Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 59
Filter
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.
Phys Rev E ; 107(4-1): 044212, 2023 Apr.
Article in English | MEDLINE | ID: mdl-37198858

ABSTRACT

Coupled nonlinear oscillators are ubiquitous in dynamical studies. A wealth of behaviors have been found mostly for globally coupled systems. From a complexity perspective, less studied have been systems with local coupling, which is the subject of this contribution. The phase approximation is used, as weak coupling is assumed. In particular, the so-called needle region, in parameter space, for Adler-type oscillators with nearest neighbors coupling is carefully characterized. The reason for this emphasis is that, in the border of this region to the surrounding chaotic one, computation enhancement at the edge of chaos has been reported. The present study shows that different behaviors within the needle region can be found and a smooth change of dynamics could be identified. Entropic measures further emphasize the region's heterogeneous nature with interesting features, as seen in the spatiotemporal diagrams. The occurrence of wave-like patterns in the spatiotemporal diagrams points to nontrivial correlations in both dimensions. The wave patterns change as the control parameters change without exiting the needle region. Spatial correlation is only achieved locally at the onset of chaos, with different clusters of oscillators behaving coherently while disordered boundaries appear between them.

3.
Rev Esp Cir Ortop Traumatol ; 67(4): T271-T278, 2023.
Article in English, Spanish | MEDLINE | ID: mdl-36863514

ABSTRACT

INTRODUCTION: Anterior glenohumeral dislocation in patients older than 60 years is related to rotator cuff lesion because of its pre-existing degenerative condition. However, in this age group, the scientific evidence fails to elucidate whether rotator cuff lesions are the cause or consequence of recurrent shoulder instability. The objective of this paper is to describe the prevalence of rotator cuff injuries in a series of consecutive shoulders in patients older than 60 years who suffered a first episode of traumatic glenohumeral dislocation, and its correlation with rotator cuff injuries in both shoulders. METHODS: Retrospectively, 35 patients over 60 years of age who had a first episode of unilateral traumatic anterior glenohumeral dislocation and who had MRI of both shoulders were studied, evaluating both shoulders with MRI to determine the structural damage correlation of the rotator cuff and long head of the biceps between them. RESULTS: When assessing the existence of partial or complete injury to the supraspinatus and infraspinatus tendons, the concordance on the affected and healthy sides, we have shown concordant results on both sides in 88.6 and 85.7%, respectively. The Kappa concordance coefficient was 0.72 for supraspinatus and infraspinatus tendons tear. Of the total of 35 cases evaluated, 8 (22.8%) presented at least some alteration in the tendon of the long head of the biceps on the affected side and only one (2.9%) on the healthy side, where the Kappa coefficient of concordance was 0.18. Of the 35 cases evaluated, 9 (25.7%) presented at least some retraction in the tendon of the subscapularis muscle on the affected side, while no participant showed signs of retraction in the tendon of this muscle on the healthy side. CONCLUSIONS: Our study has found a high correlation of the presence of a postero-superior rotator cuff injury after presenting a glenohumeral dislocation between the shoulder that has suffered the event and the presumably healthy contralateral shoulder. Nevertheless, we have not found this same correlation with subscapularis tendon injury and medial biceps dislocation.

4.
Rev Esp Cir Ortop Traumatol ; 67(4): 271-278, 2023.
Article in English, Spanish | MEDLINE | ID: mdl-36462725

ABSTRACT

INTRODUCTION: Anterior glenohumeral dislocation in patients older than 60 years is related to rotator cuff lesion because of its pre-existing degenerative condition. However, in this age group, the scientific evidence fails to elucidate whether rotator cuff lesions are the cause or consequence of recurrent shoulder instability. The objective of this paper is to describe the prevalence of rotator cuff injuries in a series of consecutive shoulders in patients older than 60 years who suffered a first episode of traumatic glenohumeral dislocation, and its correlation with rotator cuff injuries in both shoulders. METHODS: Retrospectively, 35 patients over 60 years of age who had a first episode of unilateral traumatic anterior glenohumeral dislocation and who had MRI of both shoulders were studied, evaluating both shoulders with MRI to determine the structural damage correlation of the rotator cuff and long head of the biceps between them. RESULTS: When assessing the existence of partial or complete injury to the supraspinatus and infraspinatus tendons, the concordance on the affected and healthy sides, we have shown concordant results on both sides in 88.6 and 85.7%, respectively. The Kappa concordance coefficient was 0.72 for supraspinatus and infraspinatus tendons tear. Of the total of 35 cases evaluated, 8 (22.8%) presented at least some alteration in the tendon of the long head of the biceps on the affected side and only one (2.9%) on the healthy side, where the Kappa coefficient of concordance was 0.18. Of the 35 cases evaluated, 9 (25.7%) presented at least some retraction in the tendon of the subscapularis muscle on the affected side, while no participant showed signs of retraction in the tendon of this muscle on the healthy side. CONCLUSIONS: Our study has found a high correlation of the presence of a postero-superior rotator cuff injury after presenting a glenohumeral dislocation between the shoulder that has suffered the event and the presumably healthy contralateral shoulder. Nevertheless, we have not found this same correlation with subscapularis tendon injury and medial biceps dislocation.

