scholarly journals How and to What Degree Does Physical Structure Differ Between Natural and Artificial Habitats? A Multi-Scale Assessment in Marine Intertidal Systems

2021 ◽  
Vol 8 ◽  
Author(s):  
Ferrante Grasselli ◽  
Laura Airoldi
Keyword(s):  
Construction Material ◽  
Structural Complexity ◽  
Physical Structure ◽  
Physical Habitat ◽  
Ecological Value ◽  
Natural Habitats ◽  
Artificial Habitats ◽  
The North ◽  
Ecological Consideration ◽  
Abundance And Diversity

Marine infrastructures are increasing, generating a variety of impacts and introducing artificial habitats which have low ecological value and support assemblages that differ significantly from those on natural rocky coasts. While in the past there was little ecological consideration as to how artificial structures were built, now the trend is to look for “greener” designs inspired by or mimicking nature. These greening efforts have had a strong focus on enhancing physical habitat structure to support more diverse assemblages, driven by the untested assumption that artificial habitats lack the physical structure proper to natural habitats. We tested this assumption by comparing five descriptors of physical structure (inclination; exposure; roughness; abundance, and diversity of surface morphological microelements) across a combination of natural and artificial habitats of regular and irregular morphologies (seawalls = artificial regular; cliffs = natural regular; breakwaters = artificial, irregular; and boulder fields = natural irregular) in the North Adriatic Sea. Most structural descriptors were similar between artificial and natural habitats. Only inclination was consistently steeper in the artificial than in the natural habitats. Other minor differences in roughness or in the abundance of some surface microelements were related to the general morphology (regular or irregular) of the habitat rather than to its artificial or natural identity. The outcomes challenge the widespread assumption that artificial habitats lack the physical structure proper to natural habitats and stimulate renewed consideration about other structural and non-structural elements that could enhance the performance and sustainability of artificial marine structures, such as construction material, environmental setting or maintenance. They also encourage a wider reflection about what makes an artificial building surface “greener”: structural complexity is an important ecological parameter, and its deliberate increase will lead to responses in the biota, however, this may not necessarily match “more natural” conditions.

scholarly journals Dynamics of Stone Habitats in Coastal Waters of the Southwestern Baltic Sea (Hohwacht Bay)

Geosciences ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 171
Author(s):  
Gitta Ann von Rönn ◽  
Knut Krämer ◽  
Markus Franz ◽  
Klaus Schwarzer ◽  
Hans-Christian Reimers ◽  
...  
Keyword(s):  
Baltic Sea ◽  
Physical Structure ◽  
Glacial Till ◽  
Dynamic Processes ◽  
Physical Habitat ◽  
Ecological Value ◽  
Large Bandwidth ◽  
Sediment Types ◽  
Dynamic Type ◽  
Wave Induced

Cobbles and boulders on the seafloor are of high ecological value in their function as habitats for a variety of benthic species, contributing to biodiversity and productivity in marine environments. We investigate the origin, physical shape, and structure of habitat-forming cobbles and boulders and reflect on their dynamics in coastal environments of the southwestern Baltic Sea. Stone habitats are not limited to lag deposits and cannot be sufficiently described as static environments, as different dynamic processes lead to changes within the physical habitat structure and create new habitats in spatially disparate areas. Dynamic processes such as (a) ongoing exposure of cobbles and boulders from glacial till, (b) continuous overturning of cobbles, and (c) the migration of cobbles need to be considered. A distinction between allochthonous and autochthonous habitats is suggested. The genesis of sediment types indicates that stone habitats are restricted to their source (glacial till), but hydrodynamic processes induce a redistribution of individual cobbles, leading to the development of new coastal habitats. Thus, coastal stone habitats need to be regarded as dynamic and are changing on a large bandwidth of timescales. In general, wave-induced processes changing the physical structure of these habitats do not occur separately but rather act simultaneously, leading to a dynamic type of habitat.

