Beech Forest In Japan Research Articles

Responses of a bird community to sporadic outbreaks of woody herbivorous insects in a temperate beech forest in Japan

Sporadic large outbreaks of herbivorous insects alter forest ecosystems via a top-down effect, and a high frequency of outbreaks led to the death of the trees on which the insects fed. The top-down effect of predators, such as other insects and birds, often regulates the outbreaks. Predator insects exert effective top-down control on outbreaks of herbivorous insects, but the effect of bird predation varies because birds have a broader diet range and higher mobility than insects. It was hypothesized that when large insect outbreaks occur during the breeding season of birds, most bird species would not respond owing to a fixed home range during this season and would, therefore, not exert top-down effects. To test this hypothesis, the relationship between bird and beech sawfly abundance was investigated for over nine years in the Tanzawa Mountains of central Japan, where temperate beech forests and large sporadic outbreaks of woody herbivorous insects occur. In this study, 28 649 female beech sawfly adults were captured, and 2515 individuals were identified from 50 bird species. The abundance of most bird species foraging on beech sawfly larvae, except Sitta europaea, did not increase proportionally with the number of beech sawfly adults. Many bird species did not respond to the unpredictable and temporary abundance of food resources in a way that would enhance their density, supporting the hypothesis. These results can be explained by examining the nesting and foraging guilds of the birds. S. europaea is less restricted in nesting sites and nests earlier in the season than other species; therefore, they could select nests in areas where beech sawfly larvae were abundant. Regarding foraging, S. europaea has a unique foot shape that allows it to move down the tree trunk freely and respond rapidly to fluctuations in beech sawfly abundance. Bird species that exert top-down effects on insects show promise for use in an integrated pest management approach to manage sporadic outbreaks of herbivorous insects in forest ecosystems.

Relationship between Canopy Structure and Community Structure of the Understory Trees in a Beech Forest in Japan

Understory trees occupy a spatially heterogeneous light environment owing to light interception by patchily distributed canopy leaves. We examined the spatial distribution of canopy leaves and the spatial structure of the understory tree community (height < 5 m) and their relationships in a beech forest in Nagano, Japan. We measured the canopy leaf area index (LAI) at 10 m intervals (n = 81) in a permanent research plot (1 ha). We established a circular subplot centered on each LAI measurement point, and determined the species composition and the aboveground net primary production of wood (ANPPW) of the understory tree community by using tree size data from an open database in the Monitoring Sites 1000 project. There was a significant negative correlation between canopy LAI and the ANPPW of understory trees and a significant positive correlation between the ANPPW of understory and understory tree density. The dominant species of understory trees differed between subplots with high and low LAI values. Our results suggest that niche differentiation allows trees in the understory community to make use of various light conditions, thereby enhancing the primary productivity of the entire community.

Dynamics of dwarf bamboo populations and tree regeneration over 40 years in a clear-cut beech forest: effects of advance weeding and herbicide application

ABSTRACT We explored the dynamics of dwarf bamboo populations in a beech forest 11 years before and 30 years after clear-cutting. Repeated weeding or herbicide application (sodium chlorate) was used experimentally to reduce or eliminate dwarf bamboo prior to clear-cutting. At the beginning of the study, the understory comprised dense populations of two Sasa species, the dominant S. palmata and the less common S. kurilensis. Both weeding and herbicide application rapidly reduced the cover of S. palmata, but it began to recover prior to clear-cutting and soon exceeded initial cover values. Both weeding and herbicide application reduced the cover of S. kurilensis to near-negligible levels; the cover increased slowly after clear-cutting but remained below initial levels. Weeding or herbicide application resulted in different patterns with respect to height; height decreased rapidly in response to weeding, whereas herbicide application had more gradual effects. Height began to increase after clear-cutting, and S. palmata exceeded its initial height, reaching 1.5–2.0 m in the 10–15 years following clear-cutting. No tree recruits were found in sites where dwarf bamboo was left unmanaged. Weeding and herbicide application facilitated recruitment of Betula ermanii after clear-cutting, but recruits of Fagus crenata, which originally dominated the forest canopy, remained scarce or non-existent at 30 years after clear-cutting. We postulate that natural regeneration of Fagus is nearly impossible following clear-cutting in temperate beech forests in Japan with dense undergrowth of Sasa, even with advance measures to reduce or eliminate Sasa.

