scholarly journals Quick and cost-effective mapping of subsistence and artisanal fishing areas within and adjacent to a marine protected area

2021 ◽  
Vol 20 (1) ◽  
pp. 63-70
Author(s):  
Marcos A.M. Pereira ◽  
Tânia I.F.C. Pereira ◽  
Cristina M.M. Louro ◽  
Carlos Litulo ◽  
Raquel S. Fernandes
Keyword(s):  
Spatial Information ◽  
Marine Protected Area ◽  
Marine Reserve ◽  
River Mouth ◽  
Cost Effective ◽  
Small Scale ◽  
Western Boundary ◽  
Artisanal Fishing ◽  
The North ◽  
Mapping Software

Spatial information on artisanal fisheries is largely lacking, making subsequent management and threat or impact assessments difficult. Local knowledge, current and readily available mapping software and Global Positioning System (GPS) techniques were used to map small-scale (subsistence and artisanal) fishing areas within and adjacent to the western boundary of the Ponta do Ouro Partial Marine Reserve in southern Mozambique. Data on habitat types were collected in the field and combined with available literature. Thirty-one fishing areas were identified and mapped resulting in a total area of 293.1 km2 with a perimeter of 396.7 km, from the Inhaca Island lighthouse in the north to the Maputo River mouth in the south. Habitats within the fishing areas included isolated intertidal sand banks, seagrass beds, estuarine channels, as well as intertidal muddy areas adjacent to the coast. The fishing areas covered on average 9.5 km2 (SD=12.0) and varied immensely in size (0.3–50.1 km2). Overall, 58.4 % (171.2 km2) of the total fishing area mapped was located inside the reserve. Costs associated with data collection equated to an average of U$D 3.61 per mapped km2 or U$D 2.63 per km tracked. The method was found to be quick, cost-effective and easily replicable elsewhere.

scholarly journals Sensitivity of winter North Atlantic-European climate to resolved atmosphere and ocean dynamics

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Reindert J. Haarsma ◽  
Javier García-Serrano ◽  
Chloé Prodhomme ◽  
Omar Bellprat ◽  
Paolo Davini ◽  
...  
Keyword(s):  
Atmospheric Circulation ◽  
North Atlantic ◽  
Gulf Stream ◽  
Ocean Dynamics ◽  
Small Scale ◽  
Western Boundary ◽  
The North ◽  
The North Atlantic ◽  
Mean Climate ◽  
Meso Scale

Abstract Northern Hemisphere western boundary currents, like the Gulf Stream, are key regions for cyclogenesis affecting large-scale atmospheric circulation. Recent observations and model simulations with high-temporal and -spatial resolution have provided evidence that the associated ocean fronts locally affect troposphere dynamics. A coherent view of how this affects the mean climate and its variability is, however, lacking. In particular the separate role of resolved ocean and atmosphere dynamics in shaping the atmospheric circulation is still largely unknown. Here we demonstrate for the first time, by using coupled seasonal forecast experiments at different resolutions, that resolving meso-scale oceanic variability in the Gulf Stream region strongly affects mid-latitude interannual atmospheric variability, including the North Atlantic Oscillation. Its impact on climatology, however, is minor. Increasing atmosphere resolution to meso-scale, on the other hand, strongly affects mean climate but moderately its variability. We also find that regional predictability relies on adequately resolving small-scale atmospheric processes, while resolving small-scale oceanic processes acts as an unpredictable source of noise, except for the North Atlantic storm-track where the forcing of the atmosphere translates into skillful predictions.

Occurrence of juvenile bull sharks (Carcharhinus leucas) in the Navua River in Fiji

2017 ◽  
Vol 68 (3) ◽  
pp. 592 ◽  
Author(s):  
Diego Cardeñosa ◽  
Kerstin B. J. Glaus ◽  
Juerg M. Brunnschweiler
Keyword(s):  
Marine Protected Area ◽  
Marine Reserve ◽  
Species Conservation ◽  
Morphological Characteristics ◽  
River Mouth ◽  
Reproductive Activity ◽  
Carcharhinus Leucas ◽  
Large Numbers ◽  
Poor Region ◽  
White Belly

Effective species conservation requires the protection of all stages of its life-cycle. The Shark Reef Marine Reserve (SRMR) in Fiji is a marine protected area where large numbers of adult bull sharks (Carcharhinus leucas) congregate due to food provisioning. At the end of a calendar year bull sharks leave the area for reproductive activity, but parturition sites are still unknown. Between February 2014 and January 2015, we interviewed local fishermen and conducted a fishing survey, so as to assess presence and abundance of bull sharks in the Navua River near the SRMR. In total 84% of fishermen reported either seeing or catching sharks up to 8km upriver from the river mouth. They described them as small sharks having a rounded snout and being grey–brown in colour with a white belly, morphological characteristics that match juvenile bull sharks. During the fishing survey, a total of nine juvenile bull sharks were captured, including two that were recaptured after 108 and 92 days at liberty. Our findings confirmed the presence of bull sharks in the Navua River and provide a preliminary characterisation of a potential shark parturition or nursery area from a data-poor region.

