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1.
In November 2004 a catastrophic windstorm destroyed a large part of the spruce forest in the Tatra National Park (Slovakia). The majority of the windthrown area was cleared; only a small part was left uncleared, thereby allowing regeneration by natural succession. The aim of the present study was to assess the impact of the different forestry practices on soil Oribatida. Three different stands were selected for the study, where sampling took place in June and October 2006: control forest stands (REF), windthrown stands left for natural development (NEX) and clear-cut windthrown stands (EXT). The mean abundance of Oribatida recorded in REF and NEX stands was significantly higher than in EXT stands. Kruskal-Wallis test of mean abundance of adults as well as juveniles confirmed significant influence of treatment and date. The highest abundance of adults was found in control forest stands (REF). Post hoc multiple comparison proved significantly lower abundance of adults in clear-cut stands (EXT) compared with REF. The mean abundance of adults and juveniles was several times higher in stands left for natural development (NEX) than in EXT stands. The highest species richness was observed in REF, followed by NEX and EXT stands. Ordination method showed differences in species composition between studied treatments. Furthermore, a much lower abundance of Hermannia gibba, a dweller of leaf litter and upper soil layers, was recorded in cleared stands compared to the other stands. Indeed, windthrown stands had an obvious lower species richness than control stands. The ordination method used demonstrated a significant influence of both treatment and sampling date on the abundance and species richness of Oribatida. The present study showed that clear-cutting of wind-damaged spruce forest markedly decreases the abundance of soil Oribatida compared with windthrown forest stands left to natural succession.  相似文献   

2.
A study on the microarthropod community with special reference to species diversity of Oribatid and Collembola communities (Microarthropoda: Oribatei and Collembola) in Tam Dao National Park of Vietnam, a subtropical evergreen broad leaf alpine forest, was undertaken with the aim to explain how they are related to forest decline, and whether they can be used as bioindicators of forest plant succession. The results have shown that microarthropod community structures, particularly species diversity of oribatid and collembolan communities, are related to forest decline. Therefore they can be used as bioindicators of forest plant succession. In Tam Dao National Park, there was an inverse relation between species diversity of the oribatid and collembola communities. The species diversity of the oribatid community gradually decreased with forest decline whereas the species diversity of the collembola community gradually increased.  相似文献   

3.
Chauvat M  Zaitsev AS  Wolters V 《Oecologia》2003,137(2):269-276
Dynamic approaches to forest ecosystems are surprisingly rare. Here we report about successional changes in collembolan community structure and microbial performances during forest rotation. The study was carried out in a chronosequence of four spruce forest stands (5-, 25-, 45-, and 95 years old; Tharandter forest, Germany). CO2 release significantly increased after clear-cutting and the amount of C stored in the organic layer subsequently declined. The early phase of forest rotation was characterized by a very active decomposer microflora, stimulation of both fungi and bacteria as well as by a high abundance of surface-oriented Collembola. In addition, collembolan species turnover was accelerated. While the biomass of fungi further increased at intermediate stages of forest rotation, the metabolic activity of the microflora was low, the functional diversity of bacteria declined and the collembolan community became impoverished. Euedaphic species dominated during this stage of forest development. These changes can be explained by both reduction in microhabitat diversity and depletion of food sources associated with an accumulation of recalcitrant soil organic matter. Results of the General Regression Model procedure indicate a shift from specific associations between collembolan functional groups and microbiota at the early stage of forest rotation to a more diffuse pattern at intermediate stages. Though the hypothesis that Collembola are relatively responsive to changes in environmental conditions is confirmed, consistently high community similarity suggests a remarkable persistence of some components of microarthropod assemblages. Our study provides evidence for substantial ecosystem-level implications of changes in the soil food web during forest rotation. Moreover, correlations between bacterial parameters and Collembola point to the overarching impact of differences in the composition of the microbial community on microarthropods.  相似文献   

