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1.
Sci Total Environ ; 902: 166268, 2023 Dec 01.
Article in English | MEDLINE | ID: mdl-37595929

ABSTRACT

Climate change has led to altered fire patterns in the Mediterranean basin due to rising temperatures and greenhouse gas emissions, diminishing the resilience of forest ecosystems. To address this threat, forest management increasingly employs preventive measures like controlled burns, aiming to mitigate wildfire damage. However, understanding the impact of prescribed burns on vegetation remains crucial. Our study focuses on assessing the ecological effects of early-season prescribed burns on Macrochloa tenacissima communities within Pinus halepensis Mill forests on the Iberian Peninsula. These forests, with southeast-facing slopes and arid soils, heavily rely on alpha grass for post-fire recovery, acting as a shield against runoff and erosion. Yet, the presence of highly flammable resprouting species can lead to rapid combustible material accumulation. We evaluated parameters like coverage, floral diversity (α-diversity), aboveground plant biomass, photosynthetic activity, and chemical leaf properties of alpha grass, a year after a low-intensity controlled burn. Comparing burnt and unburnt areas revealed significant changes in α-diversity and ecophysiology of Macrochloa tenacissima due to early-season prescribed burns. These short-term shifts underscore the need for further exploration of underlying mechanisms. Our analysis also showed distinct shifts in alpha grass leaf chemical composition between the two plot types, potentially impacting post-fire recovery strategies. Although prescribed burning might not be optimal for reducing fire risk in resprouting species-dominated forests, it conserves native plants and enhances ecosystem diversity, providing valuable ecological benefits. In conclusion, our research deepens our understanding of early-season burning's repercussions on flammable vegetation dynamics and combustible material availability in semi-arid landscapes. It contributes to standardized management protocols, aiding effective forest service administration and wildfire risk reduction.


Subject(s)
Fires , Pinus , Wildfires , Ecosystem , Poaceae , Plants
2.
Sci Total Environ ; 855: 159044, 2023 Jan 10.
Article in English | MEDLINE | ID: mdl-36174695

ABSTRACT

Climate change worsening due to global warming and progressive abandonment in rural areas mean that wildfires are increasing in extent and severity terms, and are one of the major disturbances in the Mediterranean Basin. To mitigate these disturbances, preventive management tools need to be used. Fire employment is being implemented, known as prescribed burnings, as forestry actions to change vegetation lines both vertically and horizontally to eliminate forest fuel load continuity. This study aimed to know the ecological effects of late prescribed burning treatments under mixed trees. Prescribed burns were carried out in October 2019 in the municipality of Ayna, Albacete (SE Spain). To assess the short-term (12-month) fire impact on soil, we measured soil respiration with a CO2 flow chamber and analyzed soil physico-chemical properties. We also used minidisc infiltrometers to analyze soil repellency and soil hydraulic conductivity over a 1-year monitoring period. In addition, we evaluated the effects on tree strata by performing chemical nature analyses of fallen needles in Pinus pinaster after prescribed burning. According to our initial hypotheses, the results did not show significant changes in any parameter evaluated during the study period. However, some variables were affected in the first 3 months, needlefall and in microbiological activity, such as variations in soil physico-chemical properties, which can be due to long dry seasons combined with prescribed burning. This study attempts to observe and make known the effects that low-intensity prescribed burning has on soil and needlefall, which are relevant for updating forest management tools.


Subject(s)
Fires , Pinus , Soil/chemistry , Forests , Forestry , Trees
3.
J Environ Manage ; 316: 115212, 2022 Aug 15.
Article in English | MEDLINE | ID: mdl-35550959

ABSTRACT

Forest fires intensify sediment transport and aggravate local and off-site consequences of soil erosion. This study evaluates the influence of post-fire measures on structural and functional sediment connectivity (SC) in five fire-affected Mediterranean catchments, which include 929 sub-catchments, by using the "aggregated index of connectivity" (AIC) at two temporal scenarios: I) immediately after the fire and before implementing post-fire practices ('Pre-man'), and II) two years after the fire ('Post-man'). The latter includes all the emergency stabilization practices, that are hillslope barriers, check-dams and afforestation. The stream system was set as the target of the computation (STR), to be representative of intense rainfall-runoff events with effective sediment delivery outside the catchments. Output normalization (AICN) allows comparing the results of the five basins between them. The sedimentological analysis is based on specific sediment yield (SSY) -measured at the check-dams installed after the fire -, and this data is used for output evaluation. Stream density and slope variables were the most influential factors on AICN-STR results at the sub-catchment scale. Post-fire hillslope treatments (barriers when built in high densities and afforestation) significantly reduced AICN-STR in comparison with untreated areas in both structural and functional approaches. Despite the presence of hillslope treatments, the higher erosive rainfall conditions resulted in higher AICN-STR values in the Post-man scenario (functional approach). A positive and good correlation was found between the measured SSY and the AICN-STR changes due to the post-fire practices and vegetation recovery, showing the good correspondence of the computation results and the real sediment dynamics of the studied catchments. Overall, AICN demonstrated to be a useful and versatile tool for post-fire management, which needs further research to optimize its applicability.


