anatomia do lenho e dendrocronologia de lianas da família ...

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MATERIALS AND METHODS
There were sampled fifty-seven lianas from eight species belonging to Leguminosae family,
subfamilies Mimosoideae and Papilionoideae (Table 1). The samples were collected at the
Parque Nacional do Itatiaia, municipality of Itatiaia, State of Rio de Janeiro, south-eastern
Brazil. Placed between geographical coordinates 22°15’ and 22°30’ S, 44°30’ and 44°45’ W,
within an area of 28,155.97 hectares (http://www.ibama.gov.br). The vegetation type is
Atlantic rain forest (Oliveira-Filho & Fontes, 2000). The Itatiaia range has a predominant
mountainous relief with several well-delimited climatic and vegetation belts related with
altitudinal gradient. The belt where the samples were taken is between 700 m and 1,100 m,
with annual mean precipitation of 1,699 mm, and annual mean temperature 18.2 °C. This
ambient is warm and rainy from December to February and cold and dry from June to August.
From December to February falls 50 % of the annual precipitation and January is the rainiest
month with an average of 289.2 mm. In these months the mean of temperature is 20.8°C.
From June to August falls only 5 % of the annual precipitation and the least rainy month is
June with average 31.5 mm. This cold and dry season has the mean temperature of 15.1 °C,
but was registered absolute minimum of 0 °C. The climate is temperate and humid, and by
Köppen’s system is the Cfb type (Segadas-Vianna & Dau 1965).
There were selected for this study lianas with diameter larger than 2.0 cm at approximately
1.3 m above the ground without wounds or deformities in this height. The number of samples
per species differed by the difficult to meet individuals with characteristics cited above and
different abundance of each species. From each sampled individual, a voucher was also
collected, with reproductive and others vegetative parts, which were deposited in herbarium
collection of the Jardim Botânico do Rio de Janeiro (RB).
Wood samples of stems were collected at approximately 1.3 m above the ground. There were
taken partial or complete cross-sections with approximately 2 cm length, including bark,
wood and some times the medulla. Blocks were polished for macroscopic observation with
hand lens and stereomicroscope Olympus SZ11. The images were taken with photographic
camera Olympus C5050 attached to the same stereomicroscope.
For light microscopy, boiling water and glycerine were used to soft part of the blocks.
Sections with 16 to 30 µm thick were made in transversal, tangential and radial plains with
Spencer 860 sliding microtome. After that they were cleaned, stained with safranin and astra
blue (Bukatsch, 1972), dehydrated and mounted on Permount resin in permanent slides.
Slides were observed at Olympus microscope BX50 and images captured with system Image