Santos A.,University of Lisbon |
Santos A.,Research Center for Natural Resources |
Anjos O.,Polytechnic Institute of Castelo Branco |
Anjos O.,Research Center for Natural Resources |
And 4 more authors.
Journal of Wood Science | Year: 2012
Wood density and pulp yield are key parameters in the evaluation of tree productivity and quality for pulping and their relationships are of high practical importance. The influence of wood density on pulp yield and other pulp quality parameters was investigated using Acacia melanoxylon and its natural variability as a case study. Twenty trees were harvested (five trees in each of four sites in Portugal), and wood discs taken at different height levels, from the base to the top of the tree, providing 100 wood samples, covering the natural variability of wood density ranging from 449 kg m-3 to 649 kg m-3. Under the same experimental conditions of kraft pulping, screened pulp yield ranged 47. 0-58. 2 %, Kappa number 10. 9-18. 4, ISO brightness 14. 9-45. 6, fibre length 0. 660-0. 940 mm and fibre width 16. 2-22. 9 μm. The pulp yield and Kappa number were not correlated with wood density. Higher pulp yields were associated with lower Kappa numbers and alkali consumption, suggesting the important role of chemical composition of wood on kraft cooking. The results confirm the high pulping potential of Acacia melanoxylon trees grown in Portugal and suggest the possibility of tree selection using both wood density and pulp yield. © 2012 The Japan Wood Research Society.
REIS C.M.G.,Polytechnic Institute of Castelo Branco |
REIS C.M.G.,Research Center for Natural Resources |
GAZARINI L.C.,University of Évora |
FONSECA T.F.,University of Trás os Montes e Alto Douro |
And 2 more authors.
Experimental Agriculture | Year: 2016
In marginal lands Opuntia ficus-indica (OFI) could be used as an alternative fruit and forage crop. The plant vigour and the biomass production were evaluated in Portuguese germplasm (15 individuals from 16 ecotypes) by non-destructive methods, 2 years following planting in a marginal soil and dryland conditions. Two Italian cultivars (Gialla and Bianca) were included in the study for comparison purposes. The biomass production and the plant vigour were estimated by measuring the cladodes number and area, and the fresh (FW) and dry weight (DW) per plant. We selected linear models by using the biometric data from 60 cladodes to predict the cladode area, the FW and the DW per plant. Among ecotypes, significant differences were found in the studied biomass-related parameters and several homogeneous groups were established. Four Portuguese ecotypes had higher biomass production than the others, 3.20 Mg ha−1 on average, a value not significantly different to the improved ‘Gialla’ cultivar, which averaged 3.87 Mg ha−1. Those ecotypes could be used to start a breeding program and to deploy material for animal feeding and fruit production. Copyright © Cambridge University Press 2016
J. Lourenco E.,Campus Management |
J. Baptista A.,Campus Management |
P. Pereira J.,Campus Management |
Dias-Ferreira C.,Research Center for Natural Resources
Re-Engineering Manufacturing for Sustainability - Proceedings of the 20th CIRP International Conference on Life Cycle Engineering | Year: 2013
Nowadays achieving sustainable development is a global concern. The issue of unsustainability can be related to population growth and excessive consumption of natural resources. To tackle these issues, several management tools and methodologies have been developed in the last years, to assess, analyse and improve the environmental and economic performance of production systems. This work presents an approach based value stream mapping in order to assess and improve energy efficiency, environmental performance and financial performance of a production system. The developed approach can be applied to any industry or production system, where all the unit processes involved are identified and the inputs/outputs of each unit system quantified and easily perceived. Key environmental performance indicators and the corresponding eco-efficiency ratios arise as outcomes of this approach, in which a Multi-Layer Stream Mapping (MSM) with visual management attributes is created.
Gomes H.I.,New University of Lisbon |
Gomes H.I.,Research Center for Natural Resources |
Dias-Ferreira C.,Research Center for Natural Resources |
Ribeiro A.B.,New University of Lisbon
Science of the Total Environment | Year: 2013
Polychlorinated biphenyls (PCB) are persistent organic pollutants used worldwide between the 1930s and 1980s. Although their use has been heavily restricted, PCB can be found in contaminated soils and sediments. The most frequent remediation solutions adopted are "dig and dump" and "dig and incinerate", but there are currently new methods that could be more sustainable alternatives. This paper takes a look into the remediation options available for PCB-contaminated soils and sediments, differentiating between biological, chemical, physical and thermal methods. The use of combined technologies was also reviewed. Most of them are still in an initial development stage and further research in different implementation issues is needed. There is no single technology that is the solution for PCB contamination problem. The successful remediation of a site will depend on proper selection, design and adjustment of the technology or combined technologies to the site characteristics. © 2012 Elsevier B.V.
Soares M.A.R.,University of Coimbra |
Soares M.A.R.,Research Center for Natural Resources |
Quina M.J.,University of Coimbra |
Quinta-Ferreira R.M.,University of Coimbra
Journal of Environmental Management | Year: 2015
This study aims to evaluate the capacity of a compost obtained by co-composting of industrial eggshell (CES) to immobilise lead (Pb) and zinc (Zn) in an acidic soil contaminated by mining activities. Mature compost without eggshell (CWES) and natural eggshell (ES) were also tested as soil amendments for comparison purposes. Three different application rates were used for each material, ensuring the same quantity in terms of neutralizing capacity. Incubation experiments were conducted under controlled conditions and CO2 emissions monitored for 94 days. The environmental availability of Pb and Zn in the amended soil was assessed and bioassays were performed at the end of the incubation period.When eggshells were present, the CES compost raised the soil pH to values higher than 6 and reduced the soil mobile fraction for both Pb and Zn, in more than 95%. Soil toxicity towards Vibrio fischeri was also suppressed and environmental risk decreased to "low level". However, the immobilisation in the acid insoluble soil component was significantly achieved only for Zn. In addition, regarding soil carbon dynamics the CO2-C emissions were enhanced, mainly in the case of the highest rate of amendment. Both first order-E and parallel first order models may adequately describe the kinetic data of CO2-C cumulative release. Without eggshells, the CWES compost revealed limited effect on heavy metals immobilisation, likely due to its small capacity to correct soil acidity, at lower application rates. Using solely eggshells, the ES waste had similar outcomes when compared with CES, but at the higher application rate, CO2 emissions were enhanced with the eggshell compost due to the contribution of biotic carbon present therein. Therefore, this study points out that CES is an effective liming material and may be used for in situ remediation of contaminated soil with Pb and Zn. © 2015 Elsevier Ltd.