4.
To assess the effect of management of a park on soil arthropods, communities of Oribatida and Collembola were analyzed at 11 sites of different vegetation in Tsurumi Park, an urban park of Osaka City. The type of canopy layer and soil density strongly affected the community parameters, such as species diversity. Ordination revealed that soil density, contents of organic matter, and shrub layer were important for variety in the oribatid community; the shrub layer was important for the collembolan community. Species richness of both arthropod groups was highest in a mixed forest and lowest on bare land, while the abundance of Collembola was highest on a lawn site. Areas of a common vegetation type had a similar oribatid community;Trichogalumma nipponica dominated in deciduous forests,Eohypochthonius crassisetiger in mixed forests and one of coniferous forests. On the other hand, collembolan communities did not correspond with the vegetation.Sminthurinus sp. was collected from every site, and the most abundant species wasCryptopygus thermophilus that exhibited an outbreak on lawn sites. A significant correlation existed between species diversities but not between abundances of Oribatida and Collembola.  相似文献   

5.
A soil arthropod community was studied in a dry evergreen forest over a 3-year period from May 1998 to April 2001. Population abundance, species composition, and community structure were investigated over the 3-year study period. The soil arthropods consisted of Acari (75.38%), Collembola (16.11%), and others (8.51%), and their abundances showed a clear difference between the rainy and dry seasons. Population abundance of Collembola and Acari were low during drought conditions. The humidity was the most important factor determining distribution, abundance, and survival of soil Collembola in this tropical forest. High predation and low accumulation of organic matter caused low population abundance of Collembola in the tropical habitat. The collembolan community was dominated by a few dominant species over the study period. The pattern of seasonal changes in numbers of Collembola was similar over the 3-year study period. The species composition of the collembolan community was constant and persistent throughout a 3-year study period. Thus, the collembolan community showed constancy in its species composition with seasonal variability over the 3-year study period.  相似文献   

6.
Abstract The collembolan faunas of 30 bauxite mines rehabilitated by a range of different methods between 1966 and 1977, and three forest plots were surveyed in the spring and summer of 1978–79 with the aim of studying the restoration of decomposer activity in degraded areas. The rehabilitation methods included seeding and planting with a variety of native or exotic plant species. Physical and botanical parameters of the plots were also measured. Sixty species of Collembola were collected from the rehabilitated areas; nine of the 28 species found in the forest plots were not present on the mined sites. Principal components analysis suggested that the species richness of the collembolan community in rehabilitated areas is positively correlated with plot age. A parametric correlation analysis using a number of collembolan community characteristics revealed that, among other factors, the development of a species rich collembolan fauna is positively correlated with plant species richness and diversity, and also with percentage plant cover. These results provide directions for improving rehabilitation practices.  相似文献   

7.
We investigated which of the following environmental factors: the number of years since the windthrow of the tree (the age of dead wood), the phytocenosis (the type of forest community), altitude, exposure, wood hardness and the spatial scale of forest disturbances (small gaps with a few fallen spruces vs large-area windthrows) contributed to the diversity and abundance of lichens inhabiting the exposed wood of windthrown spruce trees in Polish Western Carpathian forests. Both Shannon H index and sum of coverage coefficients rose with increasing age of the wood, levelling off after 11–14 y (diversity) and 14–17 y (abundance). This factor appeared to be the most important for this group of lichens, but the significant positive impact of large-area windthrows on the lichen abundance was also demonstrated by using a GLM model. The age of the wood we precisely determined on the basis of data on Norway spruce mortality collected annually in permanent plots of the Gorce National Park since 2000. Using the Shore durometer we linked the course of the wood-inhabiting lichen succession with wood decay more precisely than before. The largest number of species was associated with medium hard wood, i.e., 51 < x ≤ 80 on the Shore scale. Based on the NMDS analysis, we distinguished four age groups of logs, differing in lichen abundance and defined by the dominance of distinctive species. A large number of usually corticolous lichen species used the wood of windthrown spruce logs as an optional habitat to survive large-scale, post-hurricane forest disturbances.  相似文献   

