Lab 2: Exploring Fragstats

In this lab we conducted an assessment of land use change around Edmonton, Alberta between 1966 and 1976. I focused my study on urban land use change to measure urban expansion over 10 years.

The amount of urban built-up areas in Alberta increased almost tri-fold over these ten years from 19,596 hectares in 1966 to 54995 hectares in 1976. However, the growth was seen not only in the expansion of the city core but also in an increase in number and size of disjunct areas. The urban areas were built on what was previously cropland, pastures and productive woodland. Further rapid urban growth is expected and an effective land use management plan is necessary to manage urban expansion with minimal costs to the surrounding environment.

The data used for analysis in this report was retrieved from the Open Government Portal. The analysis uses CLUMP (Canada Land Use Monitoring Program) data for Edmonton, Alberta in the years of 1966 and 1976. It includes 14 land use classes that were sorted based on air photo interpretation, field surveys and census information. ArcGIS was used to produce two maps depicting various land use classes in 1966 and 1976 (Map 1) and then looked closer at urbanization of the urban core (Map 2) and the peripheral land (Map 3). It can instantly be seen (Map 1) that both the core and peripheral areas experienced rapid urban growth over 10 years. The built-up areas increased in number and size taking over other land uses. If we look at the core urban area of Edmonton (Map 2) we can see that it grew significantly, taking over what was cropland and pasture in 1966 and replacing. As mentioned above, the amount of disjunct areas around the core also increased with urbanization moving further away from the center. If we look at the change in one of such areas (Map 3) we can see that urbanization replaced pastures, cropland and marshes.

Through using FragStat for analysis, the total area of the built-up areas class increased by 35399 hectares with the total core area increasing by 22560 hectares. Built-up areas almost triple and came to occupy 8.5407% of the study area in 1976 compared to only 3.0413% in 1966. The number of disjunct urban areas also increased from 88 to 384 within ten years indicating a shift away from the core urban area (Table 1). Although the number of patches increased greatly for urban areas from 133 to 417 the number of patches for the whole landscape decreased by 209 therefore indicating a loss in landscape diversity most likely caused by urbanization (Table 2).

To analyze where the increase in the built-up areas came from in 1976 we created a transition matrix (Table 3). We can see that built-up areas from 1966 contributed only 35.63% of the total 1976 area. Most of the 1976 built-up areas came from cropland 38.88% followed by unimproved pastures and range land 13.51% and productive woodland 5.00%. Figure 2 you can see the complete breakdown of what land use classes in 1966 have been converted to built up areas in 1976. Can conversion of productive land to urban areas can be problematic in the long term therefore it is important to understand where urban growth comes from.

In figure 1 we can see the land use total areas by classes between 1966 and 1976. We can see that most land use classes decrease in area that they occupy and the two most significant increases can be attributed to built up areas and productive woodland. The latter can be explained by the maturation of unproductive forest land from 1966 to 1976.

Table 1: Changes in class level metrics for land use in Edmonton, Alberta between 1966 and 1976.

Table 2: Changes in landscape level metrics for land use in Edmonton, Alberta between 1966 and 1976.

Table 3: Transition matrix depicting where the change in land use in 1976 came from.

Table 4: Description of class and landscape metrics used.

Figure 1: Total areas of land use classes in 1966 and 1976.

Figure 2: Land use class change to urban built up in 1976.

Map 1: Land use change between 1966 and 1976 in Edmonton, AB.

Map 2: Land use change in the core urban center of Edmonton, AB between 1966 and 1976.

Map 3: Land use change in the peripheral urban area in Edmonton, AB between 1966 and 1976.

References

Open Government Portal. n.d. Edmonton CLUMP 1966, 1976. Retrieved from

http://open.canada.ca/data/en/dataset?organization=nrcan-rncan

Kevin McGarigal. 2015. Fragstats Help. Retrieved from

http://www.umass.edu/landeco/research/fragstats/documents/fragstats.help.4.2.p

Statistics: a review

Understanding statistics is critical in GIS as we need to summarize and explore datasets and be able to identify relationships and make predictions. In this class we reviewed the kinds of data that exist, ways of summarizing it and the two main ways of looking for relations: visualizations and quantitative approaches.

One of the most important quantitative approaches in GIS that we discussed in class is regression modelling. It helps answer why we observe certain spatial patterns and if the patterns are significant or just a result of random outcomes. A number of methods can be used, such as ordinary least squares which can help determine the most important variables from the AIC, and the geographically weighted regression which we describe and apply in detail in lab 3.

