Soils of Moricsala, their formation conditions and properties

Maģistra darba literatūras apskata sadaļā ir apzināta platlapju mežu izplatība Latvijā un Moricsalā, kā arī augšņu veidošanās procesu ietekmējošie faktori mežu augsnēs. Darba mērķis ir raksturot Moricsalas mežu augsnes un to fizikāli ķīmiskās īpašības. Pētījuma ietvaros ar statistiskām metodēm ir noskaidrotas galvenās ķīmisko un fizikālo īpašību atšķirības starp Latvijas augšņu klasifikācijas un starptautiskās FAO WRB augšņu klasifikācijas augšņu pamatgrupām, meža tipiem un dominējošām sugām. Augstā meža augšņu daudzveidība Moricsalā liecina par augšņu veidošanās procesu (organisko vielu akumulācija, podzolēšanās, lesivēšanās un glejošanās) atšķirīgajām telpiskajām izpausmēm, ko nosaka augsnes cilmiezis un tā granulometriskais sastāvs, reljefs un gruntsūdens līmenis, kokaudze un tās sastāvs, un kādreizējā cilvēka saimnieciskā darbība un zemes izmantošanas veids.The study gives general review about broad-leaved forests distribution in Latvia and Moricsala, and information about influencing factors of soil formation processes in forest soils. The aim of master’s thesis is to characterize Moricsala’s forest soils, their physical and chemical characteristics and spatial pattern in forest stands. Stastistic analysis have been established to reveal main regularities in soil physical and chemical characteristics between Latvian soil classification and international FAO soil classificationsoil groups, forest types and dominant species. High diversity of Moricsala forest soils show that formation processes (organic matter accumulation, podzolization, lessivage and gleying) different spatial manifestations are determined by the soil parent material and granulometric composition, topography and groundwater level, composition of tree stand, and former human activities and land use

Organic carbon and total nitrogen stocks in soils of Moricsala strict nature reserve

Šajā pētījumā aplūkoti augsnes organiskajās vielās saistītie- organiskais ogleklis un kopējais slāpeklis dažādās meža augsnēs Moricsalā. Pētījumā dots vispārīgs Moricsalas raksturojums, apskatīti akumulāciju ietekmējošie faktori, savstarpējā korelācija un organiskā oglekļa, slāpekļa saturs nedzīvās zemsegas un trūdvielu akumulācijas horizontā atkarībā no augsnes tipa un kokaudzes sastāva. Secināts, ka nedzīvās zemsegas horizonta un minerālā horizonta (Ah) Corg un Nkop koncentrācija starp dažādu mežaudžu augsnēm ar atšķirīgu kokaudžu sastāvu būtiski neatšķiras. Moricsalas vidējā organiskā oglekļa saturs nedzīvas zemsegas horizontā 21 t/ha iekļaujas kopējā Latvijas meža augšņu nedzīvās zemsegas organiskā oglekļa rādītājā. Atslēgas vārdi: Moricsala, augsnes organiskais ogleklis, kopējais slāpeklis, meža augsnesIn this bachelor thesis are examined soil organic carbon and total nitrogen amount in Moricsala forest soils. The study gives general characterization about moricsala, discuss the accumulation influencing factors, cross-correlation and organic carbon, total nitrogen content in the litter and mineral humus accumulation horizon depending on soil type and stand composition It is concluded that litter and mineral horizon (Ah) organic carbon and total nitrogen concentrations between different forest soils with different composition of forest stands are not significantly different. Moricsala forest litter mean organic carbon stock is 21,5 t / ha, so Moricsala parts in the total Latvian forest soil litter organic carbon index. Keywords: Moricsala, organic carbon, total nitrogen, forest soil

Vegetation changes in boreo-nemoral forest stands depending on soil factors and past land-use during an 80-year period of no human impact

Information on the long-term changes in plant communities that occur without human interference is limited, due to insufficient studies where vegetation can be resurveyed. In 1912, a strict nature protection reserve, with non-intervention management, was established on Moricsala Island in Latvia, located in the boreo-nemoral forest zone. Prior to establishment of the nature reserve, part of the island area was used for agriculture. The island is now covered almost entirely by forest dominated by Quercus robur and Tilia cordata on sandy soils. Resurvey was conducted in 2011 in seventeen plots in which tree layers and the understory vegetation had been described in 1930. The plots were classified into two groups based on tree species composition in 1930, to determine changes in species composition. Differences in understory and tree canopy composition between these groups persisted over the period between the studies, in relation to soil factors and past stand history. Considerable turnover of species occurred, with decrease of species typical of open habitats and replacement by species typical of nemoral (temperate deciduous) forest plant communities. In the past, Quercus robur had likely established in open habitats created by agricultural land-use or past fire, but is presently not regenerating in the understorey.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author