Article written by Joseph Okotto-Okotto
Numerous methods exist for quantifying mismanaged waste in the environment. One such method which is rapidly gaining scientific acceptance is the use of Transect Surveys. For decades, Transect Surveys have been used to shed light and provide insights that help scientists to understand the characteristics of complex natural environments. A transect is a scientific method of investigating or surveying a sequence of micro-environments by conducting a sampling exercise in randomly selected geographical cross-sections of a given environment. In several scientific disciplines, it is usually a straight line that cuts through a natural landscape and is deemed to be representative of that particular landscape that is to be studied.
When carrying out a transect survey, a straight line that cuts through the landscape is therefore established and placed on the landscape so that observations and measurements can be made along that line in a standardized way. The line is to be long enough and properly oriented in a randomized way to capture the variation in the area of interest. Samples are taken at regular intervals along the transect line and data from such samples are recorded and analyzed to identify patterns and trends. The United Nations Environment Programme have developed guidelines for using transect surveys to monitor marine litter washed up on beaches.
Transect survey
Transect walks
In plant ecology, transect surveys are largely conducted using a measuring tape to mark out the transect line quadrats to sample the subjects of the survey, and Global Positioning Systems (GPS) to record the locations of the transect line and survey plant species growing within quadrats. In other fields such as marine ecology, a transect line and SCUBA diving equipment are often used to survey seabed ecology. Community groups and planners have developed a similar observational approach for urban environments, known as a neighbourhood or street audit, where systematic observations can be made about hazards or amenities. However, despite urban environments, particularly ‘off-grid’ neighbourhoods lacking services being sources of mismanaged waste, litter transect surveys have seldom been adapted to the urban environment.
As a means of supporting the attainment of target 12.4 of the United Nations’ Sustainable Development Goals (which aims to achieve the environmentally sound management of chemicals and all wastes throughout their life cycle), the project adapted a beach litter transect survey protocol and used it to quantify mismanaged waste in Kisumu and Greater Accra. For those interested in using the transect survey method elsewhere, a recording form is available here. The tool was developed through a rigorous process that involved technical discussions, field testing and protocol refinements.
Nonetheless, we still feel there is scope for further refinement. We carried out our fieldwork in the midst of the pandemic, so to protect the health of the project field team, we only observed waste, but did not pick items of discarded waste up and weigh them. Our protocol could be further adapted so that teams pick up discarded waste and weigh it afterwards, then return to the same transects again at a later date to repeat the process. Our survey team also counted scattered waste items every 50 paces, so it is important for team members to practice pacing and have a ‘pace factor’ that adjusts for different team members’ shorter or longer stride lengths.
Transect Survey Form for Solid Waste Quantification
