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1.
The mosaic of trees, shrubs and open grassland in mesic African savannas is highly dynamic and strongly influenced by mammal herbivory and fire. We investigated the bird fauna in four different savanna habitats to help assess the impacts of vegetation change on this component of faunal diversity. Birds were censused, plant species were identified and vegetation structure was measured in four different vegetation types (Acacia nilotica woodland, Acacia nigrescens woodland, broadleaf thicket and open grassland) in the Hluhluwe-Umfolozi Park in northern KwaZulu Natal, South Africa. Multivariate ordination analyses were used to determine the relative importance of vegetation structure and floristic composition in defining bird assemblages. The bird communities of the grasslands, the acacia woodlands, and the broadleaf woodlands were clearly separated on the first axis of the detrended canonical correspondence analysis (DCCA). Canopy cover and foliage height diversity (FHD) were strongly correlated with the first axis of DCCA, possibly reflecting a secondary successional series from grassland to woodland, known as bush encroachment. Floristic composition (based on presence–absence data only) seemed to be less important for bird community composition than vegetation structure. The results indicate that changes in vegetation structure, caused by bush encroachment, could cause concomitant changes in bird community composition.  相似文献   

2.
Abstract: Researchers have obtained mixed results in studies that use prebaiting to enhance small mammal trapping success. In 2004–2005 we tested the effects of prebaiting on small mammal trapping success in an exotic and invasive shrub community, Morrow's honeysuckle (Lonicera morrowii), using 4 80 × 120-m live trapping grids at Fort Necessity National Battlefield in Fayette County, Pennsylvania, USA. We randomly assigned traps to 1 of 3 trapping methods: we prebaited one-third of the traps 2 nights (n = 3,508 trap-nights), one-third one night (n = 3,492 trap-nights), and one-third had no prebaiting (n = 3,509 trap-nights). We compared small mammal richness, diversity, and relative abundance (no. captures/100 trap-nights) of white-footed mice (Peromyscus leucopus; n = 462 captures), meadow voles (Microtus pennsylvanicus; n = 89 captures), meadow jumping mice (Zapus hudsonius; n = 221 captures), masked shrews (Sorex cinereus; n = 87 captures), and shorttail shrews (Blarina brevicauda; n = 78 captures) among prebaited traps and non-prebaited traps. On the first day of trapping, as well as all 4 days combined, richness, diversity, and relative abundance for all species were similar among traps that we had prebaited for 2 nights, one night, and zero nights (P = 0.856). Moreover, total number of captures was similar among prebaiting treatments (P = 0.197). These results suggest that prebaiting does not enhance trapping success for small mammals in a landscape dominated by a dense, exotic shrub. We recommend that managers do not employ prebaiting in areas with similar small mammal species composition in an attempt to increase trapping success, as we did not record a difference in trapping success in prebaited traps compared to non-prebaited traps.  相似文献   

3.
Anthropogenic noise is becoming more prevalent in the world and has been shown to affect many animal species, including birds. The impact of such noise was measured in Neotropical urban parks to assess how the noise affects avifauna diversity and species richness. We sampled bird species, and concurrently measured sound pressure (noise) levels (Leq, equivalent noise levels) in eight urban green areas or parks located in a large city (Belo Horizonte) in south‐eastern Brazil over a 1‐year period. The diversity of sampled points was measured by means of total species richness, Fisher's alpha and Shannon–Wiener diversity indices. Noise levels within all parks were greater than those in natural areas. We found that an increase in noise levels and the area of open habitats surrounding sampling points were negatively related to species richness. Social factors reflecting increased urbanization, such as higher incomes, were also negatively correlated with bird species richness. However, noise was the factor that explained most of the variance. These results suggest that anthropogenic noise can have a significant negative impact on the conservation value of urban parks for bird species.  相似文献   

