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2.
Conserv Biol ; 35(1): 101-114, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33037677

RESUMEN

As humanity continues to alter the environment extensively, comprehending the effect of anthropogenic disturbances on the health, survival, and fitness of wildlife is a crucial question for conservation science. Many primate populations occupy suboptimal habitats prone to diverse anthropogenic disturbances that may be sources of acute and chronic stress. Quantification of glucocorticoid (GC) concentrations has repeatedly been used to explore the impact of disturbances on physiological stress. Although it is still debated, prolonged elevation of GC levels may impair reproduction, growth, and immune system activity of individuals. We quantified the effect of anthropogenic disturbances on physiological stress in primates with a global meta-analysis based on data from 26 articles, covering 24 distinct species in 13 different countries. Anthropogenic disturbances were classified into 6 distinct categories: habitat loss, habitat degradation, ongoing logging, hunting, tourism, and other human activities. We calculated effect sizes (Hedges' g) with the standardized mean difference in GC concentrations between primates affected by human activity and their undisturbed conspecifics. We ran random-effects models and subgroup analyses to estimate the overall effect as well as a cumulative effect size for each disturbance category. Overall, primates inhabiting sites subject to anthropogenic disturbances exhibited significantly higher GC levels (g = 0.60; 95% CI: 0.28-0.93). Habitat loss and hunting were overall associated with increased GC concentrations, whereas the cumulative effects of the other disturbances were not statistically significant. Biologically, high GC levels may increase fitness by enabling individuals to overcome the challenges linked to anthropogenic disturbances. However, primates in disturbed environments may have sustained elevated GC levels. To strengthen future research, it is necessary to control confounding factors systematically (e.g., diet, reproductive status, predatory pressure, and resource availability) and improve understanding of the link between GC levels and the health, fitness, and survival of animals.


Asunto(s)
Conservación de los Recursos Naturales , Actividades Humanas , Animales , Ecosistema , Primates , Estrés Fisiológico
5.
Microbiol Res ; 231: 126371, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31734584

RESUMEN

Eleven soil samples were collected from different plantations at the Forestry Model Base, Northeast Forestry University, China (45°43'10″N, 126°37'15″E), and 122 Trichoderma strains (T1-T122) were isolated. Nine Trichoderma species were identified based on morphological and molecular classification methods. The diversity of woody fungi was analyzed based on the type and quantity of Trichoderma spp. in the soil samples isolated from each plantation. Subdominant T. pseudoharzianum T17 (TpsT17) was screened and its biocontrol potential against Fusarium oxysporum CFCC86068 (Fox68) and growth promotion of Populus davidiana × P. alba var. pyramidalis (PdPap) seedlings were investigated. Compared with PdPap + Fox68 treatment, PdPap + TpsT17 + Fox68 treatment had an obvious antagonistic effect on Fox68 based on the status of roots and stomata of the poplar seedlings. In addition, pretreatment with TpsT17 increased catalase activity 14-fold and decreased hydrogen peroxide and malondialdehyde concentrations 2.57- and 7-fold, respectively, in the PdPap + TpsT17 + Fox68 treatment compared with the PdPap + Fox68 treatment. The transcription levels of PR1, JAZ6751, MYC2, MP, and JAR1 in PdPap + TpsT17+Fox68-treated plants were upregulated 5.75-, 5.63-, 14.88-, 8.24-, and 10.45-fold, respectively, at 3 d, while LAX2 exhibited little change in comparison with the level in PdPap + Fox-treated plants. TpsT17 was detected in the roots and stems of PdPap + TpsT17- and PdPap + TpsT17+Fox68-treated PdPap 28 d after inoculation, which demonstrated the endogenous capacity of TpsT17.


Asunto(s)
Endófitos/aislamiento & purificación , Fusarium/crecimiento & desarrollo , Populus , Trichoderma , Antibiosis , Antifúngicos , Agentes de Control Biológico , Catalasa/metabolismo , ADN Espaciador Ribosómico , Endófitos/genética , Endófitos/metabolismo , Agricultura Forestal , Genes Fúngicos , Micosis/microbiología , Filogenia , Enfermedades de las Plantas/microbiología , Inmunidad de la Planta , Populus/enzimología , Populus/microbiología , Plantones/metabolismo , Microbiología del Suelo , Trichoderma/genética , Trichoderma/aislamiento & purificación , Trichoderma/metabolismo
6.
Sci Rep ; 9(1): 9766, 2019 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-31278353

