1000 resultados para Cerrado e Mata ciliar


Relevância:

30.00% 30.00%

Publicador:

Resumo:

Pós-graduação em Agronomia (Ciência do Solo) - FCAV

Relevância:

30.00% 30.00%

Publicador:

Resumo:

A Mata Atlântica, um dos biomas mais ameaçados do mundo, possui alta biodiversidade e endemismos, restando apenas 7% de sua área original, e por isso considerada um hotspot. O município de Campinas está incluído no domínio vegetal de Mata Atlântica com transição para Cerrado, onde restam menos de 3% de floresta estacional semidecidual. A fragmentação de áreas naturais, a caça ilegal e a introdução de espécies exóticas são as principais causas de extinção de espécies. Neste estudo buscou-se identificar a riqueza e a densidade populacional de primatas em dez fragmentos de mata na região da Área de Proteção Ambiental de Sousas e Joaquim Egídio, área de ocorrência do sagüi-do-tufo-preto (Callithrix penicilatta), do macaco-prego (Cebus nigritus) e dos ameaçados, segundo a IUCN (2007), sagüi-da-serra-escuro (Callithrix aurita), sauá (Callicebus nigrifrons) e bugio-ruivo (Alouatta guariba clamitans). Os fragmentos variam entre dois e 24ha com formatos variados e de diferentes composições de capoeiras e matas secundárias, numa matriz agrícola, composta de pastagens, silvicultura e culturas perenes e anuais. O levantamento foi feito entre maio de 2007 e outubro de 2008 através de contagens absolutas dos grupos, diferenciados pelo local dos reavistamentos, composição sexual e etária. Cada avistamento foi georreferenciado com um GPS Garmin Camo Etrex®. Por serem territoriais, sauás foram atraídos através do uso de playbacks. A comunidade de primatas da Mata Ribeirão Cachoeira (245ha), maior remanescente local, é composta por cinco espécies. Sagüi-detufo- preto e bugio foram avistados em seis fragmentos e sauás em dois. Em cinco, foram observados grupos de Callithrix jacchus (sagüi-comum), exóticos na região. Em três fragmentos foram encontrados grupos mistos ou híbridos de Callithrix jacchus e C. penicillata. A área total...(Resumo completo, clicar acesso eletrônico abaixo)

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

30.00% 30.00%

Publicador:

Resumo:

