Resumo O Brasil enfrenta altas taxas de inadimplência, devido em parte à pandemia, levando à busca de novas estratégias de cobranças de dívidas. O Machine Learning (ML), empregado com sucesso em inúmeras áreas, é aliado para elevar a eficácia dessas operações. Este artigo busca apresentar um panorama atual das pesquisas sobre aplicações de ML nas operações de cobrança de dívidas, por meio de uma Revisão Sistemática da Literatura. Foi utilizada a metodologia PICO, identificando inicialmente 41 documentos, dos quais 11 passaram por revisão sistemática. Os resultados mostraram quatro objetivos buscados pelos estudos: previsão de inadimplência, personalização das estratégias de cobrança, otimização das ações de recuperação de dívidas e previsão de recuperação de crédito. E os principais algoritmos utilizados foram Decision Tree, Logistic Regression, Random Forest, Naive Bayes, Artificial Neural Network e Deep Learning. Os resultados revelaram que ML é ainda pouco explorado nessa área, oferecendo potencial para avanços substanciais das pesquisas.

Abstract Brazil is facing high default rates, due in part to the pandemic, leading to the search for new debt collection strategies. Machine Learning (ML), successfully used in numerous areas, is an ally to increase the effectiveness of these operations. This article seeks to present a current overview of research on ML applications in debt collection operations, through a Systematic Literature Review. The PICO methodology was used, initially identifying 41 documents, of which 11 underwent systematic review. The results showed four objectives pursued by the studies: default prediction, personalization of collection strategies, optimization of debt recovery actions and credit recovery prediction. And the main algorithms used were Decision Tree, Logistic Regression, Random Forest, Naive Bayes, Artificial Neural Network and Deep Learning. The results revealed that ML is still little explored in this area, offering potential for substantial research advances.

Abstract In this article I present neo-extractivist forms of authoritarianism in the region of Carajás (southeast Pará, Brazil), which depend on extensive corporate influence on multiple scales of state governance and on multiple state powers. Based on secondary data and qualitative research carried out in Canaã dos Carajás, I discuss Vale’s operations in the municipality after the implementation of the S11D mining project. I present these contemporary forms of neo-extractivist authoritarianism in three distinct geographies: city, countryside and forest. The first is based on the production of urban space using mining royalties’ resources and the so-called “corporate social responsibility policies”; the second refers to the dispossession mechanisms of landless encampments and villages in the rural area of the municipality; and the third refers to the operationalization of the forest through conversational units and environmental legislation. neoextractivist neo extractivist southeast Pará Brazil, Brazil , Brazil) powers Vales Vale s SD S D project geographies city royalties socalled so called policies policies” legislation

Resumo Neste artigo, apresento formas neoextrativistas de autoritarismo na região de Carajás, no sudeste paraense, que dependem de uma extensa influência corporativa nas múltiplas escalas de governança estatal e nos múltiplos poderes do Estado. A partir de dados secundários e de pesquisa qualitativa realizada em Canaã dos Carajás, discuto a atuação da Vale no município após a instalação do Projeto Ferro Carajás S11D. Apresento essas formas contemporâneas de autoritarismo neoextrativista em três geografias distintas: cidade, campo e floresta. A primeira é baseada na produção do espaço urbano a partir dos recursos da Compensação Financeira pela Exploração de Recursos Minerais (CFEM) e das chamadas políticas de responsabilidade social corporativa; a segunda se refere aos mecanismos de despossessão de vilas e acampamentos sem-terra na zona rural do município; e a terceira trata da operacionalização da floresta através de unidades de conservação e da legislação ambiental. artigo paraense Estado S11D SD S D distintas cidade CFEM (CFEM semterra sem terra ambiental