Subject(s)
Fires , Rivers , Ecosystem , Forests , Humans , Soil
4.
Rev. clín. esp. (Ed. impr.) ; 222(1): 1-12, ene. 2022. tab, graf
Article in Spanish | IBECS | ID: ibc-204609

ABSTRACT

Fundamento: Identificar y validar una escala de riesgo de ingreso en las unidades de cuidados intensivos (UCI) en pacientes hospitalizados con enfermedad por coronavirus 2019 (COVID-19). Métodos: Realizamos una regla de derivación y otra de validación para ingreso en UCI, utilizando los datos de un registro nacional de cohortes de pacientes con infección confirmada por SARS-CoV-2 ingresados entre marzo y agosto del año 2020 (n = 16.298). Analizamos variables demográficas, clínicas, radiológicas y de laboratorio disponibles en el ingreso hospitalario. Evaluamos el rendimiento de la escala de riesgo mediante estimación del área bajo la curva de característica operativa del receptor (AROC). Utilizamos los coeficientes β del modelo de regresión para elaborar una puntuación (0 a 100 puntos) asociada con ingreso en UCI. Resultados: La edad media de los pacientes fue de 67 años; 57% varones. Un total de 1.420 (8,7%) pacientes ingresaron en la UCI. Las variables independientes asociadas con el ingreso en UCI fueron: edad, disnea, índice de comorbilidad de Charlson, cociente neutrófilos-linfocitos, lactato deshidrogenasa e infiltrados difusos en la radiografía de tórax. El modelo mostró un AROC de 0,780 (IC: 0,763-0,797) en la cohorte de derivación y un AROC de 0,734 (IC: 0,708-0,761) en la cohorte de validación. Una puntuación > 75 se asoció con una probabilidad de ingreso en UCI superior a un 30%, mientras que una puntuación < 50 redujo la probabilidad de ingreso en UCI al 15%. Conclusiós: Una puntuación de predicción simple proporcionó una herramienta útil para predecir la probabilidad de ingreso en la UCI con un alto grado de precisión (AU)


Background: This work aims to identify and validate a risk scale for admission to intensive care units (ICU) in hospitalized patients with coronavirus disease 2019 (COVID-19). Methods: We created a derivation rule and a validation rule for ICU admission using data from a national registry of a cohort of patients with confirmed SARS-CoV-2 infection who were admitted between March and August 2020 (n = 16,298). We analyzed the available demographic, clinical, radiological, and laboratory variables recorded at hospital admission. We evaluated the performance of the risk score by estimating the area under the receiver operating characteristic curve (AUROC). Using the β coefficients of the regression model, we developed a score (0 to 100 points) associated with ICU admission. Results: The mean age of the patients was 67 years; 57% were men. A total of 1,420 (8.7%) patients were admitted to the ICU. The variables independently associated with ICU admission were age, dyspnea, Charlson Comorbidity Index score, neutrophil-to-lymphocyte ratio, lactate dehydrogenase levels, and presence of diffuse infiltrates on a chest X-ray. The model showed an AUROC of 0.780 (CI: 0.763-0.797) in the derivation cohort and an AUROC of 0.734 (CI: 0.708-0.761) in the validation cohort. A score of greater than 75 points was associated with a more than 30% probability of ICU admission while a score of less than 50 points reduced the likelihood of ICU admission to 15%. Conclusion: A simple prediction score was a useful tool for forecasting the probability of ICU admission with a high degree of precision (AU)


Subject(s)
Humans , Intensive Care Units , Coronavirus Infections , Pneumonia, Viral , Pandemics , Hospitalization , Retrospective Studies , Risk Factors
5.
Disabil Rehabil Assist Technol ; 17(4): 480-486, 2022 05.
Article in English | MEDLINE | ID: mdl-32750254