RESUMEN

We used the 12th generation of the Cunninghamia (C.) lanceolata tissue culture seedlings, and white light emitting diode (LED) light as control (CK). We applied five composite LED light treatments, red-blue 4:1, 8:1 (4R1B and 8R1B), red-blue-purple 8:1:1 (8R1B1P), and red-blue-purple-green 6:1:1:1, 8:1:1:1 (6R1B1P1G and 8R1B1P1G), to study the effects of light quality on root growth characteristics and antioxidant capacity of C. lanceolata tissue culture seedlings. The results showed that: (1) rooting rate, average root number, root length, root surface area, and root activity were higher with 6R1B1P1G and 8R1B1P1G treatments compared to 4R1B, 8R1B, 8R1B1P and CK treatments; and the root growth parameters under the 8R1B1P1G treatment were as high as 95.50% for rooting rate, 4.63 per plant of the average number of root, 5.95 cm root length, 1.92 cm2 surface area, and 145.56 ng/(g·h) root activity, respectively. (2) The composite lights of 4R1B, 8R1B, 8R1B1P, 6R1B1P1G, and 8R1B1P1G are beneficial for the accumulation of soluble sugar content (SSC) and soluble protein content (SPC), but not conducive for the increase of free proline content (FPC); the plants under 6R1B1P1G and 8R1B1P1G treatments had higher superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX) activity and lower malondialdehyde (MDA), polyphenol oxidase (PPO) activity. (3) Redundancy analysis showed that POD activity positively correlated with root activity; SPC, SOD and CAT activities positively correlated with root growth parameters; while SSC, MDA content, APX and PPO activities negatively correlated with root growth parameters. These results suggest that the responses of root growth and antioxidant capacity of the C. lanceolata tissue culture seedlings to different light qualities vary. The relationship between root growth parameters and antioxidant capacity was closely related. Red-blue-purple-green was the most suitable composite light quality for root growth of C. lanceolata tissue culture seedlings, and 8:1:1:1 was the optimal ratio, under which the rooting rate, root activity and root growth of tissue culture seedlings peaked.


Asunto(s)
Antioxidantes/metabolismo , Cunninghamia/fisiología , Cunninghamia/efectos de la radiación , Luz , Raíces de Plantas/fisiología , Raíces de Plantas/efectos de la radiación , Plantones/fisiología , Plantones/efectos de la radiación , Agricultura Forestal , Fitomejoramiento , Desarrollo de la Planta/efectos de la radiación
7.
Rev. biol. trop ; 67(1): 164-181, Jan.-Mar. 2019. tab, graf
Artículo en Español | LILACS | ID: biblio-1041901

RESUMEN

Resumen Los estudios detallados para comprender como los bosques neotropicales se reestablecen en el tiempo, a través de la sucesión secundaria aún resultan necesarios. Entre los mecanismos de regeneración que actúan en los bosques tropicales, el rebrote de árboles predomina en especies leñosas, con la ventaja de reiniciar el crecimiento de raíces establecidas, que permiten restituir el dosel forestal. El objetivo de este estudio fue identificar y cuantificar las especies arbóreas con capacidad de rebrote en distintas etapas de la sucesión secundaria (barbecho) después del sistema agrícola tradicional de milpa, comparadas con las comunidades del bosque tropical predominante en la Reserva de la Biósfera de Calakmul, y cómo influyen estas especies en la recuperación de la composición de este ecosistema. Se calculó el porcentaje de especies con y sin rebrote para cada etapa sucesional. Se registraron 13 972 individuos (32 % con rebrote y 68 % sin rebrote) y 168 especies (79 % con rebrote y 21 % sin rebrote), el porcentaje de individuos con rebrote va disminuyendo conforme avanza la edad de la sucesión. El número de individuos con rebrote y la composición de especies fueron significativamente diferentes entre etapas. Se puede concluir que la mayoría de especies arbóreas del bosque en Calakmul, presentan la capacidad de rebrotar, lo cual tiene influencia en el rápido proceso sucesional del bosque después de la roza-tumba y quema, restituyendo la cobertura y estructura forestal, así como la composición de las especies originales.(AU)


