Search results for: Problematic soils

Authors: Sean T. S. Wei, Joy D. Van Nostrand, Annapoorna Maitrayee Ganeshram, Stephen B. Pointing

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McMurdo Dry Valleys are a largely ice-free polar desert protected by international treaty as an Antarctic special managed area. The terrestrial landscape is dominated by oligotrophic mineral soil with extensive rocky outcrops. Several environmental stresses: low temperature, lack of liquid water, UV exposure and oligotrophic substrates, restrict the major biotic component to microorganisms. The bacterial diversity and the putative physiological capacity of microbial communities of quartz rocks (hypoliths) and soil of a maritime-influenced Dry Valleys were interrogated by two metagenomic approaches: 454 pyro-sequencing and Geochp DNA microarray. The most abundant phylum in hypoliths was Cyanobacteria (46%), whereas in solils Actinobacteria (31%) were most abundant. The Proteobacteria and Bacteriodetes were the only other phyla to comprise >10% of both communities. Carbon fixation was indicated by photoautotrophic and chemoautotrophic pathways for both hypolith and soil communities. The fungi accounted for polymer carbon transformations, particularly for aromatic compounds. The complete nitrogen cycling was observed in both communities. The fungi in particular displayed pathways related to ammonification. Environmental stress response pathways were common among bacteria, whereas the nutrient stress response pathways were more widely present in bacteria, archaea and fungi. The diversity of bacterialphage was also surveyed by Geochip. Data suggested that different substrates supported different viral families: Leviviridae, Myoviridae, Podoviridae and Siphoviridiae were ubiquitous. However, Corticoviridae and Microviridae only occurred in wetter soils.

Keywords: Antarctica, hypolith, soil, dry valleys, geochip, functional diversity, stress response

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Authors: Hacer Kobya Bulut, Kıymet Yeşilçiçek Çalık, Birsel Canan Demirbağ, Hacer Erdöl, Songül Aktaş

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Introduction: As an expression of an emotion which always exists in life, crying is regarded as one of the problematic behaviors of patients by nurses. Towards such patients, nurses may exhibit emotional and behavioral reactions such as feeling helpless, anger, indifferent, defense, and opposition. However crying either meets a need, reduces the tension to cope with problems or helps patient to gain strength. Therefore, nurses must accept that crying is a normal mechanism that reduces emotional tension and should approach a crying patient accordingly. Objective: This study was carried out to evaluate the communicational behaviors of the nurses towards ‘crying patient’. Methods: This descriptive study was conducted with the nurses working at a university hospital in a city in the Eastern Black Sea in June-September 2015. The entire universe was tried to be reached without sampling. 90% of the population was reached and the study was completed with 309 nurses who volunteered to participate in the study. Data were collected through a questionnaire which was prepared reviewing the literature by researchers. Data were evaluated in SPSS analysis program using percentages, numbers and chi-square test with the 95% confidence interval and p <0.05significance level. Findings: The findings showed that the average age of nurses was 31.52 ± 7.96, work experience was 10:09 ± 7.69 and only 22.7% had training about ‘approach to crying patient’ during their education. 97.1% of the nurses often faced with crying patients in their professional lives, 62.8% stated that they faced crying women patients. When they see crying patients, 84.8% of the nurses ‘do not want the patient to cry’, 80.9% wonder ‘why they are crying’, % 79.6 ‘feel uneasiness’,% 79.3 ‘feel sorry’ and 41.4% ‘ feel helpless’. The question ‘Why do you think the patient is crying?’ was answered by 93.5% nurses as ‘they are suffering’, by 86.1% ‘they are helpless’, 80.9% ‘they are sad’, 79.6% ‘they need help’, 54.4% ‘because they feel inadequate,’ and 44.7% ‘they fail to control their crying behavior. ‘How do you approach to your patient when she/he is crying?’ question was answered by 82.5% of nurses as ‘I would console’, 77.3% as ‘I would ask the reason’, 63.1% as ‘I would try to stop her from crying’ all of which are actually inappropriate nursing approaches. However, 92.2% of the nurses stated that ‘I do not judge the crying patient’, ‘87.1% said ‘I allocate time to crying patients’ and 85.8% said ‘ I ask patient whether they want to cry alone’. The study showed that educational background and work experience of the nurses affected the appropriate approach to crying patients (P <0.05). Conclusion: As a result of the study, it was found out that nurses do not want patients to cry, so they exhibit inappropriate approach such as consoling the patients and they have difficulty in approaching crying patients.

Keywords: approach to patient, communication, crying patient, nurse, Turkey

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Authors: S. J. Matlan, M. Mukhlisin, M. R. Taha

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Characterization of the engineering behavior of unsaturated soil is dependent on the soil-water characteristic curve (SWCC), a graphical representation of the relationship between water content or degree of saturation and soil suction. A reasonable description of the SWCC is thus important for the accurate prediction of unsaturated soil parameters. The measurement procedures for determining the SWCC, however, are difficult, expensive, and time-consuming. During the past few decades, researchers have laid a major focus on developing empirical equations for predicting the SWCC, with a large number of empirical models suggested. One of the most crucial questions is how precisely existing equations can represent the SWCC. As different models have different ranges of capability, it is essential to evaluate the precision of the SWCC models used for each particular soil type for better SWCC estimation. It is expected that better estimation of SWCC would be achieved via a thorough statistical analysis of its distribution within a particular soil class. With this in view, a statistical analysis was conducted in order to evaluate the reliability of the SWCC prediction models against laboratory measurement. Optimization techniques were used to obtain the best-fit of the model parameters in four forms of SWCC equation, using laboratory data for relatively coarse-textured (i.e., sandy) soil. The four most prominent SWCCs were evaluated and computed for each sample. The result shows that the Brooks and Corey model is the most consistent in describing the SWCC for sand soil type. The Brooks and Corey model prediction also exhibit compatibility with samples ranging from low to high soil water content in which subjected to the samples that evaluated in this study.

