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1.
《Journal for Nature Conservation》2014,22(2):166-175
Semiarid Mediterranean areas patchily forested with Pinus halepensis Mill. are often affected by urbanisation plans, which influence the conservation of biodiversity in the remaining fragments. We assessed forest biodiversity in eleven Pinus halepensis patches of the municipality of Murcia (SE Spain), on the basis of the abundance, richness and conservation value of birds and woody flora. Under the hypothesis that biodiversity is conditioned by pine density, modulated by other patch features (age, physical substrate, surrounding land uses), mixed regression models were used to relate biodiversity indicators with environmental gradients, detected through principal component analyses (PCAs) performed on three sets of variables: landscape (L); habitat structure (H); and, stand development (S). PCA-L related patch size and connectivity to the abundance of typical woodland birds and to floral and bird species richness. PCA-H related shrub cover associated with Sylvia melanocephala Gmelin., to rock and dry grassland cover, a feature of moderately disturbed areas preferred by Lanius senator L. PCA-S associated taller trees and better physical conditions with canopy dwelling and soil probing bird species, respectively. The bird or plant conservation value of patches did not generally match their protection status, which was confirmed by the analysis of a larger sample of 36 natural patches. A negative relationship between floristic value and pine density suggests that reducing the density of reforestations can lead to more diverse and self-sustaining wooded formations. In contrast, conservation value for birds did not decrease with reforestation, stressing the need to use ornithological and floristic indexes as complementary assessment tools. The results seem useful for building a municipal network of reserves connecting higher status protected areas. 相似文献
2.
Daniel Brito Leonardo C. Oliveira Marco Aurlio R. Mello 《Journal for Nature Conservation》2004,12(4):219-228
Atlantic Forest mammals are still poorly known and very few localities have been properly surveyed and/or studied. Protected reserves are of paramount importance for the conservation of native flora and fauna. Hereby we provide a survey of mammals captured and/or observed in Poço das Antas Biological Reserve, the largest lowland Atlantic Forest reserve in Rio de Janeiro state, southeastern Brazil. A total of 77 species were recorded, several of them endemics and/or listed as threatened either by IUCN's Red List, by the Brazilian Red List or by the regional Red List of Rio de Janeiro State. Mammals are threatened in several ways in this area: (1) habitat loss and fragmentation, (2) road mortality, (3) fires, (4) poaching, (5) cattle grazing, (6) pollution, (7) exotic species, and (8) feral populations of dogs Canis familiaris and cats Felis catus. Despite all threats, this is an important site for biodiversity conservation and scientific research. Better management and more investment would surely improve its effectiveness in protecting Atlantic Forest mammals. 相似文献
3.
Luiz Menini Neto Rafaela Campostrini Forzza Daniela Zappi 《Biodiversity and Conservation》2009,18(14):3785-3807
Epiphytes play an important role in the flora and ecology of the tropical regions. Most floristic studies within the state
of Minas Gerais focus on terrestrial, woody plant diversity, but this is a different approach, looking at epiphytic angiosperms
in three highland areas in Southeastern Minas Gerais, namely Mata do Baú (MB), Reserva Biológica da Represa do Grama (RBRG)
and Parque Estadual de Ibitipoca (PEI). Regular collections were performed in these sites between 1999 and 2007, complemented
by herbarium records for PEI, and 181 species of epiphytic angiosperms were recorded in 66 genera, within 12 families. Orchidaceae,
with 89 species, was by far the largest, and the most species rich genera were Peperomia (Piperaceae) and Pleurothallis
s.l. (Orchidaceae), with 12 species each. Similarity analysis has shown a closer relationship between MB and RBRG, both composed
by seasonal semideciduous forest, however, Jaccard (0.163) index are low. A similarity analysis including other 21 areas of
southeastern and southern Brazil revealed strong influence of sazonality, vegetation type and altitude in the composition
of the epiphytic flora, and a relative independence regarding the geographic proximity of the areas sampled. From the conservation
standpoint, 30 species recorded for this work appear in the red list for the state of Minas Gerais, under different conservation
categories. The low similarity indices obtained between the studied areas underline the importance of the conservation of
each one of the remaining forest fragments in Minas Gerais, as their relative geographical proximity does not necessarily
mean that their epiphytic flora is similar. 相似文献
4.