8.
Objectives of this study are to summarize the current state of knowledge of the diversity and distribution of Collembola in Brazil; to identify areas of most importance, interest, and need of additional research; and to enable development of experimental hypotheses for future research on Collembola in this region. The total number of collembolan species currently known from Brazil is 199, distributed among 19 families and 80 genera. The greatest numbers of species have been recorded from the states of Rio de Janeiro and Amazonas (with 69 and 56 species, respectively). Few or no species are known from most Brazilian states. Most of the species for which specific Brazilian environmental habitat information is available (93, 66%) are known only from forest environments. Most of the species (127, 64%) are known only from Brazil (most likely being endemic); 33 species (17%) are known only from Brazil and other neotropical areas; and 39 species (20%) have a distribution beyond the neotropical region. Results of this study indicate that much remains to be learned about the Brazilian collembolan fauna. This is especially true for areas of the northeastern, central-western, and southern regions. Studies to determine the species composition of collembolan communities in specific environments in Brazil are needed. The great diversity of Collembola species in Brazil is largely unknown and there are many opportunities for additional research on these environmentally important organisms in this area. Such additional research on the Collembola in Brazil is also essential for a better understanding of the neotropical (and world) collembolan fauna.  相似文献   

9.
A survey of the patterns of wood decaying fungi as to occurrence of sporocarps on naturally fallen logs of Norway spruce ( Picea abies ) was undertaken in two nearby forest stands with different histories of management. One stand was an old-growth forest with few signs of logging, and the other stand was selectively logged 60–80 years ago. Altogether 118 species were found. Forest management had a negative impact on the species diversity. Newly fallen and weakly decayed logs in a natural forest had a higher species richness, more red-listed species, as well as more indicator species compared to similar logs in a managed forest. The importance of dead wood for species diversity of wood inhabiting fungi was clearly demonstrated. Presence of logs in later stages of decomposition increased the total species number in a natural forest stand with 42 (63 %), compared to a survey of only newly fallen and weakly decayed logs. Presence of logs in later stages of decomposition also increased the diversity of the species pool colonising newly fallen and weakly decayed logs. The highest number of fruiting species was found on intermediately decayed logs and on logs lying in contact with the ground. The fungal gradient as revealed in a DCA ordination was primarily related to decay. A successional pathway based on the primary decayer Fomitopsis pinicola was not detected.  相似文献   

10.
The collembolan fauna of the Pinega State Reserve (Arkhangelsk Province) was examined. The study area is highly specific due to its karst topography. In all, 126 Collembola species were recorded in the reserve, a significant fraction of their diversity being restricted to karst habitats. Several species that had never been recorded in plain forest biotopes were of special interest. Such forms with distribution ranges mainly limited to the tundra zone comprised about 10% of the local fauna. Regarding the longitudinal sizes of the ranges, this group was not homogeneous and included both widespread circumpolar and east-Palaearctic (Siberian) species. Several arctoalpine forms were also recorded. Most of these arctic species were not numerous over the area studied and in general, the collembolan assemblages at the coldest sites of the reserve did not differ significantly from those typical of the forest zone, with the exception of two species, Desoria tshernovi and D. inupikella, which often predominated in the karst communities. The origin and appropriateness of the term relict for the revealed “insular” populations of arctic species are discussed.  相似文献   

11.
The response of species numbers and density of Collembola to manipulation of plant species richness (1, 2, 4, 8, 32 species) and number of plant functional groups (grasses, legumes and non-legume herbs) was studied in an experimental grassland at the Swiss BIODEPTH site (Lupsingen, Switzerland) in October 1997. Plant species richness or number of plant functional groups did not affect total diversity of Collembola, however, the number of Collembola species increased in the presence of legumes and the grass Trisetum flavescens . The abundance of Protaphorura armata increased but that of Hypogastruridae/Neanuridae significantly decreased with increasing number of plant functional groups. Other groups including the herbivorous Symphypleona did not respond to plant species richness and plant functional groups. Possibly, Hypogastruridae/Neanuridae species are weak competitors declining in density if the density of other Collembola groups increase. In general, the effect of the number of plant functional groups on the densities of collembolan taxa was stronger than that of plant species richness. Changes in Collembola density and diversity in part was likely caused by increased soil microbial and fine root biomass in treatments with higher plant functional group diversity. The presence of legumes resulted in an increase in the densities of total Collembola, Symphypleona/Neelipleona and Isotomidae indicating that they benefited from the high litter quality and the increased microbial biomass in the rhizosphere of legumes. The results suggest that microbivorous soil invertebrates are controlled by food quality rather than quantity. Furthermore, they indicate that presence of certain plant species and functional groups may be more important for collembolan community structure than the diversity of plant species and functional groups per se.  相似文献   