4.
Abstract: We examined the influence of both local habitat and landscape variables on mammal species abundance in a forest fragmented by road construction and in continuous forest in 8 study sites in Mt. Chirisan National Park, South Korea, from 2001 to 2004. We recorded tracks of 8 species of mammals, Siberian weasels (Mustela sibirica), yellow-throated martens (Martes flavigula), Bengal cats (Felis bengalensis), wild boars (Sus scrofa), water deer (Hydropotes inermis), roe deer (Capreolus capreolus), Korean hares (Lepus coreanus), and red squirrels (Sciurus vulgaris), on the snow on 8 2-km transects in our study areas. There were significant differences in density of snags, mean tree basal area, and in shrub coverage between the fragmented and unfragmented forest areas. We found significant differences in abundance index of tracks between the fragmented and unfragmented areas for 5 mammal species; the others had even distributions. Of the 8 mammal species analyzed, 5 species related to landscape and local vegetation variables in a stepwise approach with repeated measures. Landscape variables are significant predictors of abundance for many mammal species. Forest managers should consider multiple measures of forest fragmentation sensitivity when making forest management decisions.  相似文献   

5.
自然保护区的物种编目和常规监测是区域性和全国性生物多样性研究与监测的基础,而红外相机技术已被广泛应用于地栖鸟兽的物种编目和动态评估。本研究在贵州赤水桫椤保护区及其周边地区采用红外相机公里网格(1 km×1 km)法,选取保护区内2个样区和1个区外样区,每个样区内选取20个连续网格布设相机,系统开展鸟兽多样性监测。2016年12月至2019年12月,经过累积55 029个相机日的调查,获得动物和非工作人员的独立有效照片21 243 张,从中鉴定出野生兽类4目10科17属21种,鸟类6目13科29属34种。其中有8种为保护区的新纪录物种;所鉴定的兽类和鸟类中属国家Ⅱ级重点保护野生动物的分别为4种和8种;被列入《中国脊椎动物红色名录》易危(VU)的有8种、近危(NT)的有13种 。相对丰富度指数(RAI)处于前三位的兽类依次是毛冠鹿(Elaphodus cephalophus)、小麂(Muntiacus reevesi)、藏酋猴(Macaca thibetana);鸟类依次是紫啸鸫(Myophonus caeruleus)、灰胸竹鸡(Bambusicola thoracicus)、画眉(Garrulax canorus)。对比分析初步显示保护区内监测到的兽类物种数和多样性(香农-威纳)指数明显高于周边地区;核心区和缓冲区的鸟兽相对丰富度和多样性指数较实验区高;保护区内在700~1000m海拔带监测到的物种数(尤其兽类)较多,但 > 1 000 m的海拔带物种多样性指数最高。本次调查结果为保护区提供了重要的兽类和鸟类资源信息,也为促进保护区鸟兽编目和重要物种的生态学研究,以及优化管理对策、实现生物多样性长期监测和有效保护提供了数据支持。  相似文献   

6.
An investigation of gamasid mites on the body surface of small mammals was carried out in Yunnan Province of China from 1990 to 2004. The small mammal hosts were captured from 25 counties which represent five geographical subregions, namely Middle Subregion of Hengduan Mountains, Southern Subregion of Hengduan Mountains, Eastern Plateau Subregion of Yunnan, Western Plateau Subregion of Yunnan and Southern Moun- tainous Subregion of Yunnan. The captured 10 803 small mammal hosts belong to nine families, 29 genera and 52 species in four orders (Rodentia, Insectivora, Scandentia and Lagomorpha). A total of 68 571 gamasid mites were collected from the body surface of the captured small mammal hosts and all the gamasid mites were identified to 10 families, 33 genera and 112 species. This paper lists all the mite species, together with their taxonomic position (genera and families) and their corresponding hosts. Much more mite species were found in the Middle Subregion of Hengduan Mountains than in other geographical subregions. The total individuals of mites and small mammals in the Middle Subregion of Hengduan Mountains are also the most plentiful in the five geographical subregions. Three dominant mite species and three dominant small mammal hosts were determined as the dominant species in the investigated areas of Yunnan Province. The dominant hosts are Rattus flavipectus (which accounts for 34.85% of the total individuals), Apodemus chevrieri (13.43%) and Rattus norvegicus (10.40%) while the dominant gamasid mite species are Laelaps nuttalli (Hirst, 1915) (27.84%), Laelaps echidninus (Berlese, 1887) (18.38%) and Laelaps guizhouensis (Gu et Wang, 1981) (14.79%). The results showed the high species diversity of gamasid mites in Yunnan Province and the uneven distribution feature in different subregions.  相似文献   

