Different Types Of Pressure Research Articles

Presiones de partes interesadas y eco-innovación en hoteles de México

The objective of this work is to analyse the impact of different types of pressure exerted by the interested parties in the implementation of eco-innovations. Using quantitative methodology, a structured questionnaire was applied to managers, owners or administrators of 70 hotels in Bahías de Huatulco and Cancun, Mexico. From a partial least squares structural equation model (PLS-SEM), the results show that the pressure of the market, competitors and clients influence eco-innovation. The contribution lies in relation to the role of stakeholder pressure in eco-innovation, particularly from the point of view of customers and competitors. In conclusion, eco-innovation arises as a hotel response to the requirements of the interested parties and facilitates obtaining competitive advantages and better performance. The recommendation is to strengthen a combination of command-and-control instruments with those of fiscal policy and subsidies according to the needs of the hotels

Fracture Resistance of Laboratory Composite Versus All-Ceramic Restorations in Class II Inlay Cavity Preparations: An In Vitro Study.

A posterior tooth's occlusal surfaces and the proximal surface can be restored by using an inlay, which is an intra-crown cast reconstruction without affecting the cusps of the tooth. When an inlay is prepared using an indirect approach, issues with traditional filling approaches, including poor morphology of the occlusal aspect or proximal aspect, inadequate resistance to wear, or subpar mechanical qualities of the directly inserted filler substance, are overcome. The current study was conducted in order to compare and assess the resistance to fracture of dental materials used in the preparation of inlay restorations indirectly, like composite restorations prepared by laboratories indirectly, inlays formed indirectly of monolithic translucent ceramic derived from zirconia, and inlays formed indirectly of traditional monolithic ceramic derived from zirconia. For the investigation, 100 human premolars of the maxilla that were extracted recently were chosen. A self-polymerizing acrylic resin was used to incorporate the tooth roots in a band made up of polyvinyl chloride up to 2 mm below the cement-enamel junction. The dimension of the band was 1.3 cm by 1.9 cm. Five categories of 20 specimens of such teeth were formed. Category one, featuring teeth in good condition, acted as the positive control category. The remaining four categories of teeth received inlay tooth preparation. The research samples underwent thermocycling after having been preserved for a full week following the cementation of inlay replacements. Then, in a universal testing apparatus, every sample endured axial compressive force with a metal globe delivered vertically at a crosshead rate of 1 mm/minute. The amount of force necessary to cause a fracture was measured in Newtons (N). The mean values of resistance against fracture in specimens in categories 1-5 were 1208.87 N, 614.89 N, 733.05 N, 1179.14 N, and 1148.49 N, respectively. The values of fracture resistance in specimens where an inlay cavity preparation was done but not filled were lower than those in traditional monolithic ceramic derived from zirconia and tooth specimens with inlays formed of monolithic translucent ceramic derived from zirconia, and the difference was significant statistically (p=0.001). The values of fracture resistance in composite inlay restorations prepared by laboratories were indirectly lower than those of monolithic ceramic derived from zirconia and tooth specimens with inlays formed of monolithic translucent ceramic derived from zirconia, and the difference was significant statistically (p=0.004). Within the constraints of the current investigation, we can state that indirect zirconia-based ceramic products offer adequate fracture resistance, but additional research is needed to determine how well these materials hold up under different types of pressures before employing them in clinical tooth restoration.

Behind the curtains of academic publishing: strategic responses of economists and business scholars

Bibliometric measurements are becoming omnipresent and crucially important for academic career decisions. The measured criteria induce strong incentives to align academics’ time and efforts. Based on a survey of economics and business scholars in German-speaking countries, this article empirically explores the interactions between scientific journal metrics and the behavior of authors in the publishing process. The impact different types of pressure have on their decisions is emphasized. In line with rational choice, authors generally move down in journal ranking as they resubmit their papers. While the process is highly influenced by random elements, the Scimago journal rank provides the best fit to researcher’s behavior. Doctoral students initially submit to lower ranked journals compared to higher academic positions, which is likely due to the time pressure they face. The empirical findings improve our understanding of strategic responses in the scientific publishing process. Qualified lotteries, along with other propositions, are suggested to mitigate adverse responses by academics.