5.
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
6.
Med Intensiva (Engl Ed) ; 47(4): 203-211, 2023 04.
Article in English | MEDLINE | ID: mdl-36344338

ABSTRACT

OBJECTIVE: To determinate the adherence and barriers of our early mobilization protocol in patients who had received mechanical ventilation >48h in routine daily practice through clinical information system during all Intensive Care Unit (ICU) stay. DESIGN: Observational and prospective cohort study. SETTING: Polyvalent ICU over a three-year period (2017-2019). PATIENTS: Adult patients on mechanical ventilation >48h who met the inclusion criteria for the early mobilization protocol. INTERVENTIONS: None. MAIN VARIABLES OF INTEREST: Demographics, adherence to the protocol and putative hidden adherence, total number of mobilizations, barriers, artificial airway/ventilatory support at each mobilization level and adverse events. RESULTS: We analyzed 3269 stay-days from 388 patients with median age of 63 (51-72) years, median APACHE II 23 (18-29) and median ICU stay of 10.1 (6.2-16.5) days. Adherence to the protocol was 56.6% (1850 stay-days), but patients were mobilized in only 32.2% (1472) of all stay-days. The putative hidden adherence was 15.6% (509 stay-days) which would increase adherence to 72.2%. The most common reasons for not mobilizing patients were failure to meeting the criteria for clinical stability in 241 (42%) stay-days and unavailability of physiotherapists in 190 (33%) stay-days. Adverse events occurred in only 6 (0.4%) stay-days. CONCLUSIONS: Data form Clinical Information System showed although adherence was high, patients were mobilized in only one-third of all stay-days. Knowing the specific reason why patient were not mobilized in each stay-day allow to develop concrete decisions to increase the number of mobilizations.


Subject(s)
Early Ambulation , Intensive Care Units , Adult , Humans , Middle Aged , Aged , Prospective Studies , Early Ambulation/methods , Length of Stay , Information Systems , Observational Studies as Topic
7.
Acta Ortop Mex ; 36(1): 39-47, 2022.
Article in Spanish | MEDLINE | ID: mdl-36099572

ABSTRACT

Three-dimensional (3D) printing includes a group of technologies by means of which it is possible to generate three-dimensional objects from binary information. Orthopedics and traumatology are fields of medicine in which 3D planning has had the greatest impact, especially in trauma and oncological orthopedics. Applications of this technique include diagnosis, surgical planning, intraoperative guide creation, custom implants, surgical training, orthotic and prosthetic impression, and bioprinting. Advantages have been demonstrated in its use, such as greater technical precision, shorter surgical times, decreased blood loss and less exposure to X-rays. Although the process is increasingly optimized and accessible due to advances in software and automation, it is a technique that requires adequate training. The objective of this review is to offer an approach to this technology and its basic principles.


La impresión en tres dimensiones (3D) incluye un grupo de tecnologías por medio de las cuales es posible generar objetos tridimensionales a partir de información binaria. La ortopedia y traumatología es uno de los campos de la medicina en los que mayor impacto ha tenido la planificación 3D, en especial en trauma y ortopedia oncológica. Las aplicaciones de esta técnica incluyen el diagnóstico, planificación quirúrgica, creación de guías intraoperatorias, implantes personalizados, entrenamiento quirúrgico, impresión de ortesis y prótesis y la bioimpresión. Se han demostrado ventajas en su uso como la mayor precisión técnica, el acortamiento de tiempos quirúrgicos, disminución de pérdida sanguínea y menor exposición a rayos. Si bien el proceso está cada vez más optimizado y accesible por los avances en software y automatización, es una técnica que requiere un entrenamiento adecuado. El objetivo de esta revisión es ofrecer un acercamiento a esta tecnología y sus principios básicos.


