MAQI LAGOON OF VENICE (MACROPHYTE QUALITY INDEX)

    Descrizione 1
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    Authors

    Valentina Bernarello, Andrea Bonometto, Rossella Boscolo Brusà, Federica Cacciatore, Federica Oselladore, Emanuele Ponis

    Abstract
    Immagine
    Abstract

    The MaQI (Macrophyte Quality Index) (Sfriso et al., 2014) formally adopted by Italy for the classification of the ecological status of transition environments under Directive 2000/60/EC, integrates the two organic quality elements macroalgae and aquatatal fanerogages. 
    The MaQI responds to anthropogenic pressures affecting transition areas and describes the ecological quality status in 5 classes: high, good, sufficient, scarce and bad.
    The monitoring of macrophytes for the application of the MaQI index has been active in the Venice Lagoon since 2011 with a three-year frequency. In the three-year period 2020-2022 (21 data) of the eleven natural water bodies of the Venice Lagoon, two were in a “high” state, four in a “good” state, three “sufficient” and two in a “poor” state. The trend, although statistically not significant, is overall positive, considering the improvement of the state of some bodies of water.

    Description

    The Macrophyte Quality Index is a multimetric index, based on: number and percentage of sensitive macrolagal species; relative abundance of Rhodophyta and Chlorophyta; percentage coverage of macroalgae; percentage coverage of the different species of aquaetal fanerogate (ISPRA, 2011). 
    This index is used to provide a synthetic ecological classification of the ecosystem through the use of the structural parameters (coverage, composition and abundance) of the mobile background macrophytic community. The MaQI, consolidated by a robust bibliographic support, is able to summarize the complexity of the mobile bottom plant communities, allowing an ecological reading of the ecosystem in question.
    The index is applicable to all Italian water bodies with an average annual salinity of more than 5 and has been intercalibrated with other Member States to ensure the comparability of the results at Mediterranean level.
    The value of the MaQI varies between 0 and 1, and corresponds to the Ecological Quality Report (RQE) required by the Water Framework Directive 2000/60/EC. Class limits are defined and reported in the reference legislation DM 260/2010.
    The application of the index in the Lagoon of Venice takes place through the calculation of the average RQE values of the stations of each of the eleven natural water bodies according to which the lagoon was divided: EC – Palude Maggiore, PC1 – Dese, PC4 –Teneri, PC2 – Millecampi, PNC1 – Marghera, PNC2 – Tessera, ENC2 – Bocca di Lido, ENC4 – Sacca Sessola, ENC1 – Centro Sud, ENC3 – Chioggia, PC3 – Val di Brenta.

    Purpose

    Classify the ecological quality status of transitional water bodies using the biological quality elements "macroalgae" and "aquatic blush".

    Policy relevance and utility for users
    It is of national scope or it is applicable to environmental issues at the regional level but of national relevance.
    It can describe the trend without necessarily evaluating it.
    It is simple and easy to interpret.
    It is sensitive to changes occurring in the environment and/or in human activities
    It provides a representative picture of environmental conditions, environmental pressures, and societal responses
    It provides a basis for international comparisons.
    Ha una soglia o un valore di riferimento con cui può essere confrontato
    Analytical soundness
    Be based on international standards and international consensus about its validity;
    Be theoretically well founded in technical and scientific terms
    Presents reliability and validity of measurement and data collection methods
    Temporal comparability
    Spatial comparability
    Measurability (data)
    Adequately documented and of known quality
    Updated at regular intervals in accordance with reliable procedures
    Readily available or made available at a reasonable cost/benefit ratio
    An “adequate” spatial coverage
    An “appropriate” temporal coverage
    Main regulatory references and objectives

    Directive 2000/60 / EC
    D.Lgs. 152/2006 and ss.mm.i.i
    Decision 2018/229 / EU
    Directive 2000/60/EC (received by Legislative Decree 152/2006 and subsequent amendments) establishes a regulatory framework for all Member States, for the protection of inland surface water, transitional waters, coastal and underground waters that aims at the improvement and restoration of all surface water bodies, for artificial water bodies and those strongly modified, in order to achieve a good state of the surface waters.  
    The MaQI index has been formally identified for the classification of the Macrophyte Biological Quality Element in Italian transitional waters by DM 260/2010 and included in Decision 2018/229/EU following the intercalibration process in the Mediterranean.

    DPSIR
    State
    Indicator type
    Descriptive (A)
    References

    Sfriso, A., Facca, C., Ghetti, P.F. (2007). Rapid Quality Index, based mainly on Macrophyte Associations (R-MAQI), to assess the ecological status of the transitional environments. Chemistry and Ecology, 23 (6): 1-11.
    Sfriso, A., Facca, C., Ghetti, P.F. (2009). Validation of the Macrophyte Quality Index (MaQI) set up to assess the ecological status of Italian marine transitional environments. Hydrobiologia, 617, 117-141. 
    Sfriso, A., Facca, C., Bonometto, A., Boscolo, R. (2014). Compliance of the Macrophyte Quality Index (MaQI) with the WFD (2000/60/EC) and ecological status assessment in transitional areas: The Venice lagoon as study case. Ecological Indicators 46, 536–547.
    ISPRA, 2009. Implementazione della Direttiva 2000/60/CE - Classificazione dello stato ecologico dei corpi idrici delle acque marino costiere e di transizione.
    ISPRA, 2010. Implementazione della Direttiva 2000/60/CE - Linea guida per l’applicazione dell’indice MaQI.
    ISPRA, 2011. Protocolli per il campionamento e la determinazione degli elementi di qualità biologica e fisico-chimica nell’ambito dei programmi di monitoraggio ex 2000/60/CE delle acque di transizione. 
    ISPRA-UNIVE, 2012. Variazioni del Macrophyte Quality Index (MaQI) a seguito dei risultati dell’intercalibrazione nell’Ecoregione Mediterranea (Med-GIG).

