João Juares Soares

Estudo etnobotânico na comunidade de Conceição-Açu (alto da bacia do rio Aricá Açu, MT, Brasil)

This paper aims at doing the ethnobotany survey of plants classified in different categories of use in the community of Conceicao-Acu, in the city of Cuiaba, MT, Brazil and estimate the value of use of the species botanic in the gallery forest. Structured and non-structured interviews and the questionnaire were used in 59 adult dwellers of both sexes. Were identified the landscape units: backyards, husbandry and gallery forest and the total number of used species is the 180. The majority of the plants was collected during the interview and is kept in the Herbary of the Federal University of Mato Grosso. In the backyards of the house, 86 species, belong 43 families were identified, the majority of which planted and utilized as food (48.1%) an used as medicinal (44.5%). In the husbandry the cultivation principal are: Manihot esculenta L. (100%), Carica papaya L. (76.2%), Musa paradisiaca L. (71.4%), Saccharum officinarum L. (57.1%). In the gallery forest the use value showed the medicinal categoty (65%) species: Copaifera langsdorffii Desf. (2.5), Aspidosperma polyneuron Muell. Arg. (2.5), Hymenaea stignocarpa Mart. (2.33), Diptychandra aurantiaca Tul. (2.0), Cariniana rubra Gardner ex. Miers (2.0) and the Mimosaceae, Bignoniaceae, Caesalpiniaceae, Fabaceae and Sapindaceae families were the most used. The results show that the populacion has a wide knowledge of the plants and of the his power of healing.

Current State and projection of the probable original vegetation of the São Carlos region of São Paulo State, Brazil

A map of the native vegetation remaining in São Carlos County was built based on aerial images, satellite images, and field observations, and a projection of the probable original vegetation was made by checking it against soil and relief surveys. The existing vegetation is very fragmented and improverished, consisting predominantly of cerrados (savanna vegetation of various physiognomies), semideciduous and riparian forest, and regeneration areas. Araucaria angustifolia (Bertol.) Kuntze, found in patches inside the semideciduous forest beginning at a minimum altitude of 850 m, has practically disappeared. By evaluating areas on the map for different forms of vegetation, we obtained the following results for original coverage: 27% cerrado (sparsely arboreal and short-shrub savanna, and wet meadows); 16% cerradão (arboreal savanna); 55% semideciduous and riparian forests; and 2% forest with A. angustifolia. There are now 2% cerrados; 2.5% cerradão; 1% semideciduous forest and riparian forests; 1.5% regeneration areas; and 0% forest with A. angustifolia.

Networks of epiphytic orchids and host trees in Brazilian gallery forests

Species interactions have been recently depicted as networks, in which each species is connected to one or more other species in binary interaction matrices. Forty networks of epiphytic orchid and host tree species were assessed in Brazilian gallery forests. The nestedness of the networks was estimated with the NODF index and the significance was tested with null models. The phylogenetic structure of the network was also assessed, by searching for phylogenetic signals in the number of interactions and in the similarity of interacting species. In total, 105 orchid speciesand132hosttreespeciesweresampled.Anestedpatterninallorchid-hosttreenetworkswasfound.However, phylogenetic signals were not observed. The results support that the host specificity of orchids is small and most of the interactionsoccuramonggeneralistorchidsandgeneralisthosttrees.Whiletheconceptofspecies-specificitycanthus be rejected, the extreme alternative - that interacting orchids and host trees are not a random subset of the regional species pool - can be dismissed as well. However, factors other than phylogenetic history may structure interaction networks of epiphytic orchids and host trees.

Twenty years of post-fire plant succession in a "cerrado", São Carlos, SP, Brazil

Secondary succession in degraded areas is little studied, especially where long-term observation of evolutionary processes is concerned. The aim of this work was to follow the qualitative and quantitative changes in vegetation throughout the regeneration process after fire in a cerrado with forest physionomy. The area under study is a reserve on CPPSE-EMBRAPAs farm, São Carlos region of São Paulo State, Brazil. In 1981, an especially destructive fire eliminated the aerial part of the vegetation and litter. From that time, the vegetation in three permanent quadrats of 2 x 20 m was recorded for twenty years. The results demonstrated the rapid growth of herbs, shrubs, climbers and trees successively, with a great species richness and, after a certain time, a decline in density at a rate similar to the initial recovery. Both the soil seed bank and sprouting subterranean organs played important parts in the recovery of the vegetation. Three phases were observed in the plant succession: plant growth, followed by intraspecific competition with a reduction in the number of individuals and finally interspecific competition with the disappearance of some species from the quadrats. The different populations behaved similarly and the rise and fall in density of each species over time reflected their ecological role.

Contribuição das folhas de lianas na produção de serapilheira em um fragmento de floresta estacional semidecidual em São Carlos, SP

A producao de serapilheira em um fragmento de floresta estacional semidecidual foi analisada durante 12 meses, sendo o material recolhido separado em fracoes de: galhos, material reprodutivo, folhas de especies de lianas e folhas de demais especies. O total de material produzido foi de 12.221 kg ha-1 ano-1, sem diferenca significativa entre os meses observados e sem relacao significativa tambem com o periodo seco. A fracao das folhas teve a maior contribuicao com 7.750 kg ha-1 ano-1, da qual 2.317 kg ha-1 ano-1 (19%), correspondem as folhas de lianas, que apresentam ampla distribuicao no fragmento. A maioria das lianas contudo, nao apresentaram deciduidade marcante como ocorre com algumas especies arboreas desse tipo florestal. A producao de folhas de lianas para a serapilheira e constante, porem uma maior queda foi relacionada com a alta evapotranspiracao real ocorrida no periodo de estudo.

SEASONAL SEMIDECIDUAL FOREST FRAGMENT SOIL SEED BANK AND IT’S RELATIONSHIP WITH CONSERVATION

http://dx.doi.org/10.1590/1806-90882017000300011 ABSTRACT – Soil seed banks are the first source of seeds for regeneration after a forest’s disturbance. The present study aims to verify the regeneration potential of the soil seed bank of a Seasonal Semidecidual Forest remnant. The study was carried out at Canchim Farm, CPPSE Embrapa (São Paulo State, Brazil). Soil samples were collected from the fragment in both the wet and dry seasons. An average of 307.8 seedlings/m was found in the dry season and an average of 144 seedlings/m was found in the dry station. Twenty six species of trees with viable seeds were found in the soil, mostly pioneer species; among them, Cecropia glaziovi Snethlage was the most abundant pioneer species. The soil seed bank can be considered of great potential for regeneration due to the presence of pioneers, secondary and later species.