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Castel Guelfo di Bologna, Italy

Rosati M.,University of Parma | Cantonati M.,Limnology and Phycology Research Unit | Fenoglio S.,University of Piemonte Orientale | Segadelli S.,Geological | And 2 more authors.
Journal of Freshwater Ecology | Year: 2016

Sampling in springs has several technical problems due to their reduced dimensions and habitat heterogeneity. A standardized quantitative method for sampling crenic macroinvertebrates has never been proposed. The aim of this study was to compare different sampling methods and consider their environmental impacts. First, we present a review of sampling methods found in the literature and discuss their advantages and disadvantages with respect to selective collection of the target community and habitat disturbance. Altogether, 10 different methods have been reported, the use of nets being the most common protocol. Second, we report the results of macroinvertebrate samplings performed in three springs, each surveyed twice, using three different methods (multi-habitat proportional hand net, baited traps, and vegetation washing), in order to compare their effectiveness in collecting macroinvertebrates. Overall, 32 macroinvertebrate taxa, mostly identified at family level, were collected in the sampled springs. Significant differences in abundances were found using different methods, while results for community structure were comparable between the hand net sampling and the combined use of the other two methods, notwithstanding slight differences in the composition of Coleoptera and Diptera assemblages. The hand net, with a multi-habitat proportional approach, yielded more thorough results, making it suitable for biodiversity inventories but having some potentially negative effects on spring habitats. Traps and vegetation washing are also reliable methods with negligible impacts on spring ecosystems that can be conveniently used in ecological studies. © 2016 Taylor & Francis Source

Mastrocicco M.,University of Ferrara | Giambastiani B.M.S.,University of Ferrara | Severi P.,Geological | Colombani N.,University of Ferrara | Colombani N.,University of Bologna
Water Resources Management | Year: 2012

A detailed vertical characterization of a coastal aquifer was performed along a flow path to monitor the seawater intrusion. Physico-chemical logs were obtained by both open-borehole logging (OBL) and multilevel sampling technique (MLS) via straddle packers in piezometers penetrating the coastal aquifer of the Po River Delta, Italy. The open borehole logs led to a satisfactory reconstruction of the extent of the fresh-saltwater interface but provided a misleading characterization of the distribution of redox environments within the aquifer. On the contrary, good fits between sedimentological, stratigraphycal and physico-chemical data were obtained using the straddle packers devices. This study demonstrates that, within coastal shallow aquifers evenly recharged by irrigation canals, the simple and economical OBL technique can lead to misleading results when used to characterize density dependent groundwater stratification but is deemed adequate for preliminary assessments of the saltwater wedge location. © 2012 Springer Science+Business Media B.V. Source

Bonsignore F.,Regional Agency for Environmental Prevention in Emilia Romagna | Bitelli G.,University of Bologna | Chahoud A.,Regional Agency for Environmental Prevention in Emilia Romagna | Macini P.,University of Bologna | And 4 more authors.
IAHS-AISH Publication | Year: 2010

During the past several decades underground fluid withdrawals induced severe cases of land subsidence in Bologna, Italy. The area features middle Pleistocene to Holocene alluvial deposits more than 400 m thick. Here, levelling measurements revealed a subsidence rate of more than 11 cm/year from 1974 to 1981. Subsidence monitoring was carried out using a levelling network and, recently, an interferometric analysis. In 2005 two pipe extensometers were installed in the northern part of the area, anchored at 100 and 200 m depth, respectively. The regional subsidence rate is now reduced; however, the monitoring performed by means of the two extensometers shows that the subsidence rate is cyclical with seasonal peaks. Copyright © 2010 IAHS Press. Source

Amorosi A.,University of Bologna | Guermandi M.,Geological | Marchi N.,Geological | Sammartino I.,Geologic Consultant
Science of the Total Environment | Year: 2014

One of the major issues when assessing soil contamination by inorganic substances is reliable determination of natural metal concentrations. Through integrated sedimentological, pedological and geochemical analyses of 1414 (topsoil/subsoil) samples from 707 sampling stations in the southern Po Plain (Italy), we document that the natural distribution of five potentially toxic metals (Cr, Ni, Cu, Zn and Pb) can be spatially predicted as a function of threemajor factors: source-rock composition, grain size variability and degree of soil weathering. Thirteen genetic and functional soil units (GFUs), each reflecting a unique combination of these three variables, are fingerprinted by distinctive geochemical signatures. Where sediment is supplied by ultramafic (ophiolite-rich) sources, the natural contents of Cr and Ni in soils almost invariably exceed the Italian threshold limits designated for contaminated lands (150 mg/kg and 120 mg/kg, respectively), with median values around twice the maximumpermissible levels (345 mg/kg for Cr and 207 mg/kg for Ni in GFU B5). The original provenance signal is commonly confounded by soil texture, with general tendency toward higher metal concentrations in the finest-grained fractions. Once reliable natural metal concentrations in soils are established, the anthropogenic contribution can be promptly assessed by calculating metal enrichments in topsoil samples. The use of combined sedimentological and pedological criteria to fingerprint GFU geochemical composition is presented here as a new approach to enhance predictability of natural metal contents, with obvious positive feedbacks for legislative purposes and environmental protection. Particularly, natural metal concentrations inferred directly from a new type of pedogeochemical map, built according to the international guideline ISO 19258, are proposed as an efficient alternative to the pre-determined threshold values for soil contamination commonly established by the national regulations. © 2014 Elsevier B.V. Source

Amorosi A.,University of Bologna | Bruno L.,University of Bologna | Rossi V.,University of Bologna | Severi P.,Geological | Hajdas I.,ETH Zurich
Global and Planetary Change | Year: 2014

Paleosol stratigraphy, a technique commonly applied in basin-margin settings to depict cyclic alluvial architecture on time scales of 10-100. ky, can be consistent with regional accommodation trends at even higher temporal resolution (1-10. ky), having strong implications for the sequence stratigraphy of late Quaternary, non-marine deposits. Three closely-spaced late Pleistocene paleosols (P1-P3), dating back approximately to 42-39, 35-31, and 29-26. cal. kyr BP, respectively, form prominent stratigraphic markers across a lithologically homogeneous interfluve succession in the subsurface of Bologna, close to the Apenninic foothills. These paleosols are weakly developed (Inceptisols) and can be tracked continuously for 6. km across the triangle-shaped interchannel zone between two gravel/sand-filled channel systems (Reno and Savena rivers). In particular, the thickest paleosol (P3) is a distinctive stiff horizon that can be traced into laterally extensive, erosional-based fluvial bodies. We infer the correlation between (P3) soil development (and channel downcutting) and the final stage of the stepwise Late Pleistocene sea-level fall that culminated at the marine isotope stage 3/2 transition around 29. cal. kyr BP (low accommodation systems tract). A fourth laterally extensive Inceptisol, encompassing the Pleistocene-Holocene boundary (PH), represents the major phase of soil development since the Last Glacial Maximum and is inferred to be related to channel entrenchment at the onset of the Younger Dryas. With the exception of the Iron Age-Roman paleosol, which reflects a predominantly anthropogenic control, the Holocene paleosols are laterally discontinuous and invariably more immature (Entisols) than their Pleistocene counterparts. This trend of decreasing paleosol development (and correlatability) upsection is interpreted to reflect increasing (transgressive-equivalent) accommodation during sea-level rise, thus confirming the possible extension of models used to interpret the ancient rock record to short-term depositional cycles. © 2013 Elsevier B.V. Source

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