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1.
This data paper reports litter fall data collected in a network of 21 forest sites in Japan. This is the largest litter fall 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. Twenty-three permanent plots in which usually 25 litter traps were installed were established in old-growth or secondary natural forests. Litter falls were collected monthly from 2004, and sorted into leaves, branches, reproductive structures and miscellaneous. The data provide seasonal patterns and inter-annual dynamics of litter falls, and their geographical patterns, and offer good opportunities for meta-analyses and comparative studies among forests.  相似文献   

2.
This data paper reports census data of ground-dwelling beetle and other fauna of the forest floor environment; collections were made from a network of 22 forest sites in Japan. To our knowledge, this represents the largest dataset for long-term monitoring of a ground-dwelling beetle community and other taxa in a ground environment in forests, which covers a broad climatic range in the temperate zone and is freely available. The network forms part of the Monitoring Sites 1000 Project launched by the Ministry of the Environment, Japan. It covers subalpine, cool- and warm-temperate and subtropical climatic zones and the four major forest types of Japan. Thirty-three permanent plots usually 1 ha in size were established in old-growth, secondary natural and a few plantation forests. Censuses of the ground-dwelling beetle community were conducted using pitfall trapping and forest floor environment monitoring every year from 2004 to the present. During the initial 9 years of the census (2004–2012), 59,762 beetle individuals (including 3182 larvae) of more than 314 species were recorded. This dataset includes taxonomy and biomass of each beetle individual and each taxonomic group of other invertebrates coincidently captured in pitfall trapping. The dataset also includes data related to ground coverage by forest floor vegetation, dry mass of the accumulated organic litter layer, and carbon and nitrogen contents and cellulose decomposition rate in organic layer and surface mineral soil. The data could be used to investigate geographical patterns and intra- and inter-annual dynamics of individual body mass, populations and community structures of ground-dwelling beetles, and their relationships with the forest floor environment. Furthermore, the data could be analyzed with other open datasets related to tree community dynamics and litter fall continuously measured in the same study plots. This dataset also provides information related to the distribution and average body mass of each beetle species.  相似文献   

3.
Research in large, long-term tropical forest plots   总被引:2,自引:0,他引:2  
The past 15 years has seen the creation oflarge (>/16 ha) permanent inventory plots in each of the major tropical forest formations of the world. Currently, six such plots have been fully mapped, and five more and under way. A standardized methodology is used at all sites - a complete census of all trees and saplings down to 1 cm in diameter - thus assuring strict comparability between sites and allowing the development of general models for the dynamics of tropical forests. The inventories aim to gather demographic information on individual tree species, to provide long-term information on forest composition so that future changes can be detected, to estimate the economic value of forest resources, to generate models of sustainable extraction, and to provide data on underused native species for use in reforestation or plantation forestry. The plots also provide data from undisturbed forest to serve as a control for anthropological and management studies of harvested forests.  相似文献   

4.
《农业工程》2023,43(1):106-111
The present study reports the seed dispersal modes of tree species and their relationship with altitudinal gradient from six tropical forests of Eastern Ghats located in India. Anemochory, autochory and zoochory are the three major types of seed dispersal modes recognized for the 272 tree species recorded from a total of 120 0.5 ha area. The predominant dispersal mode is zoochory with 58% of the total tree abundance and 69% of total species richness, followed by autochory with 30% and 19%, and anemochory 12% and 12%, respectively. One way ANOVA revealed that the species richness as well as tree abundance of the three dispersal modes varied significantly across the six tropical forest sites. Regression analysis revealed that both the tree species richness and abundance of zoochory dispersal mode had positive relation with altitude of forest location, while, no such relation was observed for the other two dispersal modes. This study shows that the zoochory increases in species richness and tree abundance with increasing altitude. This may be attributed to high rainfall supporting evergreen forest types with high ratio of animal dispersed tree species in forests at high altitude. However, further studies on these aspects are warranted to draw a significant statement. The predomination of zoochory dispersal mode in this study is comparable with earlier studies in tropical forests elsewhere.  相似文献   

