30 results on '"Keizer, Jan J."'
Search Results
2. A new approach to pedestal differentiation for soil loss estimation—a case study from a burnt area in north-central Portugal
- Author
-
Verheijen, Frank G. A., Martins, Martinho A. S., Prats, Sergio A., and Keizer, Jan J.
- Published
- 2024
- Full Text
- View/download PDF
3. Short-term impacts of wildfires on the diversity and activity patterns of medium-sized mammals in Mediterranean coastal pine forests
- Author
-
Puga, João R.L., Abrantes, Nelson J.C., Moreira, Francisco, and Keizer, Jan J.
- Published
- 2024
- Full Text
- View/download PDF
4. On sustainable improvements of agricultural practices in the Bairrada region (Portugal)
- Author
-
Cunha, Maria C., Serpa, Dalila, Marques, João, Keizer, Jan J., and Abrantes, Nelson
- Published
- 2023
- Full Text
- View/download PDF
5. An exploratory study into ash mobilization using lysimeters
- Author
-
Godoy Leandro M., Simões Liliana B., Martins Martinho A.S., Machado Ana I., and Keizer Jan J.
- Subjects
wildfire ,ash ,runoff ,leachate ,erosion ,Hydraulic engineering ,TC1-978 - Abstract
Wildfires burn vegetation and leave the resultant organic and inorganic ash into the soil surface. Depending on the temperatures and burn durations, the quantity and type of ash can vary widely. Ash mobilization following wildfire is a topic of major concern, since it may result in contamination of surface water bodies within and downstream of the burnt areas.
- Published
- 2022
- Full Text
- View/download PDF
6. Biochar Increases Water Use Efficiency in Eucalypt Plants Under Water and Nutrient Limitation, with Trade-Offs Under Non-limiting Conditions
- Author
-
Verheijen, Frank G. A., Bastos, Ana Catarina, Vasques, Ana, Mesquita, Raquel, Keizer, Jan J., Silva, Flávio C., Jesus, Claudia, Amaral, Joana, and Pinto, Gloria
- Published
- 2022
- Full Text
- View/download PDF
7. Immediate impacts of wildfires on ground-dwelling macroinvertebrate communities under stones in Mediterranean oak forests
- Author
-
Puga, João R. L., primary, Moreira, Francisco, additional, Keizer, Jan J., additional, and Abrantes, Nelson J. C., additional
- Published
- 2024
- Full Text
- View/download PDF
8. What is the extension of bench terrace construction for forest plantations? The case of North Central Portugal
- Author
-
Martins, Martinho A. S., primary, Parente, Joana, additional, Keizer, Jan J., additional, and Vieira, Diana C. S., additional
- Published
- 2023
- Full Text
- View/download PDF
9. The effects of wildfire frequency on post-fire soil surface water dynamics
- Author
-
Universidad de Alicante. Departamento de Ecología, Universidad de Alicante. Instituto Multidisciplinar para el Estudio del Medio "Ramón Margalef", Gonzalez-Pelayo, Oscar, Prats, Sergio A., van den Elsen, Erik, Malvar, Maruxa Cortizo, Ritsema, Coen J., Bautista, Susana, Keizer, Jan J., Universidad de Alicante. Departamento de Ecología, Universidad de Alicante. Instituto Multidisciplinar para el Estudio del Medio "Ramón Margalef", Gonzalez-Pelayo, Oscar, Prats, Sergio A., van den Elsen, Erik, Malvar, Maruxa Cortizo, Ritsema, Coen J., Bautista, Susana, and Keizer, Jan J.
- Abstract
Increasing wildfire frequency in the Mediterranean Basin could affect future plant-soil–water-dynamics. The capacity of soils to retain water is a key parameter affecting plant post-fire regeneration. Yet, few research has looked at how different soil properties related to water retention is affected by increasing wildfire frequency. This study aimed at understanding the relationship between wildfire frequency, soil–water-related properties and the dynamics of surface water in soils. To this, after a 2012-summer wildfire in Portugal, three sets of three replicate maritime pine stands with contrasted wildfire frequency were selected (0 vs. 1 vs. 4 fires since 1975). At each of the nine study sites, three re-sprouter shrubs and neighbouring bare soil were chosen (54 microsites). There, soil cover, soil–water retention curves and surface (0–5 cm) soil–water-related properties (texture, bulk density, organic matter content, soil moisture, soil surface water repellency) were monitored for one year. Furthermore, records of post-fire soil moisture dynamics were analysed continuously using 72 probes installed at 2.5 and 7.5 cm depth. The hillslopes affected by 1 fire showed higher plant recovery than the 4 fires hillslopes. During the dry season, the threshold for water stress was reached 17 days sooner in the 4 fires hillslopes, and also 10 days sooner on bare microsites. Periods of plant water stress were longer and bare soil patches size bigger. The increase in wildfire frequency promoted high soil organic matter contents but less available water content, stressing the importance of soil organic matter quality characterization in water-related properties.
