This thesis is part of Project of the Grant Agency of the Czech Republic No P504/11/1151, focused on the role of plants in the balance of carbon dioxide and the other greenhouse gases produced in the ecosystem of a sedge fen, which is situated on the study site Wet Meadows near Třeboň. The thesis deals with the growth dynamics of the dominant sedge, Carex acuta. The samples were taken using the method of successive harvests near the automatic meteorological station of Czech Globe, Academy of Sciences of the Czech Republic. During the growing season nine harvests were accomplished on 25.3, 15.4, 6.5, 5.6., 9.7., 5.8., 9.9., 21.10., 25.11.. On each date eight replicates were taken, i.e., a total of 72 samples within the vegetation season. The seasonal dynamic of the above ground biomass was compared between C. acuta and the other plant species on the experimental area. Both live and dead biomass, was harvested and subsequently sorted to single botanic species, dried, weighed and the values were processed using the MS Excel tables. The seasonal maximum of aboveground biomass of all plant species (both live and dead parts) was found on 9.7. (1452,72 g.m-2). Among plant species the highest values of aboveground biomass were attained by Calamagrostis canescens (1257,93 g.m-2) and C. acuta (1163,49 g.m-2). C. acuta displayed the highest density of all shoots on 15.4 (300 m-2),and the highest average weight of one shoot. The maximum length of the longest live shoot of Carex acuta was very consistent among the measurememnts.

This thesis offers the first detailed palaeoenvironmental analysis of wetland areas within sub-Arctic enclosed homefield’s. Significance of meadows were previously mentioned only briefly in the literature, suggesting influences in settlement site selection as well as importance in quality fodder production, producing up to two thirds of total hay resources in a somewhat marginal agricultural landscape. Given the importance of hay resources in Iceland it seems unusual these areas have received so little attention to date, despite extensive research on all other aspects of the Norse farm system. The organic sediments within the meadows, given their development in-situ over extended time periods, have the ability to record aspects of the intimate relationship between societal and environmental change, and so in a robust and holistic way our methods set integrates radiocarbon measurement, tephrochronology, palynology and thin section micromorphology from the same core; reflecting these findings against existing paleoclimate and archaeological site data. This combined application of the core techniques – palynology and soil micromorphology, has proven successful in creating effective human ecodynamic records from each of the study farms. Records obtained from the three farm sites in northwest and northern Iceland exposed the varying importance and differing utilisation of these wetland areas. Meadows would appear to have played an import role in choice of settlement site across northern Iceland, through the provision of open areas, and additional and immediately available fodder resources at settlement, in a landscape dominated by dense scrub. Meadows were found to have been in continuous use, albeit at varying levels of intensity, from settlement to the present day. In this respect the semi-natural resources are found to be remarkably resilient, demonstrating little alterations to their composition following severe climatic downturns, including that of the Little Ice Age, and volcanic eruption. Acting as a robust resource and safety buffer for settlements, contributing to fodder resources where reliability of other resources is jeopardised by environmental conditions. Research in the more marginal northwest peninsula provides the first evidence of artificially created wet meadows in Iceland, developed to give sustained fodder production for over-wintering livestock in an environment that inherently had a short growing season and lacked soil fertility. A further example of the nuanced land management practices adopted in the agriculturally fragile farmscapes of the Norse North Atlantic. The findings of the thesis have wider implications for understanding the emergence of resilient and sustainable communities in agriculturally marginal environments; to this end there remains many opportunities to use palaeoenvironmental research to study ecosystem responses to natural and anthropogenic stresses, giving us a better understanding of capacities to withstand future stresses.