12 research outputs found
FIGURE 2. Mezilaurus conceicionensis. A in The novelty Mezilaurus conceicionensis (Lauraceae) and a key to the species of the genus from Brazilian Southeastern
No full textFIGURE 2. Mezilaurus conceicionensis. A, Holotype. Photo by Pablo Burkowski Meyer.Published as part of Alves, Flávio Macedo, Meyer, Pablo Burkowski & Assis, Leandro Cézanne De Souza, 2022, The novelty Mezilaurus conceicionensis (Lauraceae) and a key to the species of the genus from Brazilian Southeastern, pp. 185-192 in Phytotaxa 541 (2) on page 189, DOI: 10.11646/phytotaxa.541.2.8, http://zenodo.org/record/638878
Flowers to Òsanyìn: Lychnophora osanyiniana (Asteraceae: Vernonieae) a new "arnica da serra" from Minas Gerais, Brazil
No full textMarques, Danilo, Quaresma, Aline Silva, Meyer, Pablo Burkowski, Nakajima, Jimi (2021): Flowers to Òsanyìn: Lychnophora osanyiniana (Asteraceae: Vernonieae) a new "arnica da serra" from Minas Gerais, Brazil. Phytotaxa 491 (1): 57-64, DOI: 10.11646/phytotaxa.491.1.6, URL: http://dx.doi.org/10.11646/phytotaxa.491.1.
FIGURE 2. Lychnophora osanyiniana. A. Habitat and habit. B. Specimen occurrence habitat. C in Flowers to Òsanyìn: Lychnophora osanyiniana (Asteraceae: Vernonieae) a new "arnica da serra" from Minas Gerais, Brazil
No full textFIGURE 2. Lychnophora osanyiniana. A. Habitat and habit. B. Specimen occurrence habitat. C. Detail of leaves. D. Glomerule with mature florets. E. Glomerule surrounded by subinvolucral bracts. A–E. by P.B. Meyer.Published as part of Marques, Danilo, Quaresma, Aline Silva, Meyer, Pablo Burkowski & Nakajima, Jimi, 2021, Flowers to Òsanyìn: Lychnophora osanyiniana (Asteraceae: Vernonieae) a new "arnica da serra" from Minas Gerais, Brazil, pp. 57-64 in Phytotaxa 491 (1) on page 60, DOI: 10.11646/phytotaxa.491.1.6, http://zenodo.org/record/575719
Mezilaurus Alves & Meyer & Assis 2022
No full textKey to the Brazilian Southeast species of Mezilaurus 1. Leaves with erect indument abaxially; inflorescences in racemes with lateral branches raceme-like; bracteoles persistent; Brazilian Cerrado or Atlantic Forest; Minas Gerais and Espírito Santo states............................................................. Mezilaurus crassiramea - Leaves glabrous or glabrescent abaxially; inflorescences in racemes with lateral branches umbel-like; bracteoles deciduous; Atlantic Forest; Espírito Santo, Minas Gerais or Rio de Janeiro states..............................................................................................2 2. Globose flowers; globoid fruits; Vegetation on rocky outcrops (campo rupestre); Minas Gerais... Mezilaurus conceicionensis - Ellipsoid flowers; ellipsoid fruits; Atlantic Forest; Espírito Santo and Rio de Janeiro......................................................................3 3. Leaves narrow-elliptical or oblanceolate, 3–8.4 times longer than wide; Atlantic Forest; Rio de Janeiro......................................................................................................................................... Mezilaurus navalium (Allemão 1847: 265) Taub. ex Mez (1892: 112) - Leaves elliptic or obovate, 1.7–2.8 times longer than wide; Atlantic Forest; Espírito Santo............................................................4 4. Pedicelate flowers; filaments glabrous.............................................................. Mezilaurus glabriantha Alves & Souza (2012: 257) - Sessile flowers; filaments densely pubescent............. Mezilaurus sessiliflora P.L.R.Moraes & Vergne in Moraes et al. (2017: 153)Published as part of Alves, Flávio Macedo, Meyer, Pablo Burkowski & Assis, Leandro Cézanne De Souza, 2022, The novelty Mezilaurus conceicionensis (Lauraceae) and a key to the species of the genus from Brazilian Southeastern, pp. 185-192 in Phytotaxa 541 (2) on page 190, DOI: 10.11646/phytotaxa.541.2.8, http://zenodo.org/record/638878
Mezilaurus conceicionensis L. C. S. Assis, P. B. Meyer & F. M. Alves 2022, sp. nov.