5.
The aboveground wood biomass (AWB) of tropical forests plays an important role in the global carbon cycle, and local AWB estimates provide essential data that enable the extrapolation of biomass stocks to ecosystem or biome-wide carbon cycle modelling. Few AWB estimates exist in Neotropical freshwater floodplains, where tree species distribution and forest structure depend on the height and duration of periodic inundations. We investigated tree species composition, forest structure, wood specific gravity, and AWB of trees ≥10 cm dbh in 16 plots totalling an area of 1 ha in a seasonally inundated riparian forest of the lower Miranda River, southern Pantanal, Brazil. The 443 tree individuals belonged to 46 species. Four species (Inga vera, Ocotea suaveolens, Tabebuia heptaphylla and Cecropia pachystachya) comprised more than 50% of the Total Importance Values (TIV), and floristic similarities between the plots averaged 38%. Although we detected an overall increase in species diversity correlated with decreasing flood levels, the most important tree species had almost identical distribution patterns along the flooding gradient. The stand basal area per plot (±?s.d.) amounted to 3.0?±?1.1 m2 (47.8?±?18.1 m2/ha), and the tree heights averaged 10.9?±?1.4 m. Multiplying the individual basal areas by individual tree heights and a form factor of 0.6, we estimated the aboveground wood volume (AWV) for each individual, and for each plot (24.4?±?11.7 m3, 391.1?±?188 m3/ha). Wood specific gravity (SG) varied between 0.39 g/cm3 (Cecropia pachystachya) and 0.87 g/cm3 (Tabebuia heptaphylla), with a stand level average of 0.63?±?0.12 g/cm3. Multiplying the individual AWV with species SG, we estimated the plot AWB to be 16.2?±?6.4 Mg (259.4?±?102 Mg/ha). This value is comparable to that reported for late-successional forest stands of Amazonian floodplain forests, and it is close to the worldwide tropical average AWB. Because tree heights in the present forest were comparatively low when compared to other Neotropical forests, we found that resprouting of stems accounted for comparatively high basal areas. We argue that stem resprouting is an adaptation of tree species originating in non-flooded Cerrado to the seasonal inundations of riparian forests.  相似文献   

6.
In Japan, the impacts of human disturbance on ant assemblages have been intensively studied mainly in suburban areas. In contrast, the impact on ant assemblages of long-term human management and abandonment of forests is not well studied even though forestry is viewed as a process that seriously impacts ant assemblages. Besides, the studies focused on the relationship between secondary forest management for producing the firewood and charcoal which is considered to be characteristic of Japan and ant assemblage is not well studied. Do the long-term impacts on the secondary forest alter the ant composition? The effects of forest management on ant assemblages were studied through comparisons of managed, unmanaged and clear cut forest plots in secondary tree stands that had been used previously for producing firewood and charcoal. Ant species richness did not differ among forest categories, but ant species composition varied among forest categories. The absence or presence of openland and woodland ant specialist species is considered a good indicator for secondary forest management.  相似文献   

7.
? Linking tree diversity to carbon storage can provide further motivation to conserve tropical forests and to design carbon-enriched plantations. Here, we examine the role of tree diversity and functional traits in determining carbon storage in a mixed-species plantation and in a natural tropical forest in Panama. ? We used species richness, functional trait diversity, species dominance and functional trait dominance to predict tree carbon storage across these two forests. Then we compared the species ranking based on wood density, maximum diameter, maximum height, and leaf mass per area (LMA) between sites to reveal how these values changed between different forests. ? Increased species richness, a higher proportion of nitrogen fixers and species with low LMA increased carbon storage in the mixed-species plantation, while a higher proportion of large trees and species with high LMA increased tree carbon storage in the natural forest. Furthermore, we found that tree species varied greatly in their absolute and relative values between study sites. ? Different results in different forests mean that we cannot easily predict carbon storage capacity in natural forests using data from experimental plantations. Managers should be cautious when applying functional traits measured in natural populations in the design of carbon-enriched plantations.  相似文献   

