71 research outputs found
Plant biodiversity drivers in Brazilian campos rupestres : insights from phylogenetic structure
MMwas funded by the São Paulo Research Foundation (FAPESP 2013/15280–9) at the initial stages of this work.Old, climate-buffered infertile landscapes (Ocbils) have attracted increasing levels of interest in recent years because of their exceptionally diverse plant communities. Brazil’s campos rupestres (rupestrian grasslands) are home to almost 15% of Brazil’s native flora in less than 0.8% of Brazil’s territory: an ideal study system for exploring variation in floristic diversity and phylogenetic structure in sites differing in geology and phytophysiognomy. We found significant differences in floristic diversity and phylogenetic structure across a range of study sites encompassing open vegetation and forest on quartzite and on ironstone substrates, commonly termed canga. Substrate was key in structuring floristic diversity with physiognomy having a secondary effect. In contrast physiognomy was more important than substrate in structuring phylogenetic diversity, with neither substrate nor its interaction with physiognomy accounting for significant variation in phylogenetic structure. Phylogenetic clustering was significant in open vegetation on both canga and quartzite, reflecting the potential role of environmental filtering in these exposed montane communities adapted to multiple environmental stressors. In forest communities, phylogenetic clustering was significant only at relatively deep nodes of the phylogeny in forest on quartzite while no significant phylogenetic clustering was detected across forest on canga, which may be attributable to proximity to the megadiverse Atlantic forest biome and/or comparatively benign environmental conditions in forest on canga with relatively deep, nutrient-rich soils and access to edaphic water reliable in comparison to those for open vegetation on canga and open or forest communities on quartzite. Clades representing relatively old lineages are significantly over-represented in campos rupestres on quartzite, consistent with the Gondwanan Heritage Hypothesis of Ocbil theory. In contrast, forested sites on canga are recognized as Yodfels. To be effective, conservation measures must take account of the distinct communities which are encompassed within the broad term campos rupestres, and the differing vulnerabilities of Ocbils and Yodfels.Publisher PDFPeer reviewe
Flora da Serra do Cipó, Minas Gerais: Rubiaceae
O estudo da família Rubiaceae é parte do levantamento da "Flora da Serra do Cipó, Minas Gerais, Brasil". Esta família é representada na área por 36 gêneros, totalizando 91 espécies. Uma nova espécie de Psyllocarpus é descrita e ilustrada. São apresentadas chave para gêneros e espécies, descrições e ilustrações, além de comentários sobre a distribuição geográfica e hábitat das espécies
Utilização de cactáceas por sertanejos baianos. Tipos conexivos para definir categorias utilitárias
The use of cacti is one of the most important connections between humans and plants in the dryland region of Brazil, where they are used as food, medicines and in horticulture, amongst many other purposes. There is presently very little knowledge of this connection available in a systematic and synthetic form. Therefore, the present study aims to evaluate the literature by using a field study in five municipals in the state of Bahia: Valente, Queimadas, Santaluz, São Domingos and Canudos. Informal and semi-structured interviews were carried out with 32 local people. The interviews were tape-recorded and transcribed verbatim. The sample was defined after meeting the possible interviewees ad libitum, causing the increase of information to flow in a ‘snow-ball’ progression. This method allowed us to reach a level of exhaustive sampling through progressive inclusion of information. The cactus material collected was determined by specialists and detosited at HUEFS herbarium. The ten species identified as used locally by the ‘informants’ were determined as: Cereus jamacaru DC., Harrisia adscendens (Guerke) Britton & Rose, Melocactus salvadorensis Werdermann, Nopalea cochenillifera (L.) Salm-Dyck, Opuntia dillenii (Ker-Gawler) Haworth, Opuntia ficus-indica (L.) Miller Opuntia palmadora Britton & Rose, Pilosocereus catingicola (Guerke) Byles & Rowley, Pilosocereus gounellei (Weber) Byles & Rowley, Pilosocereus tuberculatus (Werdermann) Byles & Rowley. The analysis of the diverse uses allowed us to include them in eight of the connective