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1.
由于人类对土地功能的认识单一，造成乡村地区土地利用不充分，导致土地资源的闲置与浪费。而土地单一功能利用模式转变的关键是探究土地多功能的利用。以北流河流域林地为研究区对象，从气候、土壤、地质、地形、植被要素进行综合分析，对林地土地的生产功能、生态功能、景观功能和材料功能进行空间定量化，运用热点分析和地理探测器评价北流河流域林地多功能性及影响因素；并通过K均值聚类分析划分林地土地多功能利用类型区。结果表明：(1)流域内林地多功能热点区域呈集聚分布，冷点区域呈带状分布在北流河流域的山麓。(2)北流河流域林地多功能空间分异的驱动力主要以植被因素为主，其中郁闭度、蓄积量、碳汇为主导因子，植被盖度对林地土地多功能空间分异的影响较小，应加强北流河流域内的植被保护和严禁过度开发林地；交互作用明显，交互作用均为双因子增强或非线性增强，气候、土壤、植被、地形、地质条件共同制约着北流河流域林地多功能水平。(3)通过伪F统计将北流河流域林地划分为3个主导区和1个提升区，分别为生产功能主导区、生态功能主导区、景观功能主导区以及综合功能提升区，其中生态功能主导区面积最大；并针对主导功能提出相应的利用方向。 相似文献
2.
Howell Christine A. Latta Steven C. Donovan Therese M. Porneluzi Paul A. Parks Geoffrey R. Faaborg John 《Landscape Ecology》2000,15(6):547-562
We examine the influence of both local habitat and landscape variables on avian species abundance at forested study sites situated within fragmented and contiguous landscapes. The study was conducted over a six year period (1991–1996) at 10 study sites equally divided between the heavily forested Missouri Ozarks and forest fragments in central Missouri. We found greater species richness and diversity in the fragments, but there was a higher percentage of Neotropical migrants in the Ozarks. We found significant differences in the mean number of birds detected between the central Missouri fragments and the unfragmented Ozarks for 15 (63%) of 24 focal species. We used stepwise regression to determine which of 12 local vegetation variables and 4 landscape variables (forest cover, core area, edge density, and mean patch size) accounted for the greatest amount of variation in abundance for 24 bird species. Seven species (29%) were most sensitive to local vegetation variables, while 16 species (67%) responded most strongly to one of four landscape variables. Landscape variables are significant predictors of abundance for many bird species; resource managers should consider multiple measures of landscape sensitivity when making bird population management decisions.Order of first two authors decided by coin toss 相似文献
3.
A GIS-based method for the reconstruction of the late eighteenth century forest vegetation in the Prignitz region (NE Germany) 总被引：1，自引：0，他引：1
Our goal was to reconstruct the late eighteenth century forest vegetation of the Prignitz region (NE Germany) at a scale of
1:50,000. We also wanted to relate the historical forest vegetation to the actual and potential natural vegetation. For these
purposes, we selected 15 woody species and transferred relevant data found in historical records from various sources together
with the recent localities of (very) old individuals belonging to these woody species into ArcView GIS. Following multi-step
data processing including the generation of a point density layer using a moving window with kernel estimation and derivation
of vegetation units applying Boolean algebra rules together with information on site conditions, we derived 17 forest communities
corresponding to the potential natural vegetation. We were able to reconstruct the historical forest vegetation for 90% of
the forest area ca. 1780. Only two of the 17 forest communities covered large parts of the forested area. The oak forest with
Agrostis capillaris covered about 44% of the total forest area, and alder forests on fenland made up about 37%. Oak-hornbeam forests with Stellaria holostea comprised slightly less than 6% of the forest area, while all other forest communities comprised less than 1%. The historical
forest vegetation is more similar to the potential forest vegetation and quite different from the actual forest vegetation
because coniferous tree species currently cover approximately two-thirds of the actual forest area. The most beneficial result
of this study is the map of high-resolution historical vegetation units that may serve as the basis for various further studies,
e.g., modelling long-term changes in biodiversity at the landscape scale. 相似文献
4.
