Atlantic Climate Adaptation Solutions Association Solutions d'adaptation aux changements climatiques pour l'Atlantique
Shore Zone Characterization for Climate Change Adaptation in the Bay of Fundy
By Barbara Pietersma-Perrott and Dr. Danika van Proosdij
Maritime Provinces Spatial Analysis Research Unit Department of Geography Saint Mary’s University Halifax, NS
Shore Zone Characterization [ACAS FINAL REPORT ]
Report prepared by: Dr. Danika van Proosdij and Barbara Pietersma-Perrott from the Department of Geography and Maritime Spatial Analysis Research Centre at Saint Mary’s University and commissioned by the Atlantic Climate Solutions Association (ACASA), a non-profit organization formed to coordinate project management and planning for climate change adaptation initiatives in Nova Scotia, New Brunswick, Prince Edward Island and Newfoundland and Labrador and supported through the Regional Adaptation Collaborative, a joint undertaking between the Atlantic Provinces, Natural Resources Canada and regional municipalities and other partners.
Project Management: Climate Change Directorate, Nova Scotia Department of Environment, P O Box 442, Halifax, NS B3J 2P8
Acknowledgements:
Nova Scotia Department of Natural Resources (NSDNR)
Nova Scotia Department of Agriculture – Resource Stewardship Land Protection
Maritime Provinces Spatial Analysis Research Centre (MP_SpARC)
Saint Mary’s University
Applied Geomatics Research Group (AGRG)
Disclaimer: This publication is not to be used without permission, and any unauthorized use is strictly prohibited. ACASA, the authors, the province of Nova Scotia, New Brunswick, Prince Edward Island, Newfoundland and Labrador, and the Regional Adaptation Collaborative are not responsible for any unauthorized use that may be made of the information contained within. The opinions expressed in this publication do not necessarily reflect those of ACASA, its associated provinces, or other partners of the Regional Adaptation Collaborative.
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Executive Summary
Human settlement in environments as dynamic as the coastal zone will inevitably lead to conflict between the natural variability of the coastal environment and the economic, social and cultural activities taking place within it. Climate change, notably sea level rise and large storm events will increase the vulnerability of coastal communities to coastal erosion and flooding, magnifying these conflicts. The capacity of coastal communities to adapt to climate change is directly linked to the availability of physical space and shoreline stability to allow such adaptation to take place. Maladaptive solutions (e.g. hard armouring a shoreline or rebuilding at the edge of a cliff) can exacerbate a community’s vulnerability. In order to mitigate potential negative impacts (e.g. loss of life and infrastructure), managers and planners need to better understand coastal processes and dynamics and choose adaptation responses that are appropriate for their local conditions. This requires up to date shore zone characterization including built structures and a solid understanding of the boundaries of coastal processes and historical rates of coastal change. This knowledge will improve the resilience of Atlantic Canadians to adapt to climate change, one of the central tenants of the ACAS project.
The purpose of this project was to develop an integrative GIS geodatabase of coastal zone characteristics including geomorphology, elevation, slope, vegetation, exposure, erodibility and built features as well as assessing areas of shoreline at continued risk of erosion with the Fundy ACAS study sites. This project serves as the foundation to address one of the goals of the ACAS program by “assessing the risks and vulnerabilities of select coastal communities in order to inform adaptation decision making at the local level” ( www.atlanticadaptation.ca ) which are discussed in greater detail in a series of companion reports. These include: van Proosdij & Pietersma-Perrott Best Management Practices for Climate Change Adaptation in Dykelands , Pietersma-Perrott & van Proosdij Marshland Atlas, and two MSc in Applied Science projects with associated reports: Tibbetts & van Proosdij A Relative Vulnerability Assessment Tool for Macrotidal Environments and Fedak & van Proosdij Hydrodynamic Flood Modelling within Fundy Dykelands: Windsor Case Study. Excerpts from these projects are provided within this report to illustrate the utility of the shore zone characterization for vulnerability assessment and climate change adaptation planning.
A segmentation model was developed within ArcGIS 10.0 to delineate and characterize the backshore, foreshore and nearshore zones within the Cumberland Basin and Southern Bight of the Minas Basin (Avon River and Cornwallis River Estuaries) in the Bay of Fundy, Canada. Multiple rather than one single static shoreline were chosen to reflect the hyper-tidal conditions (>14m tides). This was populated with data collected during shoreline surveys using an integrated field GIS/GPS tablet with geotag enabled camera. A total of 185 km were mapped in this manner and the remaining 329 km were characterized using all available aerial imagery for the region. Segments were catalogued using a customized decision key to characterize the shoreline. Areas of the coast were assessed for shore composition, shoreline stability, presence or absence of a cliff (consolidated and unconsolidated) and anthropogenic structures. Between 34 to 51% of the coastline in the Cumberland Basin and Southern Bight respectively are dyked. However a larger proportion (35%) of these dykes are armoured in the Southern Bight than in the Cumberland study area (18%). The lower foreshore is primarily salt marsh in both areas with 10% of this shoreline in the Southern Bight heavily eroding and 37% partially stabilized with some evidence of erosion. In the Cumberland Basin, only 0.4% was observed to be actively eroding while 48% is partially stabilized. In both areas, abandoned aboiteaux and culverts were found that were not previously identified which would affect vulnerability mapping and planning for EMO.
These data will be used to guide decision making with the Fundy ACAS study sites, particularly related to the need for additional shore protection and areas at risk. As mentioned previously, these data also serve as the foundation for detailed vulnerability assessments and adaptation planning. Although this report focuses on the Fundy ACAS sites, the methods used and classification system developed were also used by the Nova Scotia Department of Natural Resources (NSDNR) to characterize the Lunenburg and Yarmouth ACAS sites. A total of twenty-two 1:10,000 map sheets were published for the Fundy RAC areas in collaboration with NSDNR and full GIS databases were provided to Municipal and Provincial policy and decision makers. These new databases are providing a critical and accurate foundation for delineation of set-backs, zoning or development decisions and identification of
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Shore Zone Characterization [ACAS FINAL REPORT ] vulnerable areas that otherwise did not previously exist. In addition, the 1:10,000 base maps produced can serve as foundations for community mapping and visioning exercises for climate change land use planning. Examples are provided for the application of the shore zone classification system and include an assessment of dyke erosion in all areas, flood hazard assessment in Windsor, NS and a relative coastal vulnerability assessment in the Cornwallis Estuary.
This project is part of the Atlantic Regional Adaptation Collaborative (RAC) Program of the Atlantic Climate Adaptation Solutions Association (ACASA). It was completed within the Maritime Provinces Spatial Analysis Research Centre (MP_SpARC) with collaboration from the Nova Scotia Department of Natural Resources (NSDNR). The final product includes maps of the study area and an Internet Map Service (IMS).
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Table of Contents
Acknowledgements: ...... 2 Executive Summary ...... 3 List of Tables and Figures ...... 5 Acronyms ...... 7 Introduction ...... 8 Rationale and Objectives ...... 9 Methodology and Approach ...... 11 Form Type Definitions ...... 15 Solid Form Types: ...... 15 Unconsolidated or Unlithified Form Types: ...... 23 Material Definitions...... 30 Solid Material ...... 30 Unconsolidated (unlithified) Material ...... 31 Feature Definitions ...... 32 Results and Findings ...... 41 General Discussion...... 56 Conclusions and Recommendations ...... 57 References ...... 58 Appendix 1: Index of Published Maps...... 60
Appendix 2: GIS Data Paths...... 62
Appendix 3: Trimble Yuma Tablet Instructions...... 64
List of Tables and Figures
Table 1: Imagery Sources and Resolutions ...... 34 Table 2: Data Accuracy ...... 34 Table 3: Study Area Details ...... 38 Table 4: Shoreline statistics for the Cumberland Basin study area...... 42 Table 5: Southern Bight of Minas Basin ...... 46 Table 6: Variables used in the multicriteria analysis for the assessment of coastal vulnerability of the Cornwallis Estuary ...... 53
Figure 1: Conceptual diagram of variables influencing coastal vulnerability ...... 8 Figure 2: Study Area A within the Cumberland Basin and Study Area B within the Southern Bight of the Minas Basin
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Shore Zone Characterization [ACAS FINAL REPORT ] incorporating both the Avon and Cornwallis River estuaries...... 11 Figure 3: Coastal zone boundaries and definitions...... 12 Figure 4: Segmentation decision key for Backshore line ...... 12 Figure 5: Segmentation decision key for upper, middle and lower foreshore ...... 14 Figure 6: Segmentation decision key for Nearshore zone...... 15 Figure 7: Solid, Cliff, Vertical, High, Unconsolidated over solid, Solid, Bedrock, NA...... 16 Figure 8: Solid, Outcrop, NA, Low, Partially Stabilized, Solid, Bedrock, NA ...... 17 Figure 9: Solid, Platform, NA, Med, Partially Stabilized, Solid, Bedrock, NA ...... 18 Figure 10: Solid, Anthro, Breakwater, Medium, NA, Solid, Anthro, Riprap ...... 19 Figure 11: Wooden bulkhead with rock armouring classification ...... 19 Figure 12: Concrete bulkhead classification ...... 20 Figure 13: Concrete bulkhead followed by wooden bulkhead classification ...... 20 Figure 14: Solid, Anthro, Wharf. A) active wharf; b) inactive wharf constructed of wood and rock and c) inactive wharf constructed of wood and located on the lower foreshore...... 21 Figure 15: Solid, Anthro, Roadbed, Medium, NA, Solid, Anthro, Earth ...... 22 Figure 16: Solid, Anthro, Causeway, Medium, NA, Solid, Anthro, Concrete ...... 22 Figure 17: Solid, Anthro, Dyke, Medium, NA, Solid, Anthro, Earth with Rock Armouring. A) dyke with rock armouring and b) close-up of rock armouring on dyke...... 23 Figure 18: Unconsolidated, Cliff, Vertical, Medium, Not Stabilized, Unconsolidated, Clastic, Till ...... 24 Figure 19: Unconsolidated, Cliff, Steep, High, Not Stabilized, Unconsolidated, Clastic, Till ...... 24 Figure 20: Unconsolidated, Slope, Steep, Medium, Partially Stabilized, Unconsolidated, Organogenic, Agriculture ...... 