types proposed by Marques: ludic, medical, mystic, economic, esthetic, domestic, erotic and trophic. The medical and trophic connections can be subdivided into direct and indirect sub-types. The use categories with largest number of species were trophic indirect [N= 10] and direct [N= 6], and medical direct [N= 7]. Connections with strong, permanent status were present [e.g. use as hedges - connection of domestic type; as ornamental plants - connection of esthetic type; commercialization - economic connection; ‘white sorcery’ - mystic type; as medicine - medical type] as weak, residual ones [domestic connection related to manufacture of doors, windows and other parts of the house]. Some of the data obtained through this research agree with information found in literature, however, many of the uses registered here are original, and point towards new perspectives for the evaluation of the adaptations of the rural population in the Brazilian dryland.Dentre as conexões seres humanos/vegetal no Semi-árido, destaca-se a conexão de múltiplo uso com cactáceas, incluindo-as como recursos alimentares, medicinais, ornamentais etc. Não existindo conhecimento abrangente que esteja sinteticamente sistematizado, este trabalho teve por objetivo avaliar criticamente a literatura disponível, com base em um estudo etnobotânico de campo realizado em cinco municípios do Semi-árido baiano: Valente, Queimadas, Santaluz, São Domingos e Canudos. Foram feitas entrevistas informais e semi-estruturadas com 32 moradores locais. Seus depoimentos foram registrados em fitas magnéticas e transcritos verbatim. A amostra foi definida a partir de encontros ad libitum que permitiram um acréscimo por progressão em bola de neve e a amostragem foi considerada suficiente com base no efeito de uma inclusão progressiva que permitiu aplicar o critério de exaustividade. O material botânico foi herborizado in loco, identificado por especialista e depositado no herbário HUEFS. Foram identificadas taxonomicamente dez espécies, as quais, segundo os informantes, têm utilização local: Cereus jamacaru DC., Harrisia adscendens (Guerke) Britton & Rose, Melocactus salvadorensis Werdermann, Nopalea cochenillifera (L.) Salm-Dyck, Opuntia dillenii (Ker-Gawler) Haworth, Opuntia ficus-indica (L.) Miller, Opuntia palmadora Britton & Rose, Pilosocereus catingicola (Guerke) Byles & Rowley, Pilosocereus gounellei (Weber) Byles & Rowley, Pilosocereus tuberculatus (Werdermann) Byles & Rowley. A análise das diversas utilizações permitiu enquadrá-las em oito dos tipos conexivos propostos por Marques: lúdico, médico, místico, econômico, estético, doméstico, erótico e trófico. As conexões do tipo médico e trófico são enquadráveis nos subtipos direto e indireto. As categorias de uso que incluíram o maior número de espécies identificadas foram as correspondentes aos tipos conexivos trófico indireto (n= 10) e direto (n= 6) e médico direto (n= 7). Foram detectadas tanto conexões com status de permanência forte (e.g., feitura de cercas vivas - conexão do tipo doméstico; ornamentação - conexão do tipo estético; comercialização - conexão do tipo econômico; “simpatia” - conexão do tipo místico; preparo de remédios – conexão do tipo médico) quanto com status de residuárias fracas (e.g., a conexão do tipo doméstico para feitura de portas, janelas, ripas e caibros). Embora alguns dados obtidos estejam de acordo com o já relatado na literatura, muitos deles são originais, o que abre novas perspectivas para uma avaliação adaptativa das populações rurais do Semi-árido
Cactaceae no Parque Estadual do Ibitipoca, Minas Gerais, Brasil
O Parque Estadual do Ibitipoca está localizado no sudeste de Minas Gerais, entre os municípios de Lima Duarte, Santa Rita de Ibitipoca e Bias Fortes (21º40’-21º44’S e 43º52’-43º55’W). Compreende uma área de 1.488 ha, com altitudes entre 1100 e 1748 m.s.m., e vegetação com predominância de campos rupestres. O objetivo do presente estudo foi realizar um levantamento de Cactaceae no PEIB. A família está representada na área por quatro gêneros e sete espécies, listados a seguir: Arthrocereus melanurus subsp. magnus, Hatiora salicornioides, Rhipsalis elliptica, Rhipsalis floccosa subsp. pulvinigera, R. juengeri, R. pulchra e Schlumbergera opuntioides. São apresentadas chave de identificação, descrições, ilustrações, comentários taxonômicos e ecológicos para as espécies
Distribución y conservación de Cactaceae en Bosques Tropicales Estacionalmente Secos: apreciaciones a partir de estudios florísticos y fitosociológicos
