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In recent years, in response to the increased need of water resources for different uses, construction of artificial lakes has created many problems, causing an irreversible modification in the natural environment: the possibility of flooding over adjacent areas increases, new local climatic conditions are created, and there is a loss in water and sediment that should be given back to the river downstream. Moreover, the mean lifetime of artificial lakes is greatly shortened by the accumulation of sediments coming from the rivers feeding into them. Thus, maintenance of these particular habitats by means of periodical sediment removal is necessary in order to keep a satisfactory level of functionality. To resolve this problem, and in the meantime improve the quality of the surrounding environment, we propose a system, based on the integration of both classical and ecological engineering techniques, which is able to: (1) refurnish satisfactory reservoir volumes by removing sediments from the bottom; (2) provide the possibility of reusing these sediments; and (3) increase local biodiversity. The case study is located in Southern Italy, in the Basilicata Region, and involves the Camastra Reservoir.

In recent years the study of water quality in lakes and reservoir has been subject to several research programmes for both ecosystem evolution and water management. Analysis of hydraulic-environmental characteristics in terms of temporal trend has shown the hydraulics and physical-chemical structure of water but in terms of spatial distribution it is necessary to characterize the difference between point and non-point processes. A mobile monitoring system able to measure several vertical profiles along the reservoir surface and a geostatistical model are employed in order to evaluate the spatial (3-D) distribution of environmental indicators (temperature, dissolved oxygen, electrical conductivity, pH and redox potential). This approach has been demonstrated on the Camastra reservoir (Southern Italy). Through these computations the evolution of water thermal structure and hypolimnetic anoxic phenomena are described. The latter has been recognized to be dependent on the local hydraulic characteristics and not by diffuse anoxic processes.

We hypothesized that the negative functional effects of cyclic GMP (cGMP) are attenuated by cyclic AMP (cAMP) and this interaction is reduced in pacing-induced failure of hypertrophic hearts. 8-Bromo-cyclic-GMP (8Br) (2 μg/kg/min) was infused into the left anterior descending artery (LAD) in eight control, eight ventricular hypertrophy (LVH), and eight pacing-induced failure (failure) dogs. After return to baseline, isoproterenol (0.1 μg/kg/min) was infused, followed by 8Br. Regional myocardial work [force ∗ segment shortening], and O 2 consumption (VO 2 ) [coronary blood flow ∗ O 2 extraction] were measured. cGMP levels were determined by radioimmunoassay. 8Br decreased regional work from 3812 ± 839 g ∗ mm/min by 17% ( P = 0.05) and VO 2 by 29% ( P = 0.05) in control, but not in LVH (from 1073 ± 182 by −10%, VO 2 by −16%) or failure (from 495 ± 145 by −9%, VO 2 by 0%). Isoproterenol increased work by 43% and VO2 by 48% in controls ( P = 0.05) and in LVH (work by 54%, VO 2 by 39%; P = 0.05) but not in failure (work by −28%, VO 2 by −5%). Subsequently, 8Br had no effect on work or VO 2 in control (−2%, −13%), LVH (−12%, −30%), or failure (+13%, +14%). cAMP levels were elevated by isoproterenol in control (381 ± 115 pmol/g versus 553 ± 199 pmol/g) and LVH (313 ± 55 versus 486 ± 227; P = 0.05), but not in failure (300 ± 60 versus 284 ± 126). After isoproterenol, 8Br further elevated cAMP in control (687 ± 122; P = 0.05), but not in LVH or failure. In controls, cAMP attenuates cGMP’s negative functional and metabolic effects. This interaction is blunted in LVH and pacing-induced failure.