共查询到20条相似文献，搜索用时 31 毫秒
1.
Anette Edvardsen Rune Halvorsen Ann Norderhaug Oddvar Pedersen Knut Rydgren 《Landscape Ecology》2010,25(7):1071-1083
Habitat specificity analysis provides a tool for partitioning landscape species diversity on landscape elements by separating
patches with many rare specialist species from patches with the same number of species, all of which are common generalists
and thus provide information of relevance to conservation goals at regional and national levels. Our analyses were based upon
species data from 2201 patch elements in SE Norwegian modern agricultural landscapes. The context used for measuring habitat
specificity strongly influences the results. In general the gamma diversity contribution and core habitat specificity calculated
from the patch data set were correlated. High values for both measures were observed for woodland, pastures and road verges
whereas midfield islets and boundary transitional types were ranked low, as opposed to findings in traditional, extensively
managed agricultural landscapes. This is due to our study area representing intensively used agricultural landscape elements
holding a more trivial species composition, in addition to ruderals being favoured by fertility and disturbance, a finding
also being supported by the semi-natural affiliation index. Results obtained by use of checklist data from the same study
area diverged from patch data. Caution is needed in interpretation of habitat specificity results obtained from checklist
data, because modern agricultural landscapes contain several land types which are seldom surveyed by botanists, thus being
under-represented in the data set. We propose the use of core habitat specificity and gamma diversity contribution in parallel
to obtain a value neutral diversity assessment that addresses patch uniqueness and other properties of conservation interests. 相似文献
2.
We conducted two studies on how highways affect their adjacent habitats by sampling carabid beetles (Coleoptera, Carabidae)
in patches of formerly continuous forest next to highways. (1) We sampled carabids at 14 highway intersections near Helsinki,
Finland. Each intersection (constructed 2–40 years ago) had two forested patches to study: a remnant (0.5–37.4 ha) and, isolated
from the remnant by an intersection lane, an islet (size 0.2–1.8 ha). Pitfall trap catch data (2301 carabids, 25 species)
showed that remnants hosted higher catches of three carabid species, and slightly higher species richness, than islets (patch-size
effect). Time since intersection construction had no apparent effect on carabids. Traffic volume along the intersection lane
determined the assemblage structure of carabids in dry patches, and the abundance of a forest carabid Calathus micropterus. Compared to moist patches, drier patches hosted lower catches of four generalist species; they also had different assemblages
of carabids (habitat-type effect). An interaction between patch size and habitat type for a forest generalist Pterostichus oblongopunctatus indicated that the patch-size effect was dependent on habitat type. (2) We examined possible dispersal of carabids among
forested patches that were separated by highway lanes in Drenthe, the Netherlands. We released 2696 marked individuals of
10 species, and recaptured 376 using dry pitfall traps. We found no evidence for inter-patch movement for nine forest species,
but 22 of 225 recaptured individuals of Poecilus versicolor, an eurytopic open-habitat species, had crossed the highway. Catches of seven forest species were also significantly lower
in the road verges, compared to the adjacent forests. These two studies suggest that (i) decreasing patch size negatively
affects forest-carabid catch and overall species richness, (ii) habitat type can affect the intensity of the patch-size effect,
(iii) carabid assemblages of forest fragments vary with traffic volume (which may be linked with urbanization), (iv) forest
carabids rarely cross highways, and (v) open habitats associated with road margins are dispersal barriers for forest carabids. 相似文献
3.
Disturbed habitats are often swiftly colonized by alien plant species. Human inhabited areas may act as sources from which
such aliens disperse, while road verges have been suggested as corridors facilitating their dispersal. We therefore hypothesized
that (i) houses and urban areas are propagule sources from which aliens disperse, and that (ii) road verges act as corridors
for their dispersal. We sampled presence and cover of aliens in 20 plots (6 × 25 m) per road at 5-km intervals for four roads,
nested within three localities around cities (n = 240). Plots consisted of three adjacent nested transects. Houses (n = 3,349) were mapped within a 5-km radius from plots using topographical maps. Environmental processes as predictors of alien
composition differed across spatial levels. At the broadest scale road-surface type, soil type, and competition from indigenous
plants were the strongest predictors of alien composition. Within localities disturbance-related variables such as distance
from dwellings and urban areas were associated with alien composition, but their effect differed between localities. Within
roads, density and proximity of houses was related to higher alien species richness. Plot distance from urban areas, however,
was not a significant predictor of alien richness or cover at any of the spatial levels, refuting the corridor hypothesis.