- Published
- 2023
10. Surface and subsurface flow in eucalyptus plantations in north-central Portugal
- Author
-
Boulet Anne-K., Prats Sergio A., Malvar Maruxa C., González-Pelayo Oscar, Coelho Celeste O.A., Ferreira Antonio J.D., and Keizer Jan J.
- Subjects
overland flow ,subsurface flow ,streamflow ,soil moisture ,eucalypt ,Hydraulic engineering ,TC1-978 - Abstract
In the Baixo Vouga region of north-central Portugal, forests occupy half of the territory, of which two thirds are Eucalypts plantations. The hydrological implications of this large-scale introduction of eucalypt are unknown and the aim of this exploratory study, realized in the Caramulo Mountains, was to describe overland flow (OLF), subsurface flow (SSF) and stream flow (Q) in a catchment dominated by Eucalyptus plantations. The main conclusions are that annual OLF rate is low, spatially heterogeneous between 0.1% and 6% and concentrated during the wet season as saturation excess, particularly as return flow. Infiltration-excess OLF due to the strong soil water repellence (SWR) is dominant during dry season, but produces residual runoff amount. SSF is the principal mechanism of runoff formation. It originates from matrix flow and pipe flow at the soil-bedrock interface, principally during the wet season. Matrix flow is correlated with soil moisture (SM) content, with a threshold of 25 %. Pipe flow starts with saturation of soil bottom but without saturation of the entire soil profile, due to a large network of macropores. Stream flow response is highly correlated with matrix flow behaviour in timing and intensity. SWR induces a very patchy moistening of the soil, concentrates the fluxes and accelerates them almost 100 times greater than normal percolation of the water in the matrix.
- Published
- 2015
- Full Text
- View/download PDF
11. Post-fire Regeneration Traits of Understorey Shrub Species Modulate Successional Responses to High Severity Fire in Mediterranean Pine Forests
- Author
-
Universidad de Alicante. Departamento de Ecología, Universidad de Alicante. Instituto Multidisciplinar para el Estudio del Medio "Ramón Margalef", Vasques, Ana, Baudena, Mara, Vallejo, V. Ramon, Kéfi, Sonia, Bautista, Susana, Santana, Víctor M., Baeza, M. Jaime, Maia, Paula, Keizer, Jan J., Rietkerk, Max, Universidad de Alicante. Departamento de Ecología, Universidad de Alicante. Instituto Multidisciplinar para el Estudio del Medio "Ramón Margalef", Vasques, Ana, Baudena, Mara, Vallejo, V. Ramon, Kéfi, Sonia, Bautista, Susana, Santana, Víctor M., Baeza, M. Jaime, Maia, Paula, Keizer, Jan J., and Rietkerk, Max
- Abstract
Recurrent fires can impede the spontaneous recruitment capacity of pine forests. Empirical studies have suggested that this can lead to a prolonged replacement of pine forest by shrubland, especially if shrub species are pyrophytic. Model-based studies, however, have suggested that post-fire succession of pine forest under current climatic conditions will eventually tend towards the dominance of oaks under high fire severity and recurrence. These previous modelling studies did not address the role of the various post-fire regeneration traits of the understory shrub species. Considering the dichotomy of obligate seeder vs. resprouter species, either obligate or facultative resprouter, we hypothesized that when the shrubs present are post-fire seeders, the oaks steadily occupy the forest, whereas resprouter shrub species might compete with oaks and delay or arrest post-fire succession. To test this hypothesis, we developed a dynamic, cellular automaton model for simulating post-fire successional transitions in pine forests, including shrubs, pines and oaks, and stochastic fires of regular frequency. Our results showed a strong tendency towards oak dominance as final model state and a very reduced role of fire recurrence in this final state, with low yearly acorn input delaying oak dominance. Most relevantly, and in line with our hypothesis, the trend towards oak dominance depended markedly on the two types of shrub species, being delayed by resprouter species, which extended the shrub-dominated succession stage for several centuries. Our simulation results supported the view that the type of understorey species should be a key consideration in post-fire restoration strategies aiming to enhance fire resilience.
