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A large amount of dust from the Sahara reaches the Amazon Basin, as observed with satellite imagery. This dust is thought to carry micronutrients that could help fertilize the rainforest. However, considering different atmospheric transport conditions, different aridity levels in South America and Africa and active volcanism, it is not clear if the same pathways for dust have occurred throughout the Holocene. Here we present analyses of Sr-Nd isotopic ratios of a lacustrine sediment core from remote Lake Pata in the Amazon region that encompasses the past 7,500 years before present, and compare these ratios to dust signatures from a variety of sources. We find that dust reaching the western Amazon region during the study period had diverse origins, including the Andean region and northern and southern Africa. We suggest that the Sahara Desert was not the dominant source of dust throughout the vast Amazon basin over the past 7,500 years.

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The eastern continental margin of India is aligned NE-SW due to the trend of the Eastern Ghat orographic belt in the northern part and almost north-south in the southern part. It is of passive type, the origin of which can be traced back to its separation from Antarctica around 127 Ma ago. The 2493 km-long shoreline of eastern India is fringed with a continental shelf with a variable width of 35 km off Tamil Nadu to 60 km off north Andhra Pradesh and 120 km around Digha. The shelf has a gentle slope in the northern sector and is moderately steep in the south. Net longshore sediment transport along the east coast is from south to north. The east continental shelf of India is characterized by four major deltas; the Ganges, Mahanadi, Krishna-Godavari and Cauvery. The interdeltaic shelves are generally sediment starved. The inner shelf is silty to clayey silt and sandy, whereas the outer shelf has carbonate sands with coral debris and shell fragments. The outer shelf is characterized by carbonate sands, lime mud and ooids in the north Andhra Pradesh sector off the Kakinada-Kalingapatnam sector. The outer shelf off Chennai-Mahabalipuram, Nagapattinam -Point Calimere is characterized by a thin veneer of authigenic sediment represented by verdine, glaucony and phosphatic sediment. In Tamil Nadu, the region between 108N and 12830 0 N is characterized by two megalineaments and associated tectonics, suggesting that the area is tectonically active.The 14 C dating of relict corals, from water depths of 120 m, off Karaikal indicates an age of 18 390 + 210 years BP, establishing the low sea-level position of the Last Glacial Maximum. The large volume of sediment input from the deltaic system of two major drainages, Krishna and Godavari, has a significant influence on the morphology and sedimentation of the continental shelf. The influence of glacioeustasy is noticeable in outer shelf sediments along almost the entire length of the shelf. † Deceased

Forest fires are one of the main disasters that devastate many countries every year. The destruction caused by these phenomena generates social impacts putting at risk the population lives, environmental impacts due to the extreme deforestation and the high number of pollutants that are released to the atmosphere but also extremely important economic impacts caused by the destruction of a wide range of infrastructures and essential goods. Therefore, as it is impossible to remove all the infrastructures from the forest and from the wildland-urban interface, the development and installation of protection systems is essential. The main objective of this work is the development of a low cost protection system, with rigid panels, requiring a simple and easy installation, to protect outdoor infrastructures such as telecommunications stations, shelters, roadside enclosures, power cabinets, and other structures. A study was carried out on panels that could be used for the protection in order to determine whether the protective material would be more appropriate. Taking into account the fire resistance behaviour, thermal and structural properties and cost, the panels selected were the magnesium oxide fibreglass reinforced. The protection was constructed, installed on a telecommunication cabinet and experimentally laboratory tested in a wind combustion tunnel. To collect the data InfraRed and video cameras, heat flux sensors and sheathed thermocouples were used to determine the fire propagation, heat flux and temperatures, respectively. The data obtained in the experimental tests show clearly that the simple low cost protection is effective for the protection of telecommunication cabinets and other similar infrastructures against forest fires.