Keywords: soil-water characteristic curve (SWCC), statistical analysis, unsaturated soil, geotechnical engineering

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Authors: Robert G. Nini

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Soil consolidation is one of the biggest problem facing engineers. The consolidation process has an important role in settlement analysis for the embankments and footings resting on clayey soils. The settlement amount is related to the compression and the swelling indexes of the soil. Because the predominant upper soil layer in Lebanon is consisting mainly of clay, this layer is a real challenge for structural and highway engineering. To determine the effect of load and drainage on the engineering consolidation characteristics of Lebanese soil, a full experimental and synthesis study was conducted on different soil samples collected from many locations. This study consists of two parts. During the first part which is an experimental one, the Proctor test and the consolidation test were performed on the collected soil samples. After it, the identifications soil tests as hydrometer, specific gravity and Atterberg limits are done. The consolidation test which is the main test in this research is done by loading the soil for some days then an unloading cycle was applied. It takes two weeks to complete a typical consolidation test. Because of these reasons, during the second part of our research which is based on the analysis of the experiments results, some correlations were found between the main consolidation parameters as compression and swelling indexes with the other soil parameters easy to calculate. The results show that the compression and swelling indexes of Lebanese clays may be roughly estimated using a model involving one or two variables in the form of the natural void ratio and the Atterberg limits. These correlations have increasing importance for site engineers, and the proposed model also seems to be applicable to a wide range of clays worldwide.

Keywords: atterberg limits, clay, compression and swelling indexes, settlement, soil consolidation

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Authors: William Thomas Worster

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This paper will highlight the failure of international adjudication to prevent a state from evading an order of provisional measures by simply issuing a diplomatic assurance to the court. This practice changes the positions of the litigants as equals before a court, prevents the court from inquiring into the reliability of the political pledge as it would with assurances from a state to an individual, and diminishes the court’s ability to control its own proceedings in the face of concerns over sovereignty. Both the European Court of Human Rights (ECtHR) and International Court of Justice (ICJ) will entertain these kinds of unilateral pledges, but they consider them differently when the declaration is made between states or between a state and an individual, and when made directly to the court. In short, diplomatic assurances issued between states or to individuals are usually considered not to be legally binding and are essentially questions of fact, but unilateral assurances issued directly to an international court are questions of law, and usually legally binding. At the same time, orders for provisional measures are now understood also to be legally binding, yet international courts will sometimes permit a state to substitute an assurance in place of an order for provisional measures. This emerging practice has brought the nature of a state as a sovereign capable of creating legal obligations into the forum of adjudication where the parties should have equality of arms and permitted states to create legal obligations that escape inquiry into the reliability of the outcome. While most recent practice has occurred at the ICJ in state-to-state litigation, there is some practice potentially extending the practice to human rights courts. Especially where the litigants are factually unequal – a state and an individual – this practice is problematic since states could more easily overcome factual failings in their pledges and evade the control of the court. Consider, for example, the potential for evading non-refoulement obligations by extending the current diplomatic assurances practice from the state-to-state context to the state-to-court context. The dual nature of assurances, as both legal and factual instruments, should be considered as addressed to distinct questions, each with its own considerations, and that we need to be more demanding about their precise legal and factual effects.

Keywords: unilateral, diplomacy, assurances, undertakings, provisional measures, interim measures

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Authors: Saad M. Howladar

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Although, there are a little data on the use of littoral plants as heavy metals bioaccumulators over large areas of the wetlands environment. So, soil samples and biomass of the five plant species: Pluchea dioscroides, Pulicaria crispa, Lavandula pubescens, Tarchononthus comporatus and Argemone ochroleuca were collected from two different sites (basin and mouth) of four dams at Baha province, KSA. Nutrients and heavy metals were extracted from plant samples (leaves and stems) for analyzing elements (Na, K, Ca, P and N) and heavy metals (Pb, Cu and Ni). The soils of the mouth of the dam had the highest concentrations of all elements, while that of basin had the highest ones of most heavy metals except Pb. The soil elements in relation to the two sites arranged as: Ca > K > P > Na > N; and the heavy metals as: Cu > Ni > Pb. The present study indicated that Pluchea dioscroides had the highest values of most elements and heavy metals, while Lavandula pubescens had the lowest. In general, leaves attain the highest concentrations of all nutrients and heavy metals in most studied species as compared with stem. It was indicated that Pluchea dioscroides showed a high transfer factor for almost elements and heavy metals such as K, Na, Cu, Ni and Pb, while Pulicaria crispa showed the highest translocation factor of N, P, Ca-Na ratio and Cu. All studied species growing in the basin had almost the highest concentrations of elements and heavy metals as compared with that in the mouth of dam except K in Pluchea dioscroides, Tarchononthus comporatus and Argemone ochroleuca tissues. Otherwise tissues of Tarchononthus comporatus growing in the basin had the lowest concentrations of K and Ni, while that growing in the mouth had the highest of P and N.

Keywords: Baha Region, bioindicators, plant, pollution, dams, heavy metals

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Authors: Flavio Gazzani

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Nitrogen is an important agricultural input that is critical for the production. However, the introduction of large amounts of nitrogen into the environment has a number of undesirable impacts such as: the loss of biodiversity, eutrophication of waters and soils, drinking water pollution, acidification, greenhouse gas emissions, human health risks. It is a challenge to sustain or increase food production and at the same time reduce losses of reactive nitrogen to the environment, but there are many potential benefits associated with improving nitrogen use efficiency. Reducing nutrient losses from agriculture is crucial to the successful implementation of agricultural policy. Traditional regulatory instruments applied to implement environmental policies to reduce environmental impacts from nitrogen fertilizers, despite some successes, failed to address many environmental challenges and imposed high costs on the society to achieve environmental quality objectives. As a result, economic instruments started to be recognized for their flexibility and cost-effectiveness. The objective of the research project is to analyze the potential for increased use of market-based instruments in nitrogen control policy. The report reviews existing knowledge, bringing different studies together to assess the global nitrogen situation and the most relevant environmental management policy that aims to reduce pollution in a sustainable way without affect negatively agriculture production and food price. This analysis provides some guidance on how different market based instruments might be orchestrated in an overall policy framework to the development and assessment of sustainable nitrogen management from the economics, environmental and food security point of view.

