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本研究は，近年増加傾向にある野生動物との衝突による鉄道の「輸送障害」について，東日本における実態を把握すると同時に，特に発生件数の多いJR東海の身延線を事例に多発区間を特定し，その環境および対策と課題を考察したものである。「輸送障害」は，2020年12月から2021年11月の1年間に発生した障害の詳細を，JR東海の公式Twitter運行情報より集計し，分析した。その結果，以下のことが明らかになった。1）JR北海道管内では，特に宗谷本線，花咲線などでエゾジカやヒグマとの衝突が，JR東日本管内の東北エリアでは山田線で，関東甲信越エリアでは中央本線で，JR東海管内では身延線で，シカとの衝突件数が突出して多い。2）身延線では，1年間に215件の衝突が発生しており，特に10～11月に集中している。区間別では，内船駅～甲斐大島駅間で最も発生件数が多いが，ここは山麓斜面と富士川に挟まれた険しい地形の森林に覆われた区間であった。シカとの衝突は，季節性と地域性が認められた。3）身延線の運行情報から運転見合わせ時間を推計した結果，1件平均約35分の遅延が発生しており，これは全線で年間約5日間列車が止まっている計算になる。4）野生動物との衝突回避対策として，シカの忌避音発生装置の設置，徐行区間の設置，侵入防止柵の設置，「鹿マット」の設置などが行われている。5）シカは，鉄分補給のためレールを舐めに線路内に侵入することがわかってきた。そのため，線路以外の場所に鉄分を含む固形の誘鹿剤を置き，シカを誘導する方策が，シカ侵入対策，「輸送障害」への新たな対策として期待されている。

尾瀬ヶ原は日本最大の高山泥炭湿原であり，貴重な泥炭生態系として保全されてきた．しかし20世紀後期からニホンジカの侵入と豪雨による洪水による生態系の攪乱が顕在化してきた．本稿では二酸化炭素（CO2）やメタン（CH4）放出に関する既往の研究と尾瀬ヶ原湿原におけるニホンジカの攪乱が及ぼす影響を概観する．尾瀬ヶ原，中田代の5か所，14地点で2019年6～10月の5か月間に土壌およびガス試料を採取・分析した．攪乱によるアンモニア態窒素の増加が認められた．非攪乱地のCO2やCH4放出は8月に極大が見られ攪乱地より多かった．CO2やCH4放出量は地下水位と負の相関関係が見られ，尾瀬ヶ原におけるニホンジカの攪乱が地下水位と泥炭土壌の理化学性および温室効果ガスの放出に顕著な影響を及ぼしていることが示された．, Ozegahara mire is the largest alpine mire in Japan. The mire has been preserved as a precious peatland ecosystem with high ecological diversity. After the late 20th century, the mire has been exposed to ecosystem disturbance by mire flooding due to heavy rain as well as invasive Sika deer. This manuscript reviewed studies about greenhouse gas emission from wetland and report the effects of Sika deer disturbance on the soil physicochemical properties and the emission of carbon dioxide (CO2) and methane (CH4) from Ozegahara mire. Soil and gas samples were collected at fixed 14 fixed plots on 5 sites with and without mire disturbance by Sika deer in Naka-tashiro of Ozegahara mire through 5 months of 2019 (June to October), and determined their properties and gas composition each month. Groundwater level displayed similar seasonal change in two sites, being affected by precipitation. The concentrations of NH4+ nitrogen in the disturbed sites were higher than those in the undisturbed sites. Mechanical disturbance of the peat soils by deer resulted in mineralization of organic matter. CO2 and CH4 fluxes from the undisturbed sites were highest in August, and those were higher than those from the disturbed sites. Negative correlation was found between CO2 and groundwater level and also correlation between CH4 and groundwater level was negative, suggesting the importance of groundwater level in greenhouse gases flux, depending on the sites and also species of greenhouse gases.