25 Figure 21: Unconsolidated, Slope, Smooth, Low, Highly Stabilized, Unconsolidated, Organogenic, Agriculture 25 Figure 22: Unconsolidated, Beach, Fringing, Low, Highly Stabilized, Unconsolidated, Sand, NA. A) beach continues from upper foreshore to lower foreshore; b) beach is only in upper foreshore. It is a beach if there is no halophytic vegetation in the sand, if there is vegetation it’s a wetland with minerogenic ‘mat_type’...... 26 Figure 23: Unconsolidated, Beach, Barrier, Low, Highly Stabilized, Unconsolidated, Sand, NA ...... 27 Figure 24: Unconsolidated, Flat, Intertidal, Highly Stabilized, Unconsolidated, Mud, Unvegetated ... 29 Figure 25: Unconsolidated, Flat, Intertidal, Highly Stabilized, Unconsolidated, Mud, Vegetated...... 29 Figure 26: Low Marsh vs. High Marsh and Cliffed vs. Ramp ...... 30 Figure 27: Highly Stabilized ...... 32 Figure 28: Partially Stabilized ...... 32 Figure 29: Not Stabilized ...... 33 Figure 30: Example of shoreline delineation ...... 35 Figure 31: Cogmagun Marsh Restoration ...... 36 Figure 32: Shoreline Drawing Rules Tregothic Marsh ...... 37 Figure 33: Shoreline Drawing Rules Horton Marsh ...... 37 Figure 34: Shoreline Drawing Rules Grand Pre Marsh ...... 38 Figure 36: sample of data table for the backshore, showing attributes and level of detail...... 39 Figure 35: Example of segmentation ...... 39 Figure 37: Example of new 1:10,000 published map sheet for the Avon River...... 41 Figure 38: Shore zone classification and marsh body delineation for the Cumberland (Amherst) study area 43 Figure 39: Shore zone classification for the Avon River Estuary in the Southern Bight...... 44 Figure 40: Shore zone characterization for the Cornwallis Estuary in the Southern Bight...... 45 Figure 41: Tregothic Marsh ...... 47 Saint Saint Mary’s University – Pietersma - Perrott & van Proosdij Page 6
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Figure 42: Maximum water depth that would be recorded at each building in Windsor based on hydrodynamic simulation of a 2.2 m surge scenario or dyke breach on the Tregothic marsh ...... 48 Figure 43: Centre Burlington...... 49 Figure 44: Amherst Marsh ...... 50 Figure 45: Areas of concern, shore protection and critical elevations along NS14 and NS93...... 51 Figure 46: Photograph of eroding foreshore and slumping mud bank with shore protection along Elderkin marsh, Avon River and indicated by ‘ A’ on Figure 45. Photo taken May 31, 2011...... 51 Figure 47: Newport Town Marsh ...... 52 Figure 48: Newport Town Marsh photograph depicting slumping marsh bank ...... 52 Figure 49 : Distribution of Relative Coastal Vulnerability Index values at HHWLT plus a) 0.5m, b) 1 m, c) 1.5 m and d) 2 m storm surge, at the backshore at Wellington Marsh ...... 54 Figure 50: Results of historical rates of change analysis, as compared to the results produced for the lower foreshore at 3m total water level ...... 55 Figure 51: Comparison of model results with locations of concern identified by NS Department of Agriculture, Resource Stewardship, Land Protection section ...... 56
Acronyms
BS Backshore HHWLT High High Water Large Tide LFS Lower Foreshore MFS Middle Foreshore NS Nearshore NSDA Nova Scotia Department of Agriculture NSDNR Nova Scotia Department of Natural Resources SMU Saint Mary’s University UFS Upper Foreshore
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Introduction
Human settlement in environments as dynamic as the coastal zone will inevitably lead to conflict between the natural variability of the coastal environment and the economic, social and cultural activities taking place within it. Climate change, notably sea level rise and large storm events will increase the vulnerability of coastal communities to erosion and flooding, magnifying these conflicts. The capacity of coastal communities to adapt to climate change is directly linked to the availability of physical space and stability to allow such adaptation to take place. In order to mitigate potential negative impacts (e.g. loss of life and infrastructure), managers and planners need to better understand coastal processes and dynamics and choose adaptation responses that are appropriate for their local conditions. This requires up to date shore zone characterization including built structures and a solid understanding of the boundaries of coastal processes and historical rates of coastal change.
Both natural and anthropogenic factors have accelerated coastal erosion over the past decade. Deeper water near the coast associated with sea level rise allows for larger, more energetic waves to interact with the shoreline during storm events, increasing rates of erosion. Lack of consistent policies often leads to the systematic use of hard engineering structures without consideration for either coastal dynamics or socio-economic factors. These structures in turn negatively influence the eco-morphodynamic resilience of the coastal system to perform ecosystem function and return to an equilibrium state (Figure 1). Eco-morphodynamic resilience refers to the capacity of a coastal system (e.g. beach, cliff, marsh) to return to an equilibrium state with appropriate sediment flux, and capacity to absorb storm wave energy.
Figure 1: Conceptual diagram of variables influencing coastal vulnerability under rising sea levels (modified from Tibbetts, 2012)
The rates of coastal erosion or degree of coastal inundation are a function initially of the exposure condition entering into the coastal system. This includes the wind/wave climate for select decades, fetch (distance of open water for waves to develop), tidal range, nearshore bathymetry and shoreline orientation. Whether or not the energy reaching the coast results in either erosion or inundation depends on the local elevation, slope (influence on wave energy dissipation), shore composition (e.g. sand, sedimentary or igneous rock) and geomorphology (e.g.
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Shore Zone Characterization [ACAS FINAL REPORT ] beach, mangrove), presence of vegetation, and type of built environment (e.g. shore normal or parallel shore protection, culvert or drainage feature) (Figure 1). The exposure conditions will be magnified with rising sea level rise and potential increased frequency of major storms. Rationale and Objectives
Within the Fundy context, the extreme tidal range creates significant variability in the risk associated with a particular storm surge. One that occurs at mid to high tide is much more significant than one on a lower neap tide which may not even reach the backshore of the marsh or toe of the dyke. The ability of the coastal system to recover from the disturbance event (e.g. storm) will be influenced by the morphological resilience of the coastal system. This resiliency is controlled by an adequate sediment supply, resultant morphology after disturbance (e.g. cliff block failure vs beach scarp) and time between disturbance events. Political /institutional and socio-economic conditions will influence the choices of adaptation options. These adaptation options (e.g. hard vs soft engineering vs set-back) will create a positive or negative feedback and influence the biophysical state of the coastal environment (Figure 1) which in turn will influence the adaptive capacity of the local community to deal with climate change. Decisions will need to be made whether to protect, retreat or abandon infrastructure at the coast and detailed, current base maps are required to inform these decisions. This project takes place within the Upper Bay of Fundy ACAS study areas identified in Figure 2.
The purpose of this project is to:
• Develop a GIS geodatabase of coastal zone characteristics including geomorphology, elevation, slope, vegetation, exposure, erodibility and built features (e.g. shore protection, infrastructure) including dates of construction where available. • Gather information and provide planners and decision-makers with a more accurate base layer of geographic data for planning and visualization for sea level rise and storm surge scenarios. • Assess areas of shoreline at continued risk of erosion. • Provide a methodology that can be used as a model for other communities throughout Atlantic Canada.
Project deliverables include:
• A common methodology developed through collaboration between Saint Mary’s University, the Nova Scotia Department of Natural Resources (NSDNR) and Nova Scotia Environment (NSE). • Analysis of two priority areas including sections of: the County of Cumberland and Town of Amherst, and the County of Kings, District of West Hants, Towns of Kentville, Wolfville, Windsor and Hantsport. • Geographic Information System (GIS) files (See Appendix 2). • Mapsheets and Internet Mapping Services (IMS) application which will be processed in collaboration with NSDNR and released by NSDNR.(See Appendix 1 for Index of Published Maps) • A manual describing the classification system for Nova Scotia.
Preliminary investigation of existing shore zone classification systems of the Nova Scotia coastal zone, specifically the shore zone classification within the Canadian Coastal Information System (Sherin et al., 2003) and used within the Environmental Emergencies Mapping Program indicate that this data set might provide a useful template. No coastal GIS classification data were available for any of the study areas within the Bay of Fundy. The CCIS data are based on a dynamic segmentation model, permitting multiple attributes to be assigned to any linear feature (e.g. shoreline). Attributes were assigned based on aerial photo interpretation at 1:10,000 scale, satellite imagery, shoreline video and field visits. The shore zone character is then determined for each shoreline segment. This includes nearshore composition, shoreline type (e.g. sandy beach, cliff) and material (e.g. sand, silt, bedrock resistant or erodible), backshore material and type as well as information regarding the permanence of tidal inlets and number of channels. In addition, due to coastal development within the study region and lack of GIS files of built features, a detailed inventory of built features needed to be compiled, similar to some other areas (e.g. HRM). This would include shore protection structures (e.g. parallel to coast), groin and jetties (e.g. perpendicular to the Saint Saint Mary’s University – Pietersma - Perrott & van Proosdij Page 9
Shore Zone Characterization [ACAS FINAL REPORT ] coast), tidal barriers (e.g. culverts, aboiteau, dykes and causeways), anthropogenic drainage features (e.g. storm sewer drains, culverts, etc.), infill and dredging areas. Some of these data could be derived from existing data sets however others needed to be mapped in the field using a GPS (available through MP_SpARC or NSDNR or NSDA- Fundy). Beginning in June 2010, two students and a GIS Technician from the Department of Geography at Saint Mary’s University started walking the coastline of the Southern Bight of the Minas Basin and the Cumberland Basin in an effort to collect data regarding the shoreline composition, type and material using shoreline photographs. They also documented evidence of erosion, sedimentation, storm damage and manmade shoreline protection. They completed their fieldwork in July 2011.