No full text<p> <i>Mezilaurus conceicionensis</i> L.C.S.Assis, P.B.Meyer & F.M.Alves, <i>sp. nov.</i> (Figs 1–2).</p> <p> Type:— BRAZIL. Minas Gerais: Conceição do Mato Dentro, Fazenda Santa Cruz, Propriedade da Vale, 1025 m, 19°03’25”S, 43°24’11”W, 20 February 2019 (fl., fr.), <i>P.B. Meyer & N.L. de Paula 3803</i> (holotype, BHCB 203295!; isotype, RB!).</p> <p> <b>Diagnosis:—</b> <i>Mezilaurus conceicionensis</i> is similar in floral structure to <i>Mezilaurus revolutifolia</i>, however, it differs by having a shrubby habit, the branches distally puberulous, stamens connate and globoid fruits.</p> <p> Shrubs to small trees, 1.5–5 m tall. Branches with rhythmic growth; branchlets cylindrical, grayish to dark-brown, distally puberulous to glabrescent, with scars of senescent leaves and conspicuous lenticels. Apical buds totally covered by sericeous and translucent light-brown hairs. Leaves alternate to sub-opposite, clustered at the apex of the branchlets; petioles 0.6–1.8 cm long, 15–20% of the leaf length, plane to prominent at the adaxial surface, glabrous to subglabrous; blades 1.8–10 cm × 0.9–4.2 cm, obovate to oblanceolate, base attenuate, margins revolute, apex emarginate, rounded, obtuse or rarely mucronate, adaxial and abaxial surfaces glabrous to glabrescent, primary, secondary, and tertiary veins prominent at both surfaces, secondary veins brochidodromous, diverging at 35–75° to the primary vein, domatia absent. Cataphylls present, totally covered by sericeous and translucent light-brown hairs. Inflorescences 3.5– 6 cm long, dibotrya, lateral branchlets umbeliform, raquis cerose, partially covered by tomentose indument and lightcream hairs. Flowers 3–6 mm long, globose to sub-globose; pedicels 2.5–4.5 mm long, glabrous; hypanthium ca. 1 × 1.5 mm, cotiliform, inner and outer surfaces glabrous; tepals 0.2–0.6 × 0.5–1 mm, shorter than the hypanthium, ca. 1 / 3 of the flower length, subequal, outer tepals slightly shorter and wider than the inner ones, outer tepals depressed-ovate, glabrous to glabrescent, inner tepals broadly ovate to depressed-ovate, glabrous to glabrescent; stamens 1–1.1 mm long, connate, inserted at anthesis, filaments 0.5–0.6 mm long, rectangular, partially to totally covered by tomentose and opaque indument, anthers slightly deltate, glabrous, rarely papillose, locelli apical; pistil ca. 1.2 × 1.0 mm, ovary ca. 0.8 mm long, narrowly ellipsoid, glabrous. Style ca. 0.4 mm long, ca. 1 / 3 of the pistil length, glabrous. Fruits 1.8–3 cm, globose to subglobose, glaucous. Cupules ca. 1 × 4 mm, plane.