scholarly journals Niche Partitioning at Emergence of Two Syntopic Dragonflies

Ecologies ◽  
2021 ◽  
Vol 2 (1) ◽  
pp. 16-26
Author(s):  
Elena Piano ◽  
Stefano Mammola ◽  
Martina Dalle ◽  
Elisa Riservato ◽  
Marco Isaia
Keyword(s):  
Key Management ◽  
Aquatic Vegetation ◽  
Management Practice ◽  
Niche Partitioning ◽  
Environmental Parameters ◽  
Niche Space ◽  
Ecological Requirements ◽  
Nw Italy ◽  
The One ◽  
Emergence Phase

We investigated the ecological requirements in the emergence phase of two congeneric species of Aeshnidae, Aeshna grandis (Linnaeus 1758) and A. juncea (Linnaeus 1758), occurring in syntopy at the southernmost limit of their range. We sampled the exuviae of the two species at the peak of their emergence in three lakes in NW Italy. In each lake we defined 30 to 50 sampling plots along the lake borders where we checked for the presence of exuviae and collected data on the microhabitat composition. By modeling the response of the exuviae presence and abundance against the environmental parameters, we could highlight a partial differentiation in the ecological requirements of the two species at emergence. In particular, A. grandis is more influenced by the structure of the aquatic vegetation than A. juncea and the niche space occupied by A. grandis is wider, almost totally encompassing the one of A. juncea. We argue that A. grandis exploits microhabitats rich in aquatic plants to avoid competition with A. juncea. We suggest the preservation of well-structured aquatic vegetation as a key management practice to preserve the three studied populations of A. grandis, a species which has been recognized as Vulnerable for Italy according to the IUCN criteria.

Sources of Nitrogen and Phosphorus in the Catchment Area of Neusiedlersee/Fertö, Austria/Hungary

1993 ◽  
Vol 28 (3-5) ◽  
pp. 101-110 ◽  
Author(s):  
W. v. d. Emde ◽  
H. Fleckseder ◽  
N. Matsché ◽  
F. Plahl-Wabnegg ◽  
G. Spatzierer ◽  
...  
Keyword(s):  
Point Source ◽  
Catchment Area ◽  
Management Practice ◽  
Water Erosion ◽  
Nonpoint Source ◽  
Point Sources ◽  
Source Control ◽  
Nitrogen And Phosphorus ◽  
Catchment Areas ◽  
The One

Neusiedlersee (in German) / Fertö tó (in Hungarian) is a shallow lake at the Austro-Hungarian border. In the late 1970s, the question arose what to do in order to protect the lake against eutrophication. A preliminary report established the need for point-source control as well as gave first estimates for non-point source inputs. The proposed point-source control was quickly implemented, non-point sources were - among other topics - studied in detail in the period 1982 - 1986. The preliminary work had shown, based on integrated sampling and data from literature, that the aeolic input outweighed the one via water erosion (work was for totP only). In contrast to this, the 1982 - 1986 study showed that (a) water erosion by far dominates over aeolic inputs and (b) the size of nonpoint-source inputs was assessed for the largest catchment area in pronounced detail, whereas additional estimates were undertaken for smaller additional catchment areas. The methods as well as the results are presented in the following. The paper concludes with some remarks on the present management practice of nonpoint-source inputs.

scholarly journals Investigation of an Electrostatic Discharge Protective Biodegradable Packaging Foam in the Logistic Chain

2014 ◽  
Vol 5 (1) ◽  
pp. 25-33 ◽  
Author(s):  
Ákos Mojzes ◽  
Barnabás Tóth ◽  
Péter Csavajda
Keyword(s):  
Electrostatic Discharge ◽  
Technological Development ◽  
Environmental Parameters ◽  
Thermoplastic Starch ◽  
Vital Role ◽  
Packaging Materials ◽  
Negative Effects ◽  
Packaging System ◽  
Product Packaging ◽  
The One