7.
Small mammal species diversity in the major vegetation zones of Bwindi Impenetrable National Park is discussed in relation to altitude. Species richness of the small mammals was found to decrease with an increase in altitude. The main factors accounting for the observed diversity are the wide altitudinal variation and a complex array of vegetation types. Sixty‐seven species of rodents and shrews were found to exist in the Park; 47 of which were rodents and 20 shrews. Of these, 26 species are new to the Bwindi Park list. Three species have probably not been described before. The study found 10 species of small mammals to be Albertine Rift endemics. Three genera are recorded in Uganda for the first time: Rwenzorisorex, Suncus and Paracrocidura. Five species are new records for East Africa. These are Crocidura stenocephala, Lophuromys rahmi, L. medicaudatus, Paracrocidura maxima and Hylomyscus aeta. Because of the high endemism of plants, butterflies, birds and now of small mammal species, Bwindi forest is a unique biodiversity hotspot and is among the highest conservation priorities in the Albertine Rift.  相似文献   

8.
Understanding species distributions, habitat requirements, and population trends is helpful for implementing effective conservation. But expense often prevents such evaluations. Here, we present a preliminary assessment for a low‐cost method – road‐side observations – to see how effective it can be. The bamboo zone of Bwindi Impenetrable National Park is restricted, covering 0.3% of park area yet is poorly known. Our study evaluates the use of the bamboo zone and surrounding forest by species of large mammals and large ground birds. Data were collected while driving a road section running through this zone. During 416 trips, seven species of mammal and one bird were recorded. Distributions for most species were significantly nonrandom in both space (P < 0.02) and time (Hour of day: P < 0.040; Month: P < 0.0001) for all species but black‐fronted duikers and blue monkeys for which 0.085 > P > 0.050 for month. Of the species observed, francolins were more frequently seen in the zone of visible bamboo than the nonbamboo zone (P = 0.002). Black‐and‐white colobus, L’Hoest’s monkey, and jackals were more common in nonbamboo forest (P ≤ 0.05). Road sightings have potential for low‐cost habitat use assessments and monitoring.  相似文献   

9.
Wildlife-Habitat Restoration in an Urban Park in Southern California   总被引:2,自引:0,他引:2  
Within an urban park in southern California, the relationship between the structure and floristics of vegetation and the distribution, abundance, and behavior of wildlife was studied in relatively undisturbed areas (San Luis Rey) and in contiguous areas (Guajome Park) in need of restoration. These data were used to develop recommendations for the enhancement of native animal species in the park. The abundance of amphibians and reptiles was highest in native upland scrub and willow (Salix)-riparian vegetation types, and lowest in dry, disturbed sites. Western fence lizards (Sceloporus occidentalis) were the most abundant reptile throughout both study areas. Overall, bullfrogs (Rana catesbiana), an exotic species, were the dominant amphibians; the native Pacific treefrog (Hyla regilla) was rare throughout. At both study areas, the small mammal community was dominated by western harvest mice (Reithrodontomys megalotis) and deer mice (Peromyscus maniculatus) and, to a lesser extent, by brush mice (P. boylii) and exotic house mice (Mus musculus). Negative correlations in abundance existed between house mice and harvest mice, and between house mice abundance and overall small mammal abundance. In riparian sites, cottonwood (Populus fremontii) and various height classes of willow were the dominant factors in the majority of bird abundance–habitat‘correlations and where foraging activities were concentrated. Recommendations for enhancing native animal species include reduction of marsh sedimentation, removal of feral species, and development of connections between the park and nearby natural areas. A corridor of native riparian vegetation (primarily cottonwood-willow) should be developed to replace the existing agricultural fields, thereby linking Guajome with the San Luis Rey River.  相似文献   

