6.7 Environmental considerations

A number of problems affect fisheries and aquaculture in coastal lagoons in Italy, and most are related to environmental constraints of these ecosystems. Most of these constraints are not recent, and have been extensively described (Ardizzone et al., 1988; Marino et al., 2009), but the resolution of environmental problems is not easy, probably because of a lack of integration between ecological knowledge and their rendering in strategies and plans related to lagoon management.

The functionality of many coastal lagoons depends on the interactions between anthropogenic impacts and natural phenomena, which may influence the ecosystem dynamics and affect the trophic status of the lagoon, influencing productivity and sometimes the conservation and even survival of lagoon living resources. The permanence and preservation of the lagoon system thus depends on the physical characteristics and the status of biological resources in the area (inside and outside the lagoon), but also on the human activities carried out to improve lagoon morphology, hydrology and trophic status in these coastal ecosystems. Periodic dystrophic phenomena are a natural occurrence for many lagoons and represent the main cause of aquatic fauna mortalities and loss of fish product (Izzo and Hull, 1991).
A major environmental issue is the increasing pollution from freshwater inputs to coastal lagoons, particularly heavy where the exchanges with the sea are reduced or absent. The 2005 Report of the Italian Ministero dell’Ambiente e della Tutela del Territorio defined the Orbetello lagoon, the Comacchio valli, the Po delta, the Lesina and Varano lakes and the Latium coastal lakes as sensitive areas (art. 18, D.Lgs. 152/99). At present, the trophic state of many Italian coastal lagoons is increasing as a result of inputs of organic pollutants. Among the stressors, nitrogen rather than phosphorus loadings seems to have increased over time (Vitousek et al., 1997; Howarth and Marino, 2006). In well-managed lagoons, this situation can lead to a growing trend in fish yield (Kapetsky and Lasserre, 1984) as in the Orbetello lagoon, but only too often it leads to a dystrophic state with periodic mass mortalities (Ardizzone, 1985).

In some lagoons, increased eutrophication is due to aquaculture and agricultural activities, as well as the discharge of treated/untreated urban wastewater. This has brought about qualitative and quantitative changes in the vegetation. Changes from seagrasses (phanerogams) to macroalgae and macroalgal blooms have been widely observed in Italian coastal lagoons, sometimes coupled with microalgal blooms. When blooms impair the penetration of the light through the water column, preventing photosynthesis, anaerobic degradation of organic matters is triggered. Dystrophic crises often occurred in the past in the Orbetello lagoon and in deeper lagoons where water circulation is reduced in the water column: examples are the lagoons of Sabaudia, Fondi and Lungo (Ardizzone et al., 1988), but also in shallower lagoons such as many Sardinian ponds.
Lagoons are ultimately under strong anthropogenic pressure from watersheds, as they receive freshwater input, rich in organic and mineral nutrients drained from heavily exploited catchments and from the surrounding urban and industrial settlements (see, for example, the Venice lagoon). Heavy metals (Cr, Cd, Cu, Pb, Zn, As, Hg) in both the upper and lower sediment layers (Franchi et al., 2003; Giordano et al., 2003) are some of the xenobiotic substances found in certain Italian coastal lagoons. PCBs have been found in eels from many coastal lagoons (Mariottini et al., 2006; Bettinetti et al., 2010). All these anthropogenic pressures are responsible for important ecosystem alterations, i.e. eutrophication, bacterial contamination, algal blooms (toxic or not), anoxia and fish mortality, and the possible presence of contaminants in fish.
Local stressors have also combined with global processes. The Intergovernmental Panel on Climate Change (IPCC) report (2001) predicts an annual temperature increase in the Mediterranean area of between 0.2 and 0.6 °C per decade, an increase in short and intense precipitations and a greater seasonal differentiation in precipitation, with an increase of up to 4 152 percent in winter and a decrease of up to 5 percent in summer. Further, additional problems are caused by coastal erosion, subsidence and effects related to extreme meteorological events, typical of Mediterranean areas.
