Search results for "Nutrients"

ESTIMATES OF C/N STOICHIOMETRY AND N RETENTION OF FOUR MEDITERRANEAN WETLAND SPECIES SUBJECTED TO WATER INPUTS FROM AN EFFLUENT OF A WASTEWATER TREAT…

2017

Effects of fish-farm biodeposition on periphyton assemblages on artificial substrates in the southern Tyrrhenian Sea (Gulf of Castellammare, Sicily)

2007

An algal assemblage growing on artificial substrata of fish-farm cages was investigated. Specifically, algal response to the effects of fish-farm facilities was studied, in order to identify a possible future descriptor of biodeposition impact. Some sites were positioned upstream of the farms (at least 750 m; ‘controls’) and other sites were positioned downstream of the farms (‘impacts’). All sites were situated in the Tyrrhenian Sea. Control and impact sites differed significantly with regard to the dissolved nutrient profile. The fouling community (samples were scraped from buoys) displayed a reduction gradient in diversity which increased with the effect of fish farms. A total of 51 taxa…

Ecological impacts of global warming and water abstraction on lakes and reservoirs due to changes in water level and related changes in salinity

2015

According to the Intergovernmental Panel on Climate Change report released in September 2014, unprecedented changes in temperature and precipitation patterns have been recorded globally in recent decades and further change is predicted to occur in the near future, mainly as the result of human activity. In particular, projections show that the Mediterranean climate zone will be markedly affected with significant implications for lake water levels and salinity. This may be exacerbated by increased demands for irrigation water. Based on long-term data from seven lakes and reservoirs covering a geographical gradient of 52 of latitudes and a literature review, we discuss how changes in water le…

Laghi Artificiali dell'Italia meridionale e delle isole maggiori

2014

In questo articolo gli autori analizzano i principali fattori ecologici che determinano il funzionamento dei laghi artificiali localizzati nel meridione d’Italia e nelle isole maggiori. In particolare, viene illustrato come il ciclo idrologico annuale di questi ecosistemi sia fortemente influenzato dalle attività umane connesse all’uso dell’acqua invasata. Tali attività spesso interferiscono negativamente con la dinamica dei fattori fisici (stratificazione/circolazione), chimici (concentrazioni di nutrienti e ossigeno) e biologici (successione stagionale del fitoplancton) che governano il funzionamento di questi ecosistemi. Comprendere come il cambiamento climatico in atto influenzi il cicl…

Greenhouse Gas Emissions from Membrane Bioreactors

2017

Nowadays, it is widely accepted that wastewater treatment plants (WWTPs) are significant sources of greenhouse gas (GHG) emission, contributing to the anthropogenic sources. Among the GHG emitted from WWTPs, nitrous oxide (N2O) has been identified of having the major interest/concern, since its high global warming potential (GWP), is 298 times higher than that of CO2 and also to its capability to react with stratospheric ozone causing the layer depletion. Up to now, most of the experimental investigations have been carried out on conventional activated sludge (CAS) processes. The knowledge of N2O emission from advanced technologies such membrane bioreactors (MBRs) is still very limited. The…

Wastewater treatment sludge composting

2023

In recent years, the amount of sewage sludge generated by wastewater treatment plants (WWTPs) has increased due to worldwide population growth and to efficiency of biological treatment processes [1,2]. Sludge is an important source of secondary pollution to aquatic environments and a potential risk to human health; moreover, it represents one of the most important cost items in the functioning of water treatment plants [3–5]. About 60% of the operating costs of secondary wastewater treatment plants in Europe can be associated with the treatment and disposal of products [6]. For this reason, proper sludge management becomes increasingly important, at both national and international level, an…

Similar prediction of the decreased total mortality, diabetes incidence or cardiovascular events using a relative- and an absolute-component Mediterr…

2013

Abstract Background and Aim: Accumulated evidence supports the effectiveness of Mediterranean-type diets (MeDiet) in reducing mortality and preventing several chronic diseases. Widely used scores to assess adherence to MeDiet are based on specific sample characteristics; alternatively, they might be built according to absolute/normative cut-off points for the consumption of specific food groups (pre-defined servings/day or/week). The aim of this study was to compare sample-specific MeDiet adherence scores (MDS) versus absolutenormative scores (Mediterranean Diet Adherence Screener e MEDAS) on their association with macronutrient intake, total mortality and incidence of chronic diseases. Des…

Sampling procedure in a willow plantation for chemical elements important for biomass combustion quality

2015

Willow (Salix spp.) is expected to contribute significantly to the woody bioenergy system in the future, so more information on how to sample the quality of the willow biomass is needed. The objectives of this study were to investigate the spatial variation of elements within shoots of a willow clone ‘Tordis’, and to reveal the relationship between sampling position, shoot diameters, and distribution of elements. Five Tordis willow shoots were cut into 10–50 cm sections from base to top. The ash content and concentration of twelve elements (Al, Ca, Cd, Cu, Fe, K, Mg, Mn, Na, P, Si, and Zn) in each section were determined. The results showed large spatial variation in the distribution of mos…

Effect of macro and micro nutrients addition during anaerobic mono-digestion of grass silage in leach-bed reactors

2019

The effect of macro- (NH4Cl) (set I) and micro-nutrients (Fe, Ni, Co and Mo) (set II) addition on chemical oxygen demand (COD) solubilisation during anaerobic mono-digestion of grass silage was investigated in two sets of leach bed reactor experiments at 35°C. Results showed that addition of NH4Cl and micro-nutrients improved COD solubilisation by 18% (0.56 g SCOD g−1 volatile solids) and 7% (0.45 g SCOD g−1 VS), respectively than control. About 20–50% of the added micro-nutrients were bioavailable in the produced leachates, while the rest (50–80%) were adsorbed onto the grass silage. Results of biological methane potential assays showed that, specific methane yields of grass silage were im…

Serine- and Threonine/Valine-Dependent Activation of PDK and Tor Orthologs Converge on Sch9 to Promote Aging

2014

Dietary restriction extends longevity in organisms ranging from bacteria to mice and protects primates from a variety of diseases, but the contribution of each dietary component to aging is poorly understood. Here we demonstrate that glucose and specific amino acids promote stress sensitization and aging through the differential activation of the Ras/cAMP/PKA, PKH1/2 and Tor/S6K pathways. Whereas glucose sensitized cells through a Ras-dependent mechanism, threonine and valine promoted cellular sensitization and aging primarily by activating the Tor/S6K pathway and serine promoted sensitization via PDK1 orthologs Pkh1/2. Serine, threonine and valine activated a signaling network in which Sch…