学会  

林業体験活動は、狭義には森林を育成して木材を生産する林業の諸作業を体験する活動であり、林業普及活動として取り組まれてきた面がある。一方で、野外教育や環境教育の一環として取り組まれる例もあり、林業体験活動には教育活動として幅広い可能性があると考えられる。本研究は、林業体験活動の一典型である間伐体験活動の構造を明らかにし、森林教育における林業体験活動の意味をとらえ直すことを目的とした。2002～2011年に行われた6事例のビデオ記録を分析した結果、以下のことが明らかになった。間伐体験活動の中核である伐倒作業では、22本が1～8人により5分1秒～29分33秒かけて伐倒されていた。間伐体験活動全体の基本構造は［往路－説明－準備－伐倒－玉切り－搬出－帰路］であったが、切り捨て間伐として玉切りと搬出を省略した例、玉切りに代え円板を採取した例、搬出後に間伐材の利用活動を行った例など、活動全体の規模や内容の調整が行われていた。活動の各部分においては、体験者と指導者や体験仲間との間に支援や協力関係がみられた。体験者の間伐対象木に対する態度は一般に攻略的であったが、樹木の生命を意識し苦悩する例もみられた。

DOI： 10.11519/jfsc.124.0.264.0

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：一般社団法人日本森林学会  

DOI： 10.11519/jjsk.63.0_34

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記述言語：日本語   出版者・発行元：CIEC  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：TREE-RING SOCIETY  

Radial growth characteristics of a high-elevation shrub species, sea buckthorn (Hippophae rhamnoides), were investigated at four sites in a river valley at altitudes ranging from 3,333 to 3,820 to a.s.l. close to the terminus of the July First Glacier in the western Qilian Mountains of northwestern China. Radial growth of the sea buckthorn was significantly and positively correlated with the mean monthly temperature in June of the current growing season. Based on the fact that fluctuations in the shrub's radial growth and the glacier's equilibrium-line attitude (ELA) are affected by climatic variables, a tree-ring width chronology of the four sites was used to reconstruct the ELA from 1950 to 2003. The resulting ELA model explained more than 55.3% of the variance in the ELA of the July First Glacier series. On a decadal time scale, the cumulative-departure curve of the reconstructed ELA series showed an increasing trend from the 1950s to the mid-1960s, followed by a descending trend from the mid-1960s to the mid-1970s. The FLA appears to have remained stable from the mid-1970s to the mid-1990s, but has displayed dramatic variations during the past decade.

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記述言語：日本語   出版者・発行元：日本森林技術協会  

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記述言語：日本語   出版者・発行元：北海道大学  

樹木年輪による気候復元は、高い時間分解能と適用範囲の広域性を特徴とする。樹木年輪気候学は、これまで多くの課題を克服しながら、現在も年輪データ時系列を過去に伸ばすことや解析対象地域を広げることをあわせて、気候に敏感に応答する年輪指標の解析が進められ、成果をあげている。本報告では、樹木年輪気候学が持ち合わせる長所と短所について整理するとともに、特に環オホーツク地域の樹木年輪気候学についての課題を提示し、同地域の古気候復元の可能性について述べる。

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：日本雨水資源化システム学会  

The impact of forest thinning operations on surface soil physical properties was investigated under varying forest conditions. Five forest conditions were delineated into natural broadleaved forest, Japanese cedar (Sugi) and Japanese cypress (Hinoki) plantations with and without thinning operations. Ordination analysis by principal component method of the different soil physical characteristics extracted two main components regarded as water holding factor (WHF) and water movement factor (WMF). The extracted principal component (PC) values were used as dependent variables to analyze the effects of forest species and forest operations. The results showed that both means of WHF and WMF were high in natural broadleaved forest and coniferous forest plantations with operations, and low in coniferous forests plantations without operations. Overall, the highest means of WHF were found in plantations occupied by cedar with operations comparable to natural broadleaved species. Moreover, the highest means of WMF were found in cypress plantations with operations and in broadleaved species whereas cedar and cypress plantation forests without operations showed the lowest values. These results suggest that the thinning operations indirectly contribute to improve surface soil physical properties of coniferous forest plantations.

