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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   

3.
The identification of shape and size of sampling units that maximises the number of plant species recorded in multiscale sampling designs has major implications in conservation planning and monitoring actions. In this paper we tested the effect of three sampling shapes (rectangles, squared, and randomly shaped sampling units) on the number of recorded species. We used a large dataset derived from the network of protected areas in the Siena Province, Italy. This dataset is composed of plant species occurrence data recorded from 604 plots (10 m × 10 m), each divided in a grid of 16 contiguous subplot units (2.5 m × 2.5 m). Moreover, we evaluated the effect of plot orientation along the main environmental gradient, to examine how the selection of plot orientation (when elongated plots are used) influences the number of species collected. In total, 1041 plant species were recorded from the study plots. A significantly higher species richness was recorded by the random arrangement of 4 subplots within each plot in comparison to the ‘rectangle’ and ‘square’ shapes. Although the rectangular shape captured a significant larger number of species than squared ones, plot orientation along the main environmental gradient did not show a systematic effect on the number of recorded species. We concluded that the choice of whether or not using elongated (rectangular) versus squared plots should dependent upon the objectives of the specific survey with squared plots being more suitable for assessing species composition of more homogeneous vegetation units and rectangular plots being more suited for recording more species in the pooled sample of a large area.  相似文献   

4.
Species-based ecological indices, such as Ellenberg indicators, reflect plant habitat preferences and can be used to describe local environment conditions. One disadvantage of using vegetation data as a substitute for environmental data is the fact that extensive floristic sampling can usually only be carried out at a plot scale within limited geographical areas. Remotely sensed data have the potential to provide information on fine-scale vegetation properties over large areas. In the present study, we examine whether airborne hyperspectral remote sensing can be used to predict Ellenberg nutrient (N) and moisture (M) values in plots in dry grazed grasslands within a local agricultural landscape in southern Sweden. We compare the prediction accuracy of three categories of model: (I) models based on predefined vegetation indices (VIs), (II) models based on waveband-selected VIs, and (III) models based on the full set of hyperspectral wavebands. We also identify the optimal combination of wavebands for the prediction of Ellenberg values. The floristic composition of 104 (4 m × 4 m grassland) plots on the Baltic island of Öland was surveyed in the field, and the vascular plant species recorded in the plots were assigned Ellenberg indicator values for N and M. A community-weighted mean value was calculated for N (mN) and M (mM) within each plot. Hyperspectral data were extracted from an 8 m × 8 m pixel window centred on each plot. The relationship between field-observed and predicted mean Ellenberg values was significant for all three categories of prediction models. The performance of the category II and III models was comparable, and they gave lower prediction errors and higher R2 values than the category I models for both mN and mM. Visible and near-infrared wavebands were important for the prediction of both mN and mM, and shortwave infrared wavebands were also important for the prediction of mM. We conclude that airborne hyperspectral remote sensing can detect spectral differences in vegetation between grassland plots characterised by different mean Ellenberg N and M values, and that remote sensing technology can potentially be used to survey fine-scale variation in environmental conditions within a local agricultural landscape.  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.
Agricultural land abandonment is one of the main drivers of land use change, leading to various responses of farmland ecological communities. In an effort to better understand the effect of agricultural land abandonment on passerine bird communities, we sampled 20 randomly selected sites [1 km × 1 km] in remote Greek mountains, reflecting an abandonment gradient, in terms of forest encroachment. We sampled 169 plots using the point count method of fixed distance (47 passerine species), and we investigated bird diversity and community structure turnover along the gradient. We found that grazing intensity has a beneficial effect hampering forest encroachment that follows progressively land abandonment. Habitat composition changes gradually with forests developing at the expense of open meadows and heterogeneous grasslands. Forest encroachment has a significant negative effect on bird diversity and species richness, affecting in particular typical farmland and Mediterranean shrubland species. Birds form five distinct ecological clusters after land abandonment: species mostly found in pinewoods and cavity-dwelling species; species that prefer open forests forest edges or ecotones; species that prefer shrubland or open habitats with scattered woody vegetation; Mediterranean farmland birds that prefer semi-open habitats with hedges and/or woodlots; and, generalist forest-dwelling or shrubland species. We extracted a set of 22 species to represent the above ecological communities, as a new monitoring tool for agricultural land use change and conservation. We suggest that the maintenance of rural mosaics should be included in the priorities of agricultural policy for farmland bird diversity conservation.  相似文献   

