The forest inventory plays a crucial role in forest management planning, and it is the first step... more The forest inventory plays a crucial role in forest management planning, and it is the first step in planning actions for forest production. However, conducting an inventory can be expensive and complex. Forest inventory applications on smartphones have emerged as an alternative to traditional methods and they aim to make field data collection more accessible to non-professionals while ensuring accuracy in determining the volume of wood in a given area. This study evaluates the effectiveness of the Katam, Arboreal, and Trestima applications compared to traditional data collection methods. The study focuses on assessing the stand density and diameter of sampled trees—two key variables that are assessed in forest inventories. Two species, maritime pine (Pinus pinaster Aiton) and Eucalyptus spp. (mainly Eucalyptus globulus and Eucalyptus nitens), were used to evaluate the performance of the methods, with assessments performed in the stands of diverse dendrometric characteristics, speci...
In recent decades, there has been a perception that the Mozambican forests have been threatened w... more In recent decades, there has been a perception that the Mozambican forests have been threatened with massive exploitation for commercialization, deforesting vast areas, leading to desertification and contributing to the extinction of some forest species. The present research summarizes the official information obtained by monitoring the country’s natural resources over time and identifying the major types of existing forests in Mozambique. The main objective is to elucidate on the current state of Mozambican forests, analyze change and trends, and characterize the actual distribution of forest species in Mozambique to verify the sustainability of forest resources and their composition. It is a case study of the qualitative descriptive type, with data obtained through a bibliographic research method focusing on scientific articles on the type of forest species existing in Africa and Mozambique and data from official sources of the forests. Various types of forests were identified, su...
The growth of sweet cherry cultivars Regina, Skeena and Sweetheart was evaluated when grafted ont... more The growth of sweet cherry cultivars Regina, Skeena and Sweetheart was evaluated when grafted onto the Edabriz rootstock and at four planting densities. The trial was set on March 2003 at four locations in the North and Centre of Portugal, with two replications in Caria, Vila Real and Alcongosta and three in Carrazedo de Montenegro. Within row spacing is approximately 5,0 m and plant spacing along the row is 0.7, 1.4, 2.1 and 2.8 m, corresponding to densities of 2600, 1300, 860 and 650 trees/ha, respectively. The trunk diameter of every plant was measured each year and trunk cross sectional area (TCSA) was calculated. At the end of the second leaf stage, significant differences in growth were already observable, concerning both trial location and plant density. The sweet cherry trees of the C. Montenegro trial grew 76, 36 and 9% more than those of Alcongosta, Vila Real and Caria, respectively, thus trial location accounted for 25% of the expected total variance. Plant density corres...
Quercus rotundifolia Lam., known as holm oak or evergreen oak, occurs naturally in the western Me... more Quercus rotundifolia Lam., known as holm oak or evergreen oak, occurs naturally in the western Mediterranean region, mainly as part of the agroforestry or agrosilvopastoral systems in Portugal (“montado”) and Spain (“dehesa”), and is economically important for acorn production. Less attention has been given to Q. rotundifolia wood, and its density variability is not known, namely related to tree growth. The wood density of 20 Q. rotundifolia trees was measured along the radial direction by X-ray densitometry and the factors responsible for ring width and wood density variation within and between trees were investigated at two sites located within the main species region in southern Portugal. Ring width was significantly different between sites, with an average of 1.81 mm and 1.55 mm. Wood density was very high and averaged between 888 kg/m3 and 914 kg/m3 but not significantly different between sites. Ring width and wood density showed a positive and significant correlation at both s...
Research Highlights: Biomass from Mediterranean agroforestry vegetation may be a potential source... more Research Highlights: Biomass from Mediterranean agroforestry vegetation may be a potential source of renewable energy. However, due to the high heterogeneity of this type of resource, the study of its characteristics becomes necessary for its efficient use. Objectives: The aim of this study was to evaluate the thermal and chemical properties of 14 different kinds of agroforestry biomass groups: shrubs, forest, and agricultural wastes. Materials and Methods: The higher heating value (HHV), the elemental analysis (C, H, O, N, S), ashes, mineral elements (Na, K, Ca, Mg, and P), trace elements (Mn, Fe, Zn, Ni, Cu, Cr, and Cd) and halogen elements (F and Cl) were quantified and compared with CEN/TS 147775 and CENS/TS 14961 standards, looking forward to future use for energy purposes, namely through combustion processes, as an alternative to fossil fuels. Results: The shrubs present the highest values of higher heating value (20.5 MJ kg−1), followed by the forest wastes (19.2 MJ kg−1) and...
