Pedro Antonio Plaza-Álvarez

Hydraulic models require accurate topography and reliable Manning roughness coefficients to predict flow behaviour. This paper develops an integrated methodology to simultaneously generate high‐resolution topographic models and Manning roughness coefficient maps using tri‐stereoscopic images from the PeruSat‐1 satellite. The study was applied to the Huarmey River, Peru, covering 33.25 km ² . The methodology employs tri‐stereoscopic photogrammetric processing using the Semi‐Global Matching algorithm to generate topographic models with a spatial resolution of 0.70 m. Object‐based image analysis was used to identify 10 land cover classes, assigning Manning coefficients between 0.013 and 0.050 according to standard values. The results show a vertical RMSE of 0.434 m validated with 21 independent checkpoints, meeting ASPRS 2024 standards. Successful integration into the Hydrologic Engineering Centre's River Analysis System (HEC‐RAS) confirms operational functionality through simulation of a flow rate of 302.10 m ³ /s with stable convergence. The final cartographic products include eight thematic maps validating the applicability for flood risk management and urban land‐use planning studies.

Fungi are involved in several biotic processes in soil. Many studies have investigated the impacts of wildfire on fungal communities, but few have explored their diversity after post‐fire management. This study seeks to fill this gap by evaluating the species richness, diversity, and evenness of fungi, and many soil properties in a severely burned forest in Central‐Eastern Spain 10 years after installing log erosion barriers (LEBs) as a post‐fire management treatment. When compared to the unburned soils, all diversity indices of fungal communities—especially species richness and abundance, +39%,—significantly increased in burned and untreated sites. This was mainly due to the long time elapsed from wildfire and post‐fire treatment and the high cover of dead wood, which supported soil humidity for fungi development. Compared to burned areas, LEBs further increased fungal biodiversity, +43% in species richness, and +22% in abundance. This increased biodiversity was supported by a higher content of organic matter, nutrients, and some enzymes. Therefore, LEBs used in post‐fire management can be suitable for the increased development of some fungi species and their diversity in semi‐arid forests affected by severe wildfires.

Soil mulching has been studied as a postfire management action to reduce soil erosion in several forest environments. Less research exists about the effectiveness of mulching with straw and wood chips beyond the first year after a wildfire on sites with different slopes. To fill this gap, this study has measured soil erosion in three burned sites (untreated soils, and soils mulched using wheat straw or pine wood chips) throughout a 2.5‐year observation period in a forest of Castilla‐La Mancha (Central Eastern Spain). Soil condition and slope (gentle, < 32%, gentle vs. steep, > 38%, slopes) significantly influenced erosion, which, however, was of low entity due to the relatively low rainfall erosivity. Mulching was generally effective after the most intense events (maximum 30‐min rainfall intensity over 15 mm/h). On the gentle hillslopes, mulch application did not reduce postfire soil loss compared with the untreated sites. In contrast, on the steep slopes, the effectiveness of soil mulching was significant for the two most intense rainfall events (−30% of soil loss in plots treated with wheat straw compared with the burned and untreated sites). The cumulated soil loss significantly decreased on the treated sites (−40%) only when wheat straw was used. On steep slopes, the anti‐erosive effects of mulching were almost durable, since the mulch covered more than one‐third of the plot areas until the end of the monitoring period. These results help land managers adopt the most effective measures of postfire management in semi‐arid forests affected by severe wildfires.

One of the most common post‐fire management techniques is the construction of check dams in catchments. However, little research has explored how small check dams impact on bed profile, vegetation diversity and soil properties several years after their construction in Mediterranean ephemeral channels draining micro‐catchments burned by severe wildfires. To fill this gap, this study has evaluated the effects of rock check dams installed about 10 years ago in small catchments after a wildfire in Castilla La Mancha (Central Eastern Spain). The changes in channel morphology, plant diversity as well as a large dataset of soil properties have been analysed close to the check dams in comparison to burned but non‐regulated channels. Neither the channel slope nor bed sediment size significantly changed downstream and upstream of the structures in comparison to the non‐regulated channels. Thanks to the unexploited retention capacity, the studied control works are still able to store the mobilised sediments on occasion of the most intense floods. Higher species richness in both upstream and downstream sections (+64%) was detected, while the plant evenness was not altered compared to the non‐regulated channels. Regarding the soil properties, increases in organic matter (over 200%), nutrients (+72% for N and +152% for P) and some cations (+29% for Ca and +86% for Mg) were measured. Overall, the presence of the rock check dams in the burned micro‐catchments, although improving many key plant and soil characteristics, did not sharply change the hydrological, geomorphological and ecological conditions compared with those of the non‐regulated catchments.