</p> <p> <b>Paratypes:—</b> BRAZIL. Minas Gerais: Conceição do Mato Dentro, 1043 m, 19º02’47”S, 43º23’19”W, 16 February 2016 (fl.), <i>E. Tameirão-Neto & C.V. Vidal 5431</i> (BHCB!, RB!); 19º00’03”S, 43º24’05”W, 14 August 2016 (fl., fr.), <i>E. Tameirão-Neto & C.V. Vidal 5112</i> (BHCB!, RB!); 1005 m, 19º33’99”S, 43º23’13”W, 24 July 2014 (fl.), <i>C.V. Vidal 1258</i> (BHCB!, RB!); 1010 m, 19º34’98”S, 43º23’70”W, 11 December 2014 (fl.), <i>C.V. Vidal 1321</i> (BHCB!, RB!); Fazenda Santa Cruz, Propriedade da Vale, 1010 m, 19°03’04”S, 43°23’12”W, 20 February 2019 (fl., fr.), <i>P.B. Meyer & N.L. Paula 3775</i> (BHCB!); 1014 m, 19°03’03”S, 43°23’12”W, 20 February 2019 (fl., fr.), <i>P.B. Meyer & N.L. Paula 3776</i> (BHCB!); 1015 m, 19°03’03”S, 43°23’13”W, 20 February 2019 (fl., fr.), <i>P.B. Meyer & N.L. Paula 3777</i> (BHCB!); 1018 m, 19°03’03”S, 43°23’13”W, 20 February 2019 (fl., fr.), <i>P.B. Meyer & N.L. Paula 3778</i> (BHCB!); 1018 m, 19°03’03”S, 43°23’13”W, 20 February 2019 (fl., fr.), <i>P.B. Meyer & N.L. Paula 3779</i> (BHCB!); 1006 m, 19°03’04”S, 43°23’11”W, 20 February 2019 (fl., fr.), <i>P.B. Meyer & N.L. Paula 3780</i> (BHCB!); 1003 m, 19°03’04”S, 43°23’11”W, 20 February 2019 (fl., fr.), <i>P.B. Meyer & N.L. Paula 3781</i> (BHCB!); 1001 m, 19°03’05”S, 43°23’11”W, 20 February 2019 (fl., fr.), <i>P.B. Meyer & N.L. Paula 3782</i> (BHCB!); 993 m, 19°03’05”S, 43°23’10”W, 20 February 2019 (fl., fr.), <i>P.B. Meyer & N.L. Paula 3783</i> (BHCB!); 983 m, 19°03’05”S, 43°23’07”W, 20 February 2019 (fl., fr.), <i>P.B. Meyer & N.L. Paula 3784</i> (BHCB!); 1014 m, 19°03’03”S, 43°23’11”W, 20 February 2019 (fl., fr.), <i>P.B. Meyer & N.L. Paula 3785</i> (BHCB!); 1015 m, 19°03’03”S, 43°23’12”W, 20 February 2019 (fl., fr.), <i>P.B. Meyer & N.L. Paula 3786</i> (BHCB!); 1014 m, 19°03’03”S, 43°23’12”W, 20 February 2019 (fl., fr.), <i>P.B. Meyer & N.L. Paula 3787</i> (BHCB!); 1015 m, 19°03’03”S, 43°23’13”W, 20 February 2019 (fl., fr.), <i>P.B. Meyer & N.L. Paula 3788</i> (BHCB!); 1016 m, 19°03’03”S, 43°23’13”W, 20 February 2019 (fl., fr.), <i>P.B. Meyer & N.L. Paula 3789</i> (BHCB!); 1042 m, 19°03’20”S, 43°23’16”W, 20 February 2019 (fl., fr.), <i>P.B. Meyer & N.L. Paula 3790</i> (BHCB!); 1041 m, 19°03’03”S, 43°24’17”W, 20 February 2019 (fl., fr.), <i>P.B. Meyer & N.L. Paula 3791</i> (BHCB!); 1044 m, 19°03’21”S, 43°24’16”W, 20 February 2019 (fl., fr.), <i>P.B. Meyer & N.L. Paula 3792</i> (BHCB!); 1045 m, 19°03’21”S, 43°24’16”W, 20 February 2019 (fl., fr.), <i>P.B. Meyer & N.L. Paula 3793</i> (BHCB!); 