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1.
An ecological classification of forest landscape simulation models: tools and strategies for understanding broad-scale forested ecosystems 总被引：5，自引：1，他引：5
Computer models are increasingly being used by forest ecologists and managers to simulate long-term forest landscape change.
We review models of forest landscape change from an ecological rather than methodological perspective. We developed a classification
based on the representation of three ecological criteria: spatial interactions, tree species community dynamics, and ecosystem
processes. Spatial interactions are processes that spread across a landscape and depend upon spatial context and landscape
configuration. Communities of tree species may change over time or can be defined a priori. Ecosystem process representation
may range from no representation to a highly mechanistic, detailed representation. Our classification highlights the implicit
assumptions of each model group and helps define the problem set for which each model group is most appropriate. We also provide
a brief history of forest landscape simulation models, summarize the current trends in methods, and consider how forest landscape
models may evolve and continue to contribute to forest ecology and management. Our classification and review can provide novice
modelers with the ecological context for understanding or choosing an appropriate model for their specific hypotheses. In
addition, our review clarifies the challenges and opportunities that confront practicing model users and model developers. 相似文献
2.
Robert Michael Scheller 《Landscape Ecology》2018,33(9):1481-1488
Forest landscape modeling encompasses many core principles of landscape ecology: spatial resolution and extent, spatially explicit local and regional context, disturbance dynamics, integration of human activity, and explicit links to management and policy. Models of forest change inform land managers about strategies to adapt to the effects of an altered or changing environment across large, forested landscapes. Despite past successes, major challenges remain for landscape ecologists representing the dynamics of complex systems with a computer model, particularly given climate change. Here, I review major modeling challenges unique to climate change and suggest paths forward as climate change increasingly becomes a focus of landscape modeling efforts. 相似文献
3.
Douglas J. Bruggeman Thorsten Wiegand Jeffrey R. Walters Fernando González Taboada 《Landscape Ecology》2014,29(4):639-653
Dispersal is a critical biological process that contributes to the persistence of species in complex and dynamic landscapes. However, little is known about the ability of different types of data to reveal how species interact with landscape patterns during dispersal. Further, application of process-based, landscape-scale models able to capture the influence of land use and climate change are limited by this lack of dispersal knowledge. Here we highlight a method for building such models when dispersal parameters are unknown, but information on the mating system and survival are available. We applied a common statistical framework, rooted in information theory, to contrast the ability of abundance, movement, and genetic data to estimate dispersal parameters for endangered Red-cockaded woodpecker (RCW), using an individual-based, spatially-explicit population model. Dispersal was modeled as a multifaceted process in which foray distance, long-distance dispersal, competition for mates, and landscape permeability were treated as uncertain. We found that movement data are three-times more powerful than abundance data collected at the same spatial and temporal scales. However, habitat occupancy data collected over much a shorter time scale but at regional spatial scales were very effective for estimating dispersal. We also found that one-year of abundance data provided a similar reduction in uncertainty as genetic differences among breeding groups estimated using a 24-year pedigree. Substituting population genetic data for movement and abundance data often led to the same parameter values, but not always. Our study highlights important differences in the information content of data commonly collected in the field. 相似文献
4.
Process-based forest landscape models are valuable tools for testing basic ecological theory and for projecting how forest
landscapes may respond to climate change and other environmental shifts. However, the ability of these models to accurately
predict environmentally-induced shifts in species distributions as well as changes in forest composition and structure is
often contingent on the phenomenological representation of individual-level processes accurately scaling-up to landscape-level
community dynamics. We use a spatially explicit landscape forest model (LandClim) to examine how three alternative formulations
of individual tree growth (logistic, Gompertz, and von Bertalanffy) influence model results. Interactions between growth models
and landscape characteristics (landscape heterogeneity and disturbance intensity) were tested to determine in what type of
landscape simulation results were most sensitive to growth model structure. We found that simulation results were robust to
growth function formulation when the results were assessed at a large spatial extent (landscape) and when coarse response
variables, such as total forest biomass, were examined. However, results diverged when more detailed response variables, such
as species composition within elevation bands, were considered. These differences were particularly prevalent in regions that
included environmental transition zones where forest composition is strongly driven by growth-dependent competition. We found
that neither landscape heterogeneity nor the intensity of landscape disturbances accentuated simulation sensitivity to growth
model formulation. Our results indicate that at the landscape extent, simulation results are robust, but the reliability of
model results at a finer resolution depends critically on accurate tree growth functions. 相似文献
5.
