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Made available in DSpace on 2019-10-06T16:37:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-11-01 Generalitat de Catalunya Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) European Regional Development Fund Wildfires are common in wildland-urban interfaces (WUIs), where they represent a severe threat to inhabited urban settlements endangering both infrastructure and human life. Given these hazards, it is critical that forest management tools be designed to reduce the risk of wildfire at the WUI. In this regard, a management tool that is increasingly being adopted is that of prescribed fires; however, a complete understanding of their impact has yet to be gained. The aim of this study, therefore, is to analyze long-term soil properties after a prescribed fire and observed if the prescribed fire avoids vegetal fuel continuity. Our study area occupies a Mediterranean forest in the urban settlement of Picarany in the municipality of Almoster (Tarragona, Spain). The vegetation is composed primarily of Pinus halepensis Miller. and Quercus ilex L. and the soil type is classified as Xerorthents. Soil sampling was carried out in four campaigns: just before the prescribed fire (BPF), just after (APF), one year after (1YAPF) and 13 years after the prescribed fire (13YAPF). In each sampling period, 30 samples were taken (0–2.5 cm) from a 72-m2 experimental plot (4 × 18 m). The soil properties analyzed were total nitrogen (TN), soil organic matter (SOM), pH, electrical conductivity (EC) and extractable calcium (Ca), magnesium (Mg), potassium (K) and available phosphorus (P) concentrations. The carbon/nitrogen ratio was also calculated. A comparison of pre-fire values (2004) with long-term results (2017) shows increases of EC, Ca and Mg and decreases of TN and SOM. Despite these changes, the prescribed fire was found to be a good tool for managing forest areas. Indeed, the changes in soil properties did not represent a severely degradation of the soil and after 13 years there was no horizontal or vertical fuel continuity in the wildland-urban interface. Departamento de Ciencias Históricas y Geográficas Universidad de Tarapacá, 18 de Septiembre, 2222 PPGG (Programa de Pós-Graduação em Geografia) Universidade Estadual Paulista (UNESP), Campus Rio Claro, Avenida 24-A, n° 1515 - Bela Vista, Rio Claro GRAM (Grup de Recerca Ambiental Mediterrània) Department of Geography University of Barcelona, Montalegre, 6 Environmental Management Centre Mykolas Romeris University PPGG (Programa de Pós-Graduação em Geografia) Universidade Estadual Paulista (UNESP), Campus Rio Claro, Avenida 24-A, n° 1515 - Bela Vista, Rio Claro Generalitat de Catalunya: 2017SGR1344 FAPESP: BEPE 2018/09746-9

The global forest carbon (C) stock is estimated at 662 Gt of which 45% is in soil organic matter. Thus, comprehensive understanding of the effects of forest management practices on forest soil C stock and greenhouse gas (GHG) fluxes is needed for the development of effective forest-based climate change mitigation strategies. To improve this understanding, we synthesized peer-reviewed literature on forest management practices that can mitigate climate change by increasing soil C stocks and reducing GHG emissions. We further identified soil processes that affect soil GHG balance and discussed how models represent forest management effects on soil in GHG inventories and scenario analyses to address forest climate change mitigation potential. Forest management effects depend strongly on the specific practice and land type. Intensive timber harvesting with removal of harvest residues/stumps results in a reduction in soil C stock, while high stocking density and enhanced productivity by fertilization or dominance of coniferous species increase soil C stock. Nitrogen fertilization increases the soil C stock and N2O emissions while decreasing the CH4 sink. Peatland hydrology management is a major driver of the GHG emissions of the peatland forests, with lower water level corresponding to higher CO2 emissions. Furthermore, the global warming potential of all GHG emissions (CO2, CH4 and N2O) together can be ten-fold higher after clear-cutting than in peatlands with standing trees. The climate change mitigation potential of forest soils, as estimated by modelling approaches, accounts for stand biomass driven effects and climate factors that affect the decomposition rate. A future challenge is to account for the effects of soil preparation and other management that affects soil processes by changing soil temperature, soil moisture, soil nutrient balance, microbial community structure and processes, hydrology and soil oxygen concentration in the models. We recommend that soil monitoring and modelling focus on linking processes of soil C stabilization with the functioning of soil microbiota. This review has been supported by the grant Holistic management practices, modelling and monitoring for European forest soils – HoliSoils (EU Horizon 2020 Grant Agreement No 101000289) and the Academy of Finland Fellow project (330136, B. Adamczyk). In addition to the HoliSoils consortium partners, Dr. Abramoff contributed on this study and her work was supported by the United States Department of Energy, Office of Science, Office of Biological and Environmental Research. Oak Ridge National Laboratory is managed by UT-Battelle, LLC, for the United States Department of Energy under contract DE-AC05- 00OR22725.