1046 m, 19°03’21”S, 43°24’16”W, 20 February 2019 (fl., fr.), <i>P.B. Meyer & N.L. Paula 3794</i> (BHCB!); 1036 m, 19°03’22”S, 43°24’15”W, 20 February 2019 (fl., fr.), <i>P.B. Meyer & N.L. Paula 3795</i> (BHCB!); 1033 m, 19°03’23”S, 43°24’15”W, 20 February 2019 (fl., fr.), <i>P.B. Meyer & N.L. Paula 3796</i> (BHCB!); 1034 m, 19°03’23”S, 43°24’14”W, 20 February 2019 (fl., fr.), <i>P.B. Meyer & N.L. Paula 3797</i> (BHCB!); 1035 m, 19°03’24”S, 43°24’13”W, 20 February 2019 (fl., fr.), <i>P.B. Meyer & N.L. Paula 3798</i> (BHCB!); 1036 m, 19°03’24”S, 43°24’13”W, 20 February 2019 (fl., fr.), <i>P.B. Meyer & N.L. Paula 3799</i> (BHCB!); 1030 m, 19°03’24”S, 43°24’12”W, 20 February 2019 (fl., fr.), <i>P.B. Meyer & N.L. Paula 3800</i> (BHCB!); 1026 m, 19°03’25”S, 43°24’12”W, 20 February 2019 (fl., fr.), <i>P.B. Meyer & N.L. Paula 3801</i> (BHCB!); 1024 m, 19°03’25”S, 43°24’11”W, 20 February 2019 (fl., fr.), <i>P.B. Meyer & N.L. Paula 3802</i> (BHCB!); 1027 m, 19°03’25”S, 43°24’11”W, 20 February 2019 (fl., fr.), <i>P.B. Meyer & N.L. Paula 3804</i> (BHCB!). 19º30’11”S, 43º23’04”W, 16 August 2012 (fl., fr.), <i>E. Tameirão-Neto & C.V. Vidal 5156</i> (BHCB!, RB); Ibid., 1007 m, 19º05’13”S, 43º38’69”W, 30 July 2017 (fl.), <i>P.B. Meyer 3062</i> (BHCB!, CGMS!, K!, MO!, RB!); Ibid., Serra da Ferrugem, 19º00’03”S, 43º23’51”W, 27 July 2017 (fl., fr.), <i>A.S. Quaresma & C.T. Oliveira 854</i> (BHCB!, HEPH!, RB!).</p> <p> <b> <i>Distribution and ecology</i>:—</b> <i>Mezilaurus conceicionensis</i> is endemic to the <i>campos rupestres</i> over <i>canga couraçada</i> in the municipality of Conceição do Mato Dentro, State of Minas Gerais, Brazil (Fig. 5a of Assunção-Silva & Assis [2021] as <i>Mezilaurus sp. nov 1</i>), between 980–1050 m, associated to genus <i>Vellozia</i> Vandelli (1788: 32), a typical genus of <i>campos rupestres</i> (Fig 1).</p> <p> <b> <i>Phenology:</i> —</b> During fieldwork, the flowering of <i>M. conceicionensis</i> was continuously observed from August 2018 to July 2019, without interruptions, with peaks being recorded in the months of October 2018 and March 2019. Fruiting was also observed throughout this period, with peaks mostly from greater amounts of fruit being recorded between the months of May and July 2019.</p> <p> <b> <i>Etymology:</i> —</b> The epithet pays tribute to the type locality, the municipality of Conceição do Mato Dentro, MG, Brazil, located at the base of Serra da Ferrugem.