This project directly addresses some key objectives of the Atlantic RAC program by addressing current exposure sensitivities and adaptive capacity:
1. Improve the resilience and adaptive capacity of vulnerable Atlantic coastal and inland communities 2. Build on existing knowledge and modify tools to better meet community needs 3. Mainstream climate change adaptation considerations into provincial and municipal land-use planning and development; infrastructure design and placements; and water management policies.
These contributions range from generating base data (including those not readily available or visible from satellite imagery) that are critical for assessing the physical and socio-economic vulnerability of select communities, to providing a framework for community visioning exercises and participatory mapping. The success of community mapping exercises and political acceptance is often linked to the accuracy and local relevance of the map being used. Participant observations can be integrated within the GIS for additional analysis. The base data collected can also be used to build local capacity within community planning departments. The findings of this work will help understand environmental conditions that shape vulnerability and capacity to adapt to climate change within and between communities. Visual examples of successful and unsuccessful choice of adaptation strategies (e.g. shore protection) within and between local communities will ideally help instill confidence in selecting strategies that permit coastal ecosystem processes to occur unimpeded and ultimately result in financial savings. This may lead to a paradigm shift in how coastal erosion is understood and solutions to those problems by introducing innovations with demonstrated effectiveness.
This report contains the findings of the project. It first provides an overview of the methodology and approach used to create a shore zone characterization including the data attributes used, the data collection method and the type of data collected. The next section summarizes results and findings of the data collected and identifies areas of dyke erosion and other areas most at risk for erosion. Examples of application of the shore zone classification system are also provided. The final sections provide recommendations and conclusions for climate change adaptation.
The intended audience of this report focuses on Municipal / Provincial policy and decision makers and includes municipal planners and engineers, NS Department of Transportation and Infrastructure Renewal, NS Department of Agriculture, Resource Stewardship, Land Protection Division (responsible for dyke maintenance) and Emergency Management Officials.
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Figure 2: Study Area A within the Cumberland Basin and Study Area B within the Southern Bight of the Minas Basin incorporating both the Avon and Cornwallis River estuaries.
Methodology and Approach Shore Zone Classification Scheme:
After a preliminary investigation of existing shore zone classification systems of the Nova Scotia coastal zone, specifically the shore zone classification within the Canadian Coastal Information System, it was concluded that this data set might provide a useful base upon which to build an up to date model. The Canadian Coastal Information System is based on a dynamic segmentation model, permitting multiple attributes to be assigned to any linear feature (e.g. shoreline) (Sherin et al., 2003). Attributes are assigned based on aerial photo interpretation at a 1:10,000 scale and shoreline video. The shore zone character is determined for each shoreline segment. This included nearshore composition, shoreline type (e.g. sandy beach, cliff) and material (e.g. sand, silt, bedrock resistant or erodible), backshore material and type as well as information regarding the permanence of tidal inlets and number of channels. The Canadian Coastal Information System was modified to meet the needs of this project including adding observed erodibility, marsh composition (e.g. low versus high marsh, cliffed versus ramped) and presence of anthropogenic structures. These features were added since they affect the resilience of the coastline. For example, a ramped marsh is more likely to dissipate wave energy and reform than a high marsh cliffed platform which will amplify wave breaking at the margin. In addition, where the Canadian Coastal Information System uses one line, this shore zone characterization project uses five lines to reflect the hyper-tidal conditions (>14m tides) and the highly dynamic intertidal zone. The use of one single shoreline would ignore important habitats occurring seaward of this line.
Zone Definitions
BACKSHORE: the upper or inner, usually dry and narrow, zone of the shore or beach, lying between the high-water
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Shore Zone Characterization [ACAS FINAL REPORT ] line of the mean spring tides and the upper limit of shore-zone process; it is acted upon by waves or covered by water only during exceptionally severe storms or unusually high tides. It is essentially horizontal or slopes landward, and is divided from the foreshore by the crest of the most seaward berm. Synonym: Backbeach, supratidal, supralittoral
FORESHORE: the lower or outer, gradually seaward sloping, zone of the shore or beach, lying between the crest of the most seaward berm on the backshore (or the upper limit of wave wash at high tide) and the ordinary low water mark; the zone regularly covered and uncovered by the rise and fall of the tide, or the zone lying between the ordinary tide levels. For the purposes of this project, the foreshore was divided into upper, middle and lower foreshore to reflect the range of differences in coastal characteristics with different tidal elevations. Syn: intertidal, littoral
NEARSHORE: extending seaward or lakeward an indefinite but generally short distance from the shoreline; specifically said of the zone extending from the low-water shoreline well beyond the breakzone, defining the area of nearshore currents, and including the inshore zone and part of the offshore zone. Depths are generally less than 10m. Syn: shallow subtidal
Figure 3: Coastal zone boundaries and definitions
A segmentation key was developed with collaboration from the NSDNR and shorelines were classified hierarchically from Form Supertype to Form Type and subtype , followed by geomorphology, features, material supertype, type and subtype . The following section provides a detailed description of these definitions. Figures 4 to 6 provide an overview of the decision key used to classify each shoreline segment.
Figure 4: Segmentation decision key for Backshore line
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Figure 5: Segmentation decision key for upper, middle and lower foreshore
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Figure 6: Segmentation decision key for Nearshore zone
Form Type Definitions
Solid Form Types: CLIFF: a sloping rock face that is steeper than 40°, usually formed by erosional processes and composed of bedrock or a combination of bedrock and unconsolidated material. Features include material deposited at the base of cliffs by mass movement processes (i.e. rock fall; talus cone.)
• vertical: a rock face at an angle of 70° or greater. • steep: a rock face at an angle of 40° to 70°. • unconsolidated over solid: a cliff that is predominantly bedrock but which contains a layer of unconsolidated material usually beyond the limit of shore zone processes. • smooth: a cliff characterized by a smooth, even surface.
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Figure 7: Solid, Cliff, Vertical, High, Unconsolidated over solid, Solid, Bedrock, NA.
a. Aberdeen Beach, Nova Scotia, Avon River Estuary
a. The amount of unconsolidated material does not matter. Classify the predominate material touching the shoreline. In this case it is solid bedrock.
b. Blue Beach, Nova Scotia, Avon River Estuary
b. Because this cliff has a rock face at an angle greater than 70° it is difficult to see on a satellite image as shown above.
OUTCROP: a low to moderately sloping (less than 40°) surface extending seaward from the backshore composed of bedrock.
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Figure 8: Solid, Outcrop, NA, Low, Partially Stabilized, Solid, Bedrock, NA
a. Aberdeen Beach, Nova Scotia, Avon River Estuary
b. Blue Beach, Nova Scotia, Avon River Estuary
PLATFORM: a horizontal or gently sloping surface (less than 10°) extending seaward from the intertidal zone, formed on rocky or rock-cliff shores by wave impact and erosion. The surface may be bare or littered with rock.
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Figure 9: Solid, Platform, NA, Med, Partially Stabilized, Solid, Bedrock, NA
Minudie, Nova Scotia, Cumberland Basin
ANTHROPOGENIC: man-made or man-modified features; includes those constructed by man for the purposes of moorage. (e.g. docks, marinas), protected anchorage (e.g. breakwater), commercial activities and features in which material is deposited for backshore protection (e.g. seawall), shore land extension (e.g. fill), or excavated by dredging (e.g. gravel extraction sites). (Howes et al. 1993)
Lines:
• breakwater: an offshore structure (wall of jetty) that protects a harbour, anchorage, beach or shore area by minimizing wave energy. • bulkhead: a retaining wall along a waterfront. A term also interchangeable with seawall is a vertical wall built for the purpose of retaining loose fill. Bulkheads are not designed to protect against flooding from high tides and storm surges like seawalls and therefore are constructed of less expensive materials like wood. Steel and concrete may also be used. (Klee, 1999) • revetment: a facing of stone or concrete to sustain an embankment. • seawall: a wall or embankment to protect the shore from erosion or to act as a breakwater. • wharf: a structure built along or at an angle to the shore of navigable waters so that ships may lie along side to receive and discharge cargo and passengers. • roadbed: the bed on which the ties, rails and ballast of a railroad rest or the earth foundation of a road prepared for travel by vehicles. • Causeway: a raised roadway across wet ground or water • Dyke: a wall or fence of turf or stone constructed to control or confine water.
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Figure 10: Solid, Anthro, Breakwater, Medium, NA, Solid, Anthro, Riprap
Breakwater
Wharf
Breakwater
Kingsport, Nova Scotia, Cornwallis River Estuary
Figure 11: Wooden bulkhead with rock armouring classified as: Solid, Anthro, Bulkhead, Medium, NA, Solid, Anthro, Wood with Rock Armouring or Riprap.
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Figure 12: Concrete bulkhead classified as: Solid, Anthro, Bulkhead, Medium, NA, Solid, Anthro, Wood with Rock Armouring or Riprap.
Figure 13: Concrete bulkhead followed by wooden bulkhead classified as: Solid, Anthro, Bulkhead, Medium, NA, Solid, Anthro, Wood with Rock Armouring or Riprap.
Evangeline Beach, Nova Scotia, Cornwallis River Estuary
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Figure 14: Solid, Anthro, Wharf. A) active wharf; b) inactive wharf constructed of wood and rock and c) inactive wharf constructed of wood and located on the lower foreshore.
a. Hantsport, Nova Scotia, Avon River Estuary
b. Horton Landing, Nova Scotia, Cornwallis River Estuary
c . Kingsport, Nova Scotia, Cornwallis River Estuary
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Figure 15: Solid, Anthro, Roadbed, Medium, NA, Solid, Anthro, Earth
Windsor, Nova Scotia, Avon River Estuary
Figure 16: Solid, Anthro, Causeway, Medium, NA, Solid, Anthro, Concrete
Windsor Causeway, Avon River Estuary
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Figure 17: Solid, Anthro, Dyke, Medium, NA, Solid, Anthro, Earth with Rock Armouring. A) dyke with rock armouring and b) close- up of rock armouring on dyke.
a.
b. Starr’s Point, Nova Scotia, Avon River Estuary
Unconsolidated or Unlithified Form Types: CLIFF: a sloping face that is steeper than 20° usually formed by erosional process and composed of unconsolidated material or a combination of bedrock and unconsolidated material. It also includes material deposited at the base of cliffs by mass movement processes (i.e. mud flows, slumping).
