Warm-temperate Evergreen Broad-leaved Forest Research Articles

Predicting Suitable Restoration Areas for Warm-Temperate Evergreen Broad-Leaved Forests of the Islands of Jeollanamdo<sup>1a</sup>

Predicting Suitable Restoration Areas for Warm-Temperate Evergreen Broad-Leaved Forests of the Islands of Jeollanamdo<sup>1a</sup>

Oviposition site selection by Japanese gypsy moth (Lymatria dispar japonica) in a warm-temperate secondary forest in western Japan

The larvae of Japanese gypsy moth (JGM, Lymantria dispar japonica) are highly polyphagous and considered a serious pest that cause significant ecological and economic losses in forests. Monitoring of egg masses is important to prevent large outbreaks of JGM from occurring in their native range. To investigate oviposition site selection by JGM, we analyzed the occurrence and spatial distribution of egg masses across various evergreen tree species within a secondary forest dominated by evergreen broad-leaved trees in western Japan, following a large outbreak. Egg masses were concentrated on the abaxial surfaces of the leaves of a few evergreen tree species. There was a strong preference for Camellia japonica L., on which more than 75% of the egg masses were found. Egg masses were only found on evergreen tree species with large leaves (leaf area >10 cm2 and leaf dry mass >0.1 g). The spatial distribution of egg masses were clustered at scales around 1‒2 m. For effective monitoring of JGM egg masses in warm-temperate evergreen broad-leaved forests of Japan, the abaxial surfaces of the most abundant evergreen broadleaved trees with large leaves should be checked. If egg masses are found, it is likely that nearby trees of the same species will also have egg masses. Large trees should be checked thoroughly for occurrence of multiple egg masses.

Responses of microbial community to soil warming in warm-temperate evergreen broad-leaved forests

Responses of microbial community to soil warming in warm-temperate evergreen broad-leaved forests

Conservation of endangered ecosystem of warm-temperate evergreen broad-leaved forest (lucidophyllus forest) with local community : implementation of collaborative management in Aya Town, southern Kyushu, Japan

Conservation of endangered ecosystem of warm-temperate evergreen broad-leaved forest (lucidophyllus forest) with local community : implementation of collaborative management in Aya Town, southern Kyushu, Japan

Topography-specific emergence of fungal fruiting bodies in warm temperate evergreen broad-leaved forests on Yakushima Island, Japan

We conducted line route censuses of fungal fruiting bodies from August to September in 2005 and 2006 along ridges and valleys and compared the differences in the encounter rates of fungal fruiting bodies (= fruiting bodies seen per census kilometer) between types of topography and between fungal functional groups (i.e., ectomycorrhizal and saprobic fungi) in warm temperate evergreen broad-leaved forests on Yakushima Island, Japan. We found 251 fungal fruiting bodies (26 families, 50 genera, and 65 species) in total, including 51 bodies from Tricholomataceae, 41 from Russulaceae, 25 from Boletaceae, and 19 from Amanitaceae. The encounter rate of ectomycorrhizal fungi was greater at the ridge route (26.7unit/km) than at the valley route (8.7unit/km) and that of saprobic fungi was greater at the valley route (25.0unit/km) than at the ridge route (12.5unit/km). In addition, we conducted 7-year intermittent sampling and identified 40 families, 96 genera, and 142 species. The topography-specific emergence pattern of the intermittent sampling method was similar to that of the line census method. The fungal species composition in this study was possibly affected by a topographic gradient for both fungal functional groups through soil moisture, nutrient availability, and host tree distribution.

Topography-specific emergence of fungal fruiting bodies in warm temperate evergreen broad-leaved forests on Yakushima Island, Japan

We conducted line route censuses of fungal fruiting bodies from August to September in 2005 and 2006 along ridges and valleys and compared the differences in the encounter rates of fungal fruiting bodies (= fruiting bodies seen per census kilometer) between types of topography and between fungal functional groups (i.e., ectomycorrhizal and saprobic fungi) in warm temperate evergreen broad-leaved forests on Yakushima Island, Japan. We found 251 fungal fruiting bodies (26 families, 50 genera, and 65 species) in total, including 51 bodies from Tricholomataceae, 41 from Russulaceae, 25 from Boletaceae, and 19 from Amanitaceae. The encounter rate of ectomycorrhizal fungi was greater at the ridge route (26.7unit/km) than at the valley route (8.7unit/km) and that of saprobic fungi was greater at the valley route (25.0unit/km) than at the ridge route (12.5unit/km). In addition, we conducted 7-year intermittent sampling and identified 40 families, 96 genera, and 142 species. The topography-specific emergence pattern of the intermittent sampling method was similar to that of the line census method. The fungal species composition in this study was possibly affected by a topographic gradient for both fungal functional groups through soil moisture, nutrient availability, and host tree distribution.