</p> <p> <i> <i>Conservation status:—</i> Mezilaurus conceicionensis</i> is restricted to the Serra da Ferrugem mountain range (also called “Serra da Serpentina”), municipality of Conceição do Mato Dentro, State of Minas Gerais, Brazil. So far, it is known only from five subpopulations in this mountain range. According to the IUCN (IUCN 2012, 2016), this species can be tentatively be classified as Critically Endangered - CR (A4c;B1ab(iii) + 2ab(iii)). This classification is based on its small AOO, estimated in 0.49 km ², small EOO, calculate in 21.927 km ², and a continuing and probably not reversible reduction in its population size, based on the decline of this AOO, EOO and habitat quality.</p> <p> <i>Mezilaurus conceicionensis</i> is distinct from the remaining species of the genus by its shrubby habit, leaves with both surfaces glabrous to glabrescent, flowers clustered (umbel-like) along the lateral branches of the inflorescences, flowers globose, glabrous to glabrescent, tepals ca. 1 / 3 the flower length, shorter than the hypanthium, stamens connate and inserted, and globoid fruits.</p> <p> <i>Mezilaurus conceicionensis</i> can be confused with the collections of <i>M. revolutifolia</i> F.M.Alves & P.L.R.Moraes in Alves <i>et al.</i> (2011: 506), but the latter is characterized by its tepals as long as the hypanthium, ca. 1 / 2 the flower length to slightly larger, exserted and free stamens, and ellipsoid to obovoid fruits. <i>Mezilaurus conceicionensis</i> can also be confused with <i>M. crassiramea</i> (Meissner 1864: 117) Taubert ex Mez (1892: 112), also found in <i>campos rupestres</i> from the State of Minas Gerais. However, in <i>M. crassiramea</i>, the leaves are abaxially hirsute, villous or lanate, petioles are 1–10% of the leaf length, lanate to puberulous, the lateral branch of the inflorescences is racemiform, the stamens are exserted and free, and the fruits are ca. 3.1 × 2.8 cm, ellipsoid to obovoid. A key to the species of <i>Mezilaurus</i> from Southeastern Brazil is presented below.</p>Published as part of <i>Alves, Flávio Macedo, Meyer, Pablo Burkowski & Assis, Leandro Cézanne De Souza, 2022, The novelty Mezilaurus conceicionensis (Lauraceae) and a key to the species of the genus from Brazilian Southeastern, pp. 185-192 in Phytotaxa 541 (2)</i> on pages 186-190, DOI: 10.11646/phytotaxa.541.2.8, <a href="http://zenodo.org/record/6388781">http://zenodo.org/record/6388781</a>
Studies of the habitat and ecological relationships of the microendemic species Nicotiana gandarela Augsten & Stehmann (Solanaceae) reveal the importance of conserving geodiversity in the Iron Quadrangle.