Verges hosted but did not facilitate the spread of alien species. The scale dependence and multiplicity of mechanisms explaining
alien plant communities found here highlight the importance of considering regional climatic gradients, landscape context
and road-verge properties themselves when managing verges.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
4.
River floodplains are among the most threatened ecosystems globally. Understanding the mechanisms that create and maintain biodiversity and ecosystem functioning of floodplains, is therefore a prerequisite for developing scientifically-sound management and conservation strategies. We quantified the spatial distribution of lateral aquatic habitats (i.e. tributaries, ponds, backwaters) and the associated insect assemblages (Ephemeroptera, Plecoptera, Trichoptera) along three Alpine river corridors (Tagliamento, Thur, and Rhône). Our objective was to assess the relative contribution of lateral habitats to river corridor diversity, and to identify the scale that contributed the most to regional (Alpine scale) species diversity. The number of lateral habitats decreased by 72 % from the near-natural Tagliamento (101) to the Thur river (42) and the regulated Rhône river (28). More than 50 % of the total species richness along each river was restricted to lateral habitats, which also exhibited higher taxon turnover rates (Whittaker’s beta diversity) than the associated main channel. Hierarchical diversity partitioning revealed that beta diversity among corridors was higher than expected, and accounted for 48 % of regional richness, partly reflecting biogeographical differences among catchments. However, diversity partitioning, excluding catchment-specific effects, showed that beta diversity among habitat types contributed significantly to regional richness (79 %). The present study is among the first to quantify the distribution and biodiversity of floodplain habitats along entire river continua. Our results demonstrated that biodiversity would be best preserved by protecting multiple catchments, and that lateral floodplain habitats contribute disproportionally to species richness at the river corridor and regional scale. 相似文献
5.
The spatial extent and relative influence of landscape-level factors on wintering bird populations 总被引：5，自引：0，他引：5
Scott M. Pearson 《Landscape Ecology》1993,8(1):3-18
The influences of the landscape matrix (complex of habitats surrounding a study plot) and within-patch vegetation were studied in bird communities wintering in the piedmont of Georgia, USA. Variation at the landscape and within-patch levels was controlled to reduce the likelihood of confounding and spurious relationships. The landscape matrix within 500 m of each study plot was quantified from aerial photographs. Statistical models using landscape matrix and within-patch vegetation variables explained 73–84% of variation in bird abundance and diversity among sites with landscape matrix variables accounting for 30–90% of the variation. Variation in bird species richness and diversity was explained solely by landscape variables. Models for individual species such as Carolina Wrens (Thyrothorus ludovicianus) and Rufous-sided Towhees (Pipilo erythrophthalmus) had r2 > 0.80, with the landscape matrix variables accounting for the majority of this variation. However, other species like Northern Cardinals (Cardinalis cardinalis) and White-throated Sparrows (Zonotrichia albicollis) were most strongly influenced by within-plot vegetation. The landscape influence extended beyond habitats immediately adjacent to the study plots as indicated by significant variables describing variation in more distant habitat patches. These analyses illustrate a technique for comparing the strength of within-patch versus landscape influences and measuring the spatial extent of the landscape influence in fine-grained landscapes.Report No. 3955, Environmental Sciences Division, Oak Ridge National Laboratory.This research received funding from the Ecological Research Division, Office of Health and Environmental Research, U.S. Department of Energy, under Contract No. DE-AC05-84OR21400 with Martin Marietta Energy Systems, Inc. 相似文献
6.
Habitat loss and fragmentation of natural and semi-natural habitats are considered as major threats to plant species richness.
Recently several studies have pinpointed the need to analyse past landscape patterns to understand effects of fragmentation,
as the response to landscape change may be slow in many organisms, plants in particular. We compared species richness in continuously
grazed and abandoned grasslands in different commonplace rural landscapes in Sweden, and analysed effects of isolation and
area in three time-steps (100 and 50 years ago and today). Old cadastral maps and aerial photographs were used to analyse
past and present landscape patterns in 25 sites. Two plant diversity measures were investigated; total species richness and
species density. During the last 100 years grassland area and connectivity have been reduced by about 90%. Present-day habitat
area was positively related to total species richness in both habitats. There was also a relationship to habitat area 50 years
ago for continuously grazed grasslands. Only present management was related to species density: continuously grazed grasslands
had the highest species density. There were no relationships between grassland connectivity, present or past, and any diversity
measure. We conclude that landscape history is not directly important for present-day plant diversity patterns in ordinary
landscapes, although past grassland management is a prerequisite for the grassland habitats that can be found there today.
