An experimental evaluation of the short-term effects of trawling on infaunal assemblages of the coast off southern Brazil

Bottom trawling is a large-scale fishing activity along the Brazilian coast, but its effects on benthic infauna are still poorly known. This is the first experimental evaluation of benthic responses to bottom trawling along the Brazilian coast. We tested the effects of trawling on macroinfaunal assemblages on the inner continental shelf off Paraná (southern Brazil) by using a sampling design with adjacent trawl and control areas. We hypothesized that if trawl fishing has a negative effect then we should expect lower numbers of species and lower benthic densities after an experimental trawling. Sampling was conducted at adjacent sites within each area to minimize confounding due to spatial variation. Five sites were sampled at a control, and five at an experimental area for infaunal and sedimentological variables. Sampling was carried out just before and one hour after experimental trawling. Multidimensional scaling followed by a PERMANOVA did not show any clear variation tendencies in the structure of the benthic assemblages in the impacted area before and after trawling. However, variance analysis showed a significant and unexpected increase in infaunal total density, in the density of the numerically dominant species (except for the polychaetes Capitella sp. and Loandalia tricuspis) and in species richness in the experimental area. Conversely, no significant variations were recorded in the control area. We suggest that the overall increase in benthic density after a disturbance is correlated with the reworking of the sediment matrix and benefits the suspension-feeders after sediment resuspension.

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Wireless Sensor Networks for Smart Cities: Network Design, Implementation and Performance Evaluation

Electronics ◽

10.3390/electronics10020218 ◽

2021 ◽

Vol 10 (2) ◽

pp. 218

Author(s):

Ala’ Khalifeh ◽

Khalid A. Darabkh ◽

Ahmad M. Khasawneh ◽

Issa Alqaisieh ◽

Mohammad Salameh ◽

...

Keyword(s):

Wireless Sensor Networks ◽

Sensor Networks ◽

Experimental Evaluation ◽

Large Scale ◽

Performance Metrics ◽

Smart Cities ◽

Field Tests ◽

Sensor Nodes ◽

Wireless Sensor ◽

Real Field

The advent of various wireless technologies has paved the way for the realization of new infrastructures and applications for smart cities. Wireless Sensor Networks (WSNs) are one of the most important among these technologies. WSNs are widely used in various applications in our daily lives. Due to their cost effectiveness and rapid deployment, WSNs can be used for securing smart cities by providing remote monitoring and sensing for many critical scenarios including hostile environments, battlefields, or areas subject to natural disasters such as earthquakes, volcano eruptions, and floods or to large-scale accidents such as nuclear plants explosions or chemical plumes. The purpose of this paper is to propose a new framework where WSNs are adopted for remote sensing and monitoring in smart city applications. We propose using Unmanned Aerial Vehicles to act as a data mule to offload the sensor nodes and transfer the monitoring data securely to the remote control center for further analysis and decision making. Furthermore, the paper provides insight about implementation challenges in the realization of the proposed framework. In addition, the paper provides an experimental evaluation of the proposed design in outdoor environments, in the presence of different types of obstacles, common to typical outdoor fields. The experimental evaluation revealed several inconsistencies between the performance metrics advertised in the hardware-specific data-sheets. In particular, we found mismatches between the advertised coverage distance and signal strength with our experimental measurements. Therefore, it is crucial that network designers and developers conduct field tests and device performance assessment before designing and implementing the WSN for application in a real field setting.

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Disease Risk, Spatial Patterns, and Incidence-Severity Relationships of Fusarium Head Blight in No-till Spring Wheat Following Maize or Soybean

Plant Disease ◽

10.1094/pdis-09-14-0944-re ◽

2015 ◽

Vol 99 (10) ◽

pp. 1360-1366 ◽

Cited By ~ 13

Author(s):

Pierri Spolti ◽

Denis A. Shah ◽

José Maurício C. Fernandes ◽

Gary C. Bergstrom ◽

Emerson M. Del Ponte

Keyword(s):