Keywords: nitrogen emissions, chemical fertilizers, eutrophication, non-point of source pollution, dairy farm

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Authors: Recep Kesli, Gulsah Asik, Cengiz Demir, Onur Turkyilmaz

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Objective: Stenotrophomonas maltophilia (S. maltophilia) has recently emerged as an important nosocomial microorganism. Treatment of invasive infections caused by this organism is problematic because this microorganism is usually resistant to a wide range of commonly used antimicrobials. We aimed to evaluate clinical isolates of S. maltophilia in respect to sampling sites and antimicrobial resistant. Method: During a two years period (October 2013 and September 2015) eighteen samples collected from the intensive care unit (ICU) patients hospitalized in Afyon Kocatepe University, ANS Practice and Research Hospital. Identification of the bacteria was determined by conventional methods and automated identification system-VITEK 2 (bio-Mérieux, Marcy l’toile, France). Antibacterial resistance tests were performed by Kirby Bauer disc (Oxoid, England) diffusion method following the recommendations of CLSI. Results: Eighteen S. maltophilia strains were identified as the causative agents of different infections. The main type of infection was lower respiratory tract infection (83,4 %); three patients (16,6 %) had bloodstream infection. While, none of the 18 S. maltophilia strains were found to be resistant against to trimethoprim sulfametaxasole (TMP-SXT) and levofloxacine, eight strains 66.6 % were found to be resistant against ceftazidim. Conclusion: The isolation of S.maltophilia starains resistant to TMP-SXT is vital. In order to prevent or minimize infections due to S. maltophilia such precuations should be utilized: Avoidance of inappropriate antibiotic use, prolonged implementation of foreign devices, reinforcement of hand hygiene practices and the application of appropriate infection control practices. Microbiology laboratories also may play important roles in controlling S. maltophilia infections by monitoring the prevalence, continuously, the provision of local antibiotic resistance paterns data and the performance of synergistic studies also may help to guide appropirate antimicrobial therapy choices.

Keywords: Stenotrophomonas maltophilia, trimethoprim-sulfamethoxazole, antimicrobial resistance, Stenotrophomonas spp.

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Authors: Ali Rahnamoun, Adri van Duin

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The concept of high velocity particle impact on the spacecraft surface materials has been one of the important issues in the design of such materials. Among these particles, water clusters might be the most abundant and the most important particles to be studied. The importance of water clusters is that upon impact on the surface of the materials, they can cause damage to the material and also if they are sub-cooled water clusters, they can attach to the surface of the materials and cause ice accumulation on the surface which is very problematic in spacecraft and also aircraft operations. The dynamics of the collisions between amorphous silica structures and water clusters with impact velocities of 1 km/s to 10 km/s are studied using the ReaxFF reactive molecular dynamics simulation method. The initial water clusters include 150 water molecules and the water clusters are collided on the surface of amorphous fully oxidized and suboxide silica structures. These simulations show that the most abundant molecules observed on the silica surfaces, other than reflecting water molecules, are H3O+ and OH- for the water cluster impacts on suboxide and fully oxidized silica structures, respectively. The effect of impact velocity on the change of silica mass is studied. At high impact velocities the water molecules attach to the silica surface through a chemisorption process meaning that water molecule dissociates through the interaction with silica surface. However, at low impact velocities, physisorbed water molecules are also observed, which means water molecule attaches and accumulates on the silica surface. The amount of physisorbed waters molecules at low velocities is higher on the suboxide silica surfaces. The evolution of the temperatures of the water clusters during the collisions indicates that the possibility of electron excitement at impact velocities less than 10 km/s is minimal and ReaxFF reactive molecular dynamics simulation can predict the chemistry of these hypervelocity impacts. However, at impact velocities close to 10 km/s the average temperature of the impacting water clusters increase to about 2000K, with individual molecules oocasionally reaching temperatures of over 8000K and thus will be prudent to consider the concept of electron excitation at these higher impact velocities which goes beyond the current ReaxFF ability.

Keywords: spacecraft materials, hypervelocity impact, reactive molecular dynamics simulation, amorphous silica

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Authors: Szilvia Várallyay, Béla Kovács, Éva Bódi, Farzeneh Garousi, Szilvia Veres

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Arsenic (As) is a naturally occurring substance that can be present in soil, water and air. Vegetables, fruits, and other plants that grow in contaminated soils which are able to accumulate arsenic. Arsenic when presents in plant cells, has various negative physiological effects and when presents in soil will be inorgaic form, namely arsenite (As(III)) and arsenate (As(V)). These two forms of arsenic disrupt plant metabolism by inhibiting its growth and these arsenic species has negative effect on nutrient uptake. A rhizobox experiment was conducted to investigate the effect of arsenite and arsenate on root growth of sunflower seedlings. Sunflower plants were grown in climatic room under irradiance of 300 µmol m-2 s-1, 16-h day and 8-h night photoperiod, day/night temperature of 25/20°C and relative humidity of 65-75%. We applied arsenic in form of arsenite (NaAsO2) and arsenate (KH2AsO4), respectively. The applied arsenic treatments was 0, 10, 30, 90 mg.kg-1. After disinfection, seeds were germinated between moist filter papers. Seedlings with 2-3 cm coleoptils were placed into rhizoboxes. In the rhizoboxes the growing and daily growing rhythm of roots of sunflower can be followed up, moreover possible phytotoxic symptoms of roots resulting from increasing arsenic can be seen. Weights of rhizoboxes were measured daily and also evaporated water added each day. The lengths of roots were measured daily until seedlings roots get at the end of the rhizoboxes. Negative correlation was observed between the higher concentration of arsenic in the soil and the growth of sunflower seedlings roots. The effect of arsenic toxicity was more considerable in 90 mg.kg-1 arsenic treatment than lower concentration. The same arsenite concentration causes slower growth in case of sunflower plant than the same arsenate concentration produced.

Keywords: arsenic, rhizobox experiment, sunflower, root growth

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Authors: Mitsuo Yoshida

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A significant mercury contamination of soil/sediment was unveiled by an environmental monitoring program in a wetland along La Plata River, west to Montevideo City, Uruguay. The mercury contamination was caused by industrial wastewater discharged from a chlor-alkali plant using a mercury-cell process. The contamination level is above 60 mg/kg in soil/sediment. Most of mercury (Hg) in the environment is inorganic, but some fractions are converted by bacteria to methylmercury (MeHg), a toxic organic compound. MeHg biologically accumulates through a food-chain and become serious public health risk. In order to clarify the contaminated part for countermeasure operation, an intervention value of mercury contamination of sediment/soil was defined as 15 mg/kg (total Hg) by the authority. According to the intervention value, mercury contaminated area in the La Plata site is approximately 48,280 m² and estimated total volume of contaminated sediments/soils was around 18,750 m³. The countermeasures to contaminated zone were proposed in two stages; (i) mitigation of risks for public health and (ii) site remediation. The first stage is an installation of fens and net around the contamination zone, for mitigating risks of exposure, inhalation, and intake. The food chain among wetland-river ecosystem was also interrupted by the installation of net and fens. The state of mercury contamination in La Plata site and plan of countermeasure was disclosed to local people and the public, and consensus on setting off-limit area was successfully achieved. Mass media also contribute to share the information on the contamination site. The cost for countermeasures was borne by the industry under the polluter-pay-principle.

