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In this paper, we present an approach to evaluate the hydrological alterations of a temporary river. In these rivers, it is expected that anthropogenic pressures largely modify low-flow components of the flow regime with consequences for aquatic habitat and diversity in invertebrate species. First, by using a simple hydrological index (IARI) river segments of the Celone stream (southern Italy) whose hydrological regime is significantly influenced by anthropogenic activities have been identified. Hydrological alteration has been further classified through the analysis of two metrics: the degree (Mf) and the predictability of dry flow conditions (Sd6). Measured streamflow data were used to calculate the metrics in present conditions (impacted). Given the lack of data from pristine conditions, simulated streamflow time series were used to calculate the metrics in reference conditions. The Soil and Water Assessment Tool (SWAT) model was used to estimate daily natural streamflow. Hydrological alterations associated with water abstractions, point discharges and the presence of a reservoir were assessed by comparing the metrics (Mf, Sd6) before and after the impacts. The results show that the hydrological regime of the river segment located in the upper part of the basin is slightly altered, while the regime of the river segment downstream of the reservoir is heavily altered. This approach is intended for use with ecological metrics in defining the water quality status and in planning streamflow management activities.

As most of the rural areas in Mediterranean Region, the Celone river basin (Apulia, Italy) is characterized by diffuse pollution from agriculture. Nutrient export from terrestrial ecosystem to the river is controlled by hydrological processes and nutrient input from point and non-point sources. In the present paper, anthropogenic nitrogen input and the riverine export of nitrate-N (N-NO) were quantified through several survey campaigns, continuous measures of streamflow and discrete determinations of concentrations. A different frequency for water sampling was used, respectively, during floods and during normal- or low-flow state. Nitrate-N concentrations in surface waters were found to vary considerably across the seasons. The riverine N-NO export was estimated to be about 14 kg N ha year. Major N inputs derived from fertilizers and animal manure correspond to 68.2 and 24 kg N ha year, respectively. Nitrate-N fluxes in stream during flood events (21 days) accounted for about 63% of the annual loading. This study clearly demonstrates the importance of flood event contributions to the annual nutrient loading delivered to the reservoir and that more efficient fertilizers and management practices are needed to reduce N input. [ABSTRACT FROM AUTHOR]

In this paper, the results obtained from multivariate statistical techniques such as PCA (Principal component analysis) and LDA (Linear discriminant analysis) applied to a wide soil data set are presented. The results have been compared with those obtained on a groundwater data set, whose samples were collected together with soil ones, within the project 'Improvement of the Regional Agro-meteorological Monitoring Network (2004-2007)'. LDA, applied to soil data, has allowed to distinguish the geographical origin of the sample from either one of the two macroaeras: Bari and Foggia provinces vs Brindisi, Lecce e Taranto provinces, with a percentage of correct prediction in cross validation of 87%. In the case of the groundwater data set, the best classification was obtained when the samples were grouped into three macroareas: Foggia province, Bari province and Brindisi, Lecce and Taranto provinces, by reaching a percentage of correct predictions in cross validation of 84%. The obtained information can be very useful in supporting soil and water resource management, such as the reduction of water consumption and the reduction of energy and chemical (nutrients and pesticides) inputs in agriculture. [ABSTRACT FROM AUTHOR]

The Celone River Basin (Puglia, Italy) is characterized by a diffuse pollution from agricultural sources. Like most intermittent rivers in the Mediterranean area, this stream is not well monitored; only few water quality data are available. Thus, due to high variability in streamflow and nutrient concentrations, which characterizes this type of rivers, it is difficult to estimate accurately nutrient loads from point and non point sources and consequently anthropogenic activities impact on the river. In this work, a detailed study was carried out on the Celone river to identify the chemical characteristics of the water and to quantify the annual nutrient loads delivered to the downstream reservoir. An automatic sampler and a flow module were set up in a section of the river. Continuous measures of flow were carried out using a different frequency for water sampling when floods occurred and during normal or low flow state. Nutrient concentrations in the water samples were accurately determined in laboratory. Water quality of the river was found to vary considerably along the year in terms of nutrient concentration. Nitrate and total phosphorus are the main cause of water pollution. Nutrient losses by surface runoff were essentially a winter process. The contribution per hectare of non point sources can be estimate at about 39 kg/ha of total nitrogen and 2.4 kg/ha of total phosphorus. Estimates of loads in terms of TN and TP for the 21-day period of flood were calculated in 55 and 81% of annual loads, respectively. This study clearly demonstrates the importance of flood event contribution to the annual nutrient load. [ABSTRACT FROM AUTHOR]

The objective of the present work is a spatial analysis aimed at supporting hydrological and water quality model applications in the Canale d'Aiedda basin (Puglia, Italy), a data-limited area. The basin is part of the sensitive environmental area of Taranto that requires remediation of the soil, subsoil, surface water, and groundwater. A monitoring plan was defined to record the streamflow and water quality parameters needed for calibrating and validating models, and a database archived in a GIS environment was built, which includes climatic data, soil hydraulic parameters, groundwater data, surface water quality parameters, point-source parameters, and information on agricultural practices. Based on a one-year monitoring of activities, the average annual loads of N-NO3 and P-PO4 delivered to the Mar Piccolo amounted to about 42 t year−1, and 2 t year−1, respectively. Knowledge uncertainty in monthly load estimation was found to be up to 25% for N-NO3 and 40% for P-PO4. The contributions of point sources in terms of N-NO3 and P-PO4 were estimated at 45% and 77%, respectively. This study defines a procedure for supporting modelling activities at the basin scale for data-limited regions. [ABSTRACT FROM AUTHOR]