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Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
The use of constructed wetlands for the treatment of agro-industrial wastewater – A case study in a dairy-cattle farm in Sicily (Italy)
No full textWastewaters generated by agro-industrial operations often represent an unsustainable cost for farms due to high wastewater-treatment management costs. The wastewater produced by dairies, wineries or oil mills may vary in quantity and in quality depending on the time of the year, making the use of a conventional treatment system less efficient and more costly. Constructed wetland systems (CWs) provide low-cost technology and an efficient solution in the treatment of a number of wastewaters from agriculture. They are simple to build, have low maintenance costs and are sustainable compared to conventional treatment methods. This paper shows a case study that was carried out on a dairy-cattle farm, located in the West of Sicily (Italy). The aim of the study was to evaluate the pollutant removal efficiency of an horizontal subsurface flow system (HSSFs) for the treatment of dairy parlor wastewater (DWWs). An HSSFs was planted with Phragmitesaustralis (Cav.) Trin. ex Steud. DWWs were initially pre-treated with a degreaser and two Imhoff septic tanks were used for the removal of suspended solids. The results showed a significant removal rate of organic pollutants by the HSSFs. The system was efficient in the treatment of DWWs and represents an artificial engineering system that corresponds well to Italian legislation requirements concerning the management of agricultural wastewaters from dairy-cattle farms
Biostimulants Improve Plant Performance of Rosemary Growth in Agricultural Organic System
Full text linkRosemary (Rosmarinus officinalis L.) is an evergreen and a xerophytic shrub that is frequently employed in culinary, decorative, and industrial applications. It shows significant variations in biomass and essential oil (EO) yield due to effects of biotic and abiotic factors. Biostimulants are widely used in agriculture, and in organic agricultural systems, they may contribute significantly to the stability and/or to the increase in crop yields, ensuring respect for the environment. The aim of this study was to assess the effect of different types of biostimulants on the yield performance of rosemary. Four commercial formulations of biostimulants based on Eklonia maxima, Ascophyllum
nodosum, fulvic acids, and protein hydrolysates were used for the tests. Water was used as a control. Six applications were performed. At harvest, several morphological and productive parameters were determined. All parameters were affected by biostimulant application. The highest fresh and dry yields were obtained with the application of fulvic acids (13.1 t ha−1 of fresh biomass and 4.3 t ha−1 of dry biomass) and protein hydrolysates (13.6 t ha−1 of fresh biomass and 4.4 t ha−1 of dry biomass) with values 60% higher than that of the control. Regarding the EO content in the dry biomass, the highest value (1.72% v/w) was found in control plants, whilst the lowest (1.14%) was observed in
plants treated with fulvic acids. In the case of the EO yield, the lowest value (46.5 kg ha−1) per unit area was found in the control. The application of Eklonia maxima and protein hydrolysates produced the highest EO yield values, 65 kg ha−1 and 66.5 kg ha−1, respectively. This study highlights the use of biostimulants to increase the yield performance of rosemary when grown in an organic agricultural system
Agronomic evaluation of ethiopian mustard (Brassica carinata A. Braun) germplasm and physical-energy characterization of crop residues in a semi-arid area of sicily (Italy)
No full textBrassica carinata A. Braun is one of the most interesting oilseed crops suited to arid and semi-arid areas for energy purposes. Several studies have highlighted the possibility of introducing this species into cropping systems, typical of Mediterranean region. The aims of this study were to evaluate the agronomic performance of Brassica carinata germplasm under Mediterranean climatic conditions and to assess the physical and energy characteristics of crop residues and pellets made from the residues. A total of 20 different accessions of Brassica carinata were compared in a semi-arid area of Sicily (Italy). In the two-year test period, the main morphological and yield parameters of the accessions were recorded. Crop residues were characterized by determining the moisture content, the ash content and the gross calorific value. The crop residues were tested for pellet-making and the end product was analysed for its physical and energy properties by determining the ash content, gross calorific value and mechanical durability. For crop residues, differences were found to be highly significant for the moisture content and not significant for the gross calorific value. For pellet, differences were highly significant for all parameters in the study
Seasonal response of vegetation on pollutants removal in constructed wetland system treating dairy wastewater
Full text linkConstructed wetland systems provide the ideal solution for small and medium dairy farms as they can be built close to the farm and are easy to manage and use. However, their perfomance is significantly affected by vegetation activity during the year. The aims of the present study were to assess the treatment of dairy wastewater (DWW) by a horizontal subsurface flow system (HSSFs) and the effect of plants in the removal efficiency
(RE) of BOD5, COD, total N (TN) and total P (TP), in Sicily (Italy). The HSSFs treated 6/7 m3 per day of wastewater produced by a small dairy farm subsequent to biological treatment. The system included two units which were separately planted with Arundo donax L. and Cyperus alternifolius L. During a three-year study, the main chemical and microbiological characteristics were determined as well as pollutant RE. Plant growth analysis was carried out and biomass production was determined. All DWW parameters showed significant differences between inlet and outlet. In particular, for BOD5 and COD, average RE values were 77.8% and 61.6%, respectively. Arundo donax produced greater biomass than Cyperus alternifolius for both above- (4240.3 g m2/ year) and below-ground (6996.3 g m2/year) plant parts. A seasonal variation in RE of BOD5, COD, TN and TP was recorded due to plant growth rates. Our findings highlight that the contribution of plants in pollutant RE tends to vary seasonally
