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1.
Tropical forest trees that produce large fruits and/or large seeds are believed to be dependant on a few and often rare large vertebrates for dispersal. However, little is known about the population dynamics of such trees when they lose their specialised dispersers. This study examines the juvenile spatial distribution of Balanites wilsoniana, Dawe & Spraque, which is believed to be dependant solely on elephants for dispersal, in forests with and without elephants. Using camera traps, elephants were confirmed to be the only frugivores feeding and thus dispersing Balanites wilsoniana fruits. There was a high density of seedlings beneath adult trees in one forest without elephants, which was attributed to low seed and seedling predation in this forest. Nevertheless, it was only in the forest with elephants that juveniles were established away from adult trees. Analysis of the spatial distribution of these juveniles by size revealed that saplings and poles are more likely to be found away from adult trees thus providing evidence that dispersal enhances juvenile survival. This study underlines the importance of seed dispersal for trees that cannot maintain their populations through seedlings germinating and surviving beneath adult conspecifics. The study also demonstrates that loss of vertebrates has ramifications for tree species dynamics above and beyond loss of seed dispersers.  相似文献   

2.
Forests fragmentation reduces the density of natural plant populations forming patches of the remaining individuals. One of the biotic interactions that can be affected by forest fragmentation and is poorly studied is seed predation. We determined the effects of forest fragmentation on seed and fruit predation in Ceiba aesculifolia by comparing trees in continuous forest with trees in fragmented forest. We compared the following variables: (a) frequency of fruit predation by Collie’s squirrel (Sciurus colliaei) in each habitat; (b) frequency of the cotton-staining bug seed predator (Dysdercus, Orden Hemiptera) in each habitat; (c) the effect of seed predation on germination frequency and time; and (d) the effect of different life stages of Dysdercus on seed viability. In continuous habitat, 100% of the trees presented fruits with squirrel predation while only 34% of trees in fragmented habitats presented fruit predation. In continuous forest 27% of the trees contained fruits with the seed predator Dysdercus, while only 2% of the trees in fragmented forest presented Dysdercus. The initial weight of damaged seeds was greater than seeds that were not damaged indicating that seed predators select heavier seeds to feed upon. Frequency of seed germination was affected by different life stages; pre-adults decreased germination significantly more than nymphs and adults. Seed predation significantly increased the time it took for germination to occur. Our study shows that forest fragmentation significantly affects predation patterns of squirrels and cotton-staining bugs. Reduction of natural seed predators in forest fragments may have long-term consequences on forest structure and diversity.  相似文献   

3.
The establishment of plant species depends crucially on where the seeds are deposited. However, since most studies have been conducted in continuous forests, not much is known about the effects of forest fragmentation on the maintenance of abiotic and biotic characteristics in microhabitats and their effects on seed survival. In this study, we evaluated the effects of forest fragmentation on the predation upon the seeds of the palm Syagrus romanzoffiana in three microhabitats (interior forest, forest edge and gaps) in eight fragments of semi-deciduous Atlantic forest ranging in size from 9.5 ha to 33,845 ha in southeastern Brazil. Specifically, we examined the influence of the microhabitat structure, fauna and fragment size on the pattern of seed predation. Fragments <100 ha showed similar abiotic and biotic characteristics to those of the forest edge, with no seed predation in these areas. Forest fragments 230-380 ha in size did not present “safe sites” for S. romanzoffiana seed survival and showed high seed predation intensity in all microhabitats evaluated. In fragments larger than 1000 ha, the seed predation was lower, with abiotic and biotic differences among gaps, interior forests and forest edges. In these fragments, the survival of S. romanzoffiana seeds was related to squirrel abundance and interior forest maintenance. Based on these results, we concluded that there are no safe sites for S. romanzoffiana seed establishment in medium- and small-sized fragments as result of the biotic and abiotic pressure, respectively. We suggest that on these forest fragments, management plans are needed for the establishment of S. romanzoffiana, such as interior forest improvement and development in small-sized sites in order to minimize the edge effects, and on medium-sized fragments, we suggest post-dispersal seed protection in order to avoid seed predation by vertebrates. Our findings also stress the importance of assessing the influence of forest fragmentation on angiosperm reproductive biology as part of the effective planning for the management of fragmented areas.  相似文献   