7.
The delivery of ecosystem services, such as biotic pollination is a benefit that nature provides us. Pollinators increase the quantity, quality and stability of crops for food production. Previous works show that proximity to natural habitats increases crop production through the delivery of pollination services. However, similar researches in subtropical regions is largely lacking. In this study we evaluated the role of linear forest fragments (LFFs) on the provision of biotic pollination service to soybean crops (Glycine max) and explored whether this service changes with increasing distance to LFFs in subtropical dry Chaco (Argentina). In three agricultural farms and testing two soybean varieties, we covered plots of 0.75 m2 with soybean plants and compared them with equally sized open plots. Plots were placed near (60 m) and far (600 m) from LFFs. We found that plants from the open treatment produced 32% more pods, 41% more seeds and had 42% higher yield (kg/ha) than plants from the covered plots. The difference between open and covered plots in seeds and yield did not change significantly with the distance to LFFs, but the number of pods, contrary to what we expected, was higher far from LFFs. Our findings highlight the possible impact of pollinators on soybean yield in both varieties tested here; but the proximity to LFFs was not directly related to a larger difference in production. Observed patterns are explained by edge effects and competition between soybean plants and trees near LFFs, combined with an underestimation of the distance from the natural hives to which honeybees can efficiently exploit the crops. In this subtropical region, soybean expansion is the most important driver of land cover change and this study represents a first step towards a better understanding of the functioning of these remnants of natural areas within the agricultural land in the region of dry Chaco forests.  相似文献   

8.
We examined the relationship between coastal habitats (sensu European Union Habitats Directive) and local dune morphology along a Mediterranean coastal dune system by integrating field collected vegetation data and remotely sensed imagery. Specifically, we described the morphological profile of each EC habitat based on the morphological variables that are most likely to affect their occurrence, including elevation, slope, curvature, northness, eastness and sea distance. In addition, we assessed the role and strength of each morphological variable in determining the occurrence of EC habitats.We used 394 random vegetation plots representative of six EC habitats (Habitat 1210: “Annual vegetation of drift lines”; Habitat 2110: “Embryonic shifting dunes”; Habitat 2120: “Shifting dunes along the shoreline with Ammophila arenaria”; Habitat 2210 and 2230: “Crucianellion maritimae fixed beach dunes” and “Malcolmietalia dune grasslands”; Habitat 2250: “Coastal dunes with Juniperus spp.”; Habitat 2260: “Cisto-Lavanduletalia dune sclerophyllous scrubs”) found along the Tyrrhenian coast of central Italy. We derived each morphological variable from a DTM (Digital Terrain Model) obtained from 2-m resolution LiDAR (Light Detection And Range) images. The mean value of each variable was calculated at different spatial scales using buffer areas of increasing radius (2 m, 4 m, 8 m) around each vegetation plot. Mean morphological values for each EC habitat were compared using Kruskal-Wallis rank test. The role and strength of the relationship between habitat type and the morphological variables were assessed using Generalized Linear Models.EC habitats occur differentially across dune morphology, and the role and strength of each morphological variable define habitat specificity. Dune elevation and sea distance were determined to be the key factors in shaping EC habitat occurrence along this section of the Mediterranean coast. Identification of the close relationship between habitat type and morphological variables deriving from airborne LiDAR imagery points to the high potential of such remote sensing tool for analyzing and monitoring the integrity of coastal dune ecosystems. As airborne LiDAR enables the rapid collection of extremely accurate topographic data over large areas, it also offers useful information for the management of these threatened and fragile ecosystems.  相似文献   

9.
《Ecological Engineering》2007,29(3):232-244
Urban wetlands typically have few plant species. In wetlands designed to improve water quality, nutrient-rich water and highly variable water levels often favor aggressive, flood-tolerant plants, such as Typha × glauca (hybrid cattail). At Des Plaines River Wetlands Demonstration Site (Lake Co., IL), we assessed T. × glauca dominance and plant community composition under varying hydroperiods in a complex of eight constructed wetlands. Plots flooded for more than 5 weeks during the growing season tended to be dominated by T. × glauca, while plots flooded fewer days did not. Plots with high cover of T. × glauca had low species richness (negative correlation, R2 = 0.72, p < 0.001). However, overall species richness of the wetland complex was high (94 species), indicating that wetlands in urbanizing landscapes can support many plant species where T. × glauca is not dominant. T. × glauca-dominated areas resisted the establishment of a native plant community. Removing T. × glauca and introducing native species increased diversity initially, but did not prevent re-invasion. Although 12 of the 24 species we seeded became established in our cleared plots, T. × glauca rapidly re-invaded. In year 1, T. × glauca regained an average of 11 ramets m−2, and its density doubled in year 2. The likelihood of planted species surviving decreased as duration of inundation increased, and in both seeded and planted plots, graminoids had greater survivorship through year 2 than forbs across a range of water levels. Within 4 years, however, T. × glauca was the most common plant, present in 92% of the cleared plots. Simply removing T. × glauca and adding propagules to an urban wetland is not sufficient to increase diversity.  相似文献   

