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Long‐term record of leaf phenology of woody plants that have high longevity and that have been growing on the same site for a longer time could be one of the good indicators for assessing the effects of climate change on forest ecosystem functioning. Since climatic conditions could be different among locations, we need to record the phenology of forest plants growing under various climate types. Here, we report seasonal changes in leaf abundance of deciduous trees during a 13‐year period in the Sambe Forest of Shimane University located in northern Chugoku mountain range, western Japan (35°9′N, 132°37′–40′E, 300–628 m above sea level [asl]). Northern Chugoku mountain range is situated in the west end of Japan Sea side climate. Our study would provide the first record of tree phenology in this region. We examined eight species belonging to eight genera common in a secondary deciduous broad‐leaved forest in western Japan. Habitats of native trees ranged from canopy to understory in the forest and pioneers in an open site. Some of trees were exceptionally planted in an arboretum in the Sambe Forest. Leaf types included single leaf (i.e., Carpinus tschonoskii, Swida macrophylla, etc.) and pinnate leaves (i.e., Aesculus turbinata and Phellodendron amurense). We observed changes in the relative leaf abundance caused by budburst, leaf expansion and leaf shedding of the fixed shoots of targeted trees during 3‐day to 3‐week intervals from March to December each year from 2004 to 2016. Over the 13‐year period, we used a digital camera to take photographs of the shoots that were processed to estimate the leaf abundance. Our data was obtained from common tree species that have a wide habitat range and are distributed nationwide. Therefore, comparison of our data with those data in other climate types may significantly contribute to understand the effect of climate change across Japan on forest plants. The complete data set for this abstract published in the Data Paper section of the journal is available in electronic format in MetaCat in JaLTER at http://db.cger.nies.go.jp/JaLTER/metacat/metacat/ERDP-2020-20.1/jalter-en. [ABSTRACT FROM AUTHOR]

Swidden agriculture, commercial logging and plantation development have been considered to be the primary common causes of degradation and loss of tropical rain forests in Southeast Asia. In this paper, I chose a part of northeastern Sarawak, East Malaysia as my case study area to analyze the changes in its land-use characteristics. In the study area, as well as primeval forests, we see that land use began about 100 years ago by a native group called the Iban; commercial logging began in the 1960s, and the development of oil palm plantations began recently. I describe the changes in land use as well as their social and economic causes by referring to aerial photographs, literature surveys, interviews with government officers and the Iban, and observation of land use. My analysis of land use demonstrates that on “state land”, where commercial logging and oil palm plantation development are occurring, large areas of forest have been disturbed in a short period of time. The objective is to benefit economically in response to the social and economic conditions surrounding the study area. On the other hand, in the “Iban territory,” where the Iban practice their land use, land conversion has not occurred on a large scale and in a short period of time, even though the forest has been cut and agricultural fields have been created in response to social and economic conditions as well. They disperse small agricultural fields throughout their forest land. Therefore, the landscape of the “Iban territory” is based on secondary forest, composed of patches of forest in various stages and with several types of agricultural land. Today in Sarawak, monocrop plantations are rapidly expanding and little primeval forest remains. Given these conditions, the land-use practices of natives such as the Iban will be evaluated from the viewpoint of ecosystem and biodiversity conservation. It could play an important role in providing habitats for natural wildlife. [ABSTRACT FROM AUTHOR]

This data paper reports tree census data collected in a network of 34 forest sites in Japan. This is the largest forest data set freely available in Japan to date. The network is a part of the Monitoring Sites 1000 Project launched by the Ministry of the Environment, Japan. It covers subarctic to subtropical climate zones and the four major forest types in Japan. Forty-two permanent plots, usually 1 ha in size, were established in old-growth or secondary natural forests. Censuses of woody species ≥15 cm girth at breast height were conducted every year or once during 2004 to 2009. The data provide species abundance, survivorship and stem girth growth of 52,534 individuals of 334 tree and liana species. The censuses adopted common census protocol, which provide good opportunities for meta-analyses and comparative studies among forests. The data have been used for ecological studies as well as for the biodiversity reports published by the Ministry of the Environment. [ABSTRACT FROM AUTHOR]

The evergreen oak Quercus glauca often dominates secondary broadleaved forests in Western Japan. It is regarded as a mid-successional species, whose diameter and height growth fall between those of early- and late-successional species. Despite the ecological importance of this evergreen oak in the secondary succession of the evergreen broadleaved forest zone in Japan, tree-felling data that allow estimations of tree mass and leaf area from non-destructive measurements are lacking. This paper provides stem growth data, read from tree rings on disks sampled from 13 Q. glauca stems, and their allometric data. The samples were collected in 1994 from the Ginkakuji-san National Forest, Kyoto City, Japan. Allometric data comprised data on stem age, diameter at breast height, diameter at 10% height, tree height, height of the lowest living branch, height of the lowest living leaf in the crown, volume of the main stem, squared stem diameter just below the lowest living branch, total leaf area of the stem, dry weight of the total leaves, dry weight of all branches, dry weight of the main stem, total aboveground dry weight, mean relative photosynthetic photon flux density (PPFD) above the crown, mean relative PPFD below the crown, crown projection area, and specific leaf area. These data can be helpful for estimating the biomass and leaf area index of a Q. glauca stand by enabling the derivation of allometric relationships between non-destructive measurements (such as stem diameter at breast height, and tree height) and tree mass or leaf area. Diameters (including bark thickness) at ground height and above (at 0.5- or 1-m intervals) for each stem are also provided. Stem growth data were based on tree-ring reads from disks taken from heights of 0.0 and 0.3 m, and at 0.5-m (stem height <7 m) or 1.0-m (stem height ≥7 m) intervals above that. Stem volume growth derived from these tree-ring data can be converted into stem mass growth if combined with an analysis of the allometric data, which may serve as a useful resource for the estimation of carbon fixation by evergreen oaks in relation to global climate change. [ABSTRACT FROM AUTHOR]

Understanding the relationship between functional and species diversity as well as their association with habitat heterogeneity can help reveal the mechanisms of species coexistence in ecological communities. However, these interactions have been poorly studied in subtropical forests. In this paper, we evaluated functional diversity (as measured by Rao's Q) and traditional species diversity (based on Simpson's index) in a 24 ha forest plot in a subtropical evergreen broad-leaved forest (EBLF) in China. We compared the sensitivities of functional and species diversity to topographic variables (elevation, convexity, slope and aspect) at multiple spatial scales based on 10 × 10, 20 × 20, 40 × 40 and 50 × 50 m quadrats. Functional and species diversity were found to have different distribution patterns along a topographical gradient, with functional diversity better explained by topography than was species diversity using a spatial autocorrelation regression error model. Furthermore, functional diversity had a significantly greater association with topographic variables than species diversity in both adult and young trees; in both cases, the strength of the diversity-habitat association increased with quadrat size. We conclude that functional diversity reflects a greater diversity-habitat association in EBLF than does species diversity, and that the association depends on the spatial scale and life stages of the woody plants under evaluation. [ABSTRACT FROM AUTHOR]

Fruit-frugivore interactions have received great attention from evolutionary, ecological and applied perspectives. However, despite the fact that large-scale approaches may offer new insights on fruit-frugivore interactions, little work has been devoted to exploring the factors shaping large-scale variation of seed dispersal. This paper studies the spatial variation in seeds regurgitated within pellets by wintering thrushes (genus Turdus) in a set of 26 Spanish juniper ( Juniperus thurifera) woodlands scattered along a latitudinal gradient during two winters of contrasting cone and bird abundance. It explicitly explores whether pellet rain variation among woodlands was related to changes in vegetation cover, temperature, day length duration and bird abundance. Top regression models in the Akaike information criterion framework explained 34 % and 70 % of variance in pellet numbers in low and high crop and bird abundance years, respectively. In both winters, the spatial variation in pellets correlated to thrush abundance and day length duration. Pellet abundance linked to cone distribution only in the year of high crop, in which many migratory, extra-Iberian thrushes arrived to exploit the resource. Strong dependence of seed dispersion on large-scale features affecting bird numbers (e.g. the arrival of extra-Iberian migratory birds) and feeding behaviour (e.g. latitudinal variation in day length duration) suggests a primary role for variables acting at large scale on this mutualistic interaction. [ABSTRACT FROM AUTHOR]

