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1.
The interactions among plants and pollinators are crucial for plant reproduction because they structure gene flow among individual plants and among populations of plants. Throughout the Neotropics there has been a strong increase in recent years in the use of artificial nectar feeders in private nature reserves to encourage ecotourism through prolonged observations of hummingbirds. Currently, there is considerable uncertainty whether artificial feeders have a detrimental effect on plant reproduction through competition or a beneficial effect through facilitation. This uncertainty is disconcerting given that nature reserves harbour many rare and endangered plants whose successful reproduction is a conservation goal. To assess whether nectar feeders affected hummingbird visitation to flowering plants, we determined visitation rates in ten flowering species in five Andean nature reserves in Ecuador. We found that visitation rates tended to be higher within 5 m around the feeders than they were at 100 m, 500 m, or 1.5 km distance to the feeders, therefore indicating that nectar feeders tended to facilitate flower visitation at close distance. Because visitation rates at 100 m and 500 m distance from the feeders did not differ from those at 1.5 km, we suggest that feeders do not draw hummingbirds away from flower resources, but if they have an effect on flower visitation at all, they tend to facilitate flower visitation rather than reduce plant reproduction.  相似文献   

2.
《农业工程》2014,34(3):135-140
Habitat suitability assessment is an essential and dynamic research method for determining and evaluating the environmental pressures faced by wildlife. From March to November 2011, we investigated the quality of habitat available to Sichuan sika deer (Cervus nippon sichuanicus) in Tiebu Nature Reserve, Ruoergai County, Sichuan Province, China. A habitat evaluation model established by the fuzzy assignment quadrature method was used to assess habitat suitability for Sichuan sika deer within the reserve by using the GIS spatial analysis function. The results showed that the area of actual available habitat was 220.8 km2 during the wet season and 213.2 km2 during the dry season, accounting for 80.8% and 78.02% of the total nature reserve area, respectively. The area of suitable habitat for Sichuan sika deer was much lower, 128.01 km2 during the wet season and 109.17 km2 during the dry season, accounting for 46.84% and 39.95% of the total nature reserve area respectively. The difference between available and suitable habitat is likely due to potentially good habitat having been lost as a result of human disturbance. Lost habitat makes up 4.55% of the total area while grass is green and 5.52% while grass is dry. Human disturbance levels in the form of roads and residential areas were constant throughout the year, but grazing by domestic animals had a higher impact during the dry season. Habitat suitability during this time, already reduced by the withering of the grass, was thus further reduced by the grazing of livestock.  相似文献   

3.
Roads have many effects on the mammal populations of their surroundings. Prey species are thought to establish dense populations in road verges due to a predation release effect, which arise as a side-effect of roadside avoidance by predators and/or predator roadkill. A species that has been suggested to benefit from predation release and attain high densities near roads is the European rabbit, a keystone species in Mediterranean ecosystems. We monitored rabbit relative abundance at three distances from a motorway (50, 450 and 850 m) during a 6 month period, as well as hunting and predator pressures, in a suitable area for rabbits. The lowest rabbit abundance was found next to the motorway (6.76 ± 8.87 pellets/m2 per month) and the highest abundance at an intermediate distance (17.65 ± 23.11 pellets/m2 per month). Hunting and carnivore pressures were highest at the sampling transect located farthest from the infrastructure. Thus, variability in rabbit abundance did not match the predation release effect found close to the motorway, and some sort of road avoidance or other process must underlie the observed abundance pattern. We advocate for a formal measurement of prey populations response to roads prior to any generalization as, in the case of rabbit, the response to roads and the potential cascading effects on other species may depend on landscape characteristics.  相似文献   

4.
Roads and road-building are among the most important environmental impacts on forests near urban areas, but their effects on ecosystem processes and species distributions remain poorly known. Termites are the primary decomposer organisms in tropical forests and their spatial distribution is strongly affected by vegetation and soil structure. We studied the impacts of road construction on termite community structure in an Amazonian forest fragment near Manaus, Brazil. One leading question was whether the fragment under study was large enough to maintain the termite species pool present in nearby continuous forests. We also asked how soil moisture and canopy openness varied with proximity to roads, and whether these changes were associated with changes in termite species richness and composition in the fragment. While the forest fragment had a termite composition very similar to that of continuous forests, roads caused important changes in soil moisture and canopy openness, especially when close to forest edges. At distances of up to 81 m from roads, changes in soil moisture were significantly related to changes in termite species composition, but there was no correlation between canopy openness and species richness or composition. These results suggest that fragmentation caused by roads impacts termites in a different and less damaging manner than fragmentation caused by other kinds of degradation, and that even fragments bisected by roads can support very diverse communities and even undescribed taxa of termites. We conclude that a buffer zone should be established for conservation purposes in the reserves surrounded by roads.  相似文献   

