Bathymetric Distribution of Brittlestars (Ophiuroidea) Collected off the Northern Oregon Coast

1965 ◽  
Vol 22 (6) ◽  
pp. 1407-1424 ◽  
Author(s):  
Sergei Astrahantseff ◽  
Miles S. Alton
Keyword(s):  
Atomic Energy Commission ◽  
River Mouth ◽  
Benthic Fauna ◽  
Columbia River ◽  
Single Species ◽  
Species Number ◽  
Bathymetric Distribution ◽  
Number Of Species ◽  
Study Species ◽  
Benthic Zone

A cooperative study by the Bureau of Commercial Fisheries and the U. S. Atomic Energy Commission was undertaken to evaluate the composition of benthic fauna indigenous to waters adjacent to the Columbia River mouth. Standard stations were established by 25-fath intervals between 50 and 500 fath, and by 50-fath intervals from 500 to 1050 fath. Fifty- to 500-fath stations were monitored seasonally while sampling of deeper stations was generally restricted to spring and summer cruises.Twenty-four species of ophiuroids representing eight families and 14 genera were collected during this study. Species number varied by station ranging from one at 650 fath to a maximum of nine species at 300 fath.The number of species of ophiuroids by benthic zone showed a general increase with increasing depth. The total number of species collected by benthic zone was 4 from the sublittoral, 8 from the upper bathyal, 13 from the lower bathyal, and 15 from the abyssal. One, three, and eight species were confined to the outer sublittoral, lower bathyal, and abyssal, respectively.The highest availability of ophiuroids occurred between 150 and 250 fath and between 800 and 1050 fath. Lowest availability occurred at 125, 325, and 350 fath where few or no ophiuroids were observed. Larger catches of ophiuroids were estimated to contain from 500 to 2000 individuals. A single species, Ophiura sarsii, consistently dominated catches from 150 to 250 fath; while four species, Ophiocten pacificum, Ophiolimna bairdi, Ophiomusium lymani, and Ophiophthalmus normani, dominated catches between 800 and 1050 fath.The families Ophiuridae and Ophiacanthidae predominate in the study area. Together, they account for the majority of species collected which include the five most abundant species.The bathymetric distribution of ophiuroids from the Columbia River trackline illustrates a changing species composition with increasing depth, with the existence of both stenobathic and eurybathic species.

Temporal patterns in the macrobenthic communities of the Hawkesbury estuary, New South Wales

1987 ◽  
Vol 38 (5) ◽  
pp. 607
Author(s):  
AR Jones
Keyword(s):  
Community Composition ◽  
Temporal Patterns ◽  
Single Species ◽  
Species Number ◽  
Community Patterns ◽  
Low Salinity ◽  
Number Of Species ◽  
South Wales ◽  
Physicochemical Factors ◽  
Number Of Individuals

Temporal patterns in number of species, number of individual animals and community composition of the soft-sediment zoobenthos of the Hawkesbury estuary are described and related to physicochemical factors. Replicate grabs were taken at 3-month intervals over 3 years (1977-1979) from sites located in three zones: the lower, middle and upper reaches. The number of species and number of individuals showed significant seasonal and annual differences in all zones. However, the pattern of these differences varied among sites and seasonal differences were not repeatable over years. Similarly, differences in community composition as revealed by classification were not seasonal. In the middle and lower reaches, these differences were apparently caused by the over- riding influence of non-seasonal climatic events, i.e. a major flood in 1978 and a drought throughout 1979. In the first two sampling following the flood, sample values for the numbers of both species and individuals were usually lowest and community composition was distinct from pre-flood and drought times. During the drought, the number of species was usually high and community composition relatively distinct. Whereas the number of species and community composition groupings were both significantly related to river discharge, the number of individuals was significantly correlated with temperature. All community variables were sometimes significantly related to salinity. The identity of numerically dominant species, as determined by Fager rankings, varied among times in both the lower and middle reaches. However, the polychaete Nephtys australiensis and the bivalve mollusc Notospisula trigonella were highest ranked overall in both zones. Community patterns in the low-salinity upper reaches differed from those further downstream by showing little change in numbers of species and community composition following the flood. Only the number of species was significantly correlated with any of the measured physicochemical variables, this being partly due to an influx of species during the drought. Furthermore, the upstream community was always dominated by the polychaete Ceratonereis limnetica and was thus the only community that could be characterised by a single species.