Competition for seed dispersers is supposedly a selective force that drives the evolution of plant reproductive traits. In the understory of tropical forests, such competition should be especially severe among bird-dispersed plant species because (i) the production of copious fruit crops is limited by low light availability; (ii) there usually is a high density of fleshy fruited plants, and (iii) understory frugivorous birds are not abundant. In this paper, we took advantage of a high-density population of Geonoma pauciflora, a bird-dispersed palm species growing in the understory of the Brazilian Atlantic forest, to investigate the influence of plant traits and its immediate neighborhood on fruit removal. Intrinsic (crop and fruit sizes) and extrinsic traits (related to light availability) affected the fruit removal of G. pauciflora. Crop size had a greater influence than fruit size on the absolute number of fruits removed, whereas none of the investigated traits influenced decisively fruit removal efficiency (i.e., the proportion of an individual’s crop removed). The influence of light availability was mostly indirect, through its positive influence on fruit production. A significant positive spatial autocorrelation in removal efficiency occurred among neighboring plants within a 7-m radius, which is indicative of facilitation among neighboring individuals. The consequence of such positive spatial autocorrelation in removal efficiency for clonal plants such as G. pauciflora is that by attracting a frugivore a given ramet may promote the removal of fruits of other ramets, thus enhancing the reproductive output of the genet as a whole. [ABSTRACT FROM AUTHOR]

Nutrient resorption from senescing leaves is a key nutrient conservation strategy in many ecosystems. In evergreen broad-leaved forests, nutrient resorption occurs with concomitant defoliation almost year-round. However, it is unclear whether nutrient resorption efficiency (NuRE) varies in different defoliation seasons for evergreen broad-leaved trees and how it may relate to soil nutrient availability. Castanopsis eyrei is a dominant tree species in evergreen broad-leaved forests in southern China, with distinct bimodal patterns of defoliation in spring and autumn. We investigated seasonal variation of the resorption efficiency of nitrogen (N) and phosphorus (P) of C. eyrei leaf and its relationship with soil mineral N by measuring the concentrations in leaf, leaf litter, and soil for two consecutive years. We hypothesized that leaf NuRE should be higher in seasons with low soil nutrient availability. We found that on average, soil mineral N content was 38.5 % lower during the autumn defoliation peak than in spring, and N and P concentrations in leaf litter at the spring defoliation peak were 10.0 and 26.7 % higher than at the autumn peak. Nitrogen NuRE at the autumnal defoliation peak was 5.1 % higher than that at the spring peak (49.3 vs 44.2 %), and the phosphorus NuRE in autumn was 6.8 % higher than that in spring (77.6 vs 69.8 %). Our findings suggest an inverse relationship between soil nutrient availability and NuRE and that the dynamics in NuRE should be incorporated into modeling of biogeochemical cycling in evergreen forest ecosystems with a bimodal defoliation pattern. [ABSTRACT FROM AUTHOR]

Tropical deforestation is well known to have serious negative consequences for biodiversity, terrestrial carbon sinks and the balance of atmospheric greenhouse gases. By contrast, selective logging of tropical forests is often regarded as having a lesser impact on the ecosystem particularly in long terms, even though there have been few critical evaluations of the practice, particularly in Africa. We compared field data from 511 plots in the tropical forest of Sierra Leone, Ghana, Cameroon and Gabon. These plots were subject to different forest management practices: no recent logging (primary forests), selective logging (up to 30 years old) and re-grown secondary forests post clear-cutting (at least 20 years ago). Our findings suggest that the vertical structure and plant richness of the selectively logged and secondary forests change in different amplitude from those of primary forests, but stem density and the prevalence of vine and weed species differ greatly. We show that the effects of selective logging are greater than those expected simply from the removal of commercial species, and can persist for decades. Selective logging, unless it is practiced at very low harvest intensities, can significantly reduce the biomass of a tropical forest for many decades, seriously diminishing aboveground carbon storage capacity, and create opportunities for weeds and vines to spread and slow down the ecological succession. [ABSTRACT FROM AUTHOR]

Bio-indicators are often proposed to set conservation priorities in forest habitat owing to the difficulties of determining forest intrinsic ecological value. Here, we tested the efficacy of a number of potential bird indicator groups in monitoring beech Fagus sylvatica forest status by analyzing their associations with the spatial and structural variables of forest vegetation that indicate key ecological patterns and processes. The density of cavity nesting birds, indicating the presence of limited forest resources (resource-limited indicators), was influenced by tree species diversity, vertical species mingling and diameter, parameters reflecting maturity, gap-dynamic processes, as well as resource and shelter availability. Heterogeneity in shrub species composition, another parameter depending on forest dynamics, was positively associated with the occurrence of Capercaillie, a 'flagship' species for forest conservation. The presence of woodpeckers, a 'keystone' group that provides shelter and foraging substrate to other organisms, was positively affected by the basal area of standing dead trees that is indirectly associated with natural nutrient availability. These findings suggest that single indicators fail to provide a complete assessment of forest status, and their use in monitoring or managing forest ecosystem need to be contextualized to specific ecological patterns. The combined use of several indicators, representing various taxa, functions and life histories, appears to be preferable, and is logistically feasible if these can be surveyed together. Several indicators would likely display a wider range of sensitivities to the modification of natural processes and permit more comprehensive tracking of forest dynamics than single flagship, keystone or resource-limited indicators. [ABSTRACT FROM AUTHOR]

Industrial timber plantations severely impact biodiversity in Southeast Asia. Forest fragments survive within plantations, but their conservation value in highly deforested landscapes in Southeast Asia is poorly understood. In this study, we compared bird assemblages in acacia plantations and fragmented forests in South Sumatra to evaluate each habitat's potential conservation value. To clarify the impact of habitat change, we also analyzed the response of feeding guild composition. Five habitat types were studied: large logged forest (LLF), burnt logged forest (BLF), remnant logged forest (RLF), 4-year-old acacia plantation (AP4), and 1-year-old acacia plantation (AP1). Estimated species richness (Chao 2) was highest in LLF then AP4 and BLF, while AP1 and RLF had lower estimated species richness. Community composition was roughly divided into two groups by non-metric multidimensional scaling ordination: acacia plantation and logged forest. Sallying substrate-gleaning insectivores, such as drongos, broadbills, and some flycatchers, were restricted to LLF, whereas acacia plantation hosted many terrestrial frugivores, such as doves. Although fragmented forests in our study site lacked several common tropical forest species, these fragments provide an important habitat for some sallying and terrestrial insectivores. A network of small riparian remnant forests could be a complementary habitat for some species, while the conservation value of burnt forest might be low. In conclusion, the highly fragmented forests in plantations are suboptimal habitats for birds but are still very important, because large primary forest blocks have been nearly lost in the surrounding landscape. [ABSTRACT FROM AUTHOR]

Landform has long been considered one of the primary controls on forest community structure; however, it is still unclear how the strength of such species-topography couplings varies in response to recurring disturbance events. We evaluated this question in the context of repeated prescribed fire applied to a forest landscape in eastern Kentucky, USA. The landscape encompassed different areas of varying treatment frequencies: no fire, less frequent fires (two times, 6-year interval), and frequent fires (four times, 1 or 2-year interval) over 8 years. For each of 32 plots (10 m × 40 m), species-landform data were collected seven times between 2002 and 2010. Results of canonical correspondence analysis showed generally decreasing importance of terrain attributes to the overall tree species composition, during and after the period of fire disturbance. Before fire, species composition showed high fractal dimensions and low Moran's I, implying that the complex terrain of the area provided local, site-specific topographic controls on community structure. As fire was repeatedly applied, fractal dimensions decreased and Moran's I increased, indicating that plots possessed increasingly similar vegetation characteristics regardless of site-specific terrain conditions; that is, local topography no longer acted as the primary driver of species composition because such a short-range spatial control became overwhelmed by a longer-range variation dictated by fire. Following a period of fire disturbance, forest modelers are recommended to avoid species distribution modeling heavily based on topographic parameters and to explicitly take into account potentially increasing spatial autocorrelation in species composition. [ABSTRACT FROM AUTHOR]

