Spatial distribution of southern brown shrimp (Farfantepenaeus subtilis) on the Amazon continental shelf: a fishery, marine geology and GIS integrated approach

Abstract The spatial distribution of the southern brown shrimp Farfantepenaeus subtilis (Pérez-Farfante, 1967) was studied based on industrial fishing fleet activities and is associated with geological and oceanographic characteristics of the benthonic environments on the Amazon continental shelf. Using a geographical information system (GIS) this paper sought to calculate the relative abundance of brown shrimp based on catch per unit effort (CPUE) and compare it with bathymetry, type of sedimentary structure, sedimentation rate and bottom salinity. As a result, we have concluded that the relative abundance (in terms of CPUE) is not uniformly distributed in space. Spatial analysis indicates that commercial trawling efforts were made in the (foreset) region of the subaqueous Amazon delta at depths of 40 to 60 m. In this region, prawn are responsible for the bioturbation of the sediments and the creation of a sedimentary structure called mottled mud. In the foreset region, sedimentation rates progressively increased up to 10 cm.yr-1; re-suspension was reduced and bottom salinity was high (~ 36). It appears that all of these factors define a stable muddy area with intense bioturbation. This notable biological activity is to be explained by the occurrence of a high F. subtilis abundance that appears to originate in a microbial loop. We concluded that by combining fishery information with environmental data from a GIS, it was possible to identify abundance distribution patterns for southern brown shrimp and other economically important fishery resources and to understand how they change on a large spatial-scale.

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Does habitat or depth influence catch rates of pelagic species?

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f07-115 ◽

2007 ◽

Vol 64 (11) ◽

pp. 1581-1594 ◽

Cited By ~ 65

Author(s):

Keith A Bigelow ◽

Mark N Maunder

Keyword(s):

Relative Abundance ◽

Environmental Conditions ◽

Environmental Data ◽

Catch Per Unit Effort ◽

Blue Shark ◽

Species Vulnerability ◽

Thunnus Obesus ◽

Catch Rates ◽

The Relationship ◽

The Vertical Distribution

The efficiency of a pelagic longline fishing operation and the species composition of the resulting catch is influenced primarily by the relationship between the distribution of hooks and species vulnerability, with vulnerability described by either depth or some suite of environmental variables. We therefore fitted longline catch rate models to determine whether catch is estimated better by vertically distributing a species by depth or by environmental conditions (e.g., temperature, thermocline gradient, and oxygen concentration). Catch rates were estimated by two methods: (i) monitoring longlines where the vertical distribution of hooks and catch in relation to depth and environmental conditions is known, and (ii) applying a statistical habitat-based standardization (statHBS) model to fishery and environmental data to develop relative abundance indices for bigeye tuna (Thunnus obesus) and blue shark (Prionace glauca). Results indicated that an understanding of gear dynamics and environmental influences are important for analyzing catch-per-unit-effort (CPUE) data correctly. Analyses based on depth-specific catch rates can lead to serious misinterpretation of abundance trends, despite the use of sophisticated statistical techniques (e.g., generalized linear mixed models). This illustrates that inappropriate inclusion or exclusion of important covariates can bias estimates of relative abundance, which may be a common occurrence in CPUE analysis.

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Factors influencing spatial distribution and growth of juvenile lake sturgeon (Acipenser fulvescens)

Canadian Journal of Zoology ◽

10.1139/cjz-2015-0058 ◽

2015 ◽

Vol 93 (11) ◽

pp. 823-831 ◽

Cited By ~ 10

Author(s):

Cameron C. Barth ◽

W. Gary Anderson

Keyword(s):

Spatial Distribution ◽

Relative Abundance ◽

Condition Factor ◽

Abiotic Factors ◽

Distribution Patterns ◽

Lake Sturgeon ◽

Conservation Strategies ◽

Acipenser Fulvescens ◽

Catch Per Unit Effort ◽

Fourth Section

Understanding biotic and abiotic factors that influence spatial distribution patterns, condition factor, and growth of lotic fish species within river impoundments is essential for the development of effective management and conservation strategies. This study aimed to compare relative abundance, condition factor, and growth rate of juvenile lake sturgeon (Acipenser fulvescens Rafinesque, 1817) among eight sections of a 41 km long impoundment of the Winnipeg River, Manitoba, Canada. Relative abundance of juvenile lake sturgeon, as measured by catch per unit effort (CPUE), was 3–6 times greater in the two farthest upstream sections when compared with the five farthest downstream sections. Growth in length was slowest for individuals captured in the two farthest upstream sections, moderate in the third section, and highest in the fourth section, with individuals from the fourth section attaining lengths approximately double those from the two farthest upstream sections by age 6. Condition factor varied among sections of the impoundment in a pattern similar to that observed for growth. Given similarities in many environmental factors such as water temperature and water chemistry among sections of this study area, our results provide important insight into how abiotic and biotic factors, combined with behavioural characteristics of this species, may influence distribution patterns and growth of juvenile lake sturgeon within river impoundments.