• vertical: a cliff with an angle of 50° or greater. • steep : an unconsolidated face at the angle of 20° to 50° • smooth: a cliff characterized by a smooth, even surface. • unconsolidated over solid: a cliff that is comprised predominately of unconsolidated material overlying a layer of bedrock; the unconsolidated material is usually within the limit of shore zone processes.
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Figure 18: Unconsolidated, Cliff, Vertical, Medium, Not Stabilized, Unconsolidated, Clastic, Till
Summerville, Nova Scotia, Avon River Estuary
Figure 19: Unconsolidated, Cliff, Steep, High, Not Stabilized, Unconsolidated, Clastic, Till
Lower Burlington, Nova Scotia, Avon River Estuary
SLOPE: horizontal to gently sloping (less than 20°) surface extending seaward from the backshore, composed of unconsolidated material and smooth, undulating or irregular in shape.
• smooth: smoothly sloping unconsolidated material. • steep : an unconsolidated face at the angle of 20° to 50°
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Figure 20: Unconsolidated, Slope, Steep, Medium, Partially Stabilized, Unconsolidated, Organogenic, Agriculture
Windsor, Nova Scotia, Avon River Estuary
Figure 21: Unconsolidated, Slope, Smooth, Low, Highly Stabilized, Unconsolidated, Organogenic, Agriculture
Windsor, Nova Scotia, Avon River Estuary
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BEACH: unconsolidated material formed by waves and currents that converge within this zone, typically with a concave profile, extending landward from the low-water line to a place where there is a distinct change in material or physiographic form (such as a cliff), or to the line of permanent vegetation (usually of the effective limit of the highest storm waves); a shore of a body of water formed and washed by waves and tides and lacking a bare rocky surface. The material and form of a beach can be highly variable.
• fringing: an accumulation of unconsolidated material formed by waves and wave-induced currents, in a narrow shore-parallel strip. Beach fringe is usually found along the base of cliffs, outcrops or slopes • pocket: a concave beach, flanked by bedrock headlands, with limited linear extent. • barrier: a narrow, elongate ridge rising above the high tide level and extending generally parallel with the shore, but separated from it by w lagoon, pong or marsh; it is extended by longshore drifting. • attached spit: a point or narrow embankment of land, commonly consisting of sand or gravel, deposited by longshore drifting and having one end attached to the land and the other terminating in open water. (Bates and Jackson, 1980) • detached barrier: a point or narrow embankment of land, commonly consisting of sand or gravel, deposited by longshore drifting. Neither end is attached to land, probably due to erosion from waves and currents. • berm: a horizontal or landward sloping bench of a beach, formed by material deposited by receding storm waves. (Owens, 1994)
Figure 22: Unconsolidated, Beach, Fringing, Low, Highly Stabilized, Unconsolidated, Sand, NA. A) beach continues from upper foreshore to lower foreshore; b) beach is only in upper foreshore. It is a beach if there is no halophytic vegetation in the sand, if there is vegetation it’s a wetland with minerogenic ‘mat_type’.
a. Kingsport, Nova Scotia, Cornwallis River Estuary
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b. Avondale, Nova Scotia, Avon River Estuary
Figure 23: Unconsolidated, Beach, Barrier, Low, Highly Stabilized, Unconsolidated, Sand, NA
Starr’s Point, Nova Scotia, Avon River Estuary
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DUNE: a low mound, ridge, bank or hill of loose, wind-blown granular material, either bare or covered with vegetation, capable of movement from place to place but always retaining its characteristic shape.
• Vegetated foredune (partially stabilized): sandy dune partially or fully vegetated by grasses and small forbs. • Un-vegetated foredune (un-stabilized): sandy dune with vegetation less than 10%. • Relict dune (fully stabilized): stabilized dune with trees, shrubs and lichens. An inactive dune whose movement is arrested by the growth of vegetation and remains after other parts of the system have been removed or have disappeared. (Glossary of Geology, Third Edition, American Geological Institute).
WATERBODY: a usually shallow depression within the shore zone continuously occupied by water.
• lagoon : usually a shallow depression within the shore zone continuously occupied by salt or brackish water lying roughly parallel to the shoreline and separated from the open sea by a barrier. The barrier provides protection from wave action although overwash may occur during storms. Sediments in lagoons are commonly fine textured, usually mud or muddy sand expected near inlets where sand tends to dominate. (Owens, 1994) • lake/pond: a natural body of permanent standing freshwater. And inland body or standing water occupying a depression in the earth’s surface. (Bates and Jackson, 1980)
FLAT: an extensive, nearly horizontal sedimentary deposit that is alternatively covered and uncovered by the tide or storms and occasionally vegetated by sea grass.
• subaerial: sedimentary deposits that are formed on or immediately adjacent to the land surface and rarely inundated. • intertidal: an extensive, nearly horizontal, unconsolidated sediment 9mostly mud and sand) deposit situated between high water and low water. Syn: littoral. (Glossary of Geology, Third Edition, American Geological Institute). • vegetated: a sedimentary deposit, typically in the shallow subtidal zone, vegetated by sea grass • non-vegetated: a sedimentary deposit that exhibits no vegetation and is typically comprised of fine sediments.
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Figure 24: Unconsolidated, Flat, Intertidal, NA, Highly Stabilized, Unconsolidated, Mud, Unvegetated
Aberdeen Beach, Nova Scotia, Avon River Estuary
Figure 25: Unconsolidated, Flat, Intertidal, NA, Highly Stabilized, Unconsolidated, Mud, Vegetated
Windsor, Nova Scotia, Avon River Estuary
WETLAND: a coastal wetland area that is periodically inundated by tidal brackish or salt water and which supports significant non-woody vascular vegetation (e.g. grasses, rushes, sedges) for at least part of the year. (Owens, 1994)
• low salt marsh: a marsh covered by all moderate and high tides and characterized by little soil development, low species diversity, hydrophilic and often halophytic pioneer species (sedges, glasswort) and discontinuous cover. (Owens, 1994) • high salt marsh: a marsh covered only by highest high tides and storms with some soil development and organic build up and a high diversity of plant species dominated by grasses and shrubs. (Owens, 1994) • restored marsh: a site where the natural hydrology has been restored, enabling the re-establishment of high salt marsh and floodplain wetland habitat conditions. • brackish: Coastal wetland that contains primarily fresh water species and some halophytes
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• ramped: salt marsh that intersects the intertidal flat as a gently sloping vegetated surface. • cliffed: salt marsh that intersects the intertidal flat as a cliff greater than 30 cm and a slope >20 0
Figure 26: Low Marsh vs. High Marsh and Cliffed vs. Ramp
Low Marsh High Marsh
Ramp
Cliffed
Hantsport, Nova Scotia, Avon River Estuary
In this example the low marsh shows signs of ramping and cliffing. Classify the furthest extent and put cliffing in the comments field.
Material Definitions
Solid Material ANTHROPOGENIC : features influences by the impact of man or man-made materials
• concrete: a mixture of cement, aggregate and water, which will set to harden to a rock-like consistency. • metal: an opaque, fusible, ductile and lustrous substance that is a good conductor of electricity and heat. • wood: lumber used for building purposes such as docks, pilings and buildings. • Rip rap: large fragments of broken rock thrown together irregularly or fitted together to prevent erosion by waves or currents and thereby preserving the surface, slope or underlying structure. (Owens, 1994) • Earth: dykes
BEDROCK: solid rock exposed at the surface or underlying unconsolidated clastic materials.
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Unconsolidated (unlithified) Material CLASTIC: sediments that contain no organic material, usually defined on the basis of the size of the particles (Environment Canada, 1994)
• mud: a mixture of water and silt or clay-sized earth material with the consistency ranging from semi-fluid to soft plastic; a wet, soft, soil or earthy mass, mire or sludge; an unconsolidated sediment consisting of clay and/or silt, together with other dimensions (sand), mixed with water, without connotation as to composition. (Bates and Jackson, 1980) <0.0625 mm (Wentworth, 1922) • sand: a rock fragment or detrital particle smaller than a granule and larger than a course silt grain, or that at the lower limit of visibility of an individual particle and that of the head of a small wooden match. (Bates and Jackson, 1980) 0.0625mm (Wentworth, 1922) • cobble: a rock fragment larger than a pebble and smaller than a boulder, being somewhat rounded or otherwise modified in the course of transport. (Bates and Jackson, 1980) 6-256cm (Wentworth, 1922) • boulder: a detached rock mass larger than cobble. (Bates and Jackson, 1980) >256mm (Wentworth, 1922) • gravel: an unconsolidated, natural accumulation of rounded rock fragments, resulting from erosion, consisting predominately of particles larger than sand (diameter >2mm), such as boulders, cobbles, pebbles, granules or any combination of these fragments; the unconsolidated equivalent conglomerate; a popularly used term for a loose accumulation of rock fragments, such as detritus sediments associated especially with streams or beaches, composed predominantly of more or less rounded pebbles and small stones, and mixed with sand that may compose 50-70% of total mass. (Bates and Jackson, 1980) • till: unstratified glacial drift consisting of clay, sand, gravel, and boulders intermingled (Merriam-Webster)
ORGANIC: of, relating to or derived from living organisms.