Keywords: chlor-alkali plant, mercury contamination, polluter pay principle, Uruguay, wetland

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Authors: Biruhi Tesfaye, Avinash M. Potdar

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The laboratory test process to determine the California bearing ratio (CBR) of black cotton soils is not only overpriced but also time-consuming as well. Hence advanced prediction of CBR plays a significant role as it is applicable In pavement design. The prediction of CBR of treated soil was executed by Artificial Neural Networks (ANNs) which is a Computational tool based on the properties of the biological neural system. To observe CBR values, combined eggshell and waste glass was added to soil as 4, 8, 12, and 16 % of the weights of the soil samples. Accordingly, the laboratory related tests were conducted to get the required best model. The maximum CBR value found at 5.8 at 8 % of eggshell waste glass powder addition. The model was developed using CBR as an output layer variable. CBR was considered as a function of the joint effect of liquid limit, plastic limit, and plastic index, optimum moisture content and maximum dry density. The best model that has been found was ANN with 5, 6 and 1 neurons in the input, hidden and output layer correspondingly. The performance of selected ANN has been 0.99996, 4.44E-05, 0.00353 and 0.0067 which are correlation coefficient (R), mean square error (MSE), mean absolute error (MAE) and root mean square error (RMSE) respectively. The research presented or summarized above throws light on future scope on stabilization with waste glass combined with different percentages of eggshell that leads to the economical design of CBR acceptable to pavement sub-base or base, as desired.

Keywords: CBR, artificial neural network, liquid limit, plastic limit, maximum dry density, OMC

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Authors: Hojjat Mohammadi, Randall Divito, Gary J. E. Kramer

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Tunnelling and pipe jacking in very soft soils (fat clays), even with an Earth Pressure Balance tunnel boring machine (EPBM), can cause large ground displacements. In this study, the short-term and long-term ground and tunnel response is predicted for twin, pipe-jacked EPBM 3 meter diameter tunnels with a narrow pillar width. Initial modelling indicated complete closure of the annulus gap at the tail shield onto the centrifugally cast, glass-fiber-reinforced, polymer mortar jacking pipe (FRP). Numerical modelling was employed to simulate the excavation and support installation sequence, examine the ground response during excavation, confirm the adequacy of the pillar width and check the structural adequacy of the installed pipe. In the numerical models, Mohr-Coulomb constitutive model with the effect of unloading was adopted for the fat clays, while for the bedrock layer, the generalized Hoek-Brown was employed. The numerical models considered explicit excavation sequences and different levels of ground convergence prior to support installation. The well-studied excavation sequences made the analysis possible for this study on a very soft clay, otherwise, obtaining the convergency in the numerical analysis would be impossible. The predicted results indicate that the ground displacements around the tunnel and its effect on the pipe would be acceptable despite predictions of large zones of plastic behaviour around the tunnels and within the entire pillar between them due to excavation-induced ground movements.

Keywords: finite element modeling (FEM), pipe-jacked tunneling, very soft clay, EPBM

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Authors: Menna Brown, Tania Domun

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Digital health interventions are effective across a wide array of health conditions spanning physical health, lifestyle behaviour change, and mental health and wellbeing; furthermore, they are rapidly increasing in volume within both the academic literature and society as commercial apps continue to proliferate the digital health market. However, adherence and engagement to digital health interventions remains problematic. Technology-based personalised and tailored reminder strategies can support engagement to digital health interventions. Interventions which support individuals’ mental health and wellbeing are of critical importance in the wake if the COVID-19 pandemic. Student and young person’s mental health has been negatively affected and digital resources continue to offer cost effective means to address wellbeing at a population level. Develop a databank of digital co-produced tailored messages to support engagement to a range of digital health interventions including those focused on mental health and wellbeing, and lifestyle behaviour change. Qualitative research design. Participants discussed their views of health and wellbeing, engagement and adherence to digital health interventions focused around a 12-week wellbeing intervention via a series of focus group discussions. They worked together to co-create content following a participatory design approach. Three focus group discussions were facilitated with (n=15) undergraduate students at one Welsh university to provide an empirically derived, co-produced, databank of (n=145) tailored messages. Messages were explored and categorised thematically, and the following ten themes emerged: Autonomy, Recognition, Guidance, Community, Acceptance, Responsibility, Encouragement, Compassion, Impact and Ease. The findings provide empirically derived, co-produced tailored messages. These have been made available for use, via ‘ACTivate your wellbeing’ a digital, automated, 12-week health and wellbeing intervention programme, based on acceptance and commitment therapy (ACT). The purpose of which is to support future research to evaluate the impact of thematically categorised tailored messages on engagement and adherence to digital health interventions.

Keywords: digital health, engagement, wellbeing, participatory design, positive psychology, co-production

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Authors: Alan T. Sassler

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Biofouling is a significant issue for ships, especially those based in warm water ports. Biofouling damages hull coatings, degrades platform hydrodynamics, blocks cooling water intakes, and returns, reduces platform range and speed, and increases fuel consumption. Although platforms are protected to some degree by antifouling paints, these paints are much less effective on stationary platforms, and problematic biofouling can occur on antifouling paint-protected stationary platforms in some environments in as little as a matter of weeks. Remediation hull cleaning operations are possible, but they are very expensive, sometimes result in damage to the vessel’s paint or hull and are generally not completely effective. Ultrasound with sufficient intensity focused on specific frequency ranges can be used to prevent the growth of biofouling organisms. The use of ultrasound to prevent biofouling isn't new, but systems to date have focused on protecting platforms by shaking the hull using internally mounted transducers similar to those used in ultrasonic cleaning machines. While potentially effective, this methodology doesn't scale well to large platforms, and there are significant costs associated with installing and maintaining these systems, which dwarf the initial purchase price. An alternative approach has been developed, which uses highly directional pier-mounted transducers to project high-intensity spread-spectrum ultrasonic energy into the water column focused near the surface. This focused energy has been shown to prevent biofouling at ranges of up to 50 meters from the source. Spreading the energy out over a multi-kilohertz band makes the system both more effective and more environmentally friendly. This system has been shown to be both effective and inexpensive in small-scale testing and is now being characterized on a larger scale in selected marinas. To date, test results have been collected in Florida marinas suggesting that this approach can be used to keep ensonified areas of thousands of square meters free from biofouling, although care must be taken to minimize shaded areas.