High quality road infrastructure is essential to support economic growth for any region. For South Africa's landlocked economic hub 79% of goods are transported using roads infrastructure. Protection of the road infrastructure is implemented by means of overload control monitoring at traffic control centres (TCCs) on freight corridors. Statistics collected from TCC operations indicate that 75% to 85% of statically weighed vehicles are legally loaded, with the implication that unnecessary time was wasted for these vehicles. This paper therefore proposes an algorithm, called the intelligent weigh-in-motion (IWIM) algorithm, with the purpose to decrease static weighing of vehicles by implementing data sharing between TCCs on the freight corridor, combined with intelligent interpretation of this data. The selected algorithm was chosen after testing multiple artificial intelligence (AI) models (logistic regression, random forest tree, and artificial neural network) to achieve the best performance to decrease static weighing of vehicles while not increasing the number of overloaded vehicles allowed to proceed on the corridor. The best performing model to differentiate between overloaded and legal vehicles, random forest tree, achieved an average improvement of 65,83% in terms of vehicles to be statically weighed when compared to the current rule-based system employed at TCCs. CATEGORIES: · Applied computing ~ Transportation

The accurate estimation of peak particle velocity (PPV) is crucial during the design of bench blasting operations in open pit mines, since the vibrations caused by blasting can significantly affect the integrity of nearby buildings and other structures. Conventional models used to predict blast-induced vibrations are not capable of capturing nonlinear relationships between the different blasting-related parameters. Soft computing techniques, i.e., techniques that are founded on the principles of artificial intelligence, effectively model these complexities. In this paper, we use the random forest (RF) algorithm to develop a model to predict blast-induced ground vibrations from bench blasting using 48 data records. The model was trained and tested using WEKA data-mining software. To build this model, a feature selection process using several combinations of Attribute Evaluators and Search Methods under the WEKA Select Attributes tab was performed. The correlation coefficient of the actual data and RF model-predicted data was 0.95, and the weighted average of the relative absolute error (RAE) was 10.9%. The RF model performance was also compared to the equivalent-path-based (EPB) equation on the testing data-set, and it was seen that the RF model can effectively be used to predict PPV. The study also demonstrates that the EPB equation is a suitable empirical method for predicting PPV.

ABSTRACT Large-scale mining operations, such as those associated with iron extraction, disturb soils and vegetation and create the need for effective rehabilitation practices. The Iron Quadrangle region of southeastern Brazil is one of the world’s biodiversity hotspots; however, iron mining activities threaten many natural and seminatural ecosystem types in which many rare/protected species occur. The Iron Quadrangle has four main ecosystem types: Atlantic Forest (AF), ferruginous rupestrian grassland with dense vegetation (FRG-D); ferruginous rupestrian grassland with sparse vegetation (FRG-S); and quartzite rupestrian grassland (QRG). To support rehabilitation and monitoring plans, we evaluated reference areas and identified soil and vegetative attributes that best differentiated between these four ecosystems. We measured thirty-four physical, chemical, and biological soil properties and two vegetation parameters and, using a multivariate analysis, detected: 1) correlations between properties and 2) differences between areas. We identified twelve properties that best differentiated the areas (in order from most to least relevant): nickel content; exchangeable aluminum; clay content; above-ground vegetation volume; aluminum saturation; particle density; bulk density; arsenic content; zinc content; lead content, fine sand plus silt content; and fine sand content. Soil physicochemical properties proved to be more sensitive to differences in ecosystem type, and in particular, parameters related to fertility and the presence of metals and semi-metals differentiated the AF from the FRG-D and FRG-S. Soil physical properties, including fine sand and silt content, were most important for differentiating QRG from the other ecosystems, possibly resulting from the exposure of quartzite material to erosive processes. This study demonstrates the importance of identifying appropriate reference areas for post-mining reclamation. Largescale Large scale operations extraction practices worlds world s hotspots however rareprotected rare protected occur AF, , (AF) FRGD FRG D (FRG-D) FRGS S (FRG-S) QRG. . (QRG) plans ecosystems thirtyfour thirty chemical analysis detected 1 2 relevant relevant) content aboveground above ground volume saturation density type particular semimetals semi FRGS. S. FRG-S processes postmining post reclamation (AF (FRG-D (FRG-S (QRG

Abstract In this paper, we present an attention classification method using Machine-Learning Algorithms. The EEG signals were recorded from ten engineering students with an EPOC+BCI using the electrodes F3, F4, P7, and P8 while solving some mathematical operations. The recording time for these activities is around 20 minutes. Next, a similar time EEG register is obtained while doing non-academic activities, such as chattering with the staff, checking cell phones, or playing a video game. With these EEG registers, we obtained a set of features to train and evaluate attention using Machine Learning algorithms. This research shows how engineering students interact with math topics in solving mental operations and complex reasoning by increasing brain domain and knowledge for mathematical reasoningrelated processes, such as sustained and shifting attention and logical constructions for object interaction during operations resolution. The Random Forest algorithm (RF) obtained the highest accuracy with 0.7392, an F1 Score of 0.7430, and the highest Specificity/Accuracy with 0.7261.