Fusarium Head Blight ◽

Large Scale ◽

Disease Risk ◽

Random Pattern ◽

Southern Brazil ◽

Head Blight ◽

Previous Crop ◽

Regional Sources ◽

Epidemiological Surveys ◽

The Relationship

The first large-scale survey of Fusarium head blight (FHB) in commercial wheat fields in southern Brazil was conducted over three years (2009 to 2011). The objectives were to: (i) evaluate whether increased FHB risk is associated with within-field maize residue; (ii) determine the spatial pattern of FHB incidence; and (iii) quantify the relationship between FHB incidence and severity. FHB was assessed in a total of 160 fields between early milk and dough. Incidence ranged from 1.0 to 89.9% (median = 25%) and severity from 0.02 to 18.6% (median = 1.3%). FHB risk was neither lower nor higher in wheat following maize than in wheat following soybean. Only 18% of fields were classified as having aggregated patterns of FHB-symptomatic spikes. A binary power law description of the variances was consistent with an overall random pattern of the disease. These results conform with the hypothesis that FHB epidemics in southern Brazil are driven by sufficient atmospherically-transported inoculum from regional sources. The incidence-severity relationship was coherent across growing season, growth stage, and previous crop; one common fitted curve described the relationship across all observations. Estimating severity from incidence may be useful in reducing the workload in epidemiological surveys.

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Effects of a 5-year trawling ban on the local benthic community in a wind farm in the Dutch coastal zone

ICES Journal of Marine Science ◽

10.1093/icesjms/fsu193 ◽

2014 ◽

Vol 72 (3) ◽

pp. 962-972 ◽

Cited By ~ 13

Author(s):

Magda J. N. Bergman ◽

Selma M. Ubels ◽

Gerard C. A. Duineveld ◽

Erik W. G. Meesters

Keyword(s):

Coastal Zone ◽

Benthic Community ◽

Large Scale ◽

Wind Farm ◽

Diversity Index ◽

Benthic Assemblages ◽

The North ◽

Wiener Diversity Index ◽

Short Period ◽

Reference Areas

Abstract As part of a large impact study in a wind farm (OWEZ) in the Dutch coastal zone, the effects of exclusion of bottom trawling on the benthic community were studied by comparison with nearby reference areas which were regularly fished. In addition to a standard boxcorer for common macrofauna, a Triple-D dredge was used to collect longer-lived, more sparsely distributed infauna and epifauna. Multivariate analysis did not reveal any difference between the assemblages in and outside OWEZ with respect to abundance, biomass, and production after a 5-year closure. The Shannon–Wiener diversity index pointed to a significantly higher diversity in OWEZ compared with some of the reference areas. A minority of the bivalve species assumed to be sensitive to trawling showed higher abundances (Spisula solida) or larger sizes (Tellina fabula, Ensis directus) in OWEZ than in some of the reference areas. In general, samples collected with the Triple-D showed more differences between areas than boxcore samples. No evidence was also found that the species composition in OWEZ relative to the reference areas had changed in the period between 1 (2007) and 5 (2011) years after closure. The change observed in all areas between 2007 and 2011 was mainly due to relatively small variations in species abundances. In conclusion, 5 years after the closure of OWEZ to fisheries, only subtle changes were measured in the local benthic community, i.e. a higher species diversity and an increased abundance and lengths of some bivalves. Depleted adult stocks, faunal patchiness, and a limited time for recovery (5 years) might explain that a significant recovery could not be found. The current study shows that designation of large-scale marine protected areas as planned for the North Sea will not automatically imply that restoration of benthic assemblages can be expected within a relatively short period of years.

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Prevent bottom trawling in southern Brazil

Science ◽

10.1126/science.abh0279 ◽

2021 ◽

Vol 372 (6538) ◽

pp. 138-138

Author(s):

Luís Gustavo Cardoso ◽

Manuel Haimovici ◽

Patrízia Raggi Abdallah ◽

Eduardo Resende Secchi ◽

Paul Gerhard Kinas

Keyword(s):

Southern Brazil ◽

Bottom Trawling

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Epilithic community development on artificial reefs deployed along a cross-shelf environmental gradient off Paraná state, southern Brazil

Brazilian Journal of Oceanography ◽

10.1590/s1679-87592011000500007 ◽

2011 ◽

Vol 59 (spe1) ◽

pp. 43-53 ◽

Cited By ~ 8

Author(s):

Frederico Brandini ◽

Ariel Scheffer da Silva

Keyword(s):