It is important that studies are conducted, not only in very diverse landscapes, but also in managed landscapes in order to
assess the effects of fragmentation on species. 相似文献
7.
8.
The study measured landscape level diversity of the understory plants of mature, upland forests in north-central Wisconsin USA. Habitat types were used to segregate the landscape along a moisture-nutrient gradient. Forty sites that had closed canopies, had been undisturbed for at least 20 years, and were at least 8 ha in size were used. The percent cover of groundlayer species was ocularly estimated in 12–18 randomly located, one meter square plots in June and August, 1995. Shrub cover was estimated by the line intercept method. Alpha, beta and gamma diversity were determined for early and late summer periods separately. Gamma diversity was quantified using a new method, affinity analysis, which generates a list of modal and outlier sites and calculates mosaic diversity, a measure of landscape complexity. Generally, communities in the middle of the moisture-nutrient gradient were modal, whereas those at the mesic end of the gradient were outlier. Mosaic diversity values were very similar for early summer and late summer (2.88±0.04, 2.95±0.03, respectively), but was much higher for both periods combined (3.95±0.07). Whittaker's Index (beta diversity) revealed varying rates of species turnover along presumed moisture and nutrient gradients, whereas species densities and richness were relatively constant among habitat types. A one-way analysis of variance of Shannon-Weaver values found no significant differences among habitat types (p0.05). Regional diversity mainly resulted from high beta values which appears to be primarily a function of the moisture gradient. The other factors influencing compositional differences among sites are variation in site history, especially disturbance, with niche partitioning and differences in seed dispersal capacity having a minor influence. The affinity analysis method indicated that sampling once per season is inadequate, and that many types of sites are modal. This method for estimating gamma (landscape) diversity shows considerable promise, but information on the processes that produce outlier sites is needed to fully understand and use the results of this method. 相似文献
9.
Context
The habitat amount hypothesis has rarely been tested on plant communities. It remains unclear how habitat amount affect species richness in habitat fragments compared to island effects such as isolation and patch size.Objectives
How do patch size and spatial distribution compared to habitat amount predict plant species richness and grassland specialist plant species in small grassland remnants? How does sampling area affect the prediction of spatial variables on species richness?Methods
We recorded plant species density and richness on 131 midfield islets (small remnants of semi-natural grassland) situated in 27 landscapes in Sweden. Further, we tested how habitat amount, compared to focal patch size and distance to nearest neighbor predicted species density and richness of plants and of grassland specialists.Results
A total of 381 plant species were recorded (including 85 grassland specialist species). A combination of patch size and isolation was better in predicting both density and richness of species compared to habitat amount. Almost 45% of species richness and 23% of specialist species were explained by island biogeography parameters compared to 19 and 11% by the amount of habitat. A scaled sampling method increased the explanation level of island biogeography parameters and habitat amount.Conclusions
Habitat amount as a concept is not as good as island biogeography to predict species richness in small habitats. Priority in landscape planning should be on larger patches rather than several small, even if they are close together. We recommend a sampling area scaled to patch size in small habitats.10.
Additive partitioning of plant species diversity in an agricultural mosaic landscape 总被引：14，自引：1，他引：13
In this paper, we quantify the effects of habitat variability and habitat heterogeneity based on the partitioning of landscape species diversity into additive components and link them to patch-specific diversity. The approach is illustrated with a case study from central Switzerland, where we recorded the presence of vascular plant species in a stratified random sample of 1'280 quadrats of 1 m2 within a total area of 0.23 km2. We derived components of within- and between-community diversity at four scale levels (quadrat, patch, habitat type, and landscape) for three diversity measures (species richness, Shannon index, and Simpson diversity). The model implies that what we measure as within-community diversity at a higher scale level is the combined effect of heterogeneity at various lower levels. The results suggest that the proportions of the individual diversity components depend on the habitat type and on the chosen diversity aspect. One habitat type may be more diverse than another at patch level, but less diverse at the level of habitat type. Landscape composition apparently is a key factor for explaining landscape species richness, but affects evenness only little. Before we can test the effect of landscape structure on landscape species richness, several problems will have to be solved. These include the incorporation of neighbourhood effects, the unbiased estimation of species richness components, and the quantification of the contribution of a landscape element to landscape species richness. 相似文献
11.