• Minerogenic: an unconsolidated deposit of semi carbonized plant remains and inter-bedded sediment in a water saturated environment, such as a bog or a fen, or salt marsh and of persistently high moisture content (at least 75%) inorganic matter > organic matter • Organogenic: an unconsolidated deposit of semi-carbonized plant remains in a water saturated environment, such as a bog or a fen, or salt marsh and of persistently high moisture content (Bates & Jackson, 1980). Organic matter > Inorganic matter. • peat: an unconsolidated deposit of semi-carbonized plant remains in a water saturated environment, such as a fen or bog, and of persistently high moisture content. (Bates and Jackson, 1980) • forest: land with a tree canopy cover of more than 10%. (European Environment Agency Online). • Agriculture: cultivated land used to produce crops and raise livestock. • Shrub: a low usually several-stemmed woody plant (Merriam-Webster)
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Feature Definitions
• highly stabilized: No visible signs of erosion.
Figure 27: Highly Stabilized
Greenwich, Nova Scotia, Cornwallis River Estuary
• partially stabilized: Visible signs of erosion including cliffing, however very little to no vegetation is slumping away from the shoreline.
Figure 28: Partially Stabilized
Hantsport, Nova Scotia, Avon River Estuary
• not stabilized: significant visible signs of erosion including cliffing, with vegetation slumping away from the shoreline.
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Figure 29: Not Stabilized
Wolfville, Nova Scotia, Cornwallis River Estuary
• unconsolidated over solid: a cliff that is predominantly bedrock but which contains a layer of unconsolidated material usually beyond the limit of shore zone processes.
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Digital Data Sets:
Prior to going into the field, all available GIS layers were integrated into an ArcMap Project. This included satellite imagery, aerial photography, LIDAR digital elevation model, shapefiles and survey points. The availability and age of the data varied between the study sites and by county. The NSTDB 1:10,000 Topographic Series, freely available for the province, included buildings, hydrography, designated areas, landcover, road, rail and utility networks, contours as well as other features provided the initial base data. All data are referenced to North American Datum 1983 (NAD83) CSRS UTM Zone 20 (horizontal) and Canadian Geodetic Vertical Datum 1928 (CGVD28) (vertical). The NS Coastal Series were used in a limited manner for the identification of wharf polygon features. The NS Wetland Vegetation and Classification Inventory from the NS Department of Natural Resources was used to identify additional coastal wetlands within the study area or assist in their identification from aerial photography (Milton, 2009). High resolution satellite imagery included: Quickbird (Digital Globe) and IKONOS (GeoEye) (Table 1, 2). Both satellites collect imagery every 3.5 days however archive images are the more cost effective option. Aerial photos are collected and flown every 10 years therefore availability is more limited, particularly if flown at high tide. These are supplied by the NS Geomatics Centre and were scanned and orthorectified within ArcGIS using known control points. The LIDAR data sets were provided by the Dr. Webster of the Advanced Geomatics Group at the Centre for Geographical Sciences. LiDAR or Light detection and ranging is a remote sensing technology that can measure distance and other properties of a target using pulses from a laser. These data are then transformed into a digital elevation model. Detailed descriptions of LIDAR data collection, specifications and accuracy assessments are provided in Webster et al., 2011. GPS survey of dyke centerlines were provided by Darryl Hingley from the NS Department of Agriculture. These data were collected over a range of time periods using a Leica SR530 real time kinematic GPS receiver with millimeter accuracy. Table 1 and 2 provide source and accuracy information respectively.
Table 1: Imagery Sources and Resolutions
Year Type/Resolution Source Study Area 2008 Satellite/2.4m Quickbird (DigitalGlobe)* Cornwallis River/Amherst 2007 Satellite/4m Ikonos (GeoEye)* Avon River 2005 Aerial Photo /1m NS Geomatics Centre Amherst 2003 Aerial Photo /1m NS Geomatics Centre Avon River 2002 Aerial Photo /1m NS Geomatics Centre Cornwallis River 1990, 1987 Shoreline Video Geological Survey of Canada Bay of Fundy *The Quickbird and Ikonos imagery are derived products and may not be used for redistribution in other products. GeoEye Data is owned by GeoEye, Inc. All rights are reserved by GeoEye, Inc. Includes copyrighted material of DigitalGlobe, Inc., All Rights Reserved
Table 2: Data Accuracy
Data Type Vertical Accuracy Positional Accuracy Quickbird Satellite N/A 3.5m (orthorectified to NSTDB) Ikonos Satellite N/A 3.5m (orthorectified to NSTDB) Aerial Photography N/A 2.5-3.5m (georeferenced to NSTDB) Trimble Yuma (5817A - yuma) 4-10m 2–5m 4-10m (1 -2m with GPSMAP 60CSx barometric calibration) 2-5m Leica SR530 10mm + 1ppm 5mm + 0.5ppm LiDAR 15cm 2m Nova Scotia Coastal Series varies varies
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NSTDB 1:10 000 Topographic Series 2.5m 2.5-3.5m The initial geodatabase and domain using the segmentation decision tree were set-up by Greg Baker from the Maritime Provinces Spatial Analysis Research Centre. This geodatabase was loaded into a Trimble Yuma Tablet, a handheld tablet computer with a built in GPS and camera, allowing pictures to be taken with GPS coordinates attached to the photograph. Shoreline / Shore Zone Delineation:
As mentioned previously, five shorelines were chosen for analysis. This included the backshore, upper, middle and lower foreshore as well as the nearshore (Figure 30). The foreshore polylines were digitized using satellite imagery and aerial photography, where no satellite imagery was available (see Table 1). The backshore polyline was traced from 2m resolution LiDAR data at an elevation of 7.57 metres (CGVD28) which is higher high water large tide (HHWLT) in the Southern Bight of the Minas Basin (CHS Chart 4140 at Hantsport 2002, converted to geodetic using conversion obtained from CHS, Charlie O’Reilly, per.con, 2005) and at an elevation of 7.50 metres in the Cumberland Basin. Where there were changes in the shoreline since the date of the latest satellite imagery or aerial photography, the lines were drawn based on field verification, survey data, where available and consultation with responsible parties. For example in 2009 the Cogmagun Marsh dyke was breached by CB Wetlands and Environmental Specialists Inc., changing the structure of the backshore (See Figure 31).
Figure 30: Example of shoreline delineation
The four remaining lines were determined by air photo and satellite interpretation as well as ground truthing. The middle foreshore (purple) is located between the distinct changes in the green colour seen on a satellite image from light green to rich dark green. This is a spartina dominated system where low marsh is spartina alterniflora and high marsh is spartina patens . Upper foreshore (orange) is a brownish, yellow colour on the satellite image. The lower foreshore (green line) is the furthest extent of vegetation. The Nearshore begins at the low tide mark, however as the nearshore is almost always mudflats or sand flats, it was decided to only show a line if it was different from mudflat. These division would be validated in the field by the observed vegetation types.
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Figure 31: Cogmagun Marsh Restoration
Shoreline Digitizing Rules:
A number of rules of thumb came out of the digitizing process. Where marsh vegetation ends it is appropriate to continue the line and trace over the backshore line, when there are still distinct foreshores. For example in Figure 32, although the marsh vegetation ends, the UFS is a sand beach, the MFS is a mud flat and the LFS is also a mud flat but not stabilized.
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Figure 32: Shoreline Drawing Rules Tregothic Marsh
Where river channels narrow and it becomes difficult to distinguish the UFS and MFS, it is appropriate to end these lines and continue only with the BS and LFS, as in Figure 33: Shoreline Drawing Rules Horton Marsh below.
Figure 33: Shoreline Drawing Rules Horton Marsh
Where there are high marsh areas surrounded by low marsh it is appropriate to draw fully enclosed lines around these areas as in Figure 34.
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Figure 34: Shoreline Drawing Rules Grand Pre Marsh
The resultant polylines were placed in a file geodatabase. A geodatabase is advantageous as it acts as an organizational tool to store and manage data; it also supports many different types of data. Working within a geodatabase also allows for use of drop down menus when entering data(coded value domains) and topology rules can also be used to ensure data integrity (i.e. line features do not overlap).
Field Data Collection and Verification:
The Trimble Yuma tablet computer with integrated GPS and a geotag enabled camera were used to document changes in shoreline composition. A total of 185 kms of the coastline were walked, representing approximately 36% of the total coastline within the study areas and was limited primarily by accessibility and safety (Table 3). The Yuma tablet attaches GPS coordinates to each photograph which allows for the photographs to be displayed within a GIS environment. At every area of change, for example from a beach to a marsh, a photograph was taken. A fieldbook was used to note all of the changes according to a decision key created for each shoreline (Figures 4-6) and paper maps were used to mark the exact location of the changes. In areas where field verification was not possible, satellite imagery, aerial photographs and shoreline video was used to determine classification (see Table 1).
Table 3: Study Area Details
Pictures Length of % of coastline Study Area Field Days Km’s Walked Taken Coastline** Walked Amherst 5 days Beginning 182* 71 km 181 km 40%
08/20/2010 Southern 13 days Bight Beginning 1281 114 km 333 km 34% 07/19/2010 and 05/24/2011 *53 not geotagged, ** 1:10,000 NSTDB Coastline
To document changes in shoreline characteristics the appropriate line was selected and split using the editor toolbar in ArcGIS 10 and the appropriate attributes were selected (Figure 35).
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Figure 35 : Example of segmentation
Figure 36: sample of data table for the backshore, showing attributes and level of detail.
An additional polyline was created representing shore protection or rock armouring. Data were collected from field observations and associated with a particular shoreline.
Non-agricultural aboiteaux and culverts were documented as point features. The features were observed in the field or surveyed with handheld GPS ( GPSMAP 60CSx 2.5 m accuracy) by a Master’s student. These are structures which are not usually along dykes and therefore not likely managed by the NSDA. Agricultural dykes and aboiteaux survey data were provided by the NS Department of Agriculture. The data were surveyed using a Leica SR530 (Table 2). In the field, photographs were taken of every aboiteau and these photographs were added to the survey data. Additional aboiteau data (i.e. construction date, length, diameter, type of gate) provided by the NSDA were also added to the survey data. Points of access were also documented to allow future researchers to easily access dykes and marshes.