We investigated how environmental variables explain patterns of tree regeneration in high altitude sub-tropical Quercus-dominated forests by: (1) determining whether the seedling and sapling communities show non-random spatial patterns of floristic composition; (2) identifying which environmental variables explain the observed patterns of floristic composition; (3) examining if similarity in floristic composition is related to similarity in environmental variables. We used data gathered in permanent plots established across 10 km in high altitude sub-tropical Quercus-dominated forests. Our analyses consisted of unconstrained ordination analyses (Non-metric Multidimensional Scaling) to characterize the spatial patterns of floristic composition; constrained ordination analyses (Canonical correspondence analysis) to assess the contribution of environmental variables in explaining patterns of floristic composition and, the simple and partial Mantel test to correlate the floristic composition similarity to environmental similarity. Our results provided evidence of non-random spatial patterns of floristic distribution due to structured environmental filters such as canopy-related variables, litter, grazing and aspect. Floristic compositional similarity did not depend on geographical distance between sites or on differences in their environment; therefore a number of plots were similar in floristic composition, in both seedlings and saplings, but have no environmental similarity. [ABSTRACT FROM AUTHOR]

This study aimed to reveal the soil seed accumulation processes for endozoochorous plants in the heavy-snowfall forests of Japan, where seed dispersal agents are few when compared to tropical forests. We assessed (1) primary seed dispersal by Japanese macaques ( Macaca fuscata) by identifying dispersed seeds found in their feces, and (2) secondary seed dispersal by dung beetles by using beads (as seeds mimics) of different sizes, to quantify the frequency of seed burial and burial depths. We studied this diplochorous system in different forest types (undisturbed beech forest, conifer plantation, and secondary beech-oak forest) and during the spring and summer seasons. The key findings were as follows: (1) macaques dispersed the seeds of 11 and 14 plant species during spring and summer, respectively; (2) seeds dispersed by macaques in the spring were smaller and twice as abundant than those dispersed in the summer; (3) although no differences were observed in the amount of beads buried by beetles between seasons, all bead sizes tended to be buried in deeper soil layers in the spring than in the summer; and (4) the seed supply to the soil in undisturbed beech forest and conifer plantation was greater than the one in secondary beech-oak forest. Similar to what has been observed in tropical forests, seeds defecated by frugivorous mammals can be successfully incorporated into the underground soil seed bank through a diplochorous macaque-beetle system in temperate forests of deep snow regions. [ABSTRACT FROM AUTHOR]

Sarcoptic mange caused by Sarcoptes scabiei, is a highly contagious worldwide mite infection responsible for epizootic skin disease in populations of wild and domestic mammals. It causes skin disorders that may lead to severe generalized skin disease (mange). We investigated the spread and dynamics of sarcoptic mange in one of the best preserved carnivore communities in the Białowieża Primeval Forest over the last 20 years. Sarcoptic mange was found in 6 of 10 investigated species. The highest percentage of infected individuals was recorded in red foxes (19 %), European badgers (9 %), grey wolves (7 %), raccoon dogs (6 %), and stone martens (5 %). Other species were not infected (least weasel, American mink, European polecat, pine marten) or infected sporadically (Eurasian lynx--1 case). Rate of infection was correlated with the sum of ecological and behavioral features, which may increase the spread of infection. Outbreaks of sarcoptic mange occurred simultaneously in several species of carnivores, which indicates the occurrence of between species transmission. We found that the source of investigated individuals (trapped, culled and found dead) may influence the results of the analysis. Our study shows that in carnivore communities such as in Białowieża Forest, numerous species may serve as a reservoir of the pathogen and favor its persistence in the environment. This study indicates that sociality and use of den sites are important factors affecting sarcoptic mange spread and prevalence in wild populations of carnivores. [ABSTRACT FROM AUTHOR]

Tree survival is a critical driver of stand dynamics, influencing forest structure and composition. Many local-scale drivers (tree size, abiotic and biotic factors) have been proposed as being important in explaining patterns of tree survival, but their contributions are still unknown. We examined the relative importance of these local drivers on tree survival using generalized linear mixed models in an old-growth sub-tropical forest in south China at three levels (community, guild, and species). Among the variables tested, tree size was typically the most important driver of tree survival, followed by abiotic and then biotic variables. Tree size has a strongly positive effect on tree survival for small trees (10-30 cm dbh) and shade-tolerant tree species. Of the abiotic factors tested, elevation tended to be more important in affecting tree survival than other topographic variables. Abiotic factors generally influenced survival of species with relatively high abundances, for individuals in smaller size classes and for mid-tolerant species. Among biotic factors, we found that the mortality of tree species was not driven by density- and frequency-dependent effects in this sub-tropical forest, as indicated by the results of both total basal area of neighbors and the proportion of conspecific neighbors in our study. We conclude that the relative importance of variables driving patterns of tree survival varied greatly among tree size classes, species guilds, shade tolerance, density, and abundance classes in this sub-tropical forest. These results also provide critical information for future studies of forest dynamics and offer insight into forest management in this region. [ABSTRACT FROM AUTHOR]

Because of their overwhelming size over other organisms, trees define the structural and energetic properties of forest ecosystems. From grasslands to forests, leaf area index, which determines the amount of light energy intercepted for photosynthesis, increases with increasing canopy height across the various terrestrial ecosystems of the world. In vertically well-developed forests, niche differentiation along the vertical gradient of light availability may promote species coexistence. In addition, spatial and temporal differentiation of photosynthetic traits among the coexisting tree species (functional diversity) may promote complementary use of light energy, resulting in higher biomass and productivity in multi-species forests. Trees have evolved retaining high phenotypic plasticity because the spatial/temporal distribution of resources in forest ecosystems is highly heterogeneous and trees modify their own environment as they increase nearly 1,000 times in size through ontogeny. High phenotypic plasticity may enable coexistence of tree species through divergence in resource-rich environments, as well as through convergence in resource-limited environments. We propose that the breadth of individual-level phenotypic plasticity, expressed at the metamer level (leaves and shoots), is an important factor that promotes species coexistence and resource-use complementarity in forest ecosystems. A cross-biome comparison of the link between plasticity of photosynthesis-related traits and stand productivity will provide a functional explanation for the relationship between species assemblages and productivity of forest ecosystems. [ABSTRACT FROM AUTHOR]

The responses of aboveground parts of the forest to changes in environmental factors and stand age is well studied, but the same is not true for the belowground parts of the forest. Two plantation black locust ( Robinia pseudoacacia L.) forest sites were taken in the Loess Plateau of China, one in the drier, infertile, more sandy area of the middle Loess Plateau, and another in the wetter, fertile, more clay-filled area of the southern Loess Plateau. At each site, both a younger (8-year-old) plantation stand and an older (30-year-old) plantation stand were included to study the effects of soil physicochemical properties and stand age on the fine root (<2 mm) biomass and vertical distribution of black locust forests. Root samples were taken with soil cores to a depth of 100 cm. The fine root biomass decreased from the middle site to the southern site for both stand ages, as expected, and the decrease could be due to a higher fine root N concentration associated with a higher fine root turnover rate at the southern site. There was a similar rooting pattern, though not deeper, in the drier, sandy site as predicted based on soil water infiltration and evaporation demands. The different effects of stand characters (e.g., tree density, tree height) on the fine root distribution as compared with the environmental properties may contribute partly to the similar pattern found in the two sites. The fine root biomass increased with stand age in both sites. In contrast to the evident difference in fine root biomass, there was no clear trend in the fine root vertical distribution pattern with stand age. Our results indicate that fine roots are likely to respond to changes in soil physicochemical properties and stand age by changing fine root biomass rather than by varying rooting pattern. [ABSTRACT FROM AUTHOR]