10.
Tripsacum section Fasciculata is characterized by staminate spikelet pairs in which one spikelet is sessile and the other is supported by a long and slender pedicel. In section Tripsacum both spikelets of a staminate pair are sessile, or one is supported by a short and stout pedicel. Section Fasciculata includes five closely allied species. Tripsacum lanceolatum Ruprecht ex Fournier (2n = 72) extends from Durango in Mexico to the Huachuca mountains of southern Arizona. It resembles T. jalapense de Wet & Brink spec. nov. (2n = 72) from Guatemala in having terminal inflorescences with 3–10 racemes, but they differ in growth habit and are genetically isolated. Terminal inflorescences of the remaining three species have 15–50 racemes. Tripsacum laxum Nash (2n = 36) from the eastern escarpment of the Central Mexican Plateau is the only species of the group with essentially glabrous basal leaf-sheaths. It resembles the more widely distributed T. maizar Hernandez & Randolph (2n = 36, 72) in respect to inflorescence morphology, but is genetically isolated from this species. The widely distributed T. pilosum Scribner & Merrill (2n = 72) was divided into var. pilosum and var. guatemalense de Wet & Brink var. nov.  相似文献   

11.
Eric Sande 《Ostrich》2013,84(1-2):64-68
Sande, E. 2000. Understorey bird species diversity and abundance in three forest types of Semuliki National Park, Uganda. Ostrich 71 (1 & 2): 64–68.

Semuliki National Park is a rich lowland forest in terms of biodiversity. The bird species list currently stands at 428, of which 31 species occur nowhere else in East Africa. Although the park was severely encroached for agricultural activities, all the encroachers were evicted and many species of birds still survive. A total of 61 species with 1270 individuals were trapped from all the forest types. There was no significant difference in the species diversity between the swamp, mixed and Cynometra forest types. The Little Greenbul, Yellow-whiskered Greenbul, Slender-billed Greenbul, and Olive Sunbird were significantly more abundant in the mixed forest than in the swamp forest while the arboreal insectivore frugivores, terrestrial insectivores and sallying insectivores were significantly more abundant in the Cynometra than in the swamp forest type.  相似文献   

12.
We quantified broad-scale patterns of species richness and species density (mean # species/km2) for native and non-indigenous plants, birds, and fishes in the continental USA and Hawaii. We hypothesized that the species density of native and non-indigenous taxa would generally decrease in northern latitudes and higher elevations following declines in potential evapotranspiration, mean temperature, and precipitation. County data on plants (n = 3004 counties) and birds (n=3074 counties), and drainage (6 HUC) data on fishes (n = 328 drainages) showed that the densities of native and non-indigenous species were strongly positively correlated for plant species (r = 0.86, P < 0.0001), bird species (r = 0.93, P<0.0001), and fish species (r = 0.41, P<0.0001). Multiple regression models showed that the densities of native plant and bird species could be strongly predicted (adj. R2 = 0.66 in both models) at county levels, but fish species densities were less predictable at drainage levels (adj. R2 = 0.31, P<0.0001). Similarly, non-indigenous plant and bird species densities were strongly predictable (adj. R2 = 0.84 and 0.91 respectively), but non-indigenous fish species density was less predictable (adj. R2 = 0.38). County level hotspots of native and non-indigenous plants, birds, and fishes were located in low elevation areas close to the coast with high precipitation and productivity (vegetation carbon). We show that (1) native species richness can be moderately well predicted with abiotic factors; (2) human populations have tended to settle in areas rich in native species; and (3) the richness and density of non-indigenous plant, bird, and fish species can be accurately predicted from biotic and abiotic factors largely because they are positively correlated to native species densities. We conclude that while humans facilitate the initial establishment, invasions of non-indigenous species, the spread and subsequent distributions of non-indigenous species may be controlled largely by environmental factors. The U.S. Government’s right to retain a non-exclusive, royalty-free licence in and to any copyright is acknowledged.  相似文献   