No full textMicroendemic and/or endangered species, with little knowledge about their ecological requirements, need urgent investment in research to support conservation guidelines. The subject of this study is the microendemic species Nicotiana gandarela Augsten & Stehmann, Solanaceae family, which occurs exclusively in the locality of André do Mato Dentro, Serra da Gandarela, Santa Bárbara, MG, Brazil. The general objective was to characterize the phenology, ecophysiological aspects, elementome, environmental requirements of the species, in order to identify the main environmental factors/filters involved in its microendemic character, as well as its current distribution of occurrences. The phenological studies covered the reproductive and vegetative phenophases, every two weeks for 17 months. At the same time, the microclimatic variables of air humidity and temperature were recorded using a datalogger in order to identify possible phenological associations with the microclimatic variables. For the ecophysiological studies, the light intensity and light spectrum were characterized using a spectrometer, with three measurements during the day, 8am, 12pm and 3pm. Gas exchange analysis was carried out using a portable infrared gas analyzer (IRGA), with a 6 cm² aperture camera coupled with an LED light source. The electron transport rate (ETR) in relation to light intensity was obtained from rapid light curves using a fluorometer. The specific leaf area (SFA) was calculated based on leaf area (LA) and leaf dry mass (DM), using the formula SFA = LA/MD, with leaf area obtained through photography and digital image processing. The photosynthesizing pigments were extracted in DMSO (Dimethylsulphoxide) stored in amber glasses for 48 hours in dark conditions and at room temperature (22 ± 2 ºC) and quantified in a spectrophotometer reader for the following wavelengths: 480, 649 and 665nm. The content of total chlorophylls (Ca+b), the ratio between chlorophyll a and b (Ca/b), and the ratio between chlorophylls and carotenoids (total chlorophyll/carotenoids) were also calculated. For comparative soil analyses, samples were obtained from the microhabitats of the known populations, as well as from similar environments in the Serra da Gandarela, with the presence of dolomite outcrops, during the search for new population records. With regard to the phenological profile, the species had a higher proportion of annual individuals, with reproductive phenology concentrated in the dry season, with a certain phenological lag between subpopulations and individuals evaluated. A potential association of most of the phenophases was identified with the air humidity variable, and the other variables were eliminated due to the occurrence of multicollinearity. The rarity of the species is linked to its evolutionary and restrictive adaptation to intensely shaded environments formed by carbonate (domolitic) rock outcrops, in which the soil has high ph, magnesium and silt values. The results of the soil analysis and other characteristics of the microhabitats studied, together with the evidence obtained for the elementome of N. gandarela, indicate the potential existence of a highly specialized floristic community (dolomitophytes) and singular in the complex of dolomitic outcrops and dolomitic marbles of the Gandarela formation distributed in the Iron Quadrangle.Espécies microendêmicas e/ou ameaçadas de extinção, com escassos conhecimentos acerca de suas exigências ecológicas, necessitam investimentos urgentes em pesquisas para subsidiar diretrizes de conservação. O objeto de estudo se trata da espécie microendêmica Nicotiana gandarela Augsten & Stehmann, família Solanaceae, com ocorrência exclusiva para a localidade de André do Mato Dentro, Serra da Gandarela, Santa Bárbara, MG, Brasil. Como objetivo geral pretendeu-se caracterizar a fenologia, aspectos ecofisiológicos, elementoma e requerimentos ambientais da espécie, de forma a identificar os principais fatores/filtros ambientais envolvidos em seu caráter microendêmico, assim como sua atual distribuição de populações. Os estudos fenológicos contemplaram as fenofases reprodutivas e vegetativas, com frequência quinzenal, durante 17 meses. Concomitantemente foi feito o registro das variáveis microclimáticas de umidade do ar e temperatura, por meio de datalogger, para identificar possíveis associações fenológicas com as