Seedling establishment of five evergreen tree species in relation to topography, sika deer (Cervus nippon yakushimae) and soil surface environments

We investigated the seedling survival of five evergreen tree species over 3 years inside and outside deer-exclusion fences in a warm temperate evergreen broad-leaved forest on Yakushima Island, Japan. Seedling survival was examined in relation to topography, herbivory by sika deer, and the soil surface environment (i.e., soil surface wetness, light conditions, slope inclination, and soil disturbance). The study species included Myrsine seguinii Lév., Syzygium buxifolium Hook. et Arn. (Group A: species distributed on the upper slope of the study site), Litsea accuminata (Bl.) Kurata, Schefflera octophylla (Lour.) Harms (Group B: species distributed on the lower slope), and Cleyera japonica Thunb. p.p. emend. Sieb. et Zucc. (Group C: species distributed on both slopes). The soil surface environment on the upper slope was drier, lighter, and more easily disturbed than the lower slope. Generalized linear model analyses indicated that seedling survival in fenced and unfenced quadrats was greater on the upper slope than on the lower slope for Group A and B species but not for Group C species. A micro-spatial scale analysis revealed that seedling survival was correlated with soil wetness, ground light conditions, and soil disturbance but not slope inclination. These results indicate that seedling survival was correlated with topography, sika deer herbivory, and the micro-spatial scale environment. Topography-related differences in seedling survival appear to adequately reflect the observed adult plant distributions for Group A and C species but not for Group B species.

Impact of leaf physiology on gas exchange in a Japanese evergreen broad-leaved forest

We used a multi-layer model to analyse the impact of leaf physiology on the diurnal, seasonal, and inter-annual fluctuations in gas exchange in a warm-temperate evergreen broad-leaved forest in Japan. The influences of physiological parameters at the single leaf scale on the canopy scale gas exchange were investigated, including normalised dark respiration rate, R nleaf25, normalised maximum carboxylation rate, V cmax25, and the stomatal coefficient, m, of an improved ball-type stomatal conductance model. Simulated sensible and latent heat fluxes and CO 2 flux at the canopy roughly reproduced the amplitude and diurnal and seasonal fluctuations in the observed fluxes, with the constant m and one set of reference V cmax and R nleaf with their temperature dependences. Overestimations of latent heat flux and thus underestimation of sensible heat flux with a constant m demonstrated that additional stomatal closure should be expected during a drought period. Overestimation of CO 2 flux during the leaf expansion period and the severe drought period with changing m values related to soil moisture conditions demonstrated that the decline in canopy scale CO 2 uptake during these periods was related to some physiological restraints, other than simple uniform stomatal closure, at the single leaf scale.

Variation in tree growth, mortality and recruitment among topographic positions in a warm temperate forest

Questions: Do the population dynamics of trees differ among topographic positions and, if so, how does topographic position affect the population dynamics of species that are distributed in a topography-specific manner? Which is the most important life stage in determining vegetation patterns? Location: Primary and secondary warm temperate evergreen broad-leaved forest (40 - 280 m a.s.l.) on the western part of Yakushima Island, Japan. Methods: Mortality, recruitment, DBH growth and distribution of stems (≥ 5 cm DBH) in a 2.62-ha plot were surveyed in 1992 and 2002 to determine the relationships between population parameters and (1) topography and (2) distribution patterns of 17 common tree species. Results: Common species (n = 17) were classified into three distribution pattern groups: group A, distributed mainly on convex slopes; group B, on concave slopes, and group C, not aggregated with respect to topographic position. Stem mortality, recruitment and DBH growth were greater in group A than in group B within each topographic class. The hierarchy of stem mortality among topographic classes for groups A and B was convex > planar > concave. Stem recruitment density was relatively high on the convex and concave slopes, respectively, for groups A and B. Conclusions: The topographical positions of adult trees were not always most suited for adult survival and growth. For group A, the distribution pattern of adults was determined in the juvenile stage, while this was not the case for group B. Studies of juvenile stages are important for understanding the demographic basis of vegetation distribution patterns.

Three years of carbon and energy fluxes from Japanese evergreen broad-leaved forest

Carbon dioxide and sensible and latent heat fluxes over a warm-temperate evergreen broad-leaved forest in central Japan observed for 3.5 years using the eddy covariance method were analysed with an extended big-leaf model. Net ecosystem production (NEP) was estimated after correcting for night-time efflux by using chamber observations of soil and leaf respiration and for day-time CO 2 flux by using the light–response curve. Peak CO 2 uptake occurred during early summer and autumn; a summer depression and winter uptake were also characteristic of this forest. The estimated NEP showed differences among the years, depending on drought and radiation conditions. The mid-day average of surface conductance was fluctuated between 5 and 10 mm s −1 during normal years and sometimes decreasing in dry summers. In the wet summer, it increased up to 20 mm s −1. During the severe and long-term drought, the surface conductance was clearly depressed, suggesting that the surface conductance was strongly influenced by drought. The canopy maximum carboxylation rate (big-leaf V CMAX) was derived from 30 min fluxes using the same inversion procedure as used in leaf-level analysis. V CMAX at the normal period was generally explained with one temperature-dependence curve ( V CMAX25: 58.4 μmol m −2 s −1, Δ H a: 32,200 J mol −1) at this warm-temperate evergreen broad-leaved forest. The decline of the normalised V CMAX ( V CMAX25) was detected during the severe drought and the expanding period. V CMAX25 did not recover after rain during winter of the year of the severe drought, which suggests that leaf function had suffered severe damage.

