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131.
Several gateways connected the Mediterranean with the Atlantic during the late Miocene but the timing of closure and therefore their role prior to and during the Messinian Salinity Crisis (5.97–5.33 Ma) is still under debate. The timing of closure of the Guadalhorce Corridor is especially disputed as the common lack of marine microfossils hampers precise age determination. Here we present new biostratigraphic age constraints on the sediments of the Ronda, Antequera and Arcos regions, which formed the northern part of the Guadalhorce Corridor. The general presence of Globorotalia menardii 4 in the youngest deep‐marine sediments of all three regions indicates a late Tortonian age, older than 7.51 Ma. We conclude that the Guadalhorce Corridor closed during the late Tortonian, well before the onset of the Messinian Salinity Crisis and that the late Tortonian tectonic uplift of the eastern Betics extended into the western Betics.  相似文献   
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Abstract

Given the linkages between natural resources and social conflicts, evidence increasingly shows that successful natural resource management requires conflict mitigation and prevention. However, there may be a gap in practice between knowing what processes and tools need to be used to manage conservation conflicts and how to actually implement them. We present learning from a practice-based case study of conflict management in the Amarakaeri Communal Reserve in the Peruvian Amazon that aimed to develop natural resource governance institutions and build stakeholder capacity, including of indigenous groups, to navigate existing conflict resolution mechanisms. Through applying good practices in conservation conflict management and collaborative governance, we generated important lessons on the practical considerations involved in collaborative conservation. These lessons, while specific to our case, could be applied to a variety of protected areas facing complex social-ecological systems dynamics and wicked problems.  相似文献   
133.
This paper investigates the complex demographic and social changes that have occurred in the neighborhoods of fast-growing United States metropolitan areas emerging as nodes in megapolitan regions between 1980 and 2010. A neighborhood typology is created using k-means cluster analysis to examine the demographic and housing characteristics, and geographic distribution, of neighborhoods that have existed in rapidly growing metropolitan areas. A socioeconomic index is created using principal component analysis (PCA) to analyze socioeconomic conditions within neighborhoods. Using data from the metropolitan areas of Las Vegas, Nevada; Austin, Texas; and Raleigh, North Carolina, this study identifies five neighborhood types, each of which has distinctive geographic and socioeconomic trends. The geographic orientation of each metropolitan area within their larger megapolitan region appears to have a role in the geography of neighborhood change. The results are also discussed in relation to human ecology, immigration, and economic restructuring.  相似文献   
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In memoriam     
Ohne Zusammenfassung  相似文献   
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If in imagination we viewed a solar eclipse or the occultation of a star from a point outside the earth, we would see the shadow of the moon advancing across the face of the earth, the earth meanwhile turning on its axis beneath the shadow. When some point on the advancing edge of the shadow overtook a given point on the surface of the earth, an observer at that point would note the beginning of the eclipse or occultation. When the trailing edge of the shadow uncovered that point again, the observer there would note the end of the eclipse or occultation. The universal time (as distinguished from the local time) of the beginning or ending would depend on the position of the observer with reference to the body of the earth, that is, on his ideal geodetic coordinates. These universal times would not depend in the least on the direction of the observer’s vertical. This fact is the key to the usefulness of eclipses and occultations for geodetic purposes. Suppose that the prediction for the times of beginning or ending had been made on the basis of the astronomical latitude and longitude of the observer. Since there would be in general deflections of the vertical in latitude and longitude, Δπ and Δλ, these would bring about, even in the absence of any other source of discrepancy, diffe- This article is at once a condensation and an expansion. It is a condensation of a series of lectures delivered in the winter and spring of 1947 to members of the U. S. Coast and Geodetic Survey and of the Army Map Service. It is an expansion of a very informal lecture given before Section III of the International Association of Geodesy, meeting in General Assembly at Oslo in August, 1948.  相似文献   
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Ohne Zusammenfassung  相似文献   
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