variáveis microclimáticas. Para os estudos ecofisiológicos, foi realizada a caracterização da intensidade luminosa e o espectro luminoso utilizando um espectrômetro, com três medições durante o dia, 8hs, 12hs e 15hs. As análises de trocas gasosas foram realizadas com um analisador portátil de gases infravermelho (IRGA), com câmara acoplada de abertura de 6 cm2 com uma fonte de luz LED. A taxa de transporte de elétrons (ETR) em relação à intensidade luminosa foi obtida a partir de curvas rápidas de luz utilizando um fluorômetro. A área foliar específica (AFE) foi calculada com base na área foliar (AF) e massa seca foliar (MS), pela fórmula AFE = AF/MS, sendo área foliar obtida por meio de fotografia e processamento digital das imagens. Os pigmentos fotossintetizantes foram extraídos em DMSO (Dimetilsulfóxido) acondicionado em vidros âmbar armazenados por 48 horas em condições escuras e sob temperatura ambiente (22 ± 2 º C) e quantificados em um leitor espectrofotômetro para os comprimentos de onda: 480, 649 e 665nm. O teor de clorofilas totais (Ca+b), razão entre clorofila a e b (Ca/b), e razão entre clorofilas e carotenoides (clorofila total/carotenoides) também foram calculadas. Para análises comparativas de solo foram obtidas amostras nos microhábitats das populações conhecidas, assim como em ambientes similares na Serra da Gandarela, com presença de lapas de afloramentos dolomíticos, durante a busca por novos registros de populações. Com relação ao perfil fenológico, a espécie apresentou maior proporção de indivíduos anuais, com fenologia reprodutiva concentrada na estação seca, com certa defasagem fenológica entre subpopulações e indivíduos avaliados. Foi identificada associação potencial de grande parte das fenofases com a variável de umidade do ar, sendo as demais variáveis eliminadas, devido a ocorrência de multicolinearidade. A raridade da espécie está atrelada à sua adaptação evolutiva e restritiva aos ambientes intensamente sombreados e formados pelos afloramentos rochosos carbonáticos (domolíticos), nos quais o solo apresenta altos valores de ph, magnésio e silte. Os resultados das análises de solo e demais características dos microhabitats estudados, juntamente com as evidências obtidas para o elementoma de N. gandarela, indicam a existência potencial de uma comunidade florística altamente especializada (dolomitófitas) e singular no complexo de afloramentos dolomíticos e de mármores dolomíticos da formação Gandarela distribuída no Quadrilátero Ferrífero.CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superio
Figure 3 from: Augsten M, Meyer PB, Freitas LB, Batista JAN, Stehmann JR (2022) Nicotiana gandarela (Solanaceae), a new species of 'tobacco' highly endangered from the Quadrilátero Ferrífero in Brazil. PhytoKeys 190: 113-129. https://doi.org/10.3897/phytokeys.190.76111
No full textFigure 3 A main mountains of the Quadrilátero Ferrífero in Minas Gerais. Star indicates the Nicotiana gandarela Augsten & Stehmann occurrence site B Google Earth image showing the regional landscape associated with the N. gandarela site, the forest matrix impacted by a small village, and open mining. The red lines indicate mining concessions (Instituto Prístino: Atlas Digital Geoambiental [https://institutopristino.org.br/atlas/])
DINÂMICA ESTRUTURAL EM UM FRAGMENTO DE FLORESTA ESTACIONAL SEMIDECIDUIFÓLIA EM LAVRAS, MG, BRASIL
No full textNeste trabalho, objetivou-se descrever a dinâmica estrutural da comunidade arbórea de um fragmento de floresta semideciduifólia (Mata do Capivari), situado em Lavras, Minas Gerais. O estudo teve como base três inventários realizados no período de onze anos (1997, 2003 e 2008) em 28 parcelas permanentes de 20×20 m onde foi registrada a espécie e a medida de diâmetro à altura do peito (DAP) das árvores com DAP ≥ 5 cm, incluindo sobreviventes, mortas ou recrutas. A hipótese foi de que os padrões de dinâmica do primeiro período (1997 a 2003) persistiram no segundo (2003 a 2008). Os descritores da dinâmica foram taxas de mortalidade e recrutamento de árvores individuais (dinâmica demográfica), taxas de ganho e perda de área basal (dinâmica da biomassa) e as respectivas taxas de mudança líquida. Entre 2003 e 2008, a taxa de mortalidade, de 3,30%.ano-1, superou a de recrutamento, de 2,78%.ano-1. A taxa de ganho em área basal foi de 2,72%.ano-1, pouco inferior à de perda, de 2,98%.ano-1. De maneira geral, os padrões repetiram os do primeiro período (1998 a 2003), com persistência de um lento declínio demográfico, particularmente concentrado nas proximidades do rio, e uma área basal próxima da estabilidade, ao contrário da alta encosta, onde ocorreu uma significativa expansão. Comparativamente, a Mata do Capivari é uma das mais estáveis entre as estudadas na região, a despeito da persistente interferência human