Effects of a Severe Typhoon on Forest Dynamics in a Warm-temperate Evergreen Broad-leaved Forest in Southwestern Japan

The effects of a typhoon on forest dynamics and the response of major tree species were studied in a warm-temperate evergreen broad-leaved forest in southwestern Japan. The strongest typhoon on record (T9313) passed through this region in 1993. Return periods of typhoons over 30 ms−1 in instantaneous wind velocity and T9313 were estimated to be 2.2 and 104.5 years, respectively. Approximately 10% of all stems suffered some damage from T9313 and annual stem mortality rose from 1.3 to 2.7%. The estimated period that the number of stems would fall below 10% of the initial was four years shorter with T9313-class typhoons than without them. Thus, the disturbance by T9313 was not catastrophic at the site although T9313 was an episodic typhoon. The short-term responses of major tree species to T9313 were classified into four types: 1) blunt-response type with little decrease and recruitment of stems in the DBH ≥ 5 cm class (Distylium racemosum), 2) retreat type with larger decrease than recruitment (e.g. Quercus acuta), 3) sharp-response type with a large decrease and much recruitment (e.g. Cinnamomum japonicum), and 4) advance type with less decrease than recruitment (Eurya japonica). Among the four regeneration types classified by previous studies (climax, light-demanding, subcanopy, and few-sapling), the climax and few-sapling types each showed a specific short-term response, the blunt-response and retreat types, respectively, that explains one aspect of the regeneration strategies of each type. On the other hand, the light-demanding or sub-canopy type showed multiple short-term responses, indicating that each regeneration type contains species with various regeneration strategies.

Patterning of Subtropical ⁄ Warm-temperate Evergreen Broad-leaved Forests in East Asian Mountains with Special Reference to Shoot Phenology

熱帯山地林の北限に相当する日本の常緑広葉樹林を構成する樹種は，大きく分けて林冠を構成する亜中形葉のブナ科·クスノキ科などの高木種群と下層を構成する小形葉のヤブコウジ科·ハイノキ科などの低木種群とから構成されている。前者は熱帯山地林のうち樹高の大きい下部山地林を構成する要素であり，後者は樹高の小さい上部山地林の要素である。熱帯山地で異なる垂直分布帯を構成するこれら2 群が北限の日本では同じ森林の階層をすみ分けるかたちで共存するという大変興味深い地理的パターンがみられる。日本に分布するこれら北限の常緑広葉樹はヒサカキ以外はいずれも一回だけ春に落葉(春季落葉)と出葉が同時に起こり，熱帯で普通にみられるような2-3 回の出葉を繰り返すものや，連続的に成長する種はない。季節変化がない熱帯から季節性が強い北限の温帯に向かつてシュートフェノロジーは単純化してしまう。さらに春のシュートの伸長成長を比較すると林冠木は急速で，短期間に終わるが，シュート長は長いのに対して，下層木はゆっくり，長期間成長し，シュート長は短いという違いが見られた。このようなフェノロジーの特性と対応して芽の構造が明らかに異なり，林冠木は鱗片が10-20枚も重なった構造をもつのに対して，下層木の芽鱗は外側が一番大きく， 1-2 枚の鱗片しか見えない。このような特徴的な2群の林冠·下層種群は系統的にも特定の分類群の組み合わせからなり種数のレベルでは高緯度に向かつて貧化していくが，リーフサイズスペクトルでみると常緑広葉樹林の北限まで同じセットが維持され，基本構造は変わらないことがわかる。

Modeling the relationship between the asymmetry in crown display and local environment

The asymmetry in crown display was modeled with respect to neighbors and microtopography. The direction and magnitude of the asymmetry were expressed by the ‘crown-vector’, the horizontal two-dimensional vector that joins the stem base position of a focal tree with the centroid of its projected crown area. In the model, the crown-vector of a focal tree was a function of the position and size of its neighbors and the direction and inclination of the slope on which it occurred. Using the model, the effect of repelling behavior of crowns on the spatial pattern of crowns was quantified; spatial patterns of crowns were more regular than those of stem bases. The effects of parameters in the model on the spatial pattern of population were also quantified. The model was applied to the data derived from two study plots: one in cool temperate deciduous broad-leaved forest in northern Japan and the other in warm temperate evergreen broad-leaved forest in central Japan. The least-squares fit of the model accounted for 56% and 73% of the total variance in crown-vector for the two study plots, respectively.