Large Scale ◽

Diversity Index ◽

Artificial Reef ◽

Larval Abundance ◽

Percent Cover ◽

Southern Brazil ◽

Factors Affecting ◽

Hydrographic Conditions ◽

One Year ◽

General Community

Concrete modules were deployed on the bottom of the 11, 18 and 30 meters isobaths along a cross-shelf hydrographic gradient off Paraná State, Southern Brazil, with the purpose of studying the colonization of sessile epilithic macroinvertebrates on artificial surfaces. After one year of submersion a total of 63 species of epilithic organisms were identified, dominated by Ostrea puelchana, Chthamalus bisinuatus, Balanus cf spongicola, Astrangia cf rathbuni, Didemnum spp, poryphers and bryozoans. Diversity index and percent cover at reef stations placed at 11, 18 and 30 meters isobaths were respectively 2.28 and 66.7%, 2.79 and 96.6% and 1.66 and 77.4%. Differences of general community structure among the three assemblages were not clearly related to the general environmental conditions at the bottom layers near the reef stations. Turbidity and larval abundance are discussed as important factors affecting colonization processes. Results indicate that depths between 15-20 meters are more suitable for the implementation of large scale artificial reef systems in the inner shelf off Paraná and, possibly, throughout the inner shelves off southern Brazil with similar hydrographic conditions.

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Influence of net-cage fish farming on zooplankton biomass in the Itá reservoir, SC, Brazil

Acta Limnologica Brasiliensia ◽

10.1590/s2179-975x2012005000014 ◽

2012 ◽

Vol 23 (4) ◽

pp. 357-367 ◽

Cited By ~ 3

Author(s):

Bruna Roque Loureiro ◽

Christina Wyss Castelo Branco ◽

Evoy Zaniboni Filho

Keyword(s):

Fish Farming ◽

Dry Weight ◽

Control Area ◽

Zooplankton Biomass ◽

Total Density ◽

Total Zooplankton ◽

Net Cage ◽

Uruguay River ◽

Cage Fish ◽

Total Zooplankton Biomass

OBJECTIVES: This study aimed to verify the influence of net-cage fish farming on zooplankton biomass in the Itá reservoir (Uruguay River, Brazil). METHODS: Samples were collected monthly from October/2009 to May/2010 at the surface and at the bottom in two sampling stations, the net-cage area and in a control area using a Van Dorn bottle and a plankton net (68 µm). RESULTS: The Cladocera and Copepoda biomass was estimated by dry weight using a micro-analytical balance, and the Rotifera biomass by Biovolume. Total zooplankton biomass varied between 6.47 and 131.56 mgDW.m-3 Calanoida copepod presented the highest value of biomass (127.56 mgDW.m-3) and rotifers, despite having an important contribution to total density, showed a maximum biomass of 2.01 mgDW.m-3. Zooplankton biomass at the net-cage area surface was higher when compared with the control area during the months of October to January. However, the zooplankton biomass was similar at the bottom of the two areas throughout the studied period. From February until May, zooplankton biomass decreased in both sampling stations, a fact probably associated with the flushing of the reservoir, followed by an increase in water transparency and a decrease in chlorophyll-a concentration in the following months (February to May). CONCLUSIONS: The influence of fish farming on zooplankton biomass was detected at the surface of the net-cage area only from October to January. From February to May this influence was not found, probably by the influence of the flushing of the reservoir.

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Marine ichthyofauna of Santa Catarina Island, Southern Brazil: checklist with comments on the species

Biota Neotropica ◽

10.1590/1676-0611-bn-2018-0684 ◽

2019 ◽

Vol 19 (3) ◽

Author(s):

Gisela Costa Ribeiro ◽

André Pereira Cattani ◽

Mauricio Hostim-Silva ◽

Leandro Clezar ◽

Ana Carolina dos Passos ◽

...

Keyword(s):

Conservation Status ◽

Species Distributions ◽

Marine Fishes ◽

Brazilian Coast ◽

Coastal Environments ◽

Southern Brazil ◽

Santa Catarina ◽

Western Atlantic ◽

The Caribbean ◽

Brazilian Province

Abstract: This study aimed to present a checklist of marine fishes from coastal environments of the Island of Santa Catarina, including comments on the zoogeographic affinities, conservation status of each species, and functional groups. A total of 169 fish species belonging to 30 orders and 58 families were recorded. The most speciose families were Sciaenidae, Carangidae and, Engraulidae, representing 26,62% of the recorded species. Anchoa was the richest genus, followed by Sphoeroides and Cynoscion. Most of the species have their distribution limited to the western Atlantic, and two groups of fish were distinguished according to the species distributions: 1) species occurring in the Caribbean and in the Brazilian Province; and 2) Transatlantic species. Thirteen species are critically threatened, 10 are overexploited on the Brazilian coast, and 2 are threatened by extinction. Most of the species are either marine stragglers or marine migrants, and most of them are zoobenthivores, piscivores, or both.