国内で流通しているシカおよびイノシシ肉の品質向上のために，処理施設より胸・腰最長筋を購入して，熟成終了時のpHを測定し変動要因について調べた．調査票から動物種，性別，体重，捕獲方法（箱わな，囲いわな，足わな）を要因とし分散分析により解析した．また，タンパク質の変性程度を測定しPale, Soft, and Exudative (PSE)の発生についても調査した．その結果，調査個体の35％はDark, Firm, and Dry (DFD)が疑われるpH>6.0であり，足わなによる捕獲がpHを有意に高くし，オスがメスより高くなる傾向が認められた．一方，PSEと判定されたのは箱わなおよび囲いわなで捕獲された頭数の52%，足わな捕獲の5.8％であった．以上の結果より，品質の高い野生獣肉を提供するには早期発見によるDFDの回避と，興奮を抑えた止め刺し技術によるPSE回避が重要であることが示された．

シカによる森林被害が拡大する中で，有害鳥獣捕獲報奨金を中心とした行政施策が強化されている。捕獲数を増やし個体数を管理するためには地元猟友会の協力が不可欠である。しかし，捕獲方法の開発や改良が進む一方で，猟友会に所属する狩猟者の就業構造や狩猟慣習の変化を踏まえた狩猟者数の増加対策に関する研究は遅れている。本報告は伝統的な狩猟が継承されてきた宮崎県椎葉村大河内地区を対象に，猟友会メンバーへのインタビューを行い，年齢別に就業構造の特徴および生活における狩猟の位置づけの変化，個体数管理のための捕獲と伝統的な狩猟の違いを考察した。その結果，51 歳以上の狩猟者は学卒後に大河内地区内で就業し，狩猟経験が豊富であるが，41 歳未満はU ターンで地区外勤務であり狩猟経験が少ないこと，捕獲頭数に応じた報奨金は一部のベテラン狩猟者にとっては経済的な意味を有しているものの，捕獲だけを目的とした夏の狩猟と楽しみで行う冬の狩猟では狩猟の意味合い違うことなどが明らかとなった。若手狩猟者の技術向上のために捕獲従事日数に応じた報奨金制度を導入すること, 更に椎葉村で増加傾向にある移住者を含む住民を対象に狩猟免許取得の支援などが必要であることを示唆した。, As damage of forest degradation by Sika deer browsing is on the rise, the government has attempted to strengthen their schemeof monetary reward for capture. The support of local hunter organizations is crucial for increasing capture numbers and controllingthe deer population. However, there is less/no research to increase the number of hunters, based on the employment structures ofthe hunting organizations, and the change in hunting traditions, although the capture methods have developed and improved. Byinterviewing members of an organization in Ookawauchi area, Shiiba Village, Miyazaki Prefecture where traditional hunting remainsvery much alive, this research paper examined the following: the characteristics of the employment structure based on age and changesof the role of hunting in members’ lives, as well as the differences between hunting for controlling the population and traditionalhunting. The findings were as follows. Hunters, who are 51 years old or more, worked in the Ookawauchi area after final school yearand have considerable hunting experiences. However, hunters under 41 years old worked outside the area once before coming backand have little experiences. Moreover, whilst the monetary reward based on the number of hunted animal is financially important forsome well-trained hunters, the purpose of hunting varies by season; summer hunting is only for capturing deer, whereas winter huntingis for recreation. To improve young hunters’ skills, the monetary reward based on days engaged in hunting should be introduced. Andto increase the number of hunters, support needed to obtain hunting licenses for residents, including to the growing number of newresidents in Shiiba Village who have moved in recent years, were suggested.

We compared the effects of tree size and the basal area of neighboring trees on the growth rate and mortality of individual trees over the past 30 years (1984-2014), before and after the increase of a sika deer population in a mixed conifer-broadleaf forest in the Shiiba Research Forest of Kyushu University in Japan. In the study site, sika deer (Cervus nippon) have reduced understory vegetation since the 1990s, denuding it since the 2000s. Most of the recruitment in the second half of the study period (1996–2014) consisted of tree species that sika deer cannot consume, such as Illicium anisatum and Pieris japonica subsp. japonica. Smaller trees had higher mortality throughout the study period. Neighboring trees affected the tree mortality significantly in the first half of the study period (1984–1996), while they did not significantly affect it in the second half. However, neighboring trees significantly affected the growth rate of trees throughout study period. Based on our findings, we speculate that an increase in sika deer population may have affected the competition between individual trees in the mixed forest. The effects of tree size and neighboring trees on mortality and growth varied depending on the growth form groups and the species., 九州大学農学部附属宮崎演習林内の針広混交林において，樹木サイズと隣接個体の胸高断面積合計が樹木の成長と枯死に及ぼす影響を，シカの個体数が増加した30 年間の前期（1984-1996 年）と後期（1996-2014 年）とで比較した。本調査地では下層植生が1990 年代から衰退し，2000 年代ではほぼ消滅した。調査期間の後期に更新した樹木のほとんどは，シカが採食しないシキミとアセビであった。小径木は成長速度が遅く，枯死率が高い傾向が調査期間を通じて観察された。調査期間の前期では，隣接個体が枯死率に有意に影響を及ぼしていたが，後期では影響が見られなかった。一方，隣接個体の成長に及ぼす影響は調査期間を通じて観察された。以上の結果から，本調査地において，シカの個体数増加は樹木の個体間競争に影響を及ぼした可能性が示唆された。これらの影響は樹木の生活型や種によって異なっていた。