- Published
- 2022
12. Changes of the aerodynamic characteristics of a flux site after an extensive windthrow
- Author
-
Oliveira, Bruna R. F., primary, Keizer, Jan J., additional, and Foken, Thomas, additional
- Published
- 2022
- Full Text
- View/download PDF
13. The short-to medium-to long-term effects of bench terrace construction for planting eucalypt trees on soil water repellency
- Author
-
Martins, Martinho A S, primary, González-Pelayo, Oscar, additional, Machado, Ana I, additional, Simões, Liliana B, additional, Ben-Hur, Meni, additional, and Keizer, Jan J, additional
- Published
- 2022
- Full Text
- View/download PDF
14. On sustainable improvements of agricultural practices in the Bairrada region (Portugal)
- Author
-
Cunha, Maria C., primary, Serpa, Dalila, additional, Marques, João, additional, Keizer, Jan J., additional, and Abrantes, Nelson, additional
- Published
- 2022
- Full Text
- View/download PDF
15. Assessing a seasonal calibration approach for a small forest catchment in a Mediterranean region North Central Portugal
- Author
-
van Schelve, Svenja, primary, Vieira, Diana C. S., additional, Keizer, Jan J., additional, Martins, Martinho António Santos, additional, and Boulet, Anne-Karine, additional
- Published
- 2021
- Full Text
- View/download PDF
16. Effect of bench terracing on ground dwelling arthropods
- Author
-
Simões, Liliana B, primary, Martins, Martinho A S, additional, Puga, João R L, additional, Keizer, Jan J, additional, and Abrantes, Nelson, additional
- Published
- 2021
- Full Text
- View/download PDF
17. The handbook for standardized field and laboratory measurements in terrestrial climate change experiments and observational studies (ClimEx)
- Author
-
Halbritter, Aud H., De Boeck, Hans J., Eycott, Amy E., Reinsch, Sabine, Robinson, David A., Vicca, Sara, Berauer, Bernd, Christiansen, Casper T., Estiarte, Marc, Grunzweig, Jose M., Gya, Ragnhild, Hansen, Karin, Jentsch, Anke, Lee, Hanna, Linder, Sune, Marshall, John, Penuelas, Josep, Schmidt, Inger Kappel, Stuart-Haentjens, Ellen, Wilfahrt, Peter, Vandvik, Vigdis, Abrantes, Nelson, Almagro, Maria, Althuizen, Inge H. J., Barrio, Isabel C., te Beest, Mariska, Beier, Claus, Beil, Ilka, Berry, Z. Carter, Birkemoe, Tone, Bjerke, Jarle W., Blonder, Benjamin, Blume-Werry, Gesche, Bohrer, Gil, Campos, Isabel, Cernusak, Lucas A., Chojnicki, Bogdan H., Cosby, Bernhard J., Dickman, Lee T., Djukic, Ika, Filella, Iolanda, Fuchslueger, Lucia, Gargallo-Garriga, Albert, Gillespie, Mark A. K., Goldsmith, Gregory R., Gough, Christopher, Halliday, Fletcher W., Hegland, Stein Joar, Hoch, Guenter, Holub, Petr, Jaroszynska, Francesca, Johnson, Daniel M., Jones, Scott B., Kardol, Paul, Keizer, Jan J., Klem, Karel, Konestabo, Heidi S., Kreyling, Juergen, Kroel-Dulay, Gyorgy, Landhausser, Simon M., Larsen, Klaus S., Leblans, Niki, Lebron, Inma, Lehmann, Marco M., Lembrechts, Jonas J., Lenz, Armando, Linstaedter, Anja, Llusia, Joan, Macias-Fauria, Marc, Malyshev, Andrey, V, Mand, Pille, Marshall, Miles, Matheny, Ashley M., McDowell, Nate, Meier, Ina C., Meinzer, Frederick C., Michaletz, Sean T., Miller, Megan L., Muffler, Lena, Oravec, Michal, Ostonen, Ivika, Porcar-Castell, Albert, Preece, Catherine, Prentice, Iain C., Radujkovic, Dajana, Ravolainen, Virve, Ribbons, Relena, Ruppert, Jan C., Sack, Lawren, Sardans, Jordi, Schindlbacher, Andreas, Scoffoni, Christine, Sigurdsson, Bjarni D., Smart, Simon, Smith, Stuart W., Soper, Fiona, Speed, James D. M., Sverdrup-Thygeson, Anne, Sydenham, Markus A. K., Taghizadeh-Toosi, Arezoo, Telford, Richard J., Tielboerger, Katja, Topper, Joachim P., Urban, Otmar, van der Ploeg, Martine, Van Langenhove, Leandro, Vecerova, Kristyna, Ven, Arne, Verbruggen, Erik, Vik, Unni, Weigel, Robert, Wohlgemuth, Thomas, Wood, Lauren K., Zinnert, Julie, Zurba, Kamal, Halbritter, Aud H., De Boeck, Hans J., Eycott, Amy E., Reinsch, Sabine, Robinson, David A., Vicca, Sara, Berauer, Bernd, Christiansen, Casper T., Estiarte, Marc, Grunzweig, Jose M., Gya, Ragnhild, Hansen, Karin, Jentsch, Anke, Lee, Hanna, Linder, Sune, Marshall, John, Penuelas, Josep, Schmidt, Inger Kappel, Stuart-Haentjens, Ellen, Wilfahrt, Peter, Vandvik, Vigdis, Abrantes, Nelson, Almagro, Maria, Althuizen, Inge H. J., Barrio, Isabel C., te Beest, Mariska, Beier, Claus, Beil, Ilka, Berry, Z. Carter, Birkemoe, Tone, Bjerke, Jarle W., Blonder, Benjamin, Blume-Werry, Gesche, Bohrer, Gil, Campos, Isabel, Cernusak, Lucas A., Chojnicki, Bogdan H., Cosby, Bernhard J., Dickman, Lee T., Djukic, Ika, Filella, Iolanda, Fuchslueger, Lucia, Gargallo-Garriga, Albert, Gillespie, Mark A. K., Goldsmith, Gregory R., Gough, Christopher, Halliday, Fletcher W., Hegland, Stein Joar, Hoch, Guenter, Holub, Petr, Jaroszynska, Francesca, Johnson, Daniel M., Jones, Scott B., Kardol, Paul, Keizer, Jan J., Klem, Karel, Konestabo, Heidi S., Kreyling, Juergen, Kroel-Dulay, Gyorgy, Landhausser, Simon