Abstract Detailed studies to understand recovering of Neotropical forests over time, through secondary succession, are still necessaries. Between acting mechanisms of regeneration in the tropical forests, the arboreal resprout predominates in woody species, with the advantage of restart the growth from still rooting plants, allowing the restoring of forest canopy. The study aim was to identify and quantify the tree species with resprouting capacity in different stages of secondary succession (tree-fallow) after the traditional milpa agricultural system, compared with tropical forest communities in the Calakmul Biosphere Reserve and, enlightening how these species influences the recovery of the composition of this ecosystem. Was calculated the proportions of species with or without resprouting by successional stage. There were 13 972 individuals (32 % resprouting and 68 % not resprouting) and 168 species (79 % resprouting and 21 % not resprouting), the percentage of individuals regrowing decreases as the successional stage progresses. The number of individuals resprouting and species composition were significantly different between successional stages. In conclusion, mostly arboreal species in the region of Calakmul, can regrow, which influences the successional development of the forest after slash-and-burn, helping to restore the coverage, structure, as well as species composition original.(AU)


Asunto(s)
Árboles , Cultivos Agrícolas , Ecosistema Tropical , México
8.
J Agromedicine ; 24(2): 197-204, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30624154

RESUMEN

BACKGROUND: Logging is recognized as one of the most dangerous industries in the United States (US), ranking among those with the highest occupational injury and fatality rates. Although logging operations in the Southeastern US have lower rates of injuries and fatalities compared to other regions of the US, due in part to the use of large machinery to fell timber as opposed to chainsaw felling, safety hazards continue to persist. The hazards present in the logging cut sites in which loggers operate may result in worker injury, illness, or fatality. Our objective was to develop, deliver, and evaluate a safety management and leadership training among logging contractors and supervisors using mobile tablets as a personal learning environment. METHODS: A safety leadership and management training vignette was developed based on previously collected focus group needs assessment data. A non-random sample of 31 male logging supervisors received the safety leadership and management training on a mobile tablet. Kirkpatrick Levels 1, 2, and 3 training effectiveness evaluations were performed. RESULTS: A statistically significant large effect size suggests safety knowledge was gained among training participants when comparing post-test scores to pre-test scores (Level-2). Participants rated their training experience favorably (Level-1), and applied knowledge gained from the training throughout their weekly work activities three months after training (Level-3). CONCLUSION: Our findings suggest the utilization of mobile learning techniques can be an effective means to deliver safety management and leadership training content to logging contractors and supervisors. Future trainings should be linguistically and literacy-level appropriate, as well as comprehensive in nature, including meaningful and relevant content. Our observations support the use of mobile devices as just one component of a more comprehensive health and safety management program for workers in the logging industry.


Asunto(s)
Computadoras de Mano , Agricultura Forestal/educación , Liderazgo , Administración de la Seguridad/métodos , Adulto , Grupos Focales , Humanos , Masculino , Persona de Mediana Edad , Enseñanza/normas
10.
J Sci Food Agric ; 99(1): 191-198, 2019 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-29855053

RESUMEN

BACKGROUND: In Mediterranean grazed woodlands, microclimate changes induced by trees influence the growth and development of the understory, although very little is known about its polyphenolic composition in relation to light intensity. We investigated the bioactive compounds and antioxidant capacity of different legume-based swards and variations as a result of full sunlight and partial shade. The research was carried out in a cork oak agrosilvopastoral system in Sardinia. RESULTS: The highest values of (1,1-diphenyl-2-picrylhydrazyl) (DPPH) reached 7 mmol Trolox equivalent antioxidant capacity 100 g-1 dry weight (DW), total phenolics 67.1 g gallic acid equivalent kg-1 DW and total flavonoids 7.5 g catechin equivalent kg-1 DW. Compared to full sunlight, partial shade reduced DPPH values by 29% and 42%, and the total phenolic content by 23% and 53% in 100% legume mixture and semi-natural pasture, respectively. Twelve phenolic compounds were detected: chlorogenic acid in 80% legume mixture (partial shade) and verbascoside in pure sward of bladder clover (full sunlight) were the most abundant. CONCLUSION: Light intensity significantly affected antioxidant capacity, composition and levels of phenolic compounds. The results of the present study provide new insights into the effects of light intensity on plant secondary metabolites from legume-based swards, highlighting the important functions provided by agroforestry systems. © 2018 Society of Chemical Industry.