Calcareous grasslands are among the most species-rich ecosystems in temperate countries. However, these ecosystems have suffered
from fragmentation and destruction during the last century. We studied the response of calcareous grassland plant diversity
to landscape changes in Belgium. Results indicated that high area loss (since 1965) old habitat patches exhibited an extinction
debt inverse to low area loss old habitat patches, little depending on the area loss threshold (60%, 70%, 80% or 90%) considered
for the distinction between the high and low area loss patches. However, human activities also created new habitat patches
in the landscape and therefore provided opportunities for calcareous grassland plant species to colonize new habitats. This
also provided opportunities to study species colonization abilities in the context of habitat restoration. We analyzed species
richness in new patches compared to old patches in order to detect colonization credit. We detected the presence of a colonization
credit in new patches when using high loss old patches (area loss >80%, exhibiting an extinction debt) or all old patches
as a reference. However, when the reference was low loss old patches alone (area loss <80%, less likely to exhibit an extinction
debt), no colonization credit was detected. In addition, species composition was similar between new patches and old patches.
These results are encouraging for restoration programs. However, the results indicated that the presence of an extinction
debt in reference habitats could lead to inaccurate conclusions in restoration monitoring. Therefore, extinction debt should
be considered when choosing reference habitats to evaluate restoration success. 相似文献
12.
Influence of within-field and landscape factors on aphid predator populations in wheat 总被引：3，自引：0，他引：3
Elliott Norman C. Kieckhefer Robert W. Lee Jang-Hoon French Bryan W. 《Landscape Ecology》1999,14(3):239-252
The influence of prey density, within-field vegetation, and the composition and patchiness of the surrounding landscape on the abundance of insect predators of cereal aphids was studied in wheat fields in eastern South Dakota, USA. Cereal aphids, aphid predators, and within-field vegetation were sampled in 104 fields over a three year period (1988–1990). The composition and patchiness of the landscape surrounding each field were determined from high altitude aerial photographs. Five landscape variables, aggregated at three spatial scales ranging from 2.6 km2 to 581 km2, were measured from aerial photographs. Regression models incorporating within-field and landscape variables accounted for 27–49% of the variance in aphid predator abundance in wheat fields. Aphid predator species richness and species diversity were also related to within-field and landscape variables. Some predators were strongly influenced by variability in the composition and patchiness of the landscape surrounding a field at a particular spatial scale while others responded to variability at all scales. Overall, predator abundance, species richness, and species diversity increased with increasing vegetational diversity in wheat fields and with increasing amounts of non-cultivated lands and increasing patchiness in the surrounding landscape. 相似文献
13.
Annual plant species have great potential on green roofs as many are highly attractive, fast and cheap to establish via sowing and can provide rapid cover and growth, which is important for ecosystem service provision. While irrigation is essential for survival and growth of annual plants in seasonally hot or dry climates, it is also important to minimize water use as availability is often limited. Therefore, we evaluated how irrigation frequency affects plant cover, species abundance, richness and diversity, plant traits and functional diversity of a 16 species mixture of Australian annual species (4 g m−2 ~ 2100 seeds m−2) sown onto thirty 0.25 m2 green roof modules. The experiment was carried out in Melbourne, Australia, from January (summer) to July (winter) 2020. After a 2-month irrigated establishment phase (to ensure germination and seedling establishment), three irrigation treatments (2, 4 and 6 days between irrigation) were applied to the modules for three months. Plant cover was reduced at lower irrigation frequency (6 days), but ≥ 80% plant cover was achieved in all irrigation treatments. There was no effect of irrigation frequency on species abundance and richness; however, abundance, richness and diversity reduced over time, likely due to competition effects. Plant height and leaf area were also reduced by lower irrigation frequency. At the community level, functional diversity was unaffected by irrigation frequency. Our results indicate that green roofs sown with a mixture of annual plants can achieve good plant coverage, as recommended by green roof guidelines, and maintain high diversity when minimally irrigated in their first growing season. 相似文献
14.