Keywords: biofouling, ultrasonic, environmentally friendly antifoulant, marine protection, antifouling

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Authors: Toshikee Yadav, Deepti Tikariha, Jyotsna Lakra, Kallol K. Ghosh

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Polycyclic aromatic hydrocarbons (PAHs) are potent atmospheric pollutants that consist of two or more benzene rings. PAHs have low solubility in water. Their slow dissolution can contaminate large amounts of ground water for long period. They are hydrophobic, non-polar and neutral in nature and are known to have potential mutagenic or carcinogenic activity. In current scenario their removal from the environment, water and soil is still a great challenge and scientists worldwide are engaged to invent and design novel separation technology and decontaminating systems. Various physical, chemical, biological and their combined technologies have been applied to remediate organic-contaminated soils and groundwater. Surfactants play a vital role in the solubilization of these hydrophobic organic compounds. In the present investigation Solubilization capabilities of structurally different gemini surfactants i.e. butanediyl-1,4-bis(dimethyldodecylammonium bromide) (C12-4-C12,2Br−), 2-butanol-1,4-bis (dimethyldodecylammonium bromide) (C12-4(OH)-C12,2Br−), 2,3-butanediol-1,4-bis (dimethyldodecylammonium bromide) (C12-4(OH)2-C12,2Br−) for three polycyclic aromatic hydrocarbons (PAHs); phenanthrene (Phe),fluorene (Fluo) and acenaphthene (Ace) have been studied spectrophotometrically at 300 K. The result showed that the solubility of PAHs increases linearly with increasing surfactant concentration, as an implication of association between the PAHs and micelles. Molar solubilization ratio (MSR), micelle–water partition coefficient (Km) and Gibb's free energy of solubilization (ΔG°s) for PAHs have been determined in aqueous medium. (C12-4(OH)2-C12,2Br−) shows the higher solubilization for all PAHs. Findings of the present investigation may be useful to understand the role of appropriate surfactant system for the solubilization of toxic hydrophobic organic compounds.

Keywords: gemini surfactant, molar solubilization ratio, polycyclic aromatic hydrocarbon, solubilization

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Authors: D. A. S. Gamage, B. F. A. Basnayake, W.A.J.M. De Costa

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Rice is the staple food of Sri Lankans thus; rice cultivation is the major agricultural activity of the country. The application of inorganic fertilizer has become a burden to the country. The excessive application of organic and inorganic fertilizers can potentially lead to deterioration of the quality of water. In mixing both urea and rice husk charcoal and rice straw compost in soils causes a slow release of nitrogen fertilizer, thus reducing the cost of importations of nitrogen based fertilizers per unit area of cultivation. Objective of this study was to evaluate rice husk charcoal coated urea as a slow releasing fertilizer and compare the total N,P, K, organic matter in soil and yield of rice production. Five treatments were used for twenty pots (pot size 30 cm diameter and 45 cm height) each replicated four times as: inorganic fertilizer only (Urea, TSP and MOP) (Treatment 1); rice husk charcoal coated urea, TSP and MOP (Treatment 2); inorganic fertilizer (Urea, TSP and MOP) with rice straw compost only (Treatment 3); rice husk charcoal urea, TSP and MOP with rice straw compost (Treatment 4); and no fertilizer as the control (Treatment 5). Rice grain yield was significantly higher in treatment 4 where rice husk charcoal coated urea, TSP and MOP with rice straw compost. The lowest yield was observed in control (treatment 5). The lower the value of the nitrogen to phosphorous ratio in soil, it indicates higher uptake of phosphorous. Charcoal can be used as a soil amendment and organic fertilizer, but adjustment of pH was required at high application rates. K content of soil of treatment 3 and 4 were the highest with compared to the treatment 1. Rice husk charcoal coated urea can potentially be used as a slow releasing nitrogen fertilizer.

Keywords: charcoal, rice husk, nitrogen to phosphorous ratio, soil amendment

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Authors: Vivian A. Galindo, Maria C. Galvis, Jaime R. Obando, Alvaro Guarin

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In Colombia, most of the roads of the national tertiary road network are unpaved roads with granular rolling surface. These are very important ways of guaranteeing the mobility of people, products, and inputs from the agricultural sector from the most remote areas to urban centers; however, it has not paid much attention to the search for alternatives to avoid the occurrence of deteriorations that occur shortly after its commissioning. In recent years, geosynthetics have been used satisfactorily to reinforce unpaved roads on soft soils, with geotextiles and geogrids being the most widely used. The interaction of the geogrid and the aggregate minimizes the lateral movement of the aggregate particles and increases the load capacity of the material, which leads to a better distribution of the vertical stresses, consequently reducing the vertical deformations in the subgrade. Taking into account the above, the research aimed at the mechanical behavior of the granular material, used in unpaved roads with and without the presence of geogrids, from the development of laboratory tests through the loaded wheel tester (LWT). For comparison purposes, the reinforced conditions and traffic conditions to which this type of material can be accessed in practice were simulated. In total four types of geogrids, were tested with granular material; this means that five test sets, the reinforced material and the non-reinforced control sample were evaluated. The results of the numbers of load cycles and depth rutting supported by each test body showed the influence of the properties of the reinforcement on the mechanical behavior of the assembly and the significant increases in the number of load cycles of the reinforced specimens in relation to those without reinforcement.

Keywords: geosynthetics, load wheel tester LWT, tertiary roads, unpaved road, vertical deformation

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Authors: Pieter A. Cornelissen, Joris J. Van Hoof

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The interest in improving occupational safety started almost simultaneously with the beginning of the Industrial Revolution. Yet, it was not until the late 1970’s before the role of communication was considered in scientific research regarding occupational safety. In recent years the importance of communication as a means to improve occupational safety has increased. Not only as communication might have a direct effect on safety performance and safety outcomes, but also as it can be viewed as a major component of other important safety-related elements (e.g., training, safety meetings, leadership). And while safety communication is an increasingly important topic in research, its operationalization is often vague and differs among studies. This is not only problematic when comparing results, but also in applying these results to practice and the work floor. By means of an in-depth analysis—building on an existing dataset—this review aims to overcome these problems. The initial database search yielded 25.527 articles, which was reduced to a research corpus of 176 articles. Focusing on the 37 articles of this corpus that addressed communication (related to safety outcomes and safety performance), the current study will provide a comprehensive overview of the role and effects of safety communication and outlines the conditions under which communication contributes to a safer work environment. The study shows that in literature a distinction is commonly made between safety communication (i.e., the exchange or dissemination of safety-related information) and feedback (i.e. a reactive form of communication). And although there is a consensus among researchers that both communication and feedback positively affect safety performance, there is a debate about the directness of this relationship. Whereas some researchers assume a direct relationship between safety communication and safety performance, others state that this relationship is mediated by safety climate. One of the key findings is that despite the strongly present view that safety communication is a formal and top-down safety management tool, researchers stress the importance of open communication that encourages and allows employees to express their worries, experiences, views, and share information. This raises questions with regard to other directions (e.g., bottom-up, horizontal) and forms of communication (e.g., informal). The current review proposes a framework to overcome the often vague and different operationalizations of safety communication. The proposed framework can be used to characterize safety communication in terms of stakeholders, direction, and characteristics of communication (e.g., medium usage).