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Geographical Information System “Meets” Environmental Data Management: Exemplified at Practical Projects

GI_Forum 2013 – Creating the GISociety ◽

10.1553/giscience2013s113 ◽

2013 ◽

Author(s):

Keyword(s):

Information System ◽

Data Management ◽

Geographical Information System ◽

Environmental Data ◽

Geographical Information

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Aquatic and semi aquatic Hemiptera community of Sonebeel, the largest wetland of Assam, northeastern India

Journal of Threatened Taxa ◽

10.11609/jott.3440.10.13.12792-12799 ◽

2018 ◽

Vol 10 (13) ◽

pp. 12792-12799

Author(s):

Anupama Saha ◽

Susmita Gupta

Keyword(s):

Species Richness ◽

Pest Control ◽

Relative Abundance ◽

Species Distribution ◽

Diversity Indices ◽

Environmental Data ◽

Northeastern India ◽

Ecological Roles

Aquatic and semiaquatic Hemiptera bugs play significant ecological roles, and they are important indicators and pest control agents. Little information is currently available concerning its populations in southern Assam. This study assessed hemipterans in four sites of Sonebeel, the largest wetland in Assam (3458.12 ha at full storage level), situated in Karimganj District. The major inflow and outflow of the wetland are the rivers Singla and Kachua, respectively (the Kachua drains into the Kushiyara River). Samples were trapped with pond nets and were seasonally recorded. This study recorded a total of 28 species of aquatic and semiaquatic hemipterans belonging to 20 genera under nine families. Population, geographical and environmental data (e.g., rainfall) were used to assess the relative abundance of species, species richness and different diversity indices, and species distribution.

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Ecological and environmental factors affecting the foraging activity of the White-bellied Heron Ardea insignis (Hume, 1878) in Bhutan

Bird Conservation International ◽

10.1017/s0959270920000684 ◽

2021 ◽

pp. 1-18

Author(s):

PEMA KHANDU ◽

GEORGE A. GALE ◽

SARA BUMRUNGSRI

Keyword(s):

Relative Abundance ◽

Habitat Restoration ◽

Prey Species ◽

Catch Per Unit Effort ◽

Factors Affecting ◽

Prey Biomass ◽

Gravel Mining ◽

Unit Effort ◽

Prey Preferences ◽

The Government

Summary White-bellied Heron Ardea insignis (WBH) is critically endangered, but we lack data on many aspects of its basic ecology and threats to the species are not clearly understood. The goal of this study was to analyse WBH foraging microhabitat selection, foraging behaviour, and prey preferences in two river basins (Punatsangchhu and Mangdechhu) in Bhutan which are likely home to one of the largest remaining populations of WBH. We also explored the relationship between the relative abundance of the WBH and prey biomass catch per unit effort within four foraging river microhabitats (pool, pond, riffle and run). Prey species were sampled in 13 different 100-m thalweg lengths of the rivers using cast nets and electrofishing gear. Riffles and pools were the most commonly used microhabitats; relative abundance was the highest in riffles. The relative abundance of WBH and prey biomass catch per unit effort (CPUE) also showed a weak but significant positive correlation (rs = 0.22). The highest biomass CPUE was observed in riffles while the lowest was found in the ponds. From the 97 prey items caught by the WBH, 95% of the prey were fish. The WBH mainly exploited three genera of fish (Garra, Salmo, and Schizothorax) of which Schizothorax (64%) was the most frequently consumed. This study provides evidence in support of further protection of critical riverine habitat and fish resources for this heron. Regular monitoring of sand and gravel mining, curbing illegal fishing, habitat restoration/mitigation, and developing sustainable alternatives for local people should be urgently implemented by the government and other relevant agencies. Further study is also required for understanding the seasonal variation and abundance of its prey species in their prime habitats along the Punatsangchhu and Mangdechhu basins.

