Olgerts Nikodemus

Country-specific correlations across Europe between modelled atmospheric cadmium and lead deposition and concentrations in mosses

Previous analyses at the European scale have shown that cadmium and lead concentrations in mosses are primarily determined by the total deposition of these metals. Further analyses in the current study show that Spearman rank correlations between the concentration in mosses and the deposition modelled by the European Monitoring and Evaluation Programme (EMEP) are country and metal-specific. Significant positive correlations were found for about two thirds or more of the participating countries in 1990, 1995, 2000 and 2005 (except for Cd in 1990). Correlations were often not significant and sometimes negative in countries where mosses were only sampled in a relatively small number of EMEP grids. Correlations frequently improved when only data for EMEP grids with at least three moss sampling sites per grid were included. It was concluded that spatial patterns and temporal trends agree reasonably well between lead and cadmium concentrations in mosses and modelled atmospheric deposition.

The Monitoring and Risk Assessment of Zn Deposition Around a Metal Smelter in Latvia

Heavy metal concentrations in Hylocomium splendens collected around a metal smelter in Latvia showed very high concentrations of Zn (>200 μg/g), and elevated concentrations of Pb (38.3 μg/g) and Cu (18.3 μg/g). In an attempt to better evaluate the potential toxicity of the high Zn concentrations, a serial elution method was used to determine the concentrations of zinc in intercellular, extracellular exchangeable cell wall, intracellular, and particle fractions. The intercellular Zn concentrations represent the water soluble component of the total concentrations, and were low with no clear trends. Zn concentrations in the extra- and intracellular and particle fractions decreased exponentially from the pollutant source. Intracellular Zn concentrations in moss close to the emission source are within the range considered to be potentially toxic, from other single element exposure studies. The proportion of Zn in the relatively insoluble particle fraction, which is least associated with environmental risk, was greater closer to the pollution source, reaching > 30% in the oldest Hylocomium splendens segments.

Use of the O Horizon of Forest Soils in Monitoring Metal Deposition in Latvia

The concentrations of Cu, Cd, Pb, Zn, V,Ni, Cr, Fe Ca, Mg and K were determined in the organicsoil layer (O horizon) of pine forests in Latvia. Theconcentrations were expressed on a mass, volume andsurface area basis. When concentrations were calculatedper unit mass of the O horizon, significant positivecorrelations between concentrations in the O horizon andPleurozium schreberi were achieved for mostelements (excepting Cr, Ca and K), and to lesser degreesfor Cu, Pb, Zn, V, Ni and Fe when calculated on a volumeor area basis. Non-rotated principal components analysisidentified a major soil factor related to bulk density(volume- and area-based concentrations). The main groupsof related elements defined by varimax-rotated PCAcomponents were similar for the mass- and volume-baseddata, and regions with elevated levels of these elementscould be related to local pollution sources, similar tothe patterns previously reported from surveys based onmoss.

Influence of afforestation on soil genesis, morphology and properties in glacial till deposits

A study of soil morphological, physical and chemical properties was performed in woodland of different ages, in which spruce (Picea abies), aspen (Populus tremula) and birch (Betula pendula) growing stocks have colonized former agricultural land. The aim of the study was to clarify changes in soil genesis, morphology and properties due to the afforestation of abandoned agricultural land in glacial till deposits. The research showed that soil in these deposits (loamy sand, loam, clay) retains the morphological properties of agricultural land for up to 100 years. Secondary podzolization features in the soil profiles were observed within 100 years of the start of afforestation, whereas the diagnostic properties of Albic and Spodic horizons had not developed in the soil profile after 200 years. This study demonstrated that the morphological and physico-chemical properties of forest litter horizons, including the accumulation of organic substances, are dependent on forest age; however, changes in the properties of mineral soil horizons are mainly related to woodland age. Following the afforestation of agricultural lands, changes in soil pHKCl, organic matter content and extractable Al and Fe concentrations occur more rapidly than changes in soil diagnostic properties and profile formation.