Defining and quantifying biomass-density relationships in dense plant stands has been a long-standing issue in both theoretical and empirical studies. Most existing/traditional studies focus on whole plant individuals, without considering different plant components (e.g., stem, branch and leaf). However, the analysis of biomass-density relationships for different plant parts is linked to those for whole plants, and thus important for understanding plant strategies for utilizing resources and community dynamics. In our study, we investigated standing stem ( M), branch ( M) and leaf ( M) biomass-density relationships, across a range of forest communities in China. The results showed that there was no constant predicted value (e.g., −1/2 or −1/3 for M; −1/2, −1/3 or 0 for M and M) that can describe all the relationships, and that the scaling exponents for stem, branch and leaf biomass varied across different forest types. In particular, standing leaf biomass (leaf biomass per unit area) was not constant in these forest communities. Furthermore, stem biomass-density lines were steeper than corresponding branch and leaf lines across most of these forest communities. [ABSTRACT FROM AUTHOR]

Digestive plasticity, which refers to changes in digestive features due to changes in both internal and external environmental conditions, is a crucial factor for understanding the ability of species to cope with environmental changes. In Europe, agricultural intensification and the loss of forests have been major challenges for original forest dwellers, however some species, such as the European roe deer ( Capreolus capreolus), have been able to successfully colonize these new habitats. In this work, we investigated the adaptation of some digestive features of roe deer to the agricultural landscapes. We assessed whether changes in local landscape structure influenced the mass of both reticulorumen (RR) and distal fermentation chamber (DFC) of 47 juvenile and adult roe deer inhabiting an agro-ecosystem in southwest France. Woodland cover had a clear effect on diet quality (estimated by the rate of gas production of digestive contents) and DFC weight of animals. In fact, deer from the most forested landscapes showed heavier DFCs and fed on poorer quality diet (lower gas production) than their counterparts from the most open landscapes. RR mass was less influenced by the landscape openness, being the age of animals the main factor for understanding the variations of this digestive feature in our study area. We can conclude that colonizing agricultural landscapes increases the access to highly energetic and digestive resources. [ABSTRACT FROM AUTHOR]

Quantifying the self-thinning process in various plant communities has been a long-standing issue in both theoretical and empirical studies. Most studies on plant self-thinning have centered only on aboveground parts, and rarely on belowground parts. There is still a general lack of comparison between above- and belowground self-thinning processes, especially for forest communities. The fundamental mechanistic difference and the functional association between above- and belowground competition indicate that the self-thinning process of belowground parts may be different from that of aboveground parts. We investigated the self-thinning lines for above-ground ( M), below-ground ( M), and total biomass ( M), respectively, across forest communities in China. The results showed that neither the classical self-thinning rule (−3/2 exponent) nor the universal scaling rule (−4/3 exponent) can apply to all the self-thinning relationships across these forest communities and that the self-thinning lines for belowground biomass were flatter and lower than those for aboveground biomass across most of these forest communities. [ABSTRACT FROM AUTHOR]

Topographic niche differentiation (TND) is believed to facilitate the coexistence of tree species, but its effects are not well established for minor species or for life stages beyond recruitment. In this study, the effects of topography (slope inclination and topographic configuration) on the demographic parameters (mortality, diameter growth rate and recruitment rate) of both major and minor species in a species-rich temperate forest were examined using a mixed-model approach. The model selection analysis detected interspecies difference in the response of recruitment rate to topographic configuration. However, mortality and diameter growth rate of stems with DBH ≥ 5 cm did not show any species-specific response to two topographic parameters. The recruitment rate of major species tended to be higher under topographic conditions where many stems of the species already existed, suggesting significant habitat segregation. No such correlation was found for minor species. These results suggest TND has a limited effect on habitat segregation among species, and that other mechanisms also contributed to coexistence, especially when considering minor species. [ABSTRACT FROM AUTHOR]

There is a widespread belief that warmer climate forests suffer more folivory, as a proportion of leaf area, than cooler climate forests. However, there is a need for closely standardized studies to test this assumption. In this study, we estimated total folivory as percentage area damaged in freshly fallen, undecayed autumn leaves from the forest floor during the lifetime of deciduous tree leaves, using scanner-linked software. Over a period of 2 years, 154 samples were taken at 96 forested localities in eastern North America, spanning 17° of latitude. In terms of percentage area damage per leaf, the results in both years sampled suggest that there is significantly more damage in warmer, lower latitude areas of eastern North America. The decreasing folivory rate is higher in northern than in southern regions. The observations of a latitudinal trend may suggest that 'biotic' interaction is indeed more important in warmer temperate climates compared to cool temperate climates. [ABSTRACT FROM AUTHOR]

This work examines patches of Atlantic forests in Minas Gerais State where woolly spider monkeys ( Brachyteles hypoxanthus) are inhabitants in order to understand the effects of forest structure, diversity, and succession in B. hypoxanthus abundance. This study was carried out in three reserves: Rio Doce State Park (PERD), Mata do Sossego (Sossego), and Serra do Brigadeiro State Park (PESB). Structural studies were carried out by means of point-centered quarter samples in areas used by woolly spider monkeys. Evenness was lower in PERD than in the other two communities. By means of successional functional groups analysis and diametric structure, the PERD forest sample was shown to be in the later, and PESB forest sample in the earlier, stages of secondary succession. We found that tree species evenness and structural traits driven by succession were important factors in determining spider monkey abundance patterns. The PERD forest sample had lower evenness and had lower density of woolly spider monkeys than the Sossego forest sample. The lowest density of these primates was in the PESB forest sample, the earlier successional stage of secondary succession of this study. [ABSTRACT FROM AUTHOR]

We used survey data collected from a large plot (20 ha) of sub-tropical forest in the Dinghushan Nature Reserve, Guangdong Province, southern China, in 2005 to test the comparative performance of nine species-richness estimators (number of observed species, three species-individual curve models, five nonparametric estimators). As the true species richness, we used the 210 free-standing shrub and tree species of >1 cm diameter at breast height recorded during the survey. This true species richness was then used to calculate performance measures of bias, accuracy, and precision for each estimator, whereby we distinguished performance for low, medium, and high sampling intensity. Unsurprisingly, all estimators performed better than the number of observed species in terms of bias and accuracy. Surprisingly, however, two curve models ( logistic and logarithm) outperformed all other estimators in terms of bias, accuracy, and precision, which is in contrast to most other previous studies, in which nonparametric methods usually outperform curve models. Intriguingly, relative estimator performance changed between low, medium, and high sampling intensity, sometimes dramatically, reinforcing the assertion that the influence of sampling intensity on estimator performance is an important aspect to investigate and to consider when choosing estimators for ecological surveys. Because these results are based on only one dataset, the results should be treated with caution, both because (1) the generality of these results needs to be confirmed with simulated datasets and (2) more work is needed to establish what “true” species richness is extrapolated by each of the tested estimators in both the statistical and the practical sense. Nevertheless, the two curve estimators, namely Logistic and Logarithm, should be considered in future studies of comparative performance of species-richness estimators because of their outstanding performance in this study. [ABSTRACT FROM AUTHOR]