DOI： 10.7132/jrcsa.KJ00004364697

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

The climate of western Nepal was reconstructed for the past 249 years using ring width and wood density of Abies spectabilis (D. Don) Spach from western Nepal. A total of 46 increment core samples were collected from 23 individual trees growing in an open A. spectabilis stand near timberline of 3850 m a.s.l. in Humla District, western Nepal. The core samples were subjected to densitometric analysis to obtain chronologies of ring width and three kinds of intra-annual bulk densities, i.e., minimum, maximum, and mean. Response analysis of tree-ring parameters with climate records revealed that the ring width was correlated negatively with March-May (pre-monsoon) temperature and positively with March-May precipitation, while the minimum density was correlated positively with March-July temperature and negatively with March-May precipitation. On the other hand, the maximum and mean densities were positively correlated with August-September and March-September temperatures, respectively. These results indicate that the ring width and minimum density are primarily controlled by the pre-monsoon temperature and precipitation, while the latewood density by the late monsoon temperature. Finally based on these results of the response analysis, a transfer function was established, with which March-September temperature was reconstructed for the past 249 years, which shows a warming trend from 1750s until approximately 1790, followed by cooling until 1810, then by a gradual warming trend extending to 1950, and a notable cold period continuing up to the present. No evidence of a consistent warming trend over the last century or two commonly appearing in higher latitudes was found in the present reconstruction, but possible factor behind the widespread glacial retreat in the Nepal Himalayas was discussed. © 2005 Elsevier GmbH. All rights reserved.

DOI： 10.1016/j.dendro.2005.08.003

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：愛媛大学農学部附属演習林  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：KLUWER ACADEMIC PUBL  

We present a warm season (April-September) temperature reconstruction for Asahikawa, north central Hokkaido, Japan for AD 1557-1990. The reconstruction, which accounts for 34% of the temperature variance from 1925-1990, is based on maximum latewood density data from Saghalin spruce (Picea glehnii) growing at timberline (1340-1390 m) at Mount Asahidake, Hokkaido. We only present a high frequency (prewhitened or white noise) version of the reconstruction because there is an unexplained offset in the mean between the actual and estimated temperature data for an earlier period of overlap from 1891-1924. The coldest summer in the reconstruction is 1718, for which the estimated value is 12.89 degrees C, nearly four standard deviations (SD) below the mean. A colder-than-average year is reconstructed for 1641 (13.30 degrees C, nearly 3 SD below mean), following the eruption of Komagatake, Hokkaido which began in July, 1640. The Asahikawa density chronology, shows decadal modes of variation with statistically significant spectral peaks prior to around 1850. A tree-ring width chronology for this same site (AD 1532-1990) is in phase with a tree-ring width record from central Kamchatka prior to around 1850, but out of phase since that time. This pattern suggests, as has been hypothesized for temperature-sensitive tree-ring records from the eastern Pacific sector (Alaska and Patagonia), that a decadal mode of climate variation was more dominant in the Pacific sector prior to about 1850, after which a higher frequency (ENSO-type) mode may have become more pronounced, at least until recent decades. Additional data from the northwestern Pacific is needed to compare to these findings.

DOI： 10.1023/A:1013085624162

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SPRINGER VERLAG  

An investigation was made of the effects of tracheid dimensions on variations in the maximum density of Picea glehnii Mast., which were associated with climatic changes. Radial cell diameter and the thickness of the tangential cell walls of the last-formed cells in 90 annual rings of nine trees with different annual ring widths were analyzed by image analysis. Correlations between maximum density and tracheid dimensions indicated that changes in maximum density were due mainly to changes in cell wall thickness of the last-formed cells in annual rings and were not due to changes in radial cell diameter. The effects of climatic factors on tracheid dimensions were examined by application of dendroclimatological techniques. A chronology of cell wall thickness that represented common signals among trees was established. Simple correlation and response function analyses of the chronology revealed that cell wall thickness was influenced positively by summer temperature and negatively by precipitation in August, and these responses were similar to those of maximum density. The study demonstrated that variations in maximum density were due to variations in the cell wall thickness of the last-formed cells, which varied depending on the weather in summer.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER  

The responses to climatic and nonclimatic factors of Yezo spruce (Picea jezoensis Carr) trees growing in a natural forest in Tomakomai, Hokkaido were analyzed by dendrochronological methods. The effects of climatic factors were examined by response function analysis. More than 70 % of the variance of ring-width and maximum-density indices was explained by climatic data from 1924 to 1965. The effect of nonclimatic factors on radial growth from 1966 to 1990 was analyzed by comparing actual indices with the estimated indices of ring width and maximum density calculated from the climatic data. Actual ring-width indices were lower than the estimated indices every year from 1969 to 1977. Actual maximum-density indices were lower than the estimated indices every year from 1971 to 1974. These results indicate that some nonclimatic factors might have affected both ring width and maximum density in the 1970s. ((C) Inra/Elsevier, Paris.).