12.
Bryophyte and fungal communities were investigated on fallen trees representing seven deciduous tree species in a mixed near natural nemoral forest. Bryophytes were represented by 41 taxa, including several very frequent species. Of the 296 fungal species, most were recorded with very low frequency and the share of high frequent species was much lower than among the bryophytes. Species turnover was bigger in the fungal communities, compared to the bryophyte communities, and related to a higher extent to measured differences in environmental conditions. Tree species diversity was found to be an important factor for fungal species composition, while only small differences in bryophyte species composition were found between the different tree species. On the other hand bryophyte species richness showed distinct relations to tree species and microclimatic variables, a tendency which was not evident for fungal diversity. It is concluded that the two organism groups to some extent differ in their conservation demands. Thus, conservation of wood-inhabiting bryophytes requires prioritising of large, coherent forest stands in which a stable humid microclimate and a reasonable supply of dead wood is secured. Successful conservation of fungi requires that substantial amounts of dead wood are left for natural decay in a variety of natural forest environments representing different tree species, so that heterogeneity in dead wood types is secured.  相似文献   

13.
张铁  于存  戚玉娇 《生态学报》2022,42(7):2774-2783
倒木是森林生态系统的重要组分,其分解调控着土壤的养分循环,同时也影响着土壤微生物群落结构。但目前鲜见关于倒木分解对土壤微生物群落影响方面的报道。选取贵州茂兰喀斯特常绿落叶阔叶混交林中处于轻、中和重度腐烂等级的狭叶润楠(Machilus rehderi)、枫香(Liquidambar formosana)、青冈栎(Cyclobalanopsis glauca)和圆果化香(Platycarya longipes)4种常见树种倒木为研究对象,以距倒木外围的3个不同水平距离(10cm、30cm和50cm)的土壤样品为实验材料,分析倒木树种、腐烂等级和距离对土壤真菌种类及多样性的影响。结果表明:1)喀斯特森林4种树种倒木所影响土壤真菌群落在门级分类上主要为子囊菌门、担子菌门和毛霉门,优势属有Mortierella spp.、Phlebia spp.、Pluteus spp.和Chaetomium spp.等;2)倒木的树种对土壤真菌群落相对丰度的影响有差异,圆果化香倒木下的土壤真菌丰富度Chao1指数显著高于青冈栎;3)随腐烂程度加深,4种树种倒木下的土壤真菌群落多样性呈显著增加趋势;4)土壤真菌群落丰度随着距倒木距离的增大(10-50cm)变化明显,如狭叶润楠影响的Pluteus spp.、Mortierella spp.和Ganoderma spp.,枫香的Chaetomium spp.,圆果化香的Mortierella spp.和青冈栎的Phlebia spp.和Oliveonia spp.等。本研究量化了喀斯特森林倒木所影响的土壤真菌群落组成及分布规律,在一定程度上为倒木分解与土壤微生物群落之间的作用机制的深入探索提供了科学依据。  相似文献   

14.
1. This paper reviews and compares the effects of forest fire and timber harvest on mammalian abundance and diversity, throughout successional time in the boreal forest of North America. 2. Temporal trends in mammal abundance and diversity are generally similar for both harvested and burned stands, with some differences occurring in the initiation stage (0–10 years post disturbance). 3. Small mammals and ungulates are most abundant immediately post disturbance, and decrease as stands age. Lynxes and hares utilize mid-successional stands, but are rare in young and old stands. Bats, arboreal sciurids and mustelids increase in abundance with stand age, and are most abundant in old growth. 4. Substantial gaps in the data exist for carnivores; the response of these species to fire and harvest requires research, as predator–prey interactions can affect mammal community structure in both early and late successional stages. 5. The lack of explicit treatment of in-stand forest structure post disturbance, in the reviewed literature made comparisons difficult. Where forest structure was considered, the presence of downed woody material, live residual trees and standing dead wood were shown to facilitate convergence of mammal communities to a pre-disturbance state for both disturbance types. 6. Mammalian assemblages differed considerably between successional stages, emphasizing the importance of maintaining stands of each successional stage on the landscape when implementing forest management strategies.  相似文献   