Asunto(s)
Antioxidantes/química , Fabaceae/química , Fabaceae/efectos de la radiación , Polifenoles/química , Fabaceae/crecimiento & desarrollo , Agricultura Forestal , Italia , Luz
11.
Salud colect ; 14(4): 695-711, oct.-dic. 2018. tab
Artículo en Español | LILACS-Express | LILACS | ID: biblio-985866

RESUMEN

RESUMEN En la Argentina, en las últimas décadas, la actividad forestal ha evidenciado una importante expansión promovida por el Estado a través de incentivos que alentaron la implantación de especies forestales. En este artículo se examinan las condiciones laborales de un número de trabajadores forestales de las tres principales provincias productoras de madera de la Argentina (Corrientes, Misiones y Entre Ríos). Con los datos de la Encuesta sobre Empleo, Protección Social y Condiciones de Trabajo de los Asalariados Agrarios se efectuó un procesamiento y análisis de la información referida a los trabajadores forestales de las provincias mencionadas (n=113). A su vez, la realización de entrevistas en profundidad a trabajadores (n=30) y contratistas forestales (n=8), entre 2010 y 2014, contribuyó a explicar el fenómeno estudiado en su totalidad. Los resultados obtenidos muestran que más del 50% de los trabajadores considera estar expuesto a condiciones desfavorables del medio ambiente físico de trabajo. El 16% ha tenido un accidente laboral en el último año. La alta precariedad de este tipo de empleo, sumada a las formas de contratación (tercerización), dificulta la identificación de acciones a seguir para revertir los procesos analizados.


ABSTRACT In the last decades in Argentina, forestry activity has seen an important expansion, promoted by the State through incentives encouraging the implantation of forest species. This article examines the working conditions of a number of forestry workers in the three main timber producing provinces of Argentina (Corrientes, Misiones and Entre Ríos). Using data from the Survey on Employment, Social Protection and Labor Conditions of Salaried Agricultural Workers, information on forest workers of the aforementioned provinces was processed and analyzed (n=113). In addition, in-depth interviews with workers (n=30) and forest contractors (n=8), carried out from 2010-2014, contributed to the explanation of the studied phenomenon as a whole. The results show that more than 50% of workers consider themselves exposed to unfavorable conditions in the physical working environment, with 16% having had a work accident in the last year. The high precariousness of this type of employment, in conjunction with the forms of contracting (outsourcing), makes it difficult to identify actions to be taken to reverse the processes analyzed.

12.
PLoS One ; 13(10): e0204511, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30286111

RESUMEN

There is growing recognition that with sympathetic management, plantation forests may contain more biodiversity than previously thought. However, the extent to which they may support bat populations is contentious. Many studies have demonstrated active avoidance of coniferous plantations and attributed this to the lack of available roost sites and low invertebrate density. In contrast, other work, carried out in plantation dominated landscapes have shown that certain bat species are able to exploit these areas. However, the extent to which bats use plantations for roosting and foraging, or simply move through the plantation matrix to access more favourable sites is unclear. We radio tracked female Pipistrellus pygmaeus over two summers to establish the extent to which individual bats use Sitka Spruce plantations in southern Scotland for foraging and roosting and assess the implications for felling operations on bats. Maternity roosts identified (n = 17) were in all in buildings and most were large (> 500 individuals). We found no evidence of bats roosting in mature Sitka Spruce crop trees, although several bats used roosts in old or dead beech and oak trees as an alternative to their main maternity roost. Home ranges were much larger (mean 9.6 ± 3.12 km2) than those reported from other studies (0.6-1.6 km2), and it is likely that roost availability rather than food abundance constrains P. pygmaeus use of Sitka Spruce plantations. At the landscape scale, most individuals selected coniferous habitats over other habitat types, covering large distances to access plantation areas, whilst at a local scale bats used forest tracks to access water, felled stands or patches of broadleaf cover within the plantation. Sitka Spruce plantations support a high abundance of Culicoides impuctatus, the Highland midge which may act as a reliable and plentiful food source for females during lactation, an energetically expensive period. The use of felled stands for foraging by bats has implications for forest management as wind turbines, following small-scale felling operations, are increasingly being installed in plantations; wind turbines have been associated with high bat mortality in some countries. Decisions about siting wind turbines in upland plantations should consider the likelihood of increased bat activity post felling.