M., Larsen, Klaus S., Leblans, Niki, Lebron, Inma, Lehmann, Marco M., Lembrechts, Jonas J., Lenz, Armando, Linstaedter, Anja, Llusia, Joan, Macias-Fauria, Marc, Malyshev, Andrey, V, Mand, Pille, Marshall, Miles, Matheny, Ashley M., McDowell, Nate, Meier, Ina C., Meinzer, Frederick C., Michaletz, Sean T., Miller, Megan L., Muffler, Lena, Oravec, Michal, Ostonen, Ivika, Porcar-Castell, Albert, Preece, Catherine, Prentice, Iain C., Radujkovic, Dajana, Ravolainen, Virve, Ribbons, Relena, Ruppert, Jan C., Sack, Lawren, Sardans, Jordi, Schindlbacher, Andreas, Scoffoni, Christine, Sigurdsson, Bjarni D., Smart, Simon, Smith, Stuart W., Soper, Fiona, Speed, James D. M., Sverdrup-Thygeson, Anne, Sydenham, Markus A. K., Taghizadeh-Toosi, Arezoo, Telford, Richard J., Tielboerger, Katja, Topper, Joachim P., Urban, Otmar, van der Ploeg, Martine, Van Langenhove, Leandro, Vecerova, Kristyna, Ven, Arne, Verbruggen, Erik, Vik, Unni, Weigel, Robert, Wohlgemuth, Thomas, Wood, Lauren K., Zinnert, Julie, and Zurba, Kamal
- Abstract
Climate change is a world-wide threat to biodiversity and ecosystem structure, functioning and services. To understand the underlying drivers and mechanisms, and to predict the consequences for nature and people, we urgently need better understanding of the direction and magnitude of climate change impacts across the soil-plant-atmosphere continuum. An increasing number of climate change studies are creating new opportunities for meaningful and high-quality generalizations and improved process understanding. However, significant challenges exist related to data availability and/or compatibility across studies, compromising opportunities for data re-use, synthesis and upscaling. Many of these challenges relate to a lack of an established 'best practice' for measuring key impacts and responses. This restrains our current understanding of complex processes and mechanisms in terrestrial ecosystems related to climate change. To overcome these challenges, we collected best-practice methods emerging from major ecological research networks and experiments, as synthesized by 115 experts from across a wide range of scientific disciplines. Our handbook contains guidance on the selection of response variables for different purposes, protocols for standardized measurements of 66 such response variables and advice on data management. Specifically, we recommend a minimum subset of variables that should be collected in all climate change studies to allow data re-use and synthesis, and give guidance on additional variables critical for different types of synthesis and upscaling. The goal of this community effort is to facilitate awareness of the importance and broader application of standardized methods to promote data re-use, availability, compatibility and transparency. We envision improved research practices that will increase returns on investments in individual research projects, facilitate second-order research outputs and create opportunities for collaboration across scientif
- Published
- 2020
18. Advances in Understanding and Managing Catastrophic Ecosystem Shifts in Mediterranean Ecosystems
- Author
-
Universidad de Alicante. Departamento de Ecología, CEAM (Centro de Estudios Ambientales del Mediterráneo), van den Elsen, Erik, Stringer, Lindsay C., De Ita, Cecilia, Hessel, Rudi, Kéfi, Sonia, Schneider, Florian D., Bautista, Susana, Mayor, Angeles G., Baudena, Mara, Rietkerk, Max, Valdecantos, Alejandro, Vallejo, Victoriano R., Geeson, Nichola, Brandt, C. Jane, Fleskens, Luuk, Hemerik, Lia, Panagos, Panos, Valente, Sandra, Keizer, Jan J., Schwilch, Gudrun, Riva, Matteo Jucker, Sietz, Diana, Christoforou, Michalakis, Hadjimitsis, Diofantos G., Papoutsa, Christiana, Quaranta, Giovanni, Salvia, Rosanna, Tsanis, Ioannis K., Daliakopoulos, Ioannis, Claringbould, Heleen, Ruiter, Peter C. de, Universidad de Alicante. Departamento de Ecología, CEAM (Centro de Estudios Ambientales del Mediterráneo), van den Elsen, Erik, Stringer, Lindsay C., De Ita, Cecilia, Hessel, Rudi, Kéfi, Sonia, Schneider, Florian D., Bautista, Susana, Mayor, Angeles G., Baudena, Mara, Rietkerk, Max, Valdecantos, Alejandro, Vallejo, Victoriano R., Geeson, Nichola, Brandt, C. Jane, Fleskens, Luuk, Hemerik, Lia, Panagos, Panos, Valente, Sandra, Keizer, Jan J., Schwilch, Gudrun, Riva, Matteo Jucker, Sietz, Diana, Christoforou, Michalakis, Hadjimitsis, Diofantos G., Papoutsa, Christiana, Quaranta, Giovanni, Salvia, Rosanna, Tsanis, Ioannis K., Daliakopoulos, Ioannis, Claringbould, Heleen, and Ruiter, Peter C. de
- Abstract