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Cohort profile: the Chinese Pregnant Women Cohort Study and Offspring Follow-up (CPWCSaOF)

BMJ Open ◽

10.1136/bmjopen-2020-044933 ◽

2021 ◽

Vol 11 (3) ◽

pp. e044933

Author(s):

Tianchen Lyu ◽

Yunli Chen ◽

Yongle Zhan ◽

Yingjie Shi ◽

Hexin Yue ◽

...

Keyword(s):

Cohort Study ◽

Pregnant Women ◽

First Trimester ◽

Health Problems ◽

Environmental Data ◽

Geographical Information ◽

Obstetric Outcomes ◽

Factors Affecting ◽

Link Type

PurposeA multicentre prospective cohort study, known as the Chinese Pregnant Women Cohort Study (CPWCS), was established in 2017 to collect exposure data during pregnancy (except environmental exposure) and analyse the relationship between lifestyle during pregnancy and obstetric outcomes. Data about mothers and their children’s life and health as well as children’s laboratory testing will be collected during the offspring follow-up of CPWCS, which will enable us to further investigate the longitudinal relationship between exposure in different periods (during pregnancy and childhood) and children’s development.Participants9193 pregnant women in 24 hospitals in China who were in their first trimester (5–13 weeks gestational age) from 25 July 2017 to 26 November 2018 were included in CPWCS by convenience sampling. Five hospitals in China which participated in CPWCS with good cooperation will be selected as the sample source for the Chinese Pregnant Women Cohort Study (Offspring Follow-up) (CPWCS-OF).Findings to dateSome factors affecting pregnancy outcomes and health problems during pregnancy have been discovered through data analysis. The details are discussed in the ‘Findings to date’ section.Future plansInfants and children and their mothers who meet the criteria will be enrolled in the study and will be followed up every 2 years. The longitudinal relationship between exposure (questionnaire data, physical examination and biospecimens, medical records, and objective environmental data collected through geographical information system and remote sensing technology) in different periods (during pregnancy and childhood) and children’s health (such as sleeping problem, oral health, bowel health and allergy-related health problems) will be analysed.Trail registration numberCPWCS was registered with ClinicalTrials.gov on 18 January 2018: NCT03403543. CPWCS-OF was registered with ClinicalTrials.gov on 24 June 2020: NCT04444791.

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Modelling Maritime Pine (Pinus pinaster Aiton) Spatial Distribution and Productivity in Portugal: Tools for Forest Management

Forests ◽

10.3390/f12030368 ◽

2021 ◽

Vol 12 (3) ◽

pp. 368

Author(s):

Cristina Alegria ◽

Natália Roque ◽

Teresa Albuquerque ◽

Paulo Fernandez ◽

Maria Margarida Ribeiro

Keyword(s):

Spatial Distribution ◽

Forest Management ◽

Species Distribution ◽

Pinus Pinaster ◽

Landscape Planning ◽

Environmental Data ◽

Maritime Pine ◽

Future Climate Change ◽

Sequential Simulation ◽

Model Species

Research Highlights: Modelling species’ distribution and productivity is key to support integrated landscape planning, species’ afforestation, and sustainable forest management. Background and Objectives: Maritime pine (Pinus pinaster Aiton) forests in Portugal were lately affected by wildfires and measures to overcome this situation are needed. The aims of this study were: (1) to model species’ spatial distribution and productivity using a machine learning (ML) regression approach to produce current species’ distribution and productivity maps; (2) to model the species’ spatial productivity using a stochastic sequential simulation approach to produce the species’ current productivity map; (3) to produce the species’ potential distribution map, by using a ML classification approach to define species’ ecological envelope thresholds; and (4) to identify present and future key factors for the species’ afforestation and management. Materials and Methods: Spatial land cover/land use data, inventory, and environmental data (climate, topography, and soil) were used in a coupled ML regression and stochastic sequential simulation approaches to model species’ current and potential distributions and productivity. Results: Maritime pine spatial distribution modelling by the ML approach provided 69% fitting efficiency, while species productivity modelling achieved only 43%. The species’ potential area covered 60% of the country’s area, where 78% of the species’ forest inventory plots (1995) were found. The change in the Maritime pine stands’ age structure observed in the last decades is causing the species’ recovery by natural regeneration to be at risk. Conclusions: The maps produced allow for best site identification for species afforestation, wood production regulation support, landscape planning considering species’ diversity, and fire hazard mitigation. These maps were obtained by modelling using environmental covariates, such as climate attributes, so their projection in future climate change scenarios can be performed.

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