Asunto(s)
Quirópteros , Conducta Predatoria , Animales , Culicomorpha , Femenino , Agricultura Forestal , Bosques , Vivienda , Humanos , Lactancia , Conducta Materna , Actividad Motora , Energía Renovable , Descanso , Escocia , Análisis Espacial , Árboles , Agua , Tecnología Inalámbrica
14.
Rev. biol. trop ; 66(1): 58-69, Jan.-Mar. 2018. graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-897654

RESUMEN

Resumen Hypsipyla grandellaes una plaga forestal clave en América Latina y el Caribe, donde ha impedido todo intento de establecer plantaciones comerciales de caobas (Swieteniaspp.) y cedros (Cedrelaspp.). En la búsqueda de métodos de manejo de sus larvas, que sean preventivos y rentables, así como basados en recursos de la flora tropical, fue evaluada la actividad fagodisuasiva del extracto crudo y de cuatro particiones fitoquímicas (agua, hexano, diclorometano y acetato de etilo) de la flor de reina de la noche,Brugmansia candida(Solanaceae). Se efectuaron bioensayos de laboratorio con concentraciones crecientes del extracto crudo (0.1; 0.3; 1.0; 3.2 y 10.0 % m/v) y con cada una de las particiones (según el rendimiento del proceso de particionamiento). Se utilizó un diseño de bloques completos al azar, con cuatro repeticiones, y se expusieron larvas de instar III de H. grandellaa discos de cedro amargo (Cedrela odorata) impregnados con el respectivo tratamiento, por 24 h. Se midió el porcentaje de consumo de cada disco. El extracto crudo y la partición de hexano, mostraron un evidente efecto fagodisuasivo a partir de concentraciones de 1.0 % y 0.122 % m/v, respectivamente. También se realizó un bioensayo para comparar una sola concentración (0.38 % m/v) del alcaloide escopolamina, el cual redujo en 90% el consumo con respecto a los testigos. Asimismo, se evaluó la mortalidad y los efectos subletales en larvas expuestas al extracto crudo, la partición de hexano y la escopolamina, pero no hubo evidencias de ellos, lo que confirmó su acción fagodisuasiva. Además, se realizó un tamizaje fitoquímico del extracto crudo, y mediante pruebas cualitativas se determinó que los alcaloides, taninos, triterpenos y cumarinas fueron los metabolitos secundarios más importantes. Finalmente, se confirmó la presencia de la escopolamina tanto en el extracto crudo como en la partición de hexano, mediante el método de cromatografía de gases acoplado a un espectrómetro de masas (GC-MS). Se recomienda preparar una formulación de escopolamina más algunos coadyuvantes, y evaluar su eficacia en condiciones de invernadero, como un primer paso para avanzar en el desarrollo de un fagodisuasivo comercial.


Abstract Hypsipyla grandella is a key forest pest in Latin America and the Caribbean, where it has precluded attempts to establish commercial plantations of mahoganies (Swieteniaspp.) and cedars (Cedrelaspp.). In the search for methods to manage its larvae, being both preventative and cost-effective, as well as based upon resources from tropical flora, the crude flower extract of angel's trumpet, Brugmansia candida, as well as four partitions thereof (water, hexane, dichlorometane, and ethyl acetate), were tested for phagodeterrence. Laboratory bioassays involved increasing concentrations of the crude extract (0.1, 0.3, 1.0, 3.2 and 10.0 % w/v) as well as each one of the partitions (in accordance to the yield obtained from the partitioning process). A randomized complete block design, with four replicates, was used. H. grandellainstar III larvae were exposed for 24 h to Spanish cedar (Cedrela odorata) leaf discs dipped into the respective treatment, after which disc consumption was measured. Strong phagodeterrence was detected at concentrations as low as 1.0 % y 0.122 % w/v for the crude extract and the hexane partitions, respectively. In addition, a single bioassay was performed to compare a single concentration (0.38 % w/v) of the alkaloid scopolamine, which reduced consumption in 90 % with respect to the controls. Also, mortality and sublethal effects were assessed in larvae exposed to the crude extract, the hexane partition and scopolamine, with no evidence for them, which confirmed their phagodeterrence. Moreover, the crude extract was submitted to a phytochemical screening by means of a number of qualitative tests, which showed that alkaloids, tannins, triterpenes and cumarins were the most important secondary metabolites. Finally, the presence of scopolamine was confirmed in both the crude extract and the hexane partition, by means of the gas chromatography-spectrometry (GC-MS) analytical method. It is recommended to prepare a formulation of scopolamine plus some adjuvants, in order to test its effectiveness under greenhouse conditions, as a first step to advance in the development of a commercial phagodeterrent. Rev. Biol. Trop. 66(1): 58-69. Epub 2018 March 01.