4.
The southern Iberian Peninsula is one of the most important refugia of Tertiary relict plant taxa in Europe. Under the present summer-dry climate, relict populations may experience a severely reduced regeneration. We studied the demographic structure, seed set and initial recruitment in relict populations of the endangered tree Frangula alnus subsp. baetica (Rhamnaceae) to evaluate its regeneration potential under the present environmental conditions. Populations are restricted to small riparian forests of Southwest Spanish and North Moroccan mountain ranges. The distribution of fruit crop sizes was highly left-skewed, and a few old trees produced the large bulk of the population seed pool. Bird-mediated seed dispersal appeared inefficient and post-dispersal seed predation by mice was high. Secondary seed transport by elevated creek water flow after winter rains modified the primary seed dispersal, but in consequence most seeds germinated on recently formed sandbanks where seedlings experienced reduced initial growth and survival. The most important mortality factor was desiccation, followed by herbivory. None of 1144 monitored seedlings survived for 2 years. The demographic survey through five populations indicates that drought periods may cause temporal regeneration bottlenecks. Moreover, over the last two decades populations have experienced increasing regeneration problems. Two causes are suggested: (1) browsing pressure from introduced game animals, and (2) the impact of torrential water flow peaks after heavy winter rains, exacerbated by large-scale vegetation slashing in surrounding cork oak forests. We discuss conservation strategies for this and other relict tree species that account for the pecularities of their habitat within the Mediterranean.  相似文献   

5.
The Maulino forest is a unique temperate ecosystem restricted to a small range of the coast of central Chile. This forest harbors many endemic species, and is threatened due to intensive deforestation and fragmentation. Currently the Maulino forest is composed of a suite of small fragments scattered in a landscape dominated by exotic plantations. The fragmentation of the Maulino forest has resulted in a higher abundance of granivores in small forest fragments compared with continuous forest. In order to determine if fragmentation-induced changes in granivore abundance affects the granivory of different size seeds, we experimentally assessed seed predation of a large-seeded species [Nothofagus glauca (Phil.) Krasser] and a small-seeded species [Nothofagus obliqua (Mirbel) Oersted] in the edges and interior of one continuous (large) forest and three small fragments (∼3 ha) surrounded by plantations of the exotic tree Pinus radiata. To determine what kind of granivores are preying upon seeds, seeds of both species were excluded from and exposed to large and small granivores. Granivory was higher in small fragments than in continuous forest, higher in the edges than in the forest interior, and higher upon large than on small seeds. Rodents, which were more abundant in forest fragments, were the main consumers. Thus, fragmentation indeed affects granivory increasing the consumption of seeds by predators inhabiting the Maulino forest remnants or coming from the matrix. This change may affect the future structure of the tree community in forest fragments.  相似文献   

6.
Tropical forest fragmentation affects animal and plant populations in different ways. For plants, early stages (seed to seedling) are more sensitive to habitat alteration than adults, and can shape their future spatial patterns. Therefore, studying how seed germination and seedling growth and survival vary at different spatiotemporal scales enhances our understanding about plant recruitment in fragmented ecosystems. In this study we examine if, and to what extent, recruitment at early life-stages of Xymalos monospora (Monomiaceae), a bird-dispersed Afrotropical tree, differs between and within forest fragments that vary in size, surrounding matrix and microhabitats. Three years of field experiments (2004-2006) in south-east Kenya, revealed that patterns of seed germination and seedling survival and growth were largely inconsistent, both in space and time. Recruitment was not consistently higher in larger or less disturbed fragments. At smaller spatial scales within forest fragments, recruitment was subject to high between-year variation too, with decreased germination in gaps only in the dry year of 2004. However, performance of seeds and seedlings was consistently better away from than under conspecific fruiting trees. Our results imply that fragmented tree populations of X. monospora may become age-structured, or ultimately go extinct, if recruitment fails in subsequent years. This may especially affect populations in small, disturbed forest fragments, where seed dispersal and buffering against stochastic processes are generally reduced. Exotic plantations bordering indigenous forest fragments may provide suitable conditions for native tree recruitment; hence, forest expansion through enrichment planting should be considered in future conservation plans.  相似文献   

