The present work has as overall objective to evaluate the suitability of two easily-applied erosi... more The present work has as overall objective to evaluate the suitability of two easily-applied erosion models for slope-scale erosion risk mapping, using a Geographic Information System, following wildfire. It was carried out in the framework of the EROSFIRE project, which, in a nutshell, wants to assess the advantages and disadvantages of field rainfall simulation experiments for mapping erosion risk, in particular by providing the input data needed for model calibration. The Universal Soil Loss Equation (USLE) and the Morgan-Morgan-Finney model (MMF) were selected in this study mainly for ease of application. In spite both models were specifically developed for agricultural fields, there exist off-the-shelf model parameter values that apparently or supposedly are suitable for recently burnt forest areas. Furthermore, USLE was applied by the Portuguese National Water Institute following the dramatic wildfire season of the summer of 2003 and, as such, was a lead motif behind the EROSFI...
Wildfires can cause significant changes to hydrological and soil erosion processes, through the d... more Wildfires can cause significant changes to hydrological and soil erosion processes, through the destruction of vegetation cover and changes to soil properties. Modeling soil erosion in burnt areas is still a challenge, since most erosion models are built for agricultural fields and usually present a poor performance when applied to burnt areas. An important fact behind the poor performance is that important processes, such as the onset and destruction of soil water repellence or the transport of litter and ash, are not well represented in most models. Project EROSFIRE aims to develop a soil erosion model to be applied in burnt hillslopes. For this purpose, the project collected data on six burnt hillslopes in central Portugal. Measurements included weekly runoff and sediment collection and bi-weekly transects detailing vegetation cover, ash cover and soil water repellence on different points along the hillslope. At the same time, rainfall simulation experiments were conducted near t...
t e r r i t o r i u m Revista da Associação Portuguesa de Riscos, Prevenção e Segurança 2009 16 R... more t e r r i t o r i u m Revista da Associação Portuguesa de Riscos, Prevenção e Segurança 2009 16 RISCOS A.P.R.P.S. t e r r i t o r i u m 16
A retrospective study was made of the requests for bacteriological examination of urine samples b... more A retrospective study was made of the requests for bacteriological examination of urine samples by the different clinical departments of Vila Nova de Famalicão District Hospital, between July/89-June/90 and July/91-June/92. We were interested in assessing the spectrum of occurring micro-organisms in urinary tract infections, their antibiotic susceptibility, especially to those more frequently used in clinical practice in this institution and their evolution in time. In conclusion, the prevalence of isolated pathogens was quite similar to the spectrum published by other authors for a hospital population. No significant variation was found in the bacterial population between the two periods analysed, if we exclude the great increase in coagulase-negative staphylococci. In terms of benefits/costs/resistance, we concluded that the best antibiotic for the beginning of therapy in this Hospital is cotrimoxazole. Good choices were also quinolones, third-generation cephalosporins or aminogly...
The EROSFIRE project (POCI/AGR/60354/2004), funded by Portugal's Foundation for Science and Techn... more The EROSFIRE project (POCI/AGR/60354/2004), funded by Portugal's Foundation for Science and Technology (FCT), has as overall aim the development of a software tool that allows to assess and map, at the scale of individual hill slopes, soil erosion hazard in recently burned forest areas for different scenarios of post-fire land management. At the origin of the EROSFIRE project was the ''Soil losses after the forest fires of the summer of 2003''-map elaborated by Portugal's Water Institute (INAG) using some modified version of the Universal Soil Loss Equation (USLE), and the idea to test the applicability of erosion models with a more up-to-date scientific basis than USLE.
Abstract. Soil water repellency is now known,to occur in diverse soils in various parts of the wo... more Abstract. Soil water repellency is now known,to occur in diverse soils in various parts of the world. One of the possible adverse effects of soil water repellency is that it can reduce infiltration capacity and hence, on sloping terrain, enhance overland flow and soil erosion. The main aim of the present work is to assess the effects of soil water
Certain organic compounds derived from living organisms or their decaying parts are generally acc... more Certain organic compounds derived from living organisms or their decaying parts are generally accepted to induce soil water repellency. Water repellency may therefore be expected to increase with proximity to organisms releasing hydrophobic compounds. This hypothesis is tested here for Eucalyptus globulus trees, since eucalypt species are frequently associated with elevated repellency levels. In a young, first-rotation plantation on coastal dune sands in central Portugal, repeat measurements of water repellency using the 'Molarity of an Ethanol Droplet' (MED) test were carried out in situ between April 2001 and May 2002. On 25 dates, repellency was measured at initially 2 and later 3 distances on 2 sides of 8-11 randomly selected trees. On 15 occasions, additional repellency measurements were performed within small grids aside 3 of the selected trees.
