Search results for " quality."

The role of soils in regulation and provision of blue and green water

2021

The United Nations Sustainable Development Goal 6 aims for clean water and sanitation for all by 2030, through eight subgoals dealing with four themes: (i) water quantity and availability, (ii) water quality, (iii) finding sustainable solutions and (iv) policy and governance. In this opinion paper, we assess how soils and associated land and water management can help achieve this goal, considering soils at two scales: local soil health and healthy landscapes. The merging of these two viewpoints shows the interlinked importance of the two scales. Soil health reflects the capacity of a soil to provide ecosystem services at a specific location, taking into account local climate and soil condit…

Remote sensing of cyanobacterial blooms in a hypertrophic lagoon (Albufera of València, Eastern Iberian Peninsula) using multitemporal Sentinel-2 ima…

2018

Eutrophy in Albufera of Valencia (Eastern Iberian Peninsula) is a quite old problem since after the intense eutrophication processes throughout the 1960s. The system shifted to a turbid stable state consolidated by the virtual disappearance of macrophytes by the early 1970s. The lagoon has been studied extensively since the 1980s, but efforts to revert the system to a clear state have not yielded the expected results because cultural eutrophication due to the growth of population in its area of influence and the effects of climate change, decreasing rainfall and increasing evaporation. This has driven to an increase in water retention times in the lagoon in recent years, resulting in a phyt…

Interpreting and modelling field data for wastewater dispersion into sea through dimensional analysis

2008

Optinių baliklių skalbimo priemonėse liuminescencijos tyrimas siekiant sukurti optinius aplinkosauginius vandens kokybės kontrolės jutiklius

2006

Water quality and anthropogenic loads in many, but not all, cases are related. Some water quality monitoring programs analyse samples for the presence of Escherichia coli. These bacteria can come from humans and animals. Human-attributable effluent contains optical brighteners (OBs) from detergents. A convenient and affordable optical quantitative method giving a linear luminescence outcome over several orders of detergent concentrations in the water solution is demonstrated. The proposed method uses the common presence of OBs in detergents. Detergent concentration in water can be used as a surrogate indicator of resultant anthropogenic loads in water bodies. The proposed optical method wit…

Role of modeling uncertainty in the estimation of climate and socioeconomic impact on river water quality. J. of Water Resources Planning and Managem…

2012

Climate is one of the most important factors leading to changes in the hydrologic and environmental characteristics of river basins. When considering water quality, the natural factors should be weighed against anthropogenic factors (such as urbanization, increased population, and higher water demand) that may increase or decrease the effect of climatic modifications. Any prediction of future climatic and anthropogenic scenarios is affected by uncertainty and the modelling tools that are used for evaluating their impact on receiving water bodies. The present paper is aimed at investigating the complexity of such analyses and the uncertainty related to future impact predictions based on limi…

Mediterranean Climate and Eutrophication of Reservoirs: Limnological Skills to Improve Management

2011

Sicily is the largest Mediterranean island and one of the most densely populated areas in the region. To counteract the periodic oscillation in water availability and fulfill drinking and agriculture needs, about 30 dam-reservoirs, impounding in total 750 106 m3, were built in the last 60 years. However, the inherent features of the Mediterranean climate and the total lack of awareness from local authorities have contributed to a progressive increase in the trophic state of these human-made lakes. In particular, the water is stored during the winter rainy season and then it is intensively used in the dry summer. These operational procedures, in particular the time separation between filling…

An optical classification tool for global lake waters

2017

Shallow and deep lakes receive and recycle organic and inorganic substances from within the confines of these lakes, their watershed and beyond. Hence, a large range in absorption and scattering and extreme differences in optical variability can be found between and within global lakes. This poses a challenge for atmospheric correction and bio-optical algorithms applied to optical remote sensing for water quality monitoring applications. To optimize these applications for the wide variety of lake optical conditions, we adapted a spectral classification scheme based on the concept of optical water types. The optical water types were defined through a cluster analysis of in situ hyperspectral…

In vitro optical performance of a new aberration-free intraocular lens

2014

To assess the optical performance of the new EnVista intraocular lens (IOL). Four aspheric IOLs were evaluated; the new EnVista is one amoung them. This IOL, similarly to the Z-Flex HB and the Bi-Flex 1.8 667AB ones, has a neutral aspheric design, whereas the fourth IOL under test (AcrySof IQ IOL SN60WF) presents a negative spherical aberration (SA). The IOL’s aberration patterns were measured in vitro, by setting them up on an optical bench. From these aberration-pattern data, the modulation transfer function (MTF), the average modulation values, and the points spread function (PSF) were calculated. Furthermore, in order to assess the potential optical quality that these IOLs would yield o…

Image transmission through dynamic scattering media by single-pixel photodetection

2014

Smart control of light propagation through highly scattering media is a much desired goal with major technological implications. Since interaction of light with highly scattering media results in partial or complete depletion of ballistic photons, it is in principle impossible to transmit images through distances longer than the extinction length. Nevertheless, different methods for image transmission, focusing, and imaging through scattering media by means of wavefront control have been published over the past few years. In this paper we show that single-pixel optical systems, based on compressive detection, can also overcome the fundamental limitation imposed by multiple scattering to suc…

Experimental validation of a customized phase mask designed to enable efficient computational optical sectioning microscopy through wavefront encodin…

2017

In this paper, wavefront-encoded (WFE) computational optical sectioning microscopy (COSM) using a fabricated square cubic (SQUBIC) phase mask, designed to render the system less sensitive to depth-induced aberration, is investigated. The WFE-COSM system is characterized by a point spread function (PSF) that does not vary as rapidly with imaging depth compared to the conventional system. Thus, in WFE-COSM, image restoration from large volumes can be achieved using computationally efficient space-invariant (SI) algorithms, thereby avoiding the use of depth-variant algorithms. The fabricated SQUBIC phase mask was first evaluated and found to have a 75% fidelity compared to the theoretical desi…