Effects of Phosphorus on Benthic Diatom Assemblage Network Structure

Nuisance Didymosphenia geminata (Lyngbye) M. Schmidt (didymo) blooms were first reported in 2006 from the Restigouche River Watershed (RRW), eastern Canada. Although government agencies and recreational users are concerned about these blooms, little is known about the impact on biota and (or) the structure and function of the relatively pristine riverine systems of the RRW. Here, we assess whether didymo blooms affect overall benthic diatom assemblage composition by examining epilithic samples from middle stretches of the Patapedia and Upsalquitch rivers. Significant (albeit minor) differences (P < 0.05) in diatom assemblage composition between sites, with and without didymo blooms, were only observed from the Patapedia River. Rarefied diatom species diversity (Hill’s N2) and rarefied richness did not differ significantly among sites, regardless of the presence or absence of blooms. Our data show that didymo blooms have minimal effect on benthic diatom assemblage composition in the RRW.

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How do abiotic environmental variables shape benthic diatom assemblages in subtropical streams?

Marine and Freshwater Research ◽

10.1071/mf15388 ◽

2017 ◽

Vol 68 (5) ◽

pp. 863 ◽

Cited By ~ 4

Author(s):

Wing Ying Tsoi ◽

Wade L. Hadwen ◽

F. Sheldon

Keyword(s):

Environmental Gradients ◽

Critical Role ◽

Benthic Diatom ◽

Base Flow ◽

Diatom Assemblage ◽

Environmental Drivers ◽

Diatom Assemblages ◽

Physical And Chemical Variables ◽

Ecological Importance ◽

Physical And Chemical

Diatoms (Division Bacillariophyta) commonly dominate benthic algal communities in upland streams and are the major primary producers that sit at the base of food webs. Given their ecological importance, the aim of the present study was to investigate the spatial patterns of freshwater biofilm biomass and diatom assemblage composition in response to differences in physical and chemical variables in the Bremer, Logan and Albert catchments in south-east Queensland. Patterns in benthic diatom assemblage structure were examined during base flow conditions and the focus was on relating the spatial hierarchical interrelationships among ultimate (i.e. catchments and geology) and proximate (i.e. flow, nutrients, light, conductivity, pH and turbidity) environmental drivers. The spatial difference observed in the benthic diatom assemblages was predominantly driven by proximate environmental drivers, which, in turn, were affected by ultimate drivers. Flow played a critical role in controlling both biofilm biomass and affecting the occurrence of diatom taxa. Nutrients and light also played roles as limiting resources structuring biofilm biomass and the relative abundance of diatoms. Diatom growth form, cell size and attachment mode can be used to create a more quantitative and predictive approach to establishing relationships between diatoms and environmental gradients.

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Flood disturbance effects on benthic diatom assemblage structure in a semiarid river network

Journal of Phycology ◽

10.1111/jpy.12260 ◽

2015 ◽

Vol 51 (1) ◽

pp. 133-143 ◽

Cited By ~ 5

Author(s):

Elisabet Tornés ◽

Vicenç Acuña ◽

Clifford N. Dahm ◽

Sergi Sabater

Keyword(s):

River Network ◽

Assemblage Structure ◽

Benthic Diatom ◽

Diatom Assemblage ◽

Flood Disturbance ◽

Disturbance Effects

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An alter-centric perspective on employee innovation: The importance of alters’ creative self-efficacy and network structure.

Journal of Applied Psychology ◽

10.1037/apl0000220 ◽

2017 ◽

Vol 102 (9) ◽

pp. 1360-1374 ◽

Cited By ~ 20

Author(s):

Travis J. Grosser ◽

Vijaya Venkataramani ◽

Giuseppe (Joe) Labianca

Keyword(s):

Network Structure ◽

Self Efficacy ◽

Creative Self

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Türkiye'de iller arası göçlerin nodexl ile sosyal ağ analizi

GÖÇ DERGİSİ ◽

10.33182/gd.v4i1.573 ◽

2017 ◽

Vol 4 (1) ◽

pp. 82-109 ◽

Cited By ~ 1

Author(s):

Mustafa Yakar ◽

Fatma Sert Eteman

Keyword(s):

Network Structure ◽

Population Data ◽

Single Mode ◽

Turkish Population ◽

Place Of Birth ◽

Place Of Residence ◽

Migration Flow ◽

Population Structures ◽

The Republic ◽

Provincial Scale

Türkiye'de 20.yy'ın ortasından itibaren başlayan iç göçler zamanla kurulan göçmen ağları ile süreklilik kazanmış ve ülke içinde nüfusun kır-kent dağılımını değiştirecek boyutlara erişmiştir. Araştırma, göçün doğum yeri verisinden hareketle ikamet edilen yerdeki nüfus miktarına göre alınan ve verilen göç akışının büyüklüğünü iller ölçeğinde yönlü ağlar kullanılarak analiz edilmesini amaçlamaktadır. Araştırmada, TÜİK tarafından yayınlanmış olan 2015 yılına ait, iller ölçeğinde doğum yerine göre ikamet yeri verisi kullanılmıştır. Göçün kaynak ve hedef sahaları arasındaki akışını incelemek için NodeXL ile oluşturulan tek modlu, yönlü ve ağırlıklandırılmış göç ağının istatistiksel olarak tam ağ yapısına sahip olduğu görülmüştür. Ağ grafiklerinden ve istatistiklerinden göç hareketinin doğudan batıya doğru gerçekleştiği ve İstanbul’ un ülkenin tamamına hâkim bir görünüme sahip olduğu anlaşılmaktadır. Türkiye nüfusunun cumhuriyet tarihi içinde geçirdiği iç göç süreçleriyle birlikte ülke içinde kurulmuş ve oldukça karmaşık bir görünüme sahip ağ yapısının olduğu ileri sürülebilir. Kurulan ağlar göçlerin devamını sağladığı gibi, göçün yöneldiği merkezlerde daha heterojen nüfus yapılarının ortaya çıkmasına yol açmıştır.ABSTRACT IN ENGLISHSocial Network Analysis of Migration Inter Provinces In Turkey with Nodexl The internal migrations which started in Turkey in the middle of the 20th century have gained permanency with the migration networks that were established at the time and reached dimensions which have the potential to change the rural-urban distribution of the population within the country. The study aims to analyze the magnitude of the incoming and outgoing migration flow at the provincial scale based on the population data for place of birth according to place of residence by using directional networks. Place of residence according to place of birth at the provincial scale data for 2015 published by TÜİK was used in the study. A single mode, directional and weighted migration network created with NodeXL to examine the migration flows between the source and target has a statistically complete network structure. The network graphs and statistics show that the migrations have taken place from east to west and Istanbul has a view as dominant of the country. It can be argued that internal network structure of Turkish population has a very complex view because of internal migration in the history of the republic. The established networks have enabled the continuation of migration and have manifested as the emergence of more heterogeneous population structures in centers where migration had been directed.

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Application of Fractal Methods to Ensure the Cyber-Resilience of Self-Organizing Networks

Nonlinear Phenomena in Complex Systems ◽

10.33581/1561-4085-2019-22-4-336-341 ◽

2019 ◽

Vol 22 (4) ◽

pp. 336-341

Author(s):

D. V. Ivanov ◽

D. A. Moskvin

Keyword(s):

Information Security ◽

Network Structure ◽

Self Regulation ◽

Security Threats ◽

Self Organizing Networks ◽

Self Organizing ◽

Fractal Methods

In the article the approach and methods of ensuring the security of VANET-networks based on automated counteraction to information security threats through self-regulation of the network structure using the theory of fractal graphs is provided.

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