INDOOR AIR QUALITY AND THERMAL COMFORT EVALUATION IN LATVIAN DAYCARE CENTERS WITH CARBON DIOXIDE, TEMPERATURE AND HUMIDITY AS INDICATORS

ABSTRACT Latvian children under the age of 7 can spend up to 60 hours per week in daycare centers and therefore it is very important to establish a healthy and comfortable daycare environment that children will find pleasant and stimulating to stay in. This study investigates the indoor air quality and thermal comfort within six daycare centers (old, renovated and new-built

The Revival of Indonesian Skin Care Brands

Skincare business in Indonesia has been growing enormously in the last decade, with the coming of international brands and the struggling of local brands, to win the Indonesian customers. The aim of this research is to analyze the influence of country of origin to purchase decision through the brand image, and the impact of country of origin on customer satisfaction for local Indonesian skin care brands. As this research is using the quantitative approach, the data are collected by using questionnaires which are distributed to selected samples of 179 respondents. The respondents are chosen from the consumers of Indonesian brands of skin care products. The data are analyzed with SmartPLS software. The results show that the country of origin has a positive influence to purchase decision, the country of origin has a positive influence on brand image, brand image has a positive influence on purchase decision, and, finally, brand image has a positive influence on customer satisfaction on local Indonesian brands of skin care products

Role of humic substances in agriculture and variability of their content in freshwater lake sapropel

ArticleThe term ‘humic substances’ (HS) refers to a general category of naturally occurring, biogenic, heterogeneous organic substances. They create the most widespread natural organic matter found in sediments, soils and waters. Organic carbon in soil (up to 70%) and peat (up to 90%) usually occurs in the form of HS. HS influence the formation process of fossil fuels, as well as they are involved in the plant nutrition process, have an influence on availability and toxicity of metallic and other elements. Furthermore, HS play a significant role in the global carbon geochemical cycle. Properties and application efficiency of humus depend on the source of HS. Freshwater sapropel is a huge reservoir of HS with superior biological activity, although their total content is lower than in peat. The aim of this paper, firstly, was to present the information about the options of HS in agriculture and their main effects on plant growth. Secondly, determination and characterization of HS content in freshwater lake sapropel was performed as sapropel nowadays becomes a popular natural organic-mineral fertilizer and soil conditioner. Sapropel samples were derived from Lake Pilvelis, Lake Pilcines, Lake Vevers, Lake Liducis and Lake Padelis situated in Eastern Latvia. Investigation of HS content in sapropel is significant for the Baltic States and Northern Europe due to wide distribution and availability of sapropel in freshwater bodies. That promotes a search for new ways of extraction methods and bioeconomically effective utilization of this natural resource, obtainable in economically significant amounts, with high opportunities of its use especially in agriculture. Contemporary agriculture strongly desiderates in new products of high effectivity enhancing soil and crop productivity and quality hand in hand with sustainable development and careful attitude to the nature and surrounding environment, thus, one of the ways how it can be achieved is understanding how, where and how much HS preparations can be applied

The influence of surrounding vegetation and landscape patterns on distribution of forest fires ignated by grassland burning

Bakalaura darba mērķis ir noskaidrot kūldegu un to izraisīto meždegu izplatību Latvijā un to noteicošos ainavas un veģetācijas faktorus. Pētījumā analizēta kūlas dedzināšanas izraisīto mežu ugunsgrēku izplatība Latvijā 2010.–2015.g., 238 zināmajos gadījumos dešifrēta ainavas struktūra un biotopi, kā arī apsekoti pieci zālāji un ievākti 100 virszemes biomasas paraugi. Rezultāti liecina, ka kūlas dedzināšana ir nozīmīgs faktors mežu ugunsgrēku izplatībā, bet tiem nav ciešas saiknes ar vispārējo mežu ugunsgrēku izplatību. Kūldegu un to izraisīto meža ugunsgrēku izplatībā nozīmīgi ainavas faktori ir ceļi un ūdensobjekti, kas saistīts vietas pieejamību un cilvēku uzturēšanos. Kūldegas un to izraisītās meždegas galvenokārt izceļas atmatās, kur aug monodominantas graudzāļu audzes, jo īpaši slotiņu ciesas Calamagrostis epigeos audzes. Vidēji virszemes biomasa ir 483,8 g/m2.The aim of the Thesis was to reveal the influence of surrounding vegetation and landscape patterns on distribution of forest fires ignited by grassland burning. Author analysed distribution of forest fires ignited by grassland burning in Latvia. Remote sensing data were used to analyse landscape elements and vegetation types for 238 known cases. Aboveground biomass was sampled in 5 grasslands, and 100 samples of litter biomass were collected. The results showed that grassland burning is a notable factor ifluencing forest fire distribution, but with no relationship to overall distribution of forest fires. Road and water objects are notable landscape factors for grassland burning and their ignited forest fires. Grassland wildfires usually arise in abandoned grasslands that mostly consist of monodominant grass stands, especially wood Small-reed Calamagrostis epigeos. Mean aboveground biomass is 483,8 g/m2

Data for: Accumulation of metals and changes in the composition of freshwater lake organic sediments during the Holocene

Distribution of metals in freshwater sediment strata formed during the Holocene in the territory of Latvia has been studied rather insufficiently. Considering the large volume of accumulated organic matter in sediments, studies of the content of metal elements in sediments can help to determine the peculiarities of metal accumulation process in limnic systems and biogeochemical cycling of metals. Lake Pilvelis, located in the eastern part of Latvia (the northern part of Europe), was selected as the study site. Lake Pilvelis is a small lake of a glacial origin, and more than 90% of its depression is filled with organic-rich sediments, such as gyttja or freshwater sapropel, with an average thickness of 450 cm. Development stages of Lake Pilvelis since circa 10 000 cal BP are described in detail by means of reconstruction of the Holocene palaeoenvironmental conditions in the lake using multiproxy sedimentary records. This study represents analysis of the elemental composition and content of metallic elements in gyttja with the main target to characterise the accumulation rate of metals in a full profile of gyttja and to determine the anthropogenic impact depending on the evolution of the lake and genesis of sediment organic matter. Correlation among the components characterising such sediments as gyttja and metallic elements showed element distribution into three main groups according to the content of organic or mineral compounds. The principal component analysis revealed four main impact factors indicating the origin of metallic elements and the accumulation tendencies of metals in sediment layers