Hyperiid amphipod vertical distribution and community structure in the upper 100 m of the northwestern Caribbean Sea

The community structure and variability of the hyperiid amphipods of the Northwestern Tropical Atlantic (NWTA) remain largely unknown. We described and analyzed the hyperiid nictemeral, vertical, and horizontal distribution and the influence of environmental variables in the upper 100 m of the northwestern Caribbean Sea. We examined 196 zooplankton samples obtained during both day and nighttime at four depth strata from 49 sampling stations in January 2007. Up to 82 hyperiid species including 14 new regional records were identified and quantified. Both day/night and some interstrata differences were significant, particularly in reference to the uppermost and deepest strata. The local hyperiid community structure appeared to be profiled by the frequency and abundance variations of the two most abundant species, Lestrigonus bengalensis and Brachyscelus crusculum, both being most abundant in the uppermost (0–25 m) stratum. The horizontal distribution of the highest hyperiid abundance and diversity appears to be related to the influence of mesoscale processes like upwelling and cyclonic eddies. The Gulf of Honduras area had relatively low hyperiid abundances. The principal component analysis revealed density and temperature as the main factors explaining the local environmental variability. The canonical analysis of principal coordinates (CAP) showed that salinity and temperature strongly influenced the variability of the local hyperiid community. Overall, the two middle vertical strata (25–75 m) were relatively uniform; the main differences were found only between the uppermost and deepest strata. This study is the first to provide information regarding small-scale vertical distribution of hyperiid amphipods in the NWTA.

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Heavy Metal Distribution and Sources in Pineapple-Growing Agricultural Soil in Hainan Province, China

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.955-959.1003 ◽

2014 ◽

Vol 955-959 ◽

pp. 1003-1008

Author(s):

Zhen Zhen Ma ◽

Yu Guo ◽

Zheng Yu Bao ◽

Guo Ai Wu ◽

Yang Rong Fu

Keyword(s):

Heavy Metal ◽

Vertical Distribution ◽

Agricultural Soil ◽

Principal Component ◽

Horizontal Distribution ◽

Parent Material ◽

Hainan Province ◽

Soil Parent Material ◽

The Vertical Distribution

An investigation on heavy metal content in agricultural soil growing pineapples was carried out in Hainan Province. The horizontal and vertical distribution of heavy metal in different areas was studied. The sources of heavy metal were conducted using principal component analysis. Generally the study areas were less affected by human activity factors and the overall environmental quality was quite better. The uneven horizontal distribution of heavy metal was controlled mainly by the soil parent material and the vertical distribution of heavy metal was limited by both the role of human activities and the natural effect combined.

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Recovery of ciliated protozoan communities in response to environmental change in a shrimp-farming pond in southern China

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315417000315 ◽

2017 ◽

Vol 98 (6) ◽

pp. 1263-1272 ◽

Cited By ~ 2

Author(s):

Qian Liu ◽

Borong Lu ◽

Xue Song ◽

Yan Li ◽

Yu Gao ◽

...

Keyword(s):

Community Structure ◽

Temporal Dynamics ◽

Southern China ◽

Abundant Species ◽

Shrimp Farming ◽

Ciliate Community ◽

Chinese Shrimp ◽

Southern Chinese ◽

Principal Coordinates ◽

Cap Analysis

The temporal dynamics of ciliate community structure in a southern Chinese shrimp aquaculture facility were investigated during the period June–September 2012. A total of 53 species belonging to 37 genera and 17 orders were recorded based on analyses of eight samples. Ciliate abundance peaked between 16 August and 14 September 2012, while the maximum number of species occurred on 26 June 2012. Clear temporal patterns were observed in the ciliate community structure. The patterns of succession of the 10 most abundant species were consistent with the results of a Canonical Analysis of Principal coordinates (CAP) analysis. Correlation analyses showed that these patterns of succession were related to temporal changes in environmental variables. In summary, the results demonstrate that the ciliate community responds predictably to environmental variations and recovers from shrimp cultivation.