ABSTRACT

MATERIALS AND METHODS: A qualitative approach was employed to track perspectives from a range of patients with chronic lung and/or heart diseases. COPD, IPF and MI outpatients from Denmark and Finland were invited to participate. Data were collected through focus group and semi-structured in-depth interviews. Qualitative analysis was performed using standard thematic analytical approaches. A topic guide was used to explore experiences and perceptions of the ARG telerehabilitation device among participants. RESULTS: Thirteen patients (4 MI, 2 IPF and 7 COPD), 3 women and 10 men aged 56 to 75 years (mean age 63.3 years) were allocated into one focus group (9 patients) and 4 interviews (4 patients). Twelve patients reported the added value of ARG and suggested constructive changes such as the adjustable screen/brightness, robust head fixation for exercise performance, easy to navigate interface and supported feedback based on exercise performance. CONCLUSION: Patients with chronic heart or lung diseases described the added value in an ARG telerehabilitation programme. Improvements for a future version of the ARG were suggested.IMPLICATIONS FOR REHABILITATIONPatients with chronic pulmonary and heart diseases have difficulties to change behaviour to a more active and healthy lifestyle, offers from the health sector to participate in rehabilitation programmes at the hospital are feasible and improves quality of life and exercise capacity. Not all the patients are capable of participating in such rehabilitation programmes due to frailty and long distance to the hospital. Telerehabilitation seems to be a potential treatment to cope with the needs expressed above.Patient involvement in the development of a telerehabilitation solution to empower chronic pulmonary and heart patients to train, ensures a positive contribution to the design of the expected augmented reality software and hardware envisioned solution for telerehabilitation.The development of a user-centered telerehabilitation platform responding to the preferences of patients with chronic disease will remove barriers that limit use and compliance and improve empowerment in future research projects.


Subject(s)
Augmented Reality , Heart Diseases , Pulmonary Disease, Chronic Obstructive , Telerehabilitation , Female , Humans , Male , Middle Aged , Motivation , Patient Compliance , Perception , Pulmonary Disease, Chronic Obstructive/rehabilitation , Quality of Life
6.
Rev Clin Esp (Barc) ; 222(1): 1-12, 2022 01.
Article in English | MEDLINE | ID: mdl-34561194

ABSTRACT

BACKGROUND: This work aims to identify and validate a risk scale for admission to intensive care units (ICU) in hospitalized patients with coronavirus disease 2019 (COVID-19). METHODS: We created a derivation rule and a validation rule for ICU admission using data from a national registry of a cohort of patients with confirmed SARS-CoV-2 infection who were admitted between March and August 2020 (N = 16,298). We analyzed the available demographic, clinical, radiological, and laboratory variables recorded at hospital admission. We evaluated the performance of the risk score by estimating the area under the receiver operating characteristic curve (AUROC). Using the ß coefficients of the regression model, we developed a score (0-100 points) associated with ICU admission. RESULTS: The mean age of the patients was 67 years; 57% were men. A total of 1420 (8.7%) patients were admitted to the ICU. The variables independently associated with ICU admission were age, dyspnea, Charlson Comorbidity Index score, neutrophil-to-lymphocyte ratio, lactate dehydrogenase levels, and presence of diffuse infiltrates on a chest X-ray. The model showed an AUROC of 0.780 (CI: 0.763-0.797) in the derivation cohort and an AUROC of 0.734 (CI: 0.708-0.761) in the validation cohort. A score of greater than 75 points was associated with a more than 30% probability of ICU admission while a score of less than 50 points reduced the likelihood of ICU admission to 15%. CONCLUSION: A simple prediction score was a useful tool for forecasting the probability of ICU admission with a high degree of precision.


Subject(s)
COVID-19 , Aged , Hospitalization , Humans , Intensive Care Units , Male , Retrospective Studies , Risk Factors , SARS-CoV-2
7.
Rev Clin Esp ; 222(1): 1-12, 2022 Jan.
Article in Spanish | MEDLINE | ID: mdl-34176952