Species lists available from floristic and phytosociological studies contain important information about species distributions that are useful for making biogeographical inferences and even to evaluate conservation status of species and ecosystems. In the case of the Caatinga, this information may contribute to challenging the pre-established idea that it is a homogeneous vegetation unit. The strong relation between the substrate and the plant assemblages of the Caatinga may characterise different types of vegetation. In this way, the objective of the present study is to evaluate whether differences in the distribution of Cactaceae relate to distinctive types of substrate (sedimentary and crystalline) as much in terms of floristic richness as species density. Concomitantly, we evaluated the conservation status of the Caatinga areas studied. To obtain the data, we undertook a bibliographic revision of floristic and phytosociological studies in the Caatinga and constructed a similarity matrix using the selected floristic studies in order to evaluate the relation among different areas of Caatinga. We found that 48 areas included Cactaceae species; 33 species distributed in 14 genera were recorded. Among these taxa, Cereus jamacaru was the species that presented the largest number of occurrences, appearing in 17 areas, followed by Pilosocereus gounellei (=Xiquexique gounellei), found in 11 studies, and Tacinga inamoena in 10. The grouping analysis resulted in the formation of 10 groups, with a remarkable relationship between species and soil type. There were differences in both the diversity and density of species related with the degree of conservation of the Caatinga, noticeable from the direct relationship between conservation and richness and, indirectly, between density and number of species.Las listas de especies presentadas en trabajos florísticos o fitosociológicos proporcionan importante información sobre distribución, útil para realizar inferencias biogeográficas y evaluar el estado de conservación de especies o incluso de ecosistemas. En el caso de los bosques secos del nordeste de Brasil, conocidos como Caatinga, el análisis de esas listas puede contribuir para confrontar ideas previamente establecidas sobre la homogeneidad de esa unidad de vegetación. La fuerte relación entre el sustrato y los ensambles de plantas de la Caatinga pueden caracterizar distintos tipos de vegetación. Es así como, el objetivo de este trabajo es evaluar sí la distribución de Cactaceae está relacionada con los tipos de sustrato (sedimentar y cristalino), sea con la riqueza florística o la densidad de las especies. Al mismo tiempo, evaluamos el estado de conservación de las áreas estudiadas de la Caatinga. Los datos fueron obtenidos a partir de revisiones bibliográficas, de estudios de florística y fitosociología en la Caatinga. Para evaluar las distintas áreas, con los estudios florísticos seleccionados se preparó una matriz de similaridad. Se encontró que, 48 áreas tenían especies de Cactaceae; 33 especies distribuidas en 14 géneros fueron listadas. Cereus jamacaru fue la especie con el mayor número de puntos en 17 áreas, seguido por Pilosocereus gounellei (=Xiquexique gounellei), encontrado en 11 estudios y Tacinga inamoena, en 10. El análisis resultó en la formación de 10 grupos con fuertes relaciones entre especies y tipos de sustratos. También, encontramos diferencias en diversidad de especies en relación con el estado de conservación de la Caatinga, notable por las relaciones directas entre conservación y riqueza de especies, e indirectas entre densidad y número de especies
On the true identity of Mendoncia “stellate” trichomes
ABSTRACT The present survey of leaf-blade trichomes of Mendoncia used SEM and light microscopy to investigate the diversity of trichome types in Neotropical and Paleotropical species of the genus. The eglandular trichomes are filiform, uniseriate, with asymmetric epidermal cells arranged radially around the trichome, these epidermal cells may be short or elongated, oriented in two groups. These cells, when elongated, are covered with epicuticular wax, forming smooth thick plates. African species have dendritic but not stellate trichomes. Character states such as number and length of basal cells were shown to overlap within the same species and therefore their use in isolation is not recommended for subgeneric classification of Mendoncia. Neotropical Mendoncia trichomes with well-developed epidermal cells arranged radially around the trichome appear to be unique to this group, without parallel in other plant families
