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An amendment to this paper has been published and can be accessed via a link at the top of the paper.
RESUMO
This paper presents a digital elevation model (DEM) of the dunes found in the Lençóis Maranhenses National Park, an environmental protection area located in the Maranhão state (Brazil). The DEM supports the modeling studies of sand-dune evolution using multi-temporal satellite images and ground truth data, obtained through the post-processed kinematic Global Navigation Satellite System (GNSS) positioning. The study area is located at the border of three major neotropical ecosystems: the Amazonia, Caatinga, and Brazilian savanna. It is located in the northeastern state of Maranhão and encompasses the largest dune fields in the country. Wide shrubby areas (restingas, in Portuguese), lakes, mangroves, and a multitude off reshwater lagoons compose the park's natural environments. The objective of the present study is to create an DEM that can evidence the complex dynamics of dune formation in the study area with use of GNSS. Geodetic techniques and precision mapping were employed to monitor the short-term coastal dynamics. The use of GNSS receivers is justified by the difficulty of mapping the dune's features using conventional methods such as theodolite, level, and total station systems, due to their high cost, time restriction sand low data precision. Surface surveys were carried out annually between December 2015 and January 2017 to create a DEM. The study results reveal that the area has a negative volumetric balance of erosion and a preferential direction of sediment transport by wind, which may justify the pattern of advancement and retraction observed in the dunes of the studied area.
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Avaliou-se a ação fisiológica de triclorfom, triflumurom, endosulfam, fempropatrina, clorpirifós, tebufenozide e esfenvalerato em larvas de 2° ínstar de Chrysoperla externa (Hagen) e seus efeitos subseqüentes sobre o 3° ínstar, pupas e adultos. Os experimentos foram realizados em casa de vegetação, avaliando-se o efeito de contato dos inseticidas em larvas de 2° ínstar, mantidas em algodoeiros pulverizados, e o efeito sobre larvas nesse estádio que se alimentaram de ovos de Anagasta kuehniella (Zeller) tratados com inseticidas. Foi avaliada a sobrevivência dos indivíduos no 2° e 3° ínstares e na fase de pupa. Na fase adulta, verificou-se a produção diária e total de ovos durante 30 dias e a viabilidade e fertilidade dos ovos. Endosulfam, tebufenozide e esfenvalerato foram seletivos às larvas de 2° ínstar tanto por contato como pela sucção do conteúdo de ovos tratados. Para larvas de 3° ínstar, esses inseticidas não foram prejudiciais, assim como o triflumuron. A sobrevivência de pupas oriundas de larvas de 2° ínstar tratadas com fempropatrina e tebufenozide não foi afetada. Triclorfom, fempropatrina e tebufenozide não provocaram redução no número total de ovos produzidos pelas fêmeas provenientes de larvas alimentadas com ovos tratados. Esfenvalerato, por contato, não reduziu significativamente a produção total de ovos. Por se apresentar seletivo às larvas de 2° ínstar de C. externa, tebufenozide apresenta características favoráveis para uso em associação com liberações inundativas do predador para o controle de pragas na cultura do algodoeiro, embora tenha afetado sua capacidade reprodutiva.
The physiological action of the insecticides trichlorfon, triflumuron, endosulfan, fenpropathrin, chlorpiryfos, tebufenozide and esfenvalerate to 2nd-instar larvae of Chrysoperla externa (Hagen) and subsequent effects on 3rd-instar larvae, pupae and adults were evaluated. The bioassays were carried out under greenhouse conditions. The effect on larvae fed on eggs of Anagasta kuehniella (Zeller) treated with the insecticides was evaluated, as well as the contact effect on 2nd-instar larvae kept on sprayed cotton plants. The survival percentage of individuals in the second- and 3rd-instar and in the pupae stage was determined. For adults, the daily and total production of eggs during 30 days, the viability and the fertility of eggs were evaluated. Endosulfan, tebufenozide and esfenvalerate were selective to 2nd-instar larvae by contact on sprayed plants as well as by suction of treated eggs. For 3rd-instar larvae, neither endosulfan, tebufenozide, esfenvalerate nor triflumuron were harmful. The survival of pupae from treated 2nd-instar larvae with fenpropathrin and tebufenozide was not affected. Trichlorfon, fenpropathrin and tebufenozide caused no reduction in the total number of eggs produced by females derived from 2nd-instar larvae fed with treated eggs of A. kuehniella. Females originated from larvae that kept contact with sprayed cotton plants with esfenvalerate, had no significant reduction in the total egg production. Although tebufenozide affected the reproductive traits of C. externa, it can be recommended for controlling the pests on cotton crop in association with inundative releases of this predator.