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La diversidad de perspectivas con que puede contemplarse el suelo, no deben ocultar su dimensión principal y fundamental, es decir, su configuración como elemento del ambiente. No resulta posible explicar el funcionamiento del medio ambiente sin consideraLa diversidad de perspectivas con que puede contemplarse el suelo, no deben ocultar su dimensión principal y fundamental, es decir, su configuración como elemento del ambiente. No resulta posible explicar el funcionamiento del medio ambiente sin considerar la participación del suelo, como tampoco resulta posible organizar su protección al margen de la cabal consideración y tratamiento de tal elemento en el complejo ambiental.

Vacant urban land--the product of land market activity, the actions of private agents, and the policies of public agents--is an important challenge for policy makers. Vacant lots on the urban fringe and in central and interstitial areas have affected growth patterns in Latin America. Contributors to this book analyze the problems and opportunities related to vacant urban land in five cities: Buenos Aires, Argentina; Rio de Janeiro, Brazil; Quito, Ecuador; Lima, Perú; and San Salvador, El Salvador.

In recent times what has become known as "the case of Medellín " has generated a growing interest in the international community. These urban transformation that Medellín has experimented have become a focus of attention and reference for experts in many fields, around the world. The book ́Medellin: Environment, Urbanism and Society ́, that now published the Center for Urban and Environmental Studies, Urbam, of EAFIT University is a testimony of the value given by our culture to the accomplishments of the city, to the idea of the public sphere and the growing relationship between the technical sphere and the political sphere, understood in the broad sense as a form of disciplinary knowledge and construction of civil society. This book brings together a knowledge of the city from multiple perspectives; knowledge that is, without any doubt, impressive for its extension and profoundity, as well as for its capacity to combine objective data with conceptual reflections about the scope and impact of the different perspectives concerning the theme of urban transformation and the different actors that have participated in such processes. The book weaves a broad net over the city, its history and development, adopting a multidisciplinary vision. I think that this will be the first step in creating a speech that might finally liberate itself from the strict disciplinary boundaries, building a trans-disciplinary perspective that can amplify the urban dimension of the city. This is the beginning of a profound and complex reflection that is, at the same time, a project of knowledge and an instrument of action and participation.

The North American Mosaic has four overarching features. First, it is, to the extent feasible, based on comparable information on the status and trends of major indicators of the state of the environment in Canada,Mexico, and the United States. Second, the report confirms that these three countries together make up an incredibly complex, dynamic, and interconnected ecosystem in which humans play a dominant and decisive role. Third, the report raises important and sometimes disquieting questions concerning the sustainability of some current trends. Finally, the report is a reminder that our economic, social, and physical well-being are utterly dependent on the life-sustaining services provided by nature. This report emphasizes the importance of developing mutually compatible economic, social, and environmental goals and policies across the three-country region.

On October 14-19, 1990, the 6th International Conference on the Conservation of Earthen Architecture was held in Las Cruces, New Mexico. Sponsored by the GCI, the Museum of New Mexico State Monuments, ICCROM, CRATerre-EAG, and the National Park Service, under the aegis of US/ICOMOS, the event was organized to promote the exchange of ideas, techniques, and research findings on the conservation of earthen architecture. Presentations at the conference covered a diversity of subjects, including the historic traditions of earthen architecture, conservation and restoration, site preservation, studies in consolidation and seismic mitigation, and examinations of moisture problems, clay chemistry, and microstructures. In discussions that focused on the future, the application of modern technologies and materials to site conservation was urged, as was using scientific knowledge of existing structures in the creation of new, low-cost, earthen architecture housing.