The environment relating to the history of civilization is the notion, which more and more is used when thinking about the changes occurring in Latvian culture. In this research are considered all Latvian palace and manor parks and classified as an integral part of the heritage. The research was done from the year of 2009 to 2010. Fundamental principles the quality of today’s parks were taken, first of all, evaluating the cartographical and historical materials and available literature sources, secondly, chosen, mostly historically rich and varied parks, evaluating basing on landscape evaluation criteria, and, thirdly, summarizing the qualified parks, for working out qualitative and sustainable park development models in the future researches. Working out the evaluation system and principles of historic parks, it is possible not only to reanimate the historical landscape, but also get back the total landscape atmosphere, in spite of the loss of the main ensembles or their partly ruination. The park qualification, structure investigation, landscape inventory and analysis, as well as European experience in historic landscape maintaining and development, according to a similar landscape structure, which nowadays successfully functions as a heritage, is the base for an optimal and sustainable culture landscape development. The worked out order helps in understanding and analyzing the meaning of the historic park and its successful development tendency, in which are marked out the most important heritage objects in the particular landscape and they are reverted in a vital pulse and social processes.

An important factor in the development of forest ecosystem is the ability to regenerate. Natural intensity of self thinning of a forest depends on the tree species and environmental conditions. Due to abiotic and biotic factors in a continuous forest tract, there appears a clearing, which, depending on the size, forms new growth conditions. Over time, the resulting new space is occupied by herbaceous and woody vegetation. Most often regeneration of a new forest depends on the size of the plot. The study was conducted in 2013 during the growing season in a typical broadleaf forest stand. During the study woody vegetation and projection coverage of herbaceous vegetation was registered in large clearings. Light conditions in the plots and under tree canopies, as well as soil parameters were ascertained. Based on the collected data, the view of the structure of woody vegetation, projection coverage of herbaceous vegetation, light conditions, temperature, soil moisture content and pH changes were obtained. In order to clarify the influence of microclimatic conditions on natural forest regeneration, the data on light and soil characteristics were analyzed. The aim of the study - was to determine the changes of woody and herbaceous vegetation in spruce stand clearings and to assess the impact of microclimate. During the study it was found out that in large plots dominated species demanding higher amount of light, while herbaceous vegetation was attributed to the third, fourth groups of aggressiveness. Naturally regenerated seedlings condition was mostly influenced by light conditions and soil moisture content.

Ecological farming is relevant to protected areas. The aim of the study is to perform an analysis of farms applying organic farming measures as well as the analysis of the change of their areas in Aukštadvaris and Krekenava regional parks (RP). The object of the investigation - the farms of Aukštadvaris and Krekenava regional parks. The study is carried out to determine how many farms, forming the regional parks‘ territory, are managed according to the principles of organic farming. The change of the above- mentioned farming area for 2009-2011 is analyzed as well. Paluknys and Naujamiestis subdistricts, not incorporated into the territory of regional parks, were chosen for the comparison analysis. The analysis of the 2009 – 2011 period showed that the declared areas in Krekenava RP have decreased, and the area of farms applying organic measures has increased by 81.69 hectares (nearly 2.5 times). The number of organic farms increased by 1.5 times in Aukštadvaris RP over the period of 2009-2011, and the area has increased by 187.36 ha. The percentage calculations revealed that in 2011 the area of farms applying organic farming measures in Aukštadvaris RP made up 18.89 per cent of the total area declared, the number of farms - 6.61 per cent. The area of farms applying organic farming measures in Krekenava RP was only 1.71 per cent, measures were applied only by 1.89 per cent of all the declared.

The research was accomplished within the framework of the doctoral thesis, with the aim to clarify the role of Latvian Manor Park in the settlement landscape ecology. Significance of the Latvian Historical Park in the settlement landscape ecological processes in Kuldiga district was discussed and analyzed. To achieve set objective of the research, there was developed the landscape ecology assessment methodology of the settlements in the influence of the historical parks based on generalized scientific cognitions and researches in the landscape ecology, and scientific researches of the population loads and historical park value. The developed method was applied by surveying the selected historical parks in the settlement, and by assessing biodiversity factors, urbanization load, and landscape ecological networking compatibility degree. As a result, the selected settlements of historical parks were marked in the district of Kuldiga in the landscape ecological map, highlighting the importance of both national and European level. The results indicate significance of the historical parks in the settlement landscape ecology and that the role of historical parks in the settlement landscape ecology is essential, which ensures the natural basic resources air, water and soil quality. In the settlements, the historical parks existence is high value and quality environmental guarantee, which would have been managed according to the proposed principles of landscape ecology science.

The study focuses on protected landscape aesthetic quality assessment where the main problem is how to associate aesthetical and ecological approaches. High ecological quality does not often correlate with high landscape aesthetic quality, and this relationship may differ depending on specific ecosystem. The landscape aesthetic quality assessment historically developed on two approaches. One of them - expert approach, which has dominated in landscape planning and management practice, and the second - perception approach, which has dominated in research. In protected landscape aesthetic quality assessment traditional approaches will be revised by ecology and green philosophy aspects. The study example regards important natural and protected areas around river Lielupe - from Jelgava city to Kalnciems. This is the landscape with high heritage, natural, biological values and it is also living, recreation place for people. Therefore, cooperation between aesthetic and ecological approaches in landscape assessment is needed. The outdoor investigations were carried out in autumn 2006. There were photographs and video materials on the first stage of investigation. In the second part aesthetic quality of views was analyzed with expert approach. There were three main groups of evaluation criteria of protected landscape aesthetic quality. These covered design and compositional outlines - features, their quality and relationship among these features. The results showed that not all criteria are suitable and effective for evaluation of protected landscape aesthetic quality because of restriction of specific ecological conditions.

Fire has been a part of natural disturbance regime in boreal and to some extent also hemiboreal forests, affecting soil and light conditions, seedbanks, trees and ground vegetation. The most significant factors affecting occurrence, severity and size of forest fires are anthropogenic, weather and the environment, all of which are changing due to human-caused climate change. This paper discusses medium term (25 years) vegetation development in five different biotopes after fire disturbance. Sample plots were established in Slitere Reserve (now National park) in north-western Latvia on areas affected by large fire in 1992. Data were collected in 1993, 2002 and 2017. The aim of the study was to characterize the regeneration and succession of ground vegetation after the fire. In 1993, species such as bog-rosemary (C) were observed in the ground vegetation a year after the fire. In 2002 liverworts appeared, indicating that the bog has acquired more stable and wetter conditions, but in 2017, liverwort mosses were no longer present and the percentage cover of Rubus chamaemorus decreased significantly and Calluna vulgaris, sphagnum sp., and Betula pendula were present in large quantities in the bog. Comparing these studied years, it can be concluded that all these years the biotopes and species have continuously developed and are regenerating.