It is generally believed that tropical forests suffer more herbivory, as a proportion of leaf area, than do temperate forests. Reviews so far have compared studies performed by different authors using very different methodologies. Here we carried out studies on 125 samples at 86 localities in eastern North America and on 75 samples taken at five localities in Malaysia and Singapore, including both mature secondary and primary forest. Samples in North America were spread over 3 years. In tropical Asia, the samples were taken at four time slices at least 8 months apart, scattered over a 4-year period. Total herbivore damage during the lifetime of tree leaves was estimated from the percentage area damaged in recently fallen, undecayed leaves from the forest floor, using scanner-linked software. In terms of percentage damage per leaf, the results suggest that lowland tropical forest has significantly higher leaf herbivory (5.82%) than temperate forest (5.48%). This is in accord with the general expectation that aseasonal tropical forests should have more herbivory damage. However, when percentage damage ‘per unit time of growing season’ is calculated based on an estimate of leaf lifetime in the tropics, tropical lowland herbivory damage turns out to be a fraction (about one half) of that in the temperate zone. Thus, these results tend to put in question the widely held view that herbivore damage is markedly more intense in the tropics. Over total leaf lifetime, the intensity of damage in the tropical area is only slightly higher than temperate regions. In terms of intensity of herbivory on leaves per unit of time, the opposite seems to be the case. It is uncertain which index should be taken as more significant in interpreting the selection pressure for anti-herbivore defenses in the tropics. [ABSTRACT FROM AUTHOR]

We conducted a microcosm experiment for studying the decomposition of Altingia obovata leaf litter by the decomposer community at 20 and 30°C from three forest stands (namely a 35-year-old secondary forest, a 47-year-old secondary forest, and a primary forest) of a tropical montane rainforest. Our results showed that rank-order of the litter decomposition among the three forest stands was not parallel to the stand age. At 20°C, the mass loss of A. obovata leaf litter from the primary forest was higher than those from the two secondary forests, of which the younger stand showed higher mass loss than did the older one. However, there were no differences in mass loss among these three stands at 30°C. The mass loss for the two secondary forest stands, but not for the primary forest stand, increased significantly from 20 to 30°C. The level of lignin decomposition among the three stands at 20°C corresponded to their forest stand age, i.e., the primary forest > the 47-year-old secondary forest > the 35-year-old secondary forest. A rise of 10°C in temperature significantly increased lignin decomposition for the two secondary forests, while the reverse was true for the primary forest. Carbohydrate decomposition was positively related to the temperature but not to the stand age. The different responses of litter decomposition to the forest stand age and temperature might be due to the differences in the microbial activities among the three forest stands. [ABSTRACT FROM AUTHOR]

The effects of air pollution on the growth of mountain trees were investigated at Buna-daira (1,180 m a.s.l.), about half the way up Mt. Tateyama, located in Japan. Every year, about 1 million tourists are transported by highland buses through the Tateyama–Kurobe Alpine route. Since the route opened in 1971, some tree species along the road have declined and have been blighted, suggesting that bus exhaust was the cause. However, the level of regional and long-range transboundary air pollution has also increased significantly over the last few decades. The atmospheric NO2 concentration at the roadside in the forest was highly correlated with the traffic density of buses and penetration of the exhaust into the forest was detected. However, the maximum average NO2 concentration was lower than 3.5 ppbv during the peak traffic period in the year. At Buna-daira, the total stem cross-sectional area at breast height (BA) of the forest was nearly unchanged from 1999 to 2006, but the BA of Fagus crenata decreased 10% and that of Cryptomeria japonica increased 6%. Neither tree growth nor tree death was significantly correlated with distance from the road. The cause of the decline of F. crenata could not be attributed to the effects of road, i.e., air pollution emitted from the buses or edge effects of the road. This area was more affected by regional, long-range transport of air pollution (O3, SO2, etc.). The average atmospheric O3 concentration in autumn was higher than 40 ppbv and the recent increase in the O3 concentration may be an important factor of F. crenata decline through the changes in the interspecific relationships between F. crenata and C. japonica, O3 sensitive and tolerant species, respectively. [ABSTRACT FROM AUTHOR]

Old-growth forests consist of various types of small patches that reflect their own gap-forming process, which includes changes in environmental conditions occurring over several decades. We reconstructed the gap-forming processes that had occurred during a 40-year period for eight representative patches of an old-growth evergreen broad-leaved forest in Japan, and examined the current community structure. The selected patches were based on (1) changes in canopy heights estimated from aerial photographs taken in four different years, (2) long-term ecological research (LTER) monitoring records, and (3) a recent field survey, so that they sufficiently covered characteristic gap-forming processes such as a new gap, an old gap and consistently closed canopy. Height and diameter at breast height (DBH) were measured on all living trees taller than 1.3 m. In their height distributions, currently almost closed patches that were open in 1966 show a rotated sigmoid, whereas their DBH distributions are an inverse J-shape. In contrast, patches that have been consistently under a closed canopy exhibit gentle inverse J-shapes for both distributions. For species composition, there are no clear contrasts associated with the past gap-forming processes except for the existence of fast-growing deciduous species in large currently open patches. Our results suggested that the variation in several decades of gap-forming processes played a central role in the high patch diversity and the complex patch mosaic of the forest. Diverse gap-forming processes created micro-environmental heterogeneity both vertically and horizontally, and contributed to the maintenance of the species-rich, warm-temperate old-growth forest. [ABSTRACT FROM AUTHOR]

Relationships between microhabitat variables; understory light conditions in summer and winter, altitude, slope inclination and topographic categories (valley, ridge, and slope) and the distribution of Aucuba japonica Thunb. (Cornaceae), a common understory shrub species in Japan were examined using non-contagious 66, 20 × 20 m2 quadrats. The Morishita’s Iδ suggested that A. japonica distributions were strongly heterogeneous among the quadrats. Therefore positive spatial autocorrelation of A. japonica at a within-quadrat level (≤20 m) was obvious. Moran’s I statistics showed a significant positive spatial autocorrelation in A. japonica abundance within the distance shorter than 60 m. But the partial Mantel tests suggested that the mass effect from neighboring quadrats would little explain A. japonica abundance in a quadrat. The partial Mantel tests also clearly showed that A. japonica distributions were strongly structured by topography and understory light conditions. Using Monte Carlo randomization tests, we found that A. japonica was aggregately distributed in quadrats in valley which were covered by deciduous canopies. Better understory light conditions in winter together with valley edaphic conditions may increase the abundance of A. japonica there. It is concluded that habitat niche specialization is important in structuring distribution of A. japonica in this forest community. [ABSTRACT FROM AUTHOR]

We examined the effects of fragmentation of secondary broadleaf deciduous forests (secondary forests) on populations of the near-threatened butterfly, Sasakia charonda, in central Japan. Regression analyses revealed that the number of overwintering larvae per host tree significantly increased when the area of secondary forest patches and the Isolation Index of the forest patch increased and the distance from secondary forest patches containing the focal host trees to the nearest secondary forest patch decreased. There was a significantly positive correlation between the number of overwintering larvae and the number of host trees in the neighborhood. The host trees were primarily distributed at the edges of secondary forests. From the results of the backward elimination method of multiple linear regression analysis, independent variables other than patch area were eliminated, and the standardized partial regression coefficient of the patch area was significant. This result suggested that a contiguous distribution of large secondary forest patches with many host trees is very important to conserving this butterfly species. [ABSTRACT FROM AUTHOR]

The effects of local population density, sex morph [protogynous (PG) or protandrous (PA)], and individual tree size on the demographic processes of seed production were investigated in a heterodichogamous maple, Acer mono Maxim. var. Marmoratum (Nichols.) Hara f. dissectum, in a temperate forest of Japan. As the distance from conspecific reproductive adults increased, the percentage of immature seed fall and empty seeds increased significantly, indicating higher pollination success along with local population density. Although the difference was not distinct, pollination success was affected by the local population density of the reciprocal sex morph rather than that of both sex morphs. The trees at higher local population density sites suffered higher seed mortality due to predation and decay, and tended to produce smaller seeds. Thus, the impacts of local population density operated both positively and negatively on reproduction. As a factor of individual traits, tree size scarcely affected any demographic processes. On the other hand, sex morph did affect pollination success. Trees of PG type had lower immature seed fall than those of PA type, suggesting that the former has higher efficiency of pollen acceptance than the latter. The results on seed demography presented here partly support previous suggestions that heterodichogamous plants exhibit reciprocal cross-pollination and gender specialization as reproductive traits. [ABSTRACT FROM AUTHOR]

