Papers by Marta Leonor de Viana
Ecología austral, Jun 1, 2003
Revista De Biologia Tropical, Oct 9, 2015
The chiropteran reproductive parterns in tropical zones have been associated with food seasonalit... more The chiropteran reproductive parterns in tropical zones have been associated with food seasonality by synchronization between parturition time and the lrighest environmental productivity. In the common vampire ba, ( Desmodus rotundus ) whose food (catde blood), is widely available year round, reproductive seasonality mus! be absent. In order 10 test (his hypothesis, a natural cave colony in the Salta Province (Argentina), was studied. The vampire bate were captured with a mist let placed al the cave enlrance. Reproductive condition in females (pregnancy, absence of pregnancy or lactation) and in males (abdonrinal or serotal tests) was seasonalty assessed with respect to temperature (surnmer, autom.n, winter, spring) ano hmnidity (dry and wet seasons). Association between female reproductive condition and seasonality was detected. Tbe proportion of pregnancy and lactation were higher during spring and summer as well as al !he wet season. In males, there was no association between these variables. Although reproduction is continuous througout ihe year, ir shows a marked seasonality. This pattern can be considered a result of environmcntal conditions (temperature ano hunridity) instead of food availability
PubMed, Mar 1, 2001
The tree Caesalpinia paraguariensis grows in the Chaco region, Argentina. Fruits are indehiscent ... more The tree Caesalpinia paraguariensis grows in the Chaco region, Argentina. Fruits are indehiscent with many seeds. This species is an important source of wood and the fruits are consumed by cattle in Salta province. We studied seed germination under chemical, mechanical and biological scarification. Seeds from controls (without scarification) and those with biological scarification had a smaller (and similar) germination rate. The non-germinated seeds from biological treatments were mechanically scarified and their germination rate was similar to others under the mechanical treatment. Passage by digestive tracts would not enhance germination because viable seeds are still dormant due to their hard coats.
Avances en Energías Renovables y Medio Ambiente, 2009
Anales del Museo de Historia Natural de Valparaíso, 1987
Ecología austral, May 1, 2022
Revista De Biologia Tropical, Oct 9, 2015
Age estimation methods in the common vampire bat ( Desmodus rotundus ) were compared on 81 indivi... more Age estimation methods in the common vampire bat ( Desmodus rotundus ) were compared on 81 individuals from a natural cave in Ampascachi, Salta province (Argentina). Age was assessed by counting incisor growth lines in the root cementum. This estimation was compared with forearm and tibia lenght and dentinecementum and percentage of dentine attrition indices. Age estimation by both forearm and tibia lenght were less reliable (Pe8ISon r = 0.29 and 0.33 respectively) than dentine attrition and dentine-cementum indices (r = -0.90 and 0.88 respectively). McNemarand Cohen-Kappa tests showed that dentine attrition index had the best fit with aging by growth lines
Anales del Museo de Historia Natural de Valparaíso, 1987
DOAJ (DOAJ: Directory of Open Access Journals), Mar 1, 2013
Desiccation tolerance in seeds of Prosopis ferox and Pterogyne nitens (Fabaceae). The high number... more Desiccation tolerance in seeds of Prosopis ferox and Pterogyne nitens (Fabaceae). The high number of endemisms and species diversity together with the accelerated biodiversity loss by deforestation, especially in North Western Argentina, points out the need to work on species conservation combining ex situ and in situ strategies. The aim of this work was to study the desiccation tolerance in seeds of P. ferox and P. nitens for long term ex situ conservation at the Germplasm Bank of Native Species (BGEN) of the National University of Salta (Argentina). The fruits were collected from ten individuals in P. ferox at the National Park Los Cardones and from two sites (Orán and Rivadavia) for P. nitens. Desiccation tolerance was assessed following previous established methodologies. The moisture content (MC) of the seeds was determined by keeping them in oven at 103°C and weighting the samples at different intervals till constant weight. Germination essays were carried out with two treatments (control and scarification), with different seed MC (fresh, 10-12%, 3-5%) and in desiccated seeds (3-5% MC) stored six months at-20ºC. The MC in P. ferox seeds was 14.2% and 10% in P. nitens, for both populations studied. Percentage germination in P. ferox was higher in the scarification treatments (<82%). The difference between treatments increased with the reduction in MC and the storage for six months at-20°C. Fresh seeds of P. nitens do not need scarification treatment, but it is required with the reduction in MC and storage. Mean germination percentage of desiccated seeds stored six months at-20°C was similar in both populations and greater than 82%.We concluded that both species are probably orthodox because seeds tolerated desiccation to 3-5% and storage for six months at-20°C.