Resumen Se presenta un método de clasificación de la atención utilizando algoritmos de aprendizaje automático. Con las señales EEG de diez estudiantes de ingeniería adquiridas utilizando los electrodos F3, F4, P7 y P8 de una BCI EPOC+ mientras resuelven productos escalares, multiplicaciones algebraicas simples, simplificaciones e integrales por aproximadamente 20 minutos. Posteriormente, se obtiene un registro EEG de tiempo similar mientras se realizan actividades no académicas, como charlar con el personal, consultar el móvil o jugar a un videojuego. Se obtienen algunas características/parámetros, se entrenan y evalúan varios algoritmos de aprendizaje automático para la clasificación de la atención. Los resultados de esta investigación pueden mejorar la forma en que los estudiantes de ingeniería interactúan con los temas matemáticos en la resolución de operaciones mentales y razonamientos complejos, aumentando el dominio y el conocimiento cerebral para los procesos relacionados con el razonamiento matemático, como la atención sostenida y cambiante y las construcciones lógicas para la interacción con objetos durante la resolución de operaciones. El clasificador Random Forest obtuvo la mayor precisión con 0.7392, una puntuación F1 de 0.7430 y la mayor especificidad/precisión con 0.7261.

Resumen El conocimiento detallado de la estructura de las plantaciones de teca es necesario para los planes de gestión sostenible. La integración de variables de teledetección con la modelización geoestadística en plantaciones de teca ha sido poco estudiada y, por tanto, el objetivo consistía en modelizar la distribución espacial de las variables del rodal de teca, incorporando covariables. El estudio se realizó en plantaciones de teca de 19 años en Brasil con 213 hectáreas en el espacio inicial de 3 m x 3 m. Se asignaron parcelas georreferenciadas de 900 m² y se obtuvieron las variables forestales después del clareo. Los índices de vegetación se calcularon a partir de operaciones aritméticas ejecutadas entre las bandas de imágenes Landsat. La interpolación de las variables forestales se procedió por el método geoestadístico univariante de kriging ordinario, así como por el método multivariante de kriging con deriva externa, considerando las variables de teledetección como covariables. El análisis estadístico de las variables de teledetección muestra una discreta correlación lineal con las variables de la teca, lo que tiende a hacer inviable su uso como covariables en la modelización geoestadística. Sin embargo, el kriging con deriva externa predice los patrones espaciales de las variables forestales con mayor detalle, lo que da como resultado a posibles errores de suavización menores que los obtenidos por el kriging ordinario, y proporciona recomendaciones más precisas para la gestión localizada en plantaciones de teca. La integración de variables de teledetección en el inventario forestal mediante geoestadística es ventajosa para cartografiar la distribución espacial de las variables de los rodales de teca.

Abstract Detailed knowledge of teak stand structure is necessary for sustainable management plans. The integration of remote sensing variables with geostatistical modeling in teak forest stands has not been sufficiently studied and, therefore, the aim was to model the spatial distribution of teak stand variables, adding covariables. The study was carried out on 19-year-old teak stand in Brazil with 213 hectares in the initial spatial of 3 m x 3 m. Geo-referenced plots of 900 m² were allocated, and forest variables were obtained after thinning. Vegetation indices were calculated from arithmetic operations conducted between the Landsat image bands. The interpolation of forest variables was performed by the geostatistical univariate method of ordinary kriging, as well as by the multivariate method of kriging with external drift, considering the remote sensing variables as covariables. Statistical analysis of remote sensing variables shows a weak linear correlation with teak variables, which tends to make them unviable to use as covariables in geostatistical modeling. However, kriging with external drift predicts spatial patterns of forest variables with greater detail, which results in lower possible smoothing errors than those obtained by ordinary kriging and provides more accurate recommendations for localized management in teak stand. The integration of remote sensing variables in forest inventory through geostatistics is advantageous for mapping the spatial distribution of teak stand variables.