8.
Gap regeneration was studied in a typical primary evergreen broad-leaved forest withoutDistylium racemosum, at the Kasugayama Forest Reserve, southwestern Japan and the results were compared with those from other primary evergreen broad-leaved forests in southwestern Japan, whereD. racemosum was the dominant species. Several common types of gap regeneration behavior were recognized among the major tree species and forests with or withoutD. racemosum consisted of three typical regeneration guilds which could be detected in the principal component analysis.Castanopsis cuspidata frequently regenerated in gaps from saplings recruited before gap formation in the forest withoutD. racemosum, although elsewhere, in forests withD. racemosum, it lacked advanced regeneration and regenerated in gaps from saplings recruited after gap formation. Some evergreenQuercus had their regenerations in gaps of the forest withoutD. racemosum, although elsewhere, in forests withD. racemosum, evergreenQuercus might not regenerate. The results indicate that tree species may change their regeneration behavior depending on the presence or absence of another key dominant species. This suggests that the presence and the dominance of a potential competitor induces shifts in the regeneration niche of other coexisting tree species.  相似文献   

9.
The most diverse tree communities on earth, the tropical wet forests, to a large degree remain ecological enigmas. What accounts for the coexistence of 100 or more tree species per hectare, compared to the 15 or fewer found in most temperate forests? What are the lifespans of tropical forest trees? What factors control their populations through time and space? Do the different species have highly individual regeneration patterns, or are many in fact ecological equivalents? Although we are far from having satisfactory answers to these questions, recent studies of regeneration processes are leading toward new interpretations of these complex communities.  相似文献   

10.
Tree communities of secondary deciduous oak forests were surveyed in 13 forests (two in residential and 11 in rural areas) in the warm temperate Hokuriku District of Japan to understand the effects of fragmentation, location (residential or rural), and logging history. The rural forest logged most recently, where diameter at breast height was smallest, had a distinct canopy tree (>12 m) community due to an increase of trees from wind-dispersed seeds. The rural forest with gaps and the two residential forests also had different canopy tree communities from the other rural forests. In contrast, the tree community in the shrub layer (≤6 m) was not influenced by logging history and the existence of gaps but by location only. This was caused by an increase in evergreen trees (consequently causing poor light conditions on the forest floor) and a decrease in trees from wind-dispersed seeds in the residential forests. Among the rural forest patches, no negative effects of forest size and isolation on density of tree individuals were detected for any seed dispersal mode. This may be because many forest patches were arranged at distances of 10–50 m from neighboring patches in rural areas, which enables tree species with low dispersal ability to disperse their seeds to neighboring forests. However, as found in the residential forests, long-term abandonment and extensive fragmentation may gradually reduce tree diversity through loss of tree species with shade intolerance and low seed dispersal ability.  相似文献   

11.
云南宁蒗县小凉山的三尖杉林   总被引:3,自引:0,他引:3  
本文报道滇西北宁蒗县的三尖杉天然森林群落的特征和树种。这种森林分布于海拔2300—2500米的喀斯特河谷。具有两个乔木层,其中乔木亚层是优势层,由三尖杉组成。林内共有58科84属95种维管束植物。主要是喜钙的和湿润生的生态类型。森林生态的和植物群落的特征反映出森林从亚热带向暖温带的过渡性。同时,该林具有较好的自然更新能力。  相似文献   

12.
This study examined historical census data to evaluate the vulnerability of major tall-tree species in northern Japan to strong winds. Intensive data, which measured more than 20,000 damaged trees (defined as trees that were killed or lost their major crown) in >500 ha of a natural mixed forest, were collected immediately after a severe typhoon in 1954. More than half of the damaged trees had been uprooted, and the negative size-dependency was found for the proportion of uprooting throughout species. Simple correlation analyses with respect to the averaged species-specific characteristics suggested that tree species with a high crown-depth/height tended to uproot (against to stem breakage) in a size-class with diameter at breast height 30–50 cm. Although the census data had yielded no information about non-damaged trees, the estimation of pre-disturbed stand (based on 63 1-ha plot data together with aerial photographs and GIS) revealed that the observed damage reached ca. 25% in terms of basal area. The proportion of damaged trees seemed to be doubled among species (15–42% in basal area). A higher proportion of uprooting, which indicates a large supply of tip-up mounds, and mixture of less vulnerable species, might contribute to recovery process after a wind disturbance in this type of mixed forests.  相似文献   