Modeling vegetation pattern using digital terrain data 总被引：10，自引：0，他引：10
Using a geographic information system (GIS), digital maps of environmental variables including geology, topography and calculated
clear-sky solar radiation, were weighted and overlaid to predict the distribution of coast live oak (Ouercus agrifolia) forest in a 72 km2 region near Lompoc, California. The predicted distribution of oak forest was overlaid on a map of actual oak forest distribution
produced from remotely sensed data, and residuals were analyzed to distinguish prediction errors due to alteration of the
vegetation cover from those due to defects of the statistical predictive model and due to cartographic errors.
Vegetation pattern in the study area was associated most strongly with geologic substrate. Vegetation pattern was also significantly
associated with slope, exposure and calculated monthlysolar radiation. The proportion of observed oak forest occurring on
predicted oak forest sites was 40% overall, but varied substantially between substrates and also depended strongly on forest
patch size, with a much higher rate of success for larger forest patches. Only 21% of predicted oak forest sites supported
oak forest, and proportions of observed vegetation on predicted oak forest sites varied significantly between substrates.
The non-random patterns of disagreement between maps of predicted and observed forest indicated additional variables that
could be included to improve the predictive model, as well as the possible magnitude of forest loss due to disturbances in
different parts of the landscape. 相似文献
5.
Persistent changes in forest vegetation and seed bank 1,600 years after human occupation 总被引：1，自引：1，他引：0
Jan Plue Martin Hermy Kris Verheyen Patrice Thuillier Robert Saguez Guillaume Decocq 《Landscape Ecology》2008,23(6):673-688
Past land use is an important factor determining vegetation in temperate deciduous forests. Little is known about the long-term
persistence of these impacts on vegetation but especially on the seed bank. This study assessed whether soil characteristics
remain altered 1,600 years after human occupation and if this yielded persistent differences in forest plant communities and
their seed bank in particular. Compiègne forest is located in northern-France and has a history of continuous forest cover
since the end of Roman times. Twenty-four Gallo-Roman and 24 unoccupied sites were sampled and data were analysed using paired
sample tests to investigate whether soil, vegetation and seed bank still differed significantly. The soil was persistently
altered on the Gallo-Roman sites resulting in elevated phosphorus levels and pH (dependent on initial soil conditions) which
translated into increased vegetation and seed bank species richness. Though spatially isolated, Gallo-Roman sites supported
both a homogenized vegetation and seed bank. Vegetation differences were not the only driver behind seed bank differences.
Similarity between vegetation and seed bank was low and the possibility existed that agricultural ruderals were introduced
via the former land use. Ancient human occupation leaves a persistent trace on forest soil, vegetation and seed bank and appears
to do so at least 1,600 years after the former occupation. The geochemical alterations created an entirely different habitat
causing not only vegetation but also the seed bank to have altered and homogenized composition and characteristics. Seed bank
differences likely persisted by the traditional forest management and altered forest environment. 相似文献
6.
为研究外来植物刺萼龙葵对入侵地植被多样性的影响，调查了河北省张家口市宣化区刺萼龙葵的3个不同生境(人工国槐林、河滩、荒坡)的植被，分析物种组成、植被多样性、植被重要值等指标。结果表明，无论哪种生境，刺萼龙葵的多度、频度、盖度与重要值均远远高于其他植物，刺萼龙葵在其入侵区内已经成为优势种；与对照样地相比，刺萼龙葵的生长引起30.00%以上的本土植物在入侵区消失，改变了植被组成和多样性；而原本优势的本土植物，相对多度与盖度也明显降低，其中狗尾草的降幅最大，相对多度和相对盖度分别降低了2.5倍和2.7倍。本研究为全面理解刺萼龙葵的入侵生态风险提供了依据。 相似文献
7.