13.
Recovery of Bird Species in Minimally Restored Indonesian Tin Strip Mines   总被引:1,自引:0,他引:1  
Bird species richness and individual abundances were recorded in old, unrestored tin strip mine plots, in mined plots restored 1, 2, and 3 years before the study, and in adjacent, unmined, natural secondary forest plots on the 11,340‐km2 Indonesian island of Bangka (2°S, 106°E). The objective was to assess the ecological recovery of unrestored and minimally restored mine plots compared with surrounding reference forest. Unrestored mines had not been mined or used for any other purpose for 14–30 years; plots in their first, second, and third year since restoration were old mines planted with Acacia mangium (Leguminosae) at a density of 400 trees/ha. Natural secondary forest plots 20 or more years since the last disturbance were immediately adjacent to both unrestored and restored plots. Bird surveys on 4‐ha plots were performed during the 1995 breeding season. A comparison of data from unrestored plots of widely varying ages showed no significant differences among them for species richness, diversity (Shannon–Wiener index, H′), or individual abundance, indicating that little natural bird community recovery had occurred over time in the plots. However, increases did occur in restored sites over only 3 years for both species richness (r 2 = 0.29, p = 0.04) and diversity (r 2 = 0.45, p = 0.009). All values for third‐year restored plots, however, were still significantly lower than corresponding values for adjacent natural secondary forest plots. The quick return of bird activity on the plots after minimal efforts at restoration supports the idea that simple, inexpensive restoration can be effective for “jump starting” degraded systems at large scales. Such a restoration strategy might be of particular value for degraded land in developing nations, where scientific, professional, and financial resources might be in short supply. Using this strategy, a small number of restoration professionals could mobilize the labor of many local people in many areas, serving to both improve ecological systems and to educate and engage local populations in restoration and conservation projects.  相似文献   

14.
中国不同地理区域鸟兽物种丰富度的相关性   总被引:9,自引:0,他引:9  
生物类群之间物种丰富度的相关性研究是当前物种多样性研究中的热点问题之一,目前,中国尚无相关的研究报道。我们收集了中国三种区域类型:动物地理亚区、行政区和保护区的鸟兽名录,分析了行政区与保护区、动物地理区和经纬度带中鸟兽物种数比值及其相关性。 结果表明:不同区域、动物地理区和经纬度带中鸟兽物种数都显著相关。保护区尺度鸟兽物种 数的相关系数为0.818和动物地理区中的华北区为0.768,其他所有区域和地理区域的鸟兽物 种数的相关系数都高于0.850。因此,鸟兽物种数的相关关系在一定程度上具有预测价值。我们发现不同区域鸟兽物种数比值无显著性差异;但是,不同区域间鸟兽物种数 比值差异显著。该比值在中国呈中间低四周高的分布趋势,其中东北地区最高。我们还利用历史累积调查数据与非历史累积调查数据进行了鸟兽物种数比值及其相关性分析,发现利用累积数据计算的相关性低于非累积数据计算的相关性,但利用累积数据计算的鸟兽物 种数比值高于非累积数据计算的比值。最后,探讨了为什么鸟类与兽类的物种数目会相关。我们根据物种-面积公式,S=CAZ,导出了两个生物类群物种丰富度的相关关 系式。利用全国不同区域数据拟合,得到Z1/Z2=0.913,Z1/Z2接近于1。于是 ,C1/C2可视为近似等于Ram。本研究可推广到其他不同生物类群物种。物种数量的相关关系为快速评估区域的物种多样性提供了一条途径。  相似文献   