10.
Invasive species of the knotweed complex (Fallopia sp.) have repeatedly been shown to decrease diversity of native local biota. While effects on plant species richness are well established, effects on invertebrate and in particular gastropod species richness are less well understood. We recorded cover of plant species and diversity and abundance of gastropod species in four plots (1 m × 1 m) with Fallopia japonica and compared these to paired control plots without F. japonica at 15 sites along the river Birs (Switzerland) in early summer (June) and autumn (September). Knotweed and control plots did not differ in site characteristics and soil parameters.Average plant species richness in F. japonica plots was 50% lower compared to control plots. This reduction was significant for woody species as well as for herbaceous species. However, species richness of early flowering annuals did not differ significantly. Among the species most affected by knotweed were hop (Humulus lupulus) and European spindle tree (Euonymus europaeus) but also stand-forming species such as nettle (Urtica dioica) or ground elder (Aegopodium podagraria).Average snail species richness was significantly reduced in F. japonica plots. The reduction was pronounced in large (≥5 mm shell size) and long-lived (>2 years) snail species but not in slugs or small and short-lived snails. For example, large snails such as the Roman snail (Helix pomatia, ?85%) or the red-listed species Bradybaena fruticum (?93%), showed reduced abundances in F. japonica compared to control plots. In contrast, the red-listed but small Vertigo pusilla (+92%) had higher abundances in F. japoinca plots. Principal component analyses revealed little overlap in plant communities or community composition of large snail species between F. japonica and control plots. Taken together, knotweed invasion decreased the cover of most plant species and abundance of large and long-lived gastropods.  相似文献   

11.
Habitat manipulations through the use of fire or mechanical treatments are often used to combat woody plant encroachment and increase foraging opportunities for wildlife and livestock. This creates spatial heterogeneity in habitat quality that large herbivores should respond to in ways predicted by ideal free distribution theory. We monitored free-ranging bison to test whether, (1) manipulated habitats offer higher quality forage than habitats in undisturbed rangeland, (2) bison respond through changes in herd composition or activity to differences in habitat quality, and (3) burned and mechanically treated habitats offer similar forage qualities. We found that habitat types burned ∼10 years ago continue to produce higher quality forage as evidenced by bison fecal N concentration (14.4 g kg−1 dry mass) than open (10.5 g kg−1), closed (10.6 g kg−1), or mechanically manipulated habitats (11.7 g kg−1). Bison herd composition and activity did not vary across habitat types within seasons, despite some between-season variation in overall group composition with sexual segregation being most evident before mid-summer. For semi-arid rangelands encroached with woody vegetation (e.g. piñon–juniper in the western USA) our evidence from free-ranging bison indicates that burning results in higher quality forage than occurs in both mechanically manipulated and undisturbed habitats. Bison roam widely from water, sample available vegetation continuously, and are long-lived gregarious animals that learn to exploit the spatiotemporal heterogeneity in their large home ranges. Bison also have very similar diets to cattle and so, where bison and cattle are allowed to comingle, we suggest the foraging parameters of free-ranging bison are effective ecological indicators of rangeland quality for both bison and cattle.  相似文献   

12.
This research represents one of the first studies in Amazonia to examine soil moisture and water-use efficiency (WUE) in secondary forest (SF) vegetation regrowing on abandoned pastures subjected to reduced nutrient constraints via a nutrient addition experiment. Extensive forested areas (about 80% of deforestation) have been converted to pastures in Amazonia, which were later abandoned following soil degradation and reduction in grass productivity. Colonization of these areas proceeds through species adapted to adverse edaphic conditions, such as low soil nutrients. Yet there is little data from such environments showing the interaction of soil nutrients and water availability on plant physiological processes. The objective of this study was to test whether three common SF tree species have positive physiological responses, e.g. increased photosynthesis and water-use efficiency, when nutrient limitations are relaxed through fertilization. The experiment was conducted on an abandoned pasture in central Amazonia with 6-year-old secondary vegetation following the application of four treatments: control; +phosphorus (P); +phosphorus and lime (P + Ca); and +phosphorus, lime and gypsum (P + Ca + G). The control had higher mean soil moisture at 140 and 180 cm depth at the end of the dry season, indicating that the treatment plots responded positively to fertilizer additions by taking up additional water. Trees of Vismia japurensis and Bellucia grossularioides growing on the fertilized plots had the highest net photosynthesis rates (A) (18.7 and 20.4 μmol m?2 s?1, respectively). The three species utilized different strategies with regard to physiological and nutritional response, with V. japurensis, regardless of treatment, using these limiting resources most efficiently to colonize abandoned pastures. Trees growing on the P + Ca but not +P alone plots increased A rates, indicating that Ca is an important limiting nutrient in post-pasture secondary succession. The addition of Ca as ash by burning primary and secondary vegetation could explain the rapid growth and dominance of V. japurensis in abandoned pasture areas in central Amazonia. The efficiency of Vismia to use limiting resources could lead to a restructuring of SF and altered rates of stand-level productivity.  相似文献   