Abstract Since the beginning of the 20th century, logistics has undergone a huge technological development, which has, however, resulted in many negative effects as well. The industry, particularly in the packaging industry has been a massive waste producer, although recently it has forced the use of new materials and it started to focus on environmentally friendly technologies. During the transportation of finished and semi-finished Electrostatic Discharge (ESD) sensitive products, the product packaging system has a vital role. These kind of packaging materials must be suitable to both logistic (protection against mechanical and environmental stresses) and special ESD protection requirements. During the transportation of printed-circuit electronic products, ESD defense is then of primary significance. However there is a huge disadvantage for the use of various shield bags. Namely, this kind of associated packaging is particularly pollutant, it causes a lot of inconvenience in the form of waste. In order to rule out these materials from the packaging system, new innovative solutions have to be found. The investigated TPS (thermoplastic starch biodegradable foam) is subjected to a validation, a long process to certify that this material unites properties of two types of packaging materials at the same time. On the one hand, this packaging foam has to meet the requirements product defense. On the other hand, the material must be anti-static under the logistic stress effects. In case it is found suitable, it can be an alternative of the conventional materials. In this article, we investigate the ESD characteristic of TPS foam. As this material sensitive for environmental parameters during transportation, we make the relevant Surface Resistance (Rs) tests on different temperature and humidity conditions. Based on result, the decision of the application can be done, as an ESD packaging material.

scholarly journals Biståndshandläggare om möten med sent-i-livet-invandrade äldre – inblick i hur en institutionell kategori skapas

2016 ◽  
Vol 22 (1) ◽  
Author(s):  
Sandra Torres ◽  
Anna Olaison ◽  
Emilia Forssell
Keyword(s):  
Care Management ◽  
Management Practice ◽  
Elderly Care ◽  
Cross Cultural ◽  
Cultural Interaction ◽  
Assessment Practice ◽  
Care Services ◽  
Care Managers ◽  
Group Interviews ◽  
The One

Care managers on need assessment with late-in-life immigrants: insights into how an institutional category is created Research on the implications of cross-cultural interaction for needs assessment practice is scarce. This is particularly the case when it comes to research on care management within elderly care. There is therefore a need to explore the ways in which care managers regard and experience cross-cultural interaction when assessing older people’s needs prior to granting access to elderly care services. This article is based on a project that aimed to explore just that through focus group interviews with care managers (n=60) who work within the context of Swedish elderly care. The analysis presented here addresses the ways through which an institutional category is created as care managers discuss the kind of cross-cultural interaction that they find the most challenging (which is the one involving older people who migrated late, do not speak Swedish and come from cultures that are deemed to be too different). The analysis discloses the underlying assumptions about Otherness that the care managers alluded to when sharing their views on, and experiences of, assessing needs by way of cross-cultural interaction with late-in-life immigrants. The article discusses the implications that these findings have for care management practice in Sweden considering that the legislation dictates that care managers need to attend to older people’s “uniqueness”. The analysis reveals that the uniqueness associated with certain client categories is too unique to cater for

scholarly journals A phytosociological survey of aquatic vegetation in the main freshwater lakes of Greece

2020 ◽  
Vol 1 ◽  
pp. 53-75
Author(s):  
Dimitrios Zervas ◽  
Ioannis Tsiripidis ◽  
Erwin Bergmeier ◽  
Vasiliki Tsiaoussi
Keyword(s):  
Plant Communities ◽  
Aquatic Plant ◽  
Aquatic Vegetation ◽  
Environmental Parameters ◽  
Hierarchical Cluster ◽  
Freshwater Lake ◽  
Vegetation Types ◽  
Freshwater Lakes ◽  
Lake Ecosystems ◽  
The Relationship