Revista De Biologia Tropical, Feb 9, 2016
En una area de 150 ha en el Valle de Tin Tin, provincia de Salta, Argentina, se estudio la densid... more En una area de 150 ha en el Valle de Tin Tin, provincia de Salta, Argentina, se estudio la densidad, estructura de la poblacion, proporcion sexual, frecuencia de colas regeneradas y periodo de actividad de la lagartija Liolaemus darwinii . La densidad fue maxima en mayo de 1989 (41 individuos/ha) y minima en abril de 1990 (4 individuos/ha). Los infantiles se reclutan en otono, constituyendo el 49 % (mayo 1989), el 75% (abril 1990) y el 66% (mayo 1990) de la poblacion. Los juveniles, ausentes en abril, comienzan a incorporarse a partir de los infantiles en mayo. La densidad de los adultos es baja todo el ano y en verano su proporcion es maxima (42%). La proporcion sexual fue 1: 1 en todas las estaciones del ano. Su periodo diario de actividad es maximo en las horas del medio dia. Parece existir una preferencia de L. darwini por L. divaricata , una planta cuya morfologia y distribucion le proporcionan un refugio mas adecuado y una mayor disponibilidad de alimento por unidad de espacio recorrido. La frecuencia de autotomia fue muy baja (4%) en comparacion con otras especies del mismo y distinto genero.
Revista De Biologia Tropical, 1994
Las lagartijas del genero Liolaemus , estan representadas por mas de 100 especies (Etheridge &... more Las lagartijas del genero Liolaemus , estan representadas por mas de 100 especies (Etheridge & Queiroz 1988), y poseen una amplia distribucion en Sudamerica, abarcando variedad de ambientes (Peters & Donoso-Barros, 1986). La mayoria de sus especies son insectivoras, aunque se ha discutido si consumen tambien materia vegetal, especialmente en ambientes pobres o fluctuantes.
Salta presenta superficies contaminadas con boro. Una técnica para descontaminar suelos es la fit... more Salta presenta superficies contaminadas con boro. Una técnica para descontaminar suelos es la fitorremediación. El primer paso es detectar plantas tolerantes, lo que constituye el objetivo de este trabajo. Se realizó un experimento en laboratorio para evaluar germinación, supervivencia y crecimiento de especies en diferentes concentraciones de boro. Se determinó la concentración de boro en sustrato y en tejido vegetal para cada tratamiento. Se encontraron diferencias significativas debidas al tratamiento, la especie y la interacción especie*tratamiento. Hubo una disminución en el porcentaje y velocidad de germinación, en los tratamientos de suelo Baradero mezclado con mantillo. En cambio la supervivencia fue mayor en el suelo Baradero mezclado con arena. La disminución de boro en sustrato fue máxima cuando fue mezclado con arena. En cambio en el tejido vegetal se detectó mayor contenido de boro cuando fue mezclado con mantillo, siendo superior en L. multiflorum. Se concluye que son ...
Revista De Biologia Tropical, 2016
Las lagartijas del genero Liolaemus , estan representadas por mas de 100 especies (Etheridge & Qu... more Las lagartijas del genero Liolaemus , estan representadas por mas de 100 especies (Etheridge & Queiroz 1988), y poseen una amplia distribucion en Sudamerica, abarcando variedad de ambientes (Peters & Donoso-Barros, 1986). La mayoria de sus especies son insectivoras, aunque se ha discutido si consumen tambien materia vegetal, especialmente en ambientes pobres o fluctuantes.
Revista De Biologia Tropical, 2016
Abundance, distribution and species association of Trichocereus pasacana were studied at Los Card... more Abundance, distribution and species association of Trichocereus pasacana were studied at Los Cardones National Park Salta, Argentina. 3200 ha were sampled using areal methods. Mean density was 34,33 individuals ha. Two distinctive groups were found: one of higher density including number of renewals, and the other of lower density and absence of renewals. Altitude was negatively related to density. Adults distribute randomly, while renewals are found agregated. 20% of individual s were associated to Larrea divaricata and 37% with L. divaricata, Bougainvillea sp., Baccharis spp. and Prosopis ferox . Only II % was not associated
Revista De Biologia Tropical, 2016
En una area de 150 ha en el Valle de Tin Tin, provincia de Salta, Argentina, se estudio la densid... more En una area de 150 ha en el Valle de Tin Tin, provincia de Salta, Argentina, se estudio la densidad, estructura de la poblacion, proporcion sexual, frecuencia de colas regeneradas y periodo de actividad de la lagartija Liolaemus darwinii . La densidad fue maxima en mayo de 1989 (41 individuos/ha) y minima en abril de 1990 (4 individuos/ha). Los infantiles se reclutan en otono, constituyendo el 49 % (mayo 1989), el 75% (abril 1990) y el 66% (mayo 1990) de la poblacion. Los juveniles, ausentes en abril, comienzan a incorporarse a partir de los infantiles en mayo. La densidad de los adultos es baja todo el ano y en verano su proporcion es maxima (42%). La proporcion sexual fue 1: 1 en todas las estaciones del ano. Su periodo diario de actividad es maximo en las horas del medio dia. Parece existir una preferencia de L. darwini por L. divaricata , una planta cuya morfologia y distribucion le proporcionan un refugio mas adecuado y una mayor disponibilidad de alimento por unidad de espacio...
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Papers by Marta Leonor de Viana