Search results for "taiga"

Snowpack concentrations and estimated fluxes of volatile organic compounds in a boreal forest

2012

Abstract. Soil provides an important source of volatile organic compounds (VOCs) to atmosphere, but in boreal forests these fluxes and their seasonal variations have not been characterized in detail. Especially wintertime fluxes are almost completely unstudied. In this study, we measured the VOC concentrations inside the snowpack in a boreal Scots pine (Pinus sylvestris L.) forest in southern Finland, using adsorbent tubes and air samplers installed permanently in the snow profile. Based on the VOC concentrations at three heights inside the snowpack, we estimated the fluxes of these gases. We measured 20 VOCs from the snowpack, monoterpenes being the most abundant group with concentrations …

Trīsgadīgu bērnu vārdu krājuma pilnveides iespējas dabas vērojumu procesā

2018

Bakalaura darba temats: Trīsgadīgu bērnu vārdu krājuma pilnveides iespējas dabas vērojuma procesā. Bakalaura darba autors: Kristīne Greļa Pētījuma mērķis: Teorētiski analizēt un pētīt 3 gadīgu bērnu vārdu krājuma pilnveides iespējas dabas pastaigu procesā. Darbs sastāv no divām daļām: 1.Darba pirmajā daļā tiek analizēta zinātniskā literatūra par valodas fenomenu. Kā valoda tiek traktēta no psiholoģijas, pedagoģijas un valodniecības skatu punktiem. Būtisks uzsvars tiek likts uz valodas nozīmi bērna attīstībā, svarīgākie valodas attīstības un pilnveides vecumposmi. Bērnu vārdu krājums ir atkarīgs no apkārtējās vides, gan mikro, gan makro vidē. 2.Otrajā daļā tiek izklāstītas pētījuma metožu iz…

Pareizas stājas stiprināšanas iespējas pastaigas laikā 3 - 4 gadus veciem bērniem

2021

Kvalifikācijas darba tēma: Pareizas stājas stiprināšanas iespējas pastaigas laikā 3-4 gadus veciem bērniem. Darba teorētiskajā daļā analizēta literatūra par fizisko aktivitāšu nozīmi bērnu attīstības procesā un pastaigu organizēšanas raksturojumu pirmsskolā. Izvērtēti 3-4 gadus vecu bērnu pareizas stājas kritēriji, lai skolotājs var kvalitatīvāk organizēt bērnu pastaigas. Par teorētisko atziņu bāzi kalpoja tādu zinātnieku pētījumi kā R. Karlovska (2003, 2010), M. Kļujevs, J. Kocs (1997), V. Golubina (2007), K. Hustyi, M. Normand, T. Larson, & A. Morley (2012). L. Saveļjeva (2015) u.c. Empīriskajā pētījuma daļā tika novērtēti bērni 3-4 gadus vecumā pēc noteiktiem kritērijiem, pastaigu laikā …

The relationship between stocking eggs in boreal spawning rivers and the abundance of brown trout parr

2015

Abstract Stocking with eggs has been widely used as a management measure to support degraded salmonid stocks. In Finland, Atlantic salmon and both sea-migrating and lake-migrating brown trout are stocked as eggs, alevins, fry, parr, and smolt, whereas trout are also stocked as mature fish. The aim of this stocking is to improve catches and to support collapsed spawning stocks. We assessed the success of stocking with brown trout eggs in a study of 17 Finnish boreal forest rivers, of which 9 were subject to egg stocking. All rivers contained some naturally spawning trout. In 16 rivers, including non-stocking years and unstocked rivers, egg stocking did not increase the total (wild and stocke…