九州大学宮崎演習林内の冷温帯針広混交林に1971年に設定した調査地を2013年に復元し，森林構造と種組成を再調査した。1971年に林床を被覆していたスズタケは2013年には完全に消失した。その他の下層の木本も，シカが摂食しないシキミとアセビ以外は消失した。樹高2m 以上の木本も種数，幹数とも大きく減少した。特に胸高直径5cm 未満の木本は幹数が20%程度まで減少した。胸高直径５cm 以上の針葉樹は，同サイズの広葉樹よりも成長速度が速かった。死亡率は落葉広葉樹が常緑針葉樹や常緑広葉樹よりも低かった。モミはツガよりも成長速度が速く，死亡率が高かった。モミの優占度はツガよりも大きかったが，今後はツガの優占度が増加するかもしれない。しかし，シキミとアセビ以外の新規加入がみられないため，さらに長期的にはシキミとアセビが優占する林分になる可能性がある。, In 2013, we reestablished study plots established in1971 in a cool temperate mixed forest in the Shiiba Research Forest, Kyushu University. We identified the trees measured in the former study, and measured stand structure and species composition again. The understory had mostly been denuded by sika deer browsing in 2013, while Sasa borealis covered the forest floor thickly in 1971. The number of species and stems of trees taller than 2m in height also decreased largely. Especially, the stem numbers of trees smaller than 5cm in diameter at breast height (DBH) decreased up to 20%. The growth rate of conifer larger than or equal to 5cm in DBH was larger than those of broad-leaved trees. The mortality of deciduous trees was smaller than those of evergreen trees. The larger growth rate of Abies firma corresponded to the larger dominance of A. firma than Tsuga sieboldii. The low mortality of T. sieboldii suggested that the dominance of T. sieboldii would increase in the future. Further, the stand would be dominated by two species sika deer cannot consume, Illicium anisatum and Pieris japonica subsp. japonica, because no species other than the two species regenerated in the stands.

北海道におけるエゾシカ検査モデルにおいて，獣医師による解体時検査の実施されたエゾシカ368例のうち8例の肺に異常が確認された．このうち7例では，肉眼的に孤在性から多発性の硬結感のある結節性病変が認められ，組織学的にはアスペルギルス様真菌を伴う乾酪化肉芽腫もしくは乾酪壊死巣が認められた．うち3例については分子生物学的にAspergillus fumigatusと同定された．以上から，7例は肺アスペルギルス症と診断された．シカの肺病変に占める割合の高さと病変の重篤化の点から，アスペルギルス症はシカの肺における重要な疾患であると考えられた．容易に触知できる病変を形成するため，解体時検査における触診検査が重要であり，個体の健康状態の把握のためにも適切な内臓検査の実施が不可欠であると考えられる．, In the Hokkaido venison inspection project, veterinary inspectors examined 368 deer and found that 8 had pulmonary abnormalities. The affected deer were captured and fed until they were slaughtered. In 7 of the 8 cases, the lesions were single or multiple firm nodules located in the lung parenchyma, and were histologically characterized by a combination of caseous granuloma or caseous necrosis and intralesional Aspergillus-like fungi. In 3 of the 7 cases, the fungi were identified as Aspergillus fumigatus using molecular biological methods. Accordingly, the 7 deer were diagnosed with pulmonary aspergillosis. Based on its frequency among the detected pulmonary lesions and the severity of the advanced cases, it was concluded that aspergillosis is a significant lung disease in deer. Pulmonary aspergillosis lesions can be readily palpated during manual inspections, and appropriate visceral examinations including palpation are necessary to determine the health status of deer for venison.