Landscape history of a calcareous (alvar) grassland in Hanila,western Estonia,during the last three hundred years 总被引：10，自引：4，他引：6
The landscape history of the largest calcareous seminatural alvar site (ca. 700 ha) in Estonia, is described with the help of a historical map from 1705 and aerial photographs from 1951, and recent vegetation mapping from 1994–1996. The seminatural, species rich alvar grasslands originate and are maintained by grazing of domestic animals. Three hundred years ago the area was mainly open grassland with sparse shrubs and some fields. Forty years ago the vegetation pattern was similar, with some smaller forests and forest clear-cut areas present. Now, since grazing has ceased for ca. 40 years, only 30% of the area remains as open grassland and 70% as forest. Identification of clusters of field layer vegetation using the program TABORD resulted in 8 clusters, which agreed with the empirically determined community types. The field layer within the young pine forest (up to 20 year old pines) is similar to the open alvar grassland. In older forests, the field layer has already changed. There were no phytosociological differences found between ancient grasslands and grasslands on former arable fields or forest clear-cut areas. Decrease in species richness, compared to open grassland, was most drastic in forests of age 20–40 years where the canopy was most closed. Forests have spread more extensively in areas with deeper soil. The continuation of traditional management (grazing and tree cutting) in alvar grasslands is urgently needed in order to keep seminatural alvar grasslands open. The possibility to restore open grasslands remains as long as there is a pool of grassland species available, especially in younger forests. 相似文献
8.
Context
Landscape modification is an important driver of biodiversity declines, yet we lack insight into how ongoing landscape change and legacies of historical land use together shape biodiversity.Objectives
We examined how a history of agricultural land use and current forest fragmentation influence the abundance of red-backed salamanders (Plethodon cinereus). We hypothesized that historical agriculture and fragmentation cause changes in habitat quality and landscape structure that limit abundance.Methods
We measured salamander abundance at 95 forested sites in New York, USA, and we determined whether sites were agricultural fields within the last five decades. We used a structural equation model to estimate relationships between historical agriculture and salamander abundance mediated by changes in forest vegetation, microclimate, and landscape structure.Results
Historical agriculture affected salamander abundance by altering forest vegetation at a local scale and forest cover at a landscape scale. Abundance was lowest at post-agricultural sites with low woody vegetation, leaf litter depth, and canopy cover. Post-agricultural sites had limited forest cover in the surrounding landscape historically, and salamander abundance was positively related to historical forest cover, suggesting that connectivity to source populations affects colonization of regenerating forests. Abundance was also negatively related to current forest fragmentation.Conclusions
Historical land use can have legacy effects on animal abundance on par with effects of ongoing landscape change. We showed that associations between animal abundance and historical land use can be driven by altered site conditions and surrounding habitat area, indicating that restoration efforts should consider local site conditions and landscape context.9.
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
10.
Effects of site,landscape features,and fire regime on vegetation patterns in presettlement southern Wisconsin 总被引：2，自引：0，他引：2
Lawrence A. Leitner Christopher P. Dunn Glenn R. Guntenspergen Forest Stearns David M. Sharpe 《Landscape Ecology》1991,5(4):203-217
The presettlement tree cover (1831–33) of 3 townships in a southern Wisconsin landscape was analyzed using original survey records. Four forest types were identified: closed forest, open forest, savanna, and prairie. Comparisons of vegetation types and landscape pattern were made between the east and west sides of the Pecatonica River, which bisects the landscape and could have acted as a natural fire barrier. West of the river, presettlement tree species richness and diversity were lower and trees were smaller in diameter and less dense than to the east. The major vegetation types to the west were prairie (42% of landscape) and savanna (40%), both fire-susceptible types. Prairie was more common on gentle slopes than on other landforms. To the east, the landscape was 70% forested (closed plus open forest). Here, prairie was more frequent on steep dry sites. These vegetation differences, including the contrasting landscape placement of prairie, are attributed to distinct site characteristics and to disturbance (fire) regimes, with the west likely having more frequent fires. In terms of the four vegetation types, the east landscape was more homogeneous, being dominated by closed forest (50%). West of the Pecatonica River, the landscape was more heterogeneous because of the high proportion of both prairie and savanna; however, in terms of flammability of vegetation, the west was essentially homogeneous (82% prairie plus savanna). 相似文献
11.
12.
