Question

Which survey technique utilizes aerial or satellite imagery to gather information about land use, vegetation and other features of the Earth's surface?

• A. Field survey
• B. Remote sensing
• C. Participant observation
• D. Interview survey

Hint:

(x) \textbf{Remote Sensing:} Acquiring information about an object or phenomenon without making physical contact, typically using sensors on satellites or aircraft to detect and record electromagnetic radiation reflected or emitted from the Earth's surface.
(y) \textbf{Aerial photography} and \textbf{satellite imagery} are key products of remote sensing.
(z) Used extensively for mapping land use/land cover, monitoring vegetation, environmental assessment, disaster management, etc.
({) Field survey is ground-based. Participant observation and interview surveys are social science research methods.

Answer 1

The Correct Option is B

The question describes a survey technique that uses imagery from aircraft or satellites. Let's analyze the options:

• Option (a): Field survey (Ground survey) 

This involves direct observation, measurement, and data collection on the ground at the site or area of interest. Examples include land surveying with theodolites or total stations, ecological quadrat studies, and soil sampling. While field surveys may use aerial or satellite imagery for guidance, they do not primarily rely on it for data collection. Therefore, this option does not match the description.

• Option (b): Remote sensing

This is the science and art of acquiring information about the Earth's surface (or other objects) without being in direct physical contact with it. Remote sensing typically involves the use of sensors on airborne platforms (such as aircraft or drones) or spaceborne platforms (satellites) to gather data, which is often in the form of images. These images, such as aerial photographs and satellite imagery, are then analyzed to gather information about land use, land cover, vegetation, topography, water bodies, and other features. This description perfectly matches the question, making this the correct answer.

• Option (c): Participant observation

This is a qualitative research method used in social sciences, particularly in anthropology and sociology, where the researcher immerses themselves in a social setting to observe behavior and interactions from an "insider" perspective. This method is unrelated to aerial or satellite imagery for surveying Earth's surface features. Therefore, this option is incorrect.

• Option (d): Interview survey (or Questionnaire survey) 

This involves gathering data through direct questions to individuals or groups, either face-to-face, by phone, or via written questionnaires. It is primarily used for collecting opinions, attitudes, and demographic data. It does not rely on aerial or satellite imagery for its data collection. Thus, this option is also incorrect.

Conclusion:

The survey technique that utilizes aerial or satellite imagery to gather information about the Earth's surface is Remote Sensing. This is the most appropriate choice as it aligns perfectly with the description given in the question.

Answer:

Option (b): Remote sensing