Wharf structures were documented using field observation and recorded as a polygon. As well, wharf or port Saint Saint Mary’s University – Pietersma - Perrott & van Proosdij Page 39
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Building polygon s were obtained from the Nova Scotia Geomatics Centre (NSGC). It is an internal dataset and the accuracy of the data varies, however it provides more detail than the existing 1:10,000 data available. The building polygons were intersected with the NSGC’s Property Records Database to show building ownership and a field was also added to the data to indicate the type of building (ie. Church, school).
Finally, a habitat polygon was created by field observation and airphoto/satellite interpretation using the same image sources as described in Table 1. The polygon shows different types of areas such as: high and low marsh, rocky outcrops and beaches.
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Results and Findings
A total of 22 new map sheets were produced incorporating both the 1:10,000 provincial topographic map and new shorezone characterization completed within this project including areas of erosion. Figure 37 depicts an example of map sheet produced. Appendix 1 provides an index of the published maps.
Figure 37: Example of new 1:10,000 published map sheet for the Avon River.
Because the data are contained within attribute tables within a GIS, users are able to query the database with minimal effort. For example, a municipal engineer may wish to know the total length of coastline within their jurisdiction that may require shore protection due to active erosion in order to produce accurate cost estimates to present to council. Within the Southern Bight, 11 kms of backshore are not stabilized and 118 km will likely need to be closely monitored. Since the database is spatial, the engineer will also know the exact location of these eroding segments and will be able to know the type and condition of existing shore protection without having to spend time in the field. Interestingly there are 2 sections of backshore (~400m) within the Cornwallis estuary that are armoured with car bodies and washing machines which pose an environmental hazard. In addition, by including of different shore zones (e.g. backshore vs foreshore), the same engineer can easily identify areas that have healthy foreshore saltmarsh that would perform a natural buffer against wave energy and would be a lower priority for the use of expensive armour stone. Since the database integrates all existing municipal and provincial datasets, a planner may perform a spatial query (e.g. distance from eroding coast to municipal infrastructure such
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Shore Zone Characterization [ACAS FINAL REPORT ] as a sewage treatment plant) and, by knowing the rate of erosion, be able to predict an estimated time frame before which one would need to move the facility. The database is also useful to identify potential areas of retreat including currently dyked areas that may be candidates for salt marsh restoration and therefore serve both ecosystem function and absorptive capacity for wave energy.
Table 4: Shoreline statistics for the Cumberland Basin study area.
Backshore Upper Foreshore Middle Foreshore Lower Foreshore Feature Length in Feature Length Feature Length Feature Length Features % % % % Count KM Count in KM Count in KM Count in KM highly stabilized 34 47 40 30 61 63 11 43 28 30 66 41 NA 48 61 51 5 11 12 4 15 10 2 17 11 not stabilized 0 0 0 3 2 2 6 12 7 1 1 0 partially stabilized 7 4 3 25 23 23 54 85 55 53 76 48 unconsolidated over solid 9 6 5 1 1 1 1 1 0 0 0 0 TOTAL 98 118 100 64 98 100 76 156 100 86 160 100 Feature Length in Feature Length Feature Length Feature Length FormType % % % % Count KM Count in KM Count in KM Count in KM anthro 48 61 51 1 0 0 0 0 0 0 0 0 bar* 00 0000000000 beach 0 0 0 777432000 cliff** 11 8 7 0 0 0 0 0 0 0 0 0 flat 0 0 0 1 0 0 11 11 7 43 66 41 NA 0 0 0 4 11 12 4 15 10 2 17 11 outcrop 0 0 0 11 1 2 2 1 1 0 0 platform 0 0 0 0 0 0 0 0 0 1 0 0 slope 26 36 30 0 0 0 0 0 0 0 0 0 waterbody** 0 0 0 0 0 0 0 0 0 0 0 0 wetland 13 13 11 50 79 80 55 124 80 39 77 48 TOTAL 98 118 100 64 98 100 76 156 100 86 160 100 *Attribute is only applicable to foreshores. ** Attributes are only applicable to backshore. Armouring NA 11 18NA 1 1NA 2 1NA 0 0
In the Cumberland Basin, 40% of the backshore is highly stabilized and consists primarily of dyked anthropogenic features followed by slope. The majority of the foreshore consists of salt marsh (Figure 38) and approximately 50% is partially stabilized. Eighteen percent of the backshore is armoured (11 km), mostly by armour stone and minimal areas of foreshore are protected (Table 4). Fifty-three percent of the characterizations were verified by field observations and 42% by aerial photography. Hard armouring of the foreshore is almost non-existent. Two primary areas of active erosion and unstable slopes were observed along the western edge of Minudie Marsh and southern section of Amherst Point (Figure 38). John Lusby marsh has minimal intertidal flats and foreshore therefore is also as risk.
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Figure 38: Shore zone classification and marsh body delineation for the Cumberland (Amherst) study area
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Figure 39: Shore zone classification for the Avon River Estuary in the Southern Bight.
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Figure 40: Shore zone characterization for the Cornwallis Estuary in the Southern Bight.
Thirty-five percent of the backshore within the Southern Bight is partially stabilized and partially stabilized foreshore (e.g. cliffed with low marsh growing below) indicates a period of marsh growth which may assist in shore protection. This system is much sandier than the Cumberland study area with beach evident within the upper foreshore along 21% of the shoreline. The area is heavily dyked (31%) but also includes 48% areas of slope. More shore armouring was employed (31% of coastline) than in the Cumberland area, likely associated with the higher population density (Table 5). The foreshore is mostly dominated by salt marsh vegetation. Considerable erosion was observed along the Avon and St. Croix Rivers, mostly associated with the outer meander bends of the intertidal channels (Figure 39). In the Cornwallis estuary, the majority of erosion/instability is recorded along the middle foreshore adjacent to Grand Pre Marsh as well as the banks of the Cornwallis River (Figure 40).
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Table 5: Southern Bight of Minas Basin
Backshore Upper Foreshore Middle Foreshore Lower Foreshore Nearshore Feature Length in Feature Length Feature Length Feature Length Feature Length Features % % % % % Count KM Count in KM Count in KM Count in KM Count in KM highly stabilized 102 86 26 110 153 86 111 128 50 436 296 53 0 0 0 NA 153112 33 4 1 0 3 0 0 4 1 0 2124 1 not stabilized 21 11 3 15 5 3 38 22 8 50 57 10 0 0 0 partially stabilized 133 118 35 44 19 11 126 109 42 471 207 37 0 0 0 unconsolidated over solid 20 9 3 0 0 0 0 0 0 0 0 0 0 0 0 TOTAL 429 337 100 173 178 100 278 258 100 961 561 100 21 24 1 Feature Length in Feature Length Feature Length Feature Length Feature Length FormType % % % % % Count KM Count in KM Count in KM Count in KM Count in KM anthro 153106 31 4 1 0 3 0 0 4 1 0 0 0 0 bar* 00 0000000000215 beach 0 0 0 44 38 21 23 25 10 15 13 2 0 0 0 cliff** 53 35 10 0 0 0 0 0 0 0 0 0 0 0 0 flat 0 0 0 9 3 2 0 0 0 102 71 13 18 22 95 NA 16 200024104000000 outcrop 0 0 0 6 2 1 4 3 1 549 2 0 0 0 platform 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 slope 197163 48 0 0 0 0 0 0 0 0 0 0 0 0 waterbody** 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 wetland 25 27 8 110 134 76 224 220 85 786 467 83 0 0 0 TOTAL 429 337 100 173 178 100 278 258 100 961 561 100 21 24 100 *Attribute is only applicable to foreshores. ** Attributes are only applicable to backshore. Armouring NA 33 31 NA 3 1 NA 1 0 NA 2 0 NA NA NA
Applications:
Dyke Erosion and Hazard Assessment
During fieldwork a number of dykes were identified that showed visual evidence of erosion as well as failing rock armouring. These dykes were Tregothic (NS068) (Figure 41), Centre Burlington (NS 048) and Amherst (NS 042) (Figure 39, Figure 38). The implication for climate change adaptation and planning are significant. The Tregothic dyke alone protects a minimum of $31 M dollars worth of infrastructure within the Town of Windsor (Browning, 2011) therefore a breach in that location would be catastrophic (Fedak and van Proosdij, 2012). The integration of the shore zone classification within the mesh for the hydrodynamic model identified zones of weakness or conduits for water not otherwise identified. A 10.3 m geodetic water level (2.2. m surge above HHWLT) would result in houses being inundated by as much as 4 m of water (Figure 42).
The Centre Burlington marsh is a good example where maintenance of the dyke may or may not be viable due to the limited area that the dyke currently protects (Figure 43), however value of the land has not been taken into consideration. Significant erosion around one of the aboiteau at Amherst point is evident on Figure 44 and once again will potentially cause a breach to occur during a major storm event, flooding valuable agricultural land as well as valuable infrastructure in the region.
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Figure 41: Tregothic Marsh
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Figure 42: Maximum water depth that would be recorded at each building in Windsor based on hydrodynamic simulation of a 2.2 m surge scenario or dyke breach on the Tregothic marsh (from Fedak and van Proosdij, 2012)
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Figure 43: Centre Burlington
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Figure 44: Amherst Marsh
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Figure 45: Areas of concern, shore protection and critical elevations along NS14 and NS93. Cartography produced by Barbara Pietersma, 2012 (from van Proosdij et al., 2012).
Figure 46: Photograph of eroding foreshore and slumping mud bank with shore protection along Elderkin marsh, Avon River and indicated by ‘ A’ on Figure 45. Photo taken May 31, 2011.
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The geodatabase can be queried to identify areas that satisfy certain criteria. For example, a query could be performed to identify areas where two or more more foreshores are classified as partially stabilized or not stabilized and where rock armouring is present are believed to be actively eroding (Figure 47, Error! Reference source not found. ). These areas could be prioritized for repair.