ABSTRACT

BACKGROUND: This work aims to identify and validate a risk scale for admission to intensive care units (ICU) in hospitalized patients with coronavirus disease 2019 (COVID-19). METHODS: We created a derivation rule and a validation rule for ICU admission using data from a national registry of a cohort of patients with confirmed SARS-CoV-2 infection who were admitted between March and August 2020 (n = 16,298). We analyzed the available demographic, clinical, radiological, and laboratory variables recorded at hospital admission. We evaluated the performance of the risk score by estimating the area under the receiver operating characteristic curve (AUROC). Using the ß coefficients of the regression model, we developed a score (0 to 100 points) associated with ICU admission. RESULTS: The mean age of the patients was 67 years; 57% were men. A total of 1,420 (8.7%) patients were admitted to the ICU. The variables independently associated with ICU admission were age, dyspnea, Charlson Comorbidity Index score, neutrophil-to-lymphocyte ratio, lactate dehydrogenase levels, and presence of diffuse infiltrates on a chest X-ray. The model showed an AUROC of 0.780 (CI: 0.763-0.797) in the derivation cohort and an AUROC of 0.734 (CI: 0.708-0.761) in the validation cohort. A score of greater than 75 points was associated with a more than 30% probability of ICU admission while a score of less than 50 points reduced the likelihood of ICU admission to 15%. CONCLUSION: A simple prediction score was a useful tool for forecasting the probability of ICU admission with a high degree of precision.

8.
Arch Soc Esp Oftalmol (Engl Ed) ; 96(8): 422-429, 2021 Aug.
Article in English | MEDLINE | ID: mdl-34340780

ABSTRACT

INTRODUCTION: Anti-thrombotic drugs (antiplatelets and anticoagulants) are widely used for different clinical reasons. This means that there are an increasing number of patients undergoing elective ophthalmic surgery that are being treated with these drugs. A better knowledge of their implications and their peri-operative use may help to prevent surgical and secondary adverse events. There is often no firm recommendation on how to manage certain drugs in certain surgeries. OBJECTIVE: To review the recommendations in the scientific literature as regards managing anti-thrombotic agents during the peri-operative period of ophthalmic surgery. MATERIAL AND METHODS: A review was made of the relevant guidelines and studies using an antiplatelet and anticoagulant drugs approach for cataract, vitreo-retinal, glaucoma, oculoplastic, and strabismus surgeries. RESULTS: Recommendations about whether to continue or discontinue anti-thrombotic drugs in the peri-operative period of different ophthalmic surgical fields are presented. CONCLUSIONS: There are only firm recommendations of maintaining anti-thrombotic drugs as regards cataract surgery using phacoemulsification with topical anaesthesia. In other surgical fields, ophthalmologists should balance the risk of thromboembolic events and risks of haemorrhagic complications in order to carry out a proper management. A multi-disciplinary approach is recommended for complex cases. Additional studies should be performed to better characterise the peri-operative use of anti-thrombotic agents in order to prepare clinical guidelines for ophthalmic surgery.


Subject(s)
Ophthalmologic Surgical Procedures , Thromboembolism , Thrombosis , Anticoagulants/adverse effects , Elective Surgical Procedures , Humans , Ophthalmologic Surgical Procedures/adverse effects , Thromboembolism/prevention & control
9.
Arch. Soc. Esp. Oftalmol ; 96(8): 422-429, ago. 2021. tab
Article in Spanish | IBECS | ID: ibc-218015

ABSTRACT

Introducción Los fármacos anticoagulantes y antiagregantes son ampliamente utilizados con indicaciones médicas diversas. Por tanto, hay cada vez más pacientes que precisan una cirugía oftalmológica programada y se encuentran en tratamiento con esta medicación. El conocimiento de sus implicaciones y su correcto abordaje perioperatorio permite reducir complicaciones quirúrgicas y efectos adversos en los pacientes. En muchas ocasiones no hay una recomendación clara sobre cómo actuar con estas familias de fármacos en determinadas cirugías. Objetivo Realizar una revisión bibliográfica sobre el manejo perioperatorio de los antiagregantes y anticoagulantes en cirugía oftalmológica. Material y métodos Se revisan los protocolos y la literatura existente acerca del empleo de dichos fármacos en diversas cirugías oftálmicas: catarata, vítreo-retina, glaucoma, cirugía oculoplástica y orbitaria y estrabismo. Resultados Se referencian guías clínicas y estudios que recogen las recomendaciones acerca del mantenimiento o suspensión de antiagregantes y anticoagulantes en diferentes campos quirúrgicos de la oftalmología. Conclusiones En la cirugía de catarata mediante facoemulsificación con anestesia tópica existe evidencia de que el mantenimiento de la medicación antitrombótica es seguro. En el resto de las cirugías oftalmológicas se debería actuar en función del riesgo hemorrágico y trombótico que presente la cirugía y el paciente para su correcta utilización. En casos complejos, se recomienda un abordaje multidisciplinar. Serían necesarios más estudios para la confección de guías clínicas que facilitasen el manejo perioperatorio de estos fármacos en cirugía oftalmológica (AU)