Constructed wetlands as nature-based solution for sustainable wastewater management in urban areas: a critical assessment by experimental studies and literature
No full textIn urban areas, constructed wetland systems (CWS) have been recognized as one of the most valid technologies for sustainable wastewater management. They represent green infrastructure and provide solutions to treatment of wastewaters that cities and peri-urban areas produce in large amount. In particular, CWS offer the advantages of wastewater reuse for parklands irrigation, water storage and peak-flow attenuation, control of stormwater runoff, nutrient cycling and uptake, heavy metals sequestration, removal of organic compounds. In greener cities, these systems have the potential to perform not just hydrological and wastewater treatment functions, but also urban design and ecological aspects as demonstrated by numerous applications around the world. CWS, in fact, can function as urban wildlife sites, educational or recreational facilities, landscape engineering and ecological areas. The aim of this paper was to highlight the potential functionality of CWS in urban areas by a critical assessment of two experimental studies and literature. In particular, the two studies were carried out in Sicily (Italy) in order to evaluate: i) the pollutant removal efficiency of two CWS to treat urban wastewater and first-flush stormwater; ii) the reuse of treated wastewater for irrigation of plants. The results confirm that CWS are efficient in the treatment and reuse of wastewater for irrigation purposes in modern cities. Furthermore, CWS showed very high organic pollutant removal and a good efficiency in reducing excess of nutrients and trace metals, highlighting their important role in the treatment of stormwater in urban areas
Management of irrigation water and nutrient demands of tomato (Lycopersicon esculentum Mill.) using urban treated wastewater from a pilot-scale horizontal subsurface flow system constructed wetland in Sicily (Italy)
No full textThe reuse of treated wastewater (TWW) in crop irrigation is an advanced and rational approach to water resource management in agriculture. Results would seem to demonstrate that it could be an extremely important tool in the reduction of freshwater (FW) consumption in agriculture, at the same time helping to increase crop yields through the transfer of nutrients required for crop growth. In arid and semi-arid areas of the Mediterranean, constructed wetlands can play a key role in the treatment and reuse of wastewater due to their multifunctional nature. The aim of this study was to manage water and nutrient requirements of tomato (Lycopersicon esculentum Mill.) using TWW from a pilot-scale horizontal subsurface flow system (HSSFs) in a comparative study with traditional agronomic management methods. Research was carried out in 2015 at a pilot-scale HSSFs test area in West Sicily. Tomato plant plots were irrigated with both FW and with TWW from 2 planted-units and an unplanted-unit. Results showed that the pilot system was efficient in the treatment of wastewater and FW saving was high: approx. 90 m3 of water per t of total tomato yield. The TWW affected the productive, biometric and qualitative parameters of the tomato fruits considerably. The increase in total tomato fruit yield using TWW compared to FW was found to be 4 t ha–1 regarding water from unit A, 6 t ha–1 from unit B, and 7 t ha–1 from unit C of the HSSFs. Escherichia coli concentrations were not always within the threshold limits required by Italian law concerning the reuse of TWW in irrigation. Maximum microbial contamination was found in the fruit skin (106 CFU 100 g–1 on average) and in those fruits which were in contact with bare soil. No significant variation of soil pH was found but an increase in organic matter content and salinity was recorded in TWW-irrigated plots. Results confirm that TWW can provide an additional source of water and fertilizer in areas where FW supply is limited
The use of constructed wetlands for the treatment and reuse of urban wastewater for the irrigation of two warm-season turfgrass species under Mediterranean climatic conditions
Full text linkConstructed wetlands (CWs) represent low-cost technology for the treatment and reuse of wastewater in urban areas. This study aimed to evaluate the pollutant removal efficiency of a CW system and to assess the effects of irrigation using treated urban wastewater on soil and on two warm-season turf species. The research was carried out in Sicily (Italy) on a pilot-scale horizontal subsurface flow system which was fed with treated urban wastewater following secondary treatment from an activated-sludge wastewater treatment plant. The pilot system was located in an open urban park and comprised two separate parallel planted units. Experimental fields of Cynodon dactylon (L.) Pers. and Paspalum vaginatum Sw. were set up close to the system and irrigated with both treated wastewater (TWW) and freshwater (FW). Irrigation with TWW did not result in a significant variation in soil pH and soil salinity in the topsoil. The turf species tolerated high sodium levels in the soil due to TWW irrigation. Savings in FW and mineral fertilizers were deemed significant. The results highlight the fact that use of CW systems for the treatment and reuse of wastewater can represent a sustainable way to obtain alternative water resources for turfgrass irrigation in urban areas
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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