Figure 47: Newport Town Marsh
Figure 48: Newport Town Marsh photograph depicting slumping marsh bank (Location shown in Figure 39)
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Relative Vulnerability Assessment One of the most comprehensive uses of this shore zone classification system is in the development and application of a coastal vulnerability assessment tool. This is discussed in detail in Tibbetts and van Proosdij (2012) and Tibbetts’ Master’s thesis however will be described briefly in this section as an example. As indicated in Figure 1, the vulnerability of the coastal zone is a function of the exposure condition, biophysical state or physical condition and resilience of that particular section of coast. The shore zone GIS can be used within a multi-criteria evaluation in which data are standardized, various weights are assigned to classes of variables, these variables are added or multiplied together and a final vulnerability assessment is returned. The variables used in the analysis by Tibbets (2012) include those directly from the shore zone classification and derived variables (e.g. slope, exposure, width of foreshore). The variables used in this analysis are; freeboard, observed erodibility, coastal slope, width of foreshore, the presence of anthropogenic or natural protection, the presence of vegetation and coastline exposure (fetch length, dominant wind direction, and significant wave height). A summary of these variables is found in Table 6 and are explained in more detail in Tibbetts and van Proosdij, 2012.
Table 6: Variables used in the multicriteria analysis for the assessment of coastal vulnerability of the Cornwallis Estuary (from Tibbetts 2012).
Variable Remarks Freeboard Freeboard is the height of the coastline (either backshore, upper, middle or lower foreshore) above the total water level (tide elevation plus storm surge). Coastline Coastline exposure is concerned with how the coastline is exposed to Exposure wave energy; exposure to less or more energy will influence the coastal environment’s vulnerability. Exposure is determined through dominant wind direction, fetch length and water depth calculated using WeMo (Fonseca and Malhotra, 2010) Width of Foreshore A coastline with a wide foreshore is considered to be less vulnerable than one with a narrow foreshore because the features within these systems act as a method to dissipate wave energy. Presence of Vegetation Naturally occurring vegetation, such as plants and shrubs can shield the coastline from the forces of waves. This has been called ‘Bio- shielding’. The presence of vegetation will result in a coastline being less vulnerable than a location that lacks these features. Coastal Slope Coastal slope is linked to the susceptibility of a coastal segment to erosion during a storm surge event; where steep slopes are more vulnerable than gentle slopes Observed Erodibility Erodibility refle cts the observed ability of a coastal feature to resist erosion. Highly stabilized features are able to withstand the impacts of sea level rise and storm surges more efficiently than partially stabilized or un-stabilized features. Anthropogenic or The presence of groins, dykes, breakwaters, outcrops and cliffs will Natural Protection influence wave propagation. If these structures are present, a coastline will be less vulnerable than one without. Morphological Resilience reflects the ability of a coastline to cope with and recover Resilience from exposure to a short term hazardous event. The innovation of this vulnerability assessment tool is its dynamic nature and ability to rapidly re-calculate vulnerability based on different tide scenarios ( Figure 49).
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Figure 49 : Distribution of Relative Coastal Vulnerability Index values at HHWLT plus a) 0.5m, b) 1 m, c) 1.5 m and d) 2 m storm surge, at the backshore at Wellington Marsh, in the Cornwallis Estuary (from Tibbetts and van Proosdij, 2012)
The results of the vulnerability assessment tool are in agreement with the literature in regards to the effects of tide elevation on potential impact of storm surge. As discussed in Desplanque and Mossman (2001), tide elevation is
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Shore Zone Characterization [ACAS FINAL REPORT ] highly influential in the overall impact of a storm surge. If a storm surge occurs at high tide, there is potential for a greater impact than if the same storm surge occurs at low tide. The results of the vulnerability assessment are then compared to historical rates of erosion calculated using historical aerial photographs and the program AMBUR (Jackson, 2011).
Figure 50: Results of historical rates of change analysis, as compared to the results produced for the lower foreshore at 3m total water level (from Tibbetts and van Proosdij, 2012)
Compared to similar vulnerability assessment tools, this research goes further by assessing vulnerability dynamically. Previous studies assessed vulnerability at a static or mean tide elevation; using the shore zone classification system as a base, Tibbett (2012) successfully designed a tool within a GIS, which accounts for changing tide elevation and its influence on storm surge potential. In addition, the resultant vulnerability scenarios can serve as the foundation for discussions with EMO and managers responsible for dykeland maintenance to identify areas of existing concern (
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Figure 51) or road closures, etc...
Figure 51: Comparison of model results with locations of concern identified by NS Department of Agriculture, Resource Stewardship, Land Protection section (from Tibbetts, 2012)
General Discussion
Field Logistics and Technology
Segmenting lines with the Yuma Tablet was cumbersome and slowed fieldwork down as there were five lines to edit and segment. The Yuma Tablet used had an ArcView licence, which may have contributed to the slow editing speeds; as well there was a large amount of basedata loaded onto the Yuma Tablet including high resolution satellite imagery and 1:10,000 basedata. As a result researchers primarily used paper maps to mark segments and used the Yuma Tablet to pinpoint locations and to photograph changes. A field book was used to record the classification of each line segment drawn or indicated on the paper maps. In the future it may be worth considering the use of ArcPad software. ArcPad may be faster at drawing and editing features as it is designed to work on mobile devices with very little processing power. A downside to ArcPad is that it does not support geodatabases, so data would have to be converted back and forth to ArcPad AXF format. Instead of using paper maps to mark segments and to draw in other features such as armouring, it is recommended that Arc’s Tablet Toolbar be used to create digital notes, which can be more easily saved than paper notes. A definite benefit of using the Yuma Tablet was the ability to geo- tag photographs allowing the photographs to be viewed in a GIS environment exactly where the photos were taken. In the field it is important to remember to enable the GPS on the camera and to set the camera resolution to Saint Saint Mary’s University – Pietersma - Perrott & van Proosdij Page 56
Shore Zone Characterization [ACAS FINAL REPORT ] the highest setting (please see Appendix 3 for Yuma Trimble instructions). Effectiveness of Classification
During the course of fieldwork a number of features were identified which were difficult to classify using the shore zone classification developed for this project. For example rock armouring was captured in the comments field, if it were captured in a separate field it would be easier to symbolize and query. As a consequence of armouring being captured as a comment, the armouring data were exported and saved as a separate feature class, making it difficult to update and maintain. Also for all anthropogenic features there was no way other than the comments field to identify stability or signs of erosion. There were a number of dykes in the study area which had signs of erosion and signs of erosion with armouring placed to protect the dykes. Foreshore and Nearshore flats also presented the same classification issue. Although cliffed flats were seen during fieldwork, the shore zone classification developed did not allow for these attributes to be classified.
Shoreline Delineation
The use of five separate shorelines rather than one was demonstrated to be very effective in this macrotidal area. From a GIS perspective it was easier to edit five distinct lines than five lines in one location. Initially the project started with the 1:10,000 provincial coastline to represent the five coastal zones, however this was abandoned in favor of five distinct representative lines which is more representative of the wide intertidal zone and tidal range (>14m) of the study area. The one shortcoming of using five lines is that the data are not part of a true dynamic segmentation model, where one line represents many attributes. A good example of dynamic segmentation is a road network, where road speed, accidents, road quality and other attributes can be represented on one line and then analyzed. For example one can easily determine if car accidents are happening at higher or lower speeds and if these accidents can be attributed to road quality.
Usefulness for Climate Change Adaptation Management
The capacity of coastal communities to adapt to climate change is directly linked to the availability of physical space and capacity of that space to accommodate both coastal processes and anthropogenic development. In order to mitigate potential negative impacts (e.g. loss of life and infrastructure), managers and planners need to better understand coastal processes and dynamics and choose adaptation responses that are appropriate for their local conditions. This report demonstrates the utility of developing and applying up to date shore zone characterization including built structures and its application to vulnerability assessment and planning. The physical structure of the database is such that it should be relatively easy to integrate into existing municipal GIS systems. This knowledge will improve the resilience of Atlantic Canadians to adapt to climate change, one of the central tenants of the ACAS project.
This project directly addressed some key objectives of the Atlantic RAC program by addressing current exposure sensitivities and adaptive capacity:
1. Improve the resilience and adaptive capacity of vulnerable Atlantic coastal and inland communities 2. Build on existing knowledge and modify tools to better meet community needs 3. Mainstream climate change adaptation considerations into provincial and municipal land-use planning and development; infrastructure design and placements; and water management policies.
There were a number of features collected during this project that are not part of any publically available data. For example a number of culverts were surveyed with handheld GPS in the Tregothic Marsh area (Windsor, NS). These structures are important when doing any flood risk analysis. As well, the location of rock armouring was also collected and these data may be important to managers when deciding where to place additional armouring or under what conditions existing protection is failing. The geotagged photographs also provide evidence as to the state of armouring, whether it be sparse or falling into the foreshore. The use of five shorelines also helps to visualize the width of the foreshore and has been used to calculate the width of foreshore (Tibbetts, 2012). This is of direct relevance to NS Department of Agriculture personnel as there is a direct correlation to foreshore width Saint Saint Mary’s University – Pietersma - Perrott & van Proosdij Page 57
Shore Zone Characterization [ACAS FINAL REPORT ] and dyke vulnerability (van Proosdij et al., 2012). These data are critical for cost-effective prioritization of shore protection efforts particularly along vulnerable dykes. Mitigation efforts can then be targeted to particular coastal segments. In addition, these data can be used to guide differential set-back target, with wider segments in areas that are actively eroding.
Conclusions and Recommendations
The development of a comprehensive shore zone characterization geodatabase can significantly improve a community’s ability to plan and respond to increased hazards of coastal erosion and storm surge associated with climate change. Ideally this database can be integrated into municipal planning GIS systems and compliment or inform decision making regarding set-backs or exclusion zones for development to adapt to climate change. In addition, it can assist in the prioritization of areas that require immediate intervention to prevent costly damage to infrastructure and livelihoods.
