This study outlines research performed on experimental plots established in forest plantations and in natural black pine forests. The objective of the study was to determine the habitat factors that ...have the greatest impact on the growth and development of natural black pine forests and black pine forests plantations upon the return of climatozonal vegetation. Plots 625 m2 in size were selected and vegetation inventories made, and the structural elements of black pine plantations examined. Multivariate analysis found that elevation and slope were the two variables that had the highest positive correlation with the floristic composition of the vegetation. Furthermore, one of the goals was to determine the differences with regard to reforestation with black pine. The analysis of the isolated experimental plots showed a clear grouping of plots according to habitat factors. The differences in the synecological factors in the research area resulted in the presence of sub-Mediterranean, epi-Mediterranean and eu-Mediterranean elements within the black pine forest plantations. This also reduces the risk of the occurrence and development of large wildfires.
Background and purpose: Hyperosmotic solutions of calcium chloride and calcium bromide, extensively used in the oil industry, can be a source of aquatic pollution.Materials and methods: In the ...present study, we investigated whether the freshwater snail Planorbarius corneus L., previously chronically exposed to toxic concentrations of these chemicals, can recover fecundity and growth in clean water. We also examined if a higher tolerance could be induced in F1 offspring after parental and developmental chronic exposure to the chemicals.Results: The fitness-recovery study showed a high compensatory potential of the snails to recover fitness through increased reproduction and growth. In the tolerance study, we observed increased tolerance in F1 offspring in hyperosmotic solutions of calcium chloride. However, there was no significant improvement of reproduction performance in bromide-containing solutions.Conclusions: Increased tolerance was associated with a redirection of resources from growth to maintenance and survival.
Abstract
Anogramma leptophylla is one of the rarest fern species in Balkan Peninsula. In Croatia, several localities were noted prior to this study, when its presence was confirmed with a discovery ...of a small population on the island of Mljet (Southern Adriatic). This was, after almost 80 years, the first reliable finding of this species along Eastern Adriatic. The establishment of A. leptophylla on the western part of the island of Mljet may be attributable to certain favourable environmental conditions, but essentially to higher air and soil humidity. Its unusual bryophyte-like life strategy, with short-living annual sporophytes, facilitates its survival under Mediterranean climate, generally unfavourable for pteridophytes.
The removal of a single tree growing in an urban area or a patch of forest for development purposes is a practice that results from inappropriate economic approach to and unawareness of the value of ...natural capital and the services it provides. The paper analyses the benefits of the existence of urban trees and discusses valuation methods, emphasizing in particular the value of vegetation in the coastal area of the Republic of Croatia. Due to holistic focus of the topic, a qualitative research is applied based on observations, authors’ previous research, experiences, reports on current research and legislation. Several instruments for the preservation and maintenance of vegetation are proposed ranging from the measures by local self-governments, upgrading the system of fees for forest general benefit functions to proper implementation of non-financial reporting which should apply to all companies whose operations may have an impact on natural capital, regardless of their size and ownership structure. National legislation should meet more than a minimum compliance with EU directives and international efforts in standardizing non-financial reporting. Many companies undertake activities that may and do exert pressure on vegetation cover or natural capital, as do also the entities of public interest such as local and regional self-government units and the companies established by them, which should also become liable to non-financial reporting.
The aim of this paper is to assess the functional shifts of the herb layer in the submediterranean Ostrya carpinifolia coppiced forests (central Italy) along a coppicing rotation cycle. More ...specifically, the following questions were addressed: i) is there a pattern in functional trait composition of the herb layer along a regeneration chronosequence?; ii) which traits states differentiate each regeneration stage?; iii) are patterns of trait state variation related to the change of the environmental conditions? Species cover percentage was recorded in 54 plots (20 m × 20 m) with homogeneous ecological conditions. Relevés, ordered on the basis of the time since the last coppicing event and grouped into three age classes, were analysed with regard to trait variation, based on species absolute and relative abundance. Differences in light, temperature, soil moisture, and nutrients bioindicator values between consecutive regeneration stages were tested using the non-parametric Mann–Whitney U-test. Multi-response permutation procedures (MRPP) revealed statistically significant separation between young and intermediate-aged stands with regard to most traits. Indicator species analysis (ISA) highlighted indicator trait states, which were filtered, along the chronosequence, by changes in environmental conditions. Redundancy analysis (RDA) revealed that light intensity had the greatest effect on traits states variation from the first to the second regeneration stage, while variation from the second to the third age classes was affected by temperature. Young stands were differentiated by short cycle species with acquisitive strategies that only propagated by sexual reproduction, with light seeds, summer green and overwintering green leaves, and a long flowering duration. Intermediate-aged and mature stands were characterized by traits associated with early leaf and flower production, high persistence in time, and showing retentive strategies aimed at resource storage (e.g., geophytes, spring green leaves, rhizomes, and mesomorphic/hygromorphic leaves).