    Further actions

    Constant updating of the species list used.

    Frequenza di rilevazione dei dati
    Frequenza variabile
    Fonte dei dati
    ARPAV (Arpa Veneto)
    SINTAI
    Data availabilty

    www.arpav.it

    Spatial coverage

    The Lagoon of Venice

    Time coverage

    2011-2013; 2014-2016; 2017-2019; 2020-2022

    Processing methodology

    or the application of the MaQI it is necessary to determine the following parameters:
    - Systematic recognition of macroalgal taxa at the species level and determination of the number and percentage of sensitive taxes present (ISPRA, 2010);
    - Total coverage and relative abundance of the dominant macroalgae. It is sufficient to discriminate between the 5% or ? coverage and the relative abundance of Chlorophyta and Rhodophyta;
    - Relative percentage recognition and coverage of individual species of phanerow.
    The metrics are combined with each other via a two-way matrix, for macroalgae and fanerogames respectively, which directly returns the value of the RQE and the state of the EQB (ISPRA, 2012). The value of the MaQI varies between 0 and 1. The class limits are reported in the reference legislation (Legislative Decree 152/2006 and ss.mm.ii.), which defines 5 classes (high, good, sufficient, scarce, bad).

    Update frequency
    Three-year
    Qualità dell'informazione

    The indicator responds to the request to classify the ecological status of the transition environments through the use of macrophytes. The data source (ARPAV) ensures accuracy and reliability of the evaluation. Its application is complete in spatial terms since the three-year period 2011-2013. The continuation of the monitoring pursuant to Directive 2000/60/EC in all Italian transition environments will allow the application of the indicator by all ARPA/APPA: in this way the comparability of data over time and space will be guaranteed, also through the use of the same sampling, analysis and classification methodology. Compliance with the Directive also requires that the reliability of data sources and their validation be ensured.

    State
    Medium
    Trend
    Positive
    State assessment/description

    From the analysis of the MaQI index at the body of water body, it is observed that in the three-year period 2020-2022 (data 2021) 2 water bodies are in the “poor” ecological state, 3 “sufficient”, 4 “good” and 2 in “high” state (Figure 1).

    Trend assessment/description

    There are 9 out of 11 bodies of water that throughout the period analyzed (2011-2022) show an increase in the values of the MaQI index, in some cases with an improvement in the quality class (Figure 2). Compared to the previous three-year period (2017-2019) the water bodies in “poor” state decreased (from 5 to 2) and increased those in sufficient state (from 2 to 3), good (from 3 to 4) and elevated (from 1 to 2) (Figure 2).  
    The trend, although not statistically significant (Her Kendall test with p-0.05 for all CIs), from a purely descriptive point of view, seems to show an improvement in the quality of the bodies of water over the years, throughout the Lagoon, except for the central area propying the industrial area of Porto Marghera (PNC1) water body, the area of the Teneri (PC4 water body) and the water body influenced by the river Dese1. For all three bodies the classifications remain unchanged compared to the previous three years. 
    The EC-Submpus Major water body constantly increases RQE values from 2011 to 2019 going from “sufficient” to “high”, quality class that is maintained as such in 2021, albeit with a decrease in RQE scores. 
    ENC2 – Bocca di Lido improves in class, from “sufficient” to “good”, between 2011 and 2014. In the following monitoring (2019 and 2021) the “good” state is reconfirmed. ENC1 was “good” from 2011 to 2019 and in the last monitoring cycle it improves until it reaches the “high” state.
    From 2014 to 2019, the water body ENC3 - Chioggia improves from "sufficient" to "good" and remains so in 2021.
    PC2 – Millecampi and PNC2 – Card, which do not have a variation in the allocation class in the 3 monitoring cycles from 2011 to 2019 (they always remain in a “poor” state), however, show a constant increase in RQE values until they reach the “good” state for PC2 and the “sufficient” state for PNC2 in 2021. ENC4 – Sacca Sessola also remains in quality “poor” in the first three years, until it passes to “good” in 2021. Finally, PC3 – Val di Brenta remains “poor” in the first three-year period and improves in the state of “sufficient” in the last three years (Figure 2).

    Comments

    The application of the MaQI index in the water stations and bodies of the Venice Lagoon provides a general assessment of the macrophytic component for the year 2021, referring to the entire three-year period 2020-2022 (Figure 1).
    In the three-year period 2020-2022 (21st data), based on the EQB Macrofite (macroalgae and aquatic fanerogages) were in a “good” or “high” state 6 water covers (ENC1, ENC2, ENC3, ENC4, EC and PC2) out of 11. The ecological conditions of macrophytes generally appear to be improving with an increase in RQE in almost all water bodies, except for EC, ENC2, PC1, PC4, and PNC1 (which do not change the quality state) (Figure 2).

    Data
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    Figure 1: Application of the MaQI index in the water stations and bodies of the Venice Lagoon (three-year period 2020-2022)

    Data source

    ISPRA - ARPAV

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    Headline

    Figure 2: Box plot of MaQI values determined in 2011, 2014, 2019 and 2021 in the water bodies of the Venice Lagoon

    Data source

    ISPRA - ARPAV

    Data legend

    EQR = Ecological Quality Ratio. The colored bands correspond to the limits defined by Legislative Decree 152/2006 ss.mm.ii (blue = high, green = good, yellow = sufficient, orange = poor, red = bad)

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