From a GIS and database development perspective, the use of five lines to represent the shoreline was effective as it was representative of the habitats and the different types of coastal zones in the study area. Satellite imagery was used because it was captured at low tide, whereas aerial photography was not consistently taken at low tide and only used where no satellite imagery was available. In the future it would be beneficial to source satellite imagery of the entire extent of the study area and at a consistent resolution and time period, to allow for consistent digitization of shorelines. While aerial photography is usually less readily available and updated less frequently than satellite imagery, it is quite beneficial in identifying features, especially marsh features. While backshore cliffs are easily identifiable on satellite imagery, cliffing of the foreshore was more difficult to identify and this is where the higher resolution of aerial photographs helps to identify these marsh features. Another option not considered for this project but may be worth considering is viewing aerial and satellite imagery using stereoscopic vision. With stereoscopic vision “the interrelationship between features and the real world becomes clearer, photo interpretation becomes more accurate and complete, and spatial accuracy is increased” (Bohnenstiehl 2002). ERDAS Stereo Analyst and PCI OrthoEngine are two software packages available.
Overall as a planning tool, the shore zone characterization introduced features that are not part of existing datasets available in Nova Scotia and as stated earlier these features are important to planners and managers to effectively plan adaptation strategies to deal with climate change. In addition, it can serve as a basis for the development of value added analyses including exposure sensitivity, width of foreshore and relative coastal vulnerability.
In collaboration with the NS Department of Natural Resources, Saint Mary’s University has published a series of 22 maps (7 for the Cumberland Basin and 15 for the Southern Bight) which depict some of the data collected during this project. Published data includes the location of all NSDA marsh bodies, location of dykes and aboiteaux as well as backshore and foreshore armouring. The maps also include lidar data and depicts where the coastline is highly stabilized versus partially stabilized and not stabilized. These maps will be made available online through the Mineral Resources Branch of the NSDNR. http://www.gov.ns.ca/natr/meb/ . These published maps make an excellent resource for municipal planner in identifying shorelines which are sensitive to erosion as well as identifying the NSDA incorporated marshes and rock armouring along dykes and foreshores.
References
Bates, R.L and Jackson, J.A.,1980.Glossary of Geology.2 ed. American Geological Institute, Falls River, Va
Bohnenstiehl, Kyle. “Stereo Feature Collection Software for GIS: From 2-D to 3-D Databases.” 29 Aug. 2002. Web. 4 Jan. 2012
Canadian Coastal Information System (CIS). Government of Canada, Natural Resources Canada, Earth Sciences Saint Saint Mary’s University – Pietersma - Perrott & van Proosdij Page 58
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Sector, Sedimentary and Marine Geoscience Branch, Geological Survey of Canada (Atlantic).
Daly, R.A. (1902) The geology of the northeast coast of Labrador. Harvard College. Museum of Comparative Zoology. Bulletin 38, Geological Series 5, p205-270.
Desplanque, C., and Mossman, D., 2001. Bay of Fundy tides. Geoscience Canada . 25(1), 1-11.
Fedak, M. and D. van Proosdij. 2012. Hydrodynamic Flood Modelling within Fundy Dykelands: Windsor Case Study. Final report submitted to Atlantic Climate Adaptation Solutions Association, Climate Change Directorate, Nova Scotia Department of Environment. 73pp.
Fonseca, M.S. and Malhotra, A., 2010. WEMo (Wave Expose Model) for use in ecological forecasting. Applied Ecology and Restoration Research Branch NOAA, National Ocean Service. URL: http://www.csc.noaa.gov/digitalcoast/tools/wemo/index.html .Accessed on May 30, 2011
Jackson, C.W., Jr., 2010. Basic user guide for the AMBUR package for R, version 1.0a. Unpublished.
Klee, Gary A., 1999. The Coastal Environment: Toward Integrated Coastal and Marine Sanctuary Management, Prentice Hall, Upper Saddle, N.J.
Milton, Randy, 2009: Nova Scotia Wetland Vegetation and Classification Inventory; Nova Scotia Department of Natural Resources, Wetlands and Coastal Habitats Program. http://www.gov.ns.ca/natr/wildlife/habitats/wetlands.asp
Owens, E.H.,1994. Coastal Zone Classification System for the national sensitivity mapping program. Internal Report, Environment Canada. Cat.No.En 40-488/1995E, Dartmouth, N.S.
Porsild, A.E.,(1938) Earths mounds in unglaciated Arctic northwestern America. Geographical Review. V.28, p.46- 58.
Reineck,H.E. and Singh, L.B.,1980. Depositional Sedimentary Environments with Reference to Terrigenous Clastics. Springer-Verlag, New York, N.Y.
Sherin, A.; Fraser, P.; Solomon, S.; Forbes, D.; Jenner, K.; Hynes, T.; Lynds, T and P. Gareau. 2003. A decade in the life of a coastal information system. Proceedings of the 2012 CoastGIS conference, Genova, Italy.
Tibbetts, J. 2012. Assessing Relative Coastal Vulnerability in a Macrotidal Environment to Increased Risk of Storm Surges due to Climate Change. Unpublished Masters of Applied Science thesis, Department of Geography, Saint Mary’s University, 168pp.
Tibbets, J and D. Van Proosdij. 2012. A Relative Vulnerability Assessment Tool for Macrotidal Environments: A case study from the Cornwallis River Estuary, Bay of Fundy, Canada. Final report submitted to Atlantic Climate Adaptation Solutions Association, Climate Change Directorate, Nova Scotia Department of Environment. 59pp. van Proosdij, D.; Page, S. and J. Tibbetts. 2012. Best Management Practices for Climate Change Adaptation in Dykelands: Recommendations for Fundy ACAS sites. Final report submitted to Atlantic Climate Adaptation Solutions Association, Climate Change Directorate, Nova Scotia Department of Environment. 126 pp.
Webster, T.; Guigan, K. and C. MacDonald. 2012. Lidar processing and flood risk mapping for coastal areas in the district of Lunenburg, Town and District of Yarmouth, Amherst, Cumberland County , Wolfville and Windsor. Final report presented to ACASA
Wentworth, C.K.,1922. A scale of grade and class terms for clastic sediments. Journal of Geology , 30:377-392.
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Encyclopaedia Britannica Online. http://www.britannica.com/
European Environmental Agency. http://glossary.eea.eu.int/EEAGlossary/
Merriam Webster Online. http://www.merriam-webster.com
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Appendix 1: Index of Published Maps
Southern Bight of Minas Basin
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Cumberland Basin
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Appendix 2: GIS Data Paths
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1:10,000 base data from the Nova Scotia Geomatics Centre
Other Features from various sources. See metadata for each feature class.
Yuma Tablet Photos
Shore Zone lines
Survey data provided by NSDA
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Appendix 3: Trimble Yuma Tablet Instructions
1. Turn on Virtual GPS a. Double click on “Virtual-GPS” icon on the Desktop. b. Click “Continue” c. Click “Start V-GPS” (Ensure you have a Lat. And Long. Coordinate) d. Leave “Virtual-GPS” application minimized in background.
2. Open ArcMap a. Double click on “ArcMap” icon on the Desktop.
b. Use the “GPS” toolbox on the “Open Connection” button, you should see a point indicating your GPS location after opening the connection.
c. If the point does not appear “Pan to GPS Location” , if the point still does not appear “Close the Connection” , open the GPS drop down menu and slect “GPS Connection Setup” then click on the “Detect GPS Port” and then “Open Connection” again.
3. Start Editing Session a. Click “View”, Toolbars”, “Editor” to turn on “Editor” toolbar.
b. Click “Editor” and in the drop down menu select “Start Editing” c. Make sure the Target box has the correct layer selected for what you are editing.
4. Splitting Lines Used to split line features into two or more line features. Ex: If a coastline changes from one material to another, the attributes change but the actual path of the coastline does not. a. Select the line you would like to split b. Click the Split Tool found in the “Editor” toolbar. c. Click where the change occurs. The line is now split
5. Snapping Snapping ensures that the split point where the second line segment begins is exactly where the first line segment ends. This keeps the line continuous.
a. Click the “Editor” and select “Snapping” from the drop down menu. b. Under the correct layer in the box that pops up, check the “End” box.
6. Snapping Tolerance There is a set radius around a location you snap to called the snapping tolerance. Within this distance a feature will automatically snap to that specific location. Outside that distance it will snap to another location or an error will pop up.
a. To change the snapping tolerance click the “Editor” and select “Options” in the drop down menu. b. Under the “General” tab, snapping tolerance is adjusted in the second box. A higher number means a further distance from the location you wish to snap to. A lower number means you will have a lesser distance.
7. Changing Line attributes After using the split tool the two line segments will still have the same attributes. You must manually change them.
a. In the “Editor” toolbar click the “Attributes button. b. Make the adjustments that apply to the new segment under “Value” using the drop down menus.
8. Tablet Used to add manual annotations to the map. Ex: Writing in notes or circling specific areas. Saint Saint Mary’s University – Pietersma - Perrott & van Proosdij Page 65
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a. Click “View”, “Toolbars”, Tablet”
b. To write something use the marker . For highlighting click . Use the eraser to erase specific parts, or delete for the entire drawing.
9. Camera a. Double click on “G-Camera” icon on the Desktop or press “F2” to open camera program.
b. Bottom Menu: -“Cam Switch” changes the camera view to take pictures in front of, or behind Yuma.
-“Macro” should be enabled when taking pictures up close.
-“GPS info” is enabled to have GPS coordinated saved with the picture you are taking. This is shown in orange text at the bottom of the display screen.
-Image size changes the image resolution.
c. Top Menu: The selected item will show in orange instead of white. -Camera: This will be selected automatically upon opening. To take a picture press the large green camera in the bottom left hand corner of the screen, or press the red button on the right side of Yuma.
-Video: Recording a video uses the same buttons as taking a picture.
-Photo Album: The “Play” button will show you your photo album, starting at the most recent picture. Scroll through using the left and right arrow buttons on the screen. “File information” on the bottom menu will allow you to enable or disable extra information about the picture (Time, date, image size, detailed GPS). If GPS is enabled from the camera mode is will still show up on the picture if “File Information” is disabled. To delete a photo simply scroll to it in the album and click the “Delete” button on the bottom menu.
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