Archive | Marine Mapping

Santa Elena

Posted on 06 February 2013 by Nazca admin

During the month of April in 2008, NAZCA’s dive team performed a biodiversity evaluation of the benthic rocky communities in the Puntilla Santa Elena zone using subtidal censuses in 15 different sites that represented the majority of species diversity in the area. The location of each immersion was recorded using a Global Positioning System (GPS).

During September, 2008, we performed a seafloor mapping analysis in the marine area of the “Faunal Production Reserve Puntilla Santa Elena.” Since this study was done before the formal declaration of the reserve and thus the boundaries were not yet defined, only 79% of the actual area of the marine zone was mapped.

 

 

MapsFor this project we used single beam sonar (Roxann Groundmaster GD-X) with a Furuno LS4100 echosounder (Roxann control box), a mounted acoustic transductor, a Magellan eXplorist XL global positioning system (GPS), and a “Deep Blue” marine video camera system by Ocean System/Splashcam.

The sampling transects were designed taking into account the following parameters:

  • The provisional limits of the marine protected area,
  • The 50m depth limit,
  • The priority locations determined by biological monitoring,
  • The basic ship speed of 6 knots, and
  • The daily work schedule (hours worked per day).

Once the equipment was installed on the boat, it was calibrated using the help of the “Deep Blue” video system.

maps

The information was processed using Surfer8 and ArcGis 8.3 geographic information systems. The data that showed a change of +/- 1.5 m in 1-second intervals were eliminated from the dataset. With the resulting information, we created a depth model using the “Kriging” interpolation model and a resulting bathymetries map of the zone.

Marine seafloors were evaluated using the interpolation information and the “Nearest Neighbor” method and by considering the information compiled by the biological monitoring.

Among others, the zone known as Low Radius (Vicioso and Aquapark, Location Mapping of Area and GPS points), that represents groups of small and medium-sized rocks, stood out following the analysis. In the Vicioso site, a large variety of gorgonians, corals, algae, and sessile invertebrates are present, as well as a high abundance of commercial fish species.

This information has served as a baseline dataset for the evaluation of current states of marine habitats and their associated marine organisms. It has also facilitated the production of marine reserve maps (bathymetry and seafloor types) that help in making short, medium, and long-term decisions.

More Information:
– MAP 1: Location of the proposed Marine Reserve and location of the GPS points (11,7 MB, pdf). Also available in the PUBLICATIONS section.
– MAP 2: Bathymetric map of the covered area (10,5 MB, pdf). Also available in the PUBLICATIONS section.
– MAP 3: Habitats of the rocky-sandy bottom of the covered area (7,5 MB, pdf). Also available in the PUBLICATIONS section.

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ESMERALDAS (Project ESMEMAR)

Posted on 06 February 2013 by Nazca admin

In 2006, the project “Feasibility study for the creation of a coastal marine reserve in the province of Esmeraldas” (ESMEMAR) was developed with the general objective of analyzing the current situation of the coastal marine/intertidal zone between the towns of Muisne and Esmeraldas. Previously there had been no efforts to compile cartographic information of this area for the goal of mapping ecosystems and habitats. Accordingly, one of the main objectives of the project was to establish digital maps that would permit this characterization of marine zones, as well as identifying and delineating the range of the principal species of the area. Based on this mapping information, we were able to infer information regarding threats and resource use in order to evaluate conservation states and the future possible success of various management and conservation schemes for the region. The results served as the database for the development of the conservation proposal for the Galera-San Francisco-Muisne marine coastal area, and finally, the declaration of the “Galera-San Francisco Marine Reserve,” on the 31st of October, 2008, by the Ministry of the Environment.

 

 

The study area lies along the coastal province of Esmeraldas, between the mouth of the River Esmeraldas (N 0° 59’ 54,1’’ – W 79° 38’ 37,7’’) and the mouth of the Muisne River N 0° 37’ 3,9’’ – W 80° 02’ 01,9’’). The zone extends from the coastal profile out to 50m in depth. It encompasses 107.25 km of coastline and 106,785 hectares. The seafloor of the subtidal ecosystems in the area were characterized using the Side Scan Sonar (IMAGENEX SPORTSCAN; 330/800 kHz) and with an underwater camera (Atlantis Underwater Video Systems) and through direct observations using SCUBA, dredges (WILDLIFE SUPPLY COMPANY) and underwater photography.

map

Results:

Between June and October of 2006, over 14,610 hectares of ocean were covered using Sidescan Sonar. The total distance of transects was 795.7 km. Additionally, seafloor types were verified at 136 different points with the help of a submarine camera, dredging, and diver surveys.

The majority of the study area (64%) was made up of soft bottom, like lime, mud, and sand, and constituted a total area of 32,490.5 hectares. Hard substrates, on the other hand, such as rock or rubble, were rare (5%) and covered a total surface of 5,611.1 hectares. Finally, mixed substrates (hard surfaces interspersed among soft bottoms) covered 30% of the total study area, corresponding to a total surface of 32,490.5 hectares.

More Information:
– MAP: Proposal for the conservation of a coastal-marine protected area to the south of the Esmeraldas province. Project ESMEMAR (2,61 MB, pdf).Also available in the PUBLICATIONS section.

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