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1.
This study focuses on knowledge of medicinal plants among the Caiçaras (rural inhabitants of the Atlantic Forest coast, Brazil). In particular, we examine the use of medicinal plants according to sex and age to reveal general patterns of Caiçara knowledge and use of plant resources. Data collected through 449 interviews at 12 Caiçara communities (Rio de Janeiro and São Paulo coastal sites) include citations of 249 plants and identification of 227 species. We show the importance of introduced as opposed to native plants and of key individuals for the conservation of the Caiçaras-Atlantic Forest.  相似文献   

2.
In the UK, wood cricket (Nemobius sylvestris) is a ‘Species of Conservation Concern’, being restricted to only three areas in southern England. Little information is available on the specific habitat requirements of this species. In 2006, a field investigation within three woodlands on the Isle of Wight was undertaken to identify its habitat preferences. Factors positively influencing wood cricket presence within woodlands included the presence of a well-developed leaf litter layer, relatively low ground vegetation cover and height, low canopy cover and relatively short distances between individual populations. Regression models identified the degree of isolation and variables describing vegetation structure as the main predictors for wood cricket presence within woodland fragments. The results of this study indicate the preference of wood cricket for open wooded edges. Conservation efforts for this species should focus on continuation of regular management activities aimed at providing permanent open edge habitat within woodlands, to maintain viable populations.  相似文献   

3.
Size and age structure analysis, dated past disturbances, treefall replacement patterns, and spatial pattern analysis were used to reconstruct the developmental history of two old-growth Nothofagus fusca/N. menziesii stands, South Island, New Zealand. Diameter and height class distributions suggested that N. menziesii was replacing N. fusca, however, stand history reconstruction analysis showed that both species had regenerated intermittently after small-scale disturbances. Although large-scale disturbances such as blowdowns may occasionally generate even-aged stands, gap-phase regeneration maintains the forests in compositional equilibrium. In the absence of other competing tree species and understorey plants the two species appear to coexist by way of different life history strategies, where one species (N. menziesii) has low juvenile mortality and the other (N. fusca) has faster height growth rates and greater longevity and adult survivorship.  相似文献   

4.
The Brazilian rosewood (Dalbergia nigra) is an endangered tree endemic to the central Brazilian Atlantic Forest, one of the world''s most threatened biomes. The population diversity, phylogeographic structure and demographic history of this species were investigated using the variation in the chloroplast DNA (cpDNA) sequences of 185 individuals from 19 populations along the geographical range of the species. Fifteen haplotypes were detected in the analysis of 1297 bp from two non-coding sequences, trnV-trnM and trnL. We identified a strong genetic structure (FST=0.62, P<0.0001), with a latitudinal separation into three phylogeographic groups. The two northernmost groups showed evidence of having maintained historically larger populations than the southernmost group. Estimates of divergence times between these groups pointed to vicariance events in the Middle Pleistocene (ca. 350 000–780 000 years ago). The recurrence of past climatic changes in the central part of the Atlantic forest, with cycles of forest expansion and contraction, may have led to repeated vicariance events, resulting in the genetic differentiation of these groups. Based on comparisons among the populations of large reserves and small, disturbed fragments of the same phylogeographic group, we also found evidence of recent anthropogenic effects on genetic diversity. The results were also analysed with the aim of contributing to the conservation of D. nigra. We suggest that the three phylogeographic groups could be considered as three distinct management units. Based on the genetic diversity and uniqueness of the populations, we also indicate priority areas for conservation.  相似文献   

5.
The comparative phylogeographic study of the maned sloth (Bradypus torquatus) and the three-toed sloth (Bradypus variegatus) was performed using a segment of mitochondrial DNA (mtDNA) control region. We examined 19 B. torquatus from two regions and 47 B. variegatus from three distant regions of Atlantic forest. This first characterization of molecular diversity indicates a great diversity (B. torquatus: h = 0.901 ± 0.039 and π = 0.012 ± 0.007; B. variegatus: h = 0.699 ± 0.039 and π = 0.010 ± 0.006) and very divergent mitochondrial lineages within each sloth species. The different sampled regions carry distinct and non-overlapping sets of mtDNA haplotypes and are genetically divergent. This phylogeographic pattern may be characteristic of sloth species. In addition, we infer that two main phylogeographic groups exist in the Atlantic forest representing a north and south distinct divergence.  相似文献   

