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1.
Ian J. Kitching 《Biodiversity and Conservation》1996,5(7):841-858
Setting priorities in biodiversity conservation requires that explicit, efficient and appropriate methods are developed and made available to conservation managers. The principle of complementarity is fundamental to the most efficient of these methods. Given a goal of only a single representation of each taxon, complementarity analysis of data sets of owls, hawkmoths and tiger beetles in Thailand yields near-minimum sets of 6, 14 and 34 areas, respectively. The consensus of these sets comprises 48 areas. However, when the data are combined into a single data set, complementarity analysis gives a more efficient solution of 46 areas. Over 90% of the owls, hawkmoths and tiger beetles are already represented as a minimum of one population within the current protected areas network of Thailand. However, an additional 18 areas are still required for complete representation. Several of these additional areas are discussed and their potential contribution to biodiversity conservation in Thailand examined. Khao Pok Yo and Doi Pa Hom Pok are noted as being of particular importance. The case of Sanpatong emphasizes the need to remain aware of the biology and ecology of the species under study. 相似文献
2.
Lantoniaina Andriamampianina Claire Kremen Dick Vane-Wright David Lees Vincent Razafimahatratra 《Journal of Insect Conservation》2000,4(2):109-128
Distributional ranges of 17 genera and 172 species of Malagasy tiger beetles (Coleoptera, Cicindelidae) have been compiled to determine patterns of species richness and endemism. These patterns reveal large sampling gaps, and potential priority areas for conservation action. Northern and south-western parts of the island are richer in genera, whereas eastern and especially northern parts of the rainforest show higher species richness, due to extensive radiations within the genera Pogonostoma and Physodeutera. A set of 23 areas are identified in this study as priority foci for tiger beetle conservation, and six general regions are bioinventory priorities. 相似文献
3.
Jon C. Lovett Stephen Rudd James Taplin Christian Frimodt-Møller 《Biodiversity and Conservation》2000,9(1):37-46
Plant species richness and range-size rarity in Africa south of the Sahara is concentrated in centres of plant diversity and endemism. Distribution patterns of plants mapped in the Distributiones Plantarum Africanum series and selected taxonomic monographs are analysed using the computer programme WORLDMAP. The plants are divided into four groups: herbaceous geophytes, mesophytic herbs, light-demanding shrubs and woody genera. Each group has peaks of species richness and range-size rarity at locations different to the other groups. Herbaceous geophytes and mesophytic herbs have their peaks of species richness and range-size rarity in the same location, the western Cape for geophytes and the Crystal Mountain for mesophytic herbs, whereas light-demanding shrubs and woody genera have peaks in different places. The results are discussed in relation to possible factors determining species richness and endemism and their likely conservation significance. 相似文献
4.
Alan W. Meerow Carl Lewis Ramona Oviedo Javier Francisco‐Ortega 《Plant Species Biology》2014,29(1):2-15
Ipomoea microdactyla Griseb. (Convolvulaceae) is restricted to the Bahamian archipelago, Cuba, and southeastern Florida. The species is listed as a state endangered species in Florida, where it is mostly restricted to the hyperfragmented pine rockland of Miami‐Dade County. Using seven DNA microsatellite loci, we assessed levels of genetic diversity for 12 populations of this species from Andros Island in the Bahamas (six sites), Cuba (one site), and Florida (five sites). We found significantly greater mean numbers of alleles, and higher mean values for both observed and expected heterozygosity in populations from the continuous forest on Andros than those from the habitat fragments in Florida. It is unknown if these patterns of genetic diversity in the Florida populations are the result of habitat fragmentation or founder effects. The population from Cuba exhibited relatively high levels of genetic variation, suggesting that this island is a major center of diversity and dispersal for this species. It appears that hybrid introgression for I. carolina alleles within I. microdactyla individuals occurred at a single site on Andros Island. Overall, the mean inbreeding coefficient value was 0.089, suggesting low levels of inbreeding. The highest inbreeding coefficient values were mostly recorded in Florida. Two groups were revealed, one containing the populations from Florida, and the second one encompassing those from the Bahamas and Cuba. Our results highlight the negative genetic consequences of habitat fragmentation and support initiatives recently established to establish corridors to connect the remnants of the pine forest of the Miami‐Dade County. 相似文献
5.