15.
Rev. luna azul ; 4601 enero 2018.
Artículo en Inglés, Español | LILACS | ID: biblio-1007103

RESUMEN

El artículo tiene por objetivo avanzar en la comprensión de la política de protección de bosques que tiene lugar en Argentina desde mediados de siglo XX. En particular, se detiene en las condiciones de emergencia, debate y sanción de la Ley N° 13.273 de "Defensa de la Riqueza Forestal" aprobada en el año 1948, propuesta legislativa que formó parte del Plan de Gobierno previsto para el primer quinquenio del gobierno peronista que fue presentado en 1946. Para la consecución de los objetivos planteados se emplearon diversidad de materiales y fuentes documentales: colecciones de libros, material legislativo y estadístico, publicaciones de organismos nacionales y/o asociaciones vinculadas a la producción forestal, entre las principales. Se exponen los antecedentes legales, institucionales y productivos en torno a la actividad forestal desde fines de siglo XIX, para luego avanzar en el contexto político y socioeconómico; las características del proyecto y de los debates y actores que se sucedieron en las disputas por la sanción e implementación de una ley que propendiera a la defensa de la riqueza forestal argentina (explotada y depredada desde décadas previas sin un orden legal y/o institucional específico). Entre los principales resultados y conclusiones, se afirma que desde fines de siglo XIX las prácticas hegemónicas que delinearon el uso y ocupación del territorio en Argentina no tuvieron en cuenta al bosque en su amplitud y variedad de potencialidades ofrecidas, sino que han estado predominantemente signadas por un patrón de tipo extractivo y cortoplacista que conllevó a su progresiva destrucción, sobreexplotación y degradación, en desmedro de la conservación y regeneración de las masas boscosas. La Ley N° 13.273 se constituyó entonces en un hito en el tratamiento legal de los bosques en el país, no obstante la continuidad de la deforestación y degradación que se registran hasta la actualidad en Argentina.


The purpose of this article is to make progress in the understanding of forest protection policies implemented in Argentina since the mid-20th century. In particular it examines the emergency, debate and sanction of Act No. 13,273 of 1948 "Defense of Forest Wealth" approved in 1948 as a legislative proposal part of the Government Plan foreseen for the first quinquennium of the Peronist government which was introduced in 1946. In order to achieve the proposed objectives, a diversity of materials and documentary sources were used including, among others, a collection of books, legislative and statistical sources, and publications by national organizations and/or associations linked to forest production. Legal, institutional and productive antecedents of forest activity since the late 20th century are presented to move forward to the political and socioeconomic context, the characteristics of the project and the debates, and the actors that followed in the disputes for the passing and implementation of a law tending towards the defense of forest wealth in Argentina (for decades exploited and depredated since previous decades under no specific legal and/or institutional order). Among the main findings and conclusions, it is affirmed that, since the end of the 19th century, the hegemonic practices that delineated the use and occupation of the territory in Argentina did not take into account the forest in all its vastness and variety of available potential but have been rather characterized by an extractive and short-term pattern that led to its progressive destruction, overexploitation and degradation at the expense of the conservation and regeneration of forest masses. The 13,273 Act has since then become a milestone in the legal treatment of forests in the country, in spite of the continuous deforestation and degradation of forest masses that can today still be seen in Argentina.


Asunto(s)
Bosques
16.
Salud Colect ; 14(4): 695-711, 2018.
Artículo en Español | MEDLINE | ID: mdl-30726447

RESUMEN

In the last decades in Argentina, forestry activity has seen an important expansion, promoted by the State through incentives encouraging the implantation of forest species. This article examines the working conditions of a number of forestry workers in the three main timber producing provinces of Argentina (Corrientes, Misiones and Entre Ríos). Using data from the Survey on Employment, Social Protection and Labor Conditions of Salaried Agricultural Workers, information on forest workers of the aforementioned provinces was processed and analyzed (n=113). In addition, in-depth interviews with workers (n=30) and forest contractors (n=8), carried out from 2010-2014, contributed to the explanation of the studied phenomenon as a whole. The results show that more than 50% of workers consider themselves exposed to unfavorable conditions in the physical working environment, with 16% having had a work accident in the last year. The high precariousness of this type of employment, in conjunction with the forms of contracting (outsourcing), makes it difficult to identify actions to be taken to reverse the processes analyzed.


