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The discussion on producing urban peripheries in Chile has focused on the capital. An understanding of this process is proposed for San Pedro de la Paz, a city in the Metropolitan Area of Concepción in the country's south. The hypothesis is that housing policy has been the most relevant actor in producing peripheral urbanisms. It is a territory where center-periphery relations are hybrid and strongly influenced by the relationship built with the landscape and nature. The methodology combined geographical analysis of land cover and use, documentary and normative analysis, and observation of different social housing complexes built at different times. The results show how the territory has historically been shaped as a peripheral and suburban area, which is consolidated by the action of the State, producing a diffuse space dominated by the values promoted by the middle classes. [ABSTRACT FROM AUTHOR]

The explanation of the origin of microbialites and specifically stromatolitic structures is a problem of high relevance for decoding past sedimentary environments and deciphering the biogenicity of the oldest plausible remnants of life. We have investigated the morphogenesis of gypsum stromatolite-like structures currently growing in shallow ponds (puquíos) in the Salar de Llamara (Atacama Desert, Northern Chile). The crystal size, aspect ratio, and orientation distributions of gypsum crystals within the structures have been quantified and show indications for episodic nucleation and competitive growth of millimetric to centimetric selenite crystals into a radial, branched, and loosely cemented aggregate. The morphogenetical process is explained by the existence of a stable vertical salinity gradient in the ponds. Due to the non-linear dependency of gypsum solubility as a function of sodium chloride concentration, the salinity gradient produces undersaturated solutions, which dissolve gypsum crystals. This dissolution happens at a certain depth, narrowing the lower part of the structures, and producing their stromatolite-like morphology. We have tested this novel mechanism experimentally, simulating the effective dissolution of gypsum crystals in stratified ponds, thus providing a purely abiotic mechanism for these stromatolite-like structures. [ABSTRACT FROM AUTHOR]

The objective of the research described here was to examine the policies, regulations, and instruments that directly or indirectly affect the coastal zones of the island and the sea of Chiloé (CZISC) and to evaluate the adequacy of the current political-administrative system concerning climate change. For this purpose, the Decalogue for Integrated Coastal Zone Management (ICZM) has been used as a methodological basis. Likewise, all policies, regulations, and instruments that have an impact on coastal management in Chiloé have been identified and classified based on their adaptation to problems that result from climate change. The documents have been grouped into seven numerical categories (1−7) that range from tools that omit the discourse on climate change (1) to those that focus exclusively on this subject and provide detailed information on the required actions and provisions (7). The lowest level (1) of the classification is predominant in the policies, regulations, and instruments studied, especially those that deal with subnational planning. Based on the strategic diagnosis presented, it was concluded that the lack of a holistic approach and the absence of discourse on climate change observed in Chiloé prevent the transition towards an ICZM model capable of improving human welfare and protecting socio-ecological systems in the long term. • Chilean policies, regulations and instruments are very unspecific in addressing the consequences of climate change. • Chiloé, an archipelago vulnerable to climate change, has a political-administrative system far from the ICZM model. • The lack of political will in Chile prevents the renewal of an outdated policy that ignores climate change. • The salmon farming generates socio-ecological conflicts that have their origin in the biased perception of regulations. [ABSTRACT FROM AUTHOR]

Cephalopods have two main defence strategies: the first consists on reducing the odds of being detected by a predator, while the second focuses on avoiding capture. The aim of this study was to understand the basic behavioural aspects of the octopus Robsonella fontaniana in response to the potential predator Schroederichthys chilensis (catshark) in central Chile. Experiments were conducted under laboratory conditions in order to determine the effectiveness of camouflage against predators. The results show that crypsis and an increase in the inactivity period are strategies used by octopuses as protection and defence mechanisms against predators. [ABSTRACT FROM AUTHOR]