Abstract In this paper we analyze some of the artistic work produced and exhibited at two public events that aimed to remember the forest fire of March 9, 2021 in the wildland-urban interface of northwestern Chubut, in Argentinian Patagonia. It particularly affected four neighborhoods settled on provincial state lands, which is why their inhabitants were the recipients of stigmatizing speeches that placed them either as “dangerous” or as needing to be assisted by the state. Our hypothesis is that just as the fire managed to make these people visible as vulnerable neighbors, the security operations months after the fire ended up breaking down the stigmatizing frames of visibility. Based on ethnographic work in the area and in-depth interviews with artists and organizers, we analyze how the artistic works managed to crack these visibility frames, showing political subjects with agency.

Resumo Neste artigo analisamos algumas obras artísticas exibidas e produzidas no âmbito de dois eventos públicos que visam lembrar o incêndio de interface urbano-florestal do 9 de março de 2021, no noroeste de Chubut, Patagônia Argentina. Esse acontecimiento atingiu particularmente quatro bairros assentados em terras fiscais provinciais, razão pela qual seus habitantes foram destino de discursos estigmatizantes que os colocavam como “perigosos” ou como necessitados da assistência do Estado. Nossa hipótese é que assim como o incêndio conseguiu tornar essas pessoas visíveis como vizinhas e vulneráveis, as operações de segurança, meses após o incêndio, acabaram rompendo os quadros de visibilidade estigmatizante. Com base em trabalhos etnográficos na área e entrevistas em profundidade com artistas e organizadores, analisaremos como as obras artísticas conseguiram romper aqueles marcos de visibilidade, mostrando sujeitos políticos com capacidade de agência.

Resumen En este artículo analizamos algunas obras artísticas exhibidas y producidas en el marco de dos eventos públicos que tuvieron como objetivo recordar el incendio de interfase urbano-forestal del 9 de marzo de 2021 en el noroeste del Chubut, Patagonia argentina. Este afectó particularmente a cuatro barrios asentados sobre tierras fiscales provinciales, motivo por el cual sus habitantes eran destinatarios de discursos estigmatizantes que los ubicaban, o bien como “peligrosos” o bien como necesitados a ser asistidos por el Estado. Nuestra hipótesis es que, así como el incendio logró visibilizar a esas personas como vecinos y vulnerables, los operativos de seguridad meses después del incendio terminaron por resquebrajar los marcos de visibilidad estigmatizantes. A partir de trabajo etnográfico en la zona y de entrevistas en profundidad a artistas y organizadores, analizamos de qué forma las obras artísticas lograron interpelar dichos marcos de visibilidad, y mostrar sujetos políticos agenciados.

Resumo O advento das concessões florestais na Amazônia Brasileira gerou expectativa de aumento de madeira legal no mercado e concomitante conservação das florestas públicas. Contudo, ainda não ganharam a escala necessária. O objetivo desse artigo foi analisar a experiência do Brasil com concessões florestais para empresas privadas desde a sanção da Lei de Gestão de Florestas Públicas (LGFP), lei 11.284/2006, sob a perspectiva dos arranjos institucionais locais. Foi analisada a documentação relacionada à implementação da LGFP combinada com as informações obtidas por meio da observação direta dos acontecimentos e entrevistas no campo. Observou-se que o desafio da garantia de direitos às populações locais gerou insegurança jurídica aos atores envolvidos comprometendo a continuidade do manejo das florestas já concedidas e novos processos de concessão. Estabelecer arranjos institucionais mais favoráveis será determinante para que a política pública contribua à mudança do setor florestal e seus estigmas.

Abstract The advent of forest concessions in the Brazilian Amazon generated the expectation of an increase in the supply of legal timber and concomitant conservation of public forests not yet reached. The aim of this article was to analyze Brazil’s experience with forest concessions for private companies since the approval of the Public Forest Management Act (LGFP), Act 11.284/2006, from the perspective of local institutional arrangements. We analyzed documentation related to the implementation of the LGFP combined with information obtained through direct observation and interviews in the field. It was observed that the challenge of guaranteeing rights to local populations has created legal uncertainty for the actors involved. This compromised the continuity of forest management operations already granted and the advancement of new concession processes. Establishing more favorable institutional arrangements will be key for the sustainable management of legal timber to contribute to changing the sector and its stigmas.