The protection of piscivorous birds led to a considerable increase in their populations; in several regions they have reached a level at which they cause heavy economic losses to most coastal lagoon fisheries and extensive aquaculture throughout Italy. Predation by ichthyophagous birds, in particular cormorants, is a main effect when the fish are in the wintering ponds in the valli.
Overfishing in coastal areas has led to a reduction of natural fish recruitment to lagoons, and also to a reduced availability of seed for restocking, an important practice to sustain fish production in the vallicoltura. This is particularly true for eel, a species typical of Italian, and Mediterranean, coastal lagoons.
Other constraints, for example in Sardegna, are linked to a progressive loss of the capacity to manage water exchanges between lagoon and sea, which brings about consequences on the stocks of euryhaline fish species migrating between sea and lagoons.
Most lagoons in Italy suffer from the consequences of general environmental changes linked to coastal erosion, subsidence, extreme meteorological events recently amplified (wider precipitation levels between seasons).
Other sources of constraints are linked to market, such as competition with intensive fish production, lack of continuity in market supply compared with the intensive product, lack of specific labels adding value to lagoon products and an inadequate legislative framework.
Acknowledgements
The author is grateful to Stefano Cataudella, Lorenzo Tancioni, Piero Franzoi, Alessandra Cannas, Michele Pellizzato and Donatella Crosetti for providing useful data and information on Italian coastal lagoons, and to Marco Dell’Aquila, Unimar, for the support in the GIS control of the Italian lagoons.

6.8 References

Ardizzone, G.D., Cataudella, S. & Rossi, R. 1988. Management of coastal lagoon fisheries and aquaculture in Italy. FAO Fisheries Technical Paper No. 293. Rome, FAO. 103 pp. Ardizzone, G.D. 1985. Analysis of the fisheries of the central Tyrrhenian Sea. FAO Fisheries Report No. 362, 51–60.
Basset, A., Sabetta, L., Fonnesu, A., Mouillot, D., Do Chi, T., Viaroli, P., Giordani, G., Reizopoulou, S., Abbiati, M. & Carrada, G.C. 2006. Typology in Mediterranean transitional waters: new challenges and perspectives. Aquatic Conservation: Marine and Freshwater Ecosystems, 16: 441–455.
Bettinetti, R., Galassi, S., Quadroni S., Volta P., Capoccioni, F, Ciccotti, E. & De Leo, G.A. 2010. Use of Anguilla anguilla for biomonitoring persistent organic pollutants (pops) in brackish and riverine waters in central and southern Italy. Water Air Soil Pollution, doi: 10.1007/s11270-010-0590-y.
Boatto, V. & Signora, W. 1985. Le valli da pesca nella laguna di Venezia. Padova. 260 pp. Brambati, A. 1988. Lagune e stagni costieri: due ambienti a confronto. In G.C. Carrada, F. Cicogna & E. Fresi, eds. Le lagune costiere: ricerca e gestione, pp. 9–33. Massa Lubrense (Naples), Italy, CLEM Pubbl.
Brunelli, G. 1916. Ricerche sul novellame dei muggini con osservazioni e considerazioni sulla mugginicoltura. Memoria. R. Comitato Talassografico Italiano No. 54. 45 pp. Brunelli, G. 1933. La coltivazione degli stagni salsi e la vallicoltura. Bollettino di Pesca, Piscicoltura e Idrobiologia, 9(5): 791–798.
Bucci, M., Gorelli, V. & Vincenzi, D. 1989. Metodologia d’intervento per la caratterizzazione 153
idrodinamica della laguna di Orbetello. Attivita 1987-1988. RT/PAS/89/18: 10-60, ENEA, Casaccia, Roma.
Bullo, G. 1891. Piscicoltura marina. Stima delle coltivazioni in acqua salsa (Parte 1. Notizie preliminari). Stabilimento Prosperini. Padova.