Drift collections of pupal exuviae from 2nd–5th order streams of the Guanacaste National Park in Northwest Costa Rica and from 3rd–6th order streams of the West African countries of Guinea, Ivory Coast, Sierra Leone and Togo have revealed high community (alpha) and regional (beta) levels of species diversity.Samples have been processed from 13 streams of the Guanacaste N. P. including two, Quebrada Las Yeguitas (2 stations) and Rio Tempisquito, for which year-long series were available. A total of 266 species level taxa have been recognized from these streams and are distributed over the higher taxa as follows: Chironomini-73, Pseudochironomini-4, Tanytarsini-55, Orthocladiinae-92, Macropelopiini-5 and Pentaneurini-37. The two sites on the Q. Las Yeguitas have a combined total of 216 species, and together with R. Tempisquito a total of 238 species. The single richest sample (Q. Las Yeguitas, Orosi station, 1990-Jan.-9) contained 102 species.Samples have been processed from 31 West African Streams which, for the most part, are represented by single samples. A total of 299 species level taxa have been recognized from these streams which are distributed over the higher taxa as follows: Chrinomini-139, Tanytarsini-62, Orthocladiinae-56, Coelotanypodini-2, Macropelopiini-3 and Pentaneurini-37. The single largest collection, containing 175 species, was taken from the Upper Dion River, a 6th order stream in the Upper Niger basin of the Guinean highlands.The compositions of the two regional faunas show similarities in two general features: they are both taxonomically narrow (few subfamilies and tribes) and taxonomically deep (many closely related genera, often with a relatively large number of closely related species). The high alpha diversity values require an ecological explanation, most probably along the axes of resources (time, space and food). The high regional diversities require an historical explanation. It is proposed that great climatic variation during the Pleistocene coupled with great geographic alteration of the connection between North and South America may be responsible for both the taxonomic narrowness and depth seen in the chironomid faunas of West Africa and Costa Rica. 相似文献
6.
Ronald Sluys 《Biodiversity and Conservation》1999,8(12):1663-1681
Biodiversity conservation requires prioritization of areas for in situ conservation. In that perspective, the present study documents the global diversity of a component of the soil macrofauna, the land planarians, and concerns an exploratory analysis of their possible role as indicators of biodiversity. Diversity is described by three quantitative methods: (1) hotspots of species richness, selecting areas richest in species, (2) hotspots of range-size rarity, identifying areas richest in narrowly endemic species, and (3) complementarity, prioritizing areas according to their greatest combined species richness. The biodiversity measures of species richness and range-size rarity show a great correspondence in the identification of hotspots of diversity; both measures identify the following seven areas as the most biodiverse for land planarians: Sao Paulo, Florianopolis, western Java, Tasmania, Sri Lanka, North Island/New Zealand, and Sydney. It is discussed to what extent the results for the land planarians correspond with those obtained in other studies that assessed biodiversity hotspots for taxa on a global scale. It is noteworthy that land planarians identify a few global hotspots of diversity that generally do not feature, or only have low rankings, in other studies: New Zealand, southeastern Australia, and Tasmania. 相似文献
7.
Seventy-two cladoceran species from southern Thailand include eleven first records. Species accumulation curves were used to estimate the total number of species present, and Chaos estimator was used to extrapolate the species number observed in 212 samples to the total number present. This S*max amounted to 76.06 species, with a low ratio of variance/estimator. Cladoceran faunas were compared by a complementarity index at three levels: between habitat types, between different zones of Thailand, and between Thailand and other countries. The geographical gradient was quite strong, but because not all areas have been studied to the same degree and with the same taxonomic accuracy, some comparisons are robust while others are not. 相似文献
8.