5.
The Pendjari Biosphere Reserve located in the Sudanian zone of Bénin, is a protected area well managed, but mainly aimed at wild animal conservation. This study assessed its effectiveness to conserve habitat species composition and population structure of three endangered African tree species: Afzelia africana Sm., Pterocarpus erinaceus Poir. and Khaya senegalensis (Desv.) A. Juss. We randomly sampled 120 plots in the protected and surrounding unprotected habitats by inventorying plant species. For the three target species, we estimated adult and juvenile densities and recorded size classes. According to floristic composition four habitats groups were recognized in relation to human disturbance, vegetation type, and moisture. These were protected savannas, unprotected savannas, old fallows and gallery forests. The estimated adult densities of A. africana were similar between protected (14 ± 1.2 tree/ha) and unprotected savannas (17 ± 0.9 tree/ha) while for P. erinaceus the adult density was significantly higher in protected (12 ± 3.7 tree/ha) than in unprotected savannas (5 ± 1.9 tree/ha). Estimated adult density of K. senegalensis was also significantly higher in protected gallery forest (40 ± 5.8 tree/ha) than in unprotected one (29 ± 4.8 tree/ha). Juvenile densities of A. africana, K. senegalensis and P. erinaceus were higher in protected habitats than in unprotected ones but the difference was not significant. Skewness coefficient indicated that populations of investigated trees were declining in their protected habitats. However, in the case of A. africana and K. senegalensis populations seemed to be mostly threatened in the protected area. We concluded that although the studied protected area is effective to conserve some habitats species compositions, protection is not sufficient to guarantee future conservation of some threatened tree species.  相似文献   

6.
Spatial information at the landscape scale is extremely important for conservation planning, especially in the case of long-ranging vertebrates. The biodiversity-rich Anamalai hill ranges in the Western Ghats of southern India hold a viable population for the long-term conservation of the Asian elephant. Through rapid but extensive field surveys we mapped elephant habitat, corridors, vegetation and land-use patterns, estimated the elephant population density and structure, and assessed elephant–human conflict across this landscape. GIS and remote sensing analyses indicate that elephants are distributed among three blocks over a total area of about 4600 km2. Approximately 92% remains contiguous because of four corridors; however, under 4000 km2 of this area may be effectively used by elephants. Nine landscape elements were identified, including five natural vegetation types, of which tropical moist deciduous forest is dominant. Population density assessed through the dung count method using line transects covering 275 km of walk across the effective elephant habitat of the landscape yielded a mean density of 1.1 (95% CI = 0.99–1.2) elephant/km2. Population structure from direct sighting of elephants showed that adult male elephants constitute just 2.9% and adult females 42.3% of the population with the rest being sub-adults (27.4%), juveniles (16%) and calves (11.4%). Sex ratios show an increasing skew toward females from juvenile (1:1.8) to sub-adult (1:2.4) and adult (1:14.7) indicating higher mortality of sub-adult and adult males that is most likely due to historical poaching for ivory. A rapid questionnaire survey and secondary data on elephant–human conflict from forest department records reveals that villages in and around the forest divisions on the eastern side of landscape experience higher levels of elephant–human conflict than those on the western side; this seems to relate to a greater degree of habitat fragmentation and percentage farmers cultivating annual crops in the east. We provide several recommendations that could help maintain population viability and reduce elephant–human conflict of the Anamalai elephant landscape.  相似文献   

7.
This study examines the relation between primary forest loss and landscape characteristics in the Ucayali region, Peru. Seven variables (rivers, elevation, annual precipitation, soil suitability for agriculture, population density, paved roads, and unpaved roads), were identified as potential deforestation drivers. The variables were converted into spatially explicit layers of continuous data and divided into a 9 km2 grid. A multiple regression analysis was conducted to determine variable significance. Distance to paved and unpaved roads were strongly associated with deforestation, followed by distance to rivers, annual precipitation and elevation. All significant variables were negatively correlated with deforestation. Variables excluded from the model were population density and soil suitability for agriculture, suggesting that the influence of population density on forest clearing across the study area was not significant, and that deforestation activities were undertaken regardless whether soils are suitable for agriculture or not. Based on the linear regression analysis, the significant variables were selected and added to the Land Change Modeler in order to project primary forest coverage by 2025. The modeling results predict extensive deforestation along the Aguaytia River and at the forest/non-forest interface along the paved highway. The rate of primary forest removal is expected to increase from 4783 ha y−1 (for the 2007–2014 period) to 5086 ha y−1 (for the 2015–2025 period). A preliminary survey questionnaire conducted to explore deforestation intentions by farmers in the region, partly confirmed the overall deforestation trends as projected by the model.  相似文献   

