Page 4 - Caruso_Zaccone_2000
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954  G. CARUSO AND R. ZACCONE




                                 (a)     –1  –1        (b)     –1  –1       (c)     –1  –1
                                     µg C l  h             µg C l  h            µg C l  h
                                 0              10     0      1       2      0      1      2
                                0                     0                    0


                                                                           5
                                5                     5
                                                                           10
                              Depth (m)  10          10                    15




                                                                           20
                               15                    15

                                                                           25

                               20                    20                    30


          Fig. 3 The Adriatic Sea (Prisma 1 project): vertical pro®les of LAP activity at two coastal sites, Station S1 (a) and Station S2 (b), affected
          by Po and Adige river runoff, and at one off-shore station, S3 (c), sampled in April (W), July (&) and October (~), respectively. Error
          bars indicate S.D. from the mean value (n ˆ 3)





          from coastal to off-shore stations, the spatial distribution of  ferences among areas (F ˆ 541, P < 005, n ˆ 116), seasons
          LAP was characterized in both areas by a decreasing trend,  (F ˆ 348, P < 005, n ˆ 60) and years (F ˆ 939, P < 005,
          in agreement with the trophic gradient but inverse to the  n ˆ 60).
          salinity gradient.                                     As far as the relationship between LAP and some biotic
            Enzyme activity varied on a seasonal scale, with average  and abiotic parameters is concerned (Table 2), Pearson cor-
          values 15 times higher in summer than in winter. The  relation coef®cients showed that LAP levels were some-
          ANOVA test, however, did not reveal any signi®cant dif-  times signi®cantly related to viable heterotrophic bacterial





           Table 1 The Adriatic Sea (Prisma 1 project). Coef®cients of correlation between LAP and the main physico-chemical and
          microbiological data recorded in surface and along the water column at two coastal sites (S1 and S2) and at one off-shore station (S3),
          respectively. In parenthesis the number of pairs of data is reported
                                  Station S1            Station S2           Station S3
                                                                                                  All surface data
                                            Water                Water                Water
                                  0 m (3)   column (14)  0 m (3)  column (14)  0 m (3)  column (15)  (9)

          Temperature               083      045        082    037       ÿ 093   009          040
          Salinity                  043      035      ÿ 089    028         023   051         ÿ009
          Viable heterotrophic bacteria  * 0996  ** 089  004   010       * 0990  037        ** 093
          Bacterial carbon production  ** 0999  ** 097  ** 0999  038       027   022        ** 097
          Chlorophyll a             078    ** 090       043    022       * 0993  010         * 079
          POC                                *098               ÿ008                013
          *Signi®cant value at P < 005; **Signi®cant value at P < 001.

                                              = 2000 The Society for Applied Microbiology, Journal of Applied Microbiology, 89, 951ÿ959
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