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International audience; Uncertainty is an important factor in ecological assessment, and has important implications for the ecological classification and management of lakes. However, our knowledge of the effects of uncertainty in the assessment of different ecological indicators is limited. Here, we used data from a standardized campaign of aquatic plant surveys, in 28 lakes from 10 European countries, to assess variation in macrophyte metrics across a set of nested spatial scales: countries, lakes, sampling stations, replicate transects, and replicate samples at two depth-zones. Metrics investigated in each transect included taxa richness, maximum depth of colonisation and two indicators of trophic status: Ellenberg’s N and a metric based on phosphorus trophic status. Metrics were found to have a slightly stronger relationship to pressures when they were calculated on abundance data compared to presence/absence data. Eutrophication metrics based on helophytes were found not to be useful in assessing the effects of nutrient pressure. These metrics were also found to vary with the depth of sampling, with shallower taxa representing higher trophic status. This study demonstrates the complex spatial variability in macrophyte communities, the effect of this variability on the metrics, and the implications to water managers, especially in relation to survey design.

The natural variability of the biotic components, in particular of those showing seasonal cycles, often leads to significant changes of biomass as well as specific composition. This means that the choice of sampling frequency and distribution during the year may be crucial when assessing the ecological quality of a waterbody, starting from the structure of biotic communities. Among the four biological quality elements used to classify the lakes, three of them (phytoplankton, macrophytes and macroinvertebrates) show a marked seasonality and/or a certain degree of spatial variability. This document has the aim to evaluate how the metrics used are sensitive to the natural variability, especially respect to their response to the pressure gradients. The analysis was carried out on data collected during the project and is limited to phytoplankton and macrophytes, because the examination of autumn samples of macroinvertebrates, is still in progress. Regarding phytoplankton, three metrics defined by Italian national legislation (composition indices, chlorophyll and biovolume) were analyzed, comparing the variability due to anthropogenic origin (expressed by the gradient of total phosphorus) with the natural one (seasonal variations on different time scales) and estimating the uncertainty in the classification using different sampling frequencies. In the case of macrophytes, monitoring methods and classification were analyzed respect to their accuracy in assessing if the variability between sites, explained by a different anthropogenic pressure, is actually greater than the variance within the individual lake. In addition, we want to determine if the sampling effort, as established by the monitoring protocols, is adequate to the needs of the classification. Our analysis showed that the variability of phytoplankton metrics reflects the trophic gradient and is more significant than that explained by seasonal fluctuations, demonstrating the robustness of the indicators used. Moreover, the phytoplankton assemblages reveal a high stability in interannual patterns of succession. Conversely, the general formulation of the macrophytic index may need to be redefined to better understand the differences in ecological quality between lakes. Furthermore, as concerns macrophytes, a significant reduction of the sampling effort does not seem to be possible without compromising the quality of classification, while, as regards phytoplankton, it would be acceptable to reduce the number of annual samples from 6 to 4 without compromising the result of the classification, while observing the seasonality, because our analysis suggests that phytoplankton samples concentrated in a single season lead to increased uncertainty in the classification.

A relational database was set up to host the hydromorphological data produced within the InHabit project. To avoid proprietary software or data format, we build the database using PostgreSQL, an Open Source Relational Database Management system. The data base contains information on the habitat surveys. The database contains all data collected within the InHabit project up to October 2011. At the moment, Lake Habitat survey information are available for 13 lakes and or reservoirs, totaling 170 habitat plots an 170 inter-plot shore descriptions.

This report presents an analysis of the relationships between environmental variables and organisms belonging to the four biotic communities used to define the lake's ecological quality, according to provisions of the Italian legislation (D.Lgs. 260, November 2010) and the European Water Framework 2000/6. The data analyzed were collected during the sampling surveys carried out within InHabit Project in 13 water bodies, 7 in Piedmont and 6 in Sardinia respectively. In particular, the aim of the study was to evaluate the possible effects of nitrogen on biotic communities. Phytoplankton community shown the clearer responses: according to the result of multivariate analysis, total nitrogen and ammonium nitrogen are among the most significant factors explaining the relationships among phytoplankton orders, species and environmental variables. In particular, cyanobacteria increased considerably with increasing availability of ammonium nitrogen. Conversely, high concentrations of this compound suppress the development of diatoms. Other algal groups show a nonlinear response with respect to nitrogen, with a possible limitation under low levels of nitrogen and an inhibition at higher levels. A comparative analysis, carried out to evaluate the response to the gradient of total phosphorus, shows that this nutrient is not as selective as nitrogen in controlling the structure of the algal assemblage in different environmental conditions. Other biotic communities did not show a clear relationship with nitrogen, but they rather responded to the trophic gradient as a whole: responses by macroinvertebrates seem, especially in the analysis of functional groups, complex and difficult to discriminate, highlighting a possible shifting of the food web towards the presence of large carnivores at high trophic status. Regarding the fish, the results show that nitrogen alone does not seem to be an important controlling factor for the fish communities. However together with the phosphorus, is one of the main elements controlling both biomass and size of the fish fauna, as well as the presence of tolerant, omnivorous or benthofagous species. In conclusion, the results of our analysis highlight the need for a greater emphasis on nitrogen inputs, which, especially in cases of nitrogen carried by atmospheric deposition, may even affect lake ecosystems relatively distant from direct impacts of human activities, thus altering the structure of biotic communities.