Geographic isolation, altitude, climate, landscape and habitat are significant predictors of butterfly diversity in mountain ecosystems. Their diversity and its dependence on altitude, aspect ...(compass bearing) and biogeographic characteristics of the butterflies were surveyed on the karst mountain Biokovo in southern Croatia. The results affirm that there is a high diversity of butterflies in the study area and the species composition and biogeographic elements are more dependent on altitude than aspect of the mountain. The present study indicates that climate, relief and habitat preferences strongly influence the biogeographic features of species and the relationship between species richness per site and altitude, aspect and the altitude-aspect interaction. PUBLICATION ABSTRACT
Concentrated CaCl2 and CaBr2 salt solutions of densities up to 2.3 kg L-1 are regularly used to control hydrostatic pressure in oil wells during special operations in the exploration and production ...of natural gas and crude oil. Various concentrations of high density salts are frequently left in mud pits near the drilling site as waste, polluting fresh and ground waters by spillage and drainage. The toxic effects of these salts have already been observed. This study investigated the effects of CaCl2 and CaBr2 on water flea Daphnia magna Straus in a 21-day reproduction test. The three tested concentrations of CaCl2 (240, 481, and 1925 mg L-1) caused a significant dose-response decrease of reproduction (p<0.001). With CaBr2 (533 and 1066 mg L-1), only aborted eggs were produced, demonstrating the embryotoxicity of the substance. The results suggest that high concentrations of the tested chemicals are harmful to Daphnia's reproduction and could reduce its abundance.
The vascular flora of Krka National Park recorded after its proclamation in 1985 is presented and analysed. In total, 1509 plant taxa within 582 genera and 132 families were recorded. The most ...represented families are Compositae, Poaceae and Fabaceae, while the dominant chorotypes are south-European and Eurasian. Life-form analysis demonstrated that vascular flora of NP Krka lies between the typical Mediterraneanand the central European spectrum, confirming the sub-Mediterranean phytogeographical position of this area. The analyses of medians of ecological indicator values for light, air temperature and soil moisture showed the domination of species typical for open, warm and dry habitats.
Prikazana je i analizirana vaskularna flora Nacionalnog parka Krka zabilježena nakon njegova osnivanja 1985. godine. Ukupno je zabilježeno 1509 svojti unutar 582 roda i 132 porodice. Najbrojnije porodice su Compositae, Poaceae i Fabaceae, a najčešći florni elementi južnoeuropski i auroazijski. Analizom spektra životnih oblika utvrđeno je da se flora NP Krka nalazi između tipično sredozemnog i srednjoeuropskog spektra što potvrđuje submediteranski fitogeografski položaj Parka. Analizom medijana ekološkihindikatorskih vrijednosti za svjetlo, temperaturu zraka i vlagu tla utvrđeno je da prevladaju vrste otvorenih, toplijih i sušnih staništa.
The paper investigates the ameliorative properties of pine cultures in their site conditions on the island of Rab. Pines, as allochthonous and pioneer species, were used to afforest degraded and ...devastated areas on the island because of their important role in the process of progressive vegetation succession. Twelve sample plots were established in the forest pine cultures. They encompassed various pine cultures (maritime pine, Aleppo pine and black pine) in diverse parent substrates (limestone, reddish-brown quartz sand, Flysch) and different soil types (eutric cambisol, cambisol on limestone, red soil and rendzina). To process the data, the following multivariate analyses were used: Two Way Indicator Species Analysis (TWINSPAN), Canonical Correspondence Analysis (CCA) and Indicator Species Analysis. The research results showed differences among the forest cultures of black pine, Aleppo pine and maritime pine. A relationship was found between the quantitative environmental variables (slope, pH, humus, the C/N ratio, age and the quantity of leaf litter) and the vegetation. As well as the relationship of the species towards qualitative variables (type of pine culture, parent substrate, soil type, exposition).
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