ADVANCED HIGHER GEOGRAPHY. Exam Preparation. Geographic Methods & Techniques. Fieldwork Skills

Transcription

1 ADVANCED HIGHER GEOGRAPHY Exam Preparation Geographic Methods & Techniques Fieldwork Skills

2 PHYSICAL FIELDWORK 2 Problems / Issues Processing Techniques 1. Coastal / Beach Sampling Measure width of beach from strand line to back of beach using a tape measure Using ranging poles to identify notable changes in beach slope Use ranging poles and a clinometer to measure angle of beach or alternatively use a Smartphone app placed on a metre stick to give angles Infiltration rates - use a stopwatch to time how quickly 1ltr of water (in a bottomless plastic bottle ) disappears Porosity rates - fill a 1ltr jug with sediment or sand and then add water to calculate the percentage of space between sand/pebbles Beach sediment (pebbles) should be sampled randomly (e.g. using a blindfold) and pebble axes can be measured using callipers and Callieux roundness cards Finer sediment can be measured using sediment sieves and the percentage of material collected in each sieve can be calculated once each layers is weighed Wave frequency can be measured by timing number of breaking waves to pass an object (e.g. ranging pole or offshore rock) in 1 minute Change in beach or cliff position over time can be analysed using historical maps (secondary sources from a local reference library) or historical photographs Awareness of tide timetables (in inaccessible locations) Beach profiles can vary considerably during the year (winter storms cause more erosion) - may need to repeat across various seasons Difficulties using a clinometer with ranging poles particularly in exposed/windy conditions Need to ensure pebbles are selected randomly to avoid human influence over selection - use a blindfold Beach transects / crosssections Divided bar graphs to show porosity and 5 of sediment type (especially sand grain sizes) Dispersion graphs for comparison of pebble sizes. Chi-square can be used to prove a difference in sediment type between two beaches Zingg analysis (graph) to show groupings of pebble sizes (rods, blades etc)

3 PHYSICAL FIELDWORK 3 2. River Studies Measure width using a tape measure Divide channel width by 11 to give 10 sections, measure the depth at each interval using a metre stick (regular sampling) Measure speed using a flowmeter or by timing a float (e.g. orange) to cover a specific distance (5 metres) Valley sides an be measured using a clinometer Wetted perimeter can be used by laying a chain along river bed or a programme (e.g. Geopacks) Sediment should be sampled randomly (e.g. using a blindfold) and pebble axes can be measured using callipers and Callieux roundness cards 2. Soil Sampling Soil augur can show distinct layers of soil (profile) or dig a small pit and take photographs Soil texture can be sampled using roll test and flow chart helps determine if the soil is clay, loam, sandy etc. ph can be indentified using a ph meter or taking sample and testing with ph paper or universal indicator (distilled water added oil sample) Organic content can be obtained by weighing soil sample, then drying in a cool oven for 24 hours. Soils sample can be burned to remove all humus and then weighed. % of organic, mineral and water can be calculated. Inaccessible and overgrown sample sites Rate of flow (flood conditions) can make sampling dangerous Differences in flow rates across a meander (deeper on outside of bend) Low volumes of water can create difficulties in measuring velocity (need to repeat and average) Gain permission of landowner before digging soil samples Ensure probes for ph and soil moisture metres are clean before use River cross section shows relationship between depth and width Scatter graphs can be used to compare different points on a river e.g. relationship between distance from source and discharge. Further statistical analysis (correlations) using Spearman Rank or Pearson's Product tests. Dispersion graphs for comparison. Zingg analysis (graph) to show groupings of pebble sizes (rods, blades etc) Annotated photographs or sketches of soil profile Triangular graphs to show 3 variables of soil structure (organic, inorganic and water)

4 PHYSICAL FIELDWORK 4 4. Sand Dune / Vegetation Studies Similar processes to beach transects - use ranging poles and clinometers to measure angles across a dune system Quadrats used to measure vegetation covers e.g. % of bare sand and % of different species Soil moisture, light and ph meters can be used Plant guides or keys used to determine species of flowers and grasses Organic material (humus) use same procedures for measuring organic content in soils (dry, weigh and burn off humus) 5. Microclimate Studies Use a hand-held thermoanemometer at various points within a town or neighbourhood Hygrometer to measure humidity Cloud cover and visibility could be observed Difficult to identify plants using guidebooks (esp. in winter months) Ensure probes for ph and soil moisture metres are clean before use Light meters can give varying results (even slight shadows can affect results) Soils samples should be handled with rubber gloves and sterilised before being processed (can contain harmful bacteria) Need access to a fume cupboard when burning humus in soils Wind strength is hard to measure at ground level The Beaufort scale is subjective Cloud cover can change from one moment to the next, affecting temperature and light readings. Need to repeat and average constantly Observations (cloud cover) are subjective Kite diagrams show change in vegetation across a dune system or slope Triangular graphs to show 3 variables of soil structure (organic, inorganic and water) Spearman's Rank Correlation Coefficient to investigate changes with distance inland from the seashore Simpson s diversity index can show the range of plants within an area Wind rose / polar graph can show weather Isoline maps to show patterns of humidity and temperature (isotherms) Annotated base maps