Matthew J. Duveneck Jonathan R. Thompson Eric J. Gustafson Yu Liang Arjan M. G. de Bruijn 《Landscape Ecology》2017,32(7):1385-1397
Context
Forests throughout eastern North America continue to recover from broad-scale intensive land use that peaked in the nineteenth century. These forests provide essential goods and services at local to global scales. It is uncertain how recovery dynamics, the processes by which forests respond to past forest land use, will continue to influence future forest conditions. Climate change compounds this uncertainty.Objectives
We explored how continued forest recovery dynamics affect forest biomass and species composition and how climate change may alter this trajectory.Methods
Using a spatially explicit landscape simulation model incorporating an ecophysiological model, we simulated forest processes in New England from 2010 to 2110. We compared forest biomass and composition from simulations that used a continuation of the current climate to those from four separate global circulation models forced by a high emission scenario (RCP 8.5).Results
Simulated forest change in New England was driven by continued recovery dynamics; without the influence of climate change forests accumulated 34 % more biomass and succeed to more shade tolerant species; Climate change resulted in 82 % more biomass but just nominal shifts in community composition. Most tree species increased AGB under climate change.Conclusions
Continued recovery dynamics will have larger impacts than climate change on forest composition in New England. The large increases in biomass simulated under all climate scenarios suggest that climate regulation provided by the eastern forest carbon sink has potential to continue for at least a century.6.
Stephen R. Shifley Hong S. He Heike Lischke Wen J. Wang Wenchi Jin Eric J. Gustafson Jonathan R. Thompson Frank R. ThompsonIII William D. Dijak Jian Yang 《Landscape Ecology》2017,32(7):1307-1325
Context
Quantitative models of forest dynamics have followed a progression toward methods with increased detail, complexity, and spatial extent.Objectives
We highlight milestones in the development of forest dynamics models and identify future research and application opportunities.Methods
We reviewed milestones in the evolution of forest dynamics models from the 1930s to the present with emphasis on forest growth and yield models and forest landscape models We combined past trends with emerging issues to identify future needs.Results
Historically, capacity to model forest dynamics at tree, stand, and landscape scales was constrained by available data for model calibration and validation; computing capacity; model applicability to real-world problems; and ability to integrate biological, social, and economic drivers of change. As computing and data resources improved, a new class of spatially explicit forest landscape models emerged.Conclusions
We are at a point of great opportunity in development and application of forest dynamics models. Past limitations in computing capacity and in data suitable for model calibration or evaluation are becoming less restrictive. Forest landscape models, in particular, are ready to transition to a central role supporting forest management, planning, and policy decisions.Recommendations
Transitioning forest landscape models to a central role in applied decision making will require greater attention to evaluating performance; building application support staffs; expanding the included drivers of change, and incorporating metrics for social and economic inputs and outputs.7.
Controlling spatial structure of forested landscapes: a case study towards landscape management 总被引：6，自引：0，他引：6
Emin Z. Baskent 《Landscape Ecology》1999,14(1):83-97
8.
Forest fragmentation, climate change and understory fire regimes on the Amazonian landscapes of the Xingu headwaters 总被引：1，自引：1，他引：0
Britaldo Soares-Filho Rafaella Silvestrini Daniel Nepstad Paulo Brando Hermann Rodrigues Ane Alencar Michael Coe Charton Locks Letícia Lima Letícia Hissa Claudia Stickler 《Landscape Ecology》2012,27(4):585-598
Understory fire modeling is a key tool to investigate the cornerstone concept of landscape ecology, i.e. how ecological processes relate to landscape structure and dynamics. Within this context, we developed FISC??a model that simulates fire ignition and spread and its effects on the forest carbon balance. FISC is dynamically coupled to a land-use change model to simulate fire regimes on the Amazonian landscapes of the Xingu Headwaters under deforestation, climate change, and land-use management scenarios. FISC incorporates a stochastic cellular automata approach to simulate fire spread across agricultural and forested lands. CARLUC, nested in FISC, simulates fuel dynamics, forest regrowth, and carbon emissions. Simulations of fire regimes under modeled scenarios revealed that the major current and future driver of understory fires is forest fragmentation rather than climate change. Fire intensity proved closely related to the landscape structure of the remaining forest. While climate change may increase the percentage of forest burned outside protected areas by 30% over the next four decades, deforestation alone may double it. Nevertheless, a scenario of forest recovery and better land-use management would abate fire intensity by 18% even in the face of climate change. Over this time period, the total carbon balance of the Xingu??s forests varies from an average net sink of 1.6?ton?ha?1?year?1 in the absence of climate change, fire and deforestation to a source of ?0.1?ton?ha?1?year?1 in a scenario that incorporates these three processes. 相似文献
9.