6.
Although the honey bee, Apis mellifera, has been considered the best pollinator for crops needing insect pollination, the current pandemic of varroatosis among honeybees highlights the need to find additional or alternative species as managed crop pollinators. Moreover, there is evidence that A. mellifera may not always be the most efficient pollinator. Introduction of A. mellifera into crops may be unnecessary, and even detrimental to non-Apis bee populations, which should be considered as an alternative for crop production improvement. Evaluating the pollination efficiency of non-Apis bees is one of the first steps in planning successful strategies for their conservation. In this study, we evaluated the pollination efficiency of Peponapis limitaris and A. mellifera in plots of Cucurbita moschata: pollen removal and deposition; pollinator visit frequency; and the pollinator visit–nectar production relationship. The results show P. limitaris to be the most efficient pollinator as: (1) both males and females remove and deposit almost four times as much pollen as A. mellifera; (2) they make significantly more floral visits than A. mellifera; and (3) their visit frequency shows a strong relationship to C. moschata nectar production during anthesis. Recommendations arising from this study are: (1) the introduction of A. mellifera be avoided in C. moschata crops; and (2) basic research be done on the biology of P. limitaris that contribute to its conservation and greater exploitation.  相似文献   

7.
Land-use intensification in Mediterranean agro-forest systems became a pressure on biodiversity, concerning particularly the woodland sensitive species. In 2001, the effects of a land-use gradient from old-growth cork-oak forest to a homogeneous agricultural area were assessed using rove beetles as indicators in a Mediterranean landscape. The aim was to find which species were negatively affected by land-use intensification at the landscape level and whether they benefited from cork-oak patches occurring along the land-use gradient. A total of 3,196 rove beetles from 88 taxa were sampled from all landscape types. Agricultural area recorded significantly higher numbers of abundance and species richness in relation to the cork-oak mosaics, i.e. the old-growth forest and the managed agro-forest landscapes (montados). Moreover, 70% of rove beetle indicator species common enough to be tested by IndVal displayed their highest indicator value for agriculture, showing a lower number of woodland indicators in comparison to ground beetles. Nevertheless, one rove beetle taxon was considered a specialist of closed woodland mosaics while no specialist ground beetle was found for that landscape typology. Some rare rove beetle species were also important in typifying diversity patterns of old-growth cork-oak forests. Hence, future management in Mediterranean landscapes should take into account not only indicator species common enough to be tested by IndVal, but also rare and endemic species. Considering the added value of cork-oak woodland cover for sensitive rove and ground beetle diversity, the strengthening of cork-oak woodland connectivity seems to be a crucial management that is required in agricultural Mediterranean landscapes.  相似文献   

8.
Zygaena viciae, the New Forest burnet moth, has only one population in Britain, in western Scotland. Here it was discovered in1963 and its population sustained itself, before declining seriously from 1980 to 1990. A survey in 1990 discovered at most 20 adult moths and it was clear that the site had become seriously over-grazed. A fence was erected to exclude sheep, with variable success until 1996, since when it has remained effective. Vegetation speedily changed from 1990 onwards, including re-establishment and spread of the main larval foodplant, Lathyrus pratensis. The moth population remained low until 1997, since which time it has dramatically increased, reaching an estimated 8500–10,200 in 2003. However, with only one site the moth remains threatened and establishment on new sites is now a priority.  相似文献   

9.
Tecophilaea cyanocrocus and Tulipasprengeri are both extinct in the wild as aresult of overharvesting by commercialcollectors. Stocks of both species survive incultivation in amateur collections, commercialnurseries and botanic garden collections.Whilst both species share a similarconservation history, the distribution ofgenetic diversity within cultivated materialwas unknown. To support the long-termconservation of both species the geneticdiversity of the surviving stocks was assessedusing amplified fragment length polymorphisms(AFLPs). This study revealed different geneticstructures for the two bulb species. The Kewcollections of T. cyanocrocus, originallyobtained from a commercial nursery, VanTubergen, are genetically highly uniform andthe addition of samples from other collectionshas dramatically increased the level ofvariation. In contrast, the collections ofT. sprengeri held at Kew since the early20th century include representativegenotypes covering the whole range of geneticvariation found in this species and areprobably the source of all other cultivatedmaterial. The results are discussed in relationto the management of these species to ensuretheir continued survival in cultivation.  相似文献   

