Fonte: Universidade de Trás-os-Montes e Alto DouroPublicador: Universidade de Trás-os-Montes e Alto Douro
Tipo: Tese de Doutorado
Relevância na Pesquisa
Tese de Doutoramento em Ciências Florestais; Pinus pinaster Ait. é uma das mais importantes espécies florestais Portuguesas, ocupando 23% da área florestal nacional. Dada a sua importância económica no país, foi implementado um programa de melhoramento no início dos anos 80. Este programa está presentemente na sua 2ª geração de selecção, sendo que o ensaio utilizado no presente estudo é parte desse programa. Esta tese teve como principal objectivo o estudo do controlo genético de algumas das mais importantes propriedades da madeira da P. pinaster, dando especial atenção às relações genéticas entre as características e entre estas e os parâmetros de crescimento. Pretendeu-se com este trabalho contribuir para o programa de melhoramento da P. pinaster, adicionando informação sobre a qualidade da madeira de 46 famílias de polinização livre pertencentes à 1ª geração deste programa, representadas num ensaio que foi alvo de um incêndio no ano de 2003. Os resultados obtidos indicam que a densidade média do anel foi a característica estudada que apresentou valores mais elevados de heritabilidade (ℎ=0.63). Os resultados obtidos indicam que nas condições mediterrâneas as características do lenho inicial estão sujeitas a maior controlo genético (ℎ(MND)=0.54...
Not all wildfire ignitions result in burned
areas of a similar size. The aim of this study was to
explore whether there was a size-dependent pattern
(in terms of resulting burned area) of fire ignitions in
Portugal. For that purpose we characterised 71,618
fire ignitions occurring in the country in the period
2001–2003, in terms of population density in the
local parish, land cover type and distance to roads.
We then assigned each ignition into subsets of five
classes according to the resulting burned area:[5 ha,
[50 ha,[100 ha,[250 ha,[500 ha. The probability
of an ignition resulting in different burned area
classes was modelled using binary logistic regression,
and the relative importance, strength and signal
(positive or negative) of the three explanatory
variables compared across the models obtained for
the different classes. Finally, we explored the implications
of land cover and population density changes
during the period 1990–2000 in Portugal for the
likelihood of ignitions resulting in wildfires[500 ha.
Population density was the more important variable
explaining the resulting burned area, with the probability of an ignition resulting in a large burned
area being inversely related to population density. In
terms of land cover...
Doutoramento em Engenharia Florestal - Instituto Superior de Agronomia; The recent awareness to what would be the climate change consequences, namely in the
observed changes in the fire regimes, highlight the urgency for piro-climatic studies. The lack of
an historical burnt area dataset to complement recent products, covering the global extent and its
full variability,makes it difficult to detect significant trends. Due to the lack of global information
before year-2000, a burned area product based on the NOAA Pathfinder AVHRR land (8km) dataset
was developed covering the period from 1981 to 1999. As reference we screened the World
Fire Atlas dataset, by removing all the non wildfires and false alarm information and we addressed
the expected detectable area made by the coarser sensor. Data pre-processing was prefomed
by removing the satellite orbital drift trends with empirical mode decomposition and a burned
area classification was done based on the Random Forest classification algorithm. Although the
developed methodologies allowed to overcome many of the technical difficulties and the results
showed high flexibility to cover the full extent of possible fire occurrences, burned areas were
characterised by large underestimation. This is mainly explained by the PAL re-sampling procedure
and by the limitations of the coarser sensor to detect certain burned scar spatial patterns.
This study was designed to evaluate the frequency and profile of bloodstream infection (BSI) in a burn intensive care unit (BICU) in Tripoli, Libya, from 1st January 2000 to 31st December 2007 and to determine the prevalence of different bacteria involved in such infections and their antimicrobial susceptibilities. During the eight-year study period, 995 patients were admitted to the BICU. Blood cultures were collected from each septicaemic case and reviewed for age, sex, total body surface area burned, isolated micro-organisms, and antibiotic sensitivity. There were 430 episodes of BSI among 830 cases; the annual true positive rate varied between 40.0 and 59.4%, the majority (87.9%) being caused by one species only. However, 22% had two or more episodes with different pathogens during hospitalization. The leading isolate was
aureus (40.4%) (methicillinresistant, 55.7%).