Keywords: communication, feedback, occupational safety, review

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Authors: Omer Altaf, Liam Wotherspoon, Rolando Orense

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The Wairau Plains are located in the north-east of the South Island of New Zealand in the region of Marlborough. The region is cut by many active crustal faults such as the Wairau, Awatere, and Clarence faults, which give rise to frequent seismic events. This paper presents the preliminary results of the overall project in which liquefaction-induced ground damage maps are developed in the Wairau Plains based on the Ministry of Business, Innovation and Employment NZ guidance. A suite of maps has been developed in relation to the level of details that was available to inform the liquefaction hazard mapping. Maps at the coarsest level of detail make use of regional geologic information, applying semi-quantitative criteria based on geological age, design peak ground accelerations and depth to the water table. The next level of detail incorporates higher resolution surface geomorphologic characteristics to better delineate potentially liquefiable and non-liquefiable deposits across the region. The most detailed assessment utilised CPT sounding data to develop ground damage response curves for areas across the region and provide a finer level of categorisation of liquefaction vulnerability. Linking these with design level earthquakes defined through NZGS guidelines will enable detailed classification to be carried out at CPT investigation locations, from very low through to high liquefaction vulnerability. To update classifications to these detailed levels, CPT investigations in geomorphic regions are grouped together to provide an indication of the representative performance of the soils in these areas making use of the geomorphic mapping outlined above.

Keywords: hazard, liquefaction, mapping, seismicity

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Authors: Constantin Haita

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The chalcolithic tell settlements from south-eastern Romania, attributed to Gumelnița culture, are characterised by a well-defined surface, marked often by delimitation structures, a succession of many layers of construction, destruction, and rebuilding, and a well-structured area of occupation: built spaces, passage areas, waste zones. Settlements of tell type are located in the river valleys –on erosion remnants, alluvial bars or small islands, at the border of the valleys– on edges or prominences of Pleistocene terraces, lower Holocene terraces, and banks of lakes. This study integrates data on the geographical position, the morphological background, and the general stratigraphy of these important settlements. The correlation of the spatial distribution with the geomorphological units of each area of evolution creates an image of the natural landscape in which they occurred. The sedimentological researches achieved in the floodplain area of Balta Ialomiței showed important changes in the alluvial activity of Danube, after the Chalcolithic period (ca. 6500 - 6000 BP), to Iron Age and Middle Ages. The micromorphological analysis, consisting in thin section interpretation, at the microscopic scale, of sediments and soils in an undisturbed state, allowed the interpretation of the identified sedimentary facies, in terms of mode of formation and anthropic activities. Our studied cases reflect some distinct situations, correlating either with the geomorphological background or with the vertical development, the presence of delimiting structures and the internal organization. The characteristics of tells from this area bring significant information about the human habitation of Lower Danube in Prehistory.

Keywords: chalcolithic, micromorphology, Romania, sedimentology, tell settlements

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Authors: Martin Tazky, Rudolf Hela, Lucia Osuska, Petr Novosad

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Concrete’s volumetric changes are natural process caused by silicate minerals’ hydration. These changes can lead to cracking and subsequent destruction of cementitious material’s matrix. In most cases, cracks can be assessed as a negative effect of hydration, and in all cases, they lead to an acceleration of degradation processes. Preventing the formation of these cracks is, therefore, the main effort. Once of the possibility how to eliminate this natural concrete shrinkage process is by using different types of dispersed reinforcement. For this application of concrete shrinking, steel and polymer reinforcement are preferably used. Despite ordinarily used reinforcement in concrete to eliminate shrinkage it is possible to look at this specific problematic from the beginning by itself concrete mix composition. There are many secondary raw materials, which are helpful in reduction of hydration heat and also with shrinkage of concrete during curing. The new science shows the possibilities of shrinkage reduction also by the controlled formation of hydration products, which could act by itself morphology as a traditionally used dispersed reinforcement. This contribution deals with the possibility of controlled formation of mono- and tri-sulfate which are considered like degradation minerals. Mono- and tri- sulfate's controlled formation in a cementitious composite can be classified as a self-healing ability. Its crystal’s growth acts directly against the shrinking tension – this reduces the risk of cracks development. Controlled formation means that these crystals start to grow in the fresh state of the material (e.g. concrete) but stop right before it could cause any damage to the hardened material. Waste materials with the suitable chemical composition are very attractive precursors because of their added value in the form of landscape pollution’s reduction and, of course, low cost. In this experiment, the possibilities of using the fly ash from fluidized bed combustion as a mono- and tri-sulphate formation additive were investigated. The experiment itself was conducted on cement paste and concrete and specimens were subjected to a thorough analysis of physicomechanical properties as well as microstructure from the moment of mixing up to 180 days. In cement composites, were monitored the process of hydration and shrinkage. In a mixture with the used admixture of fluidized bed combustion fly ash, possible failures were specified by electronic microscopy and dynamic modulus of elasticity. The results of experiments show the possibility of shrinkage concrete reduction without using traditionally dispersed reinforcement.