10.
基于近年来分子系统学研究结果,石竹科无心菜属(Arenaria L.)齿瓣亚属[subgen.Odontostemma(G.Don)Williams]在属水平的地位得以恢复,该亚属中相关物种名也因此被组合至齿瓣无心菜属(Odontostemma Benth.ex G.Don)之中。然而,中国所产道孚无心菜(A.dawuensis A.J.LiQ.Ban)与神农架无心菜(A.shennongjiaensis Z.E.ZhaoZ.H.Shen)在相关处理中被遗漏,故在此给予其新的组合名称:O.dawuense(A.J.LiQ.Ban)G.Yao和O.shennongjiaense(Z.E.ZhaoZ.H.Shen)G.Yao。  相似文献   

11.
Two new species of hyalellid amphipods, Hyalella crawfordi and H. gauthieri, are described from Lake Titicaca; H. echinus (Faxon, 1876) is redescribed. The H. echinus group of species is newly proposed for these three species, and a group diagnosis is provided. A key to the three species in the group is provided Full article published online at http://www.senckenberg.de/odes/06-10.htm.  相似文献   

12.
Leposoma is a conspicuous component of leaf litter herpetofauna of South and Central American rainforests. The 15 bisexual and one parthenogenetic species are allocated to the parietale and scincoides groups based on morphology. Phylogenetic analyses of 1830 bp (mtDNA + nuclear) were performed on 63 specimens of four species from Amazonian and Panamanian rainforests, and six species and one undescribed form from the Atlantic Forest. Different methods of tree reconstruction were explored, with Anotosaura vanzolinia and Colobosauroides cearensis as outgroups. The monophyly of the parietale and scincoides groups is strongly supported. Contrary to previous hypotheses suggesting a recent contact between Atlantic and Amazon forests, our estimates point to an initial split in Miocene. The position of Leposoma baturitensis, endemic to relictual forests in the semiarid Caatingas northeastern Brazil, and its divergence from the remaining species of the Atlantic Forest, suggests an ancient isolation with no indication of a secondary contact with forests of the eastern coast. Our data do not permit unambiguous assignment of parental species of the unisexual Leposoma percarinatum or the mechanism involved in the origin of parthenogenesis, but revealed two highly divergent diploid and triploid lineages within L. percarinatum, indicating that the unisexuals represent a species complex.  相似文献   

13.
孙悦欣 《动物学杂志》2010,45(4):171-172
在整理采自辽宁省新宾县鼩鼱属(Sorex)标本时,发现小鼩鼱(S.inutus Linnaeus,1766)为辽宁省新纪录。主要特征为上颌第二单尖齿小于第一、三单尖齿,第五单尖齿小,约为第四单尖齿的2/3高。下颌门齿向前延伸甚长,其上切缘有3个深缺刻,犬齿小,是下前臼齿2/3高。  相似文献   

14.
Oaks host the richest fauna of saproxylic insect in Europe. We studied habitat preferences of two beetle families, Buprestidae and Cerambycidae, by rearing the beetles from standardised oak timber baits. Species density was higher in the understorey than in the canopy; and in sun-exposed baits if within the understorey. Insolation was the most important factor affecting the composition of reared assemblages (explaining ca. 30% of variation in the data), followed by vertical stratum (ca. 10%). Local dead wood volume had no effect. The high preference for sun-exposed wood located near the ground suggests that: (i) open-canopy woodlands had to be rather common in temperate Europe; (ii) oak-utilising xylophages would benefit from restoration of management practices such as coppicing or woodland pasture; (iii) the policy of increasing dead wood volume in commercial forests is principally correct, but its success will depend on dead wood location within the forests.  相似文献   

15.
Five species belonging to two genera of pinnotherid crabs are reported from the Yellow Sea. Two are new to science, namely: Sakaina glabra sp. nov. and Sakaina granulata sp. nov.; while three species are recorded for the first time from China: Pinnaxodes majorOrtmann, 1894, Pinnaxodes mutuensisSakai, 1939, and Sakaina japonicaSerène, 1964. Sakaina glabra can be easily distinguished from congeners by lacking a thick rim of pubescence along the anterolateral margin of the carapace. Sakaina granulata closely resembles S. asiatica (Sakai, 1933), but differs mainly in having a row of granule-like denticles along the anterolateral margin of its carapace.  相似文献   