Resumen Las concesiones forestales a la Amazonia brasileña generó expectativas en el aumento de la disponibilidad de madera legal en el mercado y conservación de los bosques públicos. El objetivo de este artículo es analizar la experiencia de Brasil respecto de las concesiones forestales con la promulgación de la Ley de Gestión de Bosques Públicos (LGFP), Ley 11.284/2006, desde la perspectiva de las instituciones locales. Fue analizada la documentación relativa a la implementación de la LGFP combinada con información obtenida mediante la observación directa y entrevistas. Se observó que el desafío de garantizar los derechos de las poblaciones locales generó inseguridad jurídica para los actores implicados, comprometiendo la continuidad de la gestión de los bosques ya concesionados y nuevos casos. El establecimiento de acuerdos institucionales más favorables será determinante para que el manejo sostenible de la madera contribuya a cambiar el sector y sus estigmas.

Resumo A pulverização de herbicidas sobre a rebrota do eucalipto é uma prática comum no setor florestal. Entretanto, observa-se a necessidade de várias operações em uma mesma área para controle das brotações. Objetivou-se avaliar a eficiência dos herbicidas glyphosate e imazapyr, aplicados no fuste principal antes do corte raso das árvores, no controle de brotações de eucalipto. Foram implantados sete tratamentos representados por doses de 3,0; 4,0 e 5,0 mL/fuste de glyphosate (Gli-Up® 360 g i.a L-1) e das doses de 0,3; 0,5 e 0,7 mL/fuste de imazapyr (Chopper Florestal® 250 g i.a. L-1), além de um tratamento-testemunha. A aplicação dos herbicidas foi realizada em inserções feitas nos fustes das árvores. Aos 30 dias após aplicação dos herbicidas, realizou-se o corte das árvores. Aos 150 dias após o corte das árvores, foram realizadas avaliações do número de brotações por cepa, número de cepas com presença de brotações, altura e a eficiência de controle das brotações. A aplicação de glyphosate promoveu redução do vigor das brotações. Porém, observou-se emissão de brotações em pelo menos 80% das cepas avaliadas. A aplicação da dose de 3 mL de glyphosate promoveu porcentagens de 80% de eficiência de controle. Contudo, observou-se que operações de controle adicionais seriam necessárias. A aplicação de imazapyr mostrou-se ineficiente com controle inferior a 25%. Portanto, conclui-se que a aplicação de glyphosate no fuste da árvore em pré-corte reduz o vigor de brotações de eucalipto. Adicionalmente, a aplicação de imazapyr, nas doses e forma de aplicação testadas, não é recomendada para controle de brotações de eucalipto.

Abstract Herbicide spraying on eucalyptus regrowth prior to planting reform is a common practice in the forest sector. However, several operations are needed in the same area for an effective sprout control. The objective of this work was to evaluate the efficiency of the herbicides glyphosate and imazapyr, applied to the main stem before the harvesting of the tree to eucalyptus sprouts control. There were set up 7 treatments, with application of doses of 3.0; 4.0; and 5.0 mL/stem of glyphosate (Gli-Up® 360g i.a L-1) and doses of 0.3; 0.5; and 0.7 mL/stem of imazapyr (Chopper Florestal® 250g i.a. L-1), in addition to a control treatment. The herbicide spraying consisted of the directed spraying of the herbicides on incisions carried out on the stem of the trees. The harvest of the trees was carried out 30 days after the herbicide spraying. Assessments about the number of sprouts per stump were carried out, the number of stump with presence of coppice, height and control efficiency of the coppice 150 days after harvesting. The glyphosate spraying promoted reduction of the sprout development and vigor. However, even with this reduction, it was observed presence of sprouts in at least 80% of the assessed stumps. The spraying of the dose of 3 mL of glyphosate promoted values next to 80% of control efficiency. Nevertheless, it was observed that new control operations would be necessary. The spraying of imazapyr was inefficient with control efficiency values less than 25%. In conclusion, the application of glyphosate to the main stem before the harvesting of the tree presents reduction in the eucalyptus sprout development. Additionally, the application of imazapyr, in the doses and form application tested, is not recommended to eucalyptus sprout control.

