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Investigating pollution

Aims

  • To investigate lichen species distribution as bio-indicators of air pollution

  • To study the impact of quarrying, industrial activity or agricultural activity

  • To investigate patterns of air and noise pollution around a site (including decay with distance from the source) and to identify high impact areas

  • To relate levels of air and noise pollution to other data, for example population distribution and quality of life

  • To conduct studies before and after an event, for example the construction of a new bypass, road widening, traffic calming or a one off event such as a festival or sporting activity

  • To compare pollution levels in urban and rural areas

  • To relate pollution data to weather conditions, for example the prevailing wind direction

  • To examine management strategies for reducing pollution, for example noise reduction barriers, fencing or cuttings

Measuring air-borne particles

Using a rain gauge or bottle

  1. Place a funnel in the top of the rain gauge or bottle with filter paper in it

  2. Leave in pre-determined sites for a set period of time, when rainfall is predicted

  3. Collect following rainfall event and record the volume of water

  4. Remove and dry the contents of the filter paper in a hot oven

  5. Weigh the particulate on sensitive scales and record the mass per given volume of precipitation for each site

  6. Use a microscope to examine the composition of the particulate

  7. Repeat the experiment to obtain averages, adding accuracy to the study

Using sticky tape

  1. Decide on a sampling strategy

  2. Attach pieces of double sided sticky tape around stakes or telegraph poles, lamp posts or trees (above the height of being easily reached) and remove the cover to expose the sticky surface of the tape

  3. Leave for a set period of time before removing the tape and examining under a microscope to compare the particulate build up

  4. To examine changes in particulate build-up over time, several strips can be mounted on card attached to a stake and left out. Each day one strip is uncovered, with the last being removed when the card is collected in (the control). The particulate can then be examined, and different sites compared

Using lichens as bio-indicators

  1. Before the study is undertaken, it is necessary to research lichen species and their habitats to determine which species are likely to be found on different surfaces, and which species are more or less tolerant to pollution

  2. Sites should be chosen which provide good contrast, for example:

    • An area close to heavy traffic or intensively fertilised farmland or cattle sheds

    • Areas with little disturbance, for example the edge of woodland, parkland, churchyards

  3. A sampling strategy should be devised which identifies trees to survey

  4. Then:

    • Survey at least three tree trunks of the same species at each site

    • Survey at least 10 twigs (3-4 cm diameter at the base) from the edge of the canopy (non-shaded). These can be from the same tree or from more than one of the same species

  5. All data should be clearly and accurately recorded

Studying noise pollution

  • A decibel meter gives accurate and sensitive readings, or alternatively, crude judgements can be made using a written scale (developed or obtained)

  • Readings can be taken at different times of day, during different levels of activity (during blasting, or rush hour on a busy road), at different sites, and with distance from the source

  • The data collected can be related to information gathered from questionnaires on resident's perceptions of the noise problem

Considerations and possible limitations

  • The sampling strategy selected should be carefully considered to ensure viable coverage of the area

  • Access may be an issue if land is privately owned

  • Equipment needs to be sensitive, for example scales for measuring particulates, DB meter

  • The wind strength and direction will have an influence on noise levels and the passage of air borne pollution, and should be taken into consideration

  • If it is not possible to obtain a decibel meter to record noise levels, judgements of noise can be crude and subjective

Carrying out an Environmental Impact Assessment

Introduction and aims

An Environmental Impact Assessment (EIA) is a type of audit, undertaken to systematically identify and analyse the likely impacts of a proposed development or project. Companies and developers must carry out an EIA and produce an Environmental Statement for their proposals.

An EIA can be a useful tool for examining local developments, projects or issues where there are potential ‘conflicts' between different users.

Project ideas

An EIA into a proposed development or project, for example:

  • A new housing estate

  • A new supermarket

  • A new retail, leisure or industrial park

  • A changing road system

  • The removal of hedgerows

  • Mining or quarrying activity

  • A new amenity or the relocation of an existing amenity, for example a football stadium

  • Changing conservation practices

An EIA of an existing project or an existing development site.