Walter Barrella Abílio Gabriel Martins Miguel Petrere Jr. Milena Ramires 《Environmental Biology of Fishes》2014,97(12):1367-1376
The largest preserved areas of Atlantic Forest are located in the southeastern region of Brazil. Estuaries, mangroves, rivers and streams are home to a community of fish that is still poorly understood. The composition of fish species and their relationships with environmental conditions were used to identify homogeneous areas within a landscape of 33,000 km2. A total of 6,542 specimens, representing 124 species and 13 orders of bony fishes were collected at 102 sampling stations. Resulting scores from a canonical correspondence analysis applied to biological and environmental data were used in a cluster analysis to identify fish species with similar spatial distributions and localities with similar fish fauna and abiotic conditions. Five micro-regions were identified, with homogeneous compositions of species, allowing better planning of conservation of aquatic biodiversity. Despite a high degree of preservation, impacts due to deforestation, drainage of wetlands and overfishing were detected, as well as the introduction of 41 exotic species. 相似文献
5.
Fruits of cultivated and indigenous Solanaceae from Southeastern Brazil have been examined for the presence of trypanosomatid flagellates. The 14 species found infected were: Capsicum annuum, C. praetermissum, Lycopersicon esculentum, Nicandra physaloides, Physalis angulata, Solanum sp., S. americanum, S. concinnum, S. diflorum, S. erianthum, S. gilo, S. robustum, S. variable and S. viarum. The pentatomid hemipteran Arvelius albopunctatus experimentally transmitted flagellates to fruits of some species. Cultures of flagellates were obtained from fruits of eight species of Solanaceae and from A. albopunctatus. 相似文献
6.
Mogens Trolle 《Biodiversity and Conservation》2003,12(4):823-836
The Pantanal floodplain of southwestern Brazil, with its mosaic of marshes,seasonally flooded savannas, woodlands and forests, is known as one of thewildlife hotspots of South America. The region harbors a rich mammal fauna andis a stronghold for a number of mammal species; however, still very few thoroughmammal surveys have been conducted in the Pantanal. This is the first mammalsurvey from the southeastern part of the region. An intensive,three-month study of the medium to large, non-volant species wasconducted at a location in the upper Rio Negro Basin, Aquidauana region, MatoGrosso do Sul. Thirty species of mammals were recorded, including 5 xenarthrans,1 primate, 10 carnivores, 7 ungulates and 5 caviomorph rodents. It was possibleto analyze the field biology of many of the species to a level not previouslypublished for the Pantanal. Recommendations are given for camera trapping in thePantanal and the Amazon. Finally, the effects of intensive cattle ranching onconservation in the Pantanal are discussed. 相似文献
7.
Sarcophagidae (Diptera) are potential vectors of several pathogens. They are also very important in forensic entomology, providing basic information on the circumstances of death. The objective of this study was to determine the synanthropic index of adult Sarcophagidae collected in Rio Claro, state of São Paulo, southeastern Brazil. Sampling occurred between September 2009 and August 2010. Traps baited with sardines, beef liver, or minced meat were set for five consecutive days per month in three distinct ecological areas representing urban, rural, and forest environments. A total of 440 specimens of sarcophagids were collected. The most abundant species was Peckia (Sarcodexia) lambens (Wiedemann), followed by Oxysarcodexia thornax (Walker), Peckia (Euboettcheria) collusor (Curran & Walley), Peckia (Euboettcheria) sp., and Peckia (Pattonella) intermutans (Walker). The only species with positive synanthropic index values were O. thornax and P. (S.) lambens, which demonstrated a greater preference for inhabited areas. Peckia (Euboettcheria) florencioi (Prado & Fonseca), P. (P.) intermutans, and Peckia (Euboettcheria) australis (Townsend) were only found in the forested area, which demonstrates their importance in forensic entomology because of their preference for a particular type of environment. The greatest number of sarcophagids was found in the forest environment; however, only the forest and rural areas were significantly different in Sarcophagidae abundance. 相似文献
8.