Bullo, G. S. 1940. Le valli salse da pesca e la vallicultura. Venezia, Officine grafiche Carlo Ferrari. 186 pp.
Cannas, A., Cataudella, S. & Rossi, R. 1995. Gli stagni della Sardegna. Quaderni C.I.R.S.P.E. 96 pp.
Cataudella, S. & Tancioni, L. 2007. Direttiva per le acque e impatto sul settore della pesca. In R. Zucaro. Direttiva Quadro per le acque 2000/60 – Analisi dell’impatto sul settore irriguo e della pesca, pp. 151–160. Roma, Istituto Nazionale di Economia Agraria.
European Commission. 1992. Council Directive 92/43/EEC of 21 May 1992 on the conservation of natural habitats and of wild fauna and flora. Brussels.
European Commission. 2000. Directive 2000/60/EC of the European Parliament and of the Council establishing a framework for the Community action in the field of water policy. Brussels.
European Commission. 2007. Council Regulation (EC) No 1100/2007 of 18 September 2007 establishing measures for the recovery of the stock of European eel, 22.09.2007, L 248, 17-23. Brussels.
European Commission. 2009. Directive 2009/147/EC of the European Parliament and of the Council of 30 November 2009 on the conservation of wild birds.
Ceccarelli, R., Moretti, F., Bardi, A., Giunti, M. & Minucci, G. 2009. Fishery and cormorant interaction in the Orbetello lagoon. Presented at the III Congresso LaguNet, Orbetello, 1- 4 Ottobre 2009.
Ciccotti, E., Busilacchi, S. & Cataudella S. 1999. La pesca delle cieche di anguilla, tra conservazione ed uso responsabile. Laguna (suppl.), 6/99: 94–127.
Ciccotti, E. 2005. Interactions between capture fisheries and aquaculture: the case of the eel (Anguilla anguilla L., 1758). In S. Cataudella, F. Massa & D. Crosetti, eds. Interactions Between Capture Fisheries And Aquaculture: A Methodological Perspective, pp. 190– 203. Studies and Reviews. General Fisheries Commission for the Mediterranean. No. 78. Rome.
De Wit, R., Mostajir, B., Trousselier, M. & Do Chi, T. 2007. Environmental management and sustainable use of coastal lagoons ecosystems. In A.G. Froiedman, ed. Lagoons: Biology, Management and Environmental Impact, pp. 333–350. Nova Science Publishers.
Donati, F., Vasciaveo, M., Zoppelletto, M., 1999. Valutazione dell’impatto socioeconomico della pesca del novellame nel contesto della filiera produttiva delle valli da pesca. La pesca del novellame, Laguna (suppl.), 6: 79–93.
Fabris, A.1991. Valle Figheri. Storia di una valle salsa da pesca della laguna veneta. Venezia, Filippi Editore. 141 pp.
Fontolan, G., Orel, G., Pessa, G. & Zentilin, A. 1995. Modificazioni indotte dalla venericoltura sulla struttura dei sedimenti e dei popolamenti macrozoobentonici della laguna di Marano. In M. Berletti, R. Rossi & E. Spreafico. PIM per le zone lagunari e l’Adriatico settentrionale. Ricerche e Sperimentazioni 1988-1994, pp. 231–243. Mestre, Italy, Regione del Veneto, Segretaria per le Attivita Produttive ed Economiche del Settore Primario.
Franchi, E., Volterrani, M., Renzi, M., Balocchi, C.& Focardi, S. 2003. Sedimentch caracterization of various areas of the Orbetello lagoon impacted by differing degrees and types of contamination input. In C.N. Murray, J.M. Zaldivar, G. Giordani & P. Viaroli. Proceedings of the International Conference on Southern European Coastal Lagoons: The Influence of River Basin-Coastal Zone interactions. Castello Estense (Ferrara, Italy). Joint Research Centre, European Commission, Ispra (VA). 151 pp.