8.
As time and money is limited, explicit, cost-effective, quick, and appropriate methods are needed to assist conservation planners and managers for making quick decisions. Butterflies promise to be a good model for rapid assessment and habitat monitoring studies because they are widespread, conspicuous, and easily recognizable and they are effective indicators of forest health. We conducted a rapid assessment of butterflies at five disturbance gradient sites that varied in elevation from 900 m a.s.l. to 3500 m a.s.l. for 20 days during March–April 2010 and recorded 79 butterfly species and 1504 individuals in the Tons valley in Western Himalayas. We were able to sample approximately 77% (123 species) of the estimated species richness on continuing the sampling until July 2010. Species richness at the study site is estimated to be 159 (95% CI: 145–210) species. Diversity was highest in heterogeneous habitats and decreased towards homogeneous habitats. Unique species were highly restricted to lowest disturbed sites. Using Pearson's correlation analysis, the strongest vegetative predictors of butterfly richness were plant species richness, canopy cover, and herb and shrub density. Butterfly species richness and abundance were highly correlated with altitude, temperature, relative humidity, fire signs, and livestock abundance. We also found positive cross-taxon correlation among butterflies, moths, and beetles across sites, indicating that butterflies can be used as surrogate or indicator taxa for insect conservation. Short sampling periods providing comprehensive estimates of species richness were reliable for identifying habitats and sites with the most conservation value in the Tons valley landscape.  相似文献   

9.
Humans can unintentionally induce both positive and negative effects on wildlife presence and abundance, with organisms living in or associated with agricultural areas being good examples. Our study focused on a 1500 ha area (75 sampled 100 m × 50 m plots) at the driest edge of the endemic Iberian mole Talpa occidentalis distribution range, where the species is listed as “Vulnerable”. Here, poplar cultivations dominate wasteland and other irrigated and non-irrigated crops. The poplar irrigation system was traditionally based on a network of straight ridges, although it is rapidly being replaced with a sophisticated procedure which permits water to spread with ridges no longer being needed. In these habitats, ridges are relevant for moles because they provide dry shelters for nests. In this paper we explore (a) mole local habitat preferences and (b) the impact of changes in poplar irrigation systems on mole abundance. Iberian mole abundance positively related to earthworm biomass and numbers; however, multivariate analyses highlighted the effect of herbaceous cover (positive relationship), rocks cover and soil hardness (negative relationship), and habitat type (poplar being the preferred one). Furthermore, mole abundance was substantially higher in poplar groves where ridges were still present than where they were not. We conclude that Iberian moles in semi-arid environments are favoured by poplar plantations but, at the same time, they are highly vulnerable to recent changes in traditional agriculture practices. Therefore, this study shows how agricultural habitats can benefit some species of conservation concern, especially some temperate species at the edge of their range or in extreme ecological conditions. Changes in agricultural practices that negatively affect the suitability of such habitats can compromise these species's conservation, as we found for the Iberian mole.  相似文献   

10.
We contrasted traditionally used indicators of service provision quality, such as overall species richness and growth form composition, to three more specific functional properties: functional diversity, functional intensity, and functional stability. We defined flower colour as a functional trait perceived differently by humans and insect pollinators, and used user specific colour richness, flower size, and species richness within colour group as indicators of these three properties. We asked (1) do field margins and road verges provide flower-based ecosystem services with the quality of permanent grasslands; and (2) do traditional and detailed functional indicators of service provision quality agree on the service quality ranking of habitats?In an agricultural landscape of central and south-eastern Estonia (115 ÿ 95 km area, centroid 26°49⿲43⿳ and 58°54⿲49⿳) we sampled 87 field margins and 111 road verges as linear grassland-substitution habitats, and 84 permanent grasslands to scale their service quality.Linear habitats generally provided service of lower quality than permanent grasslands, but detailed indicators showed less evident contrast among habitat types than the overall species richness and stronger contrast than the proportion of forbs. Detailed indices, however, had strong seasonal dynamics to take into account. Vegetation in the first year field margins had greater colour richness (functional diversity) and species richness within colour groups (functional stability), but the smallest flower size (functional intensity), in contrast to road verges. By the third year of succession, field margins had become more similar to road verges. Indication of service provision quality differed between humans and pollinators, but their estimates were correlated across habitats.We showed that (1) combinations of specific service quality indicators provide more adequate information than generalized richness or growth form system, and (2) single grassland surrogate habitat type is an insufficient service providing substitute for permanent grasslands, although a mosaic of these habitats might be more efficient. Therefore, remnant fragments of semi-natural grasslands should receive top priority attention for conservation and restoration, particularly in agriculture dominated landscapes.  相似文献   