Pseudomonas spp ranked second (23.9%).
Klebsiella spp were third, responsible for 7.4%; the rate of extended spectrum beta lactamase among
Klebsiella isolates was 47%.
Candida spp were the fourth most common pathogen (6.7%), the majority (55%) being C. albicans.
Staphylococci were generally resistant to trimethoprim (91%) and fusidic acid (80%).
Pseudomonas spp proved moderately resistant (38-43%) to tobramicin...
The term “fourth-degree burn” is not very often found in the literature because it is often associated with lethal injury. These injuries are characterized by exposure of viable tissue such as tendon or bone and are associated with challenging wound closure. The goal of reconstruction is to provide adequate soft tissue coverage and restoration of function. Several treatment modalities have been used to serve this purpose. We present four male patients with fourth-degree burns of the extremities, treated with negative pressure wound therapy. The patients’ age ranged from 15 to 49 yr (mean, 28 yr). The total body surface area burned ranged from 3 to 60% (mean, 34.25%). Negative pressure wound therapy was applied for 16-30 days (mean, 23.75 days). Three split-thickness skin grafts and one bipedicled local flap were performed. Wound closure was completed in 28 to 50 days. The results were satisfactory for both physicians and patients. Our longest follow-up was three years. The results achieved in this group of patients revealed the negative pressure wound therapy was a reliable alternative method in the treatment of fourthdegree burns.
Dry forests at low elevations in temperate-zone mountains are commonly hypothesized to be at risk of exceptional rates of severe fire from climatic change and land-use effects. Their setting is fire-prone, they have been altered by land-uses, and fire severity may be increasing. However, where fires were excluded, increased fire could also be hypothesized as restorative of historical fire. These competing hypotheses are not well tested, as reference data prior to widespread land-use expansion were insufficient. Moreover, fire-climate projections were lacking for these forests. Here, I used new reference data and records of high-severity fire from 1984–2012 across all dry forests (25.5 million ha) of the western USA to test these hypotheses. I also approximated projected effects of climatic change on high-severity fire in dry forests by applying existing projections. This analysis showed the rate of recent high-severity fire in dry forests is within the range of historical rates, or is too low, overall across dry forests and individually in 42 of 43 analysis regions. Significant upward trends were lacking overall from 1984–2012 for area burned and fraction burned at high severity. Upward trends in area burned at high severity were found in only 4 of 43 analysis regions. Projections for A.D. 2046–2065 showed high-severity fire would generally be still operating at...
No presente trabalho pretende-se analisar a distribuição espacial e detetar tendências de evolução, no período de 1980 a 2012, na densidade de ignições e na percentagem de áreas ardidas, a nível distrital. Os resultados referentes à densidade de ignições são perentórios quanto ao seu acréscimo, pois em todas as unidades territoriais os coeficientes de Pearson e Spearman revelam-se estatisticamente significativos. No que se refere às percentagens de superfície média incinerada, os resultados são mais díspares. Com tendências positivas (p-value <0,05), sobressaem todos os distritos da região Norte, enquanto os de Beja e Évora manifestam a mesma tendência, apenas se aplicado o coeficiente de Spearman. Com tendência inversa, isto é, de decréscimo, apenas se destaca Coimbra. Nos restantes distritos as tendências observadas não revelam significado estatístico (p-value >0,05).; In this work we aim to analyze the spatial distribution and to detect trends in the density of ignitions and in
the percentage of burnt areas, for the period 1980-2012, at district level. Concerning to the density of ignitions, the results obtained show a significant positive trend for all the territorial units, when Pearson and Spearman coefficients were applied. As regards to the mean annual percentages of surface incinerated...