Contemporary landscape ecology continues to explore the causes and consequences of landscape heterogeneity across a range of scales, and demands for the scientific underpinnings of landscape planning and management still remains high. The spatial distribution of resources can be a key element in determining habitat quality, and that in turn is directly related to the level of heterogeneity in the system. In this sense, forest habitat mosaics may be more affected by lack of heterogeneity than by structural fragmentation. Nonetheless, increasing spatial heterogeneity at a given spatial scale can also decrease habitat patch size, with potential negative consequences for specialist species. Such dual effect may lead to hump-backed shape relationships between species diversity and heterogeneity, leading to three related assumptions: (i) at low levels of heterogeneity, an increase in heterogeneity favours local and regional species richness, (ii) there is an optimum heterogeneity level at which a maximum number of species is reached, (iii) further increase in spatial heterogeneity has a negative effect on local and regional species richness, due to increasing adverse effects of habitat fragmentation. In this study, we investigated the existence of a hump-shaped relationship between local plant species richness and increasing forest landscape heterogeneity on a complex mosaic in the French Alps. Forest landscape heterogeneity was quantified with five independent criteria. We found significant quadratic relationships between local forest species richness and two heterogeneity criteria indicators, showing a slight decrease of forest species richness at very high heterogeneity levels. Species richness–landscape heterogeneity relationships varied according to the heterogeneity metrics involved and the type of species richness considered. Our results support the assumption that intermediate levels of heterogeneity may support more species than very high levels of heterogeneity, although we were not able to conclude for a systematic negative effect of very high levels of heterogeneity on local plant species richness. 相似文献
10.
Nathan H. Schumaker Allen Brookes Jeffrey R. Dunk Brian Woodbridge Julie A. Heinrichs Joshua J. Lawler Carlos Carroll David LaPlante 《Landscape Ecology》2014,29(4):579-592
Source-sink dynamics are an emergent property of complex species–landscape interactions. A better understanding of how human activities affect source-sink dynamics has the potential to inform and improve the management of species of conservation concern. Here we use a study of the northern spotted owl (Strix occidentalis caurina) to introduce new methods for quantifying source-sink dynamics that simultaneously describe the population-wide consequences of changes to landscape connectivity. Our spotted owl model is mechanistic, spatially-explicit, individual-based, and incorporates competition with barred owls (Strix varia). Our observations of spotted owl source-sink dynamics could not have been inferred solely from habitat quality, and were sensitive to landscape connectivity and the spatial sampling schemes employed by the model. We conclude that a clear understanding of source-sink dynamics can best be obtained from sampling simultaneously at multiple spatial scales. Our methodology is general, can be readily adapted to other systems, and will work with population models ranging from simple and low-parameter to complex and data-intensive. 相似文献
11.
Jaymi J. LeBrun Jeffrey E. Schneiderman Frank R. ThompsonIII William D. Dijak Jacob S. Fraser Hong S. He Joshua J. Millspaugh 《Landscape Ecology》2017,32(7):1433-1446
Context
Global temperatures are projected to increase and affect forests and wildlife populations. Forest management can potentially mitigate climate-induced changes through promoting carbon sequestration, forest resilience, and facilitated change.Objectives
We modeled direct and indirect effects of climate change on avian abundance through changes in forest landscapes and assessed impacts on bird abundances of forest management strategies designed to mitigate climate change effects.Methods
We coupled a Bayesian hierarchical model with a spatially explicit landscape simulation model (LANDIS PRO) to predict avian relative abundance. We considered multiple climate scenarios and forest management scenarios focused on carbon sequestration, forest resilience, and facilitated change over 100 years.Results
Management had a greater impact on avian abundance (almost 50% change under some scenarios) than climate (<3% change) and only early successional and coniferous forest showed significant change in percent cover across time. The northern bobwhite was the only species that changed in abundance due to climate-induced changes in vegetation. Northern bobwhite, prairie warbler, and blue-winged warbler generally increased in response to warming temperatures but prairie warbler exhibited a non-linear response and began to decline as summer maximum temperatures exceeded 36 °C at the end of the century.Conclusion
Linking empirical models with process-based landscape change models can be an effective way to predict climate change and management impacts on wildlife, but time frames greater than 100 years may be required to see climate related effects. We suggest that future research carefully consider species-specific effects and interactions between management and climate.12.