7.
Many threatened primates now exist in fragmented forest habitats. The survival of these populations may depend on their ability to utilise agricultural or other matrix habitats between forest fragments, but this is poorly known. Here, we systematically investigate an arboreal primate’s use of a heterogeneous matrix in a fragmented forest landscape: the Angola black-and-white colobus (Colobus angolensis palliatus) in southern Kenya. We used a novel technique, based on semi-structured interviews with local informants, to address the difficulty of sampling relatively rare but important events, such as dispersal between fragments. We found that colobus frequently travelled and foraged in indigenous matrix vegetation (such as mangrove, wooded shrubland and shrubland) up to 4 km from the nearest forest fragments. Agricultural habitats, such as perennial plantation (coconut, mango and cashew nut) were also used by colobus for travelling and foraging (in remnant indigenous trees). The probability of sighting colobus in the matrix increased with the proportion of both tall (>6 m) vegetation cover and food tree cover, but declined with distance from forest habitat. Our findings suggest that certain matrix habitats are important for C. a. palliatus, and that future primate conservation initiatives might benefit from adopting a ‘landscape-level’ approach to habitat management, particularly in fragmented forest systems.  相似文献   

8.
This study documents the proportion of woody plant species having different modes of seed dispersal, and classes of seed and fruit size at 16 Atlantic montane forest plots of southeastern Brazil (23-24° S). These plots represent six chronosequences (from 5-year-old to old-growth forest) of forest regeneration following small-scale shifting agriculture. Our results indicate that there is a gradual but predictable increase in the number of woody plant species relying on vertebrate-mediated seed dispersal in increasingly older plots. Moreover, the percentage of plant species bearing small seeds and fruits (< 0.6 cm in length) was more than halved from earlier to older forest plots, while the percentage of plant species producing middle-sized seeds and fruits at least doubled. Plant species belonging to the Melastomataceae, Myrsinaceae, Rubiaceae and Flacourtiaceae comprised a large proportion of the small-seeded and fruit species (33-53%), and largely occurred in early successional forest plots (5-30 years old). In contrast, species belonging to the Myrtaceae and Lauraceae represented most of the species (51-72%) bearing medium-sized seeds and fruits (0.6-1.5 cm in length), and occurred primarily in the old-growth forests. Shifts in the relative importance of dispersal strategies during the regeneration process of Atlantic montane forest, as well as in diaspore size appear to be related to the balance between early successional and shade-tolerant species associated with particular life forms and plant families. Finally, we discuss the relationships between the species richness of Myrtaceae and Lauraceae trees, seed dispersal by medium to large vertebrates, and possible regeneration scenarios for the Atlantic forest.  相似文献   

9.
Allanblackia parviflora A. Chev. (Clusiaceae Lindley) is an indigenous tree species which is found in the rain forest regions of Ghana. It is a potential candidate fruit tree species being introduced in agroforestry systems. Information on genetic diversity, reproductive biology and fruit yield are not known. Field expeditions to seven populations of Allanblackia parviflora in Ghana were undertaken in 2003–2006 during which fruits were collected from 109 trees for characterization. The species was found to be dioecious. The colour of flowers varied from whitish to reddish. No ecological differences in number of fruits per tree, fruit shape and seed health were observed. However, large variations in fruit size and shape were observed among individual trees sampled. A high heritability (h 2 = 0.822) in fruit size and genetic gain (G = 20.1%) in fruit size for selection of trees with above average fruit size were observed. A positive significant correlation was observed between fruit size and seed weight (R = 0.54, P < 0.05; Fig. 6). The results suggest that selection and cloning of trees with large fruits could lead to higher yield of seeds for oil production.  相似文献   

10.
Many tropical trees bear fruits adapted for consumption by animals, and many tropical animals depend on fruits for food for at least part of the year. The purpose of this paper is to discuss the potential importance of: (1) uneven species abundance distributions; (2) the imperative of local seed dispersal for plant recruitment; and (3) seasonality of fruit production for managing small tropical reserves. Some mutualistic seed-dispersal systems are ‘pivotal’ for forest communities. Although most species of trees produce when other fruits are readily available in the forest, others (e.g. Casearia corymbosa in Costa Rican rainforest and Virola sebifera in Panamanian rainforest) bear fruits during annual periods of fruit scarcity, and consequently maintain species of fruit-eating birds and mammals which are critical for the dispersal and ultimate recruitment of many tree species at other times of the year. The question of relative abundance presents particular problems when ‘pivotal’ plant species are rare or confined to special habitats. This paper considers ecological relationships which accelerate species loss from habitat islands over and above ‘random’ loss of ecologically independent species predicted from biogeographic theory, and suggests management methods that can reduce such excessive loss.  相似文献   

