The Ramsar Convention on Wetlands
COME "NASCE" LA CONVENZIONE DI RAMSAR
Il Consiglio d’Europa,
nel 1970, in occasione dell’Anno della conservazione della natura, emana la
"Carta dell’acqua", contenente i principi basilari per la tutela e
la gestione delle zone umide.
Lo stesso Consiglio d’Europa, nel 1976 proclama l’Anno Europeo delle zone
umide, per sensibilizzare i cittadini e sostenere la Convenzione di Ramsar (http://www.iucn.org/themes/ramsar/index_global.htm)
La "Convenzione per la salvaguardia delle zone umide di interesse internazionale soprattutto come habitat degli uccelli acquatici" è stata elaborata durante una Conferenza internazionale tenutasi all’inizio del 1971 a Ramsar (Iran), la cui organizzazione venne curata:
dall’IWRB
della FAO
dell’UNESCO
del CIC
l’ICBP (International Council for Birds Preservation),
l’IUCN (International Union for Conservation of Nature and Natural Resources) ed il
WWF
Il Governo Italiano ha ratificato tale Convenzione col DPR n. 448 del 1976, entrato in vigore il 15 aprile 1977.
Il nostro Paese ha quindi indicato all’IUCN le zone umide da inserire nell’Elenco delle zone umide di importanza internazionale, sulla scorta dei CRITERI DI SCELTA perfezionati negli anni 80 in alcuni convegni scientifici, che riguardano sia la quantità e la qualità della fauna ornitica presente, ma anche la peculiarità della flora e della fauna, come ad esempio la presenza di endemismi.
L’Italia è stata particolarmente attiva nello sforzo di protezione delle proprie zone umide, identificandone per ora 46, per oltre 50.000 ha.
L’inserimento fra le aree protette a norma della Convenzione di Ramsar impegna lo Stato a
ZONE UMIDE ITALIANE
The Criteria for Identifying Wetlands of International Importance
A wetland is identified as being of international importance if it meets at least one of the 4 criteria set out below:
1. Criteria for representative or unique wetlands
A wetland should be considered internationally important if:
(a) it is a particularly good representative example of a natural or near-natural wetland, characteristic of the appropriate biogeographical region; or
(b) it is a particularly good representative example of a natural or near-natural wetland, common to more than one biogeographical region; or
(c) it is a particularly good representative example of a wetland which plays a substantial hydrological, biological or ecological role in the natural functioning of an major river basin or coastal system, especially where it is located in a trans-border position; or
(d) it is an example of a specific type of wetland, rare or unusual in the appropriate biogeographical region.
2. General criteria based on plants or animals
A wetland should be considered internationally important if:
(a) it supports an appreciable assemblage of rare, vulnerable or endangered species or subspecies of plant or animal, or an appreciable number of individuals of any one or more of these species; or
(b) it is of special value for maintaining the genetic and ecological diversity of a region because of the quality and peculiarities of its flora and fauna; or
(c) it is of special value as the habitat of plants or animals at a critical stage of their biological cycle; or
(d) it is of special value for one or more endemic plant or animal species or communities.
Endemic species: A species that is unique to one region, i.e. it is found nowhere else in the world. A group of fishes may be indigenous to a subcontinent with some species endemic to a part of that subcontinent.
3. Specific criteria based on waterfowl
A wetland should be considered internationally important if:
(a) it regularly supports 20,000 waterfowl; or
(b) it regularly supports substantial numbers of individuals from particular groups of waterfowl, indicative of wetland values, productivity or diversity; or
(c) where data on populations are available, it regularly supports 1% of the individuals in a population of one species or subspecies of waterfowl.
Significant proportion: In polar biogeographical regions a "significant proportion" may be 3-8 subspecies, species, families, life-history stages or species interactions; in temperate zones 15-20 subspecies, species, families, etc.; and in tropical areas 40 or more subspecies, species, families, etc, but these figures will vary between regions. A "significant proportion" of species includes all species and is not limited to those of economic interest. Some wetlands with a "significant proportion" of species may be marginal habitats for fish and may only contain a few fish species, even in tropical areas, e.g. the backwaters of mangrove swamps, cave lakes, the highly saline marginal pools of the Dead Sea.
The potential of a degraded wetland to support a "significant proportion" of species if it were to be restored also needs to be taken into account. In areas where fish diversity is naturally low, e.g. at high latitudes, in recently glaciated areas or in marginal fish habitats, genetically-distinct infraspecific groups of fishes could also be counted.
4. Specific criteria based on fish
A wetland should be considered internationally important if:
(a) it supports a significant proportion of indigenous fish subspecies, species or families, life-history stages, species interactions and/or populations that are representative of wetland benefits and/or values and thereby contributes to global biological diversity; or
(b) it is an important source of food for fishes, spawning ground, nursery and/or migration path on which fish stocks, either within the wetland or elsewhere, depend.
Fish: Any finfish, including jawless fishes (hagfishes and lampreys), cartilaginous fishes (sharks, rays, skates and their allies, Chondrichthyes) and bony fishes (Osteichthyes) as well as certain shellfish or other aquatic invertebrates, as listed below.
Indigenous species: A species that originates and occurs naturally in a particular place.
Life-history stage: A stage in the development of a finfish or shellfish, e.g. egg, embryo, larva, leptocephalus, zoea, zooplankton stage, juvenile, adult, post-adult.
Migration path: The route along which fishes, such as salmon and eels, swim when moving to or from a spawning or feeding ground or nursery. Migration paths often cross international boundaries or boundaries between intranational management zones.
Nursery: That part of a wetland used by fishes for providing shelter, oxygen and food for the early developmental stages of their young. In some fishes, e.g. nest-guarding tilapias, the parent/s remain at the nursery to protect the young whereas in others the young are not protected by the parent/s except by virtue of the shelter provided by the habitat in which they are deposited, e.g. non-guarding catfishes.
The ability of wetlands to act as nurseries depends on the extent to which their natural cycles of inundation, tidal exchange, water temperature fluctuation and/or nutrient pulses are retained; Welcomme (1979) showed that 92% of the variation in catch from a wetland-recruited fishery could be explained by the recent flood history of the wetland.
Spawning ground: That part of a wetland used by fishes for courting, mating, gamete release, gamete fertilization and/or the release of the fertilized eggs, e.g. herring, shad, flounder, cockles, and many fishes in freshwater wetlands. The spawning ground may be part of a river course, a stream bed, inshore or deep water zone of a lake, floodplain, mangrove, saltmarsh, reed bed, estuary or the shallow edge of the sea.
The freshwater outflow from a river may provide suitable spawning conditions on the adjacent marine coast.
Species interaction: Exchanges of information or energy between species that are of particular interest or significance, e.g. symbiosis, commensalism, mutual resource defence, communal brooding, cuckoo behaviour, advanced parental care, social hunting, unusual predator-prey relationships, parasitism and hyperparasitism. Species interactions occur in all ecosystems but are particularly developed in species-rich climax communities, such as coral reefs and ancient lakes, where they are an important component of biodiversity.
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