Thomas A. Spies Thomas W. Giesen Frederick J. Swanson Jerry F. Franklin Denise Lach K. Norman Johnson 《Landscape Ecology》2010,25(8):1185-1199
Conserving biological diversity in a changing climate poses major challenges for land managers and society. Effective adaptive
strategies for dealing with climate change require a socio-ecological systems perspective. We highlight some of the projected
ecological responses to climate change in the Pacific Northwest, U.S.A and identify possible adaptive actions that federal
forest managers could take. The forest landscape, ownership patterns and recent shift toward ecologically based forest management
provide a good starting place for conserving biological diversity under climate change. Nevertheless, undesirable changes
in species and ecosystems will occur and a number of adaptive actions could be undertaken to lessen the effects of climate
change on forest ecosystems. These include: manipulation of stand and landscape structure to increase ecological resistance
and resilience; movement of species and genotypes; and engaging in regional, multi-ownership planning to make adaptive actions
more effective. Although the language and goals of environmental laws and policies were developed under the assumption of
stable climate and disturbance regimes, they appear to be flexible enough to accommodate many adaptive actions. It is less
certain, however, if sufficient social license and economic capacity exist to undertake these actions. Given the history of
contentious and litigious debate about federal forest management in this region, it is likely that some of these actions will
be seen as double-edge swords, spurring social resistance, especially where actions involve cutting trees. Given uncertainties
and complexity, collaborative efforts that promote learning (e.g. adaptive management groups) must be rejuvenated and expanded. 相似文献
13.
Context
Converting monocultures to mixed-species stands is thought to be a promising approach to increase forest productivity and resilience, while additionally providing other ecosystem goods and services (EGS). However, the importance of tree species composition and structure remains unclear, particularly beyond the stand scale due to the difficulty of conducting comprehensive, long-term experiments.Objectives
To compare the ability of different tree species mixtures to provide various EGS at the landscape scale.Methods
We used a dynamic forest landscape model to simulate all possible combinations of dominant tree species for two landscapes; a high-elevation alpine region (Dischma valley, Switzerland) and a lowland valley (Mt. Feldberg, Germany). We evaluated multiple EGS, including protection from gravitational hazards, aboveground biomass, and habitat quality, and examined trade-offs and synergies between them.Results
Mixed-species forests were usually better in providing multiple EGS, although monocultures were often best for single EGS. The simulation results also demonstrated how changing environmental conditions along an elevational gradient had a strong impact on the structure of different species combinations and therefore on the provisioning of EGS.Conclusion
Tree species diversity alone is not a good predictor of multifunctionality. Mixtures should be selected based on local environmental conditions, complementary functional traits, and the ability to provide the EGS of interest. Although our work focused on current climatic conditions, we discuss how the modelling framework could be employed to consider the impacts of climate change and disturbances to improve our understanding of how mixed-species stands could be used to cope with these challenges.14.
William D. Dijak Brice B. Hanberry Jacob S. Fraser Hong S. He Wen J. Wang Frank R. ThompsonIII 《Landscape Ecology》2017,32(7):1365-1384
Context
Global climate change impacts forest growth and methods of modeling those impacts at the landscape scale are needed to forecast future forest species composition change and abundance. Changes in forest landscapes will affect ecosystem processes and services such as succession and disturbance, wildlife habitat, and production of forest products at regional, landscape and global scales.Objectives
LINKAGES 2.2 was revised to create LINKAGES 3.0 and used it to evaluate tree species growth potential and total biomass production under alternative climate scenarios. This information is needed to understand species potential under future climate and to parameterize forest landscape models (FLMs) used to evaluate forest succession under climate change.Methods
We simulated total tree biomass and responses of individual tree species in each of the 74 ecological subsections across the central hardwood region of the United States under current climate and projected climate at the end of the century from two general circulation models and two representative greenhouse gas concentration pathways.Results
Forest composition and abundance varied by ecological subsection with more dramatic changes occurring with greater changes in temperature and precipitation and on soils with lower water holding capacity. Biomass production across the region followed patterns of soil quality.Conclusions
Linkages 3.0 predicted realistic responses to soil and climate gradients and its application was a useful approach for considering growth potential and maximum growing space under future climates. We suggest Linkages 3.0 can also can used to inform parameter estimates in FLMs such as species establishment and maximum growing space.15.