Three thousand years of anthropogenic impact and water management and its impact on the hydro-ecosystem of the Mérantaise river, Paris conurbation (France)

This article assesses the long-term hydro-sedimentary and ecological consequences of the urban pressure around Paris over the last 3000 years on the Mérantaise river. Using a geoarchaeological approach combining sedimentological, geochemical, palynological and geophysical investigations enabled us to identify the transformations of the hydrosystem and to discuss the consequences of the different types of pressure and to put the role of biophysical and historical legacies into perspective with respect to contemporary dynamics. Using two study sites, one a former pond (Mérancis), the other a former mill site (Ors mill), nine cores, two auger holes and four trenches dug in the valley floor and two electrical resistivity tomography (ERT) profiles, it was possible to reconstruct the geometry of the sedimentary deposits. Chronostratigraphy was based on 41 radiocarbon dates and the history of vegetation and anthropogenic activities was reconstructed from 42 pollen samples and non-pollen palynomorphs collected from the former pond site. Despite the expansion of wetlands in the valley bottom, the pollen data revealed strong agropastoral activities and cereal growing in the Iron Age and up until the end of the Middle Ages. For the first time, sedimentological data associated with pollen data revealed hemp retting activities from c. 675 CE. From the Late Middle Ages onwards, water management led to the creation of two ponds to feed water mills. Despite the persistence of wetlands, this study highlights the early onset of anthropogenic modifications and in particular, the start of organic pollution and eutrophication in the Early Middle Ages, attesting to early eutrophication of water quality and aquatic environments resulting from the transformation of agropastoral practices and hydraulic pressure around the largest European city during the last 1500 years, well before the inset of urban sprawl in the watershed.

Functional trait responses to different anthropogenic pressures

There is an increasing awareness that knowledge of the functional diversity of a community is key to understand how the community responds to environmental and anthropogenic pressures. The Belgian Part of the North Sea (BPNS) represents a highly dynamic area that is subject to a variety of human activities. The main objective of this study is to investigate the usefulness of functional diversity indices and fuzzy correspondence analysis (FCA) to evaluate their applicability in assessing changes in benthic functional properties in the frame of environmental impact assessments (EIAs) for dredge disposal, sand extraction and offshore wind energy exploitation. Ten traits were selected, subdivided in 47 modalities, including both response- and effect traits. Functional diversity was quantified through different functional indices while shifts in trait composition due to anthropogenic pressure were determined by FCA. The analyses were based on a benthic dataset of 1262 samples.Results revealed that under chronic pressure of high disposal or sand extraction, the functional diversity indices – especially functional richness - showed a clear response. However, considerable variation (decrease/increase) was found for the index values between the impacted sites. Within the offshore wind farms, findings for the functional diversity indices were less pronounced. The FCA graphs revealed a shift in trait composition in all cases except for Macoma balthica and Nephtys cirrosa habitat in the dredge disposal case.The BPNS - with different types of pressure and levels of impact - provided the ideal platform to assess the potential of biological trait-based indicators. While responses are complex and dependent on several aspects such as local habitat, pressure type or level of impact, our results proved that functional trait analyses are a necessary and complementary tool in future environmental impact assessments.

The Thermographic Analysis of the Agglomeration Process in the Roller Press of Pillow-Shaped Briquettes.

