0000000000975548
AUTHOR
Anita Osvalde
showing 13 related works from this author
Dianthus superbus as a critically endangered species in Latvia: evaluation of its growth conditions and conservation possibilities
2021
Abstract Dianthus superbus is one of the most endangered species in Latvia and is on the verge of local extinction. Therefore, the aim of this study was to inventory previously identified populations of D. superbus in Latvia and to develop activities to conserve this species in accordance with the results obtained in situ. Expeditions on 18 previously documented locations, according to the data of Nature Conservation Agency, revealed only three existing D. superbus localities in Latvia with a significant number of specimens located in the Latgale region near Silenieki. In 2020, for the first time, two more new D. superbus localities were found in the vicinity of these three approved locatio…
Influence of De-Icing Salt on K Supply and Street Trees Ecological Status in Riga, Latvia
2009
The study was conducted to evaluate the toxic effect of soil and plant pollution with Na and Cl− on K supply and ecological condition of the street trees (Tilia × vulgaris H.) in Riga during 2005 and 2007. The results revealed that the ecological status of street trees could be characterized as seriously injured due to high concentrations of Na and Cl− in soil (maxNa 1,568.1 mg/kg; maxCl 744.9 mg/kg) and lime leaves (maxNa 1.93%; maxCl 3.00%). The concentrations of Na and Cl− in lime leaves demonstrated a marked tendency to increase during summer, while the concentrations of K in leaves decreased (min. 0.15%). There were close correlations between the concentration of Na and Cl− in lime lea…
Chemical Composition of Scots Pine Bark as a Bioindicator of Environmental Quality in Riga, Latvia / Priežu Mizu ķīmiskais Sastāvs Kā Vides Stāvokļa …
2015
Abstract The chemical composition of pine bark was used for the determination of environmental quality in Rīga. Bark samples were collected at 54 sites in Rīga differing in vegetation and building area characteristics (urban forests, parks and cemeteries, dwelling houses, and streets and railway zones) and at 52 sites from rural areas in Latvia (background level). Concentrations of Ca, Mg, Na, K, Fe, Mn, Zn, Ni, Cu, Cd, Pb, and pH was determined in the samples. The results showed significantly higher concentrations of chemical elements in pine bark collected in Rīga, compared to background levels: Fe and Cu concentrations three times higher, and other elements - up to 1.8 times. The highest…
Physiological Responses of Wetland Species Rumex Hydrolapathum to Increased Concentration of Biogenous Heavy Metals Zn and Mn in Substrate
2020
Abstract The aim of the present study was to determine if individuals of Rumex hydrolapathum Huds native to saline wetlands are able to tolerate high concentration of biogenous heavy metals Zn and Mn in substrate and to accumulate high concentration of these metals in aboveground parts. Plant physiological status was monitored by using non-destructive analysis of chlorophyll and chlorophyll a fluorescence. R. hydrolapathum plants accumulated up to 1840 mg·kg−1 Zn and 6400 mg·kg−1 Mn in older leaves. The usefulness of monitoring changes in chlorophyll concentration and chlorophyll a fluorescence parameters to predict physiological response of R. hydrolapathum plants to excess Zn and Mn was n…
Toxic impact of the de-icing material to street greenery in Riga, Latvia
2008
Abstract There is little information on the ecological composition of snow on roads as well as the toxic effect of de-icing salt on the ecological status of the street trees ( Tilia x vulgaris H.) in Latvia. Tilia x vulgaris is one of the most widespread tree species of street greenery in the boreo-nemoral zone – in Central, Northern and Eastern Europe. This investigation was done to find out the accumulation of de-icing salt (main elements – sodium and chlorine) in the snow–soil–plant system of street greenery in the central part of Riga (2004–2005), in order to reveal the toxic effect on the ecological status of the street trees ( Tilia x vulgaris ). Snow, soil and leaf samples were colle…
Comparative Chemical Characterisation of Soils at Cypripedium Calceolus Sites in Latvia
2017
Abstract The main aim of the study was to evaluate the soil chemical characteristics of Cypripedium calceolus sites in Latvia for understanding of the species ecology, and its conservation problems and possibilities. Soil for 27 C. calceolus sites in Latvia was analysed during 2007-2015. The concentration of plant available essential nutrients (N, P, K, Ca, Mg, S, Fe, Mn, Zn, Cu, Mo, B), soil pH, electrical conductivity and concentration of organic matter were determined. Nutrient concentration of C. calceolus leaf samples from six sites were determined. The results demonstrated high heterogeneity in soil chemical composition with high variation for Ca, Mg, and Mn. The results suggest some …
