15 research outputs found
Using local ecological knowledge to search for non-native species in Natura 2000 sites in the central Mediterranean sea : an approach to identify new arrivals and hotspot areas
The management of biological invasions is among the most urgent of global challenges and requires a significant monitoring effort to obtain the information needed to take the appropriate decisions. To complement standard monitoring, citizen science is increasingly being used. Within citizen science, the approach of collecting and investigating Local Ecological Knowledge (LEK) proved to be useful in the monitoring of non-native species. A LEK survey was carried out in 10 Sicilian and Maltese Natura 2000 sites in order to help in the early detection of non-native species. The survey was addressed to local fishers and SCUBA divers in order to investigate the occurrence of 24 selected marine non-native species and to identify potential hotspot areas of invasion through the use of six indicators: the occurrence of newly introduced nonindigenous species, the cumulative impacts of invasive alien species (CIMPAL) and the relative importance of species on the cumulative impacts (D1, D2, D3, and D4). The respondents confirmed the presence of 22 species since the year 2000 and reported 10 new ones registered in the investigated areas. The highest CIMPAL value was observed in two Sicilian Natura 2000 sites (ITA090028 and ITA040014) and the lowest on the western coast of Malta (MT0000101, MT0000102, MT0000103, and MT0000104) The four top-priority species according to indicators D1–D4 were Caulerpa cylindracea, C. taxifolia, Siganus luridus and S. rivulatus. The study produced a valid and useful scientific output to suggest and address management strategies to monitor the establishment of the non-native species.peer-reviewe
General theory of the fuzzy integral
By means of two general operations and , called ``pan-operations'', we build a new kind of integral. This formulation contains, as particular cases, both Choquet's and Sugeno's integrals
General theory of the fuzzy integral
By means of two general operations and , called ``pan-operations'', we build a new kind of integral. This formulation contains, as particular cases, both Choquet's and Sugeno's integrals
Comonotone aggregation operators
We consider the aggregation operators which are comonotone-
\oplus additive.The main result is a representation theorem which expresses any operators by means of a kind of general fuzzy integral.This expression uses a family of fuzzy measures linked by a \oplus Cauchy equation
General theory of the fuzzy integral
By means of two general operations and , called ``pan-operations'', we build a new kind of integral. This formulation contains, as particular cases, both Choquet's and Sugeno's integrals
Divergence and fuzziness measures
In axiomatic way, a divergence among fuzzy sets is introduced which extends the symmetric difference among crisp sets. Any fuzzy measure of the divergence between toe fuzzy sets weights their "distance." The distance between a fuzzy set and the family of crisp sets is a fuzziness measure