13.
Restoration should be a part of an overall strategy for national, regional and local land management, rather than an independent action. A hierarchically structured approach for restoration is examined by introducing actual policy and work for reestablishment of natural forest in Tokushima Prefecture, Shikoku, Japan. The goal set by Tokushima Prefectural Government is to increase the quality of biotope for indigenous plants and animals through increasing the area of natural and semi-natural vegetation and their connectivity. A networking map indicating high priority areas to be conserved or to be restored has been produced, using Natural Environment GIS provided by the Ministry of Environment of Japan. Having the estimated distribution of natural forests is helpful for selecting the targets for restoration, because natural forests have already disappeared from most regions due to land development. For reforestation at the cutover site, a method for designing work was developed. In order to select species and plan planting zones, ecotope types were identified both in natural forest as a reference and at the cutover site. A system for supplying indigenous seedlings was established.  相似文献   

14.
Tree‐holes provide an important microhabitat that is used for feeding, roosting and breeding by numerous species around the world. Yet despite their ecological importance for many of New Zealand's endangered species, few studies have investigated the abundance or distribution of tree‐holes in native forests. We used complementary ground and climbed tree surveys to determine the abundance, distribution and characteristics of tree‐holes in undisturbed Nothofagus forest in the Lewis Pass, New Zealand. We found that hole‐bearing trees were surprisingly abundant compared with many other studies, including Australian Eucalyptus species and American beech. In fact, we estimated as many as 3906 tree‐holes per hectare, of which 963 holes per hectare were potentially large enough to provide roost sites for hole‐nesting bats in New Zealand, while only eight holes per hectare were potentially suitable for specialist hole‐nesting birds. This was of great interest as primary cavity‐excavating animals are absent from New Zealand forests, compared with North America and Australia. Moreover, tree‐hole formation in New Zealand is likely to be dominated by abiotic processes, such as branch breakage from windstorms and snow damage. As has been found in many other studies, tree‐holes were not uniformly distributed throughout the forest. Tree‐holes were significantly more abundant on the least abundant tree species, Nothofagus fusca, than on either N. menziesii or N. solandri. In addition to tree species, tree size was also an important factor influencing the structural characteristics of tree‐holes and their abundance in this forest. Moreover, these trends were not fully evident without climbed tree surveys. Our results revealed that ground‐based surveys consistently underestimated the number of tree‐holes present on Nothofagus trees, and illustrate the importance of using climbed inspections where possible in tree‐hole surveys. We compare our results with other studies overseas and discuss how these are linked to the biotic and abiotic processes involved in tree‐hole formation. We consider the potential implications of our findings for New Zealand's hole‐dwelling fauna and how stand dynamics and past and future forest management practices will influence the structural characteristics of tree‐holes and their abundance in remnant forest throughout New Zealand.  相似文献   

15.
Hunting affects a considerably greater area of the tropical forest biome than deforestation and logging combined. Often even large remote protected areas are depleted of a substantial proportion of their vertebrate fauna. However, understanding of the long‐term ecological consequences of defaunation in tropical forests remains poor. Using tree census data from a large‐scale plot monitored over a 15‐year period since the approximate onset of intense hunting, we provide a comprehensive assessment of the immediate consequences of defaunation for a tropical tree community. Our data strongly suggest that over‐hunting has engendered pervasive changes in tree population spatial structure and dynamics, leading to a consistent decline in local tree diversity over time. However, we do not find any support for suggestions that over‐hunting reduces above‐ground biomass or biomass accumulation rate in this forest. To maintain critical ecosystem processes in tropical forests increased efforts are required to protect and restore wildlife populations.  相似文献   