13.
The aim of this paper is to evaluate and compare broadleaved cattail (Typha latifolia L.) biomass production and the nitrogen (N) and phosphorus (P) content in phytomass in three treatment wetland systems and to propose suitable areas for treatment wetlands in Estonia for raw material production. The biomass samples (roots/rhizomes, shoots with leaves and spadixes) and litter were collected from 1 m × 1 m plots—15 plots in the Tänassilma semi-natural wetland, 15 plots in the Põltsamaa free water surface (FWS) constructed wetland (CW), and 10 plots in the Häädemeeste FWS CW. The average aboveground biomass of T. latifolia varied from 0.37 to 1.76 kg DW m?2 in autumn and from 0.33 to 1.38 kg DW m?2 in winter. The greatest average nitrogen (22,950 mg N kg?1) concentration was found in spadixes in 2002, and the phosphorus (6500 mg P kg?1) concentration was measured in roots–rhizomes in 2003. Average standing stock of nitrogen and phosphorus was higher in aboveground than belowground phytomass. In FWS CWs with high hydraulic and nutrient loadings, however, the harvesting of aboveground biomass is not an effective means for the removal of nutrients. Cattail biomass is a valuable insulation material, whereas the fibre from spadixes mixed with clay gives elasticity to clay plasters. According to our estimates, about 5412 km2 could be used for Typha cultivation in Estonia.  相似文献   

14.
The vegetation portion of the Florida Wetland Condition Index (FWCI), an index of biological integrity, provided consistent and repeatable measures of condition at eighteen wetlands sampled in two consecutive growing seasons. The sample wetlands reflected a gradient of adjacent land use from non-impacted reference areas to wetlands imbedded within silviculture, cattle pasture and residential areas. Wetlands were described as herbaceous depression (n = 6), forested depression (n = 5) and forested strand or floodplain wetlands (n = 7), and represented different states of succession. Even though the wetlands were unique from one another and occurred across a large geographic area in Florida, the FWCI results calculated for all the wetlands were representative of adjacent land use impacts and not sensitive to natural variation. During the duration of this study, changes in weather from drought to tropical storm conditions, as well as management activities such as fire and herbivory, impacted wetlands. These effects were apparent in the change of species composition between sampling periods; 23–56% of species were different when resampled. Even though composition changed, the proportion of indicators remained consistent. The resulting condition scores suggested a one-to-one relationship between sampling periods.  相似文献   

15.
《Mammalian Biology》2014,79(5):331-337
Drivers of distribution patterns of poorly known species are among the most important aspects in conservation biology. We studied the proportion of area occupied by the large spotted genet (Genetta tigrina) and the slender mongoose (Galerella sanguine) in response to land use variables using camera-trapping data in Drakensberg Midlands, South Africa. Average estimated occupancy of large spotted genet and slender mongoose were 0.42 ± 0.10 and 0.41 ± 0.04 respectively using single season occupancy models. Altitudinal variation was found to be significant in the distribution of both species, along with human abundance for genet and availability of bushland for mongoose. Autumn influenced detection probability of both species negatively, while summer influenced slender mongoose positively. Relative human abundance was positively associated with detection probability of slender mongoose, and for large spotted genet, availability of bushland influenced positively while relative abundance of jackal (Canis mesomelas) influenced negatively. Occurrence of both species suggests that high elevations may not provide favourable ecological conditions, and bush cover appeared to be favourable habitats for both species. Either positive occurrence or detection of small carnivores to human abundance indicated their tendency to subsist in low-lying human populated areas. The present study shows the influence of a range of factors on the distribution of lesser known carnivores.  相似文献   