When the briquetting process of fine-grained material takes place in the roller press unit, the pressure reached is over a hundred megapascals. This parameter is a result, among other factors, of the geometry of a compaction unit and also the properties of the consolidated material. The pressure of the unit is not constant and the changes in value depend on a given place on the molding surface. By the process of generating different types of pressure on the surface of briquettes, their compaction is different as well. The distribution of temperature on the surface of the briquettes may determine the pressure used locally on them. Nevertheless, the distribution of stress in the briquetting material is still a subject of scientific study. However, it is known that the pressure exerted on the briquette is different for different compaction systems. The article includes authors’ further thermography studies on the classical pillow-shaped briquetting process (instead of the saddle-shaped ones that were previously conducted) of four materials (calcium hydroxide and water mixture, mill scale, charcoal fines and starch mixture, as well as a mixture of EAFD, scale, fine coke breeze, molasses, and calcium hydroxide). Immediately after the briquettes left the compaction zone, thermal images were taken of them, as well as forming rollers. Thermograms that were obtained and the variability of temperature at characteristic points of the surface of pillow-shaped briquettes were analyzed. They showed differences in temperature on the surface of briquettes. In all four cases, the highest briquette temperatures were recorded in their upper part, which proves their better densification in this part. The temperature differences between the lower and upper part of the briquettes ranged from 1.8 to 9.7 °C, depending on the mixture.

Motivations to study: narratives of university graduates in rural Poland

ABSTRACT The article analyses motivations to obtain a higher education, as expressed by young university graduates living in rural areas in Poland, and factors underlying their decisions. Conceptually, the article draws from existing literature on rural youth’s educational aspirations and pathways. Findings are based on 92 in-depth interviews conducted with young adults with a university degree living in selected rural municipalities across Poland. The interviewees present a utilitarian approach towards university studies as a vehicle leading to higher social status and better local jobs. Their decisions are influenced mostly by family environment in comparison with school or community. The main contributions of this research concern insight into different types of pressures and encouragement present in the interviewees’ families, depending on whether or not their parents possess a university degree. Findings also indicate the importance of extended family networks as a source of support for first-generation rural students’ educational ambitions.

MECHANICAL PROPERTIES OF COWPEA BEANS AT DIFFERENT MOISTURE CONTENTS

Cowpea production has gained considerable ground in Brazil. Cowpea grain undergo different types of pressure and may crack and break during processing and storage, thus, there is a need to classify the mechanical properties of the beans. Therefore, this study aimed to evaluate the influence of the moisture content of cowpea beans on the maximum compressive force for fixed deformation and determine the proportional modulus of deformity under compression. The cowpea cultivars Novaera and Tumucumaque were evaluated at different moisture contents (0.12; 0.15; 0.18; 0.20; and 0.23 decimal d.b.). The experiment was arranged in completely randomized design for each moisture content and 10 deformation rates were applied (0.02; 0.04; 0.06; 0.08; 0.10; 0.12; 0.14; 0.16; 0.18; and 0.20 mm). The compression force was assessed using a universal testing machine and the proportional deformation modulus was determined. Following, hardness and elasticity of cowpea beans ??as a function of the moisture content were established. The compressive force required to deform cowpea beans decreases with increasing moisture content: between 2 and 105 N (Tumucumaque) and between 2 to 97 N (Novaera). The proportional deformation modulus of cowpea increased as the moisture content and deformation reduced, ranging from 4.9 x 107 to 31.9 x 107 Pa (Tumucumaque) and from 5.9 x 107 to 42 x 107 Pa (Novaera).

The Pressure Profiles of the Equilibrium States of Osmosis across Plant and Animal Cell Membranes