16.
1.?Species diversity of arboreal arthropods tends to increase during rainforest succession so that primary forest communities comprise more species than those from secondary vegetation, but it is not well understood why. Primary forests differ from secondary forests in a wide array of factors whose relative impacts on arthropod diversity have not yet been quantified. 2.?We assessed the effects of succession-related determinants on a keystone ecological group, arboreal ants, by conducting a complete census of 1332 ant nests from all trees with diameter at breast height?≥?5?cm occurring within two (unreplicated) 0·32-ha plots, one in primary and one in secondary lowland forest in New Guinea. Specifically, we used a novel rarefaction-based approach to match number, size distribution and taxonomic structure of trees in primary forest communities to those in secondary forest and compared the resulting numbers of ant species. 3.?In total, we recorded 80 nesting ant species from 389 trees in primary forest but only 42 species from 295 trees in secondary forest. The two habitats did not differ in the mean number of ant species per tree or in the relationship between ant diversity and tree size. However, the between-tree similarity of ant communities was higher in secondary forest than in primary forest, as was the between-tree nest site similarity, suggesting that secondary trees were more uniform in providing nesting microhabitats. 4.?Using our rarefaction method, the difference in ant species richness between two forest types was partitioned according to the effects of higher tree density (22·6%), larger tree size (15·5%) and higher taxonomic diversity of trees (14·3%) in primary than in secondary forest. The remaining difference (47·6%) was because of higher beta diversity of ant communities between primary forest trees. In contrast, difference in nest density was explained solely by difference in tree density. 5.?Our study shows that reduction in plant taxonomic diversity in secondary forests is not the main driver of the reduction in canopy ant species richness. We suggest that the majority of arboreal species losses in secondary tropical forests are attributable to simpler vegetation structure, combined with lower turnover of nesting microhabitats between trees.  相似文献   

17.
We compared forest gardens, or tembawang, in twoareas in West Kalimantan, Indonesia, to patches of primary forest in terms ofsuccessional stage, mode of dispersal and characteristics of human use ofnon-planted tree species. This information was acquired for 144 tree speciesinventoried in six tembawang forest gardens and two intactnatural forest patches, through interviews at the site and a survey of theliterature. In particular older tembawang were found tohave practically the same proportions of species of different successionalstages and modes of dispersal as natural forests, thus emphasising the potentialof tembawang in conserving tree species. Non-planted treespecies of tembawang and natural forests also havepractically indistinguishable spectra of human uses, indicating that themanagement of these tembawang does not significantlydiscriminate between species with certain uses. However, we also identified twoaspects that should be taken into account in considering the conservation roleof tembawang. The floras of the two study areas showedsignificant regional differentiation, implying that efficient conservation inWest Kalimantan needs to have a rather dense network. We also found that latesuccessional species and animal-dispersed species oftembawang were more commonly geographically widespread thanspecies of the same ecological characteristics found in natural forests. Thus,even if tembawang are similar to natural forests in termsof numbers of species with different ecological characteristics, the compositionof non-planted tree species in tembawang is not a randomsample from natural forest, but overrepresents species that are easily dispersedand/or established.  相似文献   