ニホンジカの影響を大きく受けている世界遺産春日山原始林および春日野一帯はかつてどのような植生景観であり,今に至っているのだろうか。千年以上にわたる自然史を紐解くヒントが,700年代に描かれた最古の地図,鎌倉時代から室町時代に描かれた春日曼荼羅および春日権現験記などに代表される絵図にあると考えられる。本報では,日本最古の地図「東大寺山堺四至図」および鎌倉時代の春日曼荼羅などの絵図から,春日山およびその周辺の植生景観を読み取り,考察した。, I studied ancient Mount Kasuga and its surrounding landscape and vegetation using the oldest known map of the area, drawn in 756 (`Todaiji Sankai Shiishi Zu'), and cultural artifacts such as the Kasuga mandalas from the Kamakura period and the Illustrated Tales of the Miracles of the Kasuga Deity (`Kasuga Gongen Kenki'). One Kasuga Shrine mandala(the`Kasuga Miya Mandala') depicts Mount Mikasa, the abode of the Kasuga deity in front of Mount Kasuga, with a bird's-eye view of the landscape. Other images on Kasuga mandalas include a spring scene of Kasugano with cherry blossoms and willows, and an autumn scene with many deer. These are likely to be connected to the landscape of Kasugayama, a warm temperate evergreen forest, and Nara Park, which still contains deer. The winter scene of Mount Kasuga in `Kasuga Gongen Kenki' clearly indicates that the forest consisted mainly of evergreen broad-leaved trees, and contained some deciduous broad-leaved trees and conifers. The deer mandala depicts the image of the sacred tree(`sakaki': Cleyera japonica) behind a deer, symbolically reflecting the presence of the god (`kami'). The image titled Kasuga Deities Departing from Kashima Shrine(`Kashimadachi Shin'ei Zu') also shows vegetation and gods and the presence of sacred deer. I propose that the plant in this image may be Podocarpus nagi, which was respectfully presented to the Kasuga Shrine (`Kasuga Taisha') by other prefectures in the Middle Ages. This is supported by plant morphology and the presence of P. nagi on Mount Mikasa. This study suggests that today's Mount Kasuga and the surrounding Kasuga Field retain the cultural landscapes of the Middle Ages.

This paper discusses the structure and the interpretation of an indeterminate in Japanese followed by a particle mo (henceforth, indet-mo) by carefully examining the interpretation of sika 'only'. X sika V nai, such as (87a), is known as yielding a contrastive implication as in (87b), in addition to its (more or less) straightforward meaning as in (87c). (87) a. Taro sika hon wo kaw-anak-atta. Taro only books acc buy-neg-past. b. Taro bought books. c. Everyone excluding Taro didn’t buy books. What is remarkable is the fact that an indet-mo has a universal interpretation when an indet-mo precedes sika, as in (88a), while it carries an existential interpretation when sika precedes an indet-mo, as in (88b). (88) a. Daremo John sika mi-nak-atta. (SOV) indet-mo John only see-neg-past 'All the people saw John, and they didn't saw anyone other than John.' b. John sika daremo mi-nak-atta. (OSV) John only indet-mo see-neg-past 'Someone saw John, and nobody saw the people other than John.' This paper proposes that the two-way interpretation of an indet-mo shown in (88) results from the two structural positions that an indet-mo can occur in: an indet-mo itself denotes an indefinite group of people/ things and (i) when it is in the subject position of a predication, it yields a universal interpretation as a result, while (ii) when it is in the argument position of a negative predicate, it corresponds to an existential interpretation because of the fact that it serves as a target of negation.

The Shuri Castle and neighboring sites such as the Tenkai Temple often yield the remains of Shika deer, which is not native to the Okinawa islands. Based on comparative studies with modern deer specimens, Shika deer bones recovered from the region belong to Cervus nippon. Furthermore, it is possible to further classify them into subspecies by measuring the size of the bones. The smaller are C. nippon keramae, C. nippon yakushimae, and C. nippon mageshimae; the larger ones are C. nippon pulchellus, C. nippon nippon, C. nippon centralis and C. nippon yesoensis. The analysis of these bones shed light on the external relationship of the Ryukyu Kingdom. The analysis indicates that C. nippon was brought to the Okinawa Islands several times. One of the reasons that Shika deer were imported was for consumption as indicated by the presence of cut marks. Ryukyu-koku-yurai-ki (the genesis of the Ryukyu Kingdom), describes that in the early 17th century deer were carried from Satuma into Ryukyu. Additionally some documents record that venison was one of the menu items with which the king regaled Chinese envoys. Thus the existence of C. nippon remains from Shuri and Tenkai Temple evidences some form of relationship among Ryukyu, China, and Japan.