Aims: This study aims to contribute to the knowledge of European freshwater lake ecosystems with updated and new information on aquatic plant communities, by conducting national-scale phytosociological research of freshwater lake vegetation in Greece. Moreover, it investigates the relationship between aquatic plant communities and lake environmental parameters, including eutrophication levels and hydro-morphological conditions. Study area: Lakes in Greece, SE Europe. Methods: 5,690 phytosociological relevés of aquatic vegetation were sampled in 18 freshwater lake ecosystems during 2013–2016. The relevés were subjected to hierarchical cluster and indicator species analyses in order to identify associations and communities of aquatic vegetation, as well as to describe their syntaxonomy. Multiple regression analysis was applied to investigate the relationship between vegetation syntaxa and environmental parameters of lakes, i.e. physico-chemical parameters and water level fluctuation. Results: Ninety-nine plant taxa belonging to 30 different families were recorded. Forty-six vegetation types were identified and described by their ecological characteristics, diagnostic taxa and syntaxonomical status. Thirteen vegetation types, the largest number belonging to the vegetation class Charetea, are considered to be new records for Greece. The distribution of the vegetation types recorded in the 18 freshwater lakes was found to depend on environmental parameters and levels of eutrophication. Conclusions: An updated aquatic vegetation inventory was produced for Greek lakes, and primary results showed that the presence/absence of aquatic plant communities and the community composition in freshwater lakes can be utilized to assess the pressure of eutrophication on lake ecosystems. Taxonomic reference: Euro+Med (2006–). Abbreviations: MNT = Mean number of taxa; WFD = Water Framework Directive.

scholarly journals Model Sistem Monitoring pH dan Kekeruhan pada Akuarium Air Tawar berbasis Internet of Things

METANA ◽  
2019 ◽  
Vol 15 (2) ◽  
pp. 49-56
Author(s):  
Dista Yoel Tadeus ◽  
Khasnan Azazi ◽  
Didik Ariwibowo
Keyword(s):  
Internet Of Things ◽  
Monitoring System ◽  
Aquatic Vegetation ◽  
Ph Value ◽  
Low Cost ◽  
Environmental Parameters ◽  
Ornamental Fish ◽  
Automation System ◽  
Water Turbidity ◽  
Air Filter

Ikan hias dan vegetasi air memiliki rentang toleransi terhadap nilai parameter lingkungan. Parameter tersebut hendaknya senantiasa diawasi demi kelangsungan hidupnya. Internet of Things (IoT) telah dimanfaatkan sebagai sistem monitoring dan otomasi parameter lingkungan ikan dan vegetasi air namun sistem ini membutuhkan biaya yang tinggi. Tujuan penelitian ini adalah mengembangkan suatu model sistem monitoring berbasis IoT berbiaya rendah untuk memberikan informasi parameter pH dan kekeruhan air setiap saat kepada pemilik ikan hias. Sistem ini dibangun menggunakan komponen opensource dan sensor berbiaya rendah. Data monitoring digunakan untuk mengaktifkan aktuator berupa filter air. Filter akan aktif apabila tingkat kekeruhan air sudah melebihi batas kekeruhan yang ditentukan. Pengujian kekeruhan air aquarium menunjukkan saat kekeruhan mencapai 3000 ntu pukul 14.12 pompa aktif dan filter bekerja sampai kekeruhan berada pada nilai 498 ntu pada pukul 17.00 dan pompa mati secara otomatis. Nilai pH dan kekeruhan air berhasil ditampilkan dengan baik di aplikasi Blynk pada ponsel. Hasil pengujian menyimpulkan bahwa sistem monitoring yang dikembangkan telah berhasil diimplementasikan dengan baik.  Ornamental fish and aquatic vegetation have a tolerance range of environmental parameter values. These parameters should always be monitored for survival. Internet of Things (IoT) has been utilized as a monitoring and automation system for environmental parameters of fish and aquatic vegetation, but this system requires high costs. The purpose of this study is to develop a low-cost IoT-based monitoring system model to provide information on pH parameters and water turbidity at any time to ornamental fish owners. This system is built using opensource components and low-cost sensors. Monitoring data is used to activate the actuator in the form of a water filter. The filter will active if the turbidity level of water has exceeded the specified turbidity limit. The aquarium water turbidity test showed that when the turbidity reached 3000 ntu at 14.12 the pump was active and the filter worked until the turbidity was at 498 ntu at 17.00 and the pump automatically shut down. The pH value and the turbidity of the water were successfully displayed in the Blynk application on the cellphone. The test results concluded that the monitoring system developed was successfully implemented. 