During the last two decades Lago Maggiore, the second largest Italian lake, located in the subalpine lake district, moved from meso-eutrophy during the mid- 1970s to an oligotrophic condition as a consequence of change in the nutrient load (MANCA et al. 1992, DE BERNARDI et al. 1996). Following the decrease of inlake TP concentration, notable changes in the plankton assemblages occurred (MANCA & RUGGIU 1998, RUGGIU et al. 1998) after a period of resilience of the plankton communities against falling phosphorus. Different trophic states affect the capacity of a system and the biomass a lake can support (REYNOLDS 1997). This study evaluates algal levels, measured as chlorophyll a, in Lago Maggiore during its recent trophic evolution. We calculated potential algal carrying capacity based on phosphorus and solar radiation, representing nutrient and energy limitation, respectively. We analysed the relationship between these two resources during the lake's trophic evolution by dividing the data series into three periods corresponding to the response of the lake to decreasing phosphorus load.

Charophytes (stoneworts and bassweeds) are a typical macrophytic component of inland water ecosystems. Well-developed submerged meadows of charophytes are expression of clear water and rather low phytoplankton concentrations. Consequently, among aquatic macroscopic primary producers, charophytes are one of the most threatened groups being very sensitive to phosphorous availability, turbidity and water level perturbations. Accordingly, charophytes have been suffering a massive diversity loss worldwide over the last century, mainly because of human-induced pressures. During summer 2011, detailed field surveys were carried out with the main purpose of filling knowledge gaps concerning aquatic flora and vegetation of the lake Garda – the largest lake in Italy and one of the deepest in Europe. Along randomly selected transects, floristic data were collected following standard procedures, as imposed by the Water Framework Directive. Overall, 12 different species of charophytes were recorded, which accounts for 36% of total Italian charophytes and 19% of European species. The most diffuse species were Chara globularis and C. intermedia; whereas, the most interesting taxa were Chara polyacantha and Nitella hyalina, two species with narrow distribution in Italy. Overall in the lake Garda, dense stands of charophytes covered almost homogeneously the littoral sectors at a water depth between 3 and 12 m. The deepest species was C. globularis, which reached a maximum depth of colonisation of about 17.5 m. Charophytes represent a major element among the primary producers in the lake Garda. The high local charophyte diversity and the rather wide most colonised areas (~1000-1200 ha) confirm that the lake Garda is an important reserve for many rare and threatened charophytes. For the first time, these results highlight the key role of the lake Garda for charophyte diversity at a national and European level.

We present a novel approach to the management of Spatial Data Infrastrutures that leverages semantics-aware context information to model the distinct aspects involved in the management of spatial data. RDF-based schemata are employed for encoding information on the user community, the terminologies in use in a specific research domain, gazetteer information representing the physical landscape hosting data and, last but not least, spatial resource metadata. The data structures are then interconnected to enable seamless exploitation for metadata creation and resource discovery, which we demonstrate through a worked-out example of SPARQL query on RDF graph data. The methodology is being applied by by the National Research Council (CNR) of Italy to support creation of a distributed infrastructure for marine data in the context of the RITMARE Flagship Project.

Managing real time data collected by a network of heterogeneous sensors from marine sites needs to face challenges such heterogeneity, quality check, harmonization, description of sensors, etc. This is the purpose of the proof-of-concept described in this paper; it tests the suitability of OGC Sensor Web Enablement services, exploiting in particular the Sensor Observation Service (SOS) and the associated SensorML and O&M standards. Two Italian marine observatories have been included in the proof, both belonging to CNR ISMAR; they are the oceanographic Platform "Acqua Alta" and a weather station in Venice (Italy). They measure multiple real time parameters and distribute them by OGC SOS. The multilayer architecture and the service approach adopted enable decoupling of components; in particular, the proof shows that each Institution hosting a sensor station is allowed to store observations and deliver them to multiple independent clients, in a standard, interoperable way, well recognized and accepted at European and global scale. The proof has been implemented and tested in three scenarios to retrieve and display descriptions of stations, sensors and measurements available; to retrieve and display observations of one parameter selected from multiple sensors; to retrieve observations of all parameters collected from sensors of a specific station.