Asunto(s)
Accidentes de Trabajo/estadística & datos numéricos , Agricultura Forestal , Salud Laboral/estadística & datos numéricos , Adulto , Argentina , Femenino , Humanos , Entrevistas como Asunto , Masculino , Persona de Mediana Edad , Riesgo
17.
Cienc. tecnol. salud ; 5(2): 136-150, 2018. ^c27 cmilus
Artículo en Inglés | LILACS | ID: biblio-987186

RESUMEN

The Northern Humid Guatemalan Lowlands contains a significant diversity of tree species, including some valuable-timber producers; these species are threatened by commercial overexploitation and habitat loss due to deforestation. The cultivation of these species in forest and agroforest plantations is a potentially viable option for balancing their conservation and commercial harvesting, something that has been promoted with Government Incentives in Guatemala during the past two decades. However, these species have not been widely planted, among other constraints, because knowledge on their ecological requirements and silviculture is scarce. A characterization of monoculture and mixed plantations with 14 native valuable-timber species was made in the Humid Lowlands of Northern Guatemala, analyzing for each species frequency of association and accompanying species, planted area, the main ecological features and growth rates. To gather information, we combined field observation and measurements with interviews and literature review. Based on our survey, main management challenges for cultivation of the species were identified and described. Valuable-timber native trees could potentially be sustainably cultivated in the study zone in different types of forest plantations and agroforestry schemes of coffee, cacao, cardamom and cattle; considering their suitability to fit in diversified systems, growth performance and farmer's preferences, Swietenia macrophylla, Cedrela odorata, Tabebuia donnell-smithii, Calophyllum brasiliense and Cordia alliodora were the species with the higher potential for inclusion in plantations. However, several unsolved problems continue restricting the cultivation of these species in plantations; therefore, is essential a careful design and management.


Las Tierras Bajas y Húmedas del Norte de Guatemala contienen diversidad relevante de especies arbóreas, incluyendo algunas de madera valiosa; estas especies están amenazadas por sobre explotación comercial de su madera y deforestación. El cultivo de estas especies en plantaciones forestales y agroforestales es una opción potencialmente viable para equilibrar su conservación y aprovechamiento, lo cual ha sido promovido en Guatemala durante las dos décadas pasadas. Sin embargo, estas especies no se cultivan extensivamente, entre otras limitantes, debido al escaso conocimiento sobre su ecología y silvicultura. Se caracterizaron plantaciones puras y mixtas con 14 especies nativas maderables valiosas en Tierras Bajas y Húmedas del Norte de Guatemala, analizando para cada especie, presencia de especies, superficies plantadas, rasgos ecológicos y crecimiento. Para obtener información se combinó observaciones de campo, mediciones, entrevistas, consultas de archivo y revisión bibliográfica. Se identifican y describen los principales desafíos de manejo para cultivar las especies. Las especies nativas de madera valiosa podrían potencialmente ser cultivadas de manera sostenible, en diferentes tipos de plantación forestal y agroforestal con café, cacao, cardamomo y ganadería; considerando idoneidad para encajar en sistemas diversificados, tasas de crecimiento y preferencias de productores, Swietenia macrophylla, Cedrela odorata, Tabebuia donnell-smithii, Calophyllum brasiliense y Cordia alliodora fueron las especies que mostraron mayor potencialidad para ser incluidas en plantaciones en la zona. Sin embargo, aún persisten diferentes aspectos no resueltos que limitan el cultivo de estas especies en plantación, requiriéndose un cuidadoso diseño y manejo.


