Evaluating structural landscape development in the municipality Upplands-Bro, using landscape metrics indices

英语. The aim of this study was to evaluate and describe the landscape development in an area located in the municipality of Upplands-Bro, Sweden. The main hypothesis was that the landscape patterns in the study area have changed, as I expected to discover that the landscape has undergone structural changes, in form of both changed land use and changed landscape patch composition. The hypothesis was based on the general landscape trend according to previous research, which says that landscapes worldwide, generally become less homogeneous and more fragmented. Not least in areas like the study area, which is located in the vicinity or in connection with already existing urban environments or developing communities. The aim was achieved through land use interpretation of orthophotos and implementation of different landscape indices. The interpretation and implementation of indices made it possible to quantify and analyse the landscape change over the studied time period 1960-2015. The study mainly comprises areas in and adjacent to the town Kungsängen, north east of Stockholm, Sweden. Digital land use vector maps that show land use 1960, 1975, 1995 and 2015 were created in GIS. The landscape development was evaluated using the landscape indices Patch density, Patch area mean, S1 and S2. The objective of implementing the landscape indices, was to compare how the distribution and geometry structure of different land use patches in the study area changed over time. The Shannon Diversity Index was implemented to measure how the landscape diversity in the study area changed over time. The results of the landscape evaluation showed as expected, that the landscape in the study area has undergone structural changes under the studied period. The study concluded that there has been both a redistribution of land use and changed landscape patch composition in the study area. 31% of the total study area has had changed land use between the years 1960-2015. Over the observed period, it is possible to discern that the proportions of built-up areas and open land/pasture has increased while the proportions of forest and agriculture areas has decreased. Mainly has the land use change been concentrated to the eastern parts of the study (in the surroundings to Kungsängen), although it is possible to discern land use change in areas throughout the hole study area. The most distinctive land use development trend observed was 1), a high percentage increase in built-up areas, mainly in areas adjacent to already existing built-up areas, and 2), a large percentage decline in agricultural areas. A decrease that is largely linked to the expansion of built-up areas. For each observed year has the landscape become more fragmented, in terms of patch density. The landscape patches have also become more complex in their form. Complexity of the patch is a measure that describes how a patch deviate from an isodiametric form. The landscape development in the study area in Upplands-Bro municipality reflects the general landscape development trend that takes place in many other areas and regions around the world. Not least in near urban areas in regions that have experienced a high development and population increase. The study also showed how implementation of landscape metrics can be used when analysing landscape development and evaluating how patterns in the landscape changed over time.

英语. The landscape, an area whose appearance is the result of the influence of and interaction between natural and human factors, changes over time. It is nothing new or strange according to Eriksson and Cousins (2013), that say that human culture has affected and formed the landscape for millenniums. Development and changed landscapes can bring positive and beneficial effects for society and people’s everyday life. But the effects of landscape development can also be negative, if, for example, changes in the landscape affect plants and animals' living conditions. Which in turn can reduce populations of different species and limit important gene flow. This study whose purpose was to evaluate landscape development in an area in the municipality Upplands Bro, could conclude that the studied area that has had a high population increase, follows the general global landscape development trend that prevails right now. Which is that the landscapes around the world are becoming more and more exploited and fragmented. With the help of a mapping and analysis of how land use changed, I was able to conclude, as expected, that the landscape in the study area has changed between the years 1960-2015. The study could conclude that there has been both a redistribution of land use and changed landscape patch composition in the study area. Patches are the surfaces that make up the landscape. Around 31% of the total study area has had changed land use between the years 1960-2015. Throughout the analysis period, I distinguish two distinctive land use trends in the study area. A large percentage increase in built-up areas and a large percentage decline in agricultural areas. Forests and open/land pastures have also had varying distribution in the landscape during the evaluated period. But, unlike the classes built up areas and agricultural areas, the variation has, in percentage terms, not been as strong as for built up areas and agricultural areas. Mainly has the land use change been concentrated to the eastern parts of the study area in the surroundings to the town Kungsängen, although it is possible to see land use change in areas throughout the hole study area. Regarding the different land use patches structure and form, it is clear to see a trend in the study area. For each observed year has the landscape become more fragmented, in terms of patch density. The landscape patches have also become more complex in their form. A major reason for the increasing fragmentation, apart from increasing amounts of new buildings and industries are the establishment of new roads within the area I have studied. Roads whose main purpose is to improve mobility and provide infrastructure, is a great source to new landscape barriers and increased landscape fragmentation, not least in Sweden where this study where conducted. The results of this study provide you insights into how areas with similar development, conditions and location have been affected by landscape development. The knowledge generated can you for example use in landscape management purposes, give information about how different specific element in the landscape have been affected and promote actions that can and preserve and protect vulnerable areas in the landscape. If it is possible to map and analyse how the landscape changed, it is possible to gain knowledge and create new preconditions that can protect and preserve vulnerable locations with high biodiversity and high environmental values.