Introduction Anti-thrombotic drugs (antiplatelets and anticoagulants) are widely used for different clinical reasons. This means that there are an increasing number of patients undergoing elective ophthalmic surgery that are being treated with these drugs. A better knowledge of their implications and their peri-operative use may help to prevent surgical and secondary adverse events. There is often no firm recommendation on how to manage certain drugs in certain surgeries. Objective To review the recommendations in the scientific literature as regards managing anti-thrombotic agents during the peri-operative period of ophthalmic surgery. Material and methods A review was made of the relevant guidelines and studies using an antiplatelet and anticoagulant drugs approach for cataract, vitreo-retinal, glaucoma, oculoplastic, and strabismus surgeries. Results Recommendations about whether to continue or discontinue anti-thrombotic drugs in the peri-operative period of different ophthalmic surgical fields are presented. Conclusions There are only firm recommendations of maintaining anti-thrombotic drugs as regards cataract surgery using phacoemulsification with topical anaesthesia. In other surgical fields, ophthalmologists should balance the risk of thromboembolic events and risks of haemorrhagic complications in order to carry out a proper management. A multi-disciplinary approach is recommended for complex cases. Additional studies should be performed to better characterise the peri-operative use of anti-thrombotic agents in order to prepare clinical guidelines for ophthalmic surgery (AU)


Subject(s)
Humans , Ophthalmologic Surgical Procedures/methods , Thromboembolism/prevention & control , Perioperative Care , Anticoagulants/administration & dosage , Elective Surgical Procedures
10.
Arch Soc Esp Oftalmol (Engl Ed) ; 96(1): 52-55, 2021 Jan.
Article in English, Spanish | MEDLINE | ID: mdl-32507721

ABSTRACT

The case is presented of a 3-month-old infant diagnosed with microphthalmos and orbital cysts. Magnetic Resonance Imaging revealed a bilateral microphthalmia with a moderate right cyst and a severe left cyst. Visual potential of the right eye was uncertain. Non-surgical treatment was decided. At the age of 2 years old, physical examination showed a significant decrease of the cysts and visual acuity of hand movements due to the residual vision of his right eye. Microphthalmos with orbital cyst is a rare congenital anomaly. Cysts tend to enlarge with time. At the moment, no standard protocol for the management of this pathology has been described. Unlike in our patient, visual acuity in these patients is usually of no-light perception. The observation could be an alternative in severe cases, since there is a possibility of spontaneous reduction, displacement, or regression of the cysts.

11.
J Appl Stat ; 48(13-15): 2525-2541, 2021.
Article in English | MEDLINE | ID: mdl-35707072

ABSTRACT

We propose a new technique for the study of multivariate count data. The proposed model is applied to the study of the number of individuals several fossil species found in a set of geographical observation points. First, we are proposing a multivariate model based on the Poisson distributions, which allows positive and negative correlations between the components. We are extending the log-linear Poisson model in the multivariate case through the conditional distributions. For this model, we obtain the maximum likelihood estimates and compute several goodness of fit statistics. Finally we illustrate the application of the proposed method over data sets: various simulated data sets and a count data set of various fossil species.

12.
Comput Methods Programs Biomed ; 198: 105782, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33065493

ABSTRACT

BACKGROUND AND OBJECTIVES: Deep learning techniques are the state-of-the-art approach to solve image classification problems in biomedicine; however, they require the acquisition and annotation of a considerable volume of images. In addition, using deep learning libraries and tuning the hyperparameters of the networks trained with them might be challenging for several users. These drawbacks prevent the adoption of these techniques outside the machine-learning community. In this work, we present an Automated Machine Learning (AutoML) method to deal with these problems. METHODS: Our AutoML method combines transfer learning with a new semi-supervised learning procedure to train models when few annotated images are available. In order to facilitate the dissemination of our method, we have implemented it as an open-source tool called ATLASS. Finally, we have evaluated our method with two benchmarks of biomedical image classification datasets. RESULTS: Our method has been thoroughly tested both with small datasets and partially annotated biomedical datasets; and, it outperforms, both in terms of speed and accuracy, the existing AutoML tools when working with small datasets; and, might improve the accuracy of models up to a 10% when working with partially annotated datasets. CONCLUSIONS: The work presented in this paper allows the use of deep learning techniques to solve an image classification problem with few resources. Namely, it is possible to train deep models with small, and partially annotated datasets of images. In addition, we have proven that our AutoML method outperforms other AutoML tools both in terms of accuracy and speed when working with small datasets.