Parasite commonality at Swamp Deer (Mammalia: Artiodactyla: Cervidae: Rucervus duvaucelii duvaucelii) and livestock interface

2020 ◽  
Vol 12 (3) ◽  
pp. 15364-15369
Author(s):  
Animesh Talukdar ◽  
Bivash Pandav ◽  
Parag Nigam
Keyword(s):  
Intestinal Parasites ◽  
Uttar Pradesh ◽  
Anthropogenic Pressure ◽  
Wildlife Sanctuary ◽  
Natural Habitats ◽  
Coprological Examination ◽  
Parasitic Load ◽  
Abundance And Diversity ◽  
Swamp Deer ◽  
Different Levels

Interactions between wildlife and livestock have increased over time with increased anthropogenic pressure on limited available natural habitats.  These interactions have resulted in sharing of pathogens between the species resulting in impacting the wild animals’ fitness and reproduction and further influencing their abundance and diversity.  The spatial overlap between Swamp Deer and livestock was studied at Jhilmil Jheel Conservation Reserve (JJCR), Uttarakhand and Kishanpur Wildlife Sanctuary (KWLS), Uttar Pradesh in India, having different levels of interaction with livestock.  The prevalence, load and commonality of gastro-intestinal parasites in the species was studied through coprological examination. Parasitic ova of Strongyle sp., Trichostrongylus sp., Fasciola sp., and Moniezia sp. Amphistomes were encountered in swamp deer and livestock from both the sites. The parasitic species richness and prevalence however, varied between JJCR and KWLS.  The study recorded significant differences between the parasitic load in Swamp Deer with the eggs per gram of 487.5±46.30 at JJCR and 363.64±49.97 at KWLS at varying levels of livestock interactions.

Structural Integrity System Based on an Object-Oriented Activity- and Product Model

1993 ◽  
Author(s):  
Morten Lovstad ◽  
Tor G. Syvertsen
Keyword(s):  
Computational Models ◽  
Structural Integrity ◽  
Oil And Gas ◽  
Physical Structure ◽  
Gas Production ◽  
Structural Safety ◽  
Actual State ◽  
Product Model ◽  
The North ◽  
Analysis Models

Abstract Huge steel or reinforced concrete structures in deep waters support the installations for oil and gas production in the North Sea. Steady operations in a hostile environment require that structural safety and integrity is maintained. For rapid evaluation and assessment of structural integrity in case of modifications or urgency situations, Structural Integrity Systems are established, comprising computational models and structural analysis programs. A major problem for structural assessment at short notice is to keep the analysis models updated and consistent with the actual state of the physical structure and the loadings. This paper proposes a layered approach for model integration, which enable maintenance of the models at a high level, from which detailed analysis models are derived in a consistent manner.

scholarly journals The rise and fall of dialects in northern elephant seals

2018 ◽  
Vol 285 (1892) ◽  
pp. 20182176 ◽  
Author(s):  
Caroline Casey ◽  
Colleen Reichmuth ◽  
Daniel P. Costa ◽  
Burney Le Boeuf
Keyword(s):  
Mammalian Species ◽  
Structural Complexity ◽  
Mirounga Angustirostris ◽  
Geographical Differences ◽  
Migration Patterns ◽  
Elephant Seals ◽  
The North ◽  
Vocal Behaviour ◽  
Northern Elephant Seals ◽  
The North Pacific

Vocal dialects are fundamental to our understanding of the transmission of social behaviours between individuals and populations, however few accounts trace this phenomenon among mammals over time. Northern elephant seals ( Mirounga angustirostris ) provide a rare opportunity to examine the trajectory of dialects in a long-lived mammalian species. Dialects were first documented in the temporal patterns of the stereotyped vocal displays produced by breeding males at four sites in the North Pacific in 1968 and 1969, as the population recovered from extreme exploitation. We evaluated the longevity of these geographical differences by comparing these early recordings to calls recently recorded at these same locations. While the presence of vocal dialects in the original recordings was re-confirmed, geographical differences in vocal behaviour were not found at these breeding rookeries nearly 50 years later. Moreover, the calls of contemporary males displayed more structural complexity after approximately four generations, with substantial between-individual variation and call features not present in the historical data. In the absence of measurable genetic variation in this species—owing to an extreme population bottleneck—a combination of migration patterns and cultural mutation are proposed as factors influencing the fall of dialects and the dramatic increase in call diversity.