11.
The islands of Tonga, in Western Polynesia, lacked rodents prior to human colonization. During the past 3000 years, people have introduced three species of rats (Rattus). Seed predation by rodents structures plant communities in many parts of the world. Therefore, there is the potential for rats to have a significant impact on the regeneration of plant communities in Tonga. We found 53 husking stations—sheltered sites used by rats to strip inedible protective structures (husks) from the seeds they eat—on eight islands in Tonga. The stations contained 13,555 empty husks from at least 18 plant species, but only 165 viable seeds and seedlings. These husking stations provide evidence of seed predation by rats. Determining the extent to which seed predation threatens plant regeneration will be important for conservation of native forest remnants.  相似文献   

12.
To provide sustainable income from forestlands, large areas in the tropics are planted with “agricultural” trees, such as oil palm and rubber, and “industrial” trees, such as Acacia mangium and Gmelina arborea. To examine how native forest birds use such plantations, we surveyed in 2005 the avifauna at Sabah Softwoods, a plantation in southeastern Sabah, Malaysian Borneo. We focused on A. mangium, Albizia (Paraserianthes falcataria), oil palm (Elaeis guineensis), and logged native forest, and compared our results to those of a study conducted at the same plantation in 1982. The number of forest species in the industrial groves did not change dramatically between 1982 and 2005, even though the trees had been cropped several times and the plantation was, by 2005, completely surrounded by cleared land and far removed from primary forest. However, as is common in logged or isolated forests throughout the world, certain primary forest groups (e.g., muscicapine flycatchers) have been extirpated from the entire plantation area. The industrial groves also lacked some larger species of kingfisher, woodpeckers, and canopy frugivores. Nevertheless, numerous primary forest taxa (ca. 50% of species) were found in mature industrial tree groves. Albizia attracted the most species of birds, followed closely by Acacia. Both tree types underpinned relatively complex secondary forests that attracted forest birds. In contrast, younger groves of Acacia and Albizia held mainly open country and scrub species. Oil palm, as a remarkably simple and unusual habitat, attracted few bird species. Sustained occurrence of forest birds in all groves of exotic trees at Sabah Softwoods was substantially enhanced by the relatively rich avifauna of the logged native forest remaining in substantial stands throughout the plantation.  相似文献   

13.
We used size-structured Lefkovitch projection matrix analysis to predict future trends in the survival of Aquilaria crassna (Thymelaeaceae), a tropical evergreen forest tree that has been highly sought after for its valuable aromatic wood (agarwood) for millennia. Data on growth, damage to trees by poachers, fruit production, seed dispersal and seedling recruitment were collected from a 30-ha plot in Khao Yai National Park, central Thailand that had seen moderate poaching. The population asymptotic growth rate, λa, and transient growth rate, λtr, found from using the matrix to project the observed population 48 years, were 1.002 and 1.005, respectively, with 95% confidence intervals of [0.985, 1.016] and [0.985, 1.023]. The stable size distribution obtained from the matrix was reasonably similar to the observed size distribution, suggesting that at the time of the study the population was not far from equilibrium. Sensitivity analysis and simulations of poaching on adult trees indicate that both λ’s are very sensitive to the removal of adult trees and the growth of preadult trees. In particular, the increase in tree mortality and decrease in preadult growth rate caused by agarwood collection seen in some areas could cause extirpation of the population. While in such cases the population appears to be poised on the brink of decline, several factors that we could not evaluate could alter its fate. First, adult deaths could stimulate recruitment of young under the parent trees; second, there is marked year-to-year variation in fruiting success and possibly recruitment; third, there is considerable spatial variation in tree density and recruitment, suggesting that attempts to evaluate future success need to encompass larger spatial and time scales.  相似文献   