Subject(s)
Machine Learning , Supervised Machine Learning
13.
J Environ Manage ; 277: 111405, 2021 Jan 01.
Article in English | MEDLINE | ID: mdl-33032003

ABSTRACT

Knowledge of forest soil ecology is necessary to assess vulnerability to disturbances, such as wildfires, and improve its microbial diversity and functional value. Soil microbiota play an important role in forest soil processes and are a key driver of postfire recovery, but they are very vulnerable to heat. According to future scenarios for climate and land-use change, fire regimes will undergo transformations in semiarid terrestrial ecosystems, mainly in the Mediterranean Basin. To develop tools for forest management in fire-prone areas, i.e., fire prevention, we assessed the impact of prescribed burnings on soil microorganisms in Mediterranean mixed pine forests. We hypothesised that low severity fire burns would not influence the functional diversity of soil microorganisms, although the burning season could influence that response due to seasonal variations in its vulnerability. We used the Biolog EcoPlate System to record soil biological indicators and assess the effect of the prescribed burning season (early or late season) on bacterial communities, including the soil-plant interphase. The soil microbiome response differed significantly according to vegetation coverage but prescribed burning season was not directly related. Burning increased the proportions of soil organic matter and soil organic carbon, and also promoted cation-exchange capacity and total phosphorus, which were higher following spring burns. Microbial richness and the Shannon-Weaver diversity index both showed a positive correlation with vegetation cover. However, microbial richness was triggered after burning uncovered patches of vegetation. We also noted differences in the usage pattern for the six substrate groups defined in our study: the use of carboxylic acids, amino acids and carbohydrates was higher in unburned plots and those subject to late burns, whereas amino acids did not predominate in early burn plots.


Subject(s)
Fires , Pinus , Carbon , Ecosystem , Forests , Seasons , Soil
14.
Sci Total Environ ; 696: 134033, 2019 Dec 15.
Article in English | MEDLINE | ID: mdl-31470330

ABSTRACT

Short-term fire-induced changes to the soil microbial community are usually closely associated to fire severity, which essentially consists in the fire-induced loss or decomposition of organic matter above ground and below ground. Many functional processes and soil properties, including plant recolonization and soil microorganism activity, depend on fire severity. Seven days after burning, we evaluated the impact of two fire severities (low and high) on basic soil properties and the microbial communities in an outdoor experimental controlled system composed of six forest soil monoliths. The magnitude of change in microbial community was far greater than the change in physical and chemical soil properties. Total N was the only selected soil property that significantly varied depending on fire severity. The severely burned soils experienced significant changes in overall microbial biomass composition and phylogenetic composition of bacterial communities in comparison with control plots. Immediately after the fire, in fact, phyla and genera such as Acidobacteria-Gp4 or Bacteroidetes-Ohtaekwangia were much more abundant in the control monoliths. On the other hand, Firmicutes or Proteobacteria (e.g. Firmicutes Paenibacillus, Proteobacteria Phenylobacterium) were relatively more abundant in the monoliths burned with high severity in comparison with the low severity burned ones. Overall, the effect of fire on soil microbial communities was greater in the high severity burned monoliths than in the low severity burned ones. We concluded that in Mediterranean forest ecosystems, fire significantly alters soil bacterial composition depending on its severity.


Subject(s)
Microbiota , Soil Microbiology , Wildfires , Biodiversity , Phylogeny
15.
J Environ Manage ; 246: 229-238, 2019 Sep 15.
Article in English | MEDLINE | ID: mdl-31176984

ABSTRACT

Postfire restoration practices encompass those which aim to reduce negative wildfire impacts and to improve burned area rehabilitation. Contour-felled log debris (CFD) and log erosion barriers (LEB) are two techniques used worldwide on hillslopes after wildfires in order to avoid soil erosion. In this context, it is essential to evaluate how these restoration techniques can affect soil properties by increasing or decreasing wildfire impacts. The effects on several physico-chemical and biological soil parameters were here investigated by comparing three differently treated post-fire zones. Three randomly 20 × 20 m distributed plots were set up five years after wildfire in the burned and contour-felled log debris areas (CFD plots), three others in the burned and log erosion barriers area (LEB plots) and three others in the burned and unmanaged plots (BNa plots). Three more plots were set up in an unburned area close to the burned area (UB plots). The results revealed that LEB and, to a lesser extent CFD, improved postfire soil quality, which a priori favoured helped the recovery of ecosystem functions. Our results also indicate greater efficacy of LEB and CFD in retaining sediments by limiting loss of nutrients, which is considered essential to recover vegetation after a wildfire. Post-fire restoration plans should consider the use of LEB and CFD when aiming to favour ecosystem recovery processes after wildfires.