15.
Meadows in river deltas are characterized by a high diversity and abundance of small mammals. However, neither their spatial arrangement nor differences in their use of microhabitat can necessarily explain the dense co‐occurrence of sympatric species. We investigated how several small mammal species share a seasonally flooded meadow of limited size, testing predictions (P1) that herbivore, granivore, insectivore, and omnivore species are separated in time (dominant in different years), (P2) that sympatric species undergo isotopic partitioning, and (P3) that there are intraspecific differences in diet. Stable carbon and nitrogen isotope signatures in the hair of seven synantropic shrew, vole, and mice species were used as a proxy for their diet. We found that the three most abundant species in eight of the nine years were from different diet groups. However, based on the number of species in the functional groups, the state of small mammal community was considered unfavored in five out of the nine investigation years. In years with the greatest dominance of Apodemus agrarius, the small mammal community was characterized by decreased diversity and Micromys minutus was either in low abundance or absent. In 2014 and 2016, years of low abundance or absence of M. oeconomus, M. agrestis, and M. glareolus were both recorded in high numbers. Differences in the isotopic signatures of the three most abundant small mammal species in the community were clearly expressed and core areas in the isotopic space were separated, showing their dependence on different dietary resources. Intraspecific dietary separation between young and adult animals was observed only in M. oeconomus. Thus, the high species diversity of small mammals and the formation of their community in this investigated flooded meadow are maintained by isotopic partitioning (segregation in dietary space) and by changes in their number over time (shifting dominance).  相似文献   

16.
Isolated trees have distinctive economic, social and cultural value for the Betsileo people living on the edge of the protected forest corridor between Ranomafana and Andringitra national parks, in South-East Madagascar. Many of these trees are Ficus spp., traditionally protected and respected. At the landscape level, they are isolated features in a heterogeneous mosaic, providing fruit, shade and aesthetic services in open cultivated areas. Within the current management system, isolated trees may also contribute significantly to the provision of ecological services by enhancing bird diversity in open areas outside the forest. We identified practices and values linked to isolated tree uses and management through ethnographic data collection. Bird presence and abundance were sampled by 338 point counts in isolated trees and open areas of the agricultural mosaic. Isolated trees were occupied by 18 out of 32 (56%) bird species in the agricultural mosaic, including 8 (25%) endemic forest species. Endemic forest birds were significantly more numerous in isolated trees than in open habitats, both in species richness and abundance (mean P value < 0.001). Overall bird species richness was significantly higher in open areas containing isolated trees, than in areas without isolated trees. Bird species richness in Ficus spp. was significantly higher than in other isolated tree species, although no differences were detected in abundance or within guilds. Community-based management of isolated trees may thus represent an opportunity for convergence between bird conservation goals outside protected areas and local management values and practices.  相似文献   

17.
Dung beetles are predominantly coprophagous and use mammalian faeces as their main food resource and for offspring rearing. However, these resources are generally ephemeral and scarce. The objective of this study was to verify the attractiveness to dung beetles of the faeces of nine native mammal species of the Cerrado biome in different trophic guilds. This study was conducted during the rainy season (October 2016 to March 2017) in two sensu stricto areas of the Cerrado in the Brasília National Park (PNB), Federal District, Brazil. Pitfalls containing faeces of nine mammals native to the region were used as bait (from three herbivores, three carnivores and three omnivores) for the collection of dung beetles. We collected 203 individuals and 19 species, and the most abundant species were Uroxys aff. thoracalis, Oxysternon palemo, Coprophanaeus spitzi and Diabroctis mirabilis. The most attractive faecal bait was from the omnivorous Chrysocyon brachyurus (32.67% of the individuals and 13 species). This study reveals variation in the attraction of dung beetles to native mammal dung of the Cerrado, with more abundance in the faeces of omnivores and carnivores and less in the faeces of herbivores. The species composition in the carnivore baits did not differ from that of the omnivore baits. These data indicate that changes in Scarabaeinae assemblages result from changes in mammal species such as those that have occurred in the Cerrado biome with the conversion to cattle production, which in recent years has caused intense fragmentation of habitats, expansion of agricultural and livestock activities and the introduction of exotic species. The mammal C. brachyurus, vulnerable to extinction in Brazil, should be a focus for future research, since its faeces support a great diversity of dung beetles in the Cerrado.  相似文献   