Responses of Chilean forest birds to anthropogenic habitat fragmentation across spatial scales 总被引：1，自引：1，他引：0
Although it is recognized that anthropogenic forest fragmentation affects habitat use by organisms across multiple spatial
scales, there is uncertainty about these effects. We used a hierarchical sampling design spanning three spatial scales of
habitat variability (landscape > patch > within-patch) and generalized mixed-effect models to assess the scale-dependent responses
of bird species to fragmentation in temperate forests of southern Chile. The abundances of nine of 20 bird species were affected
by interactions across spatial scales. These interactions resulted in a limited effect of within-patch habitat structure on
the abundance of birds in landscapes with low forest cover, suggesting that suitable local habitats, such as sites with dense
understory cover or large trees, are underutilized or remain unused in highly fragmented landscapes. Habitat specialists and
cavity-nesters, such as tree-trunk foragers and tapaculos, were most likely to exhibit interactions across spatial scales.
Because providing additional sites with dense understory vegetation or large habitat trees does not compensate the negative
effect of the loss of forest area on bird species, conservation strategies should ensure the retention of native forest patches
in the mixed-use landscapes. 相似文献
16.
Melissa S. Lucash Robert M. Scheller Eric J. Gustafson Brian R. Sturtevant 《Landscape Ecology》2017,32(5):953-969
Context
Resilience, the ability to recover from disturbance, has risen to the forefront of scientific policy, but is difficult to quantify, particularly in large, forested landscapes subject to disturbances, management, and climate change.Objectives
Our objective was to determine which spatial drivers will control landscape resilience over the next century, given a range of plausible climate projections across north-central Minnesota.Methods
Using a simulation modelling approach, we simulated wind disturbance in a 4.3 million ha forested landscape in north-central Minnesota for 100 years under historic climate and five climate change scenarios, combined with four management scenarios: business as usual (BAU), maximizing economic returns (‘EcoGoods’), maximizing carbon storage (‘EcoServices’), and climate change adaption (‘CCAdapt’). To estimate resilience, we examined sites where simulated windstorms removed >70% of the biomass and measured the difference in biomass and species composition after 50 years.Results
Climate change lowered resilience, though there was wide variation among climate change scenarios. Resilience was explained more by spatial variation in soils than climate. We found that BAU, EcoGoods and EcoServices harvest scenarios were very similar; CCAdapt was the only scenario that demonstrated consistently higher resilience under climate change. Although we expected spatial patterns of resilience to follow ownership patterns, it was contingent upon whether lands were actively managed.Conclusions
Our results demonstrate that resilience may be lower under climate change and that the effects of climate change could overwhelm current management practices. Only a substantial shift in simulated forest practices was successful in promoting resilience.17.
Amy Pocewicz Max Nielsen-Pincus Caren S. Goldberg Melanie H. Johnson Penelope Morgan Jo Ellen Force Lisette P. Waits Lee Vierling 《Landscape Ecology》2008,23(2):195-210
To make informed planning decisions, community leaders, elected officials, scientists, and natural resource managers must
be able to evaluate potential effects of policies on land use change. Many land use change models use remotely-sensed images
to make predictions based on historical trends. One alternative is a survey-based approach in which landowners’ stated intentions
are modeled. The objectives of our research were to: (1) develop a survey-based landowner decision model (SBM) to simulate
future land use changes, (2) compare projections from the SBM with those from a trend-based model (TBM), and (3) demonstrate
how two alternative policy scenarios can be incorporated into the SBM and compared. We modeled relationships between land
management decisions, collected from a mail survey of private landowners, and the landscape, using remotely-sensed imagery
and ownership parcel data. We found that SBM projections were within the range of TBM projections and that the SBM was less
affected by errors in image classification. Our analysis of alternative policies demonstrates the importance of understanding
potential effects of targeted land use policies. While policies oriented toward increasing enrollment in the Conservation
Reserve Program (CRP) resulted in a large (11–13%) increase in CRP lands, policies targeting increased forest thinning on
private non-industrial lands increased low-density forest projections by only 1%. The SBM approach is particularly appropriate
for landscapes including many landowners, because it reflects the decision-making of the landowners whose individual actions
will result in collective landscape change. 相似文献
18.
