An assessment of land use change in the Niagara region between 1966 and 1976: An analysis of forest ecosystem services

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1 An assessment of land use change in the Niagara region between 1966 and 1976: An analysis of forest ecosystem services Produced for the Municipality of St. Catherine s - Niagara A good student February 1 st, 2012 Geography 479

2 Executive Summary Forests provide a variety of ecosystem services to society and are vital for song bird habitat. Forested area increased in the Niagara region during the period between 1966 and 1976 by about 33,000 hectares. During the same period, core forested area (300 meters from edges) increased by about 2,250 hectares. The majority of this change was a result of the conversion of cropland and orchard and vineyards to woodlands. This may be as a result of housing developers purchasing land to later convert it to urban developments. With this consideration, we urge the municipality to develop a comprehensive land use plan for the area, which values a range of ecosystem services. We would encourage the municipality to designated 12% of the land area to protected areas for conservation. 2

3 Introduction As described in the Millenium Ecosystem Assessment (2005), humans derive a large number of benefits from natural systems. For example, from the boreal forest, Canadians receive ecosystem services such as water purification, carbon storage, recreation and tourism (Shindler and Lee 2009). As requested by the municipality, our organization assessed the change in the amount of forested area present on the landscape, as forests can provide a range of important ecosystem services. Due to favorable climate, soils and vegetation in the Niagara region, the land is Niagara is a disputed resource (Kreuger 1978; Mueller and Middleton 1994,). While being ideal for fruit production and a pleasant place to live (Hansen 1984) it also contains vast biological resources. The Niagara region contains the Carolinian assemblage of flora and fauna, which includes many species of migratory songbirds (Mueller and Middleton 1994). Urbanization has been a driving force of land use change in Canada. Hansen (1984) found that urban areas increased in all Canadian provinces between the years 1966 and In Ontario, 90 thousand hectares of additional urban area has been observed between 1966 and 1976 (Hansen 1984). In particular, small settlements, such as towns and villages, increased by about 30 thousand hectares (Hansen 1984). The trend of increased population growth in rural areas or rural revival was observed during the period between 1951 and 1971 (Hansen, 1984, p. 74). Similar to other regions of Canada, the effect of urbanization has likely had an effect on our study region. Results and Discussion For our analysis we used the Canada Land Use Monitoring (CLUMP) data acquired from the Geogratis website. Although the data was requested at a resolution of 100 meters and 500 meters, we found the data at 500 meters was not at a resolution sufficient for analysis of land use types (Figure 3). We proceeded to 3

4 use 100 meter resolution data in our statistical analysis, using the spatial statistics program Fragstats, and the creation of a transition matrix. The trend in agricultural land and urbanization are important in explaining the trend in forested area; therefore these metrics will be included in our discussion. The most prominent trends we observed in our analysis were a decrease in cropland and land used for orchards and vineyards. Between the period of 1966 and 1976 cropland decreased by about 40 hectares and land occupied by orchards and vineyards decreased by about 19 hectares (Table 1, Figure 1) 1. During the same period prominent increases were seen in the following land use types: nonproductive woodland (31 hectares), swamp, marsh or bog (17 hectares) and urban area (10 hectares). The change in the percentage of each of these land classes as a proportion of the landscape is also available in Table 1. While the total area of cropland decreased during this time period, the number of patches (or land use parcels) nearly doubled from 455 to 855, reflecting the creation of smaller farming units (Table 1). The opposite trend was seen with the orchards and vineyards, with number of patches decreasing from 452 to 172 (Table 1). While urban land increased from 4% of the landscape to 7% of the landscape, the number of patches increased by threefold from 344 to 791, reflecting a more distributed land use pattern for urban development (Table 1). Changes were seen in the total edge and amount of core are on the landscape. While the non-productive woodland increased during this time period, the total edge associated with these woodlands also increased from about 580 km to about 2,700 km (Table 1). While productive woodlands also increased, an additional 380 km of edge was also created. This suggests the woodlands were scattered throughout the landscape. To assess songbird habitat, the core area was set to 300 m. This is a conservative estimate but was selected as disturbances from other land use types can affect songbird reproduction up to 100 meters from the edge habitat (Weakland, Wood, & Holberton, 2005). There was a substantial increased in core habitat associated with non-productive woodlands (from about 28 hectares to about 1 Please see Table 3 for a description of land use metrics discussed in this report. 4