18.
Poaching and habitat destruction across sub-Saharan Africa brought the black rhinoceros (Diceros bicornis) close to extinction. Over the past few decades, however, one of four subspecies, D. b. bicornis, has experienced a significant population increase as a consequence of its protection within Etosha National Park (ENP), Namibia. We report here on the level and spatial distribution of black rhinoceros genetic diversity within ENP. Using nine microsatellite loci, genetic variation was assessed from 144 individuals. Our results are consistent with the observation of lower levels of genetic diversity in D. b. bicornis, when compared to D. b. michaeli, but greater diversity when compared to D. b. minor. We also showed that ENP’s black rhino genetic diversity is well represented in Waterberg National Park, originally founded with ENP individuals. We found no genetic signature of a recent bottleneck in ENP, however, suggesting that the genetic diversity within ENP has not been adversely affected by the recent severe population decline. Using Bayesian clustering methods, we observed no significant population structure within ENP, but positive spatial genetic correlation is observed at distances up to 25 km. This relationship exists in females but not males, suggesting reduced dispersal among females, the first evidence of limited female dispersal or philopatry in any species of rhinoceros.  相似文献   

19.
Conservation shortcuts such as umbrella species have been long used for regional protection of species whose distributions are poorly known. Although the European large carnivores—brown bear, gray wolf, and Eurasian lynx—might seem to be robust candidates as umbrella species, their actual effectiveness has been challenged. We used 10-km resolution distribution maps of mammals (n = 10) and birds (n = 55) of European conservation concern in the Romanian Carpathians, and a temporal sequence of land cover maps (1990, 2000, and 2006) to examine: (1) the spatial overlap in distribution between large carnivores and bird and mammal species of conservation concern, (2) changes in forest cover for the Romanian Carpathians during the post-communist period in relation to the distribution of species, and (3) priority conservation areas using carnivores as umbrella species. Approximately 55% of the bird and 80% of mammals species included in this study would potentially benefit from using large carnivores as conservation surrogates. The changes in forest cover during 1990–2006 were concentrated in the Eastern Carpathians, where up to 45% of the forest per mapping unit was clearcut during the study period. Implicitly, the areas of occupancy of the background species were most disturbed by clearcutting in the Eastern Carpathians. We propose that the large carnivores could act temporary as umbrella species in areas that are still relatively undisturbed, such as Southern and Southwestern Carpathians. This alternative conservation strategy will allow time for (1) the new established protected areas to start efficiently and (2) the forestry practices to switch from mostly uncontrolled clearcutting, lacking landscape scale management to ecologically-based practices.  相似文献   

20.
Ecosystem functionality is an increasingly important objective of ecological restoration. Despite this, a few studies have rigorously assessed reproductive functionality within restored plant populations, and it is largely assumed that pollinators follow restoration of plant communities—“build it and they will come.” Here, we applied an ecological genetic approach to determine the impact of spatial separation on mating in Banksia menziesii (Proteaceae), a dominant bird‐pollinated species of Banksia woodlands of Western Australia. All plants at three post‐mining restored sites (n = 72 [13 years old], n = 21 [8 years old], and n = 20 [9 years old]), as well as a sample from an adjacent natural reference site (n = 42), were genotyped at nine microsatellite loci. Seed set, mating system parameters, realized pollen dispersal through the assignment of paternity to seed, and avian pollinator species composition, abundance and behavior, were assessed. All patches displayed equivalent heterozygosity (He = 0.53–0.59) and very weak genetic divergence (FST ≤ 0.01). Seed of plants within restored sites showed complete outcrossing and relatively high seed set, 26% of which were sired by pollen donors located beyond the local patch. Similar abundance and movement of nectar‐feeding birds was observed in restored and natural sites, despite lower bird species diversity in the restored site, where a smaller, less aggressive species was dominant. Our results demonstrate the restitution of wide outcrossing in these restored Banksia patches within an active mine‐site, and suggest that restored bird‐pollinated Banksia populations are resilient to human impacts, due largely to their generalist pollinator requirements and highly‐mobile avian pollinators.  相似文献   

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