Analysis of landscape change: a numerical approach in a study of case in the polish city of Torún

This paper analyzes the relationship between a natural landscape and extreme natural phenomenon, having as the study area the neighbourhood Kaszczorek in the Vistula river valley of Toruń, Poland. The methodology combined a literature review, fieldwork in Poland and data analysis of the information obtained by applying the theory Shannon and Weaver theory in order to applied to measure the relationships between natural landscape and extreme natural phenomenon and establish combinations between some variables of the landscape. The result obtained is 9.2% of change at in the natural landscape.


Introduction
Geographical research related with numerical analysis of landscape change using photography is useful for contribute to better understand how extreme natural events affects different elements of landscape. The field of ecology of landscape (science of studying and improving relationships between ecological processes in the environment and particular ecosystems) and geographical perception can improve the information about landscape change as result of climate events. In some cases, the speed of the changes of landscape in society that makes many details goes unnoticed in as result of the urban dynamics.
It is important better understand the relationship between the human population and their environment, the human population is the primary cause of the environmental changes nowadays. Many environment effects are caused locally, although the same patterns are repeated across the world. It is important the explore knowledge that need to be harnessed for a sustainable society and applied in ecological situations (C. R. Townsend, 2008).
The frequency of elements in the landscape, when an item type more extensive than others, can be considered a relative area of the landscape. The most extensive normally controls the flow of the landscape. The structures are determinants by human influence (R. T. T. Forman & M. Gordon, 1986).
Natural risks are a public safety issue that requires appropriate mitigation measures and means to protect citizens, property, infrastructure and the built cultural heritage. Mitigating this risk requires integrated and coordinated action that embraces a wide range of organizations and disciplines. Adaptation to climate change was slow to emerge into the international climate scene. Today, however, receives growing attention at all levels.
Some details enable a reading of human action on the landscape, which can interfere in the community (e.g. dam barrage that impounds water or the change of the natural course of a river). This type of study is inserted in Cultural and Geographical theory of perception, by the comparative method (former and using current photograph).
The images represent fragments of historical moments, cultural, social possibility to monitoring the changes in the landscape.
Poland is not a country very affected by climate impacts at the Eastern Europe (S. Kreft & D. Eckstein, 2013). The

Study area and methods
The study area is the view of landscape of the neighborhood Kaszczorek in the city of Toruń on the Vistula River. The city of Toruń is situated between 52°58' and 53°04' of north latitude, between 18°32' and 18°43' of east longitude, the city covers the area of 115 km 2 (E. Adamska, 2011). Is listed on the UNESCO list of World Heritage Sites since 1997. Toruń has many monuments of architecture beginning from the middle ages. The city is famous for having preserved almost intact its medieval spatial layout and many Gothic buildings. In this research the network analysis of the areas, the numbers of pixels were count of each element considered to determine the coefficients applied using the theory of information of Shannon information theory and Weaver (1943).  Table I.    fig. 1 and fig. 2. fig. 1 e fig. 2 The surface of landscape was divided by colourful lines that correspond to the elements present in the landscape. When performing any act amending elements of the landscape, both the type of items as its quantity, and the proportion in which each element is in the landscape. Any action on the natural environment can increase diversity as it introduces one or more new elements in the landscape. Not however, one must perform reasoning from the point of view global modification generates action on the landscape. In the first case there is an irreversible modification of the landscape; in the second case the loss can be offset by measures to correct the action.

Tabela I -Elementos da paisagem analisados na
A numerical objective analysis of these two types of modifications is essential for developing preventive and corrective measures that minimize landscape impacts and understand better natural extreme events.
The flooded area is subtracted from the surfaces of the landscape elements that directly affected it. The landscape element in one situation may disappear if the action passes directly overhead, other elements will have less surface according to the amount of action that affects, the ratio "pi" these elements according with the theory of Weawer (1943) will be smaller. When performing an act amending elements of the landscape, than element (n) and size can change. It can be defined landscape impact index (IPP). Where V´ is the value of the landscape for their items before acting and V e is the value of the landscape for their items after the flood. The results can have a positive, zero, or negative.
The analysis of the Table II and Table III contain      This loss of value corresponds to the chosen lookout; it may exist more point's observation in which there will be no loss of landscape value, or in which there is a greater loss.

Conclusions
The proposed method is a numerical analysis of the landscape and provides a good tool for analyze the impact of some extreme natural phenomenon. This numerical analysis is a novel methodology in the field of impact studies regarding cases of floods. The concepts defined landscape value for their items and Index landscape impact allow objective quantification of the landscape without and with action. The approach in this research is not about the infrastructure surrounding landscape looks, but how it had changed.
The picture with the flooded area allows the analysis of landscape value with and without floods. The obtained result is 9.2% of change at the natural landscape and can be understood as the effect of the phenomenon that in this case is a flood.
It is necessary define different observation points for infrastructure proposal to allow a thorough analysis of all possible impacts landscape. The fieldwork is laborious but not difficult. It is very important to have a painstaking fieldwork that allows selecting on-site most appropriate viewpoints.