154
Franco, A., Franzoi, P., Malavasi, S., Riccato, F. & Torricelli, P. 2006. Use of shallow water habitats by fish assemblages in a Mediterranean coastal lagoon. Estuarine Coastal and Shelf Science, 66: 67–83.
Franco, A., Franzoi, P., Malavasi, S., Riccato, F. & Torricelli, P. 2006. Fish assemblages in different shallow water habitats of the Venice Lagoon. Hydrobiologia, 555: 159–174 Franco, A., Malavasi, S., Zucchetta, M., Franzoi, P. & Torricelli, P. 2006. Environmental influences on the fish assemblage of the Venice Lagoon, Italy. Chemistry and Ecology, 22: S105–S118.
Franzoi, P., Penzo, P. & Pellizzato, M. 2002. Vallicoltura e pesca del pesce novello. In M. Pellizzato Pesci. Molluschi e crostacei della laguna di Venezia, risorse ittiche e ambiente lagunare tra storia e innovazione, pp. 99–129. Provincia di Venezia, Cicero Venezia.
Giordano, P., Matteucci, G., Frasari, F. & Ascanelli, M. 2003. Contamination aspects by toxic metals in shallow coastal lagoon bottom sediments: Fattibello-Spavola, Northern Adriatic Sea, Italy. Proceedings of the International Conference on Southern European Coastal Lagoons: The Influence of River Basin-Coastal Zone Interactions. Castello Estense, Ferrara, Italy, 10–12 November 2003. Special Publication No.I.03.136. 44 pp.
Granzotto, A., Franzoi, P., Longo, A., Pranovi, F. & Torricelli, P. 2001. La pesca nella Laguna di Venezia: un percorso di sostenibilita nel recupero delle tradizioni. Lo stato dell’arte. Rapporto sullo sviluppo sostenibile 2. Fondazione Enrico Mattei. 60 pp.
Howarthm, R.W. & Marino, R. 2006. Nitrogen as the limiting nutrient for eutrophication in coastal marine ecosystems: evolving views over three decades. Limnology and Oceanography, 51: 364–376.
Innamorati, M. & Melillo, C. 2004. Studio della Laguna di Orbetello: ecologia ed aspetti economic [online]. Laboratorio di Ecologia, Dipartimento di Biologia Vegetale, Universita di Firenze. [Cited 4 May 2009]. http://eprints.unifi.it/archive/00001260/.
Intergovernmental Panel on Climate Change (IPCC). 2001. Working Group II: Impacts, Adaptation and Vulnerability. Intergovernmental Panel on Climate Change. [online]. Geneva. [Cited 4 January 2014]. www.ipcc.ch/.
Izzo, G. & Hull, V. 1991. The anoxic crises in dystrophic processes of coastal lagoon: an energetic explanation. In C. Rossi & E. Tiezzi, eds. Ecological Physical Chemistry, pp. 559–572. Amsterdam, Elsevier Sci.Pb.
Kapetsky, J.M. & Lasserre, G. 1984. Management of Coastal Lagoon Fisheries (Mediterranean). In GFCM, 1984. Expert Consultation on the Management of Coastal Lagoon Fisheries, Rome (Italy), 12 September 1983. Studies and Reviews. General Fisheries Council for the Mediterranean. No. 61. Rome, FAO. 797 pp.
Lenzi, M. & Salvatori, R. 1986. Eutrofizzazione, distrofie e produzione ittica nella Laguna di Orbetello. Atti Mus. Civ. Stor. Nat. Di Grosseto, 9/10: 45–55.
Libralato, S., Pranovi, F., Torricelli, P., Raicevich, S., Da ponte, F., Pastres, R. & Mainardi, D. 2004. Ecological stages of the Venice Lagoon anaysed using landing time series data. Journal of Marine Systems, 51: 331–334.