Context
Urbanization has altered many landscapes around the world and created novel contexts and interactions, such as the rural–urban interface.Objectives
We sought to address how a forest patch’s location in the rural–urban interface influences which avian species choose to occur within the patch. We predicted a negative relationship between forest bird richness and urbanization surrounding the patch, but that it would be ameliorated by the area of tree cover in the patch and matrix, and that total tree-cover area would be more influential on forest bird species richness than area of tree cover in the focal patch alone.Methods
We conducted bird surveys in 44 forest patches over 2 years in Southeast Michigan and evaluated bird presence and richness relative to patch and matrix tree cover and development density.Results
We observed 43 species, comprised of 21 Neotropical migrants, 19 residents, and three short-distance migrants. Focal-patch tree-cover area and the matrix tree-cover area were the predominant contributors to a site’s overall forest-bird species richness at the rural–urban interface, but the addition of percent of over-story vegetation and percentage of deciduous tree cover influenced the ability of the patches to support forest species, especially Neotropical migrants. Development intensity in the matrix was unrelated to species richness and only had an effect in four species models.Conclusions
Although small forest patches remain an important conservation strategy in developed environments, the influence of matrix tree cover suggests that landscape design decisions in surrounding matrix can contribute conservation value at the rural–urban interface.13.
Small mammals in a mosaic of forest remnants and anthropogenic habitats—evaluating matrix quality in an Atlantic forest landscape 总被引：1，自引：0，他引：1
The matrix of altered habitats that surrounds remnants in human dominated landscapes has been considered homogeneous and inhospitable.
Recent studies, however, have shown the crucial role of the matrix in maintaining diversity in fragmented landscapes, acting
as a mosaic of units with varying permeability to different species. Inclusion of matrix quality parameters is especially
urgent in managing fragmented landscapes in the tropics where agriculture frontiers are still expanding. Using standardized
surveys in 23 sites in an Atlantic forest landscape, we evaluated matrix use by small mammals, the most diverse ecological
group of mammals in the Neotropics, and tested the hypothesis that endemic species are the most affected by the conversion
of original forest into anthropogenic habitats. By comparing species distribution among forest remnants and the predominant
adjacent habitats (native vegetation in initial stages of regeneration, eucalyptus plantations, areas of agriculture and rural
areas with buildings), we found a strong dissimilarity in small mammal assemblages between native vegetation (including initial
stages) and anthropogenic habitats, with only two species being able to use all habitats. Endemic small mammals tended to
occupy native vegetation, whereas invading species from other countries or open biomes tended to occupy areas of non-native
vegetation. Our results highlight that future destruction of native vegetation will favor invading or generalist species which
could dominate highly disturbed landscapes, and that some matrix habitats, such as regenerating native vegetation, should
be managed to increase connectivity among populations of endemic species. 相似文献
14.
It is often stated that plants remove air pollutants from the urban atmosphere with their large leaf area, thus providing benefits − i.e. ecosystem services − for citizens. However, empirical evidence showing that local-scale air quality is uniformly improved by urban forests is scarce. We studied the influence of conifer-dominated peri-urban forests on the springtime levels of NO2 and particle pollution at different distances from roads, using passive samplers and high time resolution particle counters in a northern climate in Finland. Passive samplers provided average values over a one month period, while active particle counters provided real time measurements of air pollution to mimic human inhalation frequency. NO2 concentrations were slightly higher in forests than in adjacent open areas, while passive particle measurements showed the opposite trend. Active particle monitoring campaigns showed no systematic forest effect for PM2.5, but larger particles were reduced in the forest, corroborating the passive sampling result.Attenuation rates of the mean values of the studied pollutants did not differ between the forest and open habitats. However, high time resolution particle data revealed a distance effect that was apparent only in the forest transect: peak events at the forest edge were higher, while peaks furthest from the road were lower compared to the open transect. Furthermore, the magnitude of PM2.5 peak events was distinctly higher at forest edge than equivalent distance in the open area.Vegetation characteristics, such as canopy cover and tree density, did not explain differences in pollutant levels in majority of cases. Our results imply that evergreen-dominated forests near roads can slightly worsen local air quality regarding NO2 and PM2.5 in northern climates, but that coarser particle pollution can be reduced by such forest vegetation. It seems that the potential of roadside vegetation to mitigate air pollution is largely determined by the vegetation effects on airflow. 相似文献
15.