Habitat loss and fragmentation are serious threats to biodiversity conservation in the Atlantic Forest. A network of protected reserves is essential to the protection of native fauna and flora. However, internal and external factors may threaten the preservation of biota, thus population viability analyses (PVA) are important tools in reserve design and management planning. A PVA was carried out, using the computer package VORTEX, to assess the effectiveness of the reserve network of Rio de Janeiro State in Brazil in retaining viable populations of the endemic marsupial Micoureus travassosi. The PVA takes into account demographic, genetic and environmental stochastic events and catastrophes (fire). Rio de Janeiro state has 31 reserves, and 20 of those were considered to retain viable populations for 100 years, whereas eight were predicted to suffer from genetic decay, two from both genetic decay and demographic stochasticity, and one of them probably has an extinct population. The minimum area of suitable habitat needed to maintain a minimum viable population of M. travassosi is estimated at 3600ha. Sensitivity analysis was run for mortality, sex ratio, percentage of reproductive females, inbreeding depression and probability of catastrophes, and suggests that inbreeding depression is important in small population sizes, whereas the effects of catastrophes were significant only for large populations. Although the model indicates that some populations will suffer from demographic and/or genetic stochasticity, the reserve network of Rio de Janeiro state will likely keep M. travassosi's populations for the next 100 years. 相似文献
9.
Summary Observations were made on the nectar-feeding of hummingbirds in three areas of natural forest in the coastal mountains of southeastern Brazil. Five of the seven hummingbird species observed are endemic to the region. The observations are summarised and discussed, and limited comparison is made with the feeding ecology of Andean hummingbirds. The data suggest that two plant families of prime importance in temperate forest in the Andes, the Rubiaceae and Ericaceae, are unimportant in southeastern Brazilian montane forest. The close fit between the bill ofPhaethornis eurynome and the corollas of three species of plants suggests coevolution. The data presented are preliminary and incomplete, and indicate the need for more thorough research into the relationships between hummingbirds and plants in this region.
Kolibris und die von ihnen besuchten Blüten im Küstengebirge Südostbrasiliens
Zusammenfassung Die Beobachtungen über blütenbesuchende Kolibris stammen aus drei Naturwaldgebieten im Küstengebirge Südostbrasiliens. 5 der 7 beobachteten Kolibriarten sind in dieser Region endemisch. Die Zusammenfassung der Beobachtungen gestattet unter Einschränkung gewisse Vergleiche mit der Nahrungsökologie andiner Kolibris. Die Daten machen wahrscheinlich, daß Rubiaceae und Ericaceae, zwei Pflanzenfamilien von vorrangiger Bedeutung in den Wäldern der gemäßigten Zone der Anden, im südostbrasilianischen Bergwald unwichtig sind. Die enge Anpassung des Schnabels vonPhaethornis eurynome an die Gestalt der Blütenkrone dreier Pflanzenarten läßt Koevolution vermuten. Die Beobachtungen sind jedoch unvollständig und forden weitere intensive Untersuchung der Beziehungen zwischen Kolibris und Pflanzen in den bearbeiteten Gebieten.相似文献
10.
Habitat destruction and the over-exploitation of species are perhaps thetwo most important processes threatening biodiversity. Whilst the growing humanpopulation puts considerable pressure on biological resources, a number ofsocial and economic factors tend to augment over-exploitation of theseresources. Here we show that the over-exploitation of the tropical palm treeEuterpe edulis Mart., as a consequence of social problems,has contributed significantly to its extinction in several forest fragments andalso to the disappearance of many wild animal species which used to be found inareas of the Atlantic Rain Forest (Brazil). Some of these species have been lostas a direct result of people hunting the animals when they went harvestingE. edulis while others disappeared as a consequence of thedecrease in food availability or by alterations in the trophic structure. 相似文献
11.
Habitat destruction and degradation are important drivers of biodiversity loss within agro-ecosystems. However, little is known about the effect of farming practices and the value of woody hedgerows on Lepidoptera in North America. The purpose of this work was to study moth diversity in woody hedgerows and croplands of organic and conventional farms. In addition, the influence of vegetation composition and abiotic variables on species richness, abundance, and composition was examined. Moths were sampled with light traps during six weeks in the summer of 2001. Vegetation data and abiotic variables were obtained for all sites. In total, 26,020 individuals from 12 families and 408 species were captured. Most species were uncommon. Only 35 species included >100 individuals while for 71% of species <10 individuals were found. The Noctuidae represented 221 species and 85% of all individuals captured. Woody hedgerows harbored more species and in greater number than croplands. There was no significant difference in moth diversity between organic and conventional farms, except that the Notodontidae were significantly more species rich in organic than in conventional sites. Results show that species richness, abundance, and composition were greatly influenced by habitat types (hedgerow versus crop field) and abiotic variables (minimum temperature which was correlated to moon illumination, rainfall, and cloud cover). Moth species composition was significantly correlated to vegetation composition. This study broadens our understanding of the factors driving moth diversity and expands our knowledge of their geographic range. The maintenance of noncrop habitats such as woody hedgerows within agro-ecosystems seems paramount to preserving the biodiversity and abundance of many organisms, including moths. 相似文献
12.