Introduction In our previous abstract titled “The Nature and Measures of Osmotic Pressure” in EB2021, we illustrated that 1) in a simple osmosis system where a solution compartment and a water compartment are separated by a selectively permeable membrane (m), πachieved, πapplied, and πTM (TM refers to transmembrane) are the three common ways osmotic pressure (π) is defined, where πTM is the nature of osmotic pressure that drives osmosis; and 2) in a composite osmosis system where a cell membrane separates two solutions (extracellular and intracellular fluids, i.e., ECF and ICF), the driving pressure of osmosis is the osmotic pressure difference/gradient (ΔπTM) across the m. In this presentation, we apply the concepts of a composite ECF-m-ICF and the ΔπTM to illustrate how three different types of pressure characterize the equilibrium states of osmosis (after water enters the cells) across plant and animal cell membranes. Method 1) Deconstructing a composite ECF-m-ICF (Fig 1) into two simple osmosis systems (ECF-m-H2O and H2O-m-ICF) to understand the ΔπTM. 2) Graphical (logical) analysis of the three pressures in plant and animal ECF-m-ICF (Fig 2). Results 1) As shown in Fig 1, ΔπTM = πTM(ECF-m-H2O) - πTM(H2O-m-ICF). 2) After water enters a cell and reaches equilibrium of osmosis, ΔπTM is reduced to Δπeq (Fig 2). 3) In a plant ECF-m-ICF (Fig 2a and 2b), large Δπeq (close to ΔπTM), high hydrostatic pressure (ΔPH2O, thick grey arrows in Fig 2b) inside the cell, and high tension in the call wall (ΔTwall, thick white bidirectional arrows, Fig 2b) characterize this equilibrium state. To focus on the pressure profiles and simplify the Fig 2, the vacuoles that store water in the plant cell are not shown. In contrast, in an animal ECF-m-ICF, smaller Δπeq, lower PH2O (the thin grey arrows, Fig 2d), and lesser tension in the cell membrane (ΔTCM, the white bidirectional arrows, Fig 2d) characterize the equilibrium state. Conclusion This is the first work to illustrate in detail the differences in the three pressure profiles across plant and animal cell membranes after water enters the cells due to osmosis using the method of deconstruction of ICF-m-ECF and the concept of ΔπTM.

Inter-Organizational Paradox Management: How national business systems affect responses to paradox along a global value chain

This study discusses the relationship between inter-organizational paradox management, national business systems and global value chains. Using case study evidence from a global value chain in the footwear industry (in Germany and China), we analyse how different businesses in the chain responded to the paradoxical tension arising from the competing demands to provide a living wage to workers and to uphold financial performance. Our findings highlight organizational responses to this paradox along the value chain, showing how these responses were shaped by the interplay of different types of pressures exerted by national business systems and the value chain itself. While these pressures were aligned in the German part of the chain, they were not aligned on the Chinese side. The study makes two contributions: (1) we develop a taxonomy outlining how the alignment of different types of pressures influences whether organizations choose either proactive or defensive paradox management; and (2) we argue that theorizing the impacts of cross-national distance on paradox management can be enhanced by adopting a multidimensional approach to institutional variety that extends beyond culture-based arguments.

Effects of anthropogenic pressures on diatom communities using morphological and molecular approaches

The relevance of molecular composition of diatom assemblages to detect river impairment caused by different intensive land uses (industrial, agricultural, and urbanization) was tested in this study with data from two rivers (Ferreira and Sousa rivers) and 21 sampling sites located in the north of Portugal. The Water Framework Directive (WFD) gives the legal basis for the use of this ecological indicator for water quality assessment (Vasselon et al. 2017 ). However, the morphological identification and count of diatoms using the light microscope requires a high level of expertise, is time-consuming and costly (Valentin et al. 2019). DNA metabarcoding combined with high-throughput sequencing techniques (HTS), offers a promising alternative to classic methodologies, reducing time and costs (Mortágua et al. 2019 ). Thus, here we compared the response of the two approaches in terms of ecological assessments (IPS Ecological Quality Ratios) to the different types of pressures felt in the 21 sites. Diatoms were sampled at 21 sites located in the North of Portugal in autumn of 2019 (Fig. 1). Samples were submitted in parallel to the molecular and morphological analyses. The eDNA was extracted, PCR amplified (312 bp rbcL DNA barcode), and finally sequenced (Illumina MiSeq). The Mothur software was used to obtain the Operational Taxonomic Units (OTUs), which were then taxonomically assigned to the species through the R-Syst::diatom version 7.1 (Rimet et al. 2018) reference library. EQR values indicated a good correlation between morphological and molecular methods (Fig. 2). PCA analysis (Fig. 3 ) revealed that in urban, agricultural, and industrial areas there is a greater concentration of nutrients (phosphorus and nitrogen), organic matter, and heavy metals due to the discharge of urban/industrial effluents, while in places considered natural (without any type of anthropogenic pressure) we find low levels of these pollutants and high concentrations of dissolved oxygen (DO). The BEST (BIO-ENV) analysis (Tables 1, 2) shows in the case of the morphological approach, the combination of 4 environmental variables (NO₃⁻, Li, K, and Cu) is highly correlated with the biological patterns, and in the molecular approach the combination of only 2 of the environmental variables (Li and K), explains the distribution of diatom communities composition and has a slightly higher correlation. The morphological methodology seems to demonstrate a better response to urban pressures, mainly to effluent discharges, while the molecular one demonstrates a more diffuse response with special emphasis on good correlation with variables such as zinc and nitrate, which may also be related to effluent discharges and use of fertilizers in agriculture. However, it is necessary to improve the reference library so that there is a better response of the molecular methodology to the existing pressures.