In central Japan, Aokigahara woodland is considered to be one of the most natural areas around Mount Fuji and a core area in the conservation of the biodiversity of Mount Fuji. We chose butterflies as an indicator species of biodiversity and examined six communities in and around the woodland in 2000 using transect counts to examine and search for diversity and rarity hotspots and their associated landscapes. The results showed that butterfly species richness and species diversities H 1/ were significantly higher in forest-edge sites than in forest-interior and/or open-land sites, and variation in the total number of species among these three landscape types was well accounted for by ecologically specialist species, such as landscape specifics, oligovoltines, narrow diet feeders and low-density species. Thus, the species regarded as vulnerable to extinction, including Red List species, were observed more often in forest-edge sites than in forest-interior and/or open-land sites. As a result, in the study area, diversity and rarity hotspots were found in forest-edge landscapes. The reasons why butterfly diversity and rarity hotspots were established in forest-edge landscapes were analyzed and interpreted from several points of view, including disturbance level, landscape elements and plant species richness. From these results, and the fact that some species were confined to forest-interior sites, we conclude that it is very important to conserve and manage forest-edge habitats (considered to be semi-natural) as well as forest-interior habitats (considered to be the most natural) to maintain the diversity of butterfly communities and preserve the various types of threatened species in and around the Aokigahara woodland. 相似文献
9.
Mexico is considered a megadiverse country containing more than 10% of the world's biodiversity. The distribution of this species richness and endemism is different among the different Mexican states. We examined the species richness patterns of 13 families of vascular plants (including ferns, gymnosperms and angiosperms) in Mexico using political divisions (states) as units of analysis. We analysed the species richness values (absolute richness, endemic richness and restrictive richness) of these plant families using stepwise multiple regression analysis, assessing their relationship with a set of 10 environmental variables (expressed as heterogeneity coefficients). A combined cluster analysis with multidimensional scaling analysis (MDS) and an analysis of similarities were also undertaken to define the spatial–geographical patterns. Additionally, we proposed a methodological strategy to determine which states of Mexico have priorities for conservation. Our results suggested that the three species richness values used were significantly predicted by environmental factors, especially by climatic heterogeneity. Notwithstanding that a linear pattern was recognized, the Mexican states were gathered in four groups, which were confirmed by the MDS and the cluster analysis: (1) the Yucatan Peninsula, (2) arid Mexico, (3) the Mexican Transition Zone and (4) the megadiverse states. We proposed that 12 Mexican states include all the environmental conditions and are candidates for developing conservation programmes: (1) Quintana Roo, Tabasco and Yucatán, (2) Baja California, Chihuahua and Sinaloa, (3) Guerrero, Jalisco and Nuevo León and (4) Chiapas, Oaxaca and Veracruz. 相似文献
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11.
Nadja Lepsch-Cunha Paulo Y. Kageyama Roland Vencovsky 《Biodiversity and Conservation》1999,8(9):1205-1218
We quantified the within-population genetic variation of Couratari multiflora and C. guianensis, two tree species found in terra firme forests of central Amazonia. Both species have some ecological features in common, but they differ in population abundance across their geographic ranges. While C. multiflora has been found only in low-density populations in all sites studied to date, C. guianensis is relatively common in some sites and very scarce in others. In a 400-ha plot, we found 41 and 29 adults of C. multiflora and C. guianensis, respectively. Twenty-two saplings of C. guianensis and 103 seedlings of C. multiflora were also examined. The mean expected heterozygosities (Hem) of seedlings and adults of C. multiflora were 0.431 and 0.436, and the mean fixation indices (Fm), 0.114 and 0.176, respectively. For C. guianensis, saplings and adults presented Hem equal to 0.425 and 0.429, and the Fm were 0.393 and 0.527, respectively. These low-density populations of two congeneric species did not differ in terms of genetic diversity, but rather they differed in terms of mean observed heterozygosity (Hom), and therefore Fm. The species with variable population density had lower Hom and greater Fm relative to the species that is always found in low-density. 相似文献
12.
Annik Schnitzler 《Biodiversity and Conservation》1996,5(6):743-758
Traditional measures of biotic indices (, , ) from phytosociological relevés are used to compare diversity at three scale-levels in the upper Rhine valley (Alsace, northeastern region) and the middle Loire (Bourgogne, central region), France. Both study areas included a tributary. The Ill, which is the Rhine tributary in this sector, has no forest communities in common with the main river because of opposite hydrological and edaphic characteristics. This is not the case in the Loire valley, in which the fluvial characteristics are close to those of its tributary, the Allier.Nearly all forest communities (12/14) were shown to be species-rich, due to the role of natural disturbances. Species richness peaks in late-successional forests of the Rhine valley (for example, up to 50 woody species in Querco-Ulmetum). Sixty per cent of the forest-communities are comon to the two floodplains, which explains why 85% of the families, 65% of the genera and 55% of the species are in common. Compared to the Loire valley, the Rhine valleys shows higher biotic diversity. This was related first to its geographical situation, and second to higher landscape heterogeneity. Human disturbance through river management is responsible for changes in species composition as shown by floristic comparison of flooded and unflooded sites. Insularity of natural forests among man-made landscapes is involved in species diversity. In order to preserve the natural diversity of such rich landscapes, floodable areas should be recreated and the attitudes of foresters should evolve accordingly. 相似文献
13.