Vegetation or, to be more precise, the lack of it is widely regarded to play a key role in enhanc... more Vegetation or, to be more precise, the lack of it is widely regarded to play a key role in enhanced overland flow generation and associated sediment losses following wildfires. Nonetheless, as pointed out by Shakesby and Doerr (2006) in their review paper on wildfire as a hydrological and geomorphological agent, there continues to be a need to further untangle the effects of vegetation destruction and its post-fire recovery from those of the fire-induced changes in other factors, of which soil water repellency has received particular research attention. This is an all but trivial task, however, especially under field conditions, since post-fire changes in potentially influencing factors can be expected to correlate with time after fire and, thus, with each other, even if these factors are in fact themselves unrelated. Post-fire erosion control measures commonly aim at decreasing bare soil cover and, thereby, are perhaps easily taken to invoke the role of vegetation in reducing erosi...
HYDROLOGICAL PROCESSES Hydrol. Process. 21, 23172324 (2007) Published online in Wiley InterScien... more HYDROLOGICAL PROCESSES Hydrol. Process. 21, 23172324 (2007) Published online in Wiley InterScience (www.interscience.wiley.com) DOI: 10.1002/hyp.6756 ... Temporal and spatial variations in topsoil water repellency ... JJ Keizer,1* SH Doerr,2 MC Malvar,1 AJD ...
The EROSFIRE project (POCI/AGR/60354/2004), funded by Portugal's Foundation for Science and Techn... more The EROSFIRE project (POCI/AGR/60354/2004), funded by Portugal's Foundation for Science and Technology (FCT), has as overall aim the development of a software tool that allows to assess and map, at the scale of individual hill slopes, soil erosion hazard in recently burned forest areas for different scenarios of post-fire land management. At the origin of the EROSFIRE project was the ''Soil losses after the forest fires of the summer of 2003''-map elaborated by Portugal's Water Institute (INAG) using some modified version of the Universal Soil Loss Equation (USLE), and the idea to test the applicability of erosion models with a more up-to-date scientific basis than USLE.
The aim of this study was to improve the existing knowledge of the runoff and inter-rill erosion ... more The aim of this study was to improve the existing knowledge of the runoff and inter-rill erosion response of forest stands following wildfire, focusing on commercial eucalypt plantations and employing field rainfall simulation experiments (RSE's). Repeated RSE's were carried out in two adjacent but contrasting eucalypt stands on steep hill slopes in north-central Portugal that suffered a moderate severity fire in July 2005. This was done at six occasions ranging from 3 to 24 months after the fire and using a paired-plot experimental design that comprised two pairs of RSE's at each site and occasion. Of the 46 RSE's: (i) 24 and 22 RSE's involved application rates of 45-50 and 80-85 mm h À 1 , respectively; (ii) 22 took place in a stand that had been ploughed in down slope direction several years before the wildfire and 24 in an unploughed stand.
The aim of this study is to improve our knowledge of the temporal and spatial variations of soil ... more The aim of this study is to improve our knowledge of the temporal and spatial variations of soil water repellency following wildfire, in particular for the eucalypt stands that now dominate the landscape of north-central Portugal.
The EROSFIRE project selected field rainfall simulation experiments (RSE's) as a time-and co... more The EROSFIRE project selected field rainfall simulation experiments (RSE's) as a time-and cost-effective approach to gather runoff and soil loss data under the rapidly changing conditions typical for commercial eucalypt plantations in Portugal following wildfires. These RSE ...
Post-fire erosion has been an important issue in recent years due to the increasing number of fir... more Post-fire erosion has been an important issue in recent years due to the increasing number of fires. Monitoring post-fire erosion in this study is part of the EROSFIRE project (POCI/AGR/60354/2004), funded by the Por-tuguese Foundation for Science and ...
... João Pedro Nunes, Maruxa Malvar, and Jan Jacob Keizer CESAM & Dept. ... empirical mod... more ... João Pedro Nunes, Maruxa Malvar, and Jan Jacob Keizer CESAM & Dept. ... empirical model predicting soil water repellency for recently burnt eucalypt stands in central Portugal, and its incorporation in the surface runoff component of the Morgan-Morgan-Finney (MMF) erosion ...