Responses of species to landscape modifications are generally documented through their distribution at a given time along
an intensity gradient of land transformation. By focusing on patterns, we are limited to infer ecological processes occurring
within a system and its response to environmental disturbances which can further change over time. Using diachronic datasets
at the scale of France, we analyzed the spatial responses of the black-billed magpie, which has recently colonized cities,
to landscape urbanization. This study applied recently developed statistical approaches incorporating detection uncertainty
of the magpie, based on the capture-recapture statistical framework. We tested whether, and how, extinction and colonization
mechanisms influenced variations of magpie occupancy from 2001 to 2005. In addition, we assessed the importance of the recent
urbanization of the French countryside in determining population dynamics. Overall, our analysis proved that the proportion
of urban areas and recent urbanization in France led to an increase in the probability of magpie occupancy. Unexpectedly,
the species is concomitantly disappearing from the countryside, leading to a rapid change in the distribution of the species.
This study stressed the importance of incorporating detection uncertainty in inference process about spatial dynamics. Overall,
we show how useful it is to account for the dynamic evolution of the landscape in ecological studies. 相似文献
19.
Dead wood is a critical resource for biodiversity in boreal forests. We analysed the persistence of five model species inhabiting
dead wood. By parameterising a metapopulation model (the incidence function model), the model species were all assigned characteristics
that makes it likely that they have disappeared from some (20%) forest landscapes with a long history of forest management.
In the metapopulation model, a forest stand (5 ha) was regarded as a habitat patch. The amount of habitat in each patch was
obtained from models of dead wood dynamics of Norway spruce in central Sweden. Dead wood generated by altered management over
the entire landscape was found to be less efficient in reducing extinction risks in comparison to the same amount of dead
wood generated by protecting reserves. Because generation of dead wood by altered management is often less expensive than
setting aside reserves, it is difficult to determine which conservation measure is most cost-efficient. In a landscape subjected
to forestry for the first time, it was better to preserve a few large reserves than many small ones. However, in a managed,
highly fragmented forest landscape it was better to set aside many small reserves. The reason for this was that small plots
with high habitat quality could be selected, while large reserves originally contained habitats both of high and low quality,
and the rate of habitat quality increase was low. A strategy for biodiversity conservation in a managed forest landscape should
include information about the history of the landscape, the current amount and spatial distribution of forest habitats, and
the potential for rapid restoration of forest habitats, both on managed and unmanaged forest land. 相似文献
20.
Forest fragmentation and regrowth in an institutional mosaic of community, government and private ownership in Nepal 总被引：1，自引：0，他引：1
Harini Nagendra Sajid Pareeth Bhawna Sharma Charles M. Schweik Keshav R. Adhikari 《Landscape Ecology》2008,23(1):41-54
This study analyzes forest change in an area of Nepal that signifies a delicate balance between sustaining the needs and livelihood
of a sizable human population dependent on forest products, and an effort to protect important wildlife and other natural
resources. The study area, a portion of the Chitwan valley district of Nepal, represents what may be becoming a common institutional
mosaic in many countries of the world who have a population reliant on forest products for their livelihood: (1) a national
park; (2) a designated park buffer involving participatory forest management programs; (3) scattered patches of designated
community forest; and (4) large areas of adjacent landscape made up of mostly private landholdings under agricultural practices.
Utilizing Landsat images from 1989 and 2000, we analyze land cover change in each of these management zones using landscape
ecology metrics and quantifying proportional distributions of land cover categories. Our results show significant differences
in terms of land cover dynamics and landscape spatial pattern between these land ownership classes. These findings indicate
that community-based institutions (participatory management programs in the park buffer and the designated community forests)
are capable of halting or even reversing trends in deforestation and forest fragmentation. 相似文献