Although urban habitats contribute to the conservation of species diversity, urbanization has significantly reduced biodiversity by causing environmental changes such as habitat loss and fragmentation. Therefore, research on urban biodiversity studies has become increasingly important. Historical heritage sites are recognized as important habitats in remnant green spaces in urban areas. We aimed to evaluate the role of historical sites in conserving biodiversity in urban areas. As the land in these historical sites is not modified, they have the potential to conserve biodiversity through continued maintenance activities such as mowing and tree cutting. In Japan, Tamagawa-josui, a waterway that runs from west to east through the Tokyo megacity (35° 40′ N, 139° 25′ E), has been recognized as a civil engineering heritage landmark that preserves water utilization technology from the early modern period (1600s, Edo-era). The present study examined the relationships between plant diversity and green space in a historic site of a megacity (i.e., Tamagawa-josui) and determined the factors that influence plant diversity. Specifically, we examined the relationships between plant species indices (species richness and species compositions) and environmental factors (management, environmental conditions, and landscape factors). The present study analyzed spatial changes in the plant species composition in Tamagawa-josui. We demonstrated that tree canopy openness was positively correlated with plant species richness, and the increased disturbance associated with developing historical sites as urban parks was negatively correlated with native plant species richness. In addition, there was significant species turnover in the plant community from upstream to downstream in Tamagawa-josui, which could largely be explained by spatial factors. We demonstrated that historical sites can provide potential habitats for the conservation of the plant species diversity, which is based on the effectiveness of the management of their vegetation. 相似文献
15.
Facing the trend of rapid urbanization, conserving the biodiversity of urban green spaces is a challenge, particularly in a developing region like Latin America. In this sense, it is known that urban sacred sites have significant cultural and conservation significance within cities. However, more needs to be studied about the vegetation they house. Given the scientific gap, the composition, richness and abundance of trees in urban religious sites of Arequipa established since the 16th century were examined, and temporal changes in the composition and distribution of trees between ancient and modern sites were identified. 749 trees of 54 species were recorded in 26 religious’ sites. A higher proportion of exotic species (74%) corresponds in greater quantity to fruit trees (52%). There were no significant differences in tree richness and abundance between ancient and modern sites. However, the ancient sites had higher richness (96.3%) and abundance (71.4%). Likewise, ancient sites present a preference for growing fruit trees in orchards and cloister gardens, unlike modern sites focused on increasing ornamental trees, with a predominance of conifers and palms. Despite the long history of the monuments, the size of the site and the green areas significantly influenced the richness and abundance; similarly, the care of the gardens greatly influenced a site that stored greater diversity and abundance. In this way, it is demonstrated that these culturally significant places house an important tree diversity, with species of nutritional and ornamental value for the self-provisioning of the religious and the beautification of the gardens. In addition, they contribute to environmental sustainability, providing different ecosystem services to cities with rapid population growth. 相似文献
16.
Habitat specificity indices reflect richness (α) and/or distinctiveness (β) components of diversity. The latter may be defined by α and γ (landscape) diversity in two alternative ways: multiplicatively () and additively (). We demonstrate that the original habitat specificity concept of Wagner and Edwards (Landscape Ecol 16:121–131, 2001) consists of three independent components: core habitat specificity (uniqueness of the species composition), patch area and
patch species richness. We describe habitat specificity as a family of indices that may include either area or richness components,
or none or both, and open for use of different types of mean in calculation of core habitat specificity. Core habitat specificity
is a beta diversity measure: the effective number of completely distinct communities in the landscape. Habitat specificity
weighted by species number is a gamma diversity measure: the effective number of species that a patch contributes to landscape
richness. We compared 12 habitat specificity indices by theoretical reasoning and by use of field data (vascular plant species
in SE Norwegian agricultural landscapes). Habitat specificity indices are strongly influenced by weights for patch area and
patch species richness, and the relative contribution of rare vs. common species (type of mean). The relevance of properties
emphasized by each habitat specificity index for evaluation of patches in a biodiversity context is discussed. Core habitat
specificity is emphasized as an ecologically interpretable measure that specifically addresses patch uniqueness while habitat
specificity weighted by species number combines species richness and species composition in ways relevant for conservation
biological assessment.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
17.
The role of linear habitat strips as dispersal corridors is a disputed topic. Reports concerning their significance for animals have been contradictory, and the functions of corridors have been difficult to study in the case of sedentary organisms such as plants. Previous studies on dispersal of plants along corridors have concentrated on a single or a few species at a time. We developed a general method, a generalisation of the binomial test, for considering dispersal or spatial relations of a large group of species. Particularly, we studied the ability of grassland plants to spread along road and railway verges. Our data set consists of plant lists collected at study plots scattered irregularly along road and railway networks. The dispersal ability was assessed by testing whether the species composition at neighbouring sites – measured along roads and railways – reflects spatial dependence within each species. Our result showed that similar combinations of grassland species occurred at neighbouring sites more often than expected in a spatially independent case. We argue that management of verges and spatial autocorrelation of environmental factors were not responsible for the result and thereby we conclude that grassland plants use road and railway corridors for dispersal. This result is encouraging in regards to preservation of grassland plant populations. Although semi-natural and natural grasslands have become scarce, road and railway embankments may partly compensate for this loss, serving as substitute habitats and dispersal routes. 相似文献
18.