One of the most challenging issues in Mediterranean ecosystems to date has been to understand the emergence of discontinuous changes or catastrophic shifts. In the era of the 2030 Sustainable Development Goals, which encompass ideas around Land Degradation Neutrality, advancing this understanding has become even more critical and urgent. The aim of this paper is to synthesize insights into the drivers, processes and management of catastrophic shifts to highlight ways forward for the management of Mediterranean ecosystems. We use a multidisciplinary approach that extends beyond the typical single site, single scale, single approach studies in the current literature. We link applied and theoretical ecology at multiple scales with analyses and modeling of human–environment–climate relations and stakeholder engagement in six field sites in Mediterranean ecosystems to address three key questions: i) How do major degradation drivers affect ecosystem functioning and services in Mediterranean ecosystems? ii) What processes happen in the soil and vegetation during a catastrophic shift? iii) How can management of vulnerable ecosystems be optimized using these findings? Drawing together the findings from the use of different approaches allows us to address the whole pipeline of changes from drivers through to action. We highlight ways to assess ecosystem vulnerability that can help to prevent ecosystem shifts to undesirable states; identify cost-effective management measures that align with the vision and plans of land users; and evaluate the timing of these measures to enable optimization of their application before thresholds are reached. Such a multidisciplinary approach enables improved identification of early warning signals for discontinuous changes informing more timely and cost-effective management, allowing anticipation of, adaptation to, or even prevention of, undesirable catastrophic ecosystem shifts.
- Published
- 2020
19. Advances in Understanding and Managing Catastrophic Ecosystem Shifts in Mediterranean Ecosystems
- Author
-
van den Elsen, H.G.M., Stringer, Lindsay C., de Ita, Cecilia, Hessel, R., Kéfi, Sonia, Schneider, Florian D., Bautista, Susana, Mayor, Angeles G., Baudena, Mara, Rietkerk, Max, Valdecantos, Alejandro, Vallejo, Victoriano R., Geeson, Nichola, Brandt, Jane, Fleskens, L., Hemerik, Lia, Panagos, Panos, Valente, Sandra, Keizer, Jan J., Schwilch, Gudrun, Jucker Riva, Matteo, Sietz, D., Christoforou, Michalakis, Hadjimitsis, Diofantos G., Papoutsa, Christiana, Quaranta, Giovanni, Salvia, Rosanna, Tsanis, Ioannis K., Daliakopoulos, Ioannis N., Claringbould, Heleen, de Ruiter, P.C., van den Elsen, H.G.M., Stringer, Lindsay C., de Ita, Cecilia, Hessel, R., Kéfi, Sonia, Schneider, Florian D., Bautista, Susana, Mayor, Angeles G., Baudena, Mara, Rietkerk, Max, Valdecantos, Alejandro, Vallejo, Victoriano R., Geeson, Nichola, Brandt, Jane, Fleskens, L., Hemerik, Lia, Panagos, Panos, Valente, Sandra, Keizer, Jan J., Schwilch, Gudrun, Jucker Riva, Matteo, Sietz, D., Christoforou, Michalakis, Hadjimitsis, Diofantos G., Papoutsa, Christiana, Quaranta, Giovanni, Salvia, Rosanna, Tsanis, Ioannis K., Daliakopoulos, Ioannis N., Claringbould, Heleen, and de Ruiter, P.C.
- Abstract
One of the most challenging issues in Mediterranean ecosystems to date has been to understand the emergence of discontinuous changes or catastrophic shifts. In the era of the 2030 Sustainable Development Goals, which encompass ideas around Land Degradation Neutrality, advancing this understanding has become even more critical and urgent. The aim of this paper is to synthesize insights into the drivers, processes and management of catastrophic shifts to highlight ways forward for the management of Mediterranean ecosystems. We use a multidisciplinary approach that extends beyond the typical single site, single scale, single approach studies in the current literature. We link applied and theoretical ecology at multiple scales with analyses and modeling of human–environment–climate relations and stakeholder engagement in six field sites in Mediterranean ecosystems to address three key questions:i) How do major degradation drivers affect ecosystem functioning and services in Mediterranean ecosystems?ii) What processes happen in the soil and vegetation during a catastrophic shift?iii) How can management of vulnerable ecosystems be optimized using these findings?Drawing together the findings from the use of different approaches allows us to address the whole pipeline of changes from drivers through to action. We highlight ways to assess ecosystem vulnerability that can help to prevent ecosystem shifts to undesirable states; identify cost-effective management measures that align with the vision and plans of land users; and evaluate the timing of these measures to enable optimization of their application before thresholds are reached. Such a multidisciplinary approach enables improved identification of early warning signals for discontinuous changes informing more timely and cost-effective management, allowing anticipation of, adaptation to, or even prevention of, undesirable catastrophic ecosystem shifts.