5 2200 hectares) and non-productive woodland from about 50 to 130 hectares (Table 1, Figure 2). However, core areas of marsh, swamp or bog decreased from 720 to 280 hectares. Patch cohesion index increases as patches become more clumped or aggregated on the landscape. An increase in cohesion was seen in non-productive woodlands while decreased cohesion was seen in other areas (cropland, horticulture, and orchards and vineyards)(table 1). Forested area has decreased dramatically during the period between 1966 and Landscape level metrics can provide a greater understanding of how the landscape as a whole is changing over time. Between 1966 and 1976 the number of patches increased from about 4100 to about 5500, showing land uses were becoming more divided (Table 2). Patch density, which is based on the Number of Patches metrics, also increased slightly (Table 2, Table 3). Shannon s Diversity Index is an indicator of the diversity in different patch types on a landscape and how equitably they are distributed. This metric increased from 1.78 to 1.86, reflecting a more even distribution in 1976 (Table 2). Shannon s Eveness Index, which is similar to Shannon s Diversity Index but ranked on a scale of 0 to 1, showed a similar trend (Table 2). Amount of core area increased slightly from 68 hectares to 71 hectares, reflecting that some patches must have a shape which results in more core area. The Patch Cohesion Index decreased slightly, indicating a lower degree of aggregation of patch types on the landscape. This suggests that while there are more patches, they are more evenly distributed across the different classes. Transition matrices can be a useful tool to observe which land types are transitioning to other land types over time. Of interest to our analysis was how cropland changed over time. We observed that of the 25% of the mapped area designated as cropland in 1966, 14% was converted to non-productive woodland (Table 4). Similarly 7% of 9% of the orchards and vineyards in 1966 were converted to unimproved pasture and rangeland (Table 4). Newly created urban land in 1976 occurred as a result of land conversion cropland (1.7%), orchards and vineyards (1.1%) and unimproved pasture and rangeland (1.8%). As many of the forest patches were formerly agricultural patches, they are likely composed of generalist or invasive forest species. A similar trend was found by Muller and Middleton 5

6 (1994), who found the conversion of agriculture to forested area in the Niagara region resulted in low quality forest area. While the decreased in agricultural land and the increase in woodland may seem like a positive trend, it may be due to market speculation on housing developments. Housing developers may be purchasing agricultural land and waiting for improved market conditions to build urban developments. Although it appears that more forested areas have been created, this is unlikely to be a permanent change. Recommendations We would suggest that the Niagara region engage in a comprehensive consultation process with stakeholders in the area. We would recommend the use of the Land and Resource Management Plan (LRMP) process in British Columbia as a model for this process (e.g. Jackson and Curry (2004)). Key to this approach was the creation of a 12% protected areas strategy, as identified in the Bruntland Report, for the continued protection of ecosystem services (Jackson and Curry 2004). Mueller and Middleton (1994) also recommend a 12% protected area strategy for the Niagara area. Another vital aspect of the LRMP process was the use of stakeholder roundtables with proportional representation of different stakeholder groups (Gunton, Day, & Williams, P.W., 2003). To reduce land use conflict and ensure adequate amount of protected areas, we would propose the following: Create a broad policy directive that 12% of the land area will be protected in the Niagara region; Organize a comprehensive public consultation process for land use planning with equal representation of all stakeholder groups. Through this process address the broader social, economic and environment concerns in the region. 6

7 Literature Cited Gunton, T. I., Day, J. C., and Williams, P.W Collaborative planning and sustainable resource management: the North American experience. Environments, 31(2): Hansen, J Canadian small settlements and the uptake of agricultural land, Social Indicators Research, 15(1): Jackson, T., and Curry, J Peace in the woods: sustainability and the democratization of land use planning and resource management on crown lands in British Columbia. International Planning Studies, 9(1): Krueger, R. R Urbanization of the Niagara Fruit Belt. Canadian Geographer / Le Géographe canadien, 22(3): Muller, M. R. and J. Middleton A Markov model of land-use change dynamics in the Niagara Region, Ontario, Canada. Landscape Ecology 9(2): Schindler, D. W., & Lee, P. G Comprehensive conservation planning to protect biodiversity and ecosystem services in Canadian boreal regions under a warming climate and increasing exploitation. Biological Conservation, 143(7): Weakland, C. A., Wood, P. B., and Holberton, R. L. (2005). Cerulean warbler (Dendroica cerulean) microhabitat and the landscape-level habitat characteristics in southern West Virginia.The Auk, 122(2):

8 Table 1: Changes in class level metrics for land use in the Niagara region during the period of Total Area (hectares) Percentage of Landscape Number of Patches Total Edge (km) Total Core Area (hectares) Patch Cohesion Index Year Cropland , , Horticulture Mines quarries sand and gravel pits Non-productive woodland , Orchards and vineyards , Outdoor recreation Productive woodland , , Swamp marsh or bog , Unimproved pasture and range land , , Urban built-up area ,004 2, Water areas