14.
The variation of the morphological characters of bitter and sweet African bush mango trees (Irvingia species) was investigated in the Dahomey Gap which is the West African savannah woodland area separating the Upper and the Lower Guinean rain forest blocks. African bush mangoes have been rated as the highest priority multi-purpose food trees species that need improvement research in West and Central Africa. A total of 128 trees from seven populations were characterized for their bark, fruits, mesocarp and seeds to assess the morphological differences between bitter and sweet trees and among populations. Multivariate analysis revealed that none of the variables: type of bark, mature fruit exocarp colour, fruit roughness and fresh mesocarp colour, could consistently distinguish bitter from sweet trees in the field. The analysis of the measurements of fruits, mesocarps and seeds demonstrated that bitter fruits have the heaviest seeds and this consistently distinguishes them from sweet fruits. However, the measurements of the fruit, mesocarp and seed did not have a joint effect in grouping types and populations of ABMTs. This indicates high diversity with a potential for selection existing across all phytogeographical regions investigated. The sweet trees of Couffo and those of Dassa in Benin are clearly different from all other populations. This can be attributed to traditional domestication (bringing into cultivation) and climate, respectively. The large fruits and the heavy seeds of the cultivated populations are evidence of successful on-going traditional selection of sweet trees in the Dahomey Gap.  相似文献   

15.
Forest restoration programmes aim to use material for re-planting that is genetically diverse and not inbred. However, restricted seed sampling, high variance in reproductive output, and the production of inbred seeds that survive in the nursery but not in the wild can lead to forest restoration stock being genetically compromised. The aim of this study was to evaluate whether the reproductive biology of the New Caledonian endemic conifer Araucaria nemorosa makes it susceptible to these genetic problems and to assess whether there is evidence for genetic bottlenecks and elevated inbreeding in nursery stock compared to seedlings and adults from wild source populations. Reproductive output was low with high variance among trees (only 14% of adult trees surveyed produced mature cones, >50% of examined cones had <10 viable seeds). Evidence for an extreme genetic bottleneck was detected in a nursery population established from cones collected from adult trees. A second nursery population established with seed collected from the forest floor showed no evidence of a genetic bottleneck, but was inbred compared to its wild source population. In light of these results, we do not recommend collecting cones directly from A. nemorosa as an efficient means of establishing genetically diverse stock for restoration programmes. Collecting seed from the forest floor is likely to be more effective, but the planting stock may contain a high proportion of inbred individuals. Collecting established wild seedlings already subjected to natural selection is suggested as an alternative method of maximising the diversity captured, whilst minimising sampling effort and proportion of inbred individuals.  相似文献   

16.
Ant-dispersed plants are often conspicuously rare in young forests and near forest edges. We monitored the distributions of five ant-dispersed plant taxa, the seed-collecting ant community, and variation in seed predation pressure by rodents in a 350-acre mesic forest in northern New York, USA to assess the incidence and effect of plant-animal interactions within the context of landscape history and proximity to forest edges. Sample plots were located in young and older forest stands (distinguished based on an 1880 map for forest cover) at varying distances from the forest edge. All five plant taxa were rarer in plots near forest edges, although diversity was more strongly influenced by landscape history. A sixth herbaceous species, one dispersed by vertebrates, was not influenced by forest edge proximity. The most effective seed-collecting ant, Aphaenogaster rudis, was less common in forest edge plots relative to interior plots, and predation pressure by small mammals was almost twice as great in plots near forest edges. Exclusion experiments demonstrated that ants (mutualists) and rodents (seed predators) compete for access to seeds, that ants can provide seeds some protection from mammal predation in most plots, and that the density of ant-dispersed plants is correlated with the proportion of rodent-accessible seeds that are collected by Aphaenogaster. Greater predation pressure and a paucity of ant mutualists may contribute to the rarity of ant-dispersed plants in edge habitats relative to forest interiors.  相似文献   

17.
Secondary forests and exotic tree plantations are rapidly expanding across tropical landscapes, yet we currently have a very poor understanding of the value of these human-dominated forest landscapes for biodiversity conservation. Mist netting, point counts and transect walks were used to compare the bird communities of these habitats and neighboring primary forest in north-east Brazilian Amazonia. The extensive spatial scale of plantations and second-growth in our study area enabled us to implement a robust replicated design, with survey plots approximately two to three orders of magnitude larger than most previous studies of land-use change in the tropics, thus minimising the influence of the surrounding landscape. Species richness was highest in primary forest and lowest in Eucalyptus plantations, and community turnover between habitats was very high whether based upon matrices of relative abundance or species presence-absence data, and for both point count and mist net data. Monthly line-transect censuses conducted over an annual cycle showed an increase in the detection of canopy frugivores and seed predators during the peak of flower and fruit availability in primary forest, but failed to suggest that second-growth or Eucalyptus stands provide suitable foraging habitat at any time of the year. The conservation value of both secondary forest and plantations was low compared to conclusions from previous studies. Our results indicate that while large-scale reforestation of degraded land can increase regional levels of diversity, it is unlikely to conserve most primary forest species, such as understorey insectivores and canopy frugivores.  相似文献   