16.
Since 1999, SPVS has been involved in three projects that combine two fundamental goals over the course of 40 years: the conservation of one of Brazil's most important remnants of Atlantic Forest and the implementation of projects for carbon sequestration. In addition, there is an interest in replicating these projects in order to restore other degraded areas, protect the Brazilian biomes, and help to diminish deforestation and forest fire, therefore reducing carbon emissions. The acquisition of 19,000 ha of degraded areas of high biological importance in southern Brazil was the first step towards the implementation of the projects. These areas are owned by SPVS, a Brazilian NGO, and are being restored, conserved and transformed into Private Natural Reserves, in partnership with the NGO – The Nature Conservancy, and financed by the companies – American Electric Power, General Motors and Chevron Texaco. The process of forest restoration involves several stages: soil studies, surveying the region's native plants, planning for restoration by means of a Geographical Information System, production of seedlings, application of different techniques for planting (such as manual or mechanised planting with seedlings and stakes), and biomass and biodiversity monitoring. To guarantee the survival of the seedlings on the planted areas, during the first three years, there is a continuous and systematic maintenance programme including weeding of undergrowth, crowing and organic fertilisation. The three projects already planted around 500,000 seedlings of native species until September 2004, and aim to plant a further 300,000 until 2008.  相似文献   

17.
To the 20 species and varieties of previously known in New Caledonia, there are here described and added three more species, one each in the sectionsBernardia, Lophostigma, andVeillonia.  相似文献   

18.
报道了中国四川报春花属(Primula L.)一新种——小繸瓣报春(P.hydrocotylifolia G.Hao,C.M.Hu&Y.Xu)。小繸瓣报春植株无毛、无粉,叶片多少呈圆形,具纤细的叶柄,开花期叶丛基部无鳞片,球形蒴果藏于宿存花萼,成熟时裂成不规则碎片,显然属于脆蒴报春组(sect.Petiolares Pax)革叶报春亚组(subsect.Chartacea W.W.Sm.&Forrest),并与该亚组的川西繸瓣报春(P.veitchiana Petitm.)最为接近,但后者植物体的各部分均远大于此新种,花序多花,花亦较大,二者之间无过渡类型。  相似文献   

19.
Balke  Michael 《Hydrobiologia》2001,464(1-3):107-112
Papuadessus pakdjoko n.gen., n.sp. is described from New Guinea. This species is well characterised by its coloration and the shape of the male genitalia. It is not yet possible to identify closer relatives of this species based on morphological evidence. The new species is a rheobiont, and only occurs at the edge of medium-sized to large rivers in gravelly and sandy substrates. Sites with mud or other finer substrates were unihabited by P. pakdjoko. It is concluded that this species could, therefore, be a good indicator to use in environmental impact assessments, especially where logging and large scale mining strongly increase the input of fine substrates to rivers.  相似文献   

20.
A central issue in socioecology is the nature of the relationship between an organism's environment and its social structure. In chimpanzees, the fission-fusion social system is thought to minimize feeding competition for primary dietary components: ephemeral, dispersed patches of ripe fruit. Intragroup feeding competition is thought to force individuals into small parties. Informal observations in the Sonso region of the Budongo forest had suggested that in this habitat, food supply was such that feeding competition was less important in determining grouping patterns than elsewhere. We used data collected on food supply and party sizes over a 4-year period to investigate this suggestion. In accord with theoretical expectation, sizes of foraging parties fluctuated with the size of food patches. However, party sizes showed either negative or no relationship with habitat-wide measures of food abundance. Likewise party sizes showed little relationship to overall measures of food dispersion. For important dietary items, both fruit and leaves had patchy distributions, though the degree of clumping was not strong, and fruit was not more clumped than leaves. Generally, abundant food appeared to be less patchy, and chimpanzees appeared to use more patches as food became more abundant rather than forming larger parties. We suggest that both dispersal and abundance need to be considered when investigating the impact of food supply on grouping patterns, and that the importance of food as a factor in determining chimpanzee grouping patterns declines with increasing levels of abundance.  相似文献   

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