A microbial mandala for environmental monitoring: Predicting multiple impacts on estuarine prokaryote communities of the Bay of Biscay.

Routine monitoring of benthic biodiversity is critical for managing and understanding the anthropogenic impacts on marine, transitional and freshwater ecosystems. However, traditional reliance on morphological identification generally makes it cost-prohibitive to increase the scale of monitoring programmes. Metabarcoding of environmental DNA has clear potential to overcome many of the problems associated with traditional monitoring, with prokaryotes and other microorganisms showing particular promise as bioindicators. However, due to the limited knowledge regarding the ecological roles and responses of environmental microorganisms to different types of pressure, the use of de novo approaches is necessary. Here, we use two such approaches for the prediction of multiple impacts present in estuaries and coastal areas of the Bay of Biscay based on microbial communities. The first (Random Forests) is a machine learning method while the second (Threshold Indicator Taxa Analysis and quantile regression splines) is based on de novo identification of bioindicators. Our results show that both methods overlap considerably in the indicator taxa identified, but less for sequence variants. Both methods also perform well in spite of the complexity of the studied ecosystem, providing predictive models with strong correlation to reference values and fair to good agreement with ecological status groups. The ability to predict several specific types of pressure is especially appealing. The cross-validated models and biotic indices developed can be directly applied to predict the environmental status of estuaries in the same geographical region, although more work is needed to evaluate and improve them for use in new regions or habitats.

Reliability of the Pressure Indicating Film for Occlusal Force Analysis: A Pilot Study

Objective: The aim of this study was to evaluate the reliability of the pressure indicating film in measuring pressure exerted on it with and without Polyethylene (PE) sleeve as infection control purposes, and to analyze the pressure produced with its software for occlusal force study. Materials and Methods: The optimization of the pressure indicating film for occlusal force analysis commenced with the design and calibration of this sheet. The film was designed into horseshoe shape to suit the shape of maxillary and mandibular arches. The calibration was initiated with 5 different types of pressure which were 15 MPa, 25 MPa, 30 MPa, 35 MPa and 45 MPa exerted on two groups of the film: (i) with PE sleeve and (ii) without PE sleeve. Three readings were recorded for each group and mean value was documented. Then, the films were calibrated by its software for pressure analysis. Results: There was no significance difference found between the film with and without PE sleeve during the calibration stage (P>0.05). In all groups of pressure, there was no significant difference documented between pressure exerted and read out value. Conclusion: The results suggested that the film can be used for occlusal force analysis and improvement of the film with addition of PE sleeve for hygienic purpose is suitable to form the basis of clinical occlusal forces study.

Bioindicators or sediment relationships: Evaluating ecological responses from sandy beach nematodes

