Search results for "man-made"

Studies on Italian reservoirs

1992

The main morphometric and water quality characteristics of the 221 Italian reservoirs covering an area of at least 0.2 km2 is given. Most of the reservoirs are used for drinking water purposes, especially on the islands of Sicily and Sardinia, where the more important cases of eutrophication have been found. These situations are examined in greater detail, with regard to algal population dynamics, the phosphorus budget and the comparison between theoretical and experimental nutrients loads. -from Authors

Phytoplankton dynamics in two reservoirs with different trophic state (Lake Rosamarina and Lake Arancio, Sicily, Italy)

1998

Two man-made Sicilian lakes of differing trophic status were sampled weekly for a year, in order to compare their phytoplankton dynamics and to identify their driving factors. The water bodies store comparable volumes but the eutrophic Lake Arancio may be considered to be a shallow lake whereas the mesotrophic Lake Rosamarina is deep. The dynamics of their principal physical, chemical and biological features were analysed using, among others, Canonical Community Ordination. The results obtained suggest that increased nutrient availability causes an increase of phytoplankton biomass but no community change nor any alteration to the typical assemblages supported. The major influence in the mo…

Distribution patterns of phytoplankton functional groups in connected/isolated reservoirs in an urban drinking water system

2015

Eighteen reservoirs belonging to an urban drinking water system (Zhuhai city, South China) were investigated in the dry and flood seasons of 2013 to evaluate how hydrological connectivity may affect the specie richness and functional composition of phytoplankton. Eleven among the studied water bodies are connected through pipelines and seven are isolated. Twenty one phytoplankton functional groups were identified in the studied reservoirs. Cluster analysis showed that phytoplankton similarity is higher among connected reservoirs than among isolated ones. The average α-diversity is high in the connected reservoirs, but the average β-diversity is much higher in the isolated reservoirs. The hi…

Phytoplankton assemblages in reservoirs: Is it chemical or physical constraints which regulate their structure?

1998

Data on phytoplankton assemblages and the correspondent environmental variables, collected in a limnological investigation carried out on 21 Sicilian reservoirs between 1987 and 1988, were ordered to clarify which physical (light availability, mixing depth), chemical (nutrient availability) and biological (grazing pressure) parameters modulate the structure of the assemblages. In particular, data sets were analyzed using CANOCO 3.1. The results of the analysis have shown that physical factors are more important in selecting species for those environments subject to pronounced water-level fluctuations. The reasons of such strong influence may be understood in the secondary modifications that…

EUNIS Habitat Classification: Expert system, characteristic species combinations and distribution maps of European habitats

2020

Aim The EUNIS Habitat Classification is a widely used reference framework for European habitat types (habitats), but it lacks formal definitions of individual habitats that would enable their unequivocal identification. Our goal was to develop a tool for assigning vegetation-plot records to the habitats of the EUNIS system, use it to classify a European vegetation-plot database, and compile statistically-derived characteristic species combinations and distribution maps for these habitats. Location Europe. Methods We developed the classification expert system EUNIS-ESy, which contains definitions of individual EUNIS habitats based on their species composition and geographic location. Each ha…

Importance of water-level fluctuation on population dynamics of cladocerans in a hypertrophic reservoir (Lake Arancio, south-west Sicily, Italy)

1997

During a period of three years (1990-1991 and 1993), we studied the population dynamics of planktonic cladocerans in a hypertrophic reservoir. Weekly sampling revealed that the five most common species followed a trend which reflects the peculiar hydrological characteristics of the reservoir and their key position in the pelagic food web. In particular, 1991 was characterized by a strong water inflow which probably interfered with the reproductive activities of the dominant fish population (Rutilus rubilio) and reduced the concentration of inedible planktonic algae allowing the development of small Chlorococcales. This event was associated with higher population densities of Daphnia hyalina…

Urban Services to Ecosystems: An Introduction

2021

Green infrastructure is a structural system of naturally developed human societies, capable of preserving and ensuring as much space as possible to the local biodiversity. For this reason, green infrastructure shall be planned and designed so that the urban built environment is in harmony with the surrounding biotic communities. The challenge is to sustain nature-based solutions in order to improve citizens’ awareness towards natural and semi-natural ecosystems while providing our society with a more liveable, healthier, safer and fairer environment. This book puts an emphasis on the services the city can offer to nature, thanks to a multidisciplinary approach involving scientists and pract…

The vegetation of a historic road system in the suburban area of Monte Pellegrino (Palermo, Sicily)

2020

Knowledge of the processes by which plants colonize old structures is a key element for nature-based design both in urban and suburban contexts. This paper analyses the natural vegetation on walls and in other microhabitats of the roadway structures of Monte Pellegrino (606 m a.s.l.) near Palermo (Sicily), built in the first half of the 1900s. The historical road has particular construction and architectural features, and its characteristics have been maintained to this day. The route, approximately 16 kilometers long, is well integrated within a site of high naturalistic value which has been designated as a Special Area of Conservation (ITA020014) of the Natura 2000 network, and it is also…

Climate change and enhancement of water-level fluctuations in Mediterranean reservoirs: a sad fate for water quality?

2010

Urban Services to Ecosystems - Green Infrastructure Benefits from the Landscape to the Urban Scale

2021

The aim of this book is to bring together multidisciplinary research in the field of green infrastructure design, construction and ecology. The main core of the volume is constituted by contributions dealing with green infrastructure, vegetation science, nature-based solutions and sustainable urban development. The green infrastructure and its ecosystem services, indeed, are gaining space in both political agendas and academic research. However, the attention is focused on the services that nature is giving for free to and for human health and survival. What if we start to see things from another perspective? Our actions shall converge for instance to turn man-made environment like cities f…