16.
The frequency of Viburnum lantana L. plants showing visible foliar symptoms (VFS) was assessed in Trentino, north Italy in 2010, 2012, 2014 and 2015. The assessment was based on a sub-sample (n = 10) of the ViburNeT observation plots network installed in 2010 according to a stratified random design. Depending on the year, a range of 193–232 plants were assessed during August. The frequency of symptomatic plants varied from 20.7 to 50.6%. Mean May-July hourly ozone concentration measured by conventional monitors over the same area and period varied from 37.9 to 45.8 ppb. There was a consistent time pattern between ozone and VFS. Consistency is confirmed if also a pilot survey carried out in 2009 is taken into account. Results are promising and supportive of the use of V. lantana as in-situ bioindicator for monitoring ozone impact on vegetation in forest areas.  相似文献   

17.
《Inorganica chimica acta》2006,359(1):339-345
Chemical oxidation in acetonitrile of the previously reported phenolato-bridged binuclear Mn(II) complex [(mL)MnMn(mL)]2+ (1), where mLH is pentadentate N,N′-bis-(2-pyridylmethyl)-N-(2-hydroxybenzyl)-N′-methyl-ethane-1,2-diamine ligand [C. Hureau, et al., Chem. Eur. J. 2004, 10, 1998–2010] using iodosylbenzene PhIO (dissolved in methanol) is described. The addition of one to four equivalents of PhIO per Mn ion leads to the transient formation of the mono-μ-oxo binuclear Mn2(III,III) complex [(mL)Mn(μ-O)Mn(mL)]2+ (2), previously studied. After addition of five equivalents of PhIO per Mn ion, the mononuclear Mn(III) species [(mL)Mn(OMe)]+ (3) is quantitatively generated. The UV–Vis spectrum of 3 displays a broad band at 456 nm (ε = 1000 L mol−1 cm−1) attributed to phenolato to Mn(III) charge transfer transition. Complex 3 exhibits a reversible oxidation wave at E1/2 = 0.68 V versus SCE, and the mononuclear Mn(IV) complex [(mL)Mn(OMe)]2+ (3ox) can thus be generated by exhaustive electrolysis at 1.0 V versus SCE. The 9.4 GHz EPR spectrum of complex 3ox shows a strong transition near g = 4 consistent with a rhombically distorted S = 3/2 system with a zero-field splitting dominating the Zeeman effect. UV–Vis spectrum displays a large phenolato to Mn(IV) charge transfer transition at 670 nm (ε = 2450 L mol−1 cm−1).  相似文献   

18.
《Mammalian Biology》2014,79(4):268-276
The Balkans are one of the last large refugia for brown bear (Ursus arctos) populations in Europe, and Bulgaria, in particular, contains relatively large areas of suitable brown bear habitat and a potential population of more than 600 individuals. Despite this, the majority of brown bear research remains focused on bear populations in Central and Western Europe. We provide the first assessment of genetic population structure of brown bears in Bulgaria by analysing tissue samples (n = 16) as well as samples collected with noninvasive genetic methods, including hair and faecal samples (n = 189 and n = 163, respectively). Sequence analysis of a 248 base pair fragment of the mitochondrial control region showed that two highly divergent mitochondrial European brown bear lineages form a contact zone in central Bulgaria. Furthermore, the analysis of 13 polymorphic microsatellite markers identified 136 individuals and found substantial genetic variability (He = 0.74; NA = 8.9). The combination of both genetic markers revealed the presence of weak genetic substructure in the study area with considerable degrees of genetic admixture and the likely presence of migration corridors between the two subpopulation in the Rhodope Mountains and Stara Planina as evidenced from the genetic detection of two male long-distance dispersers. A detailed assessment from densely collected samples in the Rhodope Mountains resulted in a population size estimate of 315 (95% CI = 206–334) individuals, indicating that not all available habitat is presently occupied by bears in this region. Efficient management plans should focus on preserving connectivity of suitable habitats in order to maintain gene flow between the two Bulgarian brown bear subpopulations.  相似文献   

19.
A Kraft pulp mill effluent was used as the inoculum to form microbial bioanodes under controlled potential at +0.4 V/SCE. Samples were collected at the inlet and outlet of the aerated lagoon of the treatment line. The outlet sample allowed efficient bioanodes to be designed (5.1 A/m2), which included Geobacter and Desulfuromonas sp. in their microbial community. In contrast, the bioanodes formed with the inlet sample did not contain directly connecting anode-respiring bacteria and led to lower currents. It was necessary to re-form this bioanode at lower applied potential (−0.2 V/SCE) to select more efficient electroactive species and increase the current density to 5 A/m2.  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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