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Santiago, Chile

Bird monitoring is frequent in wetlands; however, in the absence of information on other variables, trends in bird numbers are difficult to interpret. In this article we describe a methodology for bird's habitat area assessment based on remote sensing. We calibrated the methodology to study the changes in the habitat area of Cygnus melancoryphus, the black-necked swan, at the Carlos Anwandter Sanctuary, a wetland located in Valdivia, Southern Chile. Swan habitat area was estimated by means of the Normalized Difference Vegetation Index (NDVI) based on Landsat images and calibrated through spectral photography by means of a portable Tetracam ADC Camera. Results show that calibrated NDVI values from Landsat images can be used to estimate habitat area but not to separate individual species of vegetation. We also show that the joint analysis of habitat area and swan count can indeed be used to separate some of the scales of variability of bird counts: those with "local-influence" associated with changes in habitat area from those of larger scales not related with habitat area. © 2012 Society of Wetland Scientists. Source

Delgado L.E.,Fundacion CTF | Tironi A.,Fundacion CTF | Vila I.,University of Chile | Verardi G.,University of Santiago de Chile | And 3 more authors.
Latin American Journal of Aquatic Research | Year: 2014

We review in this article the 2004-2014 scientific information on the Río Cruces wetland ecosystem, Valdivia, Chile. This information is used in the generation of a conceptual ecosystem model, which is used in turn to generate a synthetic hypothesis about the regime shift during 2004/2005. The model is based on the concentration of suspended solids in the wetland as controlling variable, affected by watershed processes (e.g., clear-cut forestry) and re-suspension of sediments in the wetland affected by the presence or absence of macrophytes. © 2014, Escuela de Ciencias del Mar. All rights reserved. Source

Delgado L.E.,Fundacion CTF | Delgado L.E.,University of Chile | Marin V.H.,University of Chile
Ecosystem Services | Year: 2015

The analysis of temporal changes in the number of scientific articles written on ecosystem services shows an exponential growth from 1991 to 2013. However, it also shows a lack of information regarding the location of the studies and the type of ecosystem analyzed. A literature search showed that some regions (Antarctica) and ecosystems (urban) have been less studied. However, given the structure of the knowledge databases it is impossible to know if there are no studies or it is difficult to reach them. © 2015 Elsevier B.V. Source

Delgado L.E.,Fundacion CTF | Delgado L.E.,University of Chile | Sepulveda M.B.,University of Chile | Marin V.H.,University of Chile
Ecosystem Services | Year: 2013

How much do ecosystems contribute to the wellbeing of rural populations in developing nations? In this article we provide an answer to this question through an eco-social study of two provisioning ecosystem services (wood from native forest and clean water) of the Aysén watershed in northern Chilean Patagonia. Social data was gathered by means of a semi-structured survey to rural households while ecological data was obtained from the available literature and Chilean Government databases. Results show that provisioning ecosystem services contribute, on average, 148. USD per month (range: 155-345. USD) to the livelihood of rural households. We discuss the potential effect of rural wood exploitation on native forest coverage and the role of uncertainties in the available information. © 2013 Elsevier B.V. Source

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