With the increase of forest fires in Portugal in recent decades, a significant part of woodlands ... more With the increase of forest fires in Portugal in recent decades, a significant part of woodlands is being converted into shrubland areas. Background: From an ecological point of view, woodlands and shrublands play an essential role, as they not only prevent soil erosion and desertification, but also contribute to soil protection, habitat preservation and restoration, and also increased biodiversity for carbon sequestration. Concerning the shrublands, the assessment of their biomass is essential for evaluating the fuel load and forest fire behavior and also beneficial for obtaining estimates of carbon and biomass for energy use. Methods: In this study, we collected data about the potential shrub biomass accumulation along fifteen years in former burnt areas within North Portugal. Results: The achieved results showed that for a post-fire period ranging from one to 15 years, the accumulated shrubs’ biomass ranged from 0.12 up to 28.88 Mg ha−1. The model developed to estimate the shrub ...
Biomass from forestry and agricultural sector provides an important contribution to encounter the... more Biomass from forestry and agricultural sector provides an important contribution to encounter the government’s targets for increasing bioenergy production and utilization. Characterization of agricultural and forest wastes are critical for exploiting and utilizing them for energy purpose. In the present work agricultural and forest wastes and shrubs were sampled in two sites in north Portugal (Ave and Sabor basin) and subjected to Higher Heating Value (HHV) and chemical composition quantification. The HHV was evaluated according to the methodology described in Standard DD CEN/TS14918:2005. For the lignin content, the procedure was made by the Klason method and the extractives content was determined with the Soxhlet method. For agricultural and forest wastes the HHV values are identical with a range of 17 to 21 MJ·kg−1. However, shrubs biomass presentx slightly higher and statistically different values from agricultural and forest wastes, varying between 19 and 21 MJ·kg−1. Forest was...
Numerical and experimental studies of end-notched flexure (ENF) fracture tests were performed to ... more Numerical and experimental studies of end-notched flexure (ENF) fracture tests were performed to obtain mode II R curves for maritime pine (Pinus pinaster Ait.) wood in the radial-longitudinal (RL) crack propagation system. Three- (3D) and two-dimensional (2D) finite element analyses were conducted to determine the mode II release rate of the critical strain energy (G IIc). The 3D analysis revealed that a small spurious mode III component did not affect G IIc measurements and that the 2D model was very accurate. A new scheme for data reduction based on the equivalent crack concept is proposed to overcome the difficulties related to accurate crack length measurement during propagation. This method does not require previous experimental tests to obtain the elastic modulus, which varies markedly for different wood specimens. Experimental ENF tests were performed to verify the numerical results. The results demonstrate the accuracy of the data reduction method proposed.
The forest inventory plays a crucial role in forest management planning, and it is the first step... more The forest inventory plays a crucial role in forest management planning, and it is the first step in planning actions for forest production. However, conducting an inventory can be expensive and complex. Forest inventory applications on smartphones have emerged as an alternative to traditional methods and they aim to make field data collection more accessible to non-professionals while ensuring accuracy in determining the volume of wood in a given area. This study evaluates the effectiveness of the Katam, Arboreal, and Trestima applications compared to traditional data collection methods. The study focuses on assessing the stand density and diameter of sampled trees—two key variables that are assessed in forest inventories. Two species, maritime pine (Pinus pinaster Aiton) and Eucalyptus spp. (mainly Eucalyptus globulus and Eucalyptus nitens), were used to evaluate the performance of the methods, with assessments performed in the stands of diverse dendrometric characteristics, speci...
In recent decades, there has been a perception that the Mozambican forests have been threatened w... more In recent decades, there has been a perception that the Mozambican forests have been threatened with massive exploitation for commercialization, deforesting vast areas, leading to desertification and contributing to the extinction of some forest species. The present research summarizes the official information obtained by monitoring the country’s natural resources over time and identifying the major types of existing forests in Mozambique. The main objective is to elucidate on the current state of Mozambican forests, analyze change and trends, and characterize the actual distribution of forest species in Mozambique to verify the sustainability of forest resources and their composition. It is a case study of the qualitative descriptive type, with data obtained through a bibliographic research method focusing on scientific articles on the type of forest species existing in Africa and Mozambique and data from official sources of the forests. Various types of forests were identified, su...
The growth of sweet cherry cultivars Regina, Skeena and Sweetheart was evaluated when grafted ont... more The growth of sweet cherry cultivars Regina, Skeena and Sweetheart was evaluated when grafted onto the Edabriz rootstock and at four planting densities. The trial was set on March 2003 at four locations in the North and Centre of Portugal, with two replications in Caria, Vila Real and Alcongosta and three in Carrazedo de Montenegro. Within row spacing is approximately 5,0 m and plant spacing along the row is 0.7, 1.4, 2.1 and 2.8 m, corresponding to densities of 2600, 1300, 860 and 650 trees/ha, respectively. The trunk diameter of every plant was measured each year and trunk cross sectional area (TCSA) was calculated. At the end of the second leaf stage, significant differences in growth were already observable, concerning both trial location and plant density. The sweet cherry trees of the C. Montenegro trial grew 76, 36 and 9% more than those of Alcongosta, Vila Real and Caria, respectively, thus trial location accounted for 25% of the expected total variance. Plant density corres...
