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Aim The assumedly anomalous occurrence of savannas and forest–savanna mosaics in the Gran Sabana – a neotropical region under a climate more suitable for tropical rain forests – has been attributed to a variety of historical, climatic, and anthropogenic factors. This paper describes a previously undocumented shift in vegetation and climate that occurred during the early Holocene, and evaluates its significance for the understanding of the origin of the Gran Sabana vegetation. Location A treeless savanna locality of the Gran Sabana (4°30′–6°45′ N and 60°34′–62°50′ W), in the Venezuelan Guayana of northern South America, at the headwaters of the Caroní river, one of the major tributaries of the Orinoco river. Methods Pollen and charcoal analysis of a previously dated peat section spanning from about the Pleistocene/Holocene boundary until the present. Results Mesothermic cloud forests dominated by Catostemma (Bombacaceae) occupied the site around the Pleistocene/Holocene boundary. During the early Holocene, a progressive but relatively rapid trend towards savanna vegetation occurred, and eventually the former cloud forests were replaced by a treeless savanna. Some time after the establishment of savannas, a marked increase in charcoal particles indicates the occurrence of the first local fires. Main conclusions The occurrence of cloud forests at the Pleistocene/Holocene boundary contradicts the historical hypothesis according to which the Gran Sabana is a relict of the hypothetical widespread savannas that have been assumed to have dominated the region during the last glaciation. The first local fires recorded in the Holocene were on savanna vegetation, which is against the hypothesis of fire as the triggering factor for the establishment of these savannas. Climate change, in the form of global warming and a persistently drier climate, emerges as the most probable cause for the forest–savanna turnover. [ABSTRACT FROM AUTHOR]

Yang, Z.; Chen, D.; Huang, D., and Yang, Y., 2019. Prediction of coastal evolution in Puerto Cabello, Venezuela. In: Guido-Aldana, P.A. and Mulahasan, S. (eds.), Advances in Water Resources and Exploration. Journal of Coastal Research, Special Issue No. 93, pp. 16–21. Coconut Creek (Florida), ISSN 0749-0208. Coasts vary in their composition and the physical processes that affect them. However, their nature and behavior have similarities. Presently, the majority of coasts worldwide are eroding. The rapidly increasing threat of global warming and the resulting rise in sea level can accelerate coastal erosion. The nearly 2 km coastline in the port city of Puerto Cabello in Venezuela, to the west of the island Goaigoaza, was taken as a case study. The long-term state of the beach was assessed by considering the credits and debits of sand that pass through the coastal system. In the study, the net longshore sediment transport rate in the west of the salient was westward and Qin < Qout, denoting that beach erosion will occur in this particular area. Through field investigations and theoretical analysis, it can be preliminarily concluded that the beaches in the study area are slightly eroded. However, a long-term study on the current profile is essential to arrive at a decisive conclusion. [ABSTRACT FROM AUTHOR]

Coasts vary in their composition and the physical processes that affect them. However, their nature and behavior have similarities. Presently, the majority of coasts worldwide are eroding. The rapidly increasing threat of global warming and the resulting rise in sea level can accelerate coastal erosion. The nearly 2 km coastline in the port city of Puerto Cabello in Venezuela, to the west of the island Goaigoaza, was taken as a case study. The long-term state of the beach was assessed by considering the credits and debits of sand that pass through the coastal system. In the study, the net longshore sediment transport rate in the west of the salient was westward and Qin < Qout, denoting that beach erosion will occur in this particular area. Through field investigations and theoretical analysis, it can be preliminarily concluded that the beaches in the study area are slightly eroded. However, a long-term study on the current profile is essential to arrive at a decisive conclusion. [ABSTRACT FROM AUTHOR]

Environmental degradation is causing global warming, which is of the utmost concern to both physical and social scientists. A number of potential determinants of environmental degradation are analysed in the literature. This study examines the role of government expenditure and financial development in environmental degradation in the context of the environmental Kuznets curve (EKC) hypothesis for the Venezuelan economy. Time series data have been analysed for this purpose. The long-term relationship between the variables in this study is established through a bounds test in the presence of an unknown structural break. The results of this study confirm the EKC hypothesis. It is found that energy use is harming the quality of the environment not only in the long run but also in the short run. This study finds a positive impact of government expenditure on environmental degradation, which indicates that the Venezuelan government is not taking its expenditure for a sustainable environment into account. Moreover, this study finds that financial development is hindering environmental degradation. This means that financial institutions in Venezuela can help to develop the concept of sustainable energy in the country and the Venezuelan government can reduce carbon emissions through financial development. [ABSTRACT FROM AUTHOR]

Yang, Z.; Chen, D.; Huang, D., and Yang, Y., 2019. Prediction of coastal evolution in Puerto Cabello, Venezuela. In: Guido-Aldana, P.A. and Mulahasan, S. (eds.), Advances in Water Resources and Exploration. Journal of Coastal Research, Special Issue No. 93, pp. 16–21. Coconut Creek (Florida), ISSN 0749-0208. Coasts vary in their composition and the physical processes that affect them. However, their nature and behavior have similarities. Presently, the majority of coasts worldwide are eroding. The rapidly increasing threat of global warming and the resulting rise in sea level can accelerate coastal erosion. The nearly 2 km coastline in the port city of Puerto Cabello in Venezuela, to the west of the island Goaigoaza, was taken as a case study. The long-term state of the beach was assessed by considering the credits and debits of sand that pass through the coastal system. In the study, the net longshore sediment transport rate in the west of the salient was westward and Qin < Qout, denoting that beach erosion will occur in this particular area. Through field investigations and theoretical analysis, it can be preliminarily concluded that the beaches in the study area are slightly eroded. However, a long-term study on the current profile is essential to arrive at a decisive conclusion. [ABSTRACT FROM AUTHOR]