15.
小流域治理20年后的千烟洲植物多样性   总被引:15,自引:2,他引:15       下载免费PDF全文
研究了小流域治理20年后千烟洲植物α多样性和β多样性,结果如下:1)优势度:所有人工林乔、灌、草3层均以乔木层优势度最大,且乔木层优势度均大于天然次生林和枫香(Liquidambar formosana)林,而所有天然次生林及枫香林均以乔木层优势度最小。12种类型群落灌木层优势度都较小,均值仅0.17。草本层,白茅(Imperata cylindrica var. major)草丛和檵木(Loropetalum chinense)-疏花雀麦(Bromus remotiflorus)灌丛优势度较大,分别为0.53和0.51。2)多样性:从乔、灌、草3层比较,枫香林、天然马尾松(Pinus massoniana)林以乔木层最大,其它群落以灌木层最大,而所有人工林以乔木层最低。乔木层中枫香林最高(2.61);灌木层和草本层多样性存在相似之处:马尾松 + 湿地松(Pinus elliottii)林最高,除马尾松+山鸡椒(Litsea cubeba)林、板栗(Castanea mollissima)+枫香林外,其它人工林多样性均高于天然次生林和枫香林。3)丰富度:各群落均以灌木层最大;枫香林乔木层和灌木层种类丰富度均很高,但草本层很低;天然次生林乔木层丰富度指数大于人工林。4)均匀度:从灌、草层比较,除檵木-疏花雀麦灌丛和白茅草丛外,其它群落草本层均匀度均大于灌木层。乔木层,板栗+枫香林和马尾松+山鸡椒林均匀度指数很大,大于0.76,其它人工林均匀度小于天然次生林和枫香林。灌木层,除板栗+枫香林外,其它人工林均匀度都大于天然次生林和枫香林。5)β多样性与α多样性相互补充,很好地反映了不同群落类型之间的差异。β多样性将12种类型群落分成3大类,草丛、灌丛、具乔木层的群落,其中草丛与其它类型群落相异性最大。枫香林是位于人工林与天然次生林之间的过渡类型。  相似文献   

16.
人为干扰对闽北森林群落物种多样性的影响   总被引:26,自引:0,他引:26  
本文从群落及其组成结构等方面分析了闽北长期封禁保护的森林(conservedforest,CF)和人为干扰后的退化森林(degradedforest,DF)群落物种多样性,结果认为,DF群落的植物物种丰富度和ShannonWiener指数与CF群落相近或略高,但DF群落植物种类组成和层次结构的物种多样性发生明显变化,群落物种种群基础已改变,稀有种和渐危种缺乏,这正是DF与CF群落物种多样性的本质差异。  相似文献   

17.
This study focuses on the long-term changes of collembolan communities occurring after the conversion of arable land to managed grassland. We analysed collembolan communities at grassland sites of different age that had been gradually converted over a period of 50 yr. Abundance and biomass responded rapidly and very positively to the conversion of arable land to grassland, while species richness was not affected. Collembolan assemblages changed only little during grassland maturation. The impact of land-use change on community structure was more obvious at the functional level because the colonization processes observed in our study mostly relied on hemiedaphic species. Vegetation and soil parameters were good predictors of collembolan community structure during development of managed grassland. The present study demonstrated that past landscape patterns and processes like land-use conversion and subsequent succession had a considerable impact on the present day pattern of species richness and community composition of Collembola within a landscape. Our results strongly differ from those obtained for other invertebrate groups, highlighting on the one hand the very diverse reactions of invertebrates to a common factor, and on the other hand the need to survey more than one taxa in order to draw conclusions on effects of land-use change on faunistic communities.  相似文献   