18.
Globally, bird numbers are declining, with potentially serious flow-on effects on ecosystem processes, such as seed dispersal mutualisms. However, management to maintain seed dispersal may be inappropriate if unexpected animals are the most important dispersers. Numbers of the world’s only alpine parrot, the New Zealand kea (Nestor notabilis), have declined drastically over the last 120 years after an intense period of official persecution. Today <5000 kea remain in the wild. Previously it has been assumed that like other parrots, kea would destroy most of the seeds they eat, thereby contributing little to seed dispersal. The New Zealand alpine flora is rich in fleshy-fruited species yet has a limited disperser fauna. Consequently, we investigated the relevance of kea as a seed disperser in New Zealand’s alpine ecosystems. Field-based foraging observations coupled with faecal analyses showed kea were by far the most important extant alpine avian frugivore. Kea selected more fruiting species (21 vs. 17 species), consumed more fruit, and dispersed more seeds (8137 vs. 795) than all other birds combined. Rates of seed predation by kea were extremely low, and evident in only 25% of species eaten. Kea are the only species that make frequent long-distance flights within and between mountain ranges. Hence, much of the effective long-distance dispersal of the alpine flora may be currently performed by kea. Conservation of kea is therefore important both for ensuring the survival of the species and for their role in seed-dispersal mutualisms for which there are few extant substitutes.  相似文献   

19.
The responses of plant-animal interactions to forest fragmentation can vary. We hypothesized that large-seeded plant species would be more susceptible to forest fragmentation than small-seeded species because large-seeded species rely on a few, extinction prone dispersers. We compared seed dispersal of the large-seeded, mammal dispersed Duckeodendron cestroides and the small-seeded, avian dispersed Bocageopsis multiflora. The number, percentage, distance, and distributions of dispersed seeds were all reduced in fragments for Duckeodendron but not for Bocageopsis. Other fragmentation research in tropical communities supports this hypothesis through three lines of evidence: (1) Large-seeded plant species are more prone to extinction, (2) Fragmentation restricts or alters the movement of large animal dispersers more than small dispersers, and (3) Large and small-seeded species seem to be differentially linked to primary and secondary forest habitats. Therefore, small-seeded plants may be more resilient to forest fragmentation while large-seeded species may be more susceptible and should be a priority for conservation.  相似文献   

20.
The location of roosts of two species of vespertilionid bats, the lesser long-eared bat (Nyctophilus geoffroyi) and Gould’s wattled bat (Chalinolobus gouldii), was investigated in a remnant vegetation-farmland mosaic and adjacent floodplain forest in south-eastern Australia. A total of 45 individuals of N. geoffroyi and 27 C. gouldii were fitted with radio transmitters, which resulted in the location of 139 and 89 roosts respectively. Selection of roosting habitat showed both inter- and intra-specific differences. At the landscape level, locations of roosts used by male and female N. geoffroyi differed markedly. Most males roosted in the farmland mosaic within 3 km (mean 1.9±2.9 km) of where they were captured while foraging in remnant vegetation. In contrast, roost sites of females were predominantly in the floodplain forest, 6-12 km from their capture site in farmland (mean for all females, 6.7±2.9 km). All maternity roosts were in the extensive floodplain forest, 4-10 km from foraging areas. Distances moved by this species were greater than previously recorded and further than predicted by flight morphology. Most C. gouldii roosted in the floodplain forest, 4-10 km from their capture site (6.9±1.6 km). Within the floodplain forest, both species roosted in areas that had higher densities of hollow-bearing trees than generally available; dead hollow-bearing trees for N. geoffroyi and large, live trees for C. gouldii. The scale of movements undertaken by these species means that they can obtain resources from multiple landscape elements. Both species used different habitats for roosting and foraging despite the energetic costs of commuting relatively large distances. Conservation of bat populations in rural environments needs to be considered at the landscape scale, with particular attention to identifying landscape elements that provide key resources.  相似文献   

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