Sandy beaches from tropical countries are currently facing many challenges due to rapid urban development and its impacts on coastal areas. Despite their aesthetic, recreational and ecological importance, these environments are neglected when it comes to assessment and conservation measures, which can be done in several ways, including biomonitoring. Nematodes are amongst the most suitable organisms to be used as ecological indicators in sandy beaches due to their high abundance on marine sediments and its rapid responses to different sorts of impacts. We analyzed the nematode assemblages and the environmental variables from seven sandy beaches under different types of pressure from Rio de Janeiro state, in Brazil, and applied the biological indexes that use nematodes as bioindicators in order to evaluate differences on the ecological status of these beaches. Sampling took place in the summer of 2015, during the spring low tide. Physicochemical characteristics, microbiology and granulometry were measured alongside human density on each of the beaches and linked to nematode distribution found on the intertidal zone. Botafogo beach, already known for being highly affected by sewage disposal, showed high values for organic matter content and the least diverse assemblage, with high dominance from genus Chromadorita. Despite the higher human density, most urban and touristic beaches (Barra da Tijuca and Copacabana) did not show distinct values for the diversity measures when compared to the most preserved beaches (Restinga da Marambaia and Fora - Urca). While the applied biological indexes did not show clear answers concerning the ecological health of the studied sites; the sediment sorting coefficient was the variable that best explained the nematode distribution and some genera are associated to certain spectrums with this variable. For instance, opportunist genera such as Daptonema and Theristus were found on broader spectrums of sorting coefficient while predators with bigger body diameters showed a more restricted distribution. As the mean grain size is still considered the main variable on nematode distribution for sandy beaches, this study reveals that the sorting coefficient also gives important answers for the nematode distribution.

Spatial distribution of Donax trunculus (Linnaeus, 1758) populations along the intertidal area of the Gulf of Cádiz (SW, Spain)

Spatial distribution of Donax trunculus (Linnaeus, 1758) populations along the intertidal area of the Gulf of Cádiz (SW, Spain)

Pressure and impact of anthropogenic litter on marine and estuarine reptiles: an updated “blacklist” highlighting gaps of evidence

We report an arrangement on the effect of anthropogenic litter on marine and estuarine reptiles, checking for evidence about different types of impact (ingestion vs. entanglement) and pressure (three size-based categories). From 1976 to 2018, we obtained a "blacklist" of 11 species impacted by marine litter (about 13% of 85 species of marine and estuarine reptiles), belonging to three orders (Testudines, Squamata, and Crocodilia). We obtained only occasional evidence of an impact for Squamata (Hidrophis elegans, Disteira major) and Crocodilia (Crocodylus porosus). Regarding the different types of pressure, the highest number of evidence has been obtained for macro-litter (10 species) and the lowest for micro-litter (4 species, all Chelonidae). Among Testudines, Lepidochelys kempii and Natator depressus evidenced a lack of data for micro-plastic. In Squamata, information is lacking for micro-plastic with only occasional references for meso-plastic (in Hydrophis elegans) and macro-plastic (Disteira major and Crocodylus porosus). We obtained a direct correlation between the research effort and the number of citations regarding different types of pressure and impact of marine litter: therefore, our blacklist of impacted species could be increased, carrying out further research focused on other poorly studied marine and estuarine reptiles. We suggest the use of a standardized nomenclature to reduce the amount of lost information.

Metals and limnological variables in an urban reservoir: compartmentalization and identification of potential impacted areas.

Reservoirs in urban areas are used for different purposes and are liable to different types of pressures that can cause the loss of chemical and biological quality, hence diminishing their ecological, economic, and cultural benefits. Here, a study of surface water heterogeneity was undertaken at the Guarapiranga urban reservoir (São Paulo, Brazil) in order to improve understanding of the structure and functioning of these ecosystems. Sampling was performed during the dry and rainy seasons at 33 sites. Limnological variables and total contents of the metals cadmium, nickel, lead, and zinc were analyzed. The risks associated with the metals were evaluated based on the toxicity unit approach. A principal component analysis enabled differentiation of the reservoir into six different areas. Some of the most powerful discriminatory variables (nutrients and metals) showed the existence of anthropogenic impacts on the system. The most strongly affected compartments were located in the following: (1) upstream area, under the influence of the Parelheiros stream, with the highest total phosphorus levels (318mgL-1) and (2) dam area, with high values for total nitrogen, suspended organic matter, total solids, and pH. The results for the dam compartment were a consequence of substantial urbanization and a longer residence time. Despite high levels of cadmium during the rainy season, no significant potential risk for zooplankton was observed. The data indicated the need to control unauthorized land occupation and to implement adequate sanitation in the Guarapiranga watershed. This research provides information that should assist water resource agencies in the sustainable management of urban reservoirs.