9 Table 2: Changes in landscape level metrics for land use in the Niagara region during the period of Year Patch Density Shannon's Diversity Index Shannon's Evenness Index Total Core Area Number of Patches Patch Cohesion Index Table 3: Descriptions of class and landscape level metrics used in this analysis. Class Metrics Total Area Percentage of Landscape Number of Patches Total Edge Total Core Area Core Area Percentage of Landscape Patch Cohesion Index Landscape Metrics Number of Patches Patch Density Shannon s Diversity Index Shannon s Eveness Index Class metrics are calculated for each class type on the landscape. Forest, water and cropland are examples of class types. Area of each class in hectares Percentage of each class on the landscape Number of each patch type The sum of the length (m) of the edge segments (boundary with another class) for each patch type To assess warbler habitat, the core area was set to 50 m. Therefore the total core area for any class is the area (hectares) of land that is greater than 50 m from the edge of the class type. The percentage of the landscape that is core area for each class type A measure of the connected of each patch type on a landscape. Patch cohesion increases as patches become more clumped or aggregated. Landscape metrics are calculated for the entire landscape Number of patches on a landscape Is the number of patches on a landscape divided by landscape area, converted to a number per 100 hectares. An indicator of the diversity in different patch types on a landscape and how equitable the distribution of patch types is Like Shannon s Diversity Index, Shannon s Eveness Index is an indicator of patch diversity on a landscape. Shannon s eveness index ranges from 0 to 1 with 0 being low diversity and 1 being high diversity (each class type is present and equally represented) 9

10 Land area (hectares) Land area (hectare) Figure 1: Changes in class type area (hectares) for select class types in the Niagara region during the period of Figure 2: Changes in core area (hectares) for select class types in the Niagara region during the period of Core area was defined as area 300 meters from the patch edge. 10

11 Table 4: Transition matrix showing changes in land use between different class types in Niagara between 1966 and Cropland Cropland Horticulture Mines quarries sand and gravel pits Non-productive woodland Orchards and vineyards Outdoor recreation Productive woodland Swamp marsh or bog Unimproved pasture and range land Unproductive land rock Unproductive land sand Urban built-up area Water areas 1.72% 0.00% 0.11% 14.53% 0.08% 0.28% 0.53% 4.66% 2.16% 0.01% 0.01% 1.69% 0.00% 25.78% Total Horticulture Mines quarries sand and gravel Nonproductive woodland Orchards and vineyards Outdoor recreation Productive woodland Swamp marsh or bog Unimproved pasture and range land Unproductive land rock Unproductive land sand Urban builtup area Water areas 0.05% 0.00% 0.01% 0.23% 0.11% 0.01% 0.02% 0.10% 0.42% 0.00% 0.00% 0.20% 0.00% 1.15% 0.05% 0.00% 0.14% 0.00% 0.00% 0.00% 0.01% 0.03% 0.00% 0.00% 0.00% 0.01% 0.00% 0.25% 0.80% 0.00% 0.02% 0.07% 0.00% 0.05% 0.53% 0.20% 0.02% 0.00% 0.00% 0.23% 0.00% 1.94% 0.16% 0.00% 0.03% 0.58% 0.06% 0.05% 0.10% 0.39% 7.24% 0.00% 0.00% 1.09% 0.00% 9.69% 0.00% 0.00% 0.00% 0.01% 0.00% 0.67% 0.00% 0.02% 0.00% 0.00% 0.00% 0.02% 0.00% 0.72% 0.27% 0.00% 0.04% 0.16% 0.00% 0.09% 4.66% 0.34% 0.15% 0.00% 0.00% 0.37% 0.00% 6.10% 0.28% 0.00% 0.13% 0.04% 0.00% 0.01% 0.05% 0.27% 0.00% 0.00% 0.07% 0.02% 0.00% 0.88% 2.49% 0.00% 0.09% 1.93% 0.02% 0.17% 1.17% 3.36% 0.39% 0.01% 0.03% 1.77% 0.00% 11.43% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.06% 0.00% 0.01% 0.00% 0.08% 0.00% 0.01% 0.00% 0.00% 0.00% 0.01% 0.01% 0.00% 0.01% 0.00% 0.00% 0.03% 0.00% 0.07% 0.01% 0.00% 0.03% 0.01% 0.00% 0.04% 0.01% 0.14% 0.01% 0.00% 0.00% 6.57% 0.00% 6.81% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 0.00% 35.10% 35.10% Total 5.84% 0.02% 0.61% 17.55% 0.27% 1.38% 7.09% 9.51% 10.40% 0.09% 0.12% 12.02% 35.11% % 11

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