Fungi play a crucial role in the decomposition of lignin in fallen leaves but few studies have examined the functional roles of ligninolytic fungi associated with the decomposition of fallen leaves on tropical forest soils. This study examined fungal populations responsible for lignin decomposition in Castanopsis sieboldii leaves in a subtropical evergreen broad-leaved forest in southern Japan. Fallen leaves of C. sieboldii are characterized by the occurrence of bleached portions attributable to fungal colonization of leaf tissues and decomposition of lignin. The bleached area accounted for 29.7%, on average, of the total area of C. sieboldii fallen leaves in the study site. Leaf mass per unit area (LMA) and lignin content were lower in the bleached area than in the surrounding nonbleached area of the same leaves, indicating that removal of lignin enhanced mass loss from leaf tissues and created small-scale heterogeneity of decomposition within single leaves. An unidentified species of Lachnocladiaceae (Basidiomycetes) was isolated frequently from the bleached area and caused selective decomposition of lignin in leaves under pure culture conditions, indicating that this fungus was responsible for the bleaching. The greater hyphal length of basidiomycetes in the bleached area than in the nonbleached area supported the finding that this Lachnocladiaceae sp. was associated with the bleaching. The relatively rapid decomposition of C. sieboldii leaves on the subtropical forest soil is partly attributable to colonization of the litter by this Lachnocladiaceae sp. [ABSTRACT FROM AUTHOR]

We investigated the spatial distribution and growth of the Siberian dwarf pine ( Pinus pumila) in a valley–foothill larch–birch ( Larix cajanderi–Betula platyphylla as canopy trees) mixed forest of fire origin located in central Kamchatka with the aim of elucidating the ecological features of P. pumila when it is an undergrowth species in a forest. The spatial distribution of all individuals of all tree species was clumped, and the spatial distribution of the two canopy tree species did not repulsively affect that of P. pumila (i.e., its establishment site). These results suggest that the regeneration of P. pumila does not depend on canopy gaps. However, the analysis using a growth model indicated that the canopy trees negatively affected the growth of P. pumila and that the negative effect of L. cajanderi on P. pumila growth was stronger than that of B. platyphylla. The direction of the crown extension of P. pumila was weakly related to the open-space direction. Our results suggest that, although the spatial pattern of establishment of P. pumila is not repulsed by the distribution of canopy trees, the crown can spread horizontally toward the more sparsely populated areas of the canopy trees where they may have higher growth rates. [ABSTRACT FROM AUTHOR]

Species richness and abundance are the two most important diversity variables. Species abundance is additive when aggregated across spatial scale, whereas species richness is non-additive. This study analyzes the effect of spatial scale and site on species abundance and richness in a 25-ha temperate forest plot in the Changbai Mountains, northeastern China. The result shows that species abundance and richness are not only dependent on spatial scales, but also dependent on site. Species abundance responds linearly to changes of spatial scale with no intersection in different sites of the study area. However, although species richness also increases with the increase of spatial scale, there are some intersections for the different sites, suggesting that a species-rich site does not always have a high value if the spatial scale is changed. In all, with respect to additive variables, it is relatively easy to extrapolate them from one spatial scale to another spatial scale, as they and the spatial scale usually form a linear relationship. In contrast, non-additive variables are difficult to extrapolate across spatial scales, because they often respond nonlinearly to spatial scale changes. In order to extrapolate these non-additive variables across spatial scales, it is necessary to estimate the relationships between them and spatial scales. As a result, extrapolation of information among spatial scales may be possible, but very difficult, especially for non-additive variables. Because the 25-ha Changbai plot is very small compared to the extent of the world temperate forests, and the vegetation is a relatively uniform type, more such studies in other ecosystems are needed before theories and generalization about scaling effects can be formulated. [ABSTRACT FROM AUTHOR]

We attempted to obtain carbon sequestration maps of deciduous forests in Japan using detectable parameters from the Moderate Resolution Imaging Spectrometer (MODIS) sensor and to determine how the spatial pattern of carbon sequestration differs within the same forest ecosystem type. For this investigation, we firstly parameterized the MODIS algorithm at one flux tower site, Takayama, for the years 2002–2003. The MODIS algorithm could link flux-based net ecosystem productivity (NEP) with simple functions controlled by a thermal infrared band and a vegetation index. Second, the performance of the MODIS algorithm was validated through comparisons with the flux-based NEP at another flux tower site, Hitsujigaoka. The MODIS-based NEP at Hitsujigaoka was also within an accuracy of a flux-based NEP with R 2 of 0.879 and root mean square error of 1.64 gC m−2 day−1, regardless of canopy structure and age. The MODIS algorithm was noteworthy for its general applicability in different locations. Finally, we used the MODIS algorithm for the same forest ecosystem type in Japan for regional extrapolation of NEP. The MODIS-based NEP of deciduous forests in Japan showed great variance with 347 ± 288 gC m−2 year−1 in 2002, according to the stand structure and climatic condition of the year. Studies for quantification of ecosystem carbon balance need to consider variance, frequency and spatial distributions of NEP. Satellite remote sensing demonstrated the potential for the large-scale mapping of NEP. [ABSTRACT FROM AUTHOR]

To examine how early-emerging seedlings take advantage of establishment in a deciduous forest, we explored the relationships among the emergence date, growth stage and major causes of mortality (damping-off by fungi and predation by rodents) in seedlings of Fagus crenata. The emergence of current-year seedlings and their survival and damage were followed at short (3–7 days in early spring) intervals for a growing season. The growth stage was divided into two stages, with only cotyledons (CT stage) and with true leaves (TL stage). The survival rate was negatively correlated with the emergence date, indicating the advantage of early seedling emergence. This advantage was largely explained by the lower occurrence of damping-off. In contrast, seedling predation occurred independently of the emergence date, but depended strongly on the developmental stage. Rodents consumed a considerable number of seeds during the early period after emergence, and strongly preferred CT-stage over TL-stage seedlings throughout the growing season. Therefore, seedling predation was inferred to be concentrated in a relatively short period while the remaining seeds were depleted and CT-stage seedlings were abundant. The seedling stage synchronously shifted from the CT to TL stage. This growth-stage transition was independent of the emergence date and appeared to correspond with the timing of seed depletion. Delayed stage transition resulted in a disproportionately high risk of damping-off later in the season. Our results indicate that early seedling emergence is advantageous for F. crenata for resistance to pathogens and that the timing of growth-stage progression of seedlings appears important to escape predation because of the distinct food preference of predators. [ABSTRACT FROM AUTHOR]

Rates of nest predation have frequently been shown to differ between fragmented and unfragmented habitats, but have rarely been compared among natural habitats in the same geographic region. In this study, artificial nests of two types (open cup and domed) were placed in four habitats (mangroves, monsoon rainforests, eucalypt woodlands and paperbark swamps) over 12 months in three localities near Darwin in the Australian monsoon tropics to determine the effects of habitat, season and nest type on the rate of nest predation. A quail egg and a similarly coloured plasticine egg were placed in each nest. Habitat had a strong effect on nest predation rates, with nests in mangroves experiencing predation rates more than four times higher than those in eucalypt woodlands and paperbark swamps. Despite the strong rainfall seasonality of the region, there was no consistent seasonal variation in nest predation rates. Nest type also had little influence on predation rates, except in paperbark swamps where open cup nests suffered a higher predation rate than domed nests. The study indicates that generalised nest predation rates for tropical regions, even for small areas (e.g. <17 km radius), might overlook substantial variation between habitats. Such variation confounds purported differences in nest predation rates between tropical and temperate regions. [ABSTRACT FROM AUTHOR]