Resumo Apresenta-se aqui um estudo sobre a relação entre as ocorrências de incêndios em vegetação e a climatologia das chuvas no Ceará. Foram usados registros das ocorrências desses eventos da Coordenadoria Integrada de Operações de Segurança (CIOPS) e os registros climatológicos da Fundação Cearense de Meteorologia e Recursos Hídricos (FUNCEME). Os resultados mostraram que existe uma relação entre a ocorrência de incêndios florestais, associados a prática de atear fogo na vegetação de forma não controlada, e as condições meteorológicas, ambientais e culturais das comunidades cearenses e que o período de estiagem (seco) é o período de maior ocorrência desses registros na região.

Abstract A study is presented here about the relationship between the occurrence of fires in vegetation and the climatology of the rains in Ceará. Records of the occurrences of these events from the Integrated Coordination of Security Operations (CIOPS) and the climatological records of the Cearense Meteorology and Water Resources Foundation (FUNCEME). The results showed that there is a relationship between the occurrence of forest fires, associated with the practice of setting fire to vegetation in an uncontrolled way, and the meteorological, environmental and cultural conditions of the communities of Ceará and that the dry season (dry season) is the period occurrence of these records in the region.

Resumen Tradicionalmente la extracción forestal de leña en el Chaco Semiárido, es ejecutada de manera precaria con implementos de escaso desarrollo tecnológico y exigua ergonomía. El empleo de máquinas agrícolas durante el aprovechamiento forestal, ocasiona un alto impacto ambiental sobre la vegetación remanente. Con la intención de minimizar los daños sobre los árboles en pie, se plantea la necesidad de diseñar nuevas alternativas mecanizadas. El objetivo de este estudio, es analizar el rendimiento y desempeño de un tractor de pequeño porte adaptado para operaciones forestales durante el transporte primario incorporando un trineo forestal. El trabajo tuvo lugar en un bosque bajo manejo de sistema silvopastoril, localizado en la región del Chaco Semiárido de Argentina, departamento Silípica, provincia de Santiago del Estero. Se registraron tiempos operativos de noventa ciclos de trabajo, rendimientos y distancias durante el aprovechamiento forestal. El material leñoso obtenido se cubicó de forma directa en las playas de acopio. Los resultados obtenidos del análisis, muestran que durante el ciclo de extracción la actividad que mayor tiempo insume es la “Carga” (0:03’:19”), seguido de la “Descarga” (0:02’:21”) y tanto el “Transporte vacío” como el “Transporte cargado” (0:01’:29”0) se mantienen similares, sumando un tiempo promedio por ciclo de trabajo de 0:08’:39”. La distancia total y media recorrida por ciclo de trabajo neto fue de 325,6 m y 162,8 m; en donde la velocidad media de traslado obtenida fue de 7,5 km/h. El rendimiento promedio de extracción de madera en forma de leña por ciclo de trabajo neto, fue de 1,02 metros cúbicos estéreos/viaje, lo que representa aproximadamente 650 kg/viaje. En virtud a las características y capacidades del equipo utilizado, el desempeño del equipo se encuentra dentro de un rango razonable, con amplias posibilidades de mejoras.

Abstract Traditionally, the forest extraction of firewood in the Semi-arid Chaco is carried out in precariously with implements of little technological development and meager ergonomics. The use of agricultural machines during forest harvesting causes high environmental impact on the remaining vegetation. Aiming at minimizing the damage to standing trees, the need to design new mechanized alternatives arises. The objective of this study is to analyze the yield and performance of a small tractor adapted for forestry operations during primary transport by incorporating a forest sled. The work was located in a forest managed by the silvopastoral system in the Semi-arid Chaco region of Argentina, Silipica Department, Province of Santiago del Estero. Ninety working-cycle operating systems, yields and distances were recorded during forest harvesting. The woody material obtained was directly cubed on the store yards. The results show that in the extraction cycle the longest activity is “Loading” (0:03': 19”), followed by “Downloading” (0:02':21”) while both “Empty Transport” and “Loaded Transport” (0:01':29 ”0) remain similar which adds an average time of 0: 08': 39” per duty cycle. The total and average distance covered was of 325.6 m and 162.8 m per net working cycle, where the mean transfer speed obtained was of 7.5 km / h. The average yield of wood extraction as firewood per net working cycle was of 1.02 stereo cubic meters / trip, which represents approximately 650 kg / trip. According to the characteristics and capabilities of the equipment used, its performance lays within a reasonable range, with ample room for improvement.