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SPRINGER VERLAG  

Increments in the radii of Norway spruce (Picea abies Karst.) and Yezo spruce (Picea jezoensis Carr.) trees that revealed symptoms of a decline in growth were analyzed by dendrochronological methods in an attempt to correlate past reductions in growth with their main causes. The trees were growing at different sites near the industrial district of Tomakomai, Hokkaido. A skeleton plot method was used to construct a series of pointer years that revealed the number of trees with a clear reduction in growth or recovery from such a reduction. An analysis of ''abrupt growth changes'' demonstrated that at least two periods of growth reduction were common to a large number of Norway spruce trees. The reduction events were related to the records of industrial activity near the forest and meteorological data. The growth reduction in the 1970s coincided with the start of operation of certain local factories, and its extent was related to the distance from the industrial region. By contrast, a reduction in growth in 1984 was detected at all the Norway spruce sites and the extent was approximately the same at all sites. This phenomenon was related to extreme drought conditions. Growth of Yezo spruce trees was less sensitive to industrial activity and to drought than that of Norway spruce. Thus, differences in response to air pollution and drought were observed between the two species.

DOI： 10.1007/s004680050075

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPAN WOOD RES SOC  

The effects of climatic and nonclimatic factors on the radial growth of non-vital Norway spruce (Picea abies Karst.) trees were evaluated by the application of a dendrochronological technique. Trees growing near the industrial district in Tomakomai, Hokkaido, Japan, exhibit symptoms of forest decline, namely, needle loss and standing death. Nonclimatic variations in ring widths were evaluated by comparing actual and estimated ring-width indices that had been reconstructed from climatic factors. The trees at sites near the industrial district showed extreme reductions in actual ring-width indices from 1970 to 1971 as compared with the estimated ring-width indices. This discrepancy coincided with the period when most of the factories in the industrial district started operations. Therefore, it is proposed that the difference between the actual and estimated ring-width indices from 1970 to 1971 is a consequence of nonclimatic stress factors, such as air pollution.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Canadian Science Publishing  

The influence of climate on the radial growth of Japanese ash (Fraxinus mandshurica Rupr. var. japonica Maxim.) in northern Hokkaido, Japan, was investigated. Fifteen trees were selected and ring widths were measured. Standardization and autoregressive modeling were applied to the series of ring widths for isolation of the climatic signal. A response function was calculated for the relationship between residual chronology and monthly temperature and precipitation. In the season that preceded the growth, December precipitation is negatively correlated with ring width. During the growing season, May temperature is negatively correlated with ring width, while both temperature and precipitation in July are positively correlated with ring width. The results reveal the potential usefulness of Japanese ash for reconstruction of past climate in Hokkaido. The chronology of Japanese ash contributes to a development of a tree-ring network in Japan that is still sparse.

DOI： 10.1139/x26-231

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記述言語：日本語   出版者・発行元：北海道大学  

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記述言語：日本語   出版者・発行元：北海道大学  

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J-GLOBAL

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記述言語：日本語   出版者・発行元：北海道大学農学部演習林  

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記述言語：日本語   出版者・発行元：日本森林学会  

DOI： 10.11519/jfsc.123.0.G01.0

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記述言語：日本語   出版者・発行元：日本森林学会  

DOI： 10.11519/jfsc.122.0.360.0

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記述言語：日本語   出版者・発行元：日本森林学会  

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記述言語：日本語   出版者・発行元：日本森林学会  

DOI： 10.11519/jfsc.120.0.392.0

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記述言語：日本語   出版者・発行元：日本森林学会  

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記述言語：日本語   出版者・発行元：一般社団法人日本科学教育学会  

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記述言語：日本語   出版者・発行元：日本森林学会  

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記述言語：日本語   出版者・発行元：日本森林学会  

DOI： 10.11519/jfsc.118.0.13.0

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記述言語：日本語  

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記述言語：日本語  

J-GLOBAL

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記述言語：日本語  

J-GLOBAL

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記述言語：日本語  

J-GLOBAL

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記述言語：日本語  

J-GLOBAL

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記述言語：日本語  

J-GLOBAL

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記述言語：日本語  

J-GLOBAL

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記述言語：日本語  

J-GLOBAL

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記述言語：日本語  

J-GLOBAL

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