Understanding landscape metrics: patterns and processes

Geography and location are fundamental in any analysis that is being conducted. In landscape ecology the focus is on the interactions between ecological processes and observed geographical patterns, how they influence and determine each other. Some methodological consideration for landscape ecology are first- (pattern as a result of environmental factor) and second-order (pattern a result of interactions) spatial autocorrelation processes, and first- (intensity constant over space) and second-order (absence of interactions) stationarity.

The main types of processes affecting landscape ecology have been discussed in lecture: abiotic, biotic, anthropogenic and disturbances. Climate, topography and soils are some of the major abiotic factors considered in landscape ecology analysis. Biotic factors include interactions between species, such as competition and predation. Anthropogenic or human influences could be such things as deforestation and urbanization. Lastly, disturbances are various natural hazards such as volcanic eruptions, fires and floods drastically change landscape ecology. Landscape ecology is determined by a combination of all these factors and the different scales that we look at them. Three main factors can be used to explain differences in spatial patterns: local uniqueness, phase differences and dispersal.

Lab 1: Spatial Statistics Using Modelbuilder Tutorial

The below map gives a hot spot distribution of heart disease rates by county in the southern United States. The data for this map was taken from CDC Wonder for the year 2016. The total deaths from heart disease were divided by the total population of the county to find the heart disease rate and normalize the data. Also a spatial weights matrix was created using the 8 nearest neighbors to run the hot spot analysis. Since this is a big dataset, and before zeroing in on 2016 I looked at years 1999 to 2016, models were created in Modelbuilder to process all of the data. The first model was designed to separate the data into 18 yearly classes and process it year by year. The second model used a hot spot analysis tool to define statistically significant hot and cold spots with confidence levels of 90%, 95% and 99%.

By looking at the results of the hot spot distribution we can immediately identify that Oklahoma has the highest concentration of heart disease cases out of all the other southern United States. The east coast and Texas have some of the lower concentrations. Further data and analysis is needed in order to determine the causes of such spatial variations of heart disease rates. Perhaps the concentration of hot spots in Oklahoma could be due to older population, poverty, unhealthy diets, poor air quality, higher caffeine consumption, or even genetically predisposed population. It could also be due to infrastructural distributions and by this I mean a higher concentration of nursing homes and heart disease centers. Any or all of these factors could play a role in determining the patterns, however that information was not available to us for the purposes of this assignment. Overall Oklahoma seems like a problematic state in terms of heart disease fatalities and I would suggest moving to Maryland which seems to be the less troubled according to this map.

Why is ‘geography’ important?

Studying geography is critical, as it often underlies other types of studies which feature any other sort of social, environmental, cultural, or economic concern. The geographic implications of a problem are an inherent factor in any analysis, and its absence can lead to unrealistic conclusions. This leads to MAUP, or the “modifiable areal unit problem”, which states first that the scale or spatial resolution of spatial analysis can lead to different statistical results, and secondly that the way that data points are aggregated into clusters can lead to different statistical results. Therefore, MAUP describes a powerful statistical and geographical issue inherent in analyzing a list of geographical data points. The MAUP is an intrinsic characteristic of all physical and abstract geographic studies.

Another example of the importance of geographical analysis in studies is the Simpson’s paradox, also called the reversal paradox or the amalgamation paradox, which describes a situation in which related trends can be found in separate groups of data, but an opposing trend can be found when those groups are combined. In conclusion, an understanding of the geographical influence in a data set is often critical before any other social, environmental, or biological conclusions can be made about a scientific analysis.

Introduction to course

GIS is useful for finding social and environmental patterns in different geographical locations. Once spatially based data has been collected, it can be analyzed to find where things occur the most, why it occurs in these locations, and how these clusters affect other contextual data. All of these conclusions can be used to optimize where things should be located within cities, communities, or any other location under study. In this class, we looked at three areas of study which were drastically improved using GIS tools: landscape ecology, crime analysis, and health geography. These three areas of study are linked by the five “p”‘s: patterns, processes, places, people and perspectives, which we will examine further in this course.

Landscape ecology is the study of how landscape patterns affect the ecological processes within a relatively local environment. The response variables used in landscape ecology statistics are abundance, distribution, and process variables. Health geography combines genetics, individual lifestyle choices, and environmental factors to find statistically based conclusions regarding disease ecology, health care delivery and accessibility, and the interaction of environmental risk and community health. Finally, crime analysis using GIS results in a more efficient crime prevention force by analyzing crime patterns and trend correlations. Analysis of crime trends has given support to theories such as the social disorganization theory, the rational choice theory, and the broken windows theory. GIS is the best method for analyzing this type of information because it combines the spatial data collection with scientific analysis and the computer software to display all the information in an easy to digest way.

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