Local Scour and Protection of F3 Offshore GBS Platform

2002 ◽  
Author(s):  
Klaas Jan Bos ◽  
Zhiwen Chen ◽  
Henk J. Verheij ◽  
Martijn Onderwater ◽  
Mees Visser
Keyword(s):  
Cost Effective ◽  
Model Tests ◽  
Local Scour ◽  
Protection System ◽  
Small Scale ◽  
Field Observations ◽  
Empirical Formulas ◽  
The North ◽  
Survey Strategy ◽  
Scour Protection

In 1992 a GBS (Gravity Based Structure) was placed in the F3 block in the Dutch sector of the North Sea. Gabion mattresses around the GBS were applied to prevent scour. The potential scour and the required dimensions of the gabion mattresses were determined before the installation in small-scale physical model tests. After the installation of the GBS, annual surveys have been carried out to provide information about the scour development around the GBS and the status of the protection system. This paper presents field observations of local scour development around the F3 GBS platform and an evaluation of the performance of the scour protection system. The objectives were to assess the maximum scour around the GBS and to determine a cost-effective survey strategy. To assess the maximum scour around the GBS, metocean conditions for the F3 GBS location were hindcasted for the period between the platform installation and the latest survey. The observed scour depths were analysed and compared with predictions both from the model tests and from existing empirical formulas. The results showed that the predicted scour depths based on the model tests agree reasonably well with the field observations. The empirical formulas give larger scour depths than the surveys. Based on the field observations in combination with predictions of the models, the maximum scour depths under the design extreme environmental conditions have been determined. To determine a cost effective survey strategy, the behaviour and performance of the gabion mattresses were evaluated based on the annual surveys and video inspections. It was concluded that the protection system has functioned well and no damage was observed. On the basis of the maximum expected scour and the performance of the gabion mattresses, it was considered that the survey frequency may be reduced. Surveys and inspections may be carried out every three years instead of every year, and after a severe storm.

scholarly journals Semi-Adiabatic Model of the Deep Stratification and Meridional Overturning

2011 ◽  
Vol 41 (4) ◽  
pp. 757-780 ◽  
Author(s):  
Timour Radko ◽  
Igor Kamenkovich
Keyword(s):  
Large Scale ◽  
Formation Rate ◽  
Three Dimensional ◽  
Meridional Overturning Circulation ◽  
Small Scale ◽  
Western Boundary ◽  
Meridional Transport ◽  
The North ◽  
Meridional Overturning ◽  
Circumpolar Current

An analytical model of the Atlantic deep stratification and meridional overturning circulation is presented that illustrates the dynamic coupling between the Southern Ocean and the midlatitude gyres. The model, expressed here in terms of the two-and-a-half-layer framework, predicts the stratification and meridional transport as a function of the mechanical and thermodynamic forcing at the sea surface. The approach is based on the classical elements of large-scale circulation theory—ideal thermocline, inertial western boundary currents, and eddy-controlled Antarctic Circumpolar Current (ACC) models—which are combined to produce a consistent three-dimensional view of the global overturning. The analytical tractability is achieved by assuming and subsequently verifying that the pattern of circulation in the model is largely controlled by adiabatic processes: the time-mean and eddy-induced isopycnal advection of buoyancy. The mean stratification of the lower thermocline is determined by the surface forcing in the ACC and, to a lesser extent, by the North Atlantic Deep Water formation rate. Although the vertical small-scale mixing and the diapycnal eddy-flux components can substantially influence the magnitude of overturning, their effect on the net stratification of the midlatitude ocean is surprisingly limited. The analysis in this paper suggests the interpretation of the ACC as an active lateral boundary layer that does not passively adjust to the prescribed large-scale solution but instead forcefully controls the interior pattern.