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Patterns Of Biodiversity In The Macro-Invertebrate Fauna Associated With Mussel Patches On Rocky Shores

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315400029131 ◽

1996 ◽

Vol 76 (1) ◽

pp. 203-210 ◽

Cited By ~ 90

Author(s):

Raymond Seed

Keyword(s):

Species Richness ◽

Abundant Species ◽

Small Scale ◽

Marine Biodiversity ◽

Rocky Shores ◽

Invertebrate Fauna ◽

Marine Mussels ◽

High Species Richness ◽

Global Patterns ◽

Abundance And Diversity

Marine mussels are widely distributed and have been used extensively as environmental biomonitors. Communities associated with mussel patches have a high species richness but are typically dominated by a few very abundant species. These communities exhibit significant temporal and small-scale spatial variations in abundance and diversity which should be recognized when considering global patterns of marine biodiversity. Many of the species associated with tropical mussel beds are also represented by taxonomically and functionally equivalent species in mussel communities from temperate waters. The phenomenon of ‘parallel communities’ on rocky shores is thus apparently replicated on a finer spatial scale within mussel patches.

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Vertical Distribution Relations for Special Cycles on Unitary Shimura Varieties

International Mathematics Research Notices ◽

10.1093/imrn/rny119 ◽

2018 ◽

Vol 2020 (13) ◽

pp. 3902-3926

Author(s):

Réda Boumasmoud ◽

Ernest Hunter Brooks ◽

Dimitar P Jetchev

Keyword(s):

Vertical Distribution ◽

Three Dimensional ◽

Complex Multiplication ◽

Horizontal Distribution ◽

Unitary Groups ◽

Shimura Varieties ◽

Heegner Points ◽

Universal Norm

Abstract We consider cycles on three-dimensional Shimura varieties attached to unitary groups, defined over extensions of a complex multiplication (CM) field $E$, which appear in the context of the conjectures of Gan et al. [6]. We establish a vertical distribution relation for these cycles over an anticyclotomic extension of $E$, complementing the horizontal distribution relation of [8], and use this to define a family of norm-compatible cycles over these fields, thus obtaining a universal norm construction similar to the Heegner $\Lambda $-module constructed from Heegner points.

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Effects of Land-Use Change on the Community Structure of the Dung Beetle (Scarabaeinae) in an Altered Ecosystem in Southern Ecuador

Insects ◽

10.3390/insects12040306 ◽

2021 ◽

Vol 12 (4) ◽

pp. 306

Author(s):

Vinicio Carrión-Paladines ◽

Andreas Fries ◽

Andrés Muñoz ◽

Eddy Castillo ◽

Roberto García-Ruiz ◽

...

Keyword(s):

Land Use ◽

Community Structure ◽

Land Use Change ◽

Dung Beetle ◽

Dry Forest ◽

Farm Animals ◽

P Value ◽

Southern Ecuador ◽

Abundance And Diversity ◽

Effects Of Land Use

This study evaluated the effects of land-use change (L-UCH) on dung beetle community structure (Scarabaeinae) in a disturbed dry ecosystem in southern Ecuador. Five different L-UCH classes were analyzed by capturing the dung beetle species at each site using 120 pitfall traps in total. To determine dung beetle abundance and diversity at each L-UCH, a general linear model (GLM) and a redundancy analysis (RDA) were applied, which correlated environmental and edaphic conditions to the community structure. Furthermore, changes in dung-producing vertebrate fauna were examined, which varied significantly between the different L-UCH classes due to the specific anthropogenic use or level of ecosystem disturbance. The results indicated that soil organic matter, pH, potassium, and phosphorus (RDA: component 1), as well as temperature and altitude (RDA: component 2) significantly affect the abundance of beetles (GLM: p value < 0.001), besides the food availability (dung). The highest abundance and diversity (Simpson’s index > 0.4, Shannon-Wiener index > 1.10) was found in highly disturbed sites, where soils were generally more compacted, but with a greater food supply due to the introduced farm animals. At highly disturbed sites, the species Canthon balteatus, Dichotomius problematicus, and Onthphagus confuses were found specifically, which makes them useful as bio-indicators for disturbed dry forest ecosystems in southern Ecuador.