FÁBIO OLMOS 《Ibis》1997,139(4):685-691
Flocks of seabirds attending commercial bottom long-line fishing operations on the coastal shelf off southeastern Brazil show a greater species diversity during the summer than the winter (16 v 9 species), although the number of birds per flock tended to be greater during the cold season. During the summer, the Spectacled Petrel Procellaria aequinoctialis conspi-cillata was the commonest species, followed by the Great Shearwater Puffinus gravis, Cory's Shearwater Calonectris diomedea, skuas Stercorarius spp. and the Yellow-nosed Albatross Diomedea chlororhynchus. During the winter, the White-chinned Petrel Procellaria aequin-octialis, Yellow-nosed Albatross and Black-browed Albatross Diomedea melanophrys were jointly the commonest species. Marked differences in the relative abundance of species were observed between the different sampling periods, probably because of migratory movements but also because of seasonal shifts of the sea currents and the influence of cold fronts. Waters off southeastern Brazil are important feeding areas for some seabird populations nesting in the Tristan da Cunha and Gough group, especially for nonbreeding Spectacled Petrels and post-breeding Yellow-nosed Albatrosses. 相似文献
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14.
The large Saw-billed HermitRamphodon naevius and its foraging behaviour on a variety of ornithophilous flowers were studied at one site in the Atlantic rainforest in southeastern Brazil. The flower assemblage visited by this endemic hermit throughout the year is composed mainly by epiphytes and herbs, Bromeliaceae and Heliconiaceae being the staple foodplants. Most of the plant species present steady-state, long-tubed and high-reward flowers, and bloom sequentially. The Saw-billed Hermit is a year-round resident and traplining forager, behaves aggressively over its feeding routes, and excludes conspecifics and other hummingbird species from its main flower sources. This large hermit regularly visited and pollinated about 45 % of the native ornithophilous plants at the study site, thus acting as the major pollinator on this flower assemblage.
Zusammenfassung Der große in Südbrasilien endemische Sägeschnabel-Schattenkolibri (Ramphodon naevius) und dessen Nahrungsverhalten an ornithophilen Blüten einer Pflanzengesellschaft des atlantischen Regenwaldes wurde untersucht. Die von ihm besuchten Blüten gehören hauptsächlich zu Kräutern und Epiphyten, wobei Bromeliaceen und Heliconiaceen die Hauptnahrungspflanzen bilden. Diese Arten haben eine lange Blühperiode und blühen konsekutiv. Die Blüten besitzen lange Kronröhren und sondern reichlich Nektar ab. Der standortstreue Kolibri hält eine bestimmte Route und einen Zeitplan bei der Nahrungsaufnahme ein; er verhält sich aggressiv sowohl gegenüber Individuen seiner eigenen Art als auch solchen anderer Kolibriarten, die er von den wichtigsten Nahrungsquellen vertreibt. Der Sägeschnabel-Schattenkolibri besuchte regelmäßig ca. 45 % der ornithophilen einheimischen Pflanzen einer bestimmten Gesellschaft. Damit ist er der wichtigste Bestäuber dieser Pflanzen.相似文献
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16.
《Nordic Journal of Botany》2007,25(3-4):129-136
One of the largest genera of Orchidaceae with about 1125 species, Epidendrum L. presents several taxonomic problems, mainly due to the great variability of some of its species. The present study aims at evaluating the influence of different environments on the morphology of individuals from Epidendrum secundum , using morphometry to compare plants under cultivation and plants collected directly from the field. Eighty specimens maintained in cultivation at the Institute of Botany of São Paulo (Brazil) and 146 individuals originating from three natural populations, totaling 226 specimens, were analyzed with multivariate methods (PCA, CVA, DA). The fact that plants growing in rocky outcrops and plants from the Atlantic rainforest showed the largest morphological differentiation among themselves, indicates that phenotypes are strongly influenced by the habitat. Because plants collected from both habitats, maintained under cultivation for at least 20 years maintained their differentiation, such differentiation may have a genetic component. Because individuals collected in such environments present the largest morphological dimensions, new habitats generated by human activity, such as highway margins, seem to be quite favorable for these plants. 相似文献
17.