Since the late summer of 2005, the EROSFIRE project is investigating the hydrological and soil er... more Since the late summer of 2005, the EROSFIRE project is investigating the hydrological and soil erosion response in recently burnt eucalypt plantations. The study areas are located in the municipalities of Águeda, Albergaria-a-Velha and Sever de Vouga, at reasonably close distances from the project's home base at the University of Aveiro, which has allowed carrying out intensive field campaigns and,
The present work has as overall objective to evaluate the suitability of two easily-applied erosi... more The present work has as overall objective to evaluate the suitability of two easily-applied erosion models for slope-scale erosion risk mapping, using a Geographic Information System, following wildfire. It was carried out in the framework of the EROSFIRE project, which, in a nutshell, wants to assess the advantages and disadvantages of field rainfall simulation experiments for mapping erosion risk, in particular by providing the input data needed for model calibration. The Universal Soil Loss Equation (USLE) and the Morgan-Morgan-Finney model (MMF) were selected in this study mainly for ease of application. In spite both models were specifically developed for agricultural fields, there exist off-the-shelf model parameter values that apparently or supposedly are suitable for recently burnt forest areas. Furthermore, USLE was applied by the Portuguese National Water Institute following the dramatic wildfire season of the summer of 2003 and, as such, was a lead motif behind the EROSFI...
Wildfires can cause significant changes to hydrological and soil erosion processes, through the d... more Wildfires can cause significant changes to hydrological and soil erosion processes, through the destruction of vegetation cover and changes to soil properties. Modeling soil erosion in burnt areas is still a challenge, since most erosion models are built for agricultural fields and usually present a poor performance when applied to burnt areas. An important fact behind the poor performance is that important processes, such as the onset and destruction of soil water repellence or the transport of litter and ash, are not well represented in most models. Project EROSFIRE aims to develop a soil erosion model to be applied in burnt hillslopes. For this purpose, the project collected data on six burnt hillslopes in central Portugal. Measurements included weekly runoff and sediment collection and bi-weekly transects detailing vegetation cover, ash cover and soil water repellence on different points along the hillslope. At the same time, rainfall simulation experiments were conducted near t...
t e r r i t o r i u m Revista da Associação Portuguesa de Riscos, Prevenção e Segurança 2009 16 R... more t e r r i t o r i u m Revista da Associação Portuguesa de Riscos, Prevenção e Segurança 2009 16 RISCOS A.P.R.P.S. t e r r i t o r i u m 16
A retrospective study was made of the requests for bacteriological examination of urine samples b... more A retrospective study was made of the requests for bacteriological examination of urine samples by the different clinical departments of Vila Nova de Famalicão District Hospital, between July/89-June/90 and July/91-June/92. We were interested in assessing the spectrum of occurring micro-organisms in urinary tract infections, their antibiotic susceptibility, especially to those more frequently used in clinical practice in this institution and their evolution in time. In conclusion, the prevalence of isolated pathogens was quite similar to the spectrum published by other authors for a hospital population. No significant variation was found in the bacterial population between the two periods analysed, if we exclude the great increase in coagulase-negative staphylococci. In terms of benefits/costs/resistance, we concluded that the best antibiotic for the beginning of therapy in this Hospital is cotrimoxazole. Good choices were also quinolones, third-generation cephalosporins or aminogly...
The EROSFIRE project (POCI/AGR/60354/2004), funded by Portugal's Foundation for Science and Techn... more The EROSFIRE project (POCI/AGR/60354/2004), funded by Portugal's Foundation for Science and Technology (FCT), has as overall aim the development of a software tool that allows to assess and map, at the scale of individual hill slopes, soil erosion hazard in recently burned forest areas for different scenarios of post-fire land management. At the origin of the EROSFIRE project was the ''Soil losses after the forest fires of the summer of 2003''-map elaborated by Portugal's Water Institute (INAG) using some modified version of the Universal Soil Loss Equation (USLE), and the idea to test the applicability of erosion models with a more up-to-date scientific basis than USLE.
Abstract. Soil water repellency is now known,to occur in diverse soils in various parts of the wo... more Abstract. Soil water repellency is now known,to occur in diverse soils in various parts of the world. One of the possible adverse effects of soil water repellency is that it can reduce infiltration capacity and hence, on sloping terrain, enhance overland flow and soil erosion. The main aim of the present work is to assess the effects of soil water
Certain organic compounds derived from living organisms or their decaying parts are generally acc... more Certain organic compounds derived from living organisms or their decaying parts are generally accepted to induce soil water repellency. Water repellency may therefore be expected to increase with proximity to organisms releasing hydrophobic compounds. This hypothesis is tested here for Eucalyptus globulus trees, since eucalypt species are frequently associated with elevated repellency levels. In a young, first-rotation plantation on coastal dune sands in central Portugal, repeat measurements of water repellency using the 'Molarity of an Ethanol Droplet' (MED) test were carried out in situ between April 2001 and May 2002. On 25 dates, repellency was measured at initially 2 and later 3 distances on 2 sides of 8-11 randomly selected trees. On 15 occasions, additional repellency measurements were performed within small grids aside 3 of the selected trees.