Fat contents of femur marrow by dry weight method and Riney's kidney fat index were assessed from 147 carcasses of sika deer dead in and around Nara park, Nara prefecture, central Japan. Femur marrow was categorized into five by color and texture, and these were arranged three by fat contents, such as malnutrition, ordinary and healthy. This classification is available for the management of Nara deer.

ニホンジカ(Cervus nippon)の採食による植生変化が近年目立つようになった京都大学芦生研究林において, 2002年から2003年にかけて, ニホンジカの採食とササ群落の衰退の関係を調査した.糞分析を行い, ニホンジカの餌資源としてのササの重要性を調べた.また, シカによる葉の被食, 稈の枯死の程度を調べ.地形条件との関係を調べた.さらに, 積雪期に踏査を行い, ササの衰退と積雪分布の関係を調べた.シカの糞内容物に占めるササの割合は年間を通じて20～50%であり, 特に冬期に高かった(54.12 ± 16.73%).ササの葉の被食と稈の枯死は, 緩傾斜, 高標高, 尾根部において多かった.また, 積雪が少なく融雪が早い地点でササ群落の衰退が進み, 積雪が多く融雪の遅い地点で衰退の程度が小さい傾向が見られた.以上より, シカの採食によるササ群落の衰退地の分布は地形条件と積雪分布に強く影響を受けることが示唆された.その背景には, シカが緩傾斜の尾根部のような採食行動をとりやすい地形条件を選択してササ群落を採食すること, 特にシカにとってササが重要である積雪期には, 積雪の少ない地点を集中的に採食することが考えられた., Recently, the effects of Sika deer (Cervus nippon) grazing have changed vegetation in Ashiu Research Forest Station, Kyoto in western Japan. In this forest, we studied the relationships between Sika deer grazing and the decline of Sasa spp. distribution from 2002 to 2003. We investigated the food habits of Sika deer by fecal analysis method. We surveyed the relationships between the terrain attributes and the ratio of eaten Sasa leaves and dead culms, and the relationships between snow distribution and the decline in Sasa spp. distribution. The fecal analysis showed that the proportion of Sasa in the feces was great all year round and was highest during winter (54.12 ± 16.73%). This indicates that Sasa was an important food plant for Sika deer, particularly during winter. Heavy grazing of Sasa leaves and dead culms were observed in the gentle terrain at high elevation or on ridges. Further, Sasa decline was more marked at shallow snow places than deep snow places. We concluded that decline of Sasa was caused by Sika deer grazing and that grazing intensity on each community was strongly affected by topography and by the snow depth., 特集 : ニホンジカの森林生態系へのインパクト: 芦生研究林

シカによる森林下層植生の喪失が森林生態系の物質循環に与える影響を明らかにするため, 京都大学芦生研究林内で防鹿柵を設置したU谷と設置しなかったK谷の各集水域末端と各集水域内の支流から5ヶ所ずつ渓流水を採取し, 水質を測定した.集水域面積が3ha未満の小集水域間では渓流水質が有意に異なったことから, 水質形成要因が空間的に不均一であることが示唆された.一方, 10ha以上の面積を持つ集水域末端では水質に差が認められず.集水域全体での水質形成機構はおおむね等しいものと考えられた.また, 柵設置後1年では渓流水質に変化が見られなかった.防鹿柵設置後の下層植生の回復は時空間的に不均一かつ漸次的であることが推測され, 集水域末端だけでなく水質形成要因の空間的不均一性を考慮できる小集水域も対象とした観測が望まれる.本調査地において小集水域を含んだ継続調査を行うことにより.シカの食害が生態系機能全体に及ぼす影響を解明できることが期待される., Currently, the decrease of forest understorey by Japanese deer overbrowsing is widely reported in Japan. In order to clarify the influences of the understorey disturbances by deer on nutrient cycling in forest ecosystem, we examined streamwater chemistry in the U watershed, where deer exclusion fence was installed over all, and in the unfenced K watershed. One outlet and four sub-catchments within each watershed were used. The wide variability of streamwater chemistry was observed among sub-catchments of both watersheds, while no significant difference was detected between both outlets. This indicates that by using not only outlets, but also the small sub-catchments within the watersheds in our study sites, we can evaluate the spatial heterogeneity of streamwater chemistry, so the effects of spatio-temporally heterogeneous and gradual recovery of understorey vegetations after deer exclusion can be expectedly comprehended in more details. The results also indicate that throughout one year since the fence installation, there has been no effect of deer exclusion on streamwater chemistry yet. Continuous observation is needed to clarify the effects of deer overbrowsing on forest ecosystem functioning and the definite impacts of atmospheric depositions to nutrient cycling in our study sites, where the watershed design is convenient for clearly demonstrating them., 特集 : ニホンジカの森林生態系へのインパクト: 芦生研究林