Keywords: shrinkage, monosulphates, trisulphates, self-healing, fluidized fly ash

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Authors: Esra Ceren Kara, Ufuk Seri̇n

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The Byzantine Empire, which persisted from the 4th to 15th centuries, covered a significant period in history and bequeathed a significant cultural heritage throughout its territories, including Turkey. However, despite its historical and cultural importance, the approach of the political authorities, which emphasizes the Seljuk and Ottoman heritage, to Byzantium in Turkey is reluctant and problematic. Byzantine history and culture have long been neglected and attained negative connotations. This has led to a lack of awareness and understanding of Byzantine heritage among the public and inadequate conservation efforts. This research aims to address this problem by proposing a reinterpretation and presentation of Byzantine heritage in Turkey that emphasizes its cultural value and presents it to the public as a part of a common cultural heritage in order to accomplish effective conservation, raise awareness and provide a better understanding of the Byzantium. In this article, the ways to interpret, present and integrate the Medieval Byzantine heritage into today’s world are analyzed through the selected case study of Trebizond (Trabzon) with a holistic approach by putting emphasis on the Byzantine religious edifices, churches, chapels and monasteries. Although the vestiges of this period are still intact and in use today, their past is unknown to many of their users. This situation is even more evident in the case of the converted churches, which are now used as mosques or mosque-museums. In the city center of Trebizond, 9 out of 12 religious edifices that are still in use were built during the Medieval Byzantine period and converted into mosques under Ottoman and Turkish rule. Currently, these monuments serve as mosques and mosque-museums. However, with the exception of Hagia Sophia and Girls Monastery, their Byzantine past is obscure to many locals. Thus, the promotion of local awareness and conservation of the Medieval Byzantine heritage in the city is required. With this premise, this research will investigate the values and opportunities offered by the Byzantine cultural heritage in Trebizond and the threats to its conservation, and it will offer proposals for a more effective interpretation and presentation so as to foster local awareness and integration of the Medieval Byzantine heritage.

Keywords: Byzantium/Byzantine, Trebizond, cultural heritage, interpretation and presentation, conservation, religious architecture, converted churches interpretation and presentation

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Authors: Ume Habiba, Shafaqat Ali, Mujahid Farid, Muhammad Bilal Shakoor

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Copper (Cu) is an essential micronutrient for normal plant growth and development, but in excess, it is also toxic to plants. The present study investigated the influence of ethylenediaminetetraacetic acid (EDTA) in enhancing Cu uptake and tolerance as well as the morphological and physiological responses of Brassica napus L. seedlings under Cu stress. Four-week-old seedlings were transferred to hydroponics containing Hoagland’s nutrient solution. After 2 weeks of transplanting, three levels (0, 50, and 100 μM) of Cu were applied with or without application of 2.5 mM EDTA and plants were further grown for 8 weeks in culture media. Results showed that Cu alone significantly decreased plant growth, biomass, photosynthetic pigments, and gas exchange characteristics. Cu stress also reduced the activities of antioxidants, such as superoxide dismutase (SOD), peroxidase (POD), ascorbate peroxidase (APX), and catalase (CAT) along with protein contents. Cu toxicity increased the concentration of reactive oxygen species (ROS) as indicated by the increased production of malondialdehyde (MDA) and hydrogen peroxide (H2O2) in both leaves and roots. The application of EDTA significantly alleviated Cu-induced toxic effects in B. napus, showing remarkable improvement in all these parameters. EDTA amendment increased the activity of antioxidant enzymes by decreasing the concentrations of MDA and H2O2 both in leaves and roots of B. napus. Although, EDTA amendment with Cu significantly increased Cu uptake in roots, stems, and leaves in decreasing order of concentration but increased the growth, photosynthetic parameters, and antioxidant enzymes. These results showed that the application of EDTA can be a useful strategy for phytoextraction of Cu by B. napus from contaminated soils.

Keywords: antioxidants, biomass, copper, EDTA, phytoextraction, tolerance

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Authors: Parminder Kaur, Chandrajit B. Majumder

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The unrestrained usage of pesticides to meet the burgeoning demand of enhanced crop productivity has led to the serious contamination of both terrestrial and aquatic ecosystem. The remediation of mixture of pesticides is a challenging affair regarding inadvertent mixture of pesticides from agricultural lands treated with various compounds. Global concerns about the excessive use of pesticides have driven the need to develop more effective and safer alternatives for their remediation. We focused our work on the microbial degradation of a mixture of three Type II-pyrethroids, namely Cypermethrin, Cyhalothrin and Deltamethrin commonly applied for both agricultural and domestic purposes. The fungal strains (Fusarium strain 8-11P and Fusarium sp. zzz1124) had previously been isolated from agricultural soils and their ability to biotransform this amalgam was studied. In brief, the experiment was conducted in two growth systems (added carbon and carbon-free) enriched with variable concentrations of pyrethroids between 100 to 300 mgL⁻¹. Parameter optimization (pH, temperature, concentration and time) was done using a central composite design matrix of Response Surface Methodology (RSM). At concentrations below 200 mgL⁻¹, complete removal was observed; however, degradation of 95.6%/97.4 and 92.27%/95.65% (in carbon-free/added carbon) was observed for 250 and 300 mgL⁻¹ respectively. The consortium has been shown to degrade the pyrethroid mixture (300 mg L⁻¹) within 120 h. After 5 day incubation, the residual pyrethroids concentration in unsterilized soil were much lower than in sterilized soil, indicating that microbial degradation predominates in pyrethroids elimination with the half-life (t₁/₂) of 1.6 d and R² ranging from 0.992-0.999. Overall, these results showed that microbial consortia might be more efficient than single degrader strains. The findings will complement our current understanding of the bioremediation of mixture of Type II pyrethroids with microbial consortia and potentially heighten the importance for considering bioremediation as an effective alternative for the remediation of such pollutants.

Keywords: bioremediation, fungi, pyrethroids, soil

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Authors: Rishab Das, Arnab Banerjee, Bappaditya Manna

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Mono-pile foundations are often used in soft soils in order to support heavy mega-structures, whereby often these deep footings may undergo dynamic excitation due to many causes like earthquake, wind or wave loads acting on the superstructure, blasting, and unbalanced machines, etc. A comprehensive analytical study is performed to study the dynamics of the mono-pile system embedded in cohesion-less soil. The soil is considered homogeneous and visco-elastic in nature and is analytically modeled using complex springs. Considering the N number of the elements of the pile, the final global stiffness matrix is obtained by using the theories of the spectral element matrix method. Further, statically condensing the intermediate internal nodes of the global stiffness matrix results to a smaller sub matrix containing the nodes experiencing the external translation and rotation, and the stiffness and damping functions (impedance functions) of the embedded piles are determined. Proper plots showing the variation of the real and imaginary parts of these impedance functions with the dimensionless frequency parameter are obtained. The plots obtained from this study are validated by that provided by Novak,1974. Further, the dynamic analysis of the resonator impregnated pile is proposed within this study. Moreover, with the aid of Wood's 1g laboratory scaling law, a proper scaled-down resonator-pile model is 3D printed using PLA material. Dynamic analysis of the scaled model is carried out in the time domain, whereby the lateral loads are imposed on the pile head. The response obtained from the sensors through the LabView software is compared with the proposed theoretical data.