Survival and recruitment of Sasa kurilensis culms in response to local light conditions in a cool temperate forest

ABSTRACT Dwarf bamboos (Sasa spp.) are clonal plants and are known to inhibit tree regeneration. In natural conditions, however, culm dynamics in response to local light conditions is not fully understood. In this study, we examined the relationship between local light conditions and culm survival or recruitment of Sasa kurilensis in an old-growth beech forest in Japan. We identified 1466 S. kurilensis culms with lengths ≧0.5 m in forty 2 × 2 m quadrats in 2014 and recorded their survival rate and the number of newly recruited culms in 2015. From 2014 to 2015, the number of dead and recruited culms in 160 m2 area were 179 and 118, respectively. Our model indicated that the recruitment density was not influenced by the horizontal light intensity, and it increased as the number of pre-existing culms increased. In contrast, culm survival rate increased with an increase in the horizontal light intensity just above the Sasa layer and with a decrease in the degree of shading by the conspecific leaves. This finding suggests that the life span of S. kurilensis culms both horizontally and vertically varies in response to local light variations in the old-growth beech forest.

New phytosociological classification of beech forests in Japan

New phytosociological classification of beech forests in Japan

The epiphytic communities of beech forest in Japan

The epiphytic communities of beech forest in Japan

Can we estimate forest gross primary production from leaf lifespan? A test in a young Fagus crenata forest

It has been well established that leaf longevity is linked to the carbon economy of plants. We used this relationship to predict leaf lifetime carbon gains from leaf lifespan, and estimated the gross primary production (GPP) of a young deciduous forest of Japanese beech (Fagus crenata) located in central Japan. The light-saturated photosynthetic rates of the leaves were measured repeatedly during the growing season. We used the leaf lifespan to calculate the conversion coefficient from the light-saturated photosynthetic rate into the realized leaf lifetime carbon gain under field conditions. The leaf turnover rate was estimated using litter traps. GPP was estimated as the product of lifetime carbon gain per unit of leaf mass, and the annual leaf turnover rate. The GPP of the forest in 2007 was estimated to be <TEX>$1.2{\times}10^3gCm^{-2}y^{-1}$</TEX>, which was within the range of previously reported GPP values of beech forests in Japan, and was close to the GPP of a European beech forest, as estimated by eddy flux measurements.

Decomposition of Japanese beech wood by diverse fungi isolated from a cool temperate deciduous forest

We assessed 62 fungal strains in 31 species of wood decay fungi in the ability to decompose wood blocks of Japanese beech (Fagus crenata) under a pure culture condition. Fungi were collected in a cool temperate beech forest in Japan and isolated from the inside of beech logs and from sporocarps fruiting on logs and snags of beech that were different in diameter and decay class. Fungi in Holobasidiomycetidae showed marked decomposition of lignin and carbohydrate. These fungi were divided into three groups according to the pattern of lignin and carbohydrate utilization. Phanerochaete filamentosa decomposed lignin selectively. Lampteromyces japonicus, Steccherinum rhois, Trichaptum biforme, Stereum ostrea, Mycena haematopoda, Antrodiella albocinnamomea, Daedalea dickinsii, Daedaleopsis tricolor, Ganoderma tsunodae, and Trametes versicolor decomposed lignin and carbohydrates simultaneously. Psathyrella candolleana, Lenzites betulinus, and Trametes hirsuta decomposed carbohydrates selectively. Species in the Phragmobasidiomycetidae and in the Ascomycota caused low mass loss of wood.

