A low environmental impact system for fertirrigation of maize with cattle slurry

The applicability of an alternative system for managing and distributing cattle slurry during irrigation on maize was evaluated. An experiment was carried out by equipping a traveller boom with drop tubes and fed from a hose-reel machine. The new system was used for the distribution of the liquid separated fraction of slurry mixed with irrigation water (fertigation) on the soil surface between the rows of the crop. This system was compared with the conventional management system, utilizing a tank wagon equipped with splash plate for slurry application and a fixed irrigation system for irrigation. Analysis on leaching water samples indicate that the quality of percolation water is better due to a reduction in nitrate nitrogen losses. Besides, this alternative technique reduces the emissions of ammonia in the air and consequently the diffusion of ammonia in the atmosphere

Effect of seed-beds on the cultivation of Radicchio (Cichorium intybus L., Rubifolium group)

The use of raised beds (i.e., ridged soil layers) to cultivate vegetables can improve soil quality, crop performance, water use and even reduce soil erosion. Although those advantages are well known and documented in the literature for many vegetable species, Radicchio, a particular variety of chicory, is usually cultivated in flat seed-beds and, therefore, the achievable benefits of raised beds for this vegetable are not yet known. The possibility to grow plants of Radicchio on raised beds is here evaluated by comparing the most important yield performances indicators deriving from the adoption of this practice (grown plants percentage, average head weight, marketable yields, and net incomes) with the same indicators recorded with a conventional practice making use of flat seed-beds. The results evidenced that raised beds for Radicchio had a statistically significant effect on the average head weight (+55.45 g plant-1 with 15-cm beds) with significant increases of field yields (up to +30.6%) and net incomes (up to +29.7%) on the trials with flat seed-beds. The experiment showed that the production of chicory can take an economical advantage from the use of raised seed-beds and, therefore, this system is preferable to the traditional cultivation practice

Precoat filtration with body-feed and variable pressure. Part II: Experimental tests and optimization of filtration cycles

The classical theory of the precoat filtration with body-feed suggests the Carman equation obtained by integration of the Darcy ODE with constant pressure. Hereinafter the equation obtained in Part I by mean a mathematical modelling of the precoat filtration with body-feed in more realistic conditions of variable pressure was re-called and an experimental validation was done. A pilot filter equipped with a small centrifugal pump was used. The experimental results of the curve of filtrate volume vs. filtration time were compared both with the new equation curve and the Carman equation curve. In the specific conditions of laboratory testing, the estimation error in the filtration time with the new equation is -3.7%, while the estimation error with the classical Carman equation is -21.6%. But with higher permeability conditions of the filtration layer the error with Carman equation can greatly increase, as it was contemplate in Part I. The precoat filtration with body-feed must be followed by the filter cleaning. The research of an optimization of the filtration-cleaning cycle using the classic theory of filtration, and therefore the Carman equation, leads to the well known condition to have equal both filtration time and cleaning time. With the proposal of the new equation, in this work a new modelling of the cycle optimization was elaborated. It provided a ratio between filtration time and cleaning time always greater than 1 with values also up to 16 for the higher permeability of the filtering layer . Therefore, the use of the previous optimization with a rate equal 1 is unacceptable with higher permeability, leading to a substantial halving of the filter productivity

A Tool for the Evaluation of Irrigation Water Quality in the Arid and Semi-Arid Regions

In the Mediterranean arid and semi-arid regions, large amounts of low quality waters could be used for crop irrigation, but the adoption of articulated classifications with too rigid quality limits can often reduce the recoverable quantities of water and make the monitoring of water quality too much expensive. Therefore, an evaluation of irrigation water quality based on only a few crucial parameters, which consider the crop species to be irrigated and the type of irrigation system and management adopted, can be an easy and flexible method for maximizing the reuse of wastewater and low-quality water for agricultural purposes. In this view, an irrigation water quality tool (IWQT) was developed to support farmers of arid and semi-arid regions on evaluating the use of low quality water for crop irrigation. The most significant and cheapest parameters of irrigation water quality were identified and clustered in three quality classes according to their effects on crop yield and soil fertility (agronomic quality indicators), human health (hygiene and health quality indicators), and irrigation systems (management quality indicators). According to IWQT parameters, a tool reporting a series of recommendations, including water treatment types, was implemented to guide farmers on the use of low quality irrigation water

Precoat filtration with body-feed and variable pressure. Part I: Mathematical modelling

The precoat filtration with body-feed is an unit operation of agricultural and food engineering. Mostly it is implemented by using centrifugal pump, which pump curve has a partial horizontal trend. Classically, in filtration theory, this prerogative of the centrifugal pumps leads to the simplifying assumption that filtration occurs with constant pressure. Because of this, it is easy to integrate the Darcy\u2019s differential equation [1, 2 and 3] for the precoat filtration with body-feed, obtaining the well known Carman equation [4]. This is the equation which relates the filtration time with the filtrate volume, the operating pressure, the filter area, and the solid-liquid suspension characteristics. The Carman equation is the start point for the subsequent optimization of the filtration cycles, e.g. by establishing the relationship between the filtration time and the filter cleaning time [5]. A better optimization of the precoat filtration with body-feed could be obtain, with some economic benefits, if an integration of the Darcy ODE was developed starting from actual trend of the pressure produced by the centrifugal pump, that is if a variable pressure was considered, as expected from the pump curve. In this sense a proposal was done by Tiller and Crump [6] many years ago in accordance with a graphic method of integration of the Darcy ODE. However the graphic procedure is tedious since it is iterative and not computerizable. For this reason the aim of this work was to find an analytical solution to the Darcy ODE for the filtration with variable pressure in order to obtain a quick and easy-to-use equation for the subsequent optimization calculations of filtration cycles, even if more complex of the Carman equation

