3 resultados para Trees in cities

em Bioline International


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Management of coconut ( Cocos nucifera ) lethal yellowing disease (CLYD), which has killed about eight million coconut trees in Mozambique, has proved challenging. The objective of this study was to investigate the impact of farming practices and related history, on the CLYD incidence in Mozambique. The methodology included a socioeconomic questionnaire to the households and direct observations on the palm farms. The collected data were analysed using logistic regression. Five out of 11 explanatory variables tested, namely farm age, availability of other palm species on the coconut farm, type of coconut varieties grown, root cut practices, and intercropping had a significant (P< 0.05) effect on CLYD incidence. Coconut farms <10 years had higher odds of higher disease incidence compared to the farms between 10 to 40 years old. The presence of other palm species in the coconut farms had two times higher odds of having higher disease incidence levels compared to farms without other palm species. Tall coconut varieties were likely to be more tolerant to CLYD compared to dwarf varieties. Coconut farms with some kind of intercropping had two times higher odds of having higher disease incidence levels compared to pure stands. The practice of cutting coconut roots had three times higher odds of having high disease incidence levels compared to non-practicing farms. Farm age, availability of other palm species on the coconut farm, type of coconut varieties grown, root cut practices and intercropping need to be considered for integrated CLYD management.

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The morphometric relations allow describing dimensions of trees without prior knowledge of the age, it help the forest planning and implementation of silvicultural treatments, especially when needs to make sustainable use of forests. For this purpose, the aim of this study was to model and comparising the morphometric relations araucaria trees in social position dominant, codominant and dominated in native forest remnant, located in Lages, SC. A total of 294 trees distributed in dbh classes were intentionally selected inside of forest. In each tree was measured dbh, total height, bole height, crown diameter by eight radius, as well as the classification of social position. Simple and multiple linear regression models were used to describe the relation h/d, the proportion of the crown and formal crown in function of diameter at breast height with simple transformation, quadratic, cubic, inverse and logarithmic form. The analysis of covariance with dummy variables were used to describe the social position and tested the parallelism and slope of regression indicating need or not of the use independent regressions. The results indicated that even with great variability in the shape and size of the crown due to growth and competition process, the morphometric relations of araucaria can be accurately estimated by regression models. The relation h/d, proportion of the crown and formal crown can be described by individual model for social position dominant, codominant and dominant, or alternatively a single model with the use of dummy variables that differentiate trees group dominated for the relation h/d and formal crown. The proportion of crown presented difference in dimensions of the trees, being necessary to use dummy variable for each social stratus or use the individual models.

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Background: The microflora hypothesis may be the underlying explanation for the growth of inflammatory disease. In addition to many known affecting factors, knowing the gut microbiota of healthy newborns can help to understand the gut immunity and modulate it. Objectives: This study examined the microbiota of healthy newborns from urban regions. Patients and Methods: We enrolled 128 full-term newborns, born at Seoul St. Mary and St. Paul hospital from January 2009 to February 2010. All 143 samples of feces were cultivated in six culture plates to determine the amounts of total bacteria, anaerobes, gram-positive bacteria, coliforms, lactobacilli, and bifidobacteria. The samples were evaluated with a bivariate correlation between coliforms and lactobacilli. Terminal restriction fragment length polymorphism (T-RFLP) analysis with HhaI and MspI and a clustering analysis were performed for determination of diversity. Results: Bacteria were cultured in 61.5% of feces in the following order: anaerobes, gram-positive bacteria, lactobacilli, coliform, and bifidobacteria. The growth of total bacteria and lactobacilli increased in feces defecated after 24 hours of birth (P < 0.001, P = 0.008) and anaerobes decreased (P = 0.003). A negative correlation between the growth of lactobacilli and coliforms was found (r = -463, P < 0.001). Conclusions: This study confirms that bacterial colonization of healthy newborns born in cities is non-sterile, but has early diversification and inter-individuality.