Population dynamics of the beech caterpillar, Syntypistis punctatella, and biotic and abiotic factors

AbstractThe beech caterpillar, Syntypistis punctatella (Motschulsky) (Lepidoptera: Notodontidae), often causes extensive defoliation of beech forests in Japan. Outbreaks have often occurred synchronously among different areas at intervals of 8–11 years. Synchrony of outbreaks was considered to be caused by synchrony of weather. Populations of this insect exhibit periodical dynamics in both outbreak and nonoutbreak areas. Factors that might influence the population dynamics of the beech caterpillar were classified from the point of view of the natural bioregulation com‐plex, which includes a coleopteran predator, Calosoma maximowiczi, avian predators, parasitoids, entomopathogenic fungi, and delayed induced defensive response (DIR) of beech trees. Because such periodic population dynamics are believed to be caused by one or more delayed density‐dependent factors, delayed density‐dependent mortality has been identified as a likely source of population cycles. The DIR and pathogenic diseases showed a high order of density dependence. An infectious pathogen, Cordyceps militaris, was considered to be the most plausible agent responsible for periodic dynamics of the beech caterpillar population because insect diseases were effective in cases in which the S. punctatella population started to decrease without reaching outbreak densities, but DIR was not. Conspicuous defoliation caused by this insect tends to occur at certain elevations, where forests are composed of pure stands of beech trees. I propose three different hypotheses to explain this phenomenon: the diversity–stability hypothesis, the resource concentration hypothesis, and the altitudinal soil nutrient hypothesis.

Suppression and release during canopy recruitment in Fagus crenata and Acer mono in two old-growth beech forests in Japan

Beech forests occur widely in the mountains on the main island of Japan. Wind storm is the major regime that causes canopy disturbances in these forests. Fagus crenata Blume is a dominant, and Acer mono Maxim., also a canopy species, co-occurs in these forests. It has been suggested that A. mono is less shade-tolerant than F. crenata. Using dendrochronological data, this study describes suppression and release histories during canopy recruitment for these two species in two old-growth beech forests (at Takahara and Kaname) and provides support for the shade tolerance suggestion given above. In addition, disturbance histories over the past 130 or 160 yr in the two forests have been reconstructed. At Takahara, the forest experienced more frequent wind storms, was about 10–15 m shorter and less dense than that at Kaname. Kaname is in a heavy snow region. On average, F. crenata experienced 1.4 and 2.5 definable episodes of suppression during canopy recruitment at Takahara and Kaname, respectively. At Kaname, the average length of total suppression was 66 yr, and 34 yr at Takahara. On average, at final release, the beech trees had a diameter of 25 cm and an age of about 125 yr old, which were twice as large and twice as old as those at Takahara. In contrast, at the two sites, A. mono experienced similar average numbers of episodes (1.6 episodes at Takahara and 1.8 episodes at Kaname) and similar average length of total suppression (37 yr at Takahara and 30 yr at Kaname) during canopy recruitment. At both sites, at final release, the maple had an average diameter of about 18 cm and an average age of some 70 yr. Our results have revealed that F. crenata is able to be tolerant of a longer shade suppression than A. mono. At Kaname, the canopy disturbances deduced from tree-ring data were more intense or frequent than those at Takahara, This contrasted with occurrences of wind storms at the two sites.

Geographic variation and maintainance of species diversity of beech forests in Japan

Geographic variation and maintainance of species diversity of beech forests in Japan

Regeneration of beech (Fagus crenata) after the simultaneous death of undergrowing dwarf bamboo (Sasa kurilensis)

AbstractSeedling recruitment and survivorship of beech (Fagus crenata) were studied with special reference to the simultaneous death of undergrowing bamboo (Sasa kurilensis). The survival rate of beech seedlings on the floor where Sasa had withered was much higher than that on the floor where Sasa survived. Damping off caused the largest mortality among beech seedlings. However, the allocation pattern of matter to different parts of the seedlings indicated that their survival was greatly affected by production economy. The dense cover of dwarf bamboo prevented the establishment of beech seedling banks on the forest floor. The interval between the times when simultaneous death of Sasa occur and the length of its recovery period are thus important factors controlling the dynamics of beech forests in Japan.

Regeneration dynamics of beech forests in Japan

Regeneration dynamics of beech forests in Japan

Diffused light conditions in canopy gaps in a beech (Fagus crenata Blume) forest.

A simple model for diffused light conditions in canopy gaps is presented. The vertical changes of illuminance in gaps calculated from the model agreed with the changes observed in a beech forest in Japan. The illuminance in a given sized gap in the forest could be estimated from the model. Size distribution of gaps in the forest suggested that most gaps were too small for the frequent occurrence of pioneer tree species.