Quercus rotundifolia Lam., known as holm oak or evergreen oak, occurs naturally in the western Me... more Quercus rotundifolia Lam., known as holm oak or evergreen oak, occurs naturally in the western Mediterranean region, mainly as part of the agroforestry or agrosilvopastoral systems in Portugal (“montado”) and Spain (“dehesa”), and is economically important for acorn production. Less attention has been given to Q. rotundifolia wood, and its density variability is not known, namely related to tree growth. The wood density of 20 Q. rotundifolia trees was measured along the radial direction by X-ray densitometry and the factors responsible for ring width and wood density variation within and between trees were investigated at two sites located within the main species region in southern Portugal. Ring width was significantly different between sites, with an average of 1.81 mm and 1.55 mm. Wood density was very high and averaged between 888 kg/m3 and 914 kg/m3 but not significantly different between sites. Ring width and wood density showed a positive and significant correlation at both s...
Research Highlights: Biomass from Mediterranean agroforestry vegetation may be a potential source... more Research Highlights: Biomass from Mediterranean agroforestry vegetation may be a potential source of renewable energy. However, due to the high heterogeneity of this type of resource, the study of its characteristics becomes necessary for its efficient use. Objectives: The aim of this study was to evaluate the thermal and chemical properties of 14 different kinds of agroforestry biomass groups: shrubs, forest, and agricultural wastes. Materials and Methods: The higher heating value (HHV), the elemental analysis (C, H, O, N, S), ashes, mineral elements (Na, K, Ca, Mg, and P), trace elements (Mn, Fe, Zn, Ni, Cu, Cr, and Cd) and halogen elements (F and Cl) were quantified and compared with CEN/TS 147775 and CENS/TS 14961 standards, looking forward to future use for energy purposes, namely through combustion processes, as an alternative to fossil fuels. Results: The shrubs present the highest values of higher heating value (20.5 MJ kg−1), followed by the forest wastes (19.2 MJ kg−1) and...
With the increase of forest fires in Portugal in recent decades, a significant part of woodlands ... more With the increase of forest fires in Portugal in recent decades, a significant part of woodlands is being converted into shrubland areas. Background: From an ecological point of view, woodlands and shrublands play an essential role, as they not only prevent soil erosion and desertification, but also contribute to soil protection, habitat preservation and restoration, and also increased biodiversity for carbon sequestration. Concerning the shrublands, the assessment of their biomass is essential for evaluating the fuel load and forest fire behavior and also beneficial for obtaining estimates of carbon and biomass for energy use. Methods: In this study, we collected data about the potential shrub biomass accumulation along fifteen years in former burnt areas within North Portugal. Results: The achieved results showed that for a post-fire period ranging from one to 15 years, the accumulated shrubs’ biomass ranged from 0.12 up to 28.88 Mg ha−1. The model developed to estimate the shrub ...
Biomass from forestry and agricultural sector provides an important contribution to encounter the... more Biomass from forestry and agricultural sector provides an important contribution to encounter the government’s targets for increasing bioenergy production and utilization. Characterization of agricultural and forest wastes are critical for exploiting and utilizing them for energy purpose. In the present work agricultural and forest wastes and shrubs were sampled in two sites in north Portugal (Ave and Sabor basin) and subjected to Higher Heating Value (HHV) and chemical composition quantification. The HHV was evaluated according to the methodology described in Standard DD CEN/TS14918:2005. For the lignin content, the procedure was made by the Klason method and the extractives content was determined with the Soxhlet method. For agricultural and forest wastes the HHV values are identical with a range of 17 to 21 MJ·kg−1. However, shrubs biomass presentx slightly higher and statistically different values from agricultural and forest wastes, varying between 19 and 21 MJ·kg−1. Forest was...
Numerical and experimental studies of end-notched flexure (ENF) fracture tests were performed to ... more Numerical and experimental studies of end-notched flexure (ENF) fracture tests were performed to obtain mode II R curves for maritime pine (Pinus pinaster Ait.) wood in the radial-longitudinal (RL) crack propagation system. Three- (3D) and two-dimensional (2D) finite element analyses were conducted to determine the mode II release rate of the critical strain energy (G IIc). The 3D analysis revealed that a small spurious mode III component did not affect G IIc measurements and that the 2D model was very accurate. A new scheme for data reduction based on the equivalent crack concept is proposed to overcome the difficulties related to accurate crack length measurement during propagation. This method does not require previous experimental tests to obtain the elastic modulus, which varies markedly for different wood specimens. Experimental ENF tests were performed to verify the numerical results. The results demonstrate the accuracy of the data reduction method proposed.
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Papers by José Luis Lousada