The impact of emotional intelligence on auditor judgment

This study seeks to identify emotional intelligence (EI) as a key factor in dealing with emotions and pressures in an audit context. In this paper, we focus on how EI may influence the relation between job pressures (i.e., time budget pressure and client pressure) and auditors' judgment. Specifically, we investigate the moderating effect of EI on auditors' third‐person assessments of an auditor's actions when subject to internal and external pressures. The results suggest that the moderating influence of EI can effectively reduce auditors' tendency to engage in dysfunctional behavior and improve audit quality. Further, moderation analysis suggests that EI is a significant mechanism that moderates the effects of different types of pressure on auditors' judgments.

Links between epibenthic community patterns and habitat characteristics in the Parila lagoon (Croatia)

The aim of the study was to describe epibenthic macroinvertebrates and demersal fish and to identify links between spatial patterns and habitat characteristics (sediment, salinity, oxygen and temperature). The research was performed in the Parila lagoon in Croatia ; an important nursery ground where conditions in epibenthic community can have significant direct and indirect impact on fisheries. Diversity (30 species) and abundance (from 0 to 7 ind m−2) of epibenthic assemblages was low on all stations and showed remarkable seasonal changes. Such patchiness could support the estuarine quality paradox idea, i.e. the most abundant species are well adapted to changing conditions in a variable environment. The ecological analysis showed that total phosphorus concentration (TP), temperature (T) and salinity (S) were the main environmental parameters affecting community structure of the Parila lagoon. Six species listed as frequent (Nerophis ophidion, Zosterisessor ophiocephalus, Syngnathus typhle, Cerastoderma glaucum, Palaemon adspersus and Carcinus aestuarii) have a potential to be used as indicators of habitat quality. In terms of trophic diversity, community was dominated by carnivores and omnivores. Fish trophic index (above 2.7) indicated upward shift of the local food chain and towards mostly carnivorous species, while the absence of herbivorous species pointed to low environmental quality. The present study gives an insight into the current ecological conditions in the Parila lagoon. Further research about the sensitivity of these potential indicators to different types of pressure is necessary in order to select robust early-warning indicators framework.

Evaluation of Drip Irrigation Emitters Distributing Primary and Secondary Wastewater Effluents

Drip irrigation is a reliable and efficient way to deliver water to the soil; however, drip emitter clogging is a major concern when irrigating treated wastewater. Four types of drip irrigation emitters from three manufacturers were analyzed over a one-year period to monitor the incidence of clogging and its effect on irrigation uniformity. A controlled laboratory experiment was conducted using two different types of pressure compensating emitters designed for reclaimed wastewater, one type of non-pressure compensating emitter designed for reclaimed wastewater, and one type of non-pressure compensating agricultural emitter designed for potable water applications. Emitters of each type distributed tap water, primary treated septic tank effluent, and secondary treated sand filter effluent. Emitter flow rates were measured each month to identify clogged or flow restricted emitters. Some clogging was seen in each type of emitter over the course of the experiment and emitter flow rates fluctuated over time, suggesting that clogging was gradual and often incomplete. Many of the emitters exhibited a cyclical flow rate indicating that clogging was reversible. The emitters distributing septic tank effluent exhibited the most significant reduction in flow. The most severely clogged emitter experienced a reduction of 63% after one year of irrigation with septic tank effluent. Secondary treatment using the sand filter showed the least clogging in all four types of emitters. One of the reclaimed wastewater emitter types experienced an average reduction in flow of 1% while the other two actually increased in flow by1% and 4% after one year of irrigation with effluent from a sand filter. Water quality appeared to have a more pronounced effect than did emitter type. The effect of wastewater type on emitter discharge was +3.3% for tap water, -9.4% for septic tank effluent and -0.3% for effluent from secondary sand filtration. While the agricultural drip emitters experienced a significant negative impact after one year of operation the three drip emitters designed for distributing septic tank effluent and reclaimed wastewater showed little clogging and a high degree of uniformity.