The aim of the study was to investigate the factors affecting the outcome of treatment of burns patients admitted to the Burns Intensive Care Unit (BICU) of the Komfo Anokye Teaching Hospital, Kumasi, Ghana. Information on patients admitted to the BICU from February 2001 to January 2006 was recorded. Parameters recorded included: admission record and demographics, causes of the injury, burned surface area, laboratory investigations, treatment regime, and record of discharge/death. The data were analysed with SPSS version 12.0 and Spearman's rank correlation. A total of 826 patients were recorded; males (n = 492, 60%) outnumbered females (n= 334, 40%). The mean age was 10.5 ± 5 yr, the majority (n = 441, 53%) in the range 0-10 yr. Flame burns (n = 587, 71%), scalds (n = 209, 25%), and chemicals (n = 19, 2%) were the three significant causes of burn injuries. The mean range of the total body surface area (TBSA) burned was 11-20%; 94% (n = 775) had up to 60% TBSA; 64% (n = 527) had only wound dressings for treatment; 21% (n = 174) had early excision with skin grafting, while 15% (n = 125) had delayed excision with skin grafting. The majority (n = 563, 68%) of the patients stayed for less than 10 days after admission. The mortality rate fell over the years...
Fragmentation of lowland peatswamp forests in Borneo poses a serious threat to the endangered Bornean orang-utan, whose decreasing population trends are attributed primarily to habitat loss. The orang-utan is projected to be extinct by 2020 unless existing populations can be connected and new conservation areas established, which is not currently economically viable. However, peatswamp forests, on which orang-utans can be found at their greatest densities, have a large capacity for carbon sequestration and storage and, thus, a high potential value on the carbon market. Unfortunately, as these wetlands are being deforested, drained, and burned for development, the peat soil is decomposing, emitting CO2, and impacting global climate change. This project is a spatially explicit analysis of an area of fragmented peatswamp forest in Central Kalimantan, Indonesia that explores how the conservation targets of ape preservation and carbon sequestration and storage can be mutually satisfied through land management strategies. First, I prioritized intact peatswamp forest patches for conservation based on orang-utan presence and patch geometry metrics. To do this, I surveyed line transects in the study area, Block C of the Former Mega Rice Project...
Located in Western North Carolina, Linville Gorge Wilderness Area has an extensive fire history that has been characterized by burns of variable size and severity. Beginning in the 1940s, an era of burn suppression policies curtailed the Gorge’s established fire regime. Local stakeholders, including The Wilderness Society (TWS) and the U.S. Forest Service, are concerned about the effects of burn suppression on fire dependent species and communities. As such, these groups are interested in following a modern resurgence of anthropogenic wildfires with a prescribed fire program. Many sampling efforts since 1992 have studied permanent vegetation plots spread throughout Linville Gorge to characterize local plant communities and their relationship with five recent fires. With my Master’s Project, done for The Wilderness Society, two objectives related to fire in the Gorge are addressed. First, structural and compositional trends in Linville Gorge forests have been identified, and those trends have been overlain with geospatial environmental variables as well as remotely sensed fire severity estimations. Second, wildfires have been evaluated for their meeting of restoration goals. TWS’s restoration targets include a reduction in the importance of ericaceous and fire intolerant species...
Global warming is likely modifying the hydrological cycle of forested watersheds. This report set as objectives to: a) assess the hydrological variables interception loss, I, potential and actual evapo-transpiration, E, Et, runoff, Q, and soil moisture content, θ; b) evaluate whether these variables are presenting consistent trends or oscillations that can be associated to global warming or climate variability; and c) relate θ to the number of wildfires and the burned area in Durango, Mexico. A mass balance approach estimated daily variables of the water cycle using sub-models for I and Et to calculate Q and θ for a time series from 1945 to 2007. Regression and auto-regressive and moving averaging (ARIMA) techniques evaluated the statistical significance of trends. The cumulative standardized z value magnified and ARIMA models projected statistically similar monthly and annual time series data of all variables of the water cycle. Regression analysis and ARIMA models showed monthly and annual P, I, E, and Et, Q, and θ do not follow consistent up or downward linear tendencies over time with statistical significance; they rather follow oscillations that could be adequately predicted by ARIMA models (r² ≥ 0.70). There was a consistent statistical association (p ≤ 0.05) of θ with the number of wildfires and the area burned regardless of the different spatial scales used in evaluating these variables. The analysis shows seasonal variability is increasing over time as magnifying pulses of dryness and wetness...