Structural Complexity and Distance from Source Habitat Determine Invertebrate Abundance and Diversity

Biotropica ◽  
2011 ◽  
Vol 43 (6) ◽  
pp. 738-745 ◽  
Author(s):  
Roger P. Mormul ◽  
Sidinei M. Thomaz ◽  
Alice M. Takeda ◽  
Rômulo D. Behrend
Keyword(s):  
Structural Complexity ◽  
Invertebrate Abundance ◽  
Abundance And Diversity

scholarly journals Late Holocene Sediment Deposition in Lake Wairarapa

2021 ◽  
Author(s):  
◽  
Martha Ingrid Trodahl
Keyword(s):  
New Zealand ◽  
Morphological Changes ◽  
Regional Scale ◽  
Hydrological Regime ◽  
Lake Management ◽  
Anthropogenic Influence ◽  
Eastern Shore ◽  
Ecological Value ◽  
The North ◽  
Development Scheme

<p>Lake Wairarapa is a highly modified lacustrine system at the southern end of the North Island, New Zealand. Not only is it situated in a region that is affected by catchment altering natural phenomena such as earthquakes, storms and fire, but both the catchment and hydrology of the lake have also been significantly altered by humans. Polynesian settlers arrived in the area approximately 700BP and proceeded to deforest the lowlands. European settlers began arriving from 1844AD onwards, completing deforestation of the lowlands and Eastern Uplands. In 1964 the Lower Wairarapa Valley Development Scheme was commissioned in an effort to alleviate flooding. This scheme significantly altered the hydrological regime of the lake. Interest in the condition of the lake and associated wetlands, and the realization that it has important recreational, cultural and ecological value, began to develop in the 1990's. This has led to a desire to see the lake restored to a more natural condition while still maintaining its flood protection capabilities. However, the lake has only been monitored over the last several decades. Any evidence of the lakes condition prior to this time is anecdotal and little is known of its natural tendencies and functions. This research has investigated and quantified morphological changes to Lake Wairarapa at the decadal and millenial scale using a combination of aerial photograph analysis, bathymetric survey comparison and lakebed core analysis. Study at these diverse scales has allowed the observed changes to be related to human environmental modification, while also being juxtaposed against natural trajectories of change. It is hoped that this can inform lake management and restoration efforts and provide a benchmark for measuring future changes to the lake, while also addressing wider issues concerning natural versus anthropogenic landscape change at the local and regional scale. The results of this project suggest that the lake has been steadily infilling over the last 6000BP – particularly along the eastern shore. For the two decades after significant hydrological changes to the lake associated with the Lower Wairarapa Valley Development Scheme, the rate of infilling on the eastern shore increased more than tenfold. However, this was accompanied by deepening in other parts of the lake. Today infilling along the eastern shore appears to have returned to natural rates and overall the lake in 2010 is only slightly smaller in volume than in 1975. Longer term anthropogenic influence on the lake and catchment was also evident. In particular Polynesian settlement and subsequent deforestation by fire was apparent in the lakebed cores. This result not only addresses the immediate issue of anthropogenic influence on this particular lacustrine system, but also informs the debate surrounding the dating of Polynesian arrival in New Zealand.</p>

scholarly journals Local changes in communities of wild bees (Hymenoptera: Apoidea, Apiformes): 30 years later

2014 ◽  
Vol 83 (4) ◽  
pp. 325-351 ◽  
Author(s):  
Józef Banaszak ◽  
Halina Ratyńska
Keyword(s):  
Agricultural Landscape ◽  
Plant Succession ◽  
Permanent Plots ◽  
Wild Bees ◽  
Natural Habitats ◽  
Increasing Trend ◽  
Quantitative Changes ◽  
Abundance And Diversity ◽  
Bee Communities ◽  
Forest Habitats

ABSTRACT Changes in communities of wild bees (Apiformes) were studied in relation to changes in vegetation in six permanent plots (natural forest habitats in the Wielkopolska National Park, and semi-natural habitats in the agricultural landscape near Turew) at the end of four decades (starting from the late 1970s). In 2008-2010, as many as 100 species of Apiformes were recorded there, which is more than reported in earlier decades. The most stable bee communities were those in forest habitats (oak-hornbeam forest, oak forest). Substantial qualitative and quantitative changes in vegetation and bee communities were recorded only after the renaturalisation of a former xerothermic grassland, which had become overgrown with shrubs and trees as a result of plant succession. Human interference (e.g. the felling of some trees growing along a road, clearance of understorey shrubs, ploughing of roadside margins) at selected refuge habitats in the agricultural landscape led to short-term fluctuations in bee abundance and diversity, but an increasing trend in abundance was noted.

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