11.
Lichen bioindication can provide economical and spatially extensive monitoring of climate and pollution impacts on ecological communities. We used non-metric multidimensional scaling of lichen community composition and generalized additive models to analyze regional climate and pollution gradients in the northern Rocky Mountains, U.S. Temperature extremes, relative humidity, and N-deposition were strongly related to lichen community composition. Eutrophic species (genera Physcia, Xanthomendoza, and Xanthoria) were associated with high N deposition, low precipitation, and temperature extremes. Estimated N deposition in our study ranged from <0.5 to 4.26 kg N ha−1 year−1 with degradation to lichen communities observed at 4.0 kg N ha−1 year−1, the indicated critical load. The resulting model can track changes in climate and N pollution related to lichen communities over time, identify probable sensitive or impacted habitats, and provide key information for natural resource management and conservation. The approach is broadly applicable to temperate ecosystems worldwide.  相似文献   

12.
In this study, we analysed the variability of reserve storage in juvenile European hake (Merluccius merluccius) off the western coasts of Italy (Central Mediterranean Sea). Reserve storage was measured by the hepatosomatic index (HSI), in relation to environmental and population covariates. HSI has been proved to be a consistent measure of energy storage in gadoids, thus reflecting quantity and quality of food availability for growth. Generalized Additive Models for Location, Scale and Shape (GAMLSS) were used to model the effect of depth, bottom temperature, bottom currents, fish density and fish body size on HSI of juvenile European hake. The results revealed that reserve storage in the liver appears to be maximized for juveniles living on the shelf break, between 120 and 170 m depth, with bottom temperature and current speed not exceeding 14 °C and 0.04 m s−1 respectively. Furthermore, HSI significantly increased with fish density up to about 6000 individuals per km−2 and decreased at higher densities indicating that reserve accumulation in the liver might be subject to density-dependent mechanisms (e.g. competition for food) as well. These findings suggest that the use of density as measure of nursery importance need to be further investigated. Finally, we found that HSI increased with fish size up to about 14 cm total length. Based on these results, HSI appears a reasonable index to indirectly measure the quality of habitats where juvenile European hake aggregate after their settlement on the bottom, and to potentially monitor habitat suitability as nursery across the spatial-temporal gradient.  相似文献   

13.
Changes in the woodland extent over the last 200 years were assessed from old maps for a 100 ha woodland nature reserve in southern Britain. More detailed changes in the composition and structure of the tree and shrub layers were measured using data from 95 permanent vegetation plots (10 × 10 m) distributed across the reserve at the intersections of a 100 m grid. These were recorded in 1973, 1992 and 2009. The woodland area has more than doubled since the 18th century, but whereas the pre-1800 woodland was mainly Fagus sylvatica the more recent woodland was initially predominantly conifer plantation. These plantations have since developed into mainly broadleaved high forest of Fraxinus excelsior and Acer pseudoplatanus. Changes on the site are the combination of active interventions through management and natural processes (differential species growth, death from disease, windthrow, herbivore damage). Further changes are likely in future in particular from ash dieback (Hymenoscyphus fraxineus) and climate change impacts. Many of the changes seen on this reserve are mirrored in woods elsewhere in Britain and Europe. Over periods of a few decades and at the whole-reserve scale the woods can be considered to be relatively stable; at the plot level, or over time-scales of centuries they are very dynamic. Whether woods are judged to be resilient must include definition of the temporal and spatial scales.  相似文献   