Mapping Physical Characteristics of the Columbia River Mouth Using Transmittered Diving Waterbirds

2013 ◽  
Author(s):  
Daniel D. Roby ◽  
Donald E. Lyons ◽  
Adam Peck-Richardson ◽  
James A. Lerczak
Keyword(s):  
River Mouth ◽  
Columbia River ◽  
Physical Characteristics

Field and Numerical Study of the Columbia River Mouth

2013 ◽  
Author(s):  
Guy Gelfenbaum ◽  
Jamie MacMahan ◽  
Ad Reniers
Keyword(s):  
Numerical Study ◽  
River Mouth ◽  
Columbia River

scholarly journals A check list of the spider fauna of the Karoo National Park, South Africa (Arachnida: Araneae)

Koedoe ◽  
1999 ◽  
Vol 42 (1) ◽  
Author(s):  
Anna S. Dippenaar-Schoeman ◽  
Astri Leroy ◽  
Marie De Jager ◽  
Annette Van den Berg
Keyword(s):  
South Africa ◽  
South African ◽  
National Survey ◽  
Habitat Preference ◽  
National Park ◽  
Single Species ◽  
Check List ◽  
The South ◽  
Spider Species ◽  
Number Of Species

A check list of the spider species of the Karoo National Park collected over a period of 10 years is presented. Thirty-eight families, represented by 102 genera and 116 species have been collected. Of these species, 76 (66.4 ) were wanderers and 39 (33.6 ) web builders. The Araneidae have the highest number of species (14) followed by the Thomisidae (10) and the Gnaphosidae (8), while 14 families are represented by a single species. Information on spider guilds, their habitat preference and web types is provided. This study forms part of the South African National Survey of Arachnida (SANSA).

Effect of Temperature on Butterfly Community (lepidoptera) at Gunung Meja Recreational Forest Area, Manokwari, Papua Barat

2016 ◽  
Vol 1 (1) ◽  
Author(s):  
Rawati Panjaitan
Keyword(s):  
Secondary Forest ◽  
Environmental Parameters ◽  
Forest Area ◽  
Effect Of Temperature ◽  
Species Number ◽  
Primary Forest ◽  
Residential Areas ◽  
Number Of Species ◽  
Butterfly Community ◽  
The Impact

<p>Gunung Meja is one of the forest areas in Manokwari, West Papua province. It has been designated as a recreational forest since 1980. Gunung Meja covers 460.25 ha and is located at 75–175 m a.s.l. Gunung Meja is directly adjacent to residential areas, therefore the community activities, such as felling trees and gardening, was conducted in the area frequently. These can interfered the existence of flora and fauna in the area, included butterflies. To reveal the impact of intrusive human activities on the forest area, it was necessary to obtain basic information about what flora and fauna are present there. This study was aim to record the butterfly community in the area. Observations of butterflies were done by scan sampling on primary forest, secondary forest, gardens and settlements. Sampling and measurement of environmental parameters were performed in the morning and afternoon for seven weeks. This study recorded 113 species and 4.049 individuals of butterflies. There were 75 species in primary forest, 77 species in secondary forest, and 63 species in gardens and settlements. The number of species found was still increasing until the last day of the observation. Shannon-Wiener index (H’) calculation showed that diversity in primary and secondary forests were 3.48 and 3.50, respectively, thus classified as high (H’ &gt; 3). Sorensen index calculation (C<em><sub>N</sub></em>) showed high value reaching 0.5 quantitatively. The numbers of butterflies both species number and individual number, observed in the morning were higher than those in the afternoon. There was significant effect (P &lt; 0.05) of temperature on the number of individual butterflies. The result of PCA analysis showed that the environmental parameters in primary forest, secondary forest, gardens and settlements influenced the number of species and number of individuals.</p>

scholarly journals FORECASTING THE WAVE-CURRENT INTERACTIONS AT THE MOUTH OF THE COLUMBIA RIVER, OR, USA

2012 ◽  
Vol 1 (33) ◽  
pp. 53 ◽  
Author(s):  
Sarah Kassem ◽  
H. Tuba Ozkan-Haller
Keyword(s):  
Pacific Northwest ◽  
Mean Squared Error ◽  
River Mouth ◽  
Columbia River ◽  
Tidal Currents ◽  
General Effect ◽  
The Pacific ◽  
Wave Forecast ◽  
Channel Wave ◽  
Wave Heights

