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Lucian - Eugen Bolboacă, Viorel Pocora and Emanuel Ștefan Baltag

Abstract

Scops Owl (Otus scops) is a small sized owl that is a summer visitor and a breeding species in Romania. It underwent a moderate decline in Europe in the last decades, probably due to habitat loss. In Romania, it is a poorly studied species of birds. Breeding data were uncertain for Iași County. During 2010 and 2012, we identified a number of 26 Scops Owl territories. In each territory, we mapped the habitats on an area that followed a radius of 200 m from the observed bird. Thus, we identified a number of 15 habitats. From all 15 habitats mapped, the open pastures with isolated clumps of trees and bushes were best represented (15.53%) of the total habitat types of the study area. Also, in Iași County we observed a sinantropism of Scops Owl, due to the fact that 10 out of 26 territories (38.5%) are situated in anthropic habitat.

Open access

Horea Olosutean, Codruța Olosutean and Daniela Ilie

ABSTRACT

On a field trip to the Busurca Canal, near Sulina, in the Danube Delta, an apterous Gerris argentatus male was captured. It measured only 5.1 mm from the tip of the head to the end of the last abdominal segment, and was the smallest adult pond skater recorded in Europe. This specimen was also the first to be describe as an apterous form of G. argentatus, the species previously being known as either macropterous or micropterous. A large macropterous male, measuring 6.77 mm, was also collected in the same habitat, its size exceeding the known measurement for the species. Five G. argentatus females were taken from two sites on the Busurca Canal, each one measuring under the 7.5 mm length documented as a minimum for females of the species, with the smallest sample being only 6.59 mm in length.

Open access

Liviu Aurel Moscaliuc

Abstract

In the present article, three spider species are presented as new faunistic elements for Romania: Oecobius maculatus Simon, 1870, Agelena orientalis C. L. Koch, 1837 and Scotolathys simplex Simon, 1884. Out of the three, O. maculatus, by its presence, also raises the count of the spider families known to occur in this territory to 36. O. maculatus appears to be, in Romania, an anthropicdependent element. A. orientalis is a relatively widespread species, rather difficult to distinguish from its sibling species A. labyrinthica, and because of this frequently mislabeled in collections. S. simplex is a rarer Mediterranean element found in Dobruja, close to the Black Sea coast. A case is made in support of an updated Romanian spider checklist.

Open access

Ioana Constantinescu, Otilia Ivan, Adina Călugăr and Bálint Markó

Mite Fauna of Ant Nests - Comparative Study of Mite Fauna in the Argeş River Basin (South Romania)

This paper presents the results of a comparative study on the major groups of mites associated with ants in two different areas (hilly and mountain) of the Argeş basin. Mites from order Gamasida (Suborders Uropodina and Gamasina) and order Oribatida, and the ant fauna (Order Hymenoptera, family Formicidae) were investigated. Out of 31 mite species identified, Oplitis hutae is new to science (Constantinescu, in press), five are recorded for the first time in the Romanian fauna, and two for the second time. Also, one of the host ant species, Lasius sabularum is recorded for the second time in the Romanian myrmecofauna. In addition to the faunistic synopsis, a brief ecological and zoogeographical characterization is presented.

Open access

Māris Kļaviņš, Ilga Kokorīte, Valērijs Rodinovs and Maruta Jankevica

Abstract

Environmental pollution of lakes and rivers is considered as one of the most important environmental problems. Analysis of nutrient and trace element accumulation in sedimentary phases of lakes can reflect the overall regional pollution level, and the observed accumulation patterns of pollutants in sediment profiles can be used to reconstruct the history of anthropogenic impacts. As pollutants in sediments are associated with other substances, it is important not only to study total concentrations of pollutants, but also their speciation forms. The aim of this study was to describe phosphorus (including speciation forms) and trace element concentrations in sediment profiles of Lake Engure and to evaluate human impact on organic matter accumulation and properties in lake sediments. The concentrations of the studied elements in sediments of Lake Engure are at background levels, which is clearly evident when compared with metal concentrations in lake sediments in West European countries. The analysis of element concentration changes in sedimentary profiles provided information about trends in recent accumulation (within the last 100 years) and on the balance between natural and human-induced accumulation processes. Analysis of nutrient concentrations in sediments aided in identifying background values as targets for lake management activities.