SUMMARY: Fingerprinting techniques were incorporated into a paired catchment investigation in southern Chile to quantify the contribution of three fine sediment sources (catchment surfaces, forest roads and stream channels) to catchment suspended sediment yields during forest harvesting and replanting operations. Optimum composite fingerprints for use in sediment source discrimination and apportionment comprised 137Cs and 210Pbex for the control catchment (LUC) throughout the study and for the treatment catchment (LUT) during the pre-harvest period, and 137Cs and soil organic matter during harvest and post-harvest periods for LUT. Prior to harvesting, the dominant sediment source to the sediment load in both catchments was the stream channel and remained relatively constant throughout the study for LUC. For the entire study period the total suspended sediment yield from LUT (3,160 kg ha-1) approximately doubled that from LUC (1,650 kg ha-1). Most of this difference is accounted for by the increase in sediment output during the rainy months following clearcutting. The disturbance associated with forest operations in LUT caused the contributions to the load from the catchment slopes and forest roads to increase markedly (total contributions 835 and 795 kg ha-1, respectively). However, the total contribution from the stream channel for LUT during the study period (1,530 kg ha-1) remained similar to that from LUC. The results of the investigation demonstrated that any attempt to reduce sediment loading from forest harvesting would require adopting best management practices to reduce sediment mobilization from catchment surfaces and forest roads.

RESUMEN: Técnicas de trazadores fueron incorporadas a una investigación de cuencas pareadas en el sur de Chile para cuantificar la contribución de tres fuentes de sedimentos finos (superficie de las cuencas, caminos forestales y cauces) a la carga total de sedimentos en suspensión durante las operaciones de cosecha y reforestación. La composición óptima de trazadores para discriminar y calcular la participación de cada fuente de sedimentos comprendió 137Cs y 210Pbex para la cuenca control (LUC) durante todo el estudio y para la cuenca de tratamiento (LUT) durante el período previo a la cosecha, y 137Cs y la materia orgánica del suelo durante los períodos de cosecha y post-cosecha para LUT. Antes de la cosecha, la fuente dominante de sedimentos a la carga total de sedimentos en ambas cuencas fue la red de drenaje, y permaneció relativamente constante a lo largo del estudio para LUC. Durante el periodo estudiado, la carga total de sedimentos desde LUT (3.160 kg ha-1) fue aproximadamente el doble que desde LUC (1.650 kg ha-1). Gran parte de esta diferencia se explica por el aumento de la carga de sedimentos durante los meses lluviosos luego de la cosecha. La alteración por las operaciones forestales en LUT generó que las contribuciones desde las laderas y los caminos forestales aumentaran considerablemente (contribuciones totales de 835 and 795 kg ha-1, respectivamente). Sin embargo, la contribución total desde el cauce para LUT durante el periodo estudiado (1.530 kg ha-1) permaneció similar a la de LUC. Los resultados de esta investigación demostraron que todo intento para reducir el impacto de las operaciones forestales en las cargas de sedimentos en cuencas en el área de estudio deben focalizarse en adoptar buenas prácticas de manejo para reducir la movilización de sedimentos desde las laderas y los caminos forestales.