Subject(s)
Fires , Wildfires , Ecosystem , Forests , Soil
16.
Sci Total Environ ; 671: 776-785, 2019 Jun 25.
Article in English | MEDLINE | ID: mdl-30943444

ABSTRACT

Mediterranean basins and their ecosystems have been traditionally affected by wildfires. After a wildfire, check-dam construction in channels is a widespread practice in semi-arid Mediterranean areas as an emergency action to avoid soil erosion. The ways that these structures affect channels' geomorphological and edaphic characteristics or vegetation dynamics, have been widely studied. In relation to vegetation however, the majority of studies have been conducted in mountain torrents. Our approach focuses on how ephemeral streams' vegetation, is affected locally by check-dam construction in the years following a wildfire. Vegetation and soil samplings were carried out in 17 check dams throughout a semiarid area in SE Spain, which was affected by a wildfire in 2012. Check-dams had a significant influence given the accretion of fine sediments in depositional wedges. This accumulation of fine sediments, organic matter and nutrients resulted in the formation of a suitable environment for ruderal plant development by creating a differentiated community upstream of dams. Check-dam construction also affected species diversity, with slightly higher values for the Shannon and Simpson indexes at those transects directly influenced by the structure.


Subject(s)
Climate , Ecosystem , Environmental Monitoring , Rivers/chemistry , Wildfires , Biodiversity , Geologic Sediments , Plant Development , Soil , Spain
17.
Comput Biol Med ; 108: 49-56, 2019 05.
Article in English | MEDLINE | ID: mdl-31003179

ABSTRACT

BACKGROUND AND OBJECTIVE: Deep learning techniques have been successfully applied to tackle several image classification problems in bioimaging. However, the models created from deep learning frameworks cannot be easily accessed from bioimaging tools such as ImageJ or Icy; this means that life scientists are not able to take advantage of the results obtained with those models from their usual tools. In this paper, we aim to facilitate the interoperability of bioimaging tools with deep learning frameworks. METHODS: In this project, called DeepClas4Bio, we have developed an extensible API that provides a common access point for classification models of several deep learning frameworks. In addition, this API might be employed to compare deep learning models, and to extend the functionality of bioimaging programs by creating plugins. RESULTS: Using the DeepClas4Bio API, we have developed a metagenerator to easily create ImageJ plugins. In addition, we have implemented a Java application that allows users to compare several deep learning models in a simple way using the DeepClas4Bio API. Moreover, we present three examples where we show how to work with different models and frameworks included in the DeepClas4Bio API using several bioimaging tools - namely, ImageJ, Icy and ImagePy. CONCLUSIONS: This project brings to the table benefits from several perspectives. Developers of deep learning models can disseminate those models using well-known tools widely employed by life-scientists. Developers of bioimaging programs can easily create plugins that use models from deep learning frameworks. Finally, users of bioimaging tools have access to powerful tools in a known environment for them.


Subject(s)
Image Processing, Computer-Assisted , Neural Networks, Computer , Programming Languages
18.
Sci Total Environ ; 674: 615-622, 2019 Jul 15.
Article in English | MEDLINE | ID: mdl-31029025

ABSTRACT

Fires are a complex phenomenon that may generate a chain of responses and processes that affect each part of the ecosystem. Thus, it is important to understand the magnitude of the impacts of fire on soil properties and the response of plants to this disturbance. For the moment, few studies have examined the effects of prescribed fire on large plots in afforested pine plantations in Mediterranean ecosystems. To fill this gap, the effects of a prescribed fire on runoff, soil erosion, and water quality for approximately one year after burning have been evaluated in pine plantations in south-eastern Spain. We constructed six erosion plots in the control area and six erosion plots in the burned area that were 4 m long and 2 m wide, immediately after the prescribed fire. Runoff, soil erosion and runoff water quality were studied after each rainy event in all plots. Our results reveal that prescribed fire did not significantly affect runoff and soil erosion when low intensity precipitations occur at pine plantations. In relation to water quality, water turbidity, salinity, pH, organic matter content and ionic substances concentrations increased immediately after prescribed burn, nevertheless these changes disappeared over time. We can conclude that prescribed fire can be a useful tool for fuel reduction in Mediterranean pine plantations without wide and long-term impacts to soil losses, or water quality.