Alberto Suárez-Esteban Lenore Fahrig Miguel Delibes José M. Fedriani 《Landscape Ecology》2016,31(4):721-729
Context
Seed-dispersing animals often move along “linear gaps” (linear anthropogenic features such as roads and trails that contain little vegetation), especially in densely-vegetated landscapes. As a result, linear gaps and their verges may receive more seeds than adjacent habitats. In addition, linear gap verges may provide more suitable conditions for plant establishment than neighboring habitats. In this way, linear gaps may increase plant abundance and diversity, and facilitate connectivity of native and non-native plant populations, ultimately increasing plant diversity in the landscape.Objectives
We reviewed current evidence for the potential of anthropogenic linear gaps to increase plant abundance and diversity, and for the mechanisms involved.Methods
We reviewed peer-reviewed literature published up to December 31st, 2014.Results
Most (69.2 %) studies found significantly higher plant abundance and/or diversity in linear gap verges than in adjacent habitats. This suggests that linear gaps can increase plant abundance and diversity, and possibly facilitate population spread. However, there was a strong bias toward the study of exotic species. In addition, there were few mechanistic studies to allow estimation of the relative contributions of dispersal and post-dispersal mechanisms operating in linear gaps.Conclusions
Future studies should focus on entire plant communities, not just exotic species, and should allow identification of the mechanisms by which linear gaps increase plant abundance and diversity. With this knowledge in hand, we will be in a better position to understand whether the net benefit of linear gaps for plant diversity in general outweigh their facilitation of the spread of exotic species.19.
为了明确西藏地区果园昆虫种类组成及多样性,对该地区果园昆虫种类、数量进行了系统调查,分析探讨了西藏地区低、中、高3个不同海拔区域果园昆虫群落的组成、群落丰富度、多样性、均匀度和优势度等特征。结果表明,在不同海拔的昆虫种类组成具有明显差异。调查共采集到昆虫标本877个,隶属13目47科71种,其中,低海拔地区共51种,占比71.83%;中海拔地区17种,占比23.94%;高海拔地区11种,占比15.49%。低海拔地区物种丰富度最高,为7.7344,高海拔地区最低,为2.1762;昆虫群落物种多样性、群落均匀度、群落相似性也随海拔的升高而降低,而优势集中度则随海拔升高而增大。在果园生态系统中,不同海拔生产者(果树种类)垂直分布的不同,消费者(果树昆虫,包括害虫及天敌)的组成及多样性亦不同;西藏东南部地区果园昆虫在低海拔生境中群落较为丰富,多样性指数、均匀度最高;高海拔地区群落优势度最高。 相似文献
20.
Understanding the determinants of hedgerow plant diversity in agricultural landscapes remains a difficult task, because the
potential drivers affect the complete range of biodiversity components (alpha to gamma diversity). We surveyed herbaceous
plant communities (of a height <1.5 m) in 84 hedgerows in the Seine river floodplain of France. Two types of potential drivers
for species richness, accounting for landscape mosaic and hedgerow network, were recorded at both hedgerow and site scale.
The distribution of species richness through the components of alpha hedgerow diversity (i.e. the average diversity within
a habitat) and gamma hedgerow diversity (i.e. the total diversity across habitats) were assessed using additive partitioning
methods, while the relationship between species diversity and its potential landscape drivers at both scales was modeled using
Generalized Additive Models. Our results indicated that gamma hedgerow diversity is explained by the heterogeneity of the
landscape structure, which is correlated with the mosaic of agricultural land use. At this scale, intrinsic properties of
the configuration of the hedgerow networks have a weak influence on species richness. Alpha hedgerow diversity is also explained
by landscape variables, accounting for both the configuration of agricultural mosaics and hedgerow networks, but to a lesser
extent. Time lags for species responses are shown at both scales, and for the two types of drivers. Extinction or colonization
debt may be indicated at both scales, while the remnant effects of former practices may also be responsible for such patterns
at a local scale. We suggest that hedgerow management should take the specific parameters of both scales into account. At
a local scale, management actions should aim to decrease the influence of adjacent land use when the impact is negative, through
the implementation of extended buffer zones, while at the landscape and farm scales, agri-environmental schemes should be
dedicated to the conservation of specific agricultural land uses. 相似文献