The aim of this study was to determine the effect of nitrogen (N) and the phosphorus (P) in seedlings of Amburana cearensis planted in areas occupied by Brachiaria decumbens, in an Oxisol, which originally had a Dense Savanna and in a Plinthic surrounding a Gallery Forest. We evaluated the response of A. cearensisgrowth and survival in the absence and doses of -1 10, 20 and 40 kg ha N, as urea and absence and doses of 10, 20 and -1 40 kg ha P, in the form of triple superphosphate in a randomized complete block design. We evaluated the stem diameter at four, eight and twelve months after planting. At the end of the first year were evaluated crown diameter and survival. According to the classification proposed in this study the growth of A. cearensis can be considered very slow in the Oxisol, regardless of fertilization, very slow when fertilized with N in the Plinthic and slow when fertilized with P. Despite the lower growth in Oxisol, the A. cearensis showed higher nutritional requirement there. The A. cearensis seedlings showed moderate nutritional requirement for N and high for P. In Plinthic, their nutritional requirement for P was moderate and total N present in the soil was sufficient to meet growth demand in this stage. This small nutritional requirement for N may be associated with its ability to nodulation.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Dissertação (mestrado)—Universidade de Brasília, Instituto de Ciências Biológicas, Programa de Pós-Graduação em Zoologia, 2015.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The poison frog genus Ameerega (Dendrobatidae) currently contains 32 species. They are distributed from central Brazil into western Amazonia to the lower Andean versant. In addition, three trans-Andean species have been allocated to Ameerega (Andrade et al. 2013; Frost 2014). Ameerega berohoka (Vaz-Silva & Maciel 2011) was described based on specimens from central Brazil (type-locality: Arenópolis, GO) and it is assumed to occur in parts of western and southwestern state of Goiás (Frost 2014). More recently, Andrade et al. (2013) extended its distribution to the state of Mato Grosso. Here we re-describe the advertisement call of A. berohoka, providing additional information regarding its temporal structure and spectral traits. Our observations also consist of a new distribution record for this species to the state of Mato Grosso.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The objective of this study was to evaluate the horizontal and vertical structures of tree community in regeneration in a fragment of a secondary riparian forest at approximately 30 years of age and to identify the most abundant species in each fragment of the forest to determine the sucessional stage. An area of 800 m² was subdivided into 16 samples of 10 x 5 m and all individuals with DBH ≥ 1 cm were sampled and identified for the following analyzes: horizontal parameters (DR, FR, DoR, IVC and IVI), vertical parameters (PSR and RNR) and mixed parameters, from of value of increased importance index (IVIa). The survey measured 689 individuals, belonging to 38 families, 74 genus and 109 species. The total density was 8,614 individuals/ha. The index of Shannon´s diversity was 3.99 and the index of Pielou´s equability was 0.85. Tibouchina pulchra, Psychotria suterella and Endlicheria paniculata obtained high values of IVIa. Guarea macrophylla, Gomidesia anacardiaefolia, Xylopia langsdorffiana and Endlicheria paniculata achieved high values of RNT, indicating adequate natural regeneration in the plot. The initial secondary and umbrophylous species showed the highest ecological importance in this fragment of the forest, with the highest values of sociologic position and importance index. Furthermore, the presence of late secondary species in all layers suggest that the studied fragment is in intermediate succession degree.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The Jaguariaiva region is located at Parana State, southern Brazil, and it keeps up the last remnants of savanna vegetation in the State. Thus, it should be considered a mark of the meridional distribution limit of this vegetation type in Brazil. The Parque Estadual do Cerrado (24º09' S; 50º18' WG), whose vegetation is not solely composed by savanna forms, was the object of this study that analysed the vegetation of two dominant savanna physiognomic types (cerrado sensu stricto and campo cerrado). Twenty quadrats of 200m² (20 x 10m) were sistematicaly established in each physiognomic unit, and all the individuals having Basal Perimeter (BP) over 15 cm were sampled. The survey results indicated a low number of woody species in both units (33 species in cerrado sensu stricto and 18 in campo cerrrado). Most important species were virtually the same for both units, specially Byrsonima coccolobifolia, Acosinium subelegans, Couepia grandiflora and Stryphnodendron adstringens. The total density, total dominance and diversity were higher in cerrado sensu stricto. Moreover. there was apparently a higher lloristic resemblance with savannas of São Paulo State, specially those located in the South of thc State.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This study subject to investigate the floristic composition and richness, the reproductive phenological patterns, the dispersal syndromes and life forms of species of a disjunt cerrado in semiarid climate at Araripe plateau during a one year period. We found 107 species and 41 families. Fabaceae, Myrtaceae, Poaceae, Apocynaceae, Euphorbiaceae and Malpighiaceae showed the largest number of species. For 47 of the woody species found, we studied the geographical distribution based on 27 papers of the Brazilian cerrados. Twelve species are of widespread occurence in the cerrado, and 13 are restricted to the Araripe plateau. Zoocory, autocory, and anemocory are the predominant syndromes of dispersal. The predominant life forms were phanerophytes (50.7%), hemicriptophytes (14.9%) and camephytes (13.1%). The cerrado of Araripe have lower species richness than continous cerrados, but a similar pattern of reproductive phenology, dispersal syndromes and life forms in more humid zones.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Size distributions in woody plant populations have been used to assess their regeneration status, assuming that size structures with reverse-J shapes represent stable populations. We present an empirical approach of this issue using five woody species from the Cerrado. Considering count data for all plants of these five species over a 12-year period, we analyzed size distribution by: a) plotting frequency distributions and their adjustment to the negative exponential curve and b) calculating the Gini coefficient. To look for a relationship between size structure and future trends, we considered the size structures from the first census year. We analyzed changes in number over time and performed a simple population viability analysis, which gives the mean population growth rate, its variance and the probability of extinction in a given time period. Frequency distributions and the Gini coefficient were not able to predict future trends in population numbers. We recommend that managers should not use measures of size structure as a basis for management decisions without applying more appropriate demographic studies.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Due to its geographical location, the northeastern Coast of Brazil (Litoral Setentrional do Nordeste - LSN) is a hotter and drier climate than the eastern coast. In addition, because of its proximity to caatinga and cerrado, the LSN contains species from these vegetation biomes and from the restinga on the coast, which comprise different plant formations and creates a vegetation complex. Despite the great importance of this ecotone, there are few studies about its flora. The objective of this work was to contribute to what is known about the floristic and phytosociological composition of this region. We made a floristic survey in the area (between 2007 and 2011), consulted herbaria data from the region and made a phytosociological study in a stretch of coastal semideciduous forest (mata de tabuleiro). The study recorded 382 plant species from 96 families. In the phytosociological survey (0.32 ha) we recorded 2,970 individuals and 52 species. The most abundant plants surveyed were the trees Manilkara triflora, Chamaecrista ensiformis and Guapira nitida and the shrubs Cordiera sessilis and Maytenus erythroxyla (average height 3.8 m, average diameter 6.2 cm, basal area 39.28 m²/ha). The local flora includes floristic elements of caatinga, cerrado and restinga, corroborating the idea that the plant community of the coastal region of Ceará has an ecotonal nature.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Carbon and nitrogen biogeochemical cycles in savannas are strongly regulated by the seasonal distribution of precipitation and pulses of nutrients released during the wetting of the dry soil and are critical to the dynamics of microorganisms and vegetation. The objective of this study was to investigate the spatial and temporal variability of C and N isotope ratios as indicators of the cycling of these elements in a cerrado sensu stricto area, within a protected area in a State Park in the state of São Paulo, Brazil. The foliar δ13C and δ15N values varied from -33.6 to -24.4 ‰ and -2.5 to 4.5 ‰, respectively. The δ13C values showed a consistent relationship with canopy height, revealing the importance of structure of the canopy over the C isotopic signature of the vegetation. Carbon isotopic variations associated with the length of the dry season indicated the importance of recent fixed C to the integrated isotopic signature of the leaf organic C. The studied Cerrado species showed a depleted foliar δ15N, but a wide range of foliar Nitrogen with no difference among canopy heights. However, seasonal variability was observed, with foliar δ15N values being higher in the transition period between dry and rainy seasons. The variation of the foliar C and N isotope ratios presented here was consistent with highly diverse vegetation with high energy available but low availability of water and N.