14.
Current research includes the effects of asphalt forest roads on changes of plant cover and tree regeneration from asphalt forest roads edges towards its inner parts in two compartments of Nave Asalem forests located in the north of Iran. For this reason, in each side of road, 6 sample plots (20 m × 20 m) were established for measuring plant species diversity. In each sample plot, ground vegetation and tree regeneration were assessed within nine 2 × 2 m micro plots. In total, 12 sample plots and 108 μ plots were established. Results indicated that the road positions were effective on plant species diversity. The highest diversity and evenness indices value were observed down of the road compared to the up of the road position for herbal and tree regeneration layers. The same results were found also for herbal richness indices. Up of road position had the greatest value of richness indices in comparison to the other road position for tree regeneration layer. Also, the results showed that diversity, richness, and evenness indices were decreased with the increasing of distance from the road side for herbs and tree regeneration layers. This study indicated that roads can increase plant biodiversity; that is, tree regeneration density.  相似文献   

15.
Marine protected areas (MPAs) are considered as a tool for marine conservation and sustainable fishery resource management. Improvements in fishery yields should take place via the spill-over of individuals from the reserve. In general, it has been demonstrated that MPAs affect the density and biomass of the organisms within them, however, little evidence has been found in order to assess the exportation of individuals across their boundaries. In this study, a simple model involving population growth, harvest, and the diffusion coefficient for individuals was used to explore the effects of protection on populations inside the reserve and the spill-over of individuals to the fished area. The model showed that biological responses inside marine reserves appear to develop quickly, reaching mean levels within a short (1–5 year) time period. Mean population abundance is always higher inside the reserve and highlights the effectiveness of protection, particularly when there is strong fishing pressure outside the reserve. However, reserves smaller than 2000 m radius show significantly lower levels of abundance inside than larger sites. Large MPAs (i.e. about 2000 m in radius) offer nearly the maximum capacity for recovery (close to 100% of the system carrying capacity) and nearly the maximum flux of individuals per unit boundary length. Very large MPAs (i.e. larger than 6000 m in radius) could be a guaranteed means of providing resilience in order to prevent population crises, with the added advantage that the flux of individuals is slightly higher at larger distances from the boundary. However, in practice they provide no further advantage towards increasing the density of individuals or the exportation of biomass, and a network of smaller MPAs could be more beneficial, both from the point of view of conservation and of benefits to fisheries.  相似文献   

16.
We used 474 European plant species to analyse the impacts of climate and land-use change on the composition of habitat-specific species pools in Germany. We quantified changes in the probability of occurrence of species in a grid cell using an ensemble of three statistical modelling techniques, namely generalized linear models (GLMs), generalized additive models (GAMs) and random forests (RFs), under three scenarios (average change +2.2, +2.9, and +3.8 °C up to 2080). We evaluated the impact on single species occurrence and resulting species pools considering their affiliation to ten major terrestrial habitat types in both current (1961–90) and future projections (2051–80). Current habitat-specific species pools declined in size across all scenarios, e.g. by 24 ± 13% (mean ± s.d.) under the most severe scenario. We show that species responses may strongly vary among scenarios and different habitats with a minimum average projected range loss of 14% (±18%; species typical to urban habitats under moderate climate change assumptions, average temperature increase +2.2 °C) to a maximum average projected range loss of 56% (±29%; species assemblages from mountain communities below the alpine zone at +3.8 °C). A separate analysis of species composition in habitat-specific species pools revealed a significant interaction between the scenario and the major habitat classes. We found a higher risk for habitat types with high conservation value characterised by a significant association between number of nationally endangered species and projected range loss in major habitats. Thus, habitat-specific management and application of measures favouring dispersal are required for mitigation of climate change impacts.  相似文献   

17.
《Acta Oecologica》2006,29(1):9-15
Broad-scale correlations between species richness and human population suggest that processes driving species richness, mainly related to high ecological productivity, may also drive human populations. However, it is still under debate if this coincidence implies conflicts between biodiversity conservation and human development. In this paper, we analyzed the relationships among human population size, species richness and irreplaceability in Brazilian Cerrado. We analyzed a dataset with 131 species of anurans distributed in 181 cells with 1° of spatial resolution covering the biome. We found a positive correlation between human population size and anuran species richness (r = 0.46; P = 0.033 with 19.5 geographically effective degrees of freedom, v*), but the irreplaceability of each cell was poorly correlated with human population size (r = 0.075; P = 0.323; v* = 173.9). The 17 cells in the 97 optimal reserve networks contained a total human population ranging from 2942,195 to 4319,845 people, representing on average 11.8% of the human population in the entire Cerrado grid. The comparison of these observed values with 10,000 values from randomly generated networks suggests a relatively high flexibility in optimal complementarity sets for reserve selection. Our results indicated that correlation between richness and human population does not necessarily result in conflicts, given the opportunities for conciliating conservation and development. However, the analyses performed here are initial explorations within the framework of conservation biogeography, so more detailed studies are necessary to establish conservation planning at regional and local scales.  相似文献   