Biodiversity and ecological value of conservation lands in agricultural landscapes of southern Ontario,Canada 总被引：1，自引：0，他引：1
In eastern North America, large forest patches have been the primary target of biodiversity conservation. This conservation
strategy ignores land units that combine to form the complex emergent rural landscapes typical of this region. In addition,
many studies have focussed on one wildlife group at a single spatial scale. In this paper, studies of avian and anuran populations
at regional and landscape scales have been integrated to assess the ecological value of agricultural mosaics in southern Ontario
on the basis of the maintenance of faunal biodiversity. Field surveys of avian and anuran populations were conducted between
2001 and 2004 at the watershed and sub-watershed levels. The ecological values of land units were based on a combination of
several components including species richness, species of conservation concern (rarity), abundance, and landscape parameters
(patch size and connectivity). It was determined that habitats such as thicket swamps, coniferous plantations and cultural
savannas can play an important role in the overall biodiversity and ecological value of the agricultural landscape. Thicket
swamps at the edge of agricultural fields or roads provided excellent breeding habitat for anurans. Coniferous plantations
and cultural savannas attracted many birds of conservation concern. In many cases, the land units that provided high ecological
value for birds did not score well for frogs. Higher scores for avian and anuran populations were recorded along the Niagara
Escarpment and other protected areas as expected. However, some private land areas scored high, some spatially connected to
the protected areas and therefore providing an opportunity for private land owners to enter into a management arrangement
with the local agencies. 相似文献
16.
Philip S. Barton Karen Ikin Annabel L. Smith Christopher MacGregor David B. Lindenmayer 《Landscape Ecology》2014,29(4):703-714
Ecological theory predicting the impact of fire on ecological communities is typically focused on post-disturbance recovery processes or on disturbance-diversity dynamics. Yet the established relationship between vegetation structure and animal diversity could provide a foundation to predict the short-term effects of fire on biodiversity, but has rarely been explored. We tested the hypothesis that fire effects on bird assemblages would be moderated by increasing vegetation structure. We examined bird assemblages in burnt and unburnt sites at 1 and 6 years after a wildfire, and compared richness and composition responses among and within three structurally distinct vegetation types in the same landscape: heath, woodland and forest. We found that short-term changes in bird assemblage composition were largest in simple heath vegetation and smallest in complex forest vegetation. The short-term change in species richness was larger in forest than in heath. We also found that among-site assemblage variability was greater shortly after fire in heath and woodland vegetation compared with forest vegetation. Our results indicate that complexity in vegetation structure, particularly overstorey cover, can act as an important moderator of fire effects on bird assemblages. Mechanisms for this response include a greater loss of structure in vegetation characterised by a single low stratum, and a proportionally greater change in bird species composition despite a smaller absolute change in species richness. We discuss our results in the context of a new conceptual model that predicts contrasting richness and composition responses of bird assemblages following disturbance along a gradient of increasing vegetation structure. This model brings a different perspective to current theories of disturbance, and has implications for understanding and managing the effects of fire on biodiversity in heterogeneous landscapes. 相似文献
17.
Wetland and pond hydric vegetation is impacted across the rural, peri-urban, and urban zones by anthropogenic activities such as agricultural production, industrial manufacturing, and urban development. Previous studies have assessed urban and rural wetland vegetation, but have rarely explored the peri-urban zone of development. Therefore, to investigate the impacts of urbanization on hydric vegetation, thirty pond sites (10 rural, 10 peri-urban, and 10 urban) were randomly selected within each of the three zones. The vegetation community at each site was assessed using a quadrat method to compare the vegetation composition. In addition, floristic quality based on the conservatism value of each plant species was used to assess wetland vegetation. Results show plant communities of rural sites differed from both urban and peri-urban sites due partly to urbanization reducing the cover of obligate wetland species. Peri-urban sites contained the highest species richness, due to the increase in introduced plants associated with urbanization. Urban sites contained the lowest species richness, some of which is due to the use of rock riprap surrounding the edges of most sites. The plant conservatism values of vegetation were not different for rural and peri-urban sites, but were significantly lower in urban sites. Information from this study is useful to wetland professionals, environmental managers, and urban planners to predict hydric vegetation responses within peri-urban areas in the Prairie Pothole Region. 相似文献
18.