DYNAMICS OF SOIL NUTRIENT STATUS OF HIGHBUSH BLUEBERRY IN LATVIA, 2006-2017
2019
In Latvia, the first commercial highbush blueberry (Vaccinium corymbosum L.) plantings have been established on a few hectares at the end of the 1990th. Since then, a remarkable growth has noticed and today the total cultivated area reaches 280 hectares. An increasing market demand for fresh and processed berries provides a future upward trend in the development of blueberry crop in Latvia. In general, blueberry is a highly specialized crop that has definite soil agrochemical and climatic requirements. There are two main soil types used for blueberry cultivation in Latvia: well-drained acid sandy soils with high organic matter content and sphagnum peat soils. Evaluation and management of pl…
Vermicompost from municipal sewage sludge affects growth and mineral nutrition of winter rye (Secale cereale) plants
2015
ABSTRACTThe aim of the study was to investigate sewage sludge vermicompost application effects on growth and mineral nutrition of winter rye (Secale cereale L.) plants as compared to two initial levels of mineral nutrient availability, pure sand and sand enriched with inorganic nutrients at the optimal level. Addition of sewage sludge vermicompost significantly inhibited rye seed germination at 20 to 50% sand substitution independently on mineral nutrient supplement. Growth inhibition was evident at early stages of plant development. However, at the later stages, sewage sludge vermicompost acted both as mineral fertilizer and plant growth-promoting agent. Significant stimulation of mineral …
Wild Plants from Coastal Habitats as a Potential Resource for Soil Remediation
2020
The aim of the present review is to stimulate an interest in experimental exploration of native coastal plants as a valuable resource for development of and use in environmental remediation technologies. An attempt is made to analyze wild plant species from different coastal habitats in respect to the functional properties useful for soil remediation purposes. Several plant species from a number of coastal plant genera are described as potential models for further studies aimed at practical environmental phytoremediation, including Armeria maritima, Rumex hydrolapathum, Ranunculus sceleratus, Anthyllis maritima, Alyssum montanum subsp. gmelinii, and Sedum maximum. It is concluded that a lar…
A study of chemical characteristics of soil in relation to street trees status in Riga (Latvia)
2013
Abstract The chemical composition of soil and appropriate supply of nutrients are very important factors for normal plant growth and development. Lime tree ( Tilia x vulgaris H.), is a popular tree species used for urban landscaping in Europe. However, there is little information on the chemical element concentrations available to and recommended for T. x vulgaris in urban soils. The objectives of this study were: (1) to investigate the amount of nutrients, de-icing salts and heavy metals available for uptake by trees in the city centre on a seasonal scale; and (2) to assess the relationship between the vitality of T. x vulgaris and soil chemistry. The research was carried out in five stree…
ASSESSMENT OF THE IMPACT OF VERMICOMPOST AND PEAT EXTRACTS ON NUTRIENT ACCUMULATION IN TUBERS AND POTATO YIELD
2018
Investigations on the potential beneficial effect of humic substances on crop plant cultivation under extremely diverse soil and climatic conditions is of global character, thereby knowledge obtained on the basis of local investigations are of great importance world-wide. The aim of the research was to evaluate the effect of different application methods (seed tuber treatment and foliar application) of commercially-produced peat and vermicompost extracts on nutrient uptake in tubers and yield of potato ( Solanum tuberosum L.) using field experiments in organic farming system with potato variety ‘Borodjanskij Rozovij’. The tested extracts from the organic products included: peat extract (K45…
Salt accumulation and effects within foliage of Tilia × vulgaris trees from the street greenery of Riga, Latvia
2020
International audience; Green infrastructures within sprawling cities provide essential ecosystem services, increasingly undermined by environmental stress. The main objective in this study was to relate the allocation patterns of NaCl contaminants to injury within foliage of lime trees mechanistically and distinguish between the effects of salt and other environmental stressors. Using field material representative of salt contamination levels in the street greenery of Riga, Latvia, the contribution of salt contaminants to structural and ultrastructural injury was analyzed, combining different microscopy techniques. On severely salt-polluted and dystrophic soils, the foliage of street lime …
Smagie metāli - Pb, Hg, Ni, V, Sn, bioloģiskos objektos Latvijā un to toksiskuma mazināšana, regulējot augu barošanos
1996
Contributor other: Latvijas Zinātņu akadēmijas Bioloģijas institūts