Effects of experimental lightgaps and topography on enrichment plantings in a central Amazonian secondary forest

Enrichment plantings into secondary forest are an important option in restoring species diversity and ecosystem services. However, little attention has been given to environmental requirements for species performance. This study evaluated the effects of lightgaps and topographic position on the growth and survival of four native tree species (Pouteria caimito, Garcinia macrophylla, Dipteryx odorata and Cynometra bauhiniaefolia) planted into a 26-year old secondary forest originating from abandoned pastures in the central Amazon Basin. Artificial lightgaps and control plots under closed canopy were uniformly distributed on plateaus and bottomlands near water bodies. Seedlings were planted randomly into the plots and monitored for 28 months. Seedling survival rate was high (93%) and did not differ among species. Overall, lightgaps produced a 38% increase in seedling height relative to the controls. Although the four species naturally occur in mature forest, two of the four grew significantly more in lightgaps than in closed canopy secondary forest. Overall, bottomlands facilitated greater seedling growth in height (38%) relative to plateaus, but only one species exhibited a significant increase. This study shows the importance of the environmental variability generated with canopy openings along the topographic gradient, suggesting that both the selection of species and microsite conditions of planting sites have to be considered important criteria in the recovery of degraded areas. (AU)

Scientific assessment of physical growth and development in children / 中国实用儿科杂志

The weight development can be used to indicate children's nutritional status. But the assessment of stature development in children is more complicated,which involves genetics,endocrine,nutrition and bone metabolism. Parents should regularly follow up on the growth and development of children. At the same time,the growth data of children should be kept by parents. Pediatricians can obtain important information from the child's development history to help assessment and diagnosis. Before dealing with this thorny problems of social and medical confusion,primary care pediatricians(PCP)should learn the knowledge of height growth during childhood,including the normal range and rules of height growth. Meanwhile,PCP need to understand the factors affecting the height growth in order to make proper management.

Improved tree height estimation of secondary forests in the Brazilian Amazon / Estimativa melhorada de altura de árvores em florestas secundárias da Amazônia brasileira

This paper presents a novel approach for estimating the height of individual trees in secondary forests at two study sites: Manaus (central Amazon) and Santarém (eastern Amazon) in the Brazilian Amazon region. The approach consists of adjusting tree height-diameter at breast height (H:DBH) models in each study site by ecological species groups: pioneers, early secondary, and late secondary. Overall, the DBH and corresponding height (H) of 1,178 individual trees were measured during two field campaigns: August 2014 in Manaus and September 2015 in Santarém. We tested the five most commonly used log-linear and nonlinear H:DBH models, as determined by the available literature. The hyperbolic model: H = a.DBH/(b+DBH) was found to present the best fit when evaluated using validation data. Significant differences in the fitted parameters were found between pioneer and secondary species from Manaus and Santarém by F-test, meaning that site-specific and also ecological-group H:DBH models should be used to more accurately predict H as a function of DBH. This novel approach provides specific equations to estimate height of secondary forest trees for particular sites and ecological species groups. The presented set of equations will allow better biomass and carbon stock estimates in secondary forests of the Brazilian Amazon.

Este trabalho apresenta uma nova abordagem para a estimativa de altura de árvores em florestas secundárias em duas áreas de estudo na Amazônia brasileira: Manaus (Amazônia central) e Santarém (Amazônia oriental). A abordagem consistiu em ajustar modelos hipsométricos separados por área de estudo e grupos ecológicos de espécies: pioneiras, secundárias iniciais e secundárias tardias. No total, 1178 árvores foram medidas em diâmetro e altura em duas etapas de campo: agosto de 2014 em Manaus e Setembro de 2015 em Santarém. Foram testados cinco modelos log-lineares e não lineares mais utilizados na literatura. O modelo hiperbólico: H = a.D/(b+D) foi o que apresentou o melhor ajuste quando avaliado com os dados de validação. Diferenças significativas nos parâmetros de ajuste foram observadas entre as espécies pioneiras e secundárias de Manaus e Santarém pelo teste F, significando que equações específicas por grupos ecológicos e área de estudo deveriam ser utilizadas para estimar a altura (H) a partir do diâmetro (D) com maior acurácia. Esta nova abordagem fornece equações específicas para localidade e grupo ecológico, para estimar a altura das árvores em florestas secundárias. O conjunto de equações desenvolvidas permitirá melhorar as estimativas de biomassa e a quantificação dos estoques de carbono nas florestas secundárias da Amazônia brasileira.

Effect of environmental factors on the productivity of crimean pine (Pinus nigra ssp. pallasiana) in Sutculer, Turkey.

This study was conducted on Pinus nigra sub sp. pallasiana commonly known as crimean pine. The purpose of this study was to determine the important site factors affecting the development of these forests in Sutculer district. This district experiences a transitional climate between Mediterranean and Continental regions. There is a strong water deficit in summer. The data was collected from 37 sample plots. It was analyzed statistically by using upper stand height as a dependent variable and some site characteristics as independent variables. The results revealed that there was only one important negative linear relationship between upper stand height and Ah organic matter. This result was uncommon. The reasons for this depend indirectly other site factors (aspect, slope position, altitude, slope degree and humus forms). This result was explained at 69.53% of total variance using these site factors by means of factor analysis (FA). After FA, these site factors were transferred to stepwise disciriminant analysis (SDA) to determine eigenvalue ratios of the bonitet models. As a result of SDA, three bonitets and five variables (3B5V) were found as the best model with 71.5 % of variance and 0.007 % significance level.

Effects of release cutting on the development of young natural lebanon cedar (Cedrus libani A. Rich) stands of western Mediterranean region of Turkey.

Release cutting is ecologically and economically one of the most important silvicultural treatments for establishing a new stand. The study was designed to determine the suitable silvicultural treatments of different spacing of thinning for release cutting on young natural lebanon cedar (Cedrus libani A. Rich) stands at the thicket stage. Studies were carried out at Bucak and Gölhisar forest districts in the Western Mediterranean region of Turkey between the years of 1999-2005. Results showed that release cutting treatment had a positive effect on diameter growth for individual trees with the 1.5 m x 3 m spacing and positively correlated with spacing of thinning. However, there was not significant effect of the thinning application on height growth of young natural Lebanon cedar stands.