To clarify the habitat requirements of the near-threatened butterfly, Sasakia charonda (Lepidoptera, Nymphalidae), we studied the distribution pattern of its host trees, Celtis sinensis and Celtis jessoensis, and the utilization patterns of various vegetation types by this butterfly in the Oofukasawa River basin in Hokuto City, Yamanashi Prefecture, central Japan. Two species of host trees, C. sinensis and C. jessoensis (height = 2 m or more) were found in riparian forests on sandbanks (hereinafter, riparian forest), in forest regenerated after landslides on valley walls (landslide tracks), in secondary deciduous forests consisting mainly of Quercus acutissima or Quercus serrata and in forests established at abandoned paddy fields and their periphery, where weeds and shrubs used to be mown frequently to avoid shade on the paddies before their abandonment. This suggests that they are pioneer species, and their distribution and regeneration depend on natural and/or human disturbances. Host trees above 2 m were preferred by larvae, and there were very few such trees in secondary forests. More overwintering larvae occurred in riparian forests than at other sites. The number of S. charonda adults was highest at the edge of riparian forests, and we observed a variety of behaviors such as puddling, chasing and mating there. Although the number of adult butterflies was smaller inside and at the edge of secondary forests than in riparian forests, puddling by males and roosting on the trunk of Q. acutissima or Q. serrata by females were observed more frequently there than in riparian forests. Thus, we conclude that landscapes including both riparian forests with natural disturbance and secondary forests with Quercus trees are necessary to maintain host Celtis trees and S. charonda populations. [ABSTRACT FROM AUTHOR]

Forest fragmentation in tropical ecosystems can alter nutrient cycling in diverse ways. We have analysed the effects of the forest-pasture edge on nutrient soil dynamics in a tropical deciduous forest (TDF) in Mexico. In two remnant forest fragments, both larger than 10 ha, litterfall, litter and soil samples associated to the tree Caesalpinia eriostachys were collected at five distances from the pasture edge into the inner forest (10 m in the pasture and 0–10, 30–40, 70–80 and 100–110 m towards the forest interior). We measured the concentrations of carbon (C), nitrogen (N) and phosphorus (P) in litterfall, surface litter and soil, and soil microbial C (Cmic) and microbial N (Nmic). Soil nutrient concentrations and Cmic and Nmic were lower in the pasture soils than in the forest soil samples. Total C and N pools, and Cmic and Nmic in the pasture were lower than in the forest. In contrast, net N immobilization and the increase in Nmic from rain to dry season increased from the edge to the inner forest. Soil P concentration was lower in the pasture and at the first distance class in the forest margin (0–10 m) than in the sites located further into the forest, while litter P concentration had the inverse pattern. Litterfall P was also reduced near the edge and increased towards the forest interior. As a consequence, litterfall C:P and N:P ratios decreased from the edge to the inner forest. These results suggest that the forest–pasture edge disrupts P dynamics within the first 10 m in the forest. Thus, plants' use of nutrients and productivity could be altered in the edge of fragmented forests. [ABSTRACT FROM AUTHOR]

Two types of tagging methods, i.e., a 1 × 3-cm tin tag attached to seed with a 10- to 12-cm metal wire (total weight 0.32 g) and a 2 × 4-cm white plastic tag fastened to seed with an identical metal wire (total weight 0.57 g) were used to study their effects on seed dispersal of Korean pine by small rodents. A total of 600 seeds were released to assess four main points: (1) difference in seed survival rates, (2) difference in caching behaviors of small rodents, (3) difference in dispersal distances, and (4) proportion of seed missing. The results demonstrated that seed removal for wire-plastic-tagged seeds was faster than that for wire-tin-tagged seeds. There was no apparent difference in the proportion of seeds eaten in situ (42% and 52% for wire-plastic-tagged seeds and wire-tin-tagged seeds, respectively). We found 41% and 1% of seeds were moved and hoarded for wire-plastic-tagged seeds and wire-tin-tagged seeds, respectively. However, 2.33% and 14% of seeds were missing, and their ultimate fates were not known for wire-plastic-tagged seeds and wire-tin-tagged seeds, respectively. We found the wire-plastic-tagged seeds easier to track than the wire-tin-tagged seeds due to the fact that the white plastic tags were more salient than the tin tags in field environments. The average dispersal distances were 4.11 ± 2.40 m and 3.01 ± 2.06 m for wire-plastic-tagged seeds and wire-tin-tagged seeds, respectively, and showed great difference. Despite most being eaten in situ or after removal, 41% of seeds were cached for wire-plastic-tagged seeds, much more than for wire-tin-tagged seeds. A total of 71 primary caches (123 seeds) were found for wire-plastic-tagged seeds, with the average and maximum cache sizes being 1.73 and 6, respectively. However, only three caches were found, and cache size was equal to one for wire-tin-tagged seeds. The above data suggests there is some uncertainty in different tagging methods to used track seed fates. Despite their effectiveness in helping to trace seed dispersal or movement by seed-dispersing rodents, different tagging methods—including size, color, and mass—need to be fully understand in enclosure experiments . [ABSTRACT FROM AUTHOR]

Quantitative food webs were constructed to explore the community structure of leaf-mining moths in the family Gracillariidae and their parasitoid wasps in a deciduous forest in Hokkaido, Japan. A whole food web was constructed from data collected from June to October 2001. In the web, 16 leafminer species on seven tree species were attacked by 58 species of hymenopteran parasitoid; 376 links between leafminers and parasitoids were observed. Leafminers were specialist herbivores, but most parasitoids were generalists. Five webs were constructed for the seasonal prevalence of leafminers over the one-year period to reveal the temporal dynamics in community structure. Among the seasonal webs, the first web in June was distinctive because two tree species, Japanese umbrella tree Magnolia obovata and Japanese magnolia M. kobus, supported the community. Second to fourth webs from July to September were dominated by the leafminer species on Japanese oak Quercus crispula, and the fifth web was marked by that on Carpinus cordata. The extent of potential apparent competition among leafminers was evaluated using quantitative parasitoid overlap diagrams. These diagrams suggested that abundant host species are likely to have large indirect effects on less abundant species. Moreover, the potential for apparent competition between leafminer species inhabiting different host tree species can occur, although leafminers sharing the same tree species are prone to interact via shared parasitoids. In this system, particular leafminer species, acting as potential sources of apparent competition, can affect other species as sinks, and control whole-community dynamics. Directed apparent competition may potentially occur around oak trees. [ABSTRACT FROM AUTHOR]

The effects of simulated N deposition on changes in mass, C, N and P of decomposing pine ( Pinus massoniana) needles in a disturbed and a rehabilitated forest in tropical China were studied during a 24-month period. The objective of the study was to test the hypothesis that litter decomposition in a disturbed forest is more sensitive to N deposition rate than litter decomposition in a rehabilitated forest due to the relatively low nutrient status in the former as a result of constant human disturbance (harvesting understory and litter). The litterbag method and N treatments (control, no N addition; low-N, 5 g N m−2 year−1; medium-N, 10 g N m−2 year−1) were employed to evaluate decomposition. The results revealed that N addition increased (positive effect) mass loss rate and C release rate but suppressed (negative effect) the release rate of N and P from decomposing needles in both disturbed and rehabilitated forests. The enhanced needle decomposition rate by N addition was significantly related to the reduction in the C/N ratio in decomposing needles. However, N availability is not the sole factor limiting needle decomposition in both disturbed and rehabilitated forests. The positive effect was more sensitive to the N addition rate in the rehabilitated forest than in the disturbed forest, however the reverse was true for the negative effect. These results suggest that nutrient status could be one of the important factors in controlling the response of litter decomposition and its nutrient release to elevated N deposition in reforested ecosystems in the study region. [ABSTRACT FROM AUTHOR]