An operational wave forecast of the area near the mouth of the Columbia River is presented. This region is known for its large waves and strong tidal currents. The forecast is forced with full directional spectra obtained from a refined WaveWatchIII forecast of the Pacific Northwest, and tidal current inputs are obtained from an estuarine circulation forecast of the Columbia River. The forecast has been operational since August 2011 providing short-term predictive wave information at the mouth of the Columbia River. Results from a 6-month period are promising, with a normalized root-mean-squared error (NRMSE) of 16% at the location of an inshore buoy, which is located outside the zone of tidal influence in 25 m water depth. Near the river mouth and in the channel, wave heights are heavily dominated by the tidal currents which significantly increase wave heights on ebb tides. Hindcast results shows that the model is able to predict the general effect of the tidal currents with a NRMSE of 30% in wave heights at the river mouth. Despite some of the model limitations, it still provides valuable information to navigators and bar pilots since it includes the effects of the tidal currents.

scholarly journals Komunitas Gastropoda Mangrove di Sungai Perpat dan Bunting, Kecamatan Belinyu, Kabupaten Bangka

2021 ◽  
Vol 6 (2) ◽  
pp. 85
Author(s):  
Eka Yuliawati ◽  
Budi Afriyansyah ◽  
Nova Mujiono
Keyword(s):  
Species Composition ◽  
Environmental Change ◽  
Dominant Species ◽  
Mangrove Ecosystem ◽  
Species Number ◽  
Mangrove Area ◽  
Number Of Species ◽  
Mangrove Ecosystems ◽  
Number Of Individuals

<strong>Mangrove gastropod community in Perpat and Bunting Rivers, Belinyu District, Bangka Regency</strong>. Perpat and Bunting in Bangka Regency have an adequate and natural mangrove ecosystems. However, studies on the structure of the gastropod community in this ecosystem is lacking. This study aimed to discover the structure of the gastropod community in the mangrove ecosystem. This study was carried out from October to November 2019 in riverine mangrove area located in Perpat and Bunting Rivers, District Belinyu, Bangka Regency. Samples were taken from 10 x 10 m plot from six observed stations. A total of 578 individuals of gastropoda were collected, comprised of seven families and 14 species. Number of species ranged from 4 to 9, while number of individuals ranged from 35 to 214. <em>Cerithidea quoyii</em> was a dominant species with 270 individuals (47%) and found in all stations. Gastropods community was in labile condition and prone to environmental change. Species composition of gastropods were similar in both rivers with nine identical species. However, epifaunal species were found separately from arboreal species

scholarly journals Distribution and diversity of Polyporaceae in Western India: An overview and addition to mycoflora of the Gujarat state

2018 ◽  
Vol 5 (1) ◽  
pp. 32-38 ◽  
Author(s):  
Ajit M Vasava ◽  
Ravi S Patel ◽  
Rina D Koyani ◽  
Kishore S. Rajput
Keyword(s):  
Single Species ◽  
Fungal Species ◽  
Western India ◽  
Gujarat State ◽  
Number Of Species ◽  
Dichomitus Squalens ◽  
Laetiporus Sulphureus ◽  
The Family ◽  
First Time ◽  
New Distribution

Extensive fieldwork in different climatic regimes of Gujarat state during last four years resulted in the collection of more than 349 fungal species. Out of these, 37 species from 20 genera were found to be from the family Polyporaceae. Among these, five species are being reported for the first time here as new distribution records. The highest number of species is represented by the genus Trametes while, Cerrena unicolo, Neolentinus kauffmanii, Dichomitus squalens, Panus conchatus and Laetiporus sulphureus possessed single species each.

scholarly journals Sampling principles for biodiversity study

2013 ◽  
Author(s):  
Xubin Pan
Keyword(s):  
Mathematical Expectation ◽  
Specific Area ◽  
Species Number ◽  
Basic Principles ◽  
Number Of Species ◽  
Individual Number ◽  
Species Area ◽  
Biodiversity Study ◽  
Number Of Individuals ◽  
Total Species

Sampling is a fundamental tool in ecology and critical for biodiversity measurement. However, basic principles of biodiversity sampling have been overlooked for many years. In this paper, I proposed and explored five principles of sampling for a specific area and biodiversity study. The first principle of sampling, species increasing with area, is that the number of species increases with the area. The second principle of sampling, individuals increasing with area, is that the number of individuals increases with the area. The third principle of sampling, sum of species number, is that the sum of species number in one area and species number in another area is no less than the total species number in the two areas. The fourth principle of sampling, individual complement, is that the sum of the mathematical expectation of individual number of one or several species in the area a and that of the same one or several species in the area A-a is the total individual number N of the same one or several species in the total area A. The fifth principle of sampling, species-area theory, is that the sum of the mathematical expectation of number of species in the area a and that of number of species lost if area A-a is cleared is the total species number M in the total area A.

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