5 HUMAN FIELDWORK 5 1. CBD Studies Main services can be used by annotating a large scale base map (e.g. 1:2,000) using a RICEPOTS system of land use Shopping questionnaires (how often do you visit / where do you come from / method of travel and other questions regarding the quality of services) are very useful for determining the sphere of influence of a town Rateable values of properties can be obtained using secondary sources (e.g. Scottish Assessors website). This can help define the PLVI of a town centre Pedestrian and traffic counts taken at numerous points can help ascertain foot flow in the CBD Count storeys of buildings and annotate a base map 2. Environmental Quality Evaluate a number of points against a key set of criteria (e.g. building condition, noise, litter, gardens, traffic levels etc) and scoring them e..g 1 = low, 5 = high. Totals can then be determined Can be difficult to determine usage of upper floors in the CBD Timing of traffic / pedestrian counts. One off counts can provide misleading trends e.g. Weekend v midweek (better to repeat and average) Results produced can be subjective (may need to repeat and average) May need to take lots of samples Time of day can also be important (e.g. traffic/litter) Annotated / coloured land use map Nearest Neighbour can be used to show if clustering of certain services (e.g. pubs, vacant properties) exist Flow line maps show pedestrian and traffic movements Bipolar tables/graph can process questionnaire results to show perception of an area Simpson s diversity index can show the range of shops within an area / CBD based on RICEPOTs analysis Isoline map can show places of the same environmental quality Bipolar tables/graphs can be used to compare different areas

6 HUMAN FIELDWORK 6 3. Village & Neighbourhood Studies Traffic counts (am and pm) can help determine movements of commuters Service and housing surveys using RICEPOTS system to label a map e.g. Secondary sources e.g. Scottish Neighbourhood Survey can provide information of population structure, crime, jobs Historical house price sales from estate agents websites e.g. Rightmove.com Environmental quality survey (see No.2 on page 5) 4. Farm Study Rural land use mapping - annotate a base map with main crops and livestock Interview farmer /farm workers on land use decisions. Farmer may be able to provide detailed maps (fertiliser use, soil nutrient levels) Historical maps can show land use changes and changes in field boundaries 5. Industry / Tourism Study Interview site owner and workers on main decisions. Hotel owners - details on occupancy rates Tourism questionnaires Historical maps can show land use changes over time Secondary sources e.g. CAA Aviation Authority have historical data on passenger numbers, (airport study); local council or Scottish Tourist Board may also have data Ensure traffic counts are repeated and averaged EQS can be fairly subjective Gain permission of farmer before undertaking fieldwork Land use can vary between seasons (crop rotation/ dual cropping) Gain permission of landowner before undertaking fieldwork or taking photos Annotated land use map Population pyramids using Chi-square to show differences between 2 villages or neighbourhoods (grouped data) Isoline maps for environmental quality and house price sales Annotated land use map (crop types) Bar/line graphs show productivity or employee numbers over time Annotated land use map Bar/line graphs show productivity or employee numbers over time Bipolar analysis (perception/quality of tourist facilities)

7 HUMAN FIELDWORK 6. Pollution Studies Analyse air samples using test tubes with filter paper located randomly around an area (leave out for 2-3 weeks then collect) Secondary sources of air pollution (e.g. Nitrogen oxide levels, particulates) from SEPA website and local authority data Observe lichen coverage on walls and trees as an indicator of atmospheric pollution (some lichens are more tolerant of pollutants) Noise pollution can be measured using a noise or decibel metre Thermal pollution of water measured using a thermometer ph of a river/stream using a ph meter Observe invertebrates on stream bed e.g. Mayfly nymph (indicator species) can indicate how well oxygenated a stream is Air samples will vary during the year and with different weather conditions (e.g. air quality is poorer during anticyclones) Presence or absence of lichens on a tree/wall may indicate a very small scale air pollutant (atypical of across an area) Fluctuations through the day in noise (traffic, transport, building works) may have to use numerous samples at various times to achieve a baseline Similar to problems of taking river samples Isoline map of atmospheric pollution levels Bar graphs and line graphs allow comparisons to be made between locations and over time Isoline map connecting places of the same decibel levels Annotated maps

8 RELAIBILITY AND VALIDITY 8 Improving Reliability In order to improve the overall reliability of results, improve consistency and reduce the impact of anomalies and strengthen our conclusions a number of strategies can be followed: Ensure the sample is representative of the whole population e.g. use blindfolds when random sampling pebbles Repeat fieldwork at another time - the environment (e.g. beaches, sand dunes, rivers) changes throughout the year and traffic and pedestrian counts vary during the day and across the week Do more samples or transects or spread them further apart to come to genuine conclusions Take averages Improving Validity of Procedures The concept of reliability is that any significant results must be more than a one-off finding and be inherently repeatable. Essentially this means only changing one variable when undertaking fieldwork to improve the accuracy of results. This could involve: Using the same equipment or apparatus e.g. same size of quadrat, same flow meter, light meter for all samples taken The equipment has been properly calibrated Ensuring all other variables are kept constant (if possible) e.g. Same time of day or same stage in a tidal cycle allows valid comparisons to be made The relationship between reliability and validity can be confusing because measurements can be reliable without being valid. However, they cannot be valid unless they are reliable.