Kidney fat and concentration of femur and mandible marrow fat on the sika deer, Cervus nippon, coltected in Shizuoka prefecture were analyzed. Both the femur marrow fat (FMF) and mandible marrow fat (MMF) were kept more than 50% under the condition of more than 20% on Riney's kidney fat index (RKFI), and decreased under the condition of less than 20% on RKFI. There were significant inverse correlations between fat and water concentration in both the femur and mandible (r2 = 0.934 and r2 = 0.807). Dry-weight method in the femur and mandible marrow is available for the estimation of FMF and MMF. We recomend using the mandible for the management of deer population because of easy collection from hunters.

広域で設置される獣害防止柵では道路や河川などと交わる場所に柵のない開口部が生じる。本研究ではニホンジカの高密度生息地域である神奈川県丹沢山系に設置された広域獣害防止柵(52km)を対象に,開口部の存在がシカ侵入防止に及ぼす影響について調査した。開口部は2.0箇所/kmの割合で存在しており,道路と河川による開口部が多くほぼ同数(各0.8箇所/km)を占めた。開口部のシカ通過頻度は,開口部幅3.0m以下で有意に低くなった。広域柵には倒木や野生動物の働きによって生じた破損開口部も存在したが,野生動物由来の破損部を通過するシカは少なかった。柵の山側から農地に侵入してくるシカは,開口部1箇所あたり0.24頭/日と推定された。山から里への移動は日没後に,里から山への移動は早朝に活発となった。すなわち,農地への侵入は夜間に行われており,侵入したシカは柵から最遠2kmの農地にまで侵入していた。しかし日没後と早朝に開口部を逆方向に通過する個体も少なからずみられ,それぞれ前者の37%および30%を占めた。これは昼間に人里側のヤブに潜む個体と考えられた。獣害防止のためには人里のヤブ刈り払いが重要といえる。, Regional wildlife control fences are often interrupted by roads and streams. To investigate the negative impacts of these openings for efficiency of fences, a sensor camera survey was conducted at a sika deer fence that was constructed along the foot of the Tanzawa Mountains in Kanagawa Prefecture over 52km. Openings were found at the ratio of about 2.0 per kilometer. The frequency of gaps by road and human trails was 0.8/km, and 0.8/km by streams. Passing frequency of the deer became low at narrow openings (

鹿児島大学

オオバアサガラ(Pterostyrax hispidus SIEB. et Zucc)は,シカの食害地において被害の少ない樹種の一つである。そこで,食害によって林床植生が消失した人工林の土壌流亡などを軽減する方法の一つとして,本種を林床植生に種子散布や植栽で導入する諸条件を検討した。試験地はカラマツ林,サワグルミ林を対象にし,それら試験地の下層木として成育する天然生オオバアサガラを対象に生育状況の異なる5プロットを設定した。その結果,林内相対照度が高いほどオオバアサガラの成立本数,平均樹高,平均根元直径,根元断面積合計のいずれも増大する傾向を示した。さらに,微地形的には凸地より凹地の方で,急斜面よりも緩斜面において生育は良好であった。 これらことからシカの林床植生食害が激しい人工林で本種の天然更新が可能な場所としては,種子供給源である母樹が近くにあり,林内相対照度が 20% 以上で,凹地の緩傾斜地が有力である。また,人工植栽する場合も,凹地形や平坦面に植栽し,林内相対照度に配慮する必要がある。, Pterostyrax hispidus, which is not consumed by sika deer, grows in regions that have experienced severe browsing damage. We examined whether introducing P. hispidus to managed forests with poor ground conditions would help preserve the forest floor. Investigation plots were established within a natural community of P. hispidus that grows within managed forests containing Larix kaempferi and Pterocarya rhoifolia . We found that the relative light intensity affected the stand density, height growth, basal diameter, and basal area of P. hispidus and that growth of P. hispidus was better under trees with concave, rather than convex, topography. These results suggest that natural regeneration was succeeding and that P. hispidus seeds will grow in target areas if the relative light intensity is equal to or more than 20% and the canopy topography is concave.