- Published
- 2020
20. Advances in Understanding and Managing Catastrophic Ecosystem Shifts in Mediterranean Ecosystems
- Author
-
van den Elsen, Erik, primary, Stringer, Lindsay C., additional, De Ita, Cecilia, additional, Hessel, Rudi, additional, Kéfi, Sonia, additional, Schneider, Florian D., additional, Bautista, Susana, additional, Mayor, Angeles G., additional, Baudena, Mara, additional, Rietkerk, Max, additional, Valdecantos, Alejandro, additional, Vallejo, Victoriano R., additional, Geeson, Nichola, additional, Brandt, C. Jane, additional, Fleskens, Luuk, additional, Hemerik, Lia, additional, Panagos, Panos, additional, Valente, Sandra, additional, Keizer, Jan J., additional, Schwilch, Gudrun, additional, Jucker Riva, Matteo, additional, Sietz, Diana, additional, Christoforou, Michalakis, additional, Hadjimitsis, Diofantos G., additional, Papoutsa, Christiana, additional, Quaranta, Giovanni, additional, Salvia, Rosanna, additional, Tsanis, Ioannis K., additional, Daliakopoulos, Ioannis, additional, Claringbould, Heleen, additional, and de Ruiter, Peter C., additional
- Published
- 2020
- Full Text
- View/download PDF
21. Do wildfire and slope aspect affect soil water repellency in eucalypt plantations? – A two-year high resolution temporal dataset
- Author
-
Martins, Martinho A.S., primary, Verheijen, Frank G.A., additional, Malvar, Maruxa C., additional, Serpa, Dalila, additional, González-Pelayo, Oscar, additional, and Keizer, Jan J., additional
- Published
- 2020
- Full Text
- View/download PDF
22. Hydrological and Erosion Processes in Terraced Fields : Observations from a Humid Mediterranean Region in Northern Portugal
- Author
-
Nunes, João P., Bernard-Jannin, Léonard, Rodríguez Blanco, María L., Santos, Juliana M., de Oliveira Alves Coelho, Celeste, and Keizer, Jan J.
- Subjects
terrace ,águas de lima ,hydrological processes ,Mediterranean climate ,erosion - Abstract
Terraces are a common Mediterranean feature influencing soils, slopes and subsurface hydrology; however, little is known about their impact on hydrological processes, especially in humid regions. This work studied hydrological and erosion processes in the “águas de lima” terrace system common in northwestern Iberia, characterized by wet season irrigation to keep soils saturated and avoid frost on winter pastures. Soil moisture, vegetation height, runoff and sediment yield were monitored for a terraced field in northern Portugal during 19 months. Relationships between rainfall, soil, vegetation, runoff and erosion were analyzed for 49 rainfall events, and within-storm patterns of soil moisture and runoff were further evaluated for the 12 largest events. Monitoring included two wet seasons with 1264 and 951-mm rainfall. Runoff followed rainfall with 20 · 5 and 3 · 8 mm, and was mostly related with event and pre-event rainfall. Combined with hydrograph analysis, this indicated a dominance of saturation-excess runoff generation, probably related with the presence of a shallow water table caused by limited drainage and constant irrigation during winter. Rill erosion was only observed as a result of run-on from the irrigation network. Sediment yield was low, 0 · 01 and 0 · 02 Mg ha−1 in the first and second year, and related with runoff, but vegetation cover was found to limit sediment concentration. This work indicates that “águas de lima” terraces promote saturation, runoff generation and a small amount of sediment yield which does not appear relevant for soil conservation. Further work is needed to better understand and conceptualize these processes.