Besma Haffaressas Sihem Djellab Farrah Samraoui Ahmed H Alfarhan Francis Gilbert Antonio Ricarte 《法国昆虫学会纪事》2013,49(5):324-333
A survey of the hoverflies (Diptera: Syrphidae) of the region of Guelma, northeast Algeria, was carried out from August 2011 to July 2013. A total of 31 species was recorded with six (Scaeva mecogramma, Epistrophe melanostoma, Syrphus vitripennis, Brachypalpus valgus, Merodon calcaratus and M. chalybeus) new to Algeria. Of these, three species (E. melanostoma, M. calcaratus and M. chalybeus) are also new additions to the entomofauna of North Africa. The results complement those of a previous study covering Numidia and Tebessa and provide a more comprehensive view of the phenology and distribution of Syrphidae across northeast Algeria. An improved knowledge of the distribution of North African hoverflies will contribute to a better assessment of the status of each taxon and inform conservation efforts. 相似文献
14.
We examined diversity, community composition, and wing-state of Carabidae as a function of forest age in Piedmont North Carolina. Carabidae were collected monthly from 396 pitfall traps (12×33 sites) from March 2009 through February 2010, representing 5 forest age classes approximately 0, 10, 50, 85, and 150 years old. A total of 2,568 individuals, representing 30 genera and 63 species, were collected. Carabid species diversity, as estimated by six diversity indices, was significantly different between the oldest and youngest forest age classes for four of the six indices. Most carabid species were habitat generalists, occurring in all or most of the forest age classes. Carabid species composition varied across forest age classes. Seventeen carabid species were identified as potential candidates for ecological indicators of forest age. Non-metric multidimensional scaling (NMDS) showed separation among forest age classes in terms of carabid beetle community composition. The proportion of individuals capable of flight decreased significantly with forest age. 相似文献
15.
To enable use of Empididae s.l. (Diptera) as a tool in nature conservation, a Red Data Book of this taxonomical group was generated for Flanders, Belgium. All distribution data on species in Belgium between 1887 and 1999 were gathered from collections as well as personal sampling efforts by the first two authors. This resulted in about 21,000 records of Empididae, Hybotidae, Microphoridae and Atelestidae with 16,119 records for Flanders (northern Belgium) and 4776 for Wallony (southern Belgium). All species were assigned to Red Data Book categories which are based on a combination of a rarity and a trend criterion. Rarity is expressed as the proportion of the total number of UTM 5km squares sampled in which the species have been found since 1981. The trend criterion is interpreted as the change of the species rarity between 1887–1980 and 1981–1999. A comparable number of UTM 5km squares was investigated during the two time periods. A total of 259 species were recorded in Flanders. Twenty-seven or 10% of them are considered as 'extinct in Flanders', 10 (4%) as 'critically endangered', 12 (5%) as 'endangered', 11 (4%) as 'vulnerable', 99 species (38%) as 'susceptible' or 'rare', 65 species (25%) as 'safe' or 'at low risk' and 34 species (13%) are assigned to the category 'data deficient' due to taxonomic problems or a lack of ecological data. Only one of the common species shows a recent decrease of more than 50% and is classified as 'nearly threatened'. Current threats in most species are related to the alteration or destruction of their favoured habitats. The results are discussed in the light of recent criticism of the use of Red Data Books in nature conservation. 相似文献
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17.