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Using a Groundwater Adjusted Water Balance Approach and Copulas to Evaluate Spatial Patterns and Dependence Structures in Remote Sensing Derived Evapotranspiration Products

Remote Sensing ◽

10.3390/rs13050853 ◽

2021 ◽

Vol 13 (5) ◽

pp. 853

Author(s):

Mohsen Soltani ◽

Julian Koch ◽

Simon Stisen

Keyword(s):

Remote Sensing ◽

Water Balance ◽

Spatial Pattern ◽

Spatial Patterns ◽

Principal Component ◽

Small Scale ◽

Dependence Structure ◽

Test Case ◽

Catchment Scale ◽

Balance Approach

This study aims to improve the standard water balance evapotranspiration (WB ET) estimate, which is typically used as benchmark data for catchment-scale ET estimation, by accounting for net intercatchment groundwater flow in the ET calculation. Using the modified WB ET approach, we examine errors and shortcomings associated with the long-term annual mean (2002–2014) spatial patterns of three remote-sensing (RS) MODIS-based ET products from MODIS16, PML_V2, and TSEB algorithms at 1 km spatial resolution over Denmark, as a test case for small-scale, energy-limited regions. Our results indicate that the novel approach of adding groundwater net in water balance ET calculation results in a more trustworthy ET spatial pattern. This is especially relevant for smaller catchments where groundwater net can be a significant component of the catchment water balance. Nevertheless, large discrepancies are observed both amongst RS ET datasets and compared to modified water balance ET spatial pattern at the national scale; however, catchment-scale analysis highlights that difference in RS ET and WB ET decreases with increasing catchment size and that 90%, 87%, and 93% of all catchments have ∆ET < ±150 mm/year for MODIS16, PML_V2, and TSEB, respectively. In addition, Copula approach captures a nonlinear structure of the joint relationship with multiple densities amongst the RS/WB ET products, showing a complex dependence structure (correlation); however, among the three RS ET datasets, MODIS16 ET shows a closer spatial pattern to the modified WB ET, as identified by a principal component analysis also. This study will help improve the water balance approach by the addition of groundwater net in the ET estimation and contribute to better understand the true correlations amongst RS/WB ET products especially over energy-limited environments.

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Community structure and vertical distribution of planktonic ciliates in the saline meromictic lake Shira during breakdown of meromixis

Ecohydrology & Hydrobiology ◽

10.1016/j.ecohyd.2020.08.001 ◽

2020 ◽

Author(s):

Elena B. Khromechek ◽

Yuri V. Barkhatov ◽

Denis Y. Rogozin

Keyword(s):

Community Structure ◽

Vertical Distribution ◽

Meromictic Lake ◽

Planktonic Ciliates ◽

Lake Shira

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Temporal and spatial variability in the community structure of the fauna of four sandy beaches in south-eastern New South Wales.

Marine and Freshwater Research ◽

10.1071/mf9840663 ◽

1984 ◽

Vol 35 (6) ◽

pp. 663 ◽

Cited By ~ 46

Author(s):

DM Dexter

Keyword(s):

Community Structure ◽

Diversity Index ◽

Abundant Species ◽

Sandy Beaches ◽

Sampling Procedure ◽

Wave Action ◽

Physical Factors ◽

Faunal Composition ◽

South Wales ◽

Temporal And Spatial

Four intertidal sandy beaches with different exposures, La Perouse, Ocean Beach, Dolls Point, and Towra Point, were studied for temporal and spatial changes in faunal composition and community structure. Each of these beaches was sampled from 6 to 12 times between July 1980 and July 1981 using a 500 �m sieve. A stratified random sampling procedure across the intertidal zone isolated 40 660 individuals representing 85 species. Distribution and abundance of species were strongly influenced by tidal level. Densities changed during the year but no seasonal changes in intertidal zonation patterns were found. Changes in density were correlated with the reproductive activities of the abundant species, especially Pseudolana concinna and Exoediceros maculosus at La Perouse, and Spio pacifica at Dolls Point and Towra Point. The number of species increased from high to low tide, and also increased with decreasing exposure to wave action. Crustaceans dominated the fauna in the most exposed site and decreased in abundance with increasing protection. Ocean Beach experienced the least fluctuation in physical factors such as wave action, salinity, and temperature, and its fauna exhibited the highest diversity index (H') and evenness (J'), the most stable density, and the greatest stability in faunal composition through time. The highest densities and the most species were found at Towra Point, which also was the most protected site.

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