18.
《Aquatic Botany》2007,86(1):69-75
To obtain accurate estimates of population structure for purposes of conservation planning for wild lotus (Nelumbo nucifera Gaertn.) in central China, genetic diversity among and within six populations, and clonal diversity within another two populations of the species were analyzed. The genetic diversity was high (percentage of polymorphic bands, PPB = 90.0%; Shannon's information index, I = 0.383 ± 0.234) at the species level, but low within individual study populations (PPB = 35.8%; Shannon's information index I = 0.165 ± 0.241). The mean coefficient of gene differentiation (Gst) was 0.570, indicating that 43.0% of the genetic diversity resided within the population. Analysis of molecular variance (AMOVA) indicated that 50.47% of the genetic diversity among the study populations was attributed to geographical location while 12.3% was attributed to differences in their habitats. An overall value of mean estimated number of gene flow (Nm = 0.377) indicated that there was limited gene flow among the sampled populations. The level of clonal diversity found within the populations was considerably high (Simpson's diversity index, D = 0.985) indicating that clonal diversity contributes to a major extent to the overall genetic variation in the genetic structure of N. nucifera. On the basis of the high Gst and D values detected in this study we recommend that any future conservation plans for this species should be specifically designed to include those representative populations with the highest genetic variation for both in situ conservation and germplasm collection expeditions.  相似文献   

19.
River valleys have been subjected to human-induced changes for centuries, but they are still considered regional hotspots of biodiversity. In central Europe, some vascular plant species demonstrate confinement to the corridors of large rivers. They are termed river corridor plants (RCPs). RCPs are an important component of regional biodiversity and include a high proportion of threatened species, thus they deserve attention. Here we examine: (1) the detailed distribution pattern of RCPs within a river valley, (2) the habitat preferences of RCP species, and (3) the correlation between the richness of RCP species and selected variables. The studied variables include: river bed proximity, distance from the river mouth, floodplain coverage, richness of native, red listed and invasive species, and number of habitats considered to be of Europaean Community importance. Surveys were conducted in 10 transects running perpendicularly to the San River bed (Poland, central Europe). Each transect was divided into 14 plots (1 km × 1 km). In each plot, the site locations of RCPs as well as their habitats were recorded. The occurrence of all vascular plant species in a particular plot was also noted. The richness and abundance of RCP species depended on the distance from the river and the floodplain coverage in a plot. The plots located in the vicinity of the river were the richest in RCP species and usually harbored the largest number of native, red-listed and invasive species. They were also characterized by the largest number of habitats considered to be of importance to the European Community. RCP species differed in the degree of confinement to habitats regarded as typical for them. Some of the RCP species were recorded only within typical habitats while others were found in several different types of habitats, including anthropogenic ones. Knowledge concerning the RCP distribution pattern and its correlates can make restoration initiatives in river valleys more effective. While implementing conservation measures in river valleys, one should keep in mind that: (1) hotspots of RCP and invasive species spatially overlap and (2) anthropogenic linear elements occurring within river valleys constitute important habitats for some RCP species.  相似文献   

20.
Protected areas are the basis of modern conservation systems, but current climate change causes gaps between protected areas and the species distribution ranges. To mitigate the impact of climate change on species distribution ranges, revision of protected areas are necessary. Alternatively, active management such as excluding competitive species or transplanting target species would be effective. In this study, we assessed optimal actions (revision of protected areas or active management) in each geographical region to establish an effective spatial conservation plan in Japan. Gaps between the protected areas and future potential habitats were assessed using species distribution models and 20 future climate simulations. Fagus crenata, an endemic and dominant species in Japan, was used as a target species. Potential habitats within the protected areas were predicted to decrease from 22,122 km2 at present to 12,309 km2 under future climate conditions. Sustainable potential habitats (consistent potential habitats both at present and in future) without the protected areas extended to 13,208 km2, and were mainly found in northeast Japan. These results suggest that, in northeast Japan, revisions to protected areas would be effective in preserving sustainable potential habitats under future climate change. However, the potential habitats of southwestern Japan, in which populations were genetically different from northeastern populations, were predicted to virtually disappear both within and outside of protected areas. Active management is thus necessary in southwestern Japan to ensure intraspecific genetic diversity under future climate change.  相似文献   

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