Keywords: mono-pile, visco-elastic, impedance, LabView

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Authors: Ashim Kanti Dey, Briti Sundar Bhowmik

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This paper presents an idea to improve the soft soil by using lime grits which are normally produced as waste product in the paper manufacturing industries. This waste material cannot be used as a construction material because of its light weight, uniform size and poor compaction control. With scarcity in land, effective disposal of lime grit is a major concern of all paper manufacturing industries. Considering its non-plasticity and high permeability characteristics the lime grit may suitably be used as a drainage material for speedy consolidation of cohesive soil. It can also be used to improve the bearing capacity of soft clay. An attempt has been made in this paper to show the usefulness of lime grit in improving the bearing capacity of shallow foundation resting on soft clayey soil. A series of undrained unconsolidated cyclic triaxial tests performed at different area ratios and at three different water contents shows that dynamic shear modulus and damping ratio can be substantially improved with lime grit. Improvement is observed to be more in case of higher area ratio and higher water content. Static triaxial tests were also conducted on lime grit reinforced clayey soil after application of 50 load cycles to determine the effect of lime grit columns on cyclically loaded clayey soils. It is observed that the degradation is less for lime grit stabilized soil. A study of model test with different area ratio of lime column installation is also included to see the field behaviour of lime grit reinforced soil.

Keywords: lime grit column, area ratio, shear modulus, damping ratio, strength ratio, improvement factor, degradation factor

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Authors: Magarò Floriana, Zinno Raffaele

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Since 2009, with the coming into force of the January 14, 2008 Ministerial Decree "New technical standards for construction", and the explanatory ministerial circular N°.617 of February 2, 2009, the question of seismic hazard and the design of seismic-resistant structures in Italy has acquired increasing importance. One of the most discussed aspects in recent Italian and international scientific literature concerns the dynamic interaction between land and structure, and the effects which dynamic coupling may have on individual buildings. In effect, from systems dynamics, it is well known that resonance can have catastrophic effects on a stimulated system, leading to a response that is not compatible with the previsions in the design phase. The method used in this study to estimate the frequency of oscillation of the structure is as follows: the analysis of HVSR (Horizontal to Vertical Spectral Ratio) relations. This allows for evaluation of very simple oscillation frequencies for land and structures. The tool used for data acquisition is an experimental digital tromograph. This is an engineered development of the experimental Languamply RE 4500 tromograph, equipped with an engineered amplification circuit and improved electronically using extremely small electronic components (size of each individual amplifier 16 x 26 mm). This tromograph is a modular system, completely "free" and "open", designed to interface Windows, Linux, OSX and Android with the outside world. It an amplifier designed to carry out microtremor measurements, yet which will also be useful for seismological and seismic measurements in general. The development of single amplifiers of small dimension allows for a very clean signal since being able to position it a few centimetres from the geophone eliminates cable “antenna” phenomena, which is a necessary characteristic in seeking to have signals which are clean at the very low voltages to be measured.

Keywords: microtremor, HVSR, tromograph, structural engineering

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Authors: Anna Jesionek, Aleksandra Szreniawa-Sztajnert, Zbigniew Jaremicz, Adam Kokotkiewicz, Natalia Filipowicz, Renata Ochocka, Bozena Zabiegala, Maria Luczkiewicz

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Rhododendron tomentosum (formerly Ledum palustre), an evergreen shrub grows in peaty soils in northern Europe, Asia and North America. In Poland, it is classified as an endangered species not only due to the drainage of wetlands, but also to the excessive collection of this repellent plant by human. The other valuable biological properties of R. tomentosum, used for years in folk medicine, include anti-inflammatory, analgesic and anti-microbial activity, conditioned by the essential oil content. Taking into account the importance of biodiversity and the potential therapeutic application, it was decided to establish, for the first time, the micropropagation protocol for R. tomentosum, for ex-situ conservation of this endangered species as well as to obtain the continuous source of in vivo and in-vitro plant material for further studies. This object was achieved by the selection of the explant and the media, which were modified within the scope of mineral composition, sugar content, pH and the growth regulators. As a result, the four-stage micropropagation protocol for R. tomentosum was specified, including shoot multiplication, elongation, rooting and ex-vitro adaptation. The genetic identification of the examined species and the compatibility of progeny plants with maternal ones was tested with molecular biology methods. Moreover, during the research process, the chemical composition of initial and regenerated plant and in vitro shoots was controlled in terms of volatile fraction by phytochemical analysis (GC and TLC methods). The correctness of the micropropagation procedure was confirmed by both types of studies.

Keywords: ex situ conservation, Ledum palustre, micropropagation, Rhododendron tomentosum

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Authors: Irina Mikajlo, Jakub Elbl, Helena Dvořáčková, Antonín Kintl, Jindřich Kynický, Martin Brtnický, Jaroslav Záhora

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Present work deals with the possible use of fertigation in agriculture and its impact on the availability of mineral nitrogen (Nmin) in topsoil and subsoil horizons. The aim of the present study is to demonstrate the effect of the organic matter presence in fertigation on microbial transformation and availability of mineral nitrogen forms. The main investigation reason is the potential use of pre-treated waste water, as a source of organic carbon (Corg) and residual nutrients (Nmin) for fertigation. Laboratory experiment has been conducted to demonstrate the effect of the arable land fertilization method on the Nmin availability in different depths of the soil with the usage of model experimental containers filled with soil from topsoil and podsoil horizons that were taken from the precise area. Tufted hairgrass (Deschampsia caespitosa) has been chosen as a model plant. The water source protection zone Brezova nad Svitavou has been a research area where significant underground reservoirs of drinking water of the highest quality are located. From the second half of the last century local sources of drinking water show nitrogenous compounds increase that get here almost only from arable lands. Therefore, an attention of the following text focuses on the fate of mineral nitrogen in the complex plant-soil. Research results show that the fertigation application with Corg in a combination with mineral fertilizer can reduce the amount of Nmin leached from topsoil horizon of agricultural soils. In addition, some plants biomass production reduce may occur.

Keywords: fertigation, fertilizers, mineral nitrogen, soil microorganisms

Procedia PDF Downloads 336