No abstract

Coastal zones are very dynamic and fragile environments, constituting a landscape ever more heterogeneous, fragmented and with increasing levels of complexity due to the changing relationship between man and nature. Integrated coastal zone management therefore requires detailed knowledge of the system and its components, based-to a large extent-on technical and scientific information. However, the information generated must be in line with the political requirements necessary for decision-making and planning. Thus the use of indicators to give a simplified view of the many components of the territory, and at the same time to provide important information about patterns or trends, becomes a tool of the utmost importance. These indicators can be understood as measurable characteristics of the environment, which facilitate comprehension of the processes occurring at different scales and serve as a reference to inform the population and support decision-making. The aim of the present note is to demonstrate briefly the need to develop geographical-environmental and natural risk indicators to facilitate comprehension of the dynamic of spatial and temporal landscape patterns, particularly in coastal environments. This approach offers an historical summary of the natural, socio-economic and political processes which currently make up the territory, and which without doubt will continue to influence it in the future. At the same time, it is proposed that information should be integrated on the basis of this framework with a view to generating spatial decision support systems in a context of planning and integrated management of the coastal zones of Chile.

Se evaluó la dinámica de los campos dunarios del borde costero de La Araucanía entre los años 1994 y 2004, usando para ello la clasificación morfológica y grado de estabilización, evaluado a partir de material cartográfico, fotografías aéreas y reconocimiento en terreno. Se delimitaron 8 campos de dunas distribuidos en una superficie de 4.597 ha, constatándose una expansión total de 314 ha en el periodo; las dunas activas representaron un 35% de esta superficie, mientras que las dunas semiestabilizadas y estabilizadas representaron un 31 y 15% respectivamente. La morfología más frecuente fue el tipo de duna transversal y las especies vegetales con mayor frecuencia fueron Pinus radiata y Ammophila arenaria. Finalmente, la localización y la determinación de los grados de estabilización y formas dunarias permiten reconocer la acción de factores naturales y antrópicos, los que requieren ser abordados integralmente como base para una gestión integrada de esta zona costera.

In order to support Strategic Environmental Assessment of spatial plans, different scenarios were developed for the future configuration of wetlands along the coast of La Araucan ıa Region for 2020. To assess each scenario, landscape metrics related to landscape dynamics and structure were used. The results indicate that in general terms the wetland cover diminished and fragmented under different scenarios, including one which was designed for the sustainability of natural areas. It is concluded that the techniques used were relatively easy to implement by means of GIS technologies, which facilitate spatially explicit modelling of future scenarios. Furthermore, landscape metrics were a key element for assessing the effects of each model. There are currently only few experiences on the use of spatially explicit scenarios in SEA and our research suggests that this may be a useful and valid tool for supporting spatial planning decisions.

En esta investigación, se evidencian las implicancias ambientales de los procesos de transformación del paisaje sobre el territorio del borde costero de La Araucanía en Chile, el cual se caracteriza por cinco aspectos: (1) altos niveles de pobreza y de ruralidad, (2) una importante consolidación y expansión de asentamientos agregados, (3) presencia de elementos singulares dados por condiciones naturales (humedales, bosques pantanosos, estuarios), (4) pueblos originarios (mapuche) y (5) procesos de colonización tardía. La investigación muestra inicialmente una revisión exploratoria de los hitos históricos más relevantes que han determinado los procesos de transformación del paisaje. Luego se evalúa geoespacialmente el cambio de uso del suelo entre los años 1980 y 2004, lo que permite precisar las principales categorías de cambio del uso del suelo y el estado actual del paisaje ecológico. Este análisis se complementó con la revisión de indicadores demográficos y socioeconómicos que permite visualizar los efectos del cambio de uso del suelo en la población. Los resultados mostraron que la irrupción de la agroganadería hispano-mediterránea y la posterior desforestación por parte de los colonos tuvo graves efectos en el paisaje. Más recientemente, la dinámica de transformación en la matriz agropecuaria dominante hacia la actividad forestal (pasando de 1% en 1980 a 19% en 2004), ocasionó un retroceso de 8.762 ha de la matriz agropecuaria y una disminución general de todas las coberturas naturales. De este modo, se cuantificó una redistribución de los usos del suelo, aumento de la fragmentación del paisaje y pérdida de conectividad espacial de los sistemas naturales. A su vez, se constató un desplazamiento de la población rural y la consolidación de centros urbanos como Nueva Toltén, Hualpín, Teodoro Schmidt y Saavedra, lo cual se relaciona con la disminución de la natalidad, el incremento de la tasa de envejecimiento y la falta de empleo. Se concluye que la interfaz de relaciones socio-culturales, físico-ambientales y económicas en el área, dan cuenta de la necesidad de nuevos enfoques e instrumentos de planificación que permitan potenciar el desarrollo local. This research makes evident the environmental implications of the process of transforming the landscape in the territory of the coastal strip of La Araucania in Chile, which is characterized by five aspects: (1) high level of poverty and rurality, (2) a major consolidation and expansion of aggregate settlements, (3) the presence of singular elements due to natural conditions (wetlands, swamp forests, estuaries), (4) aboriginal people (mapuche) and, (5) late colonization process. The research shows initially an exploratory revision of the more relevant historical milestones, which have determined the process of transforming the landscape. Then, the change in land use between 1980 and 2004 it is geospatial rated, which allows to specify the main categories of change in land use and the current status of the ecological landscape. This analysis was complemented with the revision of demographic and socioeconomic indicators which permits to view the effects of the change in land use in the population. The results showed that the irruption of the spanish agriculture and and the subsequent deforestation by the settlers had severe effects on the landscape. More recently, the dynamics of transformation in the matrix to the dominant agricultural towards forestry (from 1% in 1980 to 19% in 2004), caused a decrease of 8.762 hectares of the agricultural matrix and a general decline of all natural coverage. Thus, a redistribution of the land use, an increased fragmentation of the landscape and a loss of spatial connectivity of natural systems was quantified. Besides, there was a movement of the rural population and a consolidation of urban centers like Nueva Toltén, Hualpin, Teodoro Schmidt y Saavedra, which it is related to falling of birth rate, increasing of rate of aging and lack of employment. We conclude that the interface of socio-cultural relations, economic and physical environment in the area, reveals the need for new approaches and planning tools for enhancing local development.