944 resultados para Spoil banks.


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El estudio se realizó en el municipio Tisma, Masaya en la finca “El Cha güit e” en los meses de Septiembre a Noviembre del 2014 , con el objetivo de estudiar el efecto de dos sistemas de siembra , monocultivo y policultivo, sobre la o currencia poblacional de artrópodos plagas y benéficos y severidad del ataque de l á caro blanco en el cultivo de c hiltoma . Para el desarrollo de la investigación se estableciero n cuatro parcelas, una con el arreglo en poli cultivos de chiltoma, maíz, tomate , y uca y quequisque; y los restantes se establecieron con monocultivo de chiltom a, maíz y tomate . Las variab les evaluadas semanalmente fuero n la o currencia poblacional de artrópodos plagas y benéficos , o currencia y se veridad del ácaro blanco y el rendimiento obteni do en los cultivos de chiltoma, maíz y tomate para el análisis del uso equivalente de la tierra ( LER ) . Los datos obtenidos se analizaro n a través de medias, error estándar de la media, análisis de varianza y separación de medias por Tukey a un nivel de con fianza del 95%, utilizando el programa InfoStat versión 2015 . El sistema de siembra policultivo presentó menor o currencia de plagas (0.95 individuos por planta) , menor densi d ad poblacional de ácaro blanco (1.77 individuos por planta) , menor severi dad en el ataque de ácaro blanco (74.33%) , mayor densidad poblacional de artrópodos benéfico s (0.06 individuos por planta) y un mejor aprovechamient o de la tierra por unidad de área

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The Flower Garden Banks are topographic features on the edge of the continental shelf in the northwest Gulf of Mexico. These banks are approximately 175 km southeast of Galveston, Texas at 28° north latitude and support the northernmost coral reefs on the North American continental shelf. The East and West Flower Garden Banks (EFG and WFG) and Stetson Bank, a smaller sandstone bank approximately 110 km offshore, are managed and protected as the Flower Garden Banks National Marine Sanctuary (FGBNMS). As part of a region-wide initiative to assess coral reef condition, the benthic and fish communities of the EFG and WFG were assessed using the Atlantic and Gulf Rapid Reef Assessment (AGRRA) protocol. The AGRRA survey was conducted during a week-long cruise in August 1999 that was jointly sponsored by the FGBNMS and the Reef Environmental Education Foundation (REEF). A total of 25 coral transects, 132 algal quadrats, 24 fish transects, and 26 Roving Diver (REEF) surveys were conducted. These surveys revealed reefs with high coral cover, dominated by large, healthy corals, little macroalgae, and healthy fish populations. The percent live coral cover was 53.9 and 48.8 at the WFG and EFG, respectively, and the average colony diameter was 93 and 81 cm. Fish diversity was lower than most Caribbean reefs, but large abundances and size of many species reflected the low fishing pressure on the banks. The benthic and fish assemblages at the EFG and WFG were similar. Due to its near pristine conditions, the FGB data will prove to be a valuable component in the AGRRA database and its resulting scale of reef condition for the region. (PDF contains 22 pages.)

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Submersible surveys at numerous reefs and banks in the northwestern Gulf of Mexico (NWGOM) were conducted as part of the Sustainable Seas Expedition (SSE) during July/August 2002 to identify reef fish communities, characterize benthic habitats, and identify deep coral reef ecosystems. To identify the spatial extent of hard bottom reef communities, the Flower Garden Banks National Marine Sanctuary (FGBNMS) and the U.S. Geological Survey (USGS) mapped approximately 2000 km2 of the Northwestern Gulf of Mexico (NWGOM) continental shelf during June 2002 with high-resolution multibeam bathymetry. Previous investigations conducted on the features of interest (with the exceptions of East and West Flower Garden and Sonnier Banks, accessible by SCUBA) had not been conducted since the 1970s and 1980s, and did not have the use of high-resolution maps to target survey sites. The base maps were instrumental in navigating submersibles to specific features at each study site during the Sustainable Seas Expedition (SSE)—a submersible effort culminating from a partnership between the National Atmospheric and Oceanic Administration (NOAA) and the National Geographic Society (NGS). We report the initial findings of our submersible surveys, including habitat and reef fish diversity at McGrail, Alderdice, and Sonnier Banks. A total of 120 species and 40,724 individuals were identified from video surveys at the three banks. Planktivorous fishes constituted over 87% by number for the three banks, ranging from 81.4% at Sonnier Banks to 94.3% at Alderdice Bank, indicating a direct link to pelagic prey communities, particularly in the deep reef zones. High numbers of groupers, snappers, jacks, and other fishery species were observed on all three features. These sites were nominated as Habitat Areas of Particular Concern (HAPC) by the Gulf of Mexico Fishery Council in March 2004. Data obtained during this project will contribute to benthic habitat characterization and assessment of the associated fish communities through future SCUBA, ROV, and submersible missions, and allow comparisons to other deep reef ecosystems found throughout the Gulf of Mexico and western Atlantic Ocean.