Victor A. Rudis 《Landscape Ecology》1995,10(5):291-307
In human-dominated regions, forest vegetation removal impacts remaining ecosystems but regional-scale biological consequences and resource value changes are not well known. Using forest resource survey data, I examined current bottomland hardwood community types and a range of fragment size classes in the south central United States. Analyses examined resource value indicators, appraised tree-based flood zone and shade tolerance indices, and identified potential regional-scale processes. Findings revealed that the largest fragments had fewer tree species, reduced anthropogenic use evidence, and more older and wetter community types than small fragments. Results also suggested the need for incorporating hydrologic, geomorphic, and understory vegetation parameters in regional forest resource monitoring efforts.Two regional-scale processes are hypothesized: (1) forest fragmentation occurs more frequently in drier habitats and dry zone (inundated 2 months annually), younger seral stage bottomland community types; and (2) forest fragmentation induces establishment of drier habitats or dry zone, younger serai stage community types. Both hypotheses suggest that regional forest fragmentation impacts survival of distinct community types, anthropogenic uses, and multiple resource values. 相似文献
19.
The planning and management of urban forest has become increasingly important as a focus of urban environmental management. The objectives of this study were to analyze the landuse/land cover and to map functional zones of the urban forest in the upper catchment area of Addis Ababa. This study identifies five landuse/land cover types: (i) Eucalyptus–Juniperus dominated forest, (ii) mixed native forest, (iii) built-up areas, (iv) Eucalyptus plantation (v) crop/grazing lands. The vegetation analysis shows 44 woody plant species representing 31 families, out of which 13 tree species, 29 shrubs and two species of lianas. The woody species diversity was 1.35 with the species richness and evenness of 44 and 0.80, respectively. This indicates that the forest has poor species diversity which is attributed to high anthropogenic pressure and monoculture plantation development strategies in the last decades. The density of plants ranged from 25 for Olea europea to 825 individuals per hectare for Eucalyptus globules from the tree layers and from 50 for Dombeya torrida and Erica arborea to 900 individuals per hectare for Myrsine africana from shrub layers. Based on importance value index (IVI), Eucalyptus globulus and Juniperus procera showed the highest IVI of 96.37 and 54.80, respectively as compared to other species. The forest structure showed higher contagious distribution where out of the recorded 44 species, 37 species showed contagious distribution. The result also showed poor regeneration potential in all studied forest layers. Based on the landuse/cover analysis, the phytosociological study and field observation, this study recommends six urban forest zoning. These include: (i) conservation zone, (ii) recreation zone, (iii) production zone, (iv) agroforestry zone, (v) reforestation zone, (vi) buffer zone between the green area and the built-up environment. The green area in the upper catchment has no definite boundaries and needs re-demarcation activities. 相似文献
20.
Edge and area effects on avian assemblages and insectivory in fragmented native forests 总被引：1，自引：1，他引：0
Luc Barbaro Eckehard G. Brockerhoff Brice Giffard Inge van Halder 《Landscape Ecology》2012,27(10):1451-1463
Disentangling the confounded effects of edge and area in fragmented landscapes is a recurrent challenge for landscape ecologists, requiring the use of appropriate study designs. Here, we examined the effects of forest fragment area and plot location at forest edges versus interiors on native and exotic bird assemblages on Banks Peninsula (South Island, New Zealand). We also experimentally measured with plasticine models how forest fragment area and edge versus interior location influenced the intensity of avian insectivory. Bird assemblages were sampled by conducting 15?min point-counts at paired edge and interior plots in 13 forest fragments of increasing size (0.5?C141?ha). Avian insectivory was measured as the rate of insectivorous bird attacks on plasticine models mimicking larvae of a native polyphagous moth. We found significant effects of edge, but not of forest patch area, on species richness, abundance and composition of bird assemblages. Exotic birds were more abundant at forest edges, while neither edge nor area effects were noticeable for native bird richness and abundance. Model predation rates increased with forest fragmentation, both because of higher insectivory in smaller forest patches and at forest edges. Avian predation significantly increased with insectivorous bird richness and foraging bird abundance. We suggest that the coexistence of native and exotic birds in New Zealand mosaic landscapes enhances functional diversity and trait complementation within predatory bird assemblages. This coexistence results in increased avian insectivory in small forest fragments through additive edge and area effects. 相似文献