Cocoa (Theobroma cacao) is cultivated in the states of Bahia and Espírito Santo in eastern Brazil under the so-called cabruca system, where the understorey of native Atlantic forest is cleared and the canopy is thinned out to provide adequate shading for the cocoa trees. Apart from its economic and social role, the cabruca system is said to be important for the conservation of Atlantic forest biodiversity. In this paper we studied tree species richness and forest structure of cabrucas to examine the demographic health of these forests and discuss their long-term survival. Data were collected in 20 farms located alongside a 30km track of the northern margin of the Rio Doce, in northern Espírito Santo. All trees 5cm DBH were identified and their diameter was measured in 80 plots (600m2), totalling 4.8ha of sampled area. Recorded trees were also allocated to four different regeneration phases (pioneers, early secondary, late secondary and climax). The inventory resulted in 507 trees belonging to 105 species in 39 families. This species richness is much lower than in less disturbed forests located in the region. Pioneers and early secondary species dominate the cabruca forest in terms of number of species (56.2%), density (71.0%) and basal area (72.3%). The distribution of diameter frequency showed an imbalance in tree regeneration. Most trees in the range of 5–30cm DBH were pioneers (40.7%), or early secondary species (32.6%), while late secondary and climax trees were less frequent (10.2 and 16.5% of the sampled trees, respectively). The dominance of species of early regeneration phases was also observed for trees >30cm DBH (69.0% of pioneers or early secondary and 31.0% of late secondary or climax species). The results indicated that the cabruca forests are not only less diverse and less dense than secondary or primary forests of the region, but also, and more importantly, their natural succession and gap dynamics are being severely impaired. As a consequence, cabrucas present a structure where tree species of late successional phases are becoming increasingly rare while pioneers and early secondary species are becoming dominant. If current management practices of thinning and clearing of native trees are not improved, the long-term survival of these forests is questionable and their role in maintaining biodiversity in the long run is limited. 相似文献
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19.
Márcio Ayres J 《Trends in ecology & evolution》1986,1(2):48-49
There has been growing concern in Brazil for environmental issues in the last two decades. The conservation policies for Amazonia, which still represents the largest portion of forests of the country, are still based on isolated decisions made in the late 1970's. Among these policies there is, for instance, the plan for the establishment of a net of National Parks, proposed by Wetterberg et al. (1), based on the 'Pleistocene refugia' model. These refugia are areas of high species endemism, representing forest islands formed during the dry periods of the Pleistocene age, constituting the center of evolution and dispersal of Amazonian species (2). A number of parks and biological reserves have since been established and the decreese of laws protecting some elements of the fauna have been implemented. In 1979, studies for a more comprehensive plan for the conservation and development of Brazilian Amazonia were carried out in several institutions committed to research in Amazonia. As a result, several documents were handed to the government, but nothing has yet been implemented. Indeed, no environmental policy for Amazonia will succeed without an effective and comprehensive social plan, and the latter has yet to be formulated. 相似文献
20.
Field work and data from herbaria collections (2686 records) representing 283 taxa (265 species and 18 infraspecific taxa) of Bromeliaceae occurring at Minas Gerais state, southeastern Brazil, were analyzed in order to obtain distribution and diversity information, and to determine IUCN (The World Conservation Union) conservation status for each taxon. A map containing 1° × 1° grid cells was used to identify priority areas for new research collections, areas of high species diversity, and Bromeliaceae conservation status. A clear decrease in Bromeliaceae diversity is observed between the eastern and the western portions of Minas Gerais, and low floristic similarities were found between neighboring grid cells. The rocky mountains of Cadeia do Espinhaço are considered the most important area for Bromeliaceae endemics. From the 283 taxa of Bromeliaceae that occur at Minas Gerais, 118 (42%) are considered threatened, and 124 taxa (44% of the total) do not occur inside any protected area. The region of the Quadrilátero Ferrífero in the southern portion of the Cadeia do Espinhaço is the most threatened, and urgent strategies for conservation of this rich Bromeliaceae flora are needed. Northeastern Minas Gerais, particularly the rocky outcrops or inselbergs located in the Jequitinhonha and Mucuri rivers drainage basins need additional collection efforts and conservation actions focused on these saxicolous taxa. 相似文献