This study reports the first preliminary results of the DYRESM-CAEDYM model application to a mid size sub-alpine lake (Lake Pusiano North Italy). The in-lake modelling is a part of a more general project called Pusiano Integrated Lake/Catchment project (PILE) whose final goal is to understand the hydrological and trophic relationship between lake and catchment, supporting the restoration plan of the lake through field data analysis and numerical models. DYRESM is a 1D-3D hydrodynamics model for predicting the vertical profile of temperature, salinity and density. CAEDYM is multi-component ecological model, used here as a phytoplankton-zooplankton processes based model, which includes algorithms to simulate the nutrient cycles within the water column as well as the air-water gas exchanges and the water-sediments fluxes. The first results of the hydrodynamics simulations underline the capability of the model to accurately simulate the surface temperature seasonal trend and the thermal gradient whereas, during summer stratification, the model underestimates the bottom temperature of around 2 degrees C. The ecological model describes the epilimnetic reactive phosphorus (PO4) depletion (due to the phytoplankton uptake) and the increase in PO4 concentrations in the deepest layers of the lake (due to the mineralization processes and the sediments release). In terms of phytoplankton dynamics the model accounts for the Planktothrix rubescens dominance during the whole season, whereas it seems to underestimate the peak in primary production related to both the simulated algal groups (P. rubescens and the rest of the other species aggregated in a single class). The future aims of the project are to complete the model parameterization and to connect the in-lake and the catchment modelling in order to gain an integrated view of the lake-catchment ecosystem as well as to develop a three dimensional model of the lake.

International audience; Within the INSPIRE framework, data pertaining to observations or measurements of environmental phenomena, often collected through sensors, are to be provided in addition to spatial features; these are usually consolidated in monitoring networks specifically designed to address various environmental issues and related policies. The Environmental Monitoring Facilities (EF) data model describes environmental monitoring facilities as spatial objects in the context of INSPIRE, it includes observations and measurements (O&M) linked to the environmental monitoring facilities, together with relevant metadata on the measurement methodology and process. The OGC Sensor Observation Service (SOS) has been identified as well suited for the provision of O&M encoded data; last December the technical guidance document for the implementation of SOS as an INSPIRE download service were finalized. In addition, the guidelines for the usage of O&M within INSPIRE have been updated to version 3. Both of these documents will be presented, including necessary extensions to the OGC service specifications. Almost one year has passed since the adoption of the technical guidance for SOS and O&M in INSPIRE. Thus, it is time to investigate a broad spectrum of interdependent topics, including (i) feedback from implementers, (ii) challenges related to the currently existing technical guidance documents and the maturity of available technology, and (iii) an outlook for the future of observation data in INSPIRE considering the rapidly changing technological scenery. Within this context, the main focus of this workshop will be on the integration of SOS services with established INSPIRE download services such as WFS; the utilization of Web Processing Services (WPS) or interactive environments (e.g. Virtual Research Environments - VRE, interactive computational environments, etc.) for enrichment of O&M data shall also be taken into account. O&M based data architectures and information flows will be discussed, as well as referencing between service types, illustrating how INSPIRE data stemming from SOS and WFS services can be integrated to complex applications for a wide range of environmental domains. Server and client implementations from various environmental domains will be presented and discussed, including a perspective towards open science solutions. Based on feedback gained during the workshop we will also work on prioritizing next steps on various pending issues, ranging from (i) known deficits within the underlying OGC standards, (ii) development and uptake of new standards such as JSON encoding, and (iii) the new OGC SensorThings API standard.

Introduction of alien species is one of the major threats to aquatic biota and knowledge of the major correlates of their occurrence is pivotal in planning reliable conservation strategies. To understand whether specific freshwater habitats are more likely to be invaded than others, a dataset on the occurrence of 1604 species in 54 taxonomic groups from 181 sites across the Italian peninsula was gathered. The EUNIS habitat classification was used, selecting for the study's seven habitat types at the second EUNIS level, including lentic (EUNIS C1; 64 sites), lotic (EUNIS C2; 99 sites) and highly artificial (EUNIS J5; 18 sites) habitats. The aim of the study was to test whether the overall number of alien species and the proportion of alien species for each taxonomic group differed between habitat types and could be explained by environmental, human-mediated, or climatic factors. Using generalized linear mixed effect models to account for potential confounding factors, only average air temperature of the site was a significant positive predictor of the occurrence of alien species, regardless of habitat type, species richness, and other climatic variables. A direct effect of temperature could be excluded given the origin of alien species, mostly from colder areas than Italy. Thus, an indirect effect could be hypothesized at the Italian latitudes, with warmer areas potentially more likely to be visited by tourists than colder areas. If this hypothesis is confirmed, the results of the analyses call for a compromise between the maintenance of recreational activities in the wild and the preservation of a natural environment to prevent the arrival and spread of alien species. On the other hand, no further recommendations can be implemented regarding habitat susceptibility to alien species. © 2014 John Wiley & Sons, Ltd.