Plotting a future for Amazonian canga vegetation in a campo rupestre context
This work was supported by CNPq project (455505/2014-4) to all authors; The MPEG/ITVDS/FADESP Term of Agreement (01205.000250/2014-10); DCZ – CNPq productivity grant; NFOM - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (BR- 88887/130640/2016-00).In order to establish effective conservation strategy, drivers of local and regional patterns of biodiversity need to be understood. The composition of local biodiversity is dependent on a number of factors including evolution and redistribution of lineages through dispersal and environmental heterogeneity. Brazilian canga is characterised by a ferrugineous substrate, found both in the Iron Quadrangle of Minas Gerais and in the Carajás mountains in Amazonia. Canga is one of several specialised habitat types comprising Brazilian campo rupestre, a montane vegetation found within or adjacent to several major Brazilian bioregions, including the Atlantic Forest and Amazonia, with exceptionally high levels of diversity and endemism arising from both history of dispersal and environmental variation. In order to inform biodiversity conservation for canga, and more broadly for campo rupestre, we performed floristic and phylogenetic analyses investigating affinities between 28 sites on different substrates (canga and quartzite) and geographic locations (Carajás, Pará [Amazonia]; Cadeia do Espinhaço, Minas Gerais; Chapada Diamantina, Bahia). Through analysis of 11204 occurrences of 4705 species of angiosperms, we found that Amazonian Carajás canga plant communities formed a cohesive group, distinct from species assemblages found in Eastern Brazil (Minas Gerais, Bahia), either on canga or quartzite. The phylogenetic megatree of species across all sites investigated shows associations between certain clades and Amazonian canga, with few shared species between the Amazonian Carajás and Eastern Brazil sites, while the floristic comparison shows high levels of heterogeneity between sites. The need for reserves for Amazonian Carajás canga has been recognized and addressed by the creation of a national park. However, current sampling does not provide sufficient reassurance that the canga areas now benefitting from full legal protection adequately represent the regional canga flora.Publisher PDFPeer reviewe
Blind Testing: DNA Barcoding Sheds Light Upon the Identity of Plant Fragments as a Subsidy for Cave Conservation
Plants living above and around caves represent an important, albeit poorly studied, resource within cave ecosystems. The presence of plant material (root-like structures or rhizothemes, saplings, seeds, and seedlings) correlates positively with the biodiversity of the cave dwelling animals as shown for iron-ore caves in Carajás, Pará, Brazil. Plant material collected in caves has proven to be difficult to identify by traditional botanical methods, thus this research aims to provide a qualitative insight into the taxonomy and morphology of rhizothemes and other plant fragments found in the caves. The identification process used a combination of different molecular markers (ITS2, rbcL, and trnH-psbA) followed by a comparison of the sequences obtained against publicly available databases. The rhizothemes were submitted to micromorphological analysis to ascertain their putative root or stem origin and to compare their anatomy with known patterns found in the plant families or genera recovered through molecular matches. All studied samples were Angiosperms, mostly belonging to subclass Rosideae, within four orders: Malpighiales (Euphorbiaceae, Hypericaceae), Sapindales (Anacardiaceae and Sapindaceae), Myrtales (Myrtaceae), Fabales (Fabaceae), and only two belonging to subclass Asteridae, order Gentianales (Apocynaceae). Some of the samples were matched to generic level, with ITS2 being the best marker to identify the fragments because it shows high degree of sequence variation even at specific level and result reliability. All rhizothemes turned out to be roots, and correspondence was found between the existing literature and the individual anatomical patterns for the families and genera retrieved. DNA barcode has proved to be a useful tool to identify plant fragments found in this challenging environment. However, the existence of well curated, authoritatively named collections with ample biological information has proven to be essential to achieve a reliable identification
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