Vegetation or, to be more precise, the lack of it is widely regarded to play a key role in enhanc... more Vegetation or, to be more precise, the lack of it is widely regarded to play a key role in enhanced overland flow generation and associated sediment losses following wildfires. Nonetheless, as pointed out by Shakesby and Doerr (2006) in their review paper on wildfire as a hydrological and geomorphological agent, there continues to be a need to further untangle the effects of vegetation destruction and its post-fire recovery from those of the fire-induced changes in other factors, of which soil water repellency has received particular research attention. This is an all but trivial task, however, especially under field conditions, since post-fire changes in potentially influencing factors can be expected to correlate with time after fire and, thus, with each other, even if these factors are in fact themselves unrelated. Post-fire erosion control measures commonly aim at decreasing bare soil cover and, thereby, are perhaps easily taken to invoke the role of vegetation in reducing erosi...
HYDROLOGICAL PROCESSES Hydrol. Process. 21, 23172324 (2007) Published online in Wiley InterScien... more HYDROLOGICAL PROCESSES Hydrol. Process. 21, 23172324 (2007) Published online in Wiley InterScience (www.interscience.wiley.com) DOI: 10.1002/hyp.6756 ... Temporal and spatial variations in topsoil water repellency ... JJ Keizer,1* SH Doerr,2 MC Malvar,1 AJD ...
The EROSFIRE project (POCI/AGR/60354/2004), funded by Portugal's Foundation for Science and Techn... more The EROSFIRE project (POCI/AGR/60354/2004), funded by Portugal's Foundation for Science and Technology (FCT), has as overall aim the development of a software tool that allows to assess and map, at the scale of individual hill slopes, soil erosion hazard in recently burned forest areas for different scenarios of post-fire land management. At the origin of the EROSFIRE project was the ''Soil losses after the forest fires of the summer of 2003''-map elaborated by Portugal's Water Institute (INAG) using some modified version of the Universal Soil Loss Equation (USLE), and the idea to test the applicability of erosion models with a more up-to-date scientific basis than USLE.
The aim of this study was to improve the existing knowledge of the runoff and inter-rill erosion ... more The aim of this study was to improve the existing knowledge of the runoff and inter-rill erosion response of forest stands following wildfire, focusing on commercial eucalypt plantations and employing field rainfall simulation experiments (RSE's). Repeated RSE's were carried out in two adjacent but contrasting eucalypt stands on steep hill slopes in north-central Portugal that suffered a moderate severity fire in July 2005. This was done at six occasions ranging from 3 to 24 months after the fire and using a paired-plot experimental design that comprised two pairs of RSE's at each site and occasion. Of the 46 RSE's: (i) 24 and 22 RSE's involved application rates of 45-50 and 80-85 mm h À 1 , respectively; (ii) 22 took place in a stand that had been ploughed in down slope direction several years before the wildfire and 24 in an unploughed stand.
The aim of this study is to improve our knowledge of the temporal and spatial variations of soil ... more The aim of this study is to improve our knowledge of the temporal and spatial variations of soil water repellency following wildfire, in particular for the eucalypt stands that now dominate the landscape of north-central Portugal.
The EROSFIRE project selected field rainfall simulation experiments (RSE's) as a time-and co... more The EROSFIRE project selected field rainfall simulation experiments (RSE's) as a time-and cost-effective approach to gather runoff and soil loss data under the rapidly changing conditions typical for commercial eucalypt plantations in Portugal following wildfires. These RSE ...
Post-fire erosion has been an important issue in recent years due to the increasing number of fir... more Post-fire erosion has been an important issue in recent years due to the increasing number of fires. Monitoring post-fire erosion in this study is part of the EROSFIRE project (POCI/AGR/60354/2004), funded by the Por-tuguese Foundation for Science and ...
... João Pedro Nunes, Maruxa Malvar, and Jan Jacob Keizer CESAM & Dept. ... empirical mod... more ... João Pedro Nunes, Maruxa Malvar, and Jan Jacob Keizer CESAM & Dept. ... empirical model predicting soil water repellency for recently burnt eucalypt stands in central Portugal, and its incorporation in the surface runoff component of the Morgan-Morgan-Finney (MMF) erosion ...
Since the late summer of 2005, the EROSFIRE project is investigating the hydrological and soil er... more Since the late summer of 2005, the EROSFIRE project is investigating the hydrological and soil erosion response in recently burnt eucalypt plantations. The study areas are located in the municipalities of Águeda, Albergaria-a-Velha and Sever de Vouga, at reasonably close distances from the project's home base at the University of Aveiro, which has allowed carrying out intensive field campaigns and,
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