Open access

Jolanta Latosińska and Jarosław Gawdzik

Abstract

Sewage sludge ashes from grate furnace and fluidized bed furnace were used in this research. This research was carried out to investigate the impact of combustion technology on sewage sludge speciation of heavy metals from sewage sludge ash. This was achieved by conducting a sequential chemical extraction procedure Community Bureau Reference (BCR). This study indicated that heavy metals in sewage sludge ash were dominant in immobile fractions. Moreover, it was stated that the combustion technology of sewage sludge did not have a significant influence on the mobility of heavy metals in ashes

Open access

Melania Stan

Abstract

The seven species of stag beetles of the Romanian fauna are present in the coleopteran collection of the Museum: Aesalus scarabaeoides scarabaeoides (Panzer), Ceruchus chrysomelinus (Hochenwarth), Sinodendron cylindricum (Linnaeus), Lucanus cervus cervus (Linnaeus), Platycerus caraboides caraboides (Linnaeus), Platycerus caprea (De Geer) and Dorcus parallelipipedus (Linnaeus). Information on the collecting data and distribution maps are given for each species. We present the male and female habitus for the two species of Platycerus.

Open access

Linda Ansone, Linda Eglite and Maris Klavins

Abstract

Arsenic contamination of waters is a global problem; therefore, new approaches for its removal are needed. Peat, peat modified with iron compounds, iron humates and polymeric cation exchangers modified with iron were prepared and tested for sorption of arsenic compounds in comparison with weakly basic anionites. The highest sorption capacity was observed when peat sorbents modified with iron compounds were used. Sorption of different arsenic speciation forms onto iron-modified peat sorbents was investigated as a function of pH and temperature. It was established that sorption capacity increases with a rise in temperature, and the calculation of sorption process thermodynamic parameters indicates the spontaneity of sorption process and its endothermic nature.

Open access

Andrew W. Knight, Eric S. Eitrheim, Andrew W. Nelson and Michael K. Schultz

Abstract

Reprocessing of spent nuclear fuel usually employs the solvent extraction technique to recover fissile material, isolate other valuable radionuclides, recover precious metals, and remove contaminants. Efficient recovery of these species from highly radioactive solutions requires a detailed understanding of reaction conditions and metal speciation that leads to their isolation in pure forms. Due to the complex nature of these systems, identification of ideal reaction conditions for the efficient extraction of specific metals can be challenging. Thus, the development of experimental approaches that have the potential to reduce the number of experiments required to identify ideal conditions are desirable. In this study, a full-factorial experimental design was used to identify the main effects and variable interactions of three chemical parameters on the extraction of protactinium (Pa). Specifically we investigated the main effects of the anion concentration (NO3 -, Cl-) extractant concentration, and solution acidity on the overall extraction of protactinium by 2,6-dimethyl-4-heptanol (diisobutylcarbinol; DIBC) from both HCl and HNO3 solutions. Our results indicate that in HCl, the extraction of protactinium was dominated by the solution acidity, while in nitric acid the extraction was strongly effected by the [DIBC]. Based on our results, a mathematical model was derived, that describes the relationship between concentrations of anions, extractant, and solution acidity and the expected values of Pa distribution coefficients in both HCl and HNO3. This study demonstrates the potential to predict the distribution coefficient values, based upon a mathematical model generated by a full-factorial experimental design.

Open access

Manuel Ortiz and Ignacio Winfield

Abstract

The description of a new species of amphipod crustacean (Gammaridea) of the genus Leucothoe found in a sponge, collected during the 3rd Joint Cuban-Spanish Expedition to the waters of Guanahacabibes Peninsula, at the Western Cuban Platform, in July 2008, is given. The main differences among L. luquei n. sp., and the other species known in the region, are also presented.