ABSTRACT Background: During the past decade, the phenomenon of Oak decline has affected valuable Zagros Oak Forests in western Iran. Quercus brantii as the most important tree species of these forests has been damaged more than any other species. Many factors are involved in this phenomenon. The purpose of this study was to identify areas with high potential for decline and determine the most important factors affecting it. In this study, using multi-criteria evaluation methods based on the Geographic Information System (GIS) Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) method and fuzzy logic, the map of decline potential of two selected stands (Dalab and Cheghasabz) in Ilam Province was prepared to reveal the high-risk areas of decline. The analytical hierarchical process was used to determine the weight of the factors. Results: The results showed that both selected stands had decline potential. However, the Dalab stand at 25% and the Cheghasabz, at approximately 60% of the stand has an extreme potential for decline. Rainfall factors, pests, and diseases also have the greatest effect on Oak forest decline. Conclusion: Due to socio-economic problems such as land use change, fire, tourism, grazing, and pruning, the Cheghasabz is more prone to decline than the Dalab, which was a forest reserve. The multi-criteria evaluation model used in the study can be a guide in identifying high-risk areas in other parts of the Zagros forests. The large area of critical areas in these two regions reveals the need for planning to implement support operations to reconstruct damaged ecosystems.

Resumo O Trabalho desenvolveu se na zona de “El Franco”, município de Guisa, província de Granma, Cuba. O objectivo da investigação foi caracterizar elementos das operações no aproveitamento florestal da espécie Pinus maestrensis Bisse. Empregara se informação da base de dados do projeto de gestão florestal da empresa Agroflorestal Granma, um modelo digital do Terreno e um Sistema de Informação Geográfico Integrado de Gestão Florestal através do que calculou se a densidade da rede caminheira. Mediante a observação de campo classificou se o sistema organizativo de acópio e descreveram se as atividades de extração, recolha e carregamento. Como resultado se obtive que a área presenta o esquema em anelos, a área tem uma rede rodoviária composta por 23,3 km de estradas de 1ª, 2ª e 3ª categorias distribuídas em 35,7 %, 17,9 % e 46,4 % respectivamente com uma densidade total de 41 m/ha-1 e trilhos que não obedecem plenamente às características geométricas estabelecidas para as estradas florestais. As áreas de exploração florestal têm um padrão circular, com o abandono dos toros de dimensão comercial e a utilização de técnicas de manipulação da madeira que causam problemas de saúde e segurança, apresentando um sistema de abate insuficientemente planeado.

Abstract The study was carried out in the area of "El Franco", Guisa municipality, Granma province, Cuba. The objective of the research was to characterize elements of the operations in the forest exploitation of the species Pinus maestrensis Bisse. Information from the database of the forest management project of the Empresa Agroforestal Granma, a Digital Terrain Model and an Integrated Geographic Information System for Forest Management were used to calculate the density of the road network. Through field observation, the organizational collection system was classified and extraction, collection and loading activities were described. The result was that the area has a road network composed of 23,3 km of 1st, 2nd and 3rd category roads distributed in 35,7 %, 17,9 % and 46,4 % respectively with a total density of 41 m/ha-1 and trails that do not fully comply with the geometric characteristics established for forest roads. The logging areas have a ring pattern, with the abandonment of commercial-sized logs and the use of wood handling techniques that cause health and safety problems, showing an insufficiently planned harvesting system.

Resumen El trabajo se desarrolló en la zona de "El Franco", municipio Guisa, provincia Granma, Cuba. El objetivo de la investigación consistió en caracterizar elementos de las operaciones en el aprovechamiento forestal de la especie Pinus maestrensis Bisse. Se utilizó información de la base de datos del proyecto de ordenación forestal de la Empresa Agroforestal Granma, un Modelo Digital del Terreno y un Sistema de Información Geográfico Integrado de Gestión Forestal a partir del cual se calculó la densidad de la red caminera. Mediante observación de campo se clasificó el sistema organizativo de acopio y se describieron las actividades de extracción, acopio y carga. Como resultado se obtuvo que el área presenta una red vial compuesta por 23,3 km de caminos de 1ra, 2da y 3ra categoría distribuidos en un 35,7 %; 17,9 % y 46,4 % respectivamente con una densidad total de 41 m/ha-1 y vías de arrastre que no se ajustan en su totalidad a las características geométricas establecidas para los caminos forestales. Los acopiaderos presentan un esquema en anillos, con abandono de trozas de dimensiones comerciales y uso de técnicas de manipulación de la madera que ocasionan problemas de salud y seguridad evidenciando un sistema de aprovechamiento insuficientemente planificado.