Marino, G., Boglione, C., Livi, S. & Cataudella, S. 2009. National Report of estensive and semi-intensive production practices in Italy. Seacase EU project n. 044483, Deliverable 20. 88 pp.
Mariottini, M., Corsi, I. & Focardi, S. 2006. PCB levels in European eel (Anguilla anguilla) of the Mediterranean. Environmental monitoring and assessment, 117(1-3): 519–528. Neotron. 2006. Analisi di dettaglio dell’attivita delle aziende vallive della Provincia di Venezia. Relazione Tecnica. 50 pp.
Pellizzato, M., Favretto, J., Galvan T. & Penzo, P. 2006. Produzione alieutica in laguna di Venezia. Biol. Mar. Medit., 13: 897–900.
Persona, R., Schiavon, M. & Panizon R. 1996. Commercio e canali distributivi di brazino e orata. L’Informatore Agrario, 3735. 44 pp.
155
Pranovi, F. & Giovanardi, O. 1994. The impact of hydraulic dredging for short-necked clams, Tapes spp., on an infaunal community in the Venice Lagoon. Scientia Marina, 58: 345– 353.
Pranovi, F., Giovanardi, O. & Franceschini, G. 1998. Recolonisation dynamics in areas disturbed by bottom fishing gear. Hydrobiologia;375/376:125–135.
Provincia di Venezia. 1998. Piano per la gestione delle risorse alieutiche delle lagune della Provincia di Venezia. Provincia di Venezia Technical report. 188 pp.
Provincia di Venezia. 1999. Piano per la gestione delle risorse alieutiche delle lagune della provincia di Venezia. Documento pianificatorio Assessorato alla caccia, pesca e polizia provinciale, a cura di Orel G., Boatto V., Sfriso A., Pellizzato M., 180. pp.
Provincia di Venezia. 2000. Piano per la gestione delle risorse alieutiche delle lagune della provincia di Venezia. Sannioprint, Benevento. 102 pp.
Provincia di Venezia. 2008. Norme per l’esercizio della pesca nelle acque interne e marittime interne. Spinea Venezia, Multigraf srl. 95 pp.
Provincia di Venezia. 2009. Piano per la gestione delle risorse alieutiche delle lagune di Venezia e Caorle. A cura di: Torricelli P., Boatto V., Franzoi P., Pellizzato M., Silvestri S, AGRI.TE.CO sc., Ed. Arti Grafiche Zotelli, Dosson di Casier (TV), 203 pp.
Rossi, R. &Franzoi, P. 1999. La tecnica di pesca del pesce novello da semina. La pesca del novellame. Laguna (suppl.), 6: 31–37.
Rossi Doria, M. & Bevilacqua, P. 1984. Le bonifiche in Italia dal ‘700 ad oggi. Bari, Ed. Laterza.
Rossi, R. 1986. Occurence, abundance and growth of fish fry in Scardovari Bay, a nursery ground of the Po River delta (Italy). Archivio di Oceanografia e Limnologia, 20: 259–279. Tagliapietra, D. & Volpi Ghirardini, A. 2006. Notes on coastal lagoon typology in the light of the EU Water Framework Directive: Italy as a case study. Aquatic Conservation: Marine and Freshwater Ecosystems, 16: 457–467.
Unimar. 2009. Censimento acquacoltura.
Valloni, R., Barsanti, M., & Ferretti, O. 2006. Tipi geologici e distribuzione geografica degli specchi d’acqua costieri italiani. Lagune. Laghi e invasi artificiali italiani. Atti dei Convegni Lincei 222 – Giornata Mondiale dell’Acqua. Roma, 22 marzo 2005: 201–209. Accademia Nazionale dei Lincei.
Vitousek, P.M., Aber, J.D., Howarth, R.W., Likens, G.E., Matson, P.A., Schindler, D.W., Schlesinger, W.H. & Tilman D.G., 1997. Human alteration of the global nitrogen cycle: sources and consequences. Ecological Applications, 7: 737–750.