Shifts in macrophyte species composition as a result of eutrophication and pollution in Dutch transboundary streams over the past decades

1995 ◽  
Vol 4 (4) ◽  
pp. 295-305 ◽  
Author(s):  
Carleen M. L. Mesters
Keyword(s):  
Species Composition ◽  
The Past ◽  
Macrophyte Species

scholarly journals Historical discarding in Mediterranean fisheries: a fishers' perception

2015 ◽  
Vol 72 (9) ◽  
pp. 2600-2608 ◽  
Author(s):  
Dimitrios Damalas ◽  
Christos D. Maravelias ◽  
Giacomo C. Osio ◽  
Francesc Maynou ◽  
Mario Sbrana ◽  
...  
Keyword(s):  
Species Composition ◽  
Market Demand ◽  
Sampling Protocol ◽  
The Past ◽  
Regulatory Constraints ◽  
Fishing Strategies ◽  
Commercially Important ◽  
Trawl Fisheries ◽  
Important Fish

Abstract Discarding of commercially important fish species in the bottom trawl fisheries in the northern Mediterranean Sea was investigated by soliciting the long-term recollections of fishers engaged or formerly engaged in such fisheries. The main aim of our investigation was to describe the prevalence of discarding and its evolution over the past 70 years using information gathered through individual questionnaire-based interviews with fishers from ports in Spain, Italy, and Greece, following a standardized sampling protocol. Although it proved impossible to derive absolute estimates of the volume of discarded catches over the period investigated, we conclude that over the past 70 years, discarding as a practice has gradually increased in the northern Mediterranean trawl fisheries and has been accompanied by a shift in the species composition of the discarded catch. While discarding can occur for a number of reasons, our investigations indicate that discarding in the past was mostly driven by market demand, but recent legal and regulatory constraints have led to changes in fishing strategies and became a significant reason for discards.

Effect of the Gabčíkovo Waterworks (Slovakia) on riparian floodplain forest ecosystems in the Danube inland delta: vegetation dynamics and trends

Biologia ◽  
2017 ◽  
Vol 72 (7) ◽  
Author(s):  
Mária Petrášová-Šibíková ◽  
Igor Matečný ◽  
Eva Uherčíková ◽  
Peter Pišút ◽  
Silvia Kubalová ◽  
...  
Keyword(s):  
Species Composition ◽  
Forest Ecosystems ◽  
Supply System ◽  
Floodplain Forest ◽  
Soil Conditions ◽  
Plant Species Composition ◽  
Forest Species ◽  
The Past ◽  
The Impact ◽  
Rare Opportunity

AbstractHuman alteration of watercourses is global phenomenon that has had significant impacts on local ecosystems and the services they provide. Monitoring of abiotic and biotic changes is essential to mitigating long-lasting effects, and the 23-year dataset from the Gabčíkovo Waterworks provided a rare opportunity to assess the impact of groundwater regimes on vegetation. The main aim of this study was to describe the effect of the Gabčíkovo Waterworks on vegetation structure and species composition of the adjacent riparian floodplain forests over the past 23 years. The results are based on studies of three permanent monitoring plots (PMPs) located in the Danube inland delta – two outside (PMP 1 and 3) and one (PMP 2) fully under the influence of the artificial supply system. Our results demonstrate that the Danube inland delta was negatively affected by the Gabčíkovo construction, particularly for sites outside of the artificial supply system. There was a significant decrease in soil moisture and increase in nitrogen at both external PMPs (1 and 3). Alter soil conditions were accompanied by negative changes in plant species composition demonstrated by decreases in the number of typical floodplain forest species that are characteristic for the alliance

Species composition of the Late Cretaceous eutherian mammal Paranyctoides Fox

2013 ◽  
Vol 50 (7) ◽  
pp. 693-700 ◽  
Author(s):  
Marisol Montellano-Ballesteros ◽  
Richard C. Fox ◽  
Craig S. Scott
Keyword(s):  
North America ◽  
Species Composition ◽  
Central Asia ◽  
Late Cretaceous ◽  
Geographic Range ◽  
Eutherian Mammal ◽  
The Past ◽  
Central Asian ◽  
Dinosaur Park Formation ◽  
Eutherian Evolution

Although the known record of Mesozoic eutherian mammals has been significantly enriched in recent years, early eutherian evolution is still not well understood. Among the more controversial of Mesozoic eutherians is Paranyctoides Fox, which was described in 1979 from the Judithian Dinosaur Park Formation, Alberta, Canada. It is a rare taxon and therefore has been identified in only a few other North American Late Cretaceous local faunas since. Within the past decade, dental and gnathic remains discovered in Central Asia have also been referred to Paranyctoides, thereby expanding the geographic range of the genus substantially and making it the only Late Cretaceous eutherian ostensibly occurring in both continents. As a result of our detailed study of Paranyctoides, however, we find that the Central Asian species lack the diagnostic characters of Paranyctoides and must be referred to other taxa. We conclude that this genus was limited to North America, ranging from Aquilan to Lancian time, and accordingly we recognize as valid only the following species: Paranyctoides sternbergi (Judithian, Alberta), P. maleficus (Aquilan, Alberta), Paranyctoides Wahweap sp. A and sp. B (Judithian, Utah), Paranyctoides Kaiparowits sp. A and sp. B (Judithian, Utah). Another purported species of Paranyctoides, P. megakeros, from the Lancian of Wyoming, is a junior synonym of Alostera saskatchewanensis.