Nicotianagandarela (Solanaceae), a new species of ‘tobacco’ highly endangered from the Quadrilátero Ferrífero in Brazil
No full textNicotianagandarela Augsten & Stehmann (Solanaceae), sp. nov., a small ’tobacco’ known only from one locality at Serra do Gandarela, in the state of Minas Gerais, Brazil, is described and illustrated. It is morphologically characterized by its rosulate basal leaves, red corolla with a short tube not inflated at the apex, and the peculiar habitat, a shaded site under a rocky outcrop ledge along a forested stream. Phylogenetic analyses based on a combined dataset of nuclear (ITS) and plastid (ndhF, trnLF, and trnSG) DNA sequences revealed that the species belongs to the Nicotianasect.Alatae and is sister to the clade with the remaining species in the section. A key for the identification of Brazilian species of the section is given. The unusual habitat, the small population size, and the intense pressure of mining activities in the surroundings made the species assessed as Critically Endangered (CR), needing conservation efforts to avoid its extinction
Structural dynamics in a fragment of seasonal semideciduous forest in Lavras, MG, Brazil
No full textThe present contribution aimed at describing the structural dynamics of the tree community of a forest fragment of seasonal semi-deciduous forest (Mata do Capivari) situated in Lavras, Minas Gerais State, South-eastern Brazil. The study was based on three surveys carried out during an 11-year period (1997, 2003 and 2008) in 28 20×20 m permanent plots where records were made of the species and diameter at breast height (dbh) of trees with dbh ≥ 5 cm, including survival, mortality and recruits. The hypothesis was that the patterns of dynamics found in the first interval (1997-2003) persisted in the second (2003-2008). The descriptors of dynamics were the rates of mortality and recruitment of individual trees (dynamics of demography), rates of gain and loss of tree basal area (dynamics of biomass), and respective net change rates. Between 2003 and 2008, the mortality rate, of 3.30%.yr-1, surpassed the recruitment rate, of 2.78%.yr-1. The gain rate in basal area was 2.72%.yr-1, only a little inferior to the loss rate, of 2.98%.yr-1. In general, these patterns repeated those of the first interval (1998-2003), with a persisting slow demographic decline, particularly concentrated near the river, and a nearly stable basal area. Comparatively speaking, the Mata do Capivari is one of the most stable among those studied in the region despite persistent human interference.Neste trabalho, objetivou-se descrever a dinâmica estrutural da comunidade
arbórea de um fragmento de floresta semideciduifólia (Mata do Capivari), situado em
Lavras, Minas Gerais. O estudo teve como base três inventários realizados no período
de onze anos (1997, 2003 e 2008) em 28 parcelas permanentes de 20×20 m onde foi
registrada a espécie e a medida de diâmetro à altura do peito (DAP) das árvores com DAP
≥ 5 cm, incluindo sobreviventes, mortas ou recrutas. A hipótese foi de que os padrões de
dinâmica do primeiro período (1997 a 2003) persistiram no segundo (2003 a 2008). Os
descritores da dinâmica foram taxas de mortalidade e recrutamento de árvores individuais
(dinâmica demográfica), taxas de ganho e perda de área basal (dinâmica da biomassa)
e as respectivas taxas de mudança líquida. Entre 2003 e 2008, a taxa de mortalidade,
de 3,30%.ano-1, superou a de recrutamento, de 2,78%.ano-1. A taxa de ganho em área
basal foi de 2,72%.ano-1, pouco inferior à de perda, de 2,98%.ano-1. De maneira geral,
os padrões repetiram os do primeiro período (1998 a 2003), com persistência de um
lento declínio demográfico, particularmente concentrado nas proximidades do rio, e
uma área basal próxima da estabilidade, ao contrário da alta encosta, onde ocorreu uma
significativa expansão. Comparativamente, a Mata do Capivari é uma das mais estáveis
entre as estudadas na região, a despeito da persistente interferência humana