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Community-based Oral Health Education Program in a Rural Population of Haryana: A 25 years Experience

Journal of Postgraduate Medicine Education and Research ◽

10.5005/jp-journals-10028-1156 ◽

2015 ◽

Vol 49 (3) ◽

pp. 101-104

Author(s):

Amrit Tewari ◽

Utkal Mohanty ◽

Ashima Goyal

Keyword(s):

Health Promotion ◽

Oral Health ◽

Health Education ◽

Education Program ◽

Control Area ◽

Health Education Program ◽

Oral Health Promotion ◽

Community Based ◽

Oral Health Education ◽

Experimental Area

ABSTRACT Background An Indian Council of medical Research (ICMR) task force project was started in 1985 covering a population of 120,000 of Raipur Rani block of Haryana to study the feasibility of implementation of oral health promotion and prevention in the community and in the schools by utilizing existing manpower at different sectors. Objectives (i) To evaluate the long-term role of healthcare workers in imparting primary preventive strategies of oral health to adult community (ii) To study the knowledge, attitude and practice of the community regarding oral health. Methodology A total of 600 households (300 in experimental block and 300 in control block) were included by stratified random sampling method depending on the distance from Community Health centre of Raipur Rani to assess KAP and Caries activity among the population. Results The use of toothbrush as an oral hygiene method is being practiced by 96.6% of population in the experimental area compared to 84% in the control population where no oral health promotion activity was carried out. A great variation was seen in the frequency of its usage; 56% of the population in experimental area brushes twice per day compared to 7% of control area. According to the present data, 80% of the population in the experimental area is aware about the etiology, progress and consequences of gum diseases due to continuous oral health education delivered by the trained health staff during their routine beat program. In the control area where no oral health program was implemented, this knowledge was seen in 22 to 35% of the population. Conclusion In a developing country like India there is a pressing need of community-based oral health programs to reduce the burden of oral diseases, improve quality of life and reduce out of pocket expenditure incurring toward treatment of these diseases. How to cite this article Goyal A, Gauba K, Mohanty U, Tewari A. Community-based Oral Health Education Program in a Rural Population of Haryana: A 25 years Experience. J Postgrad Med Edu Res 2015;49(3):101-104.

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Winter migration and diving behaviour of porbeagle shark, Lamna nasus, in the Northeast Atlantic

ICES Journal of Marine Science ◽

10.1093/icesjms/fsq145 ◽

2010 ◽

Vol 68 (1) ◽

pp. 166-174 ◽

Cited By ~ 28

Author(s):

Ryan A. Saunders ◽

François Royer ◽

Maurice W. Clarke

Keyword(s):

Spatial Ecology ◽

Large Scale ◽

Depth Distribution ◽

Diving Behaviour ◽

Depth Range ◽

Bay Of Biscay ◽

Night Time ◽

Fishing Activity ◽

Northeast Atlantic ◽

Winter Migration

Abstract Saunders, R. A., Royer, F., and Clarke, M. W. 2011. Winter migration and diving behaviour of porbeagle shark, Lamna nasus, in the Northeast Atlantic. – ICES Journal of Marine Science, 68: 166–174. The porbeagle is one of the top marine predators in the North Atlantic. However, little is known about its biology, abundance, or spatial ecology there. Results are presented on the migration and behaviour of three porbeagles tagged with archival pop-up tags off Ireland between September 2008 and January 2009. One shark migrated >2400 km to the northwest of Morocco, residing around the Bay of Biscay for approximately 30 days. The other two remained more localized in off-shelf regions around the Celtic Sea/Bay of Biscay and off western Ireland. The sharks occupied a broad vertical depth range (0–700 m) and a relatively limited temperature range (∼9–17°C), with notable variations in diving behaviour between individual sharks. There were distinct day–night differences in depth distribution, each shark being positioned higher in the water column by night than by day. Night-time depth distribution also appeared to be driven by the lunar cycle during broad-scale migration through oceanic waters. Our results show that porbeagles occupy and traverse regions of high fishing activity where they are potentially vulnerable to population depletion. Such large-scale movement outside the ICES Area underlines the need for international coordination in their assessment and management.

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