18.
Tracking the response of forest ecosystems to climate change demands large (≥1 ha) monitoring plots that are repeatedly measured over long time frames and arranged across macro-ecological gradients. Continental scale networks of permanent forest plots have identified links between climate and carbon fluxes by monitoring trends in tree growth, mortality and recruitment. The relationship between tree growth and climate in Australia has been recently articulated through analysis of data from smaller forest plots, but conclusions were limited by (a) absence of data on recruitment and mortality, (b) exclusion of non-eucalypt species, and (c) lack of knowledge of stand age or disturbance histories. To remedy these gaps we established the Ausplots Forest Monitoring Network: a continental scale network of 48 1 ha permanent plots in highly productive tall eucalypt forests in the mature growth stage. These plots are distributed across cool temperate, Mediterranean, subtropical and tropical climates (mean annual precipitation 850 to 1900 mm per year; mean annual temperature 6 to 21°C). Aboveground carbon stocks (AGC) in these forests are dominated by eucalypts (90% of AGC) whilst non-eucalypts in the understorey dominated species diversity and tree abundance (84% of species; 60% of stems). Aboveground carbon stocks were negatively related to mean annual temperature, with forests at the warm end of the temperature range storing approximately half the amount of carbon as forests at the cool end of the temperature range. This may reflect thermal constraints on tree growth detected through other plot networks and physiological studies. Through common protocols and careful sampling design, the Ausplots Forest Monitoring Network will facilitate the integration of tall eucalypt forests into established global forest monitoring initiatives. In the context of projections of rapidly warming and drying climates in Australia, this plot network will enable detection of links between climate and growth, mortality and carbon dynamics of eucalypt forests.  相似文献   

19.
This data paper reports spectral reflectance and transmittance data of leaves from 21 terrestrial vascular plant species (seven herbaceous, and 14 broadleaf and long-needle coniferous tree species) and of shoots from one short-needle coniferous tree species. The reflectance spectra of branches of one tree species, of the trunks of 12 tree species and ground surface of one deciduous broad-leaf forest are also reported. Optical measurements and leaf samplings were made at five sites on Honshu Island, Japan, which are typical vegetation types in East Asia, i.e., grassland, paddy field, and deciduous broad-leaf or coniferous forests. The collection and measurements were conducted for main species in each site. To include other common vegetation types in East Asia, such as evergreen broad-leaf or coniferous forests, the sample collection and the measurements were conducted at gardens and an experimental forest. Leaves of ten deciduous species were measured at different phenological stages from leaf expansion to senescence since those species shows significant seasonal changes in spectral reflectance and transmittance of leaves. Leaves at different position in a canopy (e.g., sunlit versus shaded leaves) were also measured for eight of 21 species. The spectral reflectance and transmittance from both adaxial and abaxial sides of the all leaves or needles, expect Picea abies needles. The measurements of the leaves were conducted with a spectroradiometer attached via an optical fiber to an integrating sphere. Two types of integrating spheres were used: a model LI-1800-12 (Li-Cor) and an RTS-3ZC integrating sphere (Analytical Spectral Devices). A leaf clip accessory was also used instead of an integrating sphere for measuring the leaves of two species. All data were measured within the 350–2,500-nm spectral range with 1-nm steps between measurements but the data obtained by LI-1800 is unavailable in 1,650–1,740, 1,890–1,950, and 2,050–2,500 nm because of a large amount of noise. These data are used as input parameters in a radiative transfer model designed to estimate the leaf area index from radiation reflected from a canopy surface.  相似文献   

20.
We studied the tree communities in primary forest and three different land use systems (forest gardens, ca. 5-year-old secondary forests, cacao plantations) at 900–1200 m elevation in the environs of Lore Lindu National Park, Central Sulawesi. The primary forests had ca. 150 tree species 10 cm diameter at breast height (dbh) per hectare, which is unusually high for forests at this elevation in southeast Asia. Basal area in the primary forest was 140 m2 ha–1, one of the highest values ever recorded in tropical forests worldwide. Tree species richness declined gradually from primary forest to forest gardens, secondary forests, and cacao plantations. This decline was paralleled by shifts in tree family composition, with Lauraceae, Meliaceae, and Euphorbiaceae being predominant in primary forests, Euphorbiaceae, Rubiaceae and Myristicaeae dominating in the forest gardens and Euphorbiaceae, Urticaceae, and Ulmaceae in the secondary forests. Cacao plantations were composed almost exclusively of cacao trees and two species of legume shade trees. Forest gardens further differed from primary forests by a much lower density of understorey trees, while secondary forests had fewer species of commercial interest. Comparative studies of birds and butterflies demonstrated parallel declines of species richness, showing the importance of trees in structuring tropical forest habitats and in providing resources.  相似文献   

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