Assessing Stormwater Nutrient and Heavy Metal Plant Uptake in an Experimental Bioretention Pond

With the purpose to study a solution based on Sustainable Urban Drainage Systems (SUDS) to reduce and treat stormwater runoff in urban areas, a bioretention pond (BP) was realized in the Agripolis campus of the University of Padova, Italy. The BP collected overflow water volumes of the rainwater drainage system of a 2270 m2 drainage area consisting almost entirely of impervious surfaces. Sixty-six Tech-IA\uae floating elements, supporting four plants each, were laid on the water surface. Eleven species of herbaceous perennial helophyte plants, with ornamental features, were used and tested. The early growth results of the BP functioning showed that nearly 50% of the total inflow water volume was stored or evapotranspirated, reducing the peak discharge on the urban drainage system. Among plants, Alisma parviflora, Caltha palustris, Iris \u2018Black Gamecock\u2019, Lysimachia punctata \u2018Alexander\u2019, Oenanthe javanica \u2018Flamingo\u2019, Mentha aquatica, Phalaris arundinacea \u2018Picta\u2019, and Typha laxmannii had the best survival and growth performances. A. parviflora and M. aquatica appeared interesting also for pollutant reduction in runoff water

Efficiency & sustainability model to design and manage two-stage logistic networks

The distribution and storage efficiency together with the environmental sustainability are mandatory targets to consider when designing and managing modern supply chain (SC) networks. The current literature continuously looks for quantitative multi-perspective strategies and models, including and best balancing such issues that often diverge. This paper presents and applies a bi-objective optimization model to best design and manage two-stage logistic networks looking for the best trade-off between the SC stock level and the building and distribution environmental impact. The existence of good balance confirms the possibility to reduce the average SC stock level without a relevant increase of the emissions due to frequent replenishments

Radicchio cultivation under different sprinkler irrigation systems

Gun sprinklers were commonly used in Italy to irrigate Radicchio. Although this high-pressure irrigation system allows large areas to be irrigated in a short time, it has some major disadvantages. Disadvantages include the impact of the drops on the soil and crop can be very strong, the high volume of water used tends to increase water use and runoff and water distribution uniformity is low. A 3-year experiment was conducted in North-East Italy in order to evaluate the possibility of using a mini-sprinkler irrigation system with low-volume application rates. The use of mini-sprinkler resulted in a higher distribution uniformity, higher Christiansen uniformity coefficient and a higher water use efficiency. Energy cost was also lower when the mini-sprinkler system was used for irrigation as compared to the irrigation gun system. Radicchio head weight and marketable yield were higher when plants were irrigated with the mini-sprinkler as compared to those irrigated with the irrigation gun. Therefore, the use of mini-sprinklers resulted in not only a reduction in water use and energy cost but also an increase in radicchio production

Design, control and management of renewable energy plants and technologies

Nowadays, and even more in the next decades, the availability and easy-access to energy sources represent a crucial asset for the world development and the progress of people and nations. At the same time, the depletion of natural resources, together with the increase of the anthropic activity impact on the Earth ecosystem and climate, force communities and institutions, at all levels, to discuss and actuate different approaches to achieve the social and economic growth, based on the so-called sustainable development pattern. In such a scenario, renewable energy sources, i.e. solar, wind, hydro, biomass, geothermal, etc., certainly play a key role to join progress and attention to the environmental issues. The present Ph.D. dissertation focuses on such topics investigating strategies, methods and innovative approaches for the effective design, control and management of renewable energy plants and technologies. Specifically, the energy scenario is investigated from a global point of view proposing studies and optimization models highlighting the relevance and the potential impact of the major energy sources, both renewable and conventional. Such sources represent the elements of a big puzzle, i.e. the energy mix, in which their economic and environmental strengths should be emphasized minimizing the associated negative impacts and weaknesses. Among renewable sources, solar energy is of primary importance for availability, diffusion and potential impact. The present Ph.D. dissertation particularly investigates such a source presenting models, methods and prototypes to increase its relevance in the energy mix. The fundamentals of solar energy, together with innovative approaches to estimate the solar radiation components, are provided. Furthermore, the pioneering concentrating solar sector is deeply focused presenting the design, development and preliminary field-test of a bi-axial Fresnel solar photovoltaic/thermal (PV/T) concentrating prototype. Possible solar tracking strategies and control algorithms are, then, investigated describing a customized semi-automatic motion control platform, developed in LabViewTM programming environment. Finally, the last section, proposes an effective approach for the design of a solar simulator, the most frequently adopted device in solar optic laboratory tests. In conclusion, the present Ph.D. dissertation describes effective strategies for the renewable energy spread, considering their performances and their potential impact to achieve the ambitious challenge of a sustainable living planet

Solovey and Cravens: Cold War Social Science

Book Review of: Mark Solovey and Hamilton Cravens (eds.), Cold War Social Science: Knowledge Production, Liberal Democracy, and Human NatureNew York: Palgrave Macmillan 2014First paperback ed., xvii + 270 pp.ISBN 978-1-137-38835-3Price: € 3