Evaluation of an indoor environmental quality model for very small residential units

2018 ◽  
Vol 28 (4) ◽  
pp. 470-478 ◽  
Author(s):  
Kwok Wai Mui ◽  
Tsz Wun Tsang ◽  
Ling Tim Wong ◽  
Yuen Ping William Yu
Keyword(s):  
Environmental Quality ◽  
Residential Buildings ◽  
Residential Building ◽  
Environmental Parameters ◽  
Small Variation ◽  
Indoor Environmental Quality ◽  
Quality Model ◽  
Small Unit ◽  
Residential Units ◽  
The One

This study investigates the indoor environmental quality (IEQ) responses from occupants living in very small residential units that are unique to Hong Kong. Through the changes in environmental parameters, including thermal, indoor air quality, visual and aural, the study demonstrates that the overall IEQ acceptance in these units is different from the one in general residential building environments. Results show that occupants of these units are more sensitive to warmth and operative temperature change as compared to occupants of general residential buildings. A small variation of thermal acceptance suggests that the small unit occupants have already developed certain degree of tolerance to hot conditions. The adaptation to the reality of a hot environment is also reflected in the overall IEQ acceptance. It is believed that very small space residents have developed tolerance and adaptation to an unchangeable reality, changing environmental conditions does not necessarily alter their acceptance of individual IEQ aspects and overall IEQ.

Sewage Sludge as Raw-Material in Asphalt Mixtures

2013 ◽  
Vol 664 ◽  
pp. 638-643 ◽  
Author(s):  
Maria del Pilar Durante Ingunza ◽  
Olavo Francisco dos Santos Júnior ◽  
Sayonara Andrade Medeiros
Keyword(s):  
Mechanical Performance ◽  
Environmental Parameters ◽  
Empty Space ◽  
Asphalt Mixtures ◽  
International Standards ◽  
Raw Material ◽  
Air Voids ◽  
The One ◽  
Consequent Increase ◽  
Space Volume

The aim of this study is to assess the volumetric and mechanical behavior of concrete asphalt mixtures, using natural sludge as a partial substitute for the tiny aggregate and calcined sludge as filler. This assessment was performed based on technical and environmental parameters, using laboratory tests obeying current Brazilian norms, according to international standards. The addition of natural sludge to the mixtures has increased stability, increased air voids contents of the mixtures. The addition has compromised mixture adhesiveness. With respect to the addition of calcined sludge to the mixtures, the mixtures with calcined sludge displayed the same behavior as those with cement. It was observed decrease in empty space volume of the mixtures and consequent increase in empty space-bitumen relation and increased stability. The mixture addition of natural sludge that has the best mechanical and volumetric performance is the one with 7.5% of natural sludge in the granulometric composition of the mixture. The mixture with 1% of calcined sludge had the best volumetric and mechanical performance.

scholarly journals Seasonal niche differentiation between evolutionary closely related marine bacteria

2020 ◽  
Author(s):  
Adrià Auladell ◽  
Albert Barberán ◽  
Ramiro Logares ◽  
Esther Garcés ◽  
Josep M. Gasol ◽  
...  
Keyword(s):  
Marine Bacteria ◽  
Niche Partitioning ◽  
Environmental Parameters ◽  
Niche Overlap ◽  
Niche Differentiation ◽  
Habitat Filtering ◽  
Coastal Marine ◽  
Class Level ◽  
Nucleotide Divergence ◽  
Selection Of