Asunto(s)
Especies en Peligro de Extinción/estadística & datos numéricos , Explotación de Recursos Naturales/efectos adversos , Madera/economía , Cultivos Agrícolas , Agricultura Forestal/economía
18.
Acta biol. colomb ; 23(2): 170-178, 2018. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-949326

RESUMEN

ABSTRACT The present study describes composition and trophic structure, and assesses the effect of environmental temperature and rainfall on the pattern of nocturnal activity of understory bats in an Andean forest, in the first half of the night. Seven sampling events were conducted, lasting six nights each one. Ten mist nets were used to capture bats, which were checked every hour between 18:00 and 00:00 hours. Bat species, sex and capture time were registered. In addition, environmental temperature and rainfall were also recorded during sampling. The bat assemblage of the understory of the study area was represented mostly by frugivore species, within this guild there was a lower richness of nomadic than sedentary species. For the first half of the night, bat activity peaked between 18:00 and 19:00 hours and declined to a minimum level between 22:00 and 23:00 hours. The most accurate model to explain variation in bat captures included only the effect of air temperature, which positively affected the number of captures. In conclusion, for the sampled period the activity of the bat assemblage in the study area was not related to rainfall and exhibited a slight but significant relationship with air temperature.


RESUMEN En el presente trabajo se describe la composición y estructura trófica, y se evalúa el efecto de la temperatura ambiental y la precipitación sobre el patrón de actividad nocturna de los murciélagos de sotobosque que habitan que un bosque Andino, para la primera mitad de la noche. Para esto se realizaron siete campañas de muestreo, con una duración de seis noches cada una, en las que se utilizaron diez redes de niebla que operaron entre las 18:00 y 00:00 horas, siendo revisadas cada hora. Además, se registró la temperatura ambiental y la precipitación durante los eventos de muestreo. El ensamblaje de murciélagos de sotobosque del área de estudio estuvo representado principalmente por especies frugívoras, y dentro de este gremio, se registró una menor riqueza de especies nómadas que sedentarias. La actividad de los murciélagos, para la primera mitad de la noche, fue máxima entre las 18:00 y 19:00 horas, disminuyendo hasta alcanzar una actividad mínima entre las 22:00 y 23:00 horas. El modelo más adecuado para explicar la variación en las capturas de murciélagos incluyó sólo el efecto de la temperatura ambiental, la cual afectó positivamente el número de capturas. En conclusión, para el periodo evaluado, la actividad del ensamble de murciélagos de sotobosque en el área de estudio no se relacionó con la precipitación y exhibió relación leve pero significativa con la temperatura ambiental.

19.
Conserv Biol ; 31(6): 1257-1270, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-29030915

RESUMEN

Political and economic transitions have had substantial impacts on forest conservation. Where transitions are underway or anticipated, historical precedent and methods for systematically assessing future trends should be used to anticipate likely threats to forest conservation and design appropriate and prescient policy measures to counteract them. Myanmar is transitioning from an authoritarian, centralized state with a highly regulated economy to a more decentralized and economically liberal democracy and is working to end a long-running civil war. With these transitions in mind, we used a horizon-scanning approach to assess the 40 emerging issues most affecting Myanmar's forests, including internal conflict, land-tenure insecurity, large-scale agricultural development, demise of state timber enterprises, shortfalls in government revenue and capacity, and opening of new deforestation frontiers with new roads, mines, and hydroelectric dams. Averting these threats will require, for example, overhauling governance models, building capacity, improving infrastructure- and energy-project planning, and reforming land-tenure and environmental-protection laws. Although challenges to conservation in Myanmar are daunting, the political transition offers an opportunity for conservationists and researchers to help shape a future that enhances Myanmar's social, economic, and environmental potential while learning and applying lessons from other countries. Our approach and results are relevant to other countries undergoing similar transitions.


Asunto(s)
Conservación de los Recursos Naturales/legislación & jurisprudencia , Agricultura Forestal/legislación & jurisprudencia , Bosques , Política , Biodiversidad , Mianmar
20.
Yi Chuan ; 39(10): 939-946, 2017 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-29070489

RESUMEN

Undergraduate students majoring in forestry generally reflect that genetics is one of the most difficult compul-sory courses, because the traditional teaching method is difficult to satisfy their needs. According to the theoretical charac-teristics of forestry and actual demands of the students, in the light of teaching and research experience in recent years, we adopted a series of typical genetic cases such as 'opening coffin to identify relatives', stem-throne of Lycium ruthenicum Murr, and magic powers in Harry Potter. Our practices revealed that the case teaching in genetics could train good personality traits, learning abilities and creativity of the students, stimulate their interests and initiatives in learning, and increase systematic learning.


Asunto(s)
Agricultura Forestal/educación , Genética/educación , Enseñanza , Humanos , Estudiantes
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