- Published
- 2018
23. Post‐fire soil erosion mitigation at the scale of swales using forest logging residues at a reduced application rate
- Author
-
Prats, Sergio A., primary, González‐Pelayo, Óscar, additional, Silva, Flavio C., additional, Bokhorst, Koen J., additional, Baartman, Jantiene E.M., additional, and Keizer, Jan J., additional
- Published
- 2019
- Full Text
- View/download PDF
24. How does land management contribute to the resilience of Mediterranean forests and rangelands? A participatory assessment
- Author
-
Universidad de Alicante. Departamento de Ecología, CEAM (Centro de Estudios Ambientales del Mediterraneo), Jucker Riva, Matteo, Baeza, Jaime, Bautista, Susana, Christoforou, Michalakis, Daliakopoulos, Ioannis N., Hadjimitsis, Diofantos, Keizer, Jan J., Liniger, Hanspeter, Quaranta, Giovanni, Ribeiro, Cristina, Salvia, Rosanna, Tsanis, Ioannis K., Urgeghe, Anna M., Valdecantos, Alejandro, Schwilch, Gudrun, Universidad de Alicante. Departamento de Ecología, CEAM (Centro de Estudios Ambientales del Mediterraneo), Jucker Riva, Matteo, Baeza, Jaime, Bautista, Susana, Christoforou, Michalakis, Daliakopoulos, Ioannis N., Hadjimitsis, Diofantos, Keizer, Jan J., Liniger, Hanspeter, Quaranta, Giovanni, Ribeiro, Cristina, Salvia, Rosanna, Tsanis, Ioannis K., Urgeghe, Anna M., Valdecantos, Alejandro, and Schwilch, Gudrun
- Abstract
In Mediterranean forests and rangelands, the supply of important ecosystem services can decrease or cease as a consequence of disturbances and climatic oscillations. Land managers can sometimes prevent or mitigate the negative effects of disturbances through appropriate land management choices. In this study, we assess the contribution of land management practices (LMPs) to the resilience of eight Mediterranean forests and rangelands to multiple disturbances. The study uses a transdisciplinary approach, involving scientists, land managers, and local administrators. Data about disturbances, ecosystem services, the role of LMPs, and the resistance of LMPs to disturbances are combined using a semiquantitative index and analysed to evaluate how the LMPs implemented are suited to the disturbances affecting each study site. Our results indicate that the practices analysed are particularly effective in improving resilience of ecosystems against wildfires and torrential rainfalls. However, droughts are more difficult to address, and the examined practices were heavily affected by their occurrence. Tree planting appears to be highly affected by disturbances. Practices that selectively reduce the amount of vegetation appear to be beneficial in fostering recovery of ecosystems. Our assessment also suggests that it is particularly difficult to increase resilience to droughts and fires simultaneously. Practices that aimed to mitigate the impact of land use did not always prove valuable in terms of resilience. Finally, study sites that included efforts to address disturbances in their management objectives also displayed practices making the biggest contribution to resilience.
- Published
- 2018
25. Soil Water Repellency Severity and its Spatio‐Temporal Variation in Burnt Eucalypt Plantations in North‐Central Portugal
- Author
-
Malvar, Maruxa C., primary, Prats, Sergio A., additional, Nunes, João P., additional, and Keizer, Jan J., additional
- Published
- 2015
- Full Text
- View/download PDF
26. Monitorización de la flora y vegetación de las zonas húmedas en el Baixo Vouga Lagunar (Ría de Aveiro, Portugal)
- Author
-
Almagro Bonmatí, M., Garrido Martín, B., Lopes, L., Pinho, R., and Keizer, Jan J.
- Subjects
lcsh:GE1-350 ,Parcelas permanentes ,Wetlands ,Permanent plots ,Spatio-temporal patterns ,Distribución espacio-temporal ,Zonas húmedas ,Braun-Blanquet ,Dike ,lcsh:Environmental sciences ,Dique ,TWINSPAN - Abstract
El carácter transicional de la Ría de Aveiro le confiere una riqueza florística singular, integrando comunidades vegetales típicas de las regiones Eurosiberiana y Mediterránea. La implantación del Proyecto Desenvolvimento Agrícola do Vouga (PDAV) va a provocar una modificación de las tasas de encharcamiento y una reducción gradual de la salinidad, factores ecológicos determinantes para muchas de las comunidades halófilas y helofíticas. El presente trabajo pretende contribuir a un mejor conocimiento de la tipología de la vegetación local, que sirva como base para desarrollar un programa de monitorización adecuado que detecte las alteraciones en los patrones espacio- temporales de la vegetación de los sistemas húmedos. Teniendo como objetivo seleccionar los puntos de muestreo donde instalar las parcelas permanentes de monitorización, se realizó una caracterización de la flora y la vegetación a través de trece transectos utilizando una aproximación simplificada al método de Braun- Blanquet. Una vez identificados los tipos de vegetación - en función de su composición florística, corología y ecología - fueron seleccionados al azar inventarios representativos de cada tipo, en los que han sido instaladas dichas parcelas. The transitional biogeographic character of the Ria de Aveiro lagoon area confers it a singular floristic richness, integrating plant communities typical for the Eurosiberian as well as Mediterranean Region. The implementation of the Agricultural Development Plan of the Lower Vouga area (PDAV) in the near future is expected to result in noticeable changes in the tidal submersion regime and a gradual reduction of salinity levels, which are determining ecological factors for many of the halophytic and helophytic plant communities. The present work pretends to contribute to a better knowledge of the local vegetation types and, thereby, to the implementation of an adequate monitoring programme for detecting changes in the spatio-temporal vegetation patterns of the wetlands. With the objective to select the locations for the installation of permanent quadrats, the vegetation of the wetlands was described along 13 transects using a simplified Braun-Blanquet approach. A total of 24 local vegetation types were recognised, 23 of which were selected for the current monitoring programme.
- Published
- 2006
27. Soil Water Repellency Severity and its Spatio-Temporal Variation in Burnt Eucalypt Plantations in North-Central Portugal.
- Author
-
Malvar, Maruxa C., Prats, Sergio A., Nunes, João P., and Keizer, Jan J.