AbstractBacteria are highly dynamic in marine environments, where they play key biogeochemical roles. Here, we tested how similar the niche of closely related marine bacteria is and what are the environmental parameters modulating their ecological responses in a coastal oligotrophic time series. We further explored how conserved the niche is at broader taxonomic levels. We found that, for certain genera, niche similarity decreases as nucleotide divergence increases between closely related amplicon sequence variants, a pattern compatible with selection of similar taxa through habitat filtering. Additionally, we observed evidence of niche partitioning within various genera shown by the distinct seasonal patterns of closely related taxa. At broader levels, we did not observe coherent seasonal trends at the class level, with the order and family ranks conditioned to the patterns that exist at the genus level. This study explores the coexistence of niche overlap and niche partitioning in a coastal marine environment.

scholarly journals Growth and Habitat Use of Guadalupe Bass in the South Llano River, Texas

2019 ◽  
Vol 11 (1) ◽  
pp. 33-45
Author(s):  
Jillian R. Groeschel-Taylor ◽  
Seiji Miyazono ◽  
Timothy B. Grabowski ◽  
Gary P. Garrett
Keyword(s):  
Flow Regime ◽  
Habitat Restoration ◽  
Aquatic Vegetation ◽  
Multiple Scales ◽  
Spatial Scales ◽  
Low Cost ◽  
Habitat Associations ◽  
Life History Stage ◽  
The South ◽  
Ecological Requirements

Abstract Predicting how stream fishes may respond to habitat restoration efforts is difficult, in part because of an incomplete understanding of how basic biological parameters such as growth and ontogenetic habitat shifts interact with flow regime and riverscape ecology. We assessed age-specific Guadalupe Bass Micropterus treculii habitat associations at three different spatial scales in the South Llano River, a spring-fed stream on the Edwards Plateau of central Texas, and the influence of habitat and flow regime on growth. We classified substrates using a low-cost side-scan sonar system. We used scale microstructure to determine age and to back-calculate size at age. Over 65% of captured Guadalupe Bass were age 2 or age 3, but individuals ranged from 0 to 7 y of age. Habitat associations overlapped considerably among age classes 1–3+, but age-0 Guadalupe Bass tended to associate with greater proportions of pool and run mesohabitats with submerged aquatic vegetation. Although habitat metrics across multiple scales did not have a large effect on growth, river discharge was negatively correlated with growth rates. Understanding age-specific Guadalupe Bass habitat associations at multiple scales will increase the effectiveness of restoration efforts directed at the species by assisting in determining appropriate ecological requirements of each life-history stage and spatial scales for conservation actions.

scholarly journals Management, productivity and firm heterogeneity in international trade

2019 ◽  
Vol 28 (82) ◽  
pp. 1-18 ◽  
Author(s):  
Javier Serrano ◽  
Rafael Myro
Keyword(s):  
International Trade ◽  
Key Management ◽  
Design Methodology ◽  
Management Practices ◽  
Firm Heterogeneity ◽  
Management Practice ◽  
Content Type ◽  
Management Quality ◽  
Good Management Practice

Purpose This paper aims to analyse the relevance of management and productivity in the behaviour of firms in international trade. Design/methodology/approach Using a survey of Spanish manufacturing firms, the authors use a management quality index to serve as a proxy for the good management practice of the firm. Findings The results demonstrate that exporter and multinationals firms are more productive and better managed than domestic firms. Furthermore, in the periods in which switcher firms decide to export or to invest abroad, they are better managed but are not more productive than in the rest of the periods. Finally, results indicate that regardless of its positive relationship with productivity, management also has a direct impact on the firm’s probability of exporting and involving in foreign direct investment. Originality/value This paper aims to reconcile the recent international trade literature, which focusses on the role of productivity heterogeneity in international trade, with the international business literature, concentrated on depicting the key management practices that impact internationalization.

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