Subject(s)
Orthopedic Procedures , Orthopedics , Traumatology , Humans , Printing, Three-Dimensional , Prostheses and Implants
8.
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
9.
Rev. cir. (Impr.) ; 74(1): 61-72, feb. 2022. tab, ilus
Article in Spanish | LILACS | ID: biblio-1388920

ABSTRACT

Resumen Introducción: Los aloinjerto cutáneos (AC) son excelentes sustitutos cutáneos temporales, sin embargo, la donación y procura de piel cadavérica, fuente habitual de AC, es baja. Objetivo: Evaluar la factibilidad de utilizar la piel proveniente de abdominoplastías como fuente de AC y su eficacia clínica. Materiales y Método: Entre el 17 de agosto de 2020 al 28 de febrero de 2021 se analizó una cohorte prospectiva de 14 pacientes femeninas sometidas a abdominoplastía por motivos estéticos, que aceptaron donar la piel del colgajo cutáneo abdominal redundante, la cual fue criopreservada. Se utilizaron los AC de piel total criopreservados (ACPTC) en 10 pacientes con diagnósticos de: pie diabético (4), laparostomía contenida (2) herida compleja extremidad inferior (2), sarcoma de cuero cabelludo recidivado (1) y melanoma (1). Resultados: Se obtuvieron 14 colgajos de piel total, los cuales fueron procesados obteniendo una superficie promedio de 302 cm2 y 8,3 láminas de distintos tamaños de utilidad clínica por paciente. En todos los pacientes en que se utilizó ACPTC hubo un prendimiento inicial del AC para posteriormente, en promedio 21 días, presentar una escara necrótica que al ser retirada presentaba un tejido vital adherido al receptor rico en fibroblastos, siendo algunos pacientes auto injertados y otros manejados con cicatrización por segunda intención como tratamiento definitivo. Discusión: Los ACPTC proporcionan una cobertura intermedia, pues una parte se integra en forma definitiva, actuando como un andamiaje biológico para la formación de una interfase sobre la cual se puede autoinjertar o dejar evolucionar con cicatrización por segunda intención y una parte es rechazada. Conclusión: La procura de piel de donante vivo, en pacientes sometidos a cirugías de contorno corporal es un proceso factible, fuente de ACPTC, los cuales permiten una nueva cobertura intermedia con múltiples aplicaciones clínicas.


Introduction: Skin allografts (SA) are outstanding temporary skin substitutes; however, cadaveric skin donation and procurement, a common source of SA, remains low. Aim: To evaluate the feasibility and clinical efficacy of using skin from abdominoplasties as a source of SA. Materials and Method: A prospective cohort was analyzed from August 17th, 2020 and February 28th, 2021, with 14 female patients submitted to abdominoplasty surgeries for aesthetic motives, who authorized skin donation from the redundant abdominal flap which was posteriorly cryopreserved. Cryopreserved total skin allografts (CTSA) was used in 10 patients with the following diagnoses: diabetic foot (4), contained laparostomy (2) complex wound of the lower limb (2), relapsing sarcoma of the scalp (1), and melanoma (1). Results: 14 CTSA were obtained, which were processed, obtaining an average area of 302 cm2 and 8.3 sheets of different sizes and clinical applications from each patient. In all patients who received CTSA, an initial attachment was observed, followed by the appearance of a necrotic scar in an average of21 days. The peeling of the latter revealed a vital tissue tightly adhered to the receptor and rich in fibroblasts. Some of the patients received autografts, and others were managed with secondary intention scarring as a definite treatment. Discussion: CTSA provide an intermediate coverage since one part is definitely adhered to, acting as a biologic scaffolding for the formation of an interface that can be autografted or left for a secondary intention scarring, and the host rejects the other portion. Conclusión: skin procurement from a living donor in patients submitted to body contour surgeries is a feasible process and significant source of CTSA, which permits a new intermediate coverage with multiple clinical uses.