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The aim of this work is to analyze the main characteristics of the current financial system and to investigate the arising of critical voices with respect this system. In particular, we analyze some historical facts that have been important in the creation of this financial order. We analyze the new digital currency, known as Bitcoin, as the basic ingredient in the formation of a new alternative and decentralized international financial system. In 10 years Bitcoin has expanded its influence to many economic activities. We also analyzed briefly the classic liberal theory that criticizes the intervention of governments in the markets. Finally, we consider relevant the arising of a group of countries (BRICS) that may challenge the current system where the position of USA is privileged.

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There is increasing interest in the potential impacts that fishing activities have on megafaunal benthic invertebrates occurring in continental shelf and slope ecosystems. We examined how the structure, size, and high-density aggregations of invertebrates provided structural relief for fishes in continental shelf and slope ecosystems off southern California. We made 112 dives in a submersible at 32−320 m water depth, surveying a variety of habitats from high-relief rock to flat sand and mud. Using quantitative video transect methods, we made 12,360 observations of 15 structure-form-ing invertebrate taxa and 521,898 individuals. We estimated size and incidence of epizoic animals on 9105 sponges, black corals, and gorgonians. Size variation among structure-form-ing invertebrates was significant and 90% of the individuals were <0.5 m high. Less than 1% of the observations of organisms actually sheltering in or located on invertebrates involved fishes. From the analysis of spatial associations between fishes and large invertebrates, six of 108 fish species were found more often adjacent to invertebrate colonies than the number of fish predicted by the fish-density data from transects. This finding indicates that there may be spatial associations that do not necessarily include physical contact with the sponges and corals. However, the median distances between these six fish species and the invertebrates were not particularly small (1.0−5.5 m). Thus, it is likely that these fishes and invertebrates are present together in the same habitats but that there is not necessarily a functional relationship between these groups of organisms. Regardless of their associations with fishes, these invertebrates provide structure and diversity for continental shelf ecosystems off southern California and certainly deserve the attention of scientists undertaking future conservation efforts.

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In the last decades the creation of new Environmental Specimen Banks (ESB) is increasing due to the necessity of knowing the effects of pollutants in both the environment and human populations. ESBs analyze and store samples in order to understand the effects of chemicals, emerging substances and the environmental changes in biota. For a correct analysis of the effect induced by these variables, there is a need to add biological endpoints, such as biomarkers, to the endpoints based on chemical approaches which have being used until now. It is essential to adapt ESB´s sampling strategies in order to enable scientists to apply new biological methods. The present study was performed to obtain biochemical endpoints from samples stored in the BBEBB (Biscay Bay Environmental Biospecimen Bank) of the Marine Station of Plentzia (PIE - UPV/EHU). The main objective of the present work was to study the variability caused in biochemical biomarkers by different processing methods in mussels (Mytilus galloprovincialis) from two localities (Plentzia and Arriluze) with different pollution history. It can be concluded that the selected biomarkers (glutathione S-transferase and acetylcholinesterase) can be accurately measured in samples stored for years in the ESBs. The results also allowed the discrimination of both sampling sites. However, in a further step, the threshold levels and baseline values should be characterized for a correct interpretation of the results in relation to the assessment of the ecosystem health status.

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The crab (swimming crab; Portunus pelagicus) fishery in coastal Cambodia appears to have declined in recent years due to over-fishing and a growth in the number of fishermen, but remains an important source of income for households along the coast. Several initiatives have started since 2007, with support from NGOs, international organizations and the Fisheries Administration (FiA), to test stock enhancement techniques through the release of crab larvae. The so-called “crab bank” initiative involves keeping harvested gravid crabs alive in cages for a few days until they spawn, instead of immediately selling them for consumption or processing. In Cambodia, this initiative has developed within the framework of Community Fisheries (CFis) and thus implies a communitybased approach. The FiA has promoted the continuation of such initiatives; however, the nature of crab fisheries and the results from crab bank initiatives have not been documented in detail. The scope of this study was to understand the diversity of approaches to crab bank development in Cambodia, as well as their operational status and the challenges faced at differen