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The definition of limits of any geographic unit, based in the physiography of the landscape, is useful at the moment of developing environmental management politics and guidelines. Several authors have divided the Argentine Republic into regions according to the characteristics of native vegetation. The resulting units are known as phytogeographic provinces. The Monte Phytogeography Province is one of the largest ecoregions of the country and is defined as a unit where the environmental aspects are complex and difficult to categorize. In the present paper, a review of the limits of this phytogeographic province is made, according to bibliographic records of different authors. Survey trips were made and the collected data was georeferenced. A geographic information system was created with geodata and through records analysis, field work and adopting several criteria for its evaluation; the adjusted limits for the ecoregion were adjusted. A new map of the Monte Phytogeography Province is proposed for its use as input in the application of politics in the territory. [ABSTRACT FROM AUTHOR]

Spatial distribution of alien trees was studied on Pre-Delta National Park (PNPD-Entre Ríos, Argentina), by distance sampling techniques. Potential distribution was modelled by Kriging interpolation technique. Generated maps were overlapped with PNPD zonification map and environmental units map. We recorded forest structural data, tree phenology and tree control management actions, in order to characterize the processes of invasion. We obtained maps of potential distribution of Melia azedrach, Broussonetia papyrifera, Ligustrum lucidum, Brachychiton populneus, Fraxinus sp. and Morus alba L. The latter was the dominant species in all studied sectors (cliffs, islands and highlands). As for the management actions carried out with trees of the PNPD, about 50% of the specimens of M. alba subjected to mechanical control (banding technique) showed regrowth, indicating its high survival capacity. [ABSTRACT FROM AUTHOR]

Se presenta una descripción fitogeográfica de la provincia de Mendoza, enfocada en la distribución de licofitas y helechos. Se indica la clasificación botánica y se describe la distribución de familias incluyendo Aspleniaceae, Thelypteridaceae y Woodsiaceae, en la diversidad geomórfológica de Mendoza.

The rangeland carrying capacity of four fields (about 117,000 ha), located in the Malargüe department, Mendoza was estimated. These areas were included in "La Payunia" phytogeographic province. A floristic unit map was made through the interpretation of the area satellite image. An inventory of plant species was made in each unit and also the grazing degree was visually estimated. Linear transects (358) were distributed at random in the floristic units. The total plant and forage plant cover (%) and the carrying capacity were determined in each floristic unit. These determinations were made in different seasons during 2006 and 2007. The Field I had the greater number of forage species (19 to 30). It could sustain 9,203 goat equivalents (GE) or 1,538 cow equivalents (CE) in spring. In the Field II the number of forage species varied from 7 to 17. It presented the greater percentage of overgrazing area (38%). It could sustain 385 GE or 64 CE and 709 GE or 118 CE in winter and spring, respectively. The Field III had from 14 to 19 forage species. Only the 18% of its area was overgrazing. It could sustain as a minimum (winter) 10,206 GE or 1,715 CE. The Field IV presented the lower number of forage species (7 to 16). It could sustain 2,963 GE or 489 CE. For obtaining more accurate information on the carrying capacity, the evaluations should be made at least during one vegetative cycle (fall-winter and spring-summer). The characteristics of the floristic units of each field and the study of the herbivore diet composition carried out in the study area permitted to recommend the livestock species more adequate for the field use. [ABSTRACT FROM AUTHOR]

First citation of Lycopsis arvensis L. (Boraginaceae) for the province of Buenos Aires. [ABSTRACT FROM AUTHOR]

Torilis arvensis (Huds.) Link has been collected in the northeast of Buenos Aires province, Argentina, in urban areas, confirming its existence in the country as was predicted by Pedersen's contribution to the Flora Ilustrada de Entre Rios. This is a rare species in the United Kingdom, but classified as harmful plant in Spain and as a weed in several states of the United States of America. In our country, is regarded as an introduced naturalized plant, which may behave like invasive (plant strategist R) because, among other features, it is a therophyte producing abundant viable seeds. The present paper describes and illustrates this species, including the pollen grains which were studied using optical and scanning electron microscopy. [ABSTRACT FROM AUTHOR]

Se presenta un inventario parcial de la flora y la vegetación de las zonas urbanas de la región centro-oeste de Argentina. Se describen las características de cada especie de plantas, citando sus rasgos botánicos, su familia y género y su distribución geográfica en la provincia. Entre las especies se encuentran Fraxinus L., Syringa L. y Osmanthus Lour.

Se presenta un inventario parcial de la flora y la vegetación de la provincia de Mendoza, Argentina. Se describen las características de cada especie de plantas, citando sus rasgos botánicos, su familia y género y su distribución geográfica en la provincia. Entre las especies se encuentran Pantacantha, Schizanthus y Reyesia.