We report here the results of an 8-year study of the growth and population dynamics of Quercus mongolica ssp. crispula in a Pinus densiflora stand in a state of succession. In 1998, there were 169 Q. mongolica ssp. crispula individuals in a 400-m2 plot under the P. densiflora canopy. This number remained nearly constant between 1998 and 2005. Mean recruitment of new individuals was 11 year−1, while mean mortality was 12 year−1. Of the 35 individuals ≥60 cm in height existing in 1998, 30 were still surviving in 2005. We were able to represent the height growth of Q. mongolica ssp. crispula individuals as H=30 [1+21.96 exp(−0.0839 t)]−1, with t = years since 1998 and H = height in meters. Using this equation we predict that by 2015 the mean height of Q. mongolica ssp. crispula trees in the stand will exceed those of understory trees, such as Rhus trichocarpa and Prunus maximowiczii. Once above the understory stratum, the Q. mongolica ssp. crispula trees can be expected to grow more rapidly due to the better light conditions, thereby rapidly reaching the canopy stratum of the P. densiflora stand. [ABSTRACT FROM AUTHOR]

In pursuance of economic growth and development, logging has exhausted the natural timber resource in the tropical rainforest of Sabah, Malaysia. Realizing the forest depletion, the Sabah Forestry Department, with technical support from the German Agency for Technical Cooperation, begun developing a management system with the intent of managing all commercial forest reserves in a way that mimics natural processes for sustainable production of low volume, high quality, and high priced timber products in 1989. As dictated by a forest management plan based on forest zoning, about 51,000 ha of the entire area is set aside for log production and 4,000 ha for conservation in Deramakot Forest Reserve, Sabah, Malaysia. This Forest Management Plan has served as the blueprint for operational work and biodiversity conservation in Deramakot to the present. A strict protection area is set aside for biodiversity conservation within the reserve. A reduced-impact logging system is being employed for harvesting with minimal impacts on the physical environment. Deramakot Forest Reserve was certified as “well managed” by an international certification body, the Forest Stewardship Council, in 1997 and is the first natural forest reserve in Southeast Asia managed in accordance with sustainable forestry principles. In addition to providing a "green premium," certification provides easier market access, evidence of legality, multi-stakeholder participation, conservation of biodiversity and best forest management practices, particularly reduced-impact logging techniques. Deramakot Forest Reserve is the flagship of the Sabah Forestry Department and serves as a symbol of what can be achieved with political support and institutional commitment. [ABSTRACT FROM AUTHOR]

We examined the basal area of two life forms (conifers vs. broadleaf trees) along elevational gradients on Yakushima Island, Japan and on two series of geological substrate on Mount Kinabalu, Borneo. On Yakushima, total stand basal area abruptly increased from 700 to 1,050 m in accordance with the high dominance of conifers, indicating the presence of additive basal area of conifers in conifer–broadleaf mixed forests at higher elevations (1,050–1,300 m). Along two substrate series on Kinabalu, some forests at higher elevations (1,860–3,080 m) showed relatively high dominance of conifers, but conifer basal area did not appear to be additive. Conifers were emergents above the canopy of broadleaf trees in mixed forests on Yakushima, but two life forms usually coexisted in the single-story canopy in mixed forests on Kinabalu. Litterfall rate as a surrogate of productivity decreased with decreasing temperature along elevation on both the sites, but the rate of decrease was slower on Yakushima, where mixed forests at higher elevations showed relatively high rates. Thus, we suggest that additive basal area of conifers was linked to their emergent status, and that it enhanced productivity by complementary use of light by two life forms that occupy different stories. On Yakushima, typhoons are a major disturbance, but do not severely limit the height growth of conifers, allowing the development of two-story mixed forests. On Kinabalu, a major disturbance is El Niño-driven drought, and hydraulic limitation to tree height may explain the non-additive and non-emergent nature of conifers. [ABSTRACT FROM AUTHOR]

We combine ecological and economic dynamics to study the management of a natural resource that supports both ecosystem and human needs. Shrinking the resource base introduces a threat of occurrence of catastrophic ecological events, such as sudden ecosystem collapse. The occurrence conditions involve uncertainty of various types, and the distinction among these types is important for optimal resource management. When uncertainty is due to our ignorance of some aspects of the underlying ecology, the isolated equilibrium states characterizing optimal exploitation for many renewable resource problems become equilibrium intervals. Genuinely stochastic events shift the optimal equilibrium states, but maintain the structure of isolated equilibria. [ABSTRACT FROM AUTHOR]

Coarse woody debris (CWD) is an essential component of forests. However, quantification of both the mass and nutrient content of CWD within a given environment tends to be a fairly labor-intensive proposition that requires long-term studies to be conducted for viable data to be obtained. As a result, various aspects of CWD in forest ecosystems remain somewhat poorly understood. In this review, we have compiled all available estimates of CWD mass and nutrients from both coniferous and deciduous forests in Korea. The CWD mass data varied substantially by forest type, age, location, and sampling time, ranging from 1.5 to 24.5 Mg ha−1, and for the amount (kg ha−1) of nutrients in the CWD, ranging from 3.5 to 23.6 for nitrogen (N), 0.8 to 4.7 for phosphorus (P), 3.9 to 13.3 for potassium (K), 25.9 to 30.9 for calcium (Ca), 1.4 to 4.2 for magnesium (Mg), and 0.1 to 0.6 for sodium (Na). The mass of CWD transferred from live trees to the forest floor ranged between 0.1 and 4.9 Mg ha−1 year−1, and these values were roughly equivalent to 26–42% of the annual litterfall inputs (2.5–10.8 Mg ha−1 year−1) for mixed Quercus spp. forests within the relevant region. Annual nutrients inputs (kg ha−1 year−1) through CWD decomposition were 0.7–1.6 for N, 0.04–0.3 for P, 0.3–1.0 for K, 1.7–3.1 for Ca, and 0.1–0.3 for Mg. Consequently, these results revealed that the ecological value of CWD for C and nutrient cycling was relatively insignificant. However, only a limited number of studies have been conducted on CWD in different coniferous or mixed deciduous forests in the region. As a direct result of this paucity of data, further long-term studies on CWD mass and nutrients in a variety of forest types are required in order to be able to evaluate accurately the ecological value of CWD on biodiversity and physical properties in Korean forest ecosystems. [ABSTRACT FROM AUTHOR]

Labrador, Canada is the last relatively undeveloped landmass of Boreal and subarctic Canada. Its land area is over 288,000 km2, with less than 1% developed, and a human population of below 30,000. Labrador is greater than 60% forest- and woodland-covered and over 30% tundra, soil and rock barrens. We review the ecology and distribution of forests, woodlands, and related vegetation of Labrador within the context of climate, forest site index, landform, soils, and disturbance. Recent ecosystem management through a public planning process with emphasis on past and future comanagement and development with traditional and western scientific principles is currently underway. Plant–animal interactions, traditional uses by aboriginal groups, and early history are also reviewed. [ABSTRACT FROM AUTHOR]

We evaluated relative density indices of sika deer ( Cervus nippon) to aid in population management. We monitored sika deer population trends from 1992 to 2002 in the eastern part of Hokkaido Island, northern Japan, using spotlight surveys, aerial surveys, catch per unit effort (CPUE), sighting per unit effort (SPUE), and cost of damage to agriculture and forestry. We assumed that the artificial bias in the spotlight index would be lower than in other indices, and compared temporal patterns of other indices to those produced using spotlight surveys using model II regression. There was a significant correlation between the damage cost index and the spotlight index, and both indices indicated consistent population trends. Managers used CPUE as a tool to determine hunting quota efficiency. The SPUE index had the smallest standard error among the indices, and the spotlight survey index had the second smallest standard error. Overall, the spotlight survey was the most useful index because its estimate error was small and it was precise in showing population trends; however, spotlight surveys did lead to underestimation once in 1994. The SPUE index seems to be effective in checking the validity of the spotlight index, but there are so many environmental and demographic uncertainties that several independent indices should be used and crosschecked for accurate evaluation of population trends. [ABSTRACT FROM AUTHOR]