Urban pollution control strategy: SBR technology to treat agricultural waste from pig farm in Indonesia

2019 ◽  
Vol 2 (2) ◽  
pp. 21
Author(s):  
Lindawati Lindawati
Keyword(s):  
Cost Estimation ◽  
Batch Reactor ◽  
Agricultural Waste ◽  
Cost Effective ◽  
Land Application ◽  
Pig Manure ◽  
Small Scale ◽  
Piggery Wastewater ◽  
Pig Farm ◽  
Number Of Customers

Reduction of food rations and shortages is one of the impacts of the increasing human population. Food sector industries then try to cope with the fast growing number of customers. Agribusiness sector gains its popularity in these recent years, including pig farm. The increase trend of animal farming industry is likely to bring increasing pollution problem unless effective treatment methods are used. The main problems related to the pig farm include odor nuisance and pig manure disposal. The existing land application of piggery wastewater is the traditional way to discharge the wastewater. This may yield in land and water contamination, due to the accumulation of unused nutrients by crop plant. A case study of a large commercial pig farm from Australia is proposed to apply in smaller scale in Indonesia. Operational strategies for the small-scale SBR (Sequencing Batch Reactor) treating piggery effluent were developed based on lab-scale experiments. Due to SBR characteristics, which are money-saving and space-saving, it is very suitable to be applied in urban area. An economic evaluation was made of various process options. The cost estimation showed that SBR is a cost effective process, allowing operational batches to be adjusted to reduce unnecessary aeration cost. A reduction in the aeration cost was achieved by shortening the batch time from 24-h to 8-h. A comparison of three different SBR options showed that smaller size reactors could be more flexible and cost effective when compared with the larger ones.

Assessment of Turbulent Processes in Lake Kinneret by the Two-Dimensional Reservoir Water Quality Model “Better”

1993 ◽  
Vol 27 (7-8) ◽  
pp. 381-385 ◽  
Author(s):  
Y. Oziransky ◽  
B. Shteinman
Keyword(s):  
Water Body ◽  
River Mouth ◽  
Temporal Distribution ◽  
Lake Kinneret ◽  
Toxic Substances ◽  
Two Dimensional ◽  
Quality Model ◽  
Reservoir Water ◽  
The North ◽  
Longitudinal Gradients

Data of high spatial and temporal resolution, and a special sampling program are essential for successful application of mathematical models designed to reproduce observed seasonal patterns of temperature, dissolved oxygen, nutrients, pH, and algal biomass for both vertical and longitudinal gradients in a water body. Lake Kinneret suspended solids are of great potential value for estimating transport, exposure to water body elements, and fate of many toxic substances. Therefore the distribution of admixtures in two longitudinal and five vertical segmentation schemes were examined with the two-dimensional water body quality box model “BETTER” (Bender et al, 1990). The transects were taken in the north-western part of Lake Kinneret close to the Jordan River mouth and the National Water Carrier (NWC) head pumping station. The outflow volumes were given according to regular sampling of natural speed of water outflow from different lake layers under calm conditions. Temporal distribution of mixing concentrations as well as turbulent diffusion horizontal coefficients due to the spatial distribution of turbulent scale were obtained during the model's run with the December 1991 data.

scholarly journals Ritual Economy and the Organization of Scioto Hopewell Craft Production: Insights from the Outskirts of the Mound City Group

2020 ◽  
Vol 85 (2) ◽  
pp. 279-304
Author(s):  
Timothy D. Everhart ◽  
Bret J. Ruby
Keyword(s):  
Craft Production ◽  
Small Scale ◽  
Magnetic Survey ◽  
Middle Woodland ◽  
The North ◽  
Large Structures ◽  
Production Site ◽  
Production And Consumption ◽  
Ritual Economy ◽  
City Group

This article offers insights into the organization of Scioto Hopewell craft production and examines the implications of this organization through the lens of ritual economy. We present a novel analysis of investigations at the North 40 site, concluding that it is a craft production site located on the outskirts of the renowned Mound City Group. High-resolution landscape-scale magnetic survey revealed a cluster of three large structures and two rows of associated pits; one of the buildings and three of the pits were sampled in excavations. Evidence from the North 40 site marks this as the best-documented Scioto Hopewell craft production site. Mica, chert, and copper were crafted here in contexts organized outside the realm of domestic household production and consumption. Other material remains from the site suggest that crafting was specialized and embedded in ceremonial contexts. This analysis of the complex organization of Scioto Hopewell craft production provides grounds for further understanding the elaborate ceremonialism practiced by Middle Woodland (AD 1–400) societies and adds to the known complexity of craft production in small-scale societies. Furthermore, this article contributes to a growing body of literature demonstrating the utility of ritual economy as a framework for approaching the sociality of small-scale societies.

