Using trace elements in otoliths to discriminate between wild and farmed European sea bass (<Emphasis Type="Italic">Dicentrarchus labrax</Emphasis> L.) and Gilthead sea bream (<Emphasis Type="Italic">Sparus aurata</Emphasis> L.)

Trace elements in otoliths of sea bass (Dicentrarchus labrax L.) and sea bream (Sparus aurata L.) from fish farms and coastal wild populations in the western Mediterranean Sea were analysed by inductively coupled plasma-mass spectrometry. Results showed that concentrations of Mg, K, and Mn differed significantly between wild and farmed sea bass, while concentrations of Mg, K, Mn, Fe, Zn, Sr, and Ba varied significantly between wild and farmed sea bream. Discriminate analysis and cross-validation classification showed that the trace element profile in otoliths can be used to separate farmed fish from wild stocks with high accuracy on both sea bass (individuals correctly classified: 90.7 %) and sea bream (individuals correctly classified: 96.6 %). Moreover, trace elements in otoliths resulted to be useful to discriminate among wild fish stocks within each species.     

Feasibility of open recirculating system in temperate climate – a case study

The increasing number of depleted, overexploited and recovering world marine stocks, together with increasing demand for fish and need for sustainable management of aquatic resources has led to a gradual shift to inland intensive aquaculture with water reuse. Intensive recirculating systems are becoming a rapidly developing sector of aquaculture, with the objectives to increase production and minimize environmental impact. However, transfer of technologies from original sites to locations of different climate is not always successful. The present study evaluates the use of an open recirculating system in a temperate climate. The 3‐year study showed successful production with better fish growth and feed utilization than in a flow‐through facility at the same site, but presented significant issues necessitating changes in technology as well as physical adaptations. A positive effect of the technology with respect to the environment is possible, but systems must be adapted to temperate climatic conditions.     

Deposition of sulphur and nitrogen compounds in Croatia

Since precipitation is an efficient scavenger of pollutants, concentrations of major ions in precipitation reflect changes in chemistry of the atmosphere and in the subsequent exposure of various ecosystems to deposition. The National Atmospheric Precipitation Chemistry programme was initiated in 1978 and operated by Meteorological and Hydrological Service of Croatia to provide needed information on geographical patterns and temporal trends in precipitation chemistry in Croatia. To accomplish this, a network of about 20 stations, settled in different geographical regions, operates on a daily basis for 15 years now. Some monitoring stations are site- and study- specific; others are included in long-term, regional, or European monitoring networks (EMEP, GAW, MEDPOL, GEMS). The purpose of this work was to summarise existing data from the whole network for the period 1981–1992 and to compare data from measurements with EMEP model calculations of acid deposition. Results presented here show that annual average concentration and deposition values at remote sites agree reasonably well compared to modelled ones.     

Historical evolution of permanent gullies in the Myjava Hill Land, Slovakia

The Myjava Hill Land is part of the area with the highest density of permanent gullies in Slovakia (up to 11 km km⁻²). Gullies are often 10–15 m deep, and occasionally extend >20 m. The pattern and density of gullies have been controlled primarily by the original land use from the pre-collectivization era. Old maps and historical sources indicate two to three periods of gully formation. The central part of the area, settled between the second half of the 16th and the beginning of the 19th centuries, was affected by gully formation in two periods, the first between the end of the 16th century and the 1730s and the second roughly between the 1780s and 1840s. Marginal parts of the study area to the west and south–west, which were settled earlier, may have been affected by disastrous gullying as early as the 14th century. Gullies were formed during periods of extensive forest clearance and expansion of farmland, but the triggering mechanism of gullying was extreme rainfalls during the Little Ice Age. However, periods of gully formation in the Myjava Hill Land were not fully synchronous with the well-known phases of gullying in other central European countries.     

Heavy Metal Content of Soils and Plum Orchards in an Uncontaminated Area

There are multiple stressors derived from urbanizations that result in frequent disturbances on streams and rivers reducing water quality and threatens aquatic biota. P-glycoprotein (P-gp)-mediated multixenobiotic resistance (MXR) is a defence mechanism analogous to multidrug resistance (MDR), which has been demonstrated in several aquatic organisms. This system protects cells against the entry and the accumulation of xenobiotics and has been proposed as a biomarker for pollution assessment. We conducted a study in a post-urban reach of Esquel stream (Chubut Province) downstream a wastewater treatment plant, in order to assess the presence and activity of MXR in five freshwater macroinvertebrate species (Helobdella michaelseni, Helobdella simplex, Patagoniobdella variabilis, Hyalella curvispina and Chironomus riparius). We measured the accumulation of the model P-gp substrate rhodamine B (RB) in organisms previously exposed to pollution. Our results described the activity of the MXR system in the three species of leeches suggesting their suitability as the in vivo biomonitoring. We also identified a dependence of the transporter activity with the development stage in H. simplex, highlighting the importance of using organisms of similar size classes since it may affect observed results. Finally, we concluded that benthic freshwater macroinvertebrates possess different species-specific levels of MXR activity possibly influencing their natural distribution as well as their survival.     

Biological control of green mould on <Emphasis Type="Italic">Agaricus bisporus</Emphasis> by a native <Emphasis Type="Italic">Bacillus subtilis</Emphasis> strain from mushroom compost

Fifty bacterial isolates obtained from compost were tested in vitro against the causal agents of green mould in Agaricus bisporus. Isolate B-38 which induced 48.08% in vitro growth inhibition of T. harzianum T54 and 52.25% of T. aggressivum f. europaeum T77 was identified as Bacillus subtilis, based on 16S rDNA sequence and used in mushroom growing room experiments. B. subtilis B-38 did not decrease mycelial growth rate of Agaricus bisporus A15 in mushroom compost in glass tubes. After applying prochloraz-manganese, B. subtilis B-38 and B. subtilis QST 713, no significant differences in BE values among treatments were found concerning both total yield and the weight of healthy mushrooms. Statistical analyses showed that only inoculation significantly influenced the healthy mushroom yield. In plots inoculated with T. harzianum T54 disease incidence was significantly lower after treatments with prochloraz-manganese (11.81%), B. subtilis QST 713 (12.26%) and B. subtilis B-38 (14.19%) compared to the control (28.16%), as well as in plots inoculated with T. aggressivum f. europaeum T77 11.88%, 12.2% and 15.03%, respectively, in comparison with the control (23.47%). Statistically significant differences were not found among the efficacy values of tested bio-fungicides based on B. subtilis and the commercial fungicide prochloraz-manganese suggesting the use of B. subtilis B-38 and B. subtilis QST 713 as good alternatives to chemical fungicides.