- Subjects
SOIL moisture ,EUCALYPTUS ,RAINFALL ,SOIL physics ,SOIL drying - Abstract
Soil water repellency (SWR) is a dynamic soil property that influences soil hydrology. The main goal of this work was to determine in situ spatial and temporal variations in SWR in six recently burnt eucalypt stands with different pre- and post-fire management. The severity of SWR was measured in the field using the 'molarity of an ethanol droplet test' during 1-2 years, at intervals of 1-2 weeks. Measurements were taken for the ash layer, soil surface and three different soil depths (2-3, 7-8 and 14-16 cm). The volumetric soil moisture content (SMC) was measured at the three deepest layers. The results showed that ploughing operations carried out several years before the fire did not have major impacts on the severity of SWR. The ash layer was predominately wettable, whereas the other soil layers were dominated by strong to extreme severity SWR. Furthermore, and starting at a soil depth of 3 cm, the severity of repellency decreased with increasing depth. The spatial variability within a slope was significant on half of the sampling days, indicating that wettable patches were present under median severely repellent conditions, possibly increasing hydrological connectivity within the slopes. Temporal SWR patterns were inversely related to antecedent rainfall and SMC. The SWR patterns were similar between sites, as well as for the different sampling depths within each site. Major changes in the median levels of repellency were registered in periods as short as 1-2 weeks, but measured rainfall and/or soil moisture conditions were insufficient to explain these changes. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
28. Elemental Composition of Natural Nanoparticles and Fine Colloids in European Forest Stream Waters and Their Role as Phosphorus Carriers
- Author
-
Gottselig, Nina, Amelung, Wulf, Kirchner, James W., Bol, Roland, Eugster, Werner, Granger, Steven J., Hernández-Crespo, Carmen, Herrmann, Frank, Keizer, Jan J., Korkiakoski, Mika, Laudon, Hjalmar, Lehner, Irene, Löfgren, Stefan, Lohila, Annalea, Macleod, C.J.A., Mölder, Meelis, Müller, Christin, Nasta, Paolo, Nischwitz, Volker, Paul-Limoges, Eugénie, Pierret, Marie C., Pilegaard, Kim, Romano, N., Sebastià, M.-Teresa, Stähli, M., Voltz, Marc, Vereecken, Harry, Siemens, Jan, and Klumpp, Erwin
- Subjects
13. Climate action ,15. Life on land - Abstract
Global Biogeochemical Cycles, 31 (10), ISSN:0886-6236, ISSN:1944-9224
29. Advances in Understanding and Managing Catastrophic Ecosystem Shifts in Mediterranean Ecosystems
- Author
-
van den Elsen, Erik, Stringer, Lindsay C., De Ita, Cecilia, Hessel, Rudi, Kéfi, Sonia, Schneider, Florian D., Bautista, Susana, Mayor, Angeles G., Baudena, Mara, Rietkerk, Max, Valdecantos, Alejandro, Vallejo, Victoriano R., Geeson, Nichola, Brandt, C. Jane, Fleskens, Luuk, Hemerik, Lia, Panagos, Panos, Valente, Sandra, Keizer, Jan J., Schwilch, Gudrun, Jucker Riva, Matteo, Sietz, Diana, Christoforou, Michalakis, Hadjimitsis, Diofantos G., Papoutsa, Christiana, Quaranta, Giovanni, Salvia, Rosanna, Tsanis, Ioannis K., Daliakopoulos, Ioannis, Claringbould, Heleen, and de Ruiter, Peter C.
- Subjects
13. Climate action ,11. Sustainability ,15. Life on land ,12. Responsible consumption - Abstract
One of the most challenging issues in Mediterranean ecosystems to date has been to understand the emergence of discontinuous changes or catastrophic shifts. In the era of the 2030 Sustainable Development Goals, which encompass ideas around Land Degradation Neutrality, advancing this understanding has become even more critical and urgent. The aim of this paper is to synthesize insights into the drivers, processes and management of catastrophic shifts to highlight ways forward for the management of Mediterranean ecosystems. We use a multidisciplinary approach that extends beyond the typical single site, single scale, single approach studies in the current literature. We link applied and theoretical ecology at multiple scales with analyses and modeling of human–environment–climate relations and stakeholder engagement in six field sites in Mediterranean ecosystems to address three key questions: i) How do major degradation drivers affect ecosystem functioning and services in Mediterranean ecosystems? ii) What processes happen in the soil and vegetation during a catastrophic shift? iii) How can management of vulnerable ecosystems be optimized using these findings? Drawing together the findings from the use of different approaches allows us to address the whole pipeline of changes from drivers through to action. We highlight ways to assess ecosystem vulnerability that can help to prevent ecosystem shifts to undesirable states; identify cost-effective management measures that align with the vision and plans of land users; and evaluate the timing of these measures to enable optimization of their application before thresholds are reached. Such a multidisciplinary approach enables improved identification of early warning signals for discontinuous changes informing more timely and cost-effective management, allowing anticipation of, adaptation to, or even prevention of, undesirable catastrophic ecosystem shifts.
30. Post-fire CO2 efflux - the effect of soil water repellency on CO2 pulse after rewetting in a burnt pine stand in central Portugal.
- Author
-
Sanchez-Garcia, Carmen, Oliveira, Bruna, Keizer, Jan J., Doerr, Stefan H., and Urbanek, Emilia
- Published
- 2018
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.