18.
Fire and herbivores alter vegetation structure and function. Future fire activity is predicted to increase, and quantifying changes in vegetation communities arising from post‐fire herbivory is needed to better manage natural environments. We investigated the effects of post‐fire herbivory on understory plant communities in a coastal eucalypt forest in southeastern Australia. We quantified herbivore activity, understory plant diversity, and dominant plant morphology following a wildfire in 2017 using two sizes of exclosures. Statistical analysis incorporated the effect of exclusion treatments, time since fire, and the effect of a previous prescribed burn. Exclusion treatments altered herbivore activity, but time since fire did not. Herbivory reduced plant species richness, diversity, and evenness and promoted the dominance of the most abundant plants within the understory. Increasing time since fire reduced community diversity and evenness and influenced morphological changes to the dominant understory plant species, increasing size and dead material while decreasing abundance. We found the legacy effects of a previous prescribed burn had no effect on herbivores or vegetation within our study. Foraging by large herbivores resulted in a depauperate vegetation community. As post‐fire herbivory can alter vegetation communities, we postulate that management burning practices may exacerbate herbivore impacts. Future fire management strategies to minimize herbivore‐mediated alterations to understory vegetation could include aggregating management burns into larger fire sizes or linking fire management with herbivore management. Restricting herbivore access following fire (planned or otherwise) can encourage a more diverse and species‐rich understory plant community. Future research should aim to determine how vegetation change from post‐fire herbivory contributes to future fire risk.  相似文献   

19.
Biodiversity conservation of forest ecosystems strongly relies on effective dead wood management. However, the responses of saproxylic communities to variations in dead wood characteristics remains poorly documented, a lack of knowledge that may impede the development of efficient management strategies. We established the relationship between saproxylic beetles—at the species and community levels—and attributes of black spruce and balsam fir in old-growth boreal forests. The relationship was first evaluated for individual snag bole segments, and then for forest stands. A total of 168 bole sections were collected in summer 2006 along a compositional gradient ranging from black spruce-dominated stands to balsam fir-dominated ones, in a boreal forest dominated by >90-year-old stands. A total of 16,804 beetles belonging to 47 species emerged from bole segments, with 21% of the species being found exclusively in black spruce snags and 36% exclusively in balsam fir snags. Black spruce and balsam fir snags thus contributed differently to forest biodiversity by being inhabited by different saproxylic communities. Wood density was an important attribute in the host-use patterns for several species of saproxylic beetles, but no relationship was found between snag availability within stands and abundance of beetles strongly linked to either black spruce or balsam fir. Our study outlines the relative contribution of tree compositional diversity to saproxylic species, while highlighting the contribution of black spruce and balsam fir to animal diversity in old-growth boreal forests.  相似文献   

20.
Questions: How does woody vegetation abundance and diversity differ after natural disturbances causing different levels of mortality? Location: Abies balsamea–Betula papyrifera boreal mixed‐wood stands of southeast Quebec, Canada. Methods: Woody vegetation abundance and diversity were quantified and compared among three disturbance‐caused mortality classes, canopy gap, moderate‐severity disturbances, and catastrophic fire, using redundancy analysis, a constrained linear ordination technique, and diversity indices. Results: Substantial changes in canopy tree species abundance and diversity only occurred after catastrophic fire. Shade‐tolerant, late‐successional conifer species remained dominant after canopy gap and moderate‐severity disturbances, whereas shade‐intolerant, early‐successional colonizers dominated canopy tree regeneration after catastrophic fire. Density and diversity of mid‐tolerant and shade‐intolerant understory tree and shrub species increased as the impact of disturbance increased. Highest species richness estimates were observed after catastrophic fire, with several species establishing exclusively under these conditions. Relative abundance of canopy tree regeneration was most similar after canopy gap and moderate‐severity disturbances. For the sub‐canopy tree and shrub community, relative species abundances were most similar after moderate‐severity disturbances and catastrophic fire. Vegetation responses to moderate‐severity disturbances thus had commonalities with both extremes of the disturbance‐caused mortality gradient, but for different regeneration layers. Conclusions: Current spatio‐temporal parameters of natural disturbances causing varying degrees of mortality promote the development of a complex, multi‐cohort forest condition throughout the landscape. The projected increase in time intervals between catastrophic fires may lead to reduced diversity within the system.  相似文献   

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