scholarly journals Reference frames in spatial communication for navigation and sports: an empirical study in ultimate frisbee players

2020 ◽  
Vol 5 (1) ◽  
Author(s):  
Steven M. Weisberg ◽  
Anjan Chatterjee
Keyword(s):  
Reference Frame ◽  
Reference Frames ◽  
Spatial Information ◽  
Spatial Reference ◽  
Spatial Reference Frames ◽  
The North ◽  
Communication Task ◽  
Spatial Communication ◽  
Spatial Domains ◽  
Ultimate Frisbee

Abstract Background Reference frames ground spatial communication by mapping ambiguous language (for example, navigation: “to the left”) to properties of the speaker (using a Relative reference frame: “to my left”) or the world (Absolute reference frame: “to the north”). People’s preferences for reference frame vary depending on factors like their culture, the specific task in which they are engaged, and differences among individuals. Although most people are proficient with both reference frames, it is unknown whether preference for reference frames is stable within people or varies based on the specific spatial domain. These alternatives are difficult to adjudicate because navigation is one of few spatial domains that can be naturally solved using multiple reference frames. That is, while spatial navigation directions can be specified using Absolute or Relative reference frames (“go north” vs “go left”), other spatial domains predominantly use Relative reference frames. Here, we used two domains to test the stability of reference frame preference: one based on navigating a four-way intersection; and the other based on the sport of ultimate frisbee. We recruited 58 ultimate frisbee players to complete an online experiment. We measured reaction time and accuracy while participants solved spatial problems in each domain using verbal prompts containing either Relative or Absolute reference frames. Details of the task in both domains were kept as similar as possible while remaining ecologically plausible so that reference frame preference could emerge. Results We pre-registered a prediction that participants would be faster using their preferred reference frame type and that this advantage would correlate across domains; we did not find such a correlation. Instead, the data reveal that people use distinct reference frames in each domain. Conclusion This experiment reveals that spatial reference frame types are not stable and may be differentially suited to specific domains. This finding has broad implications for communicating spatial information by offering an important consideration for how spatial reference frames are used in communication: task constraints may affect reference frame choice as much as individual factors or culture.

Opportunities to improve sustainability of a Marine Protected Area: Small-scale fishing in Loreto, Baja California Sur, México

2021 ◽  
pp. 101852
Author(s):  
Miguel Armenta-Cisneros ◽  
Miguel Angel Ojeda-Ruiz ◽  
Elvia Aida Marín-Monroy ◽  
Alfredo Flores-Irigoyen
Keyword(s):  
Protected Area ◽  
Baja California ◽  
Marine Protected Area ◽  
Small Scale ◽  
Baja California Sur

scholarly journals Cognitive map formation through haptic and visual exploration of tactile city-like maps

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Loes Ottink ◽  
Marit Hoogendonk ◽  
Christian F. Doeller ◽  
Thea M. Van der Geest ◽  
Richard J. A. Van Wezel
Keyword(s):  
Visual Information ◽  
Spatial Information ◽  
Cognitive Map ◽  
Visual Exploration ◽  
Distinct Advantage ◽  
Small Scale ◽  
Map Learning ◽  
Scale Models ◽  
Spatial Tasks ◽  
Tactile Maps

AbstractIn this study, we compared cognitive map formation of small-scale models of city-like environments presented in visual or tactile/haptic modalities. Previous research often addresses only a limited amount of cognitive map aspects. We wanted to combine several of these aspects to elucidate a more complete view. Therefore, we assessed different types of spatial information, and consider egocentric as well as allocentric perspectives. Furthermore, we compared haptic map learning with visual map learning. In total 18 sighted participants (9 in a haptic condition, 9 visuo-haptic) learned three tactile maps of city-like environments. The maps differed in complexity, and had five marked locations associated with unique items. Participants estimated distances between item pairs, rebuilt the map, recalled locations, and navigated two routes, after learning each map. All participants overall performed well on the spatial tasks. Interestingly, only on the complex maps, participants performed worse in the haptic condition than the visuo-haptic, suggesting no distinct advantage of vision on the simple map. These results support ideas of modality-independent representations of space. Although it is less clear on the more complex maps, our findings indicate that participants using only haptic or a combination of haptic and visual information both form a quite accurate cognitive map of a simple tactile city-like map.

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