Pastaigas ar suni pilsētā: vienošanās par telpu un sociālā mijiedarbība

2021

Bakalaura darba "Pastaigas ar suni pilsētā: vienošanās par telpu un sociālā mijiedarbība" mērķis ir izpētīt desmit cilvēku, kuri ikdienā pastaigājas ar saviem suņiem Rīgas centrālajā daļā, neformālo praksi. Šīs tēmas nozīmīgums ir divējāds. Viens no iemesliem ir suņu adopcijas un iegādes pieaugums pandēmijas laikā, kas tiešā veidā attiecas uz vienošanās par telpu biežumu un intensitāti. Un otrs attiecas uz noteikumiem, kas ir spēkā, lai pārraudzītu šo praksi un to, kā tā īstenojas realitātē. Šī darba mērķis ir saprast, kā notiek tas, ka cilvēkiem, kuri pastaigājas ar suņiem, ir pastāvīgi jāvienojas par telpu, kā izskatās šīs telpas koplietošanas tikšanās un kā šī mijiedarbības prakse veido …

The effects of forest management on wood-inhabiting fungi occupying dead wood of different diameter fractions

2014

Forest management has caused severe ecological degradation throughout the Globe. One of its most prominent consequences is the drastic change in dead wood profile and consequently in the dead wood dependent biota. Wood-inhabiting fungi are, considering ecosystem functions, the most important species group utilizing dead wood, because they take care of majority of the decaying process. The earlier research focusing on the effects of forest management on wood-inhabiting fungi has strongly focused on large dead wood pieces (i.e. coarse woody debris, CWD), even though it has been shown that a major part of fungal diversity utilizes (also) small dead wood pieces (i.e. [very] fine woody debris, […

Biogenic and biomass burning organic aerosol in a boreal forest at Hyytiälä, Finland, during HUMPPA-COPEC 2010

2013

Abstract. Submicron aerosol particles were collected during July and August 2010 in Hyytiälä, Finland, to determine the composition and sources of aerosol at that boreal forest site. Submicron particles were collected on Teflon filters and analyzed by Fourier transform infrared (FTIR) spectroscopy for organic functional groups (OFGs). Positive matrix factorization (PMF) was applied to aerosol mass spectrometry (AMS) measurements and FTIR spectra to identify summertime sources of submicron aerosol mass at the sampling site. The two largest sources of organic mass (OM) in particles identified at Hyytiälä were (1) biogenic aerosol from surrounding local forest and (2) biomass burning aerosol, …

2011

Abstract. This paper describes the background, instrumentation, goals, and the regional influences on the HUMPPA-COPEC intensive field measurement campaign, conducted at the Boreal forest research station SMEAR II (Station for Measuring Ecosystem-Atmosphere Relation) in Hyytiälä, Finland from 12 July–12 August 2010. The prevailing meteorological conditions during the campaign are examined and contrasted with those of the past six years. Back trajectory analyses show that meteorological conditions at the site in 2010 were characterized by a higher proportion of southerly flow than in the other years studied. As a result the summer of 2010 was anomalously warm and high in ozone making the cam…

2012

Abstract. Ambient total OH reactivity was measured at the Finnish boreal forest station SMEAR II in Hyytiälä (Latitude 61°51' N; Longitude 24°17' E) in July and August 2010 using the Comparative Reactivity Method (CRM). The CRM – total OH reactivity method – is a direct, in-situ determination of the total loss rate of hydroxyl radicals (OH) caused by all reactive species in air. During the intensive field campaign HUMPPA-COPEC 2010 (Hyytiälä United Measurements of Photochemistry and Particles in Air – Comprehensive Organic Precursor Emission and Concentration study) the total OH reactivity was monitored both inside (18 m) and directly above the forest canopy (24 m) for the first time. The c…

Effects of forest restoration treatments on the abundance of bark beetles in Norway spruce forests of southern Finland

2009

Abstract Restoration of protected areas in boreal forests frequently includes creating substantial volumes of dead wood. While this benefits a wide range of dead wood dependent invertebrate species, some of these are regarded as forest pests. Therefore, the risk of elevated levels of tree mortality in surrounding commercial forests must be considered. In a large-scale field experiment in southern Finland, we studied the effects of restoration treatments on the abundance of bark beetles within and in the vicinity of restored areas, in particular focusing on Ips typographus and Pityogenes chalcographus . The treatments applied to managed Norway spruce forests were controlled burning and parti…