Soot Activation Energy for a Xylene-Fueled CVD Reactor

2007 ◽  
Vol 5 (1) ◽  
Author(s):  
Wahed Wasel ◽  
Kazunori Kuwana ◽  
Kozo Saito
Keyword(s):  
Activation Energy ◽  
Carbon Nanotube ◽  
Species Composition ◽  
Gas Phase ◽  
Inverse Method ◽  
Soot Formation ◽  
Effect Of Temperature ◽  
Gas Phase Reactions ◽  
Concentration Data ◽  
The Past

The past attempts of Arrhenius plots of carbon nanotube (CNT) yield (or CNT length) to obtain the overall activation energy for CNT formation under changing reaction temperature conditions have created substantial errors. Here we propose an inverse method to accurately account for the effect of temperature on gas-phase reactions and species composition. The overall activation energy of soot formation for a xylene-based CVD reactor was calculated and successfully compared with the measured gas-phase concentration data. Our proposed inverse method is expected to help improve the performance of CVD reactors and optimize its design.

scholarly journals Updated distribution and species composition of the amphibians and reptiles along the Lower Danube, Bulgaria

2019 ◽  
Vol 2 ◽  
Author(s):  
Georgi Popgeorgiev ◽  
Borislav Naumov ◽  
Yurii Kornilev ◽  
Vladislav Vergilov ◽  
Miroslav Slavchev ◽  
...  
Keyword(s):  
Species Composition ◽  
Native Species ◽  
Economic Incentives ◽  
Danube River ◽  
The Past ◽  
First Time ◽  
Published Paper

In a recently published paper (Popgeorgiev et al. 2019), we compiled for the first time published and unpublished data on localities of the herpetofaunal species observed up to ca. 10 km south of the Bulgarian Danube River. Overall, we identified 687 published records belonging to 62 cells of the 10×10 km MGRS grid. Another 1918 records with real coordinates of our unpublished data from the past ca. 13 years belong to 1269 cells of the 1×1 MGRS grid. As a result, 34 native species – 15 amphibians (4 salamanders and 11 frogs) and 19 reptiles (1 turtle, 2 tortoises, 8 lizards and 8 snakes), and one invasive turtle, have been recorded; further species findings are unlikely. This study further identifies areas that are under-sampled and species such as Pelophylax lessonae that are cryptic. Our data are especially relevant concerning the high economic incentives to change the hydrology of the Danube, which will likely negatively impact the biodiversity along the river and its surrounding.

scholarly journals Butterflies of Amazon and Cerrado remnants of Maranhão, Northeast Brazil

2017 ◽  
Vol 17 (3) ◽  
Author(s):  
Lucas Pereira Martins ◽  
Elias da Costa Araujo Junior ◽  
Ananda Regina Pereira Martins ◽  
Mairla Santos Colins ◽  
Gabriela Cristina Fonseca Almeida ◽  
...  
Keyword(s):  
Species Composition ◽  
Sampling Methods ◽  
Biological Indicator ◽  
The State ◽  
Small Subset ◽  
Northeast Brazil ◽  
The Past ◽  
Local Diversity ◽  
Baited Traps

Abstract Species inventories are important tools to evaluate biodiversity losses and contribute to the conservation of endangered areas. The Amazon and Cerrado are the largest Brazilian biomes and represent some of the most threatened regions of the country. Due to its location between these biomes, the state of Maranhão, Northeast Brazil, possesses a great variety of habitats and a high local diversity. Nonetheless, few faunistic inventories of diversified groups have been performed in the state. In the specific case of butterflies, a well-known biological indicator, no inventories have been published in the past years. This study aimed to expand the knowledge on the composition of butterflies in Amazon and Cerrado remnants of Maranhão. Butterflies were sampled between 2011 and 2015 across eight municipalities of the state. Captures were made through entomological nets and baited traps. In total, 189 species were sampled, of which 165 were captured in the Amazon, 65 in the Cerrado and 41 in both biomes. We sampled 167 species through entomological nets and 43 through baited traps, representing 12% of similarity in species composition between sampling methods. We estimate that the recorded species represent a small subset of the butterflies from Maranhão. Therefore, long-term researches in poorly studied areas of the state are recommended to identify novel and/or endemic taxa.

scholarly journals Changes of avifauna in green areas of Almaty City in the beginning of 21st century

2021 ◽  
Vol 265 ◽  
pp. 01002
Author(s):  
Viktoriya Ilina ◽  
Roman Jashenko ◽  
Tastybai Meruert ◽  
Geidt Assya
Keyword(s):  
Species Composition ◽  
21St Century ◽  
Bird Species ◽  
The Past ◽  
Green Areas ◽  
Fundamental Research ◽  
In The Beginning ◽  
The City ◽  
Urban Fauna

Currently, there are serious changes in the environment in Almaty due to the accentuated urbanization processes. The avifauna of the city is experiencing serious stress pressure in this regard, which forces the animals to adapt to new conditions or leave this territory. The last fundamental research on the species composition of the city's fauna was conducted about 3 decades ago. The analysis of information on the birds of Almaty, collected by specialists of the Institute of Zoology over the past 50 years, showed significant changes in the avifauna. 5 categories of bird species were identified: 1) species that have disappeared from the urban fauna, 2) species whose numbers have declined significantly, 3) species that have a tendency to decline in numbers, 4) species whose numbers are stable or have increased, 5) species that are settling.

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