Guidugli MC Accoroni KA Mestriner MA Contel EP Martinez CA Alzate-Marin AL 《Genetics and molecular biology》2010,33(1):131-134
Twelve microsatellite loci previously developed in the tropical tree Cariniana estrellensis were genetically characterized in Cariniana legalis. Polymorphisms were assessed in 28 C. legalis individuals found between the Pardo and Mogi-Guaçu River basins in the state of São Paulo, Brazil. Of the 12 loci, 10 were polymorphic and exhibited Mendelian inheritance. The allelic richness at each locus ranged from 2-11, with an average of 7 alleles per locus, and the expected heterozygosity ranged from 0.07-0.88. These loci showed a high probability of paternity exclusion. The characteristics of these heterologous microsatellite markers indicate that they are suitable tools for investigating questions concerning population genetics in C. legalis. 相似文献
18.
The freshwater crabs of the Neotropics comprise 311 species in two families (Pseudothelphusidae and Trichodactylidae) and one or both of these families are found in all of the countries in the Neotropical region (except for Chile and some of the Caribbean islands). Colombia (102 species, 81% endemic) and Mexico (67 species, 95% endemic) are the biodiversity hotspots of freshwater crab species richness and country-level endemism for this region. The results of the IUCN Red List conservation assessments show that 34% of pseudothelphusids and 10% of trichodactylids have an elevated risk of extinction, 29% of pseudothelphusids and 75% of trichodactylids are not at-risk (Least Concern), and although none are actually extinct, 56% of pseudothelphusids and 17% of trichodactylids are too poorly known to assess (Data Deficient). Colombia (14 species), Venezuela (7 species), Mexico (6 species), and Ecuador (5 species) are the countries with the highest number of threatened species of Neotropical freshwater crabs. The majority of threatened species are restricted-range semiterrestrial endemics living in habitats subjected to deforestation, alteration of drainage patterns, and pollution. This underlines the need to prioritize and develop conservation measures before species decline to levels from which they cannot recover. These results represent a baseline that can be used to design strategies to save threatened Neotropical species of freshwater crabs. 相似文献
19.
P. Löwenberg‐Neto C. J. B. De Carvalho J. A. F. Diniz‐Filho 《Journal of Zoological Systematics and Evolutionary Research》2008,46(4):374-380
Considering that Earth and life evolve together, the present study aims to verify whether the species richness patterns are spatially congruent to biotic history. Niche conservatism was adopted as a background hypothesis to associate species richness with phylogenetic information. A parallel analysis between this procedure and cladistic biogeography was undertaken. Eleven Muscidae genera that were previously systematically reviewed for phylogenetic hypotheses were chosen for the analysis. The genera were split into ‘basal’ and ‘derived’ species, following terminal taxon root distance within each genus. Richness patterns were contrasted for the most basal and most derived 33% of species, and richness maps were constructed at 220 × 220 km grid size. A difference richness map was drawn by derived minus basal values (=derived?basal). For regions with difference values around zero, a component analysis was performed and compared with relationships established by other studies. Derived and basal species richness showed a very concise richness gradient in the Neotropical region and it was compatible with its known biogeographical history. In the Andean region, richness did not show any pattern. The area cladogram grouped Subantarctic subregion in a polytomy and Central Chile as a paraphyletic group. All hypotheses about area relationship were divergent and no vicariant pattern could be recognized in Andean region. In Neotropical region, Muscidae results corroborated a previous component relationship. The hypothesis that Paleogene climatic changes could drive the biotic component’s split was suggested. In the Andean region, recently ice sheet covering events had driven the species to disperse and/or extinct resulted in absence of pattern seen either in richness analysis or in component analysis. It is believed that species richness is linked to biotic history and this fact may be considered when evaluating hypotheses to explain broad‐scale richness gradients. 相似文献
20.
ANNA C. D. R. BARBOSA THAÍS C. CORRÊA FELIPE GALZERANI PEDRO M. GALETTI TERUMI HATANAKA 《Molecular ecology resources》2006,6(3):936-938
Prochilodus species inhabit the main river systems of South America and usually present commercial value to inland fishing. In the present study, we describe the isolation and characterization of 13 novel microsatellite loci in Prochilodus argenteus. The number of alleles per polymorphic locus varied from four to 22 and the observed heterozygosity ranged from 0.333 to 0.893. Additionally, cross‐species amplification was successful in two other Prochilodus species. These loci will be useful for studies of the population genetic structure in this fish group. 相似文献