Equipment

  • Digital camera

  • Field sketching materials

  • Secondary data on proposed development, project or issue

  • Prepared environmental impact matrix

  • Impact checklist

  • Questionnaires

  • Other record sheets, for example noise pollution

Methodology

  1. Research and gather secondary data regarding the proposed development, project or issue

  2. Interview key people involved, for example the developer, manager or owner of the site or a member of the local council

  3. Sketch and photograph the site to identify the main features - if possible compare these to historical maps and photographs showing the original condition and use of the site

  4. Develop an impact checklist of all of the possible impacts that the project might have

  5. Develop and complete an impact matrix to visually represent the level of the potential impacts. The matrix should include factors relevant to the development or proposal you are investigating

  6. Conduct questionnaires to assess the views of local residents about the proposal. This can be carried out on a stratified basis to examine opinions by age, gender, race, income group or ethnicity

  7. Research the steps being taken by the development company or local council to address the issues of local residents and reduce the environmental impact of the project

  8. Analyse the potential impacts of the development project in light of the methods to reduce them, and reach conclusions about the levels of impact and disruption likely to be caused. Make proposals for further management

Considerations and possible limitations

  • Secondary data may be sensitive and therefore hard to obtain. Similarly, it may be difficult to arrange interviews with developers

  • Stratified questionnaire sampling can be hard to achieve in reality

  • There is a subjectivity risk with completing the impact matrix. Asking a few different people to complete the matrix and then averaging results may improve the accuracy of the results

  • A firm focus should be maintained within the investigation - devise a firm, direct question, hypothesis or statement as a title

Judgement surveys and environmental evaluation surveys

Introduction and aims

We naturally form opinions and make judgements about every day issues and situations which surround or affect us. Your investigation will often involve making your own judgements or gaining other people's perceptions and judgements about an issue. This can be the focus of the investigation, or act as supporting evidence, and may involve:

  • Conducting landscape evaluations to assess the likely impact of something

  • Assessing people's reactions to and opinions about a certain issue

  • Examining the degree of opposition to a particular development or project

  • Conducting residential investigations where different areas of a town or city are contrasted and compared

  • Examining people's opinions about different management strategies

  • Investigating the quality of an amenity, for example a community amenity like a park or a tourist amenity like a beach

  • Investigating the quality and suitability of service provision, for example car parking facilities

  • Using mental maps to assess people's perceptions of a place

Equipment

  • Prepared survey sheets, for example landscape evaluation, adjectival pairs, bi-polar surveys or agreement scales

  • Base maps of the area

  • Digital camera and sketching materials

Methodology

Landscape evaluation and quality surveys

  • Decide on the criteria for the survey, and the scoring or ranking system you will use. For example, a scoring system of zero to five, where zero = inadequate, one = satisfactory, two = fair, three = good, four = very good and five = excellent. Or, you could have a different scoring system for each set of criteria, with weighting depending on how important you consider the criteria to be. For example, the value of an important factor could be multiplied by 10

  • Decide on the sampling strategy and identify the sites. Mark these on a base map of the area, and also label any other significant and relevant features

  • Decide whether you are going to complete the evaluation yourself at each site, or distribute it to different user groups to complete. You may want to compare people's opinions by, for example, age or gender

Bi-polar surveys

Adjectival pairs:

  • Opposite adjectives are chosen and written down - some should be fact based, for examples historical and modern. Others should be value based, for example ugly and attractive

  • Different users can be asked to place a cross on a line between the pairs of adjectives, or assign a score for a particular variable

​Detailed bi-polar analysis

  • Build up a good personal knowledge of the area prior to your fieldwork in order to develop relevant and detailed criteria for the survey

  • The scale for the bi-polar survey should be decided and the record sheets developed

  • Visit and study each site and allocate scores systematically for each criterion. It helps to share the work amongst a group of people as it saves time and reduces bias

  •  ‘Half' scores are possible if it is decided that the score should be between two categories

  • Notes, photos and sketches can be used to support the judgements given

4. Perception/attitude surveys

  • Decide on a sampling strategy for your investigation. If you are interested in differences of opinion between people of different ages, genders or ethnicities you may consider using a stratified sampling technique

  • Develop the questions or statements for the survey - these can be the same or similar to those used for environmental quality surveys and an agreement scale 

  • Different users of the facility could also be presented with a base map of the site and asked to annotate with major land marks or features, positive and negative aspects

Considerations and possible limitations

  • Using closed questions or categories for the scale will quantify judgements, aiding statistical analysis

  • It's hard to assign real scientific value to judgement surveys as they are, after all, just people's opinions shaped by experience, age, gender, peer and family views, cultural background and upbringing

  • Subjectivity is unavoidable, but there are ways of reducing it and therefore increasing validity

  • Weighting more important criteria by multiplying or dividing the scores given. Scores can also be split, if they do not clearly fall into one category or another

  • Cover as wide a range of criteria as possible, and give detailed descriptions of each criterion to improve accuracy

  • Put personal views aside

  • The scoring system should be carefully thought through and developed; each person carrying out the survey must be fully confident with how it should be applied - carrying out pilot surveys as a group or looking at photographs and scoring them will improve the accuracy of the study

  • The sites must be representative of the area as a whole, and pilot surveys should be conducted to identify representative sites

  • When surveying multiple sites it may still be hard to develop a scoring system or set of criteria which are applicable to every site