Subject(s)
Agriculture/methods , Conservation of Natural Resources/methods , Fires , Ecosystem , Environmental Monitoring , Farms , Geological Phenomena , Mediterranean Region , Pinus , Rain , Soil , Spain , Water Quality
19.
J Environ Manage ; 235: 250-256, 2019 Apr 01.
Article in English | MEDLINE | ID: mdl-30684810

ABSTRACT

In the Mediterranean Basin, changes in climate and fire regime (increased recurrence and severity) reduce ecosystem services after wildfires by increasing soil degradation and losses in plant diversity. Our study was a biological approach to relate soil properties to vegetation recovery and burn severity. We focused our study on the natural recovery of the soil-plant interphase in Pinus halepensis Mill. forests located in the SE of Iberian Peninsula, a semiarid climate. We included some chemical properties 3 years after fire (available phosphorus (P) and soil organic carbon (Corg), among others), and biological soil indicators 3 and 5 years after fire (i.e. basal soil respiration (BSR), microbial biomass carbon (Cmic), carbon mineralization coefficient (Cmineral), metabolic quotient (qCO2) and microbial quotient (Cmic:Corg)). We analyzed the activity of three different enzymes: urease (UR), phosphatase (PHP) and ß-glucosidase (GLU). The changes in most chemical properties were ephemeral, but P and Corg showed higher values in burned areas, and the highest were found for low-moderate severity. Plant recovery was the triggering factor for the recovery of Corg and biological soil function. Burn severity and time after fire influenced Cmic and the Cmic:Corg, which were higher for moderate-high severity 3 years later, but were below the unburned values 5 years after fire. The microbial activities of GLU and UR were recovered in burned areas 5 years after fire. The PHP values lowered according to higher burn severity and time after fire. The soil ecological trends obtained by a principal component analysis revealed a relationship linking GLU, BSR and qCO2 that explained soil response to burn severity. PHP, Cmic and Cmic:Corg explained most of the variability related to time after fire. Our results provide insights into how burn severity, in Mediterranean fire-prone Aleppo pine stands, modulated the natural plant recovery linked to soil biochemical and microbiological response to fire. High burn severity limited natural vegetation recovery, and both reduced biological soil functionality. This knowledge can be implemented in post-fire planning to apply post-fire management (for mitigation and restoration) in which the "no intervention" tool should be contemplated. These findings provide information to be applied in adaptive forest management to improve the resilience of vulnerable ecosystems and to reduce burn severity in future fire events.


Subject(s)
Fires , Pinus , Wildfires , Ecosystem , Forests , Soil
20.
J Environ Manage ; 232: 1021-1027, 2019 Feb 15.
Article in English | MEDLINE | ID: mdl-33395754

ABSTRACT

Prescribed fire removes or reduces the plant material that is prone to forest fires by creating fuel discontinuity and minimising fire intensity. This forest management tool potentially impacts Mediterranean ecosystems hydrological response by influencing water infiltration into soil. As direct measurements (e.g. by infiltrometers) of unsaturated infiltration in soil subjected to prescribed fires are scarce, this study has evaluated changes in soil hydraulic conductivity (SHC) using Minidisk infiltrometer after prescribed fires in representative plots of forests in the Iberian Peninsula under Mediterranean semi-arid conditions: (i) pure forest of Black pine Arnold ssp salzmannii; (ii) mixed forest of Maritime and Black pine; (iii) mixed forest of Aleppo and Maritime pine. The results have shown that fire reduced the organic layer thickness and its organic matter content. Consequently, after the prescribed fire the water content of burned plots was always lower than in untreated soils; conversely, the reverse soil behaviour was noticed before applying fire. Compared to the untreated soils, and with very few exceptions, prescribed fire did not cause significant changes in SHC. No general patterns in the comparisons between treatments (burned/unburned soils), in time evolution after fires and in the interactions between these effects were detected. This means that the SHC of burned soils followed the temporal variations of untreated soils. The lack of significance of these differences between treatments could be due to the low-fire severity and the limited effect of temperature in the mineral layer on soil hydraulic properties. This effect was expected and agrees with other studies. Overall prescribed fires did not alter SHC in Mediterranean forest ecosystems under unsaturated conditions since fire was of low-severity.

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