Subject(s)
Humans , Female , Cryopreservation , Abdominoplasty/methods , Allografts/surgery , Skin , Medical Examination , Surveys and Questionnaires , Informed Consent
10.
Acta ortop. mex ; 36(1): 39-47, ene.-feb. 2022. tab, graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1447108

ABSTRACT

Resumen: La impresión en tres dimensiones (3D) incluye un grupo de tecnologías por medio de las cuales es posible generar objetos tridimensionales a partir de información binaria. La ortopedia y traumatología es uno de los campos de la medicina en los que mayor impacto ha tenido la planificación 3D, en especial en trauma y ortopedia oncológica. Las aplicaciones de esta técnica incluyen el diagnóstico, planificación quirúrgica, creación de guías intraoperatorias, implantes personalizados, entrenamiento quirúrgico, impresión de ortesis y prótesis y la bioimpresión. Se han demostrado ventajas en su uso como la mayor precisión técnica, el acortamiento de tiempos quirúrgicos, disminución de pérdida sanguínea y menor exposición a rayos. Si bien el proceso está cada vez más optimizado y accesible por los avances en software y automatización, es una técnica que requiere un entrenamiento adecuado. El objetivo de esta revisión es ofrecer un acercamiento a esta tecnología y sus principios básicos.


Abstract: Three-dimensional (3D) printing includes a group of technologies by means of which it is possible to generate three-dimensional objects from binary information. Orthopedics and traumatology are fields of medicine in which 3D planning has had the greatest impact, especially in trauma and oncological orthopedics. Applications of this technique include diagnosis, surgical planning, intraoperative guide creation, custom implants, surgical training, orthotic and prosthetic impression, and bioprinting. Advantages have been demonstrated in its use, such as greater technical precision, shorter surgical times, decreased blood loss and less exposure to X-rays. Although the process is increasingly optimized and accessible due to advances in software and automation, it is a technique that requires adequate training. The objective of this review is to offer an approach to this technology and its basic principles.

12.
Rehabilitacion (Madr) ; 56(1): 64-73, 2022.
Article in Spanish | MEDLINE | ID: mdl-33832759

ABSTRACT

The application of focused shockwaves and radial pressure waves in musculoskeletal pathology has had a great development in the last decade. Although most of the publications have highlighted their safety and efficacy, poor results and complications can occur. This review analyzes the main causes of its poor results, adverse effects, and complications, emphasizing their prevention.

13.
J Healthc Qual Res ; 36(6): 340-344, 2021.
Article in English | MEDLINE | ID: mdl-34246648

ABSTRACT

BACKGROUND: Occupational mutual insurance companies (OMICs), in collaboration with the Spanish Social Security System, provide healthcare and manage the economic benefits for the workers in Spain. They have ambulatory care centers that attend outpatient trauma pathology, although most of the studies published have focused on surgical and hospital activity. The aim of this study was to detect adverse events (AEs) in outpatient trauma care in the context of an OMIC. METHODS: A cohort study designed to identify harmful safety incidents (adverse events, AEs) in 2017 was conducted. A random sample of 313 medical records among patients who were visited more than 3 medical and nursing attendances during their outpatient process. The AEs detected were classified according to category, severity and preventability. RESULTS: We identified 48 AEs (15.3% of medical records, 95% CI 11.3-19.3), most of them procedure-related, while 27 (56.2%) were preventable and 46 mild (95.8%). CONCLUSIONS: The AEs identified are double than those found in primary care general consultations in Spain and are close to the lower range of studies on surgical AEs in traumatology and orthopedics. Preventable AEs were within expected limits. Over half of AEs are preventable, within that group, the mild AEs have an increased rate of preventability. These results highlight the relevance of research of patient safety in the outpatient care of trauma and orthopaedic procedures in an OMIC for patient safety and contribute to introduce improvements in outpatient care.


Subject(s)
Insurance , Medical Errors , Ambulatory Care , Cohort Studies , Humans , Spain
14.
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
15.
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
16.
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
17.
Chaos ; 29(4): 043105, 2019 Apr.
Article in English | MEDLINE | ID: mdl-31042953

ABSTRACT

While there has been a keen interest in studying computation at the edge of chaos for dynamical systems undergoing a phase transition, this has come under question for cellular automata. We show that for continuously deformed cellular automata, there is an enhancement of computation capabilities as the system moves towards cellular automata with chaotic spatiotemporal behavior. The computation capabilities are followed by looking into the Shannon entropy rate and the excess entropy, which allow identifying the balance between unpredictability and complexity. Enhanced computation power shows an increase of excess entropy, while the system entropy density has a sudden jump to values near one. The analysis is extended to a system of non-linear locally coupled oscillators that have been reported to exhibit spatiotemporal diagrams similar to cellular automata.

18.
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
19.
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
20.
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
SELECTION OF CITATIONS
SEARCH DETAIL