Coherence between marine and land use planning: public attitudes to landscapes in the context of siting a wind park along the Latvian coast of the Baltic Sea

The aim of this paper is to contribute to coherence in marine, coastal and land use planning and management from the perspective of landscape values. At a time when new sea uses are emerging and marine spatial planning laws and regulations are being adopted, but have not yet been put into practice, research studies are required that provide spatial planners with informed insights concerning public stakeholder attitudes to controversial policies. The undertaken research explored the attitudes of two important social groups (local residents and tourists/recreational users) regarding locating wind parks in the marine and/or terrestrial environment along the Latvian coast of the Baltic Sea. The results of the study indicate that both groups support land-based wind park development versus offshore. Moreover, the visibility of wind turbines influences the willingness of tourists to visit recreation sites and impacts directly on their duration of stay. Research findings indicate that policy makers and spatial planners from both marine and land domains should adopt a broader and more integrated approach when setting priorities and allocating space for development activities where both domains are involved.

Element Inputs by Litterfall to the Soil in Pine Forest Ecosystems

Within the framework of the litterfall chemistry subprogram of the integrated monitoring program, litterfall was collected, and the concentrations of Ca, Mg, K, Pb, and Zn were measured during 1999–2003 at the Taurene and Rucava monitoring stations in Latvia. The results showed that at Rucava there was higher production of litterfall than at Taurene due to a higher tree density. The mean annual litterfall was 3630.42 kg/ha−1 in Rucava and 3022.11 kg/ha−1 in Taurene, with maximum production in autumn at both sites. The litterfall production among the catchments varied seasonally because length of growing period, composition of tree species, and density of snow cover. The higher Ca, Mg, and K concentrations in Taurene were due to greater birch litter contributions and soil chemical properties. The higher Pb and Zn concentrations in the Rucava IM catchment can be explained by the influence of long distance transboundary air pollution and local sources. The chemical element concentrations showed seasonal vari...

Past and Contemporary Changes in Forest Cover and Forest Continuity in Relation to Soils (Southern Latvia)

ABSTRACT: A set of medium-scale historical maps was used to reconstruct changes in spatial patterns of forest area during the last 220 years in an agricultural matrix of northeastern Europe (Zemgale region, Latvia). Changes in total forest area by soils were determined, as well as the time period of continuous forest cover. Proportion of protected area for each soil trophic group was also calculated. Patterns of recent forest development differed between soil trophic groups. Afforestation occurred mainly on wet and poor soils in the 19th and 20th centuries, while the proportion of woodland area on fertile soils typical for nemoral forests was fairly stable. Only 1% of the fertile soil area has been covered by continuous forest for more than 220 years, and only 11% of them are protected. Nemoral deciduous forests cover only 15% of their potential natural vegetation area of forested eutrophic soils. Therefore, in regard to habitat protection that is representative of natural distribution of ecosystems, priority in conservation should be given to forests on fertile soils.

Influence of De-Icing Salt on K Supply and Street Trees Ecological Status in Riga, Latvia

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 leaves and the extent of leaf necrosis, although unfavorable K/Na ratio has additive negative impact.

Landscape planning as an asset for regional development in Latvia

In Latvia sustainable development strategies of all five planning regions acknowledges landscape planning as an asset for regional sustainability. Moreover, there are now various frameworks that can promote landscape planning, the most important of them are the National Landscape Policy and the thematic plan framework. Therefore, landscape aspects in territorial planning from a mere landscape description as part of territorial characterization have shifted into more integrative and functional part of territorial planning process. Yet, landscape planning is still a marginal activity in Latvia. This paper aims to analyse and expand challenging issues around the elaboration of landscape plans as part of territorial planning processes in Latvia through legislative framework and planning analysis. We reviewed the three most recent landscape planning cases, discussing different planning situations in the context of European Landscape Convention and territorial planning in Latvia. Three planning situations are distinguished: landscape thematic plan as a policy and landscape assessment document, landscape thematic plan as an assessment and the recommendation document, and landscape assessment as part of territorial plan. All three approaches show integrity with territorial planning and reveal the benefits for sustainable territorial planning and regional development, however they still lack the locals’ participation aspects, as well as the focus on ordinary landscapes, social capital and land economics.