Gyalsung viewshed


ISO 19115-3 Metadata

Metadata Information

Metadata identifier:
Identifier code: 315a8aeb20924d89b3977c972530b023
Default locale:
Language code: eng
Character encoding: utf8
Metadata contact:
Role: pointOfContact
Responsible party:
Organization:
Name: National Land Commission
Indvidual:
Individual:
Name: Jigme Namgay
Position name: Survey Engineer
Metadata date information:
Date type: revision
Date: 2026-02-25T00:00:00
Metadata standard:
Title: ISO 19115-3 Geographic Information - Metadata - Part 1: Fundamentals
Edition: 2014
Metadata scope:
Resource scope: dataset
Metadata maintenance:
Update frequency: asNeeded

Data Identification Information

Resource citation:
Title: Gyalsung viewshed
Citation date:
Date type: publication
Date: 2026-02-25T00:00:00
Citation date:
Date type: creation
Date: 2021-10-01T00:00:00
Online resource:
Online location: https://nsdi.systems.gov.bt/portal/sharing/rest//content/items/315a8aeb20924d89b3977c972530b023/data
Abstract: This dataset was created to identify and delineate green zone (no-construction) areas surrounding Gyalsung project sites in Bhutan in accordance with official directives to protect peaks, surrounding state land, and visually sensitive areas. Using viewshed analysis based on a Digital Elevation Model (DEM), the data maps areas visible within a 5 km radius from the Gyalsung boundaries and incorporates additional state land near international borders where applicable. The resulting green zone layer serves as a planning and regulatory tool to guide land-use decisions, prevent incompatible development, support environmental conservation, and ensure visual security and landscape protection around the Gyalsung sites.
Purpose: This data can be used for identifying green zones in Gyalsung project sites.
Status: completed
Point of contact:
Role: resourceProvider
Responsible party:
Organization:
Name: National Land Commission
Indvidual:
Individual:
Name: Lobzang Tobgye
Position name: Specialist
Themes or categories of the resource: boundaries, location, planningCadastre
Resource extent:
Geographic element:
Bounding rectangle:
West longitude: 91.136
East longitude: 91.2449
North latitude: 27.3008
South latitude: 27.2059
Resource maintenance:
Update frequency: asNeeded
Descriptive keywords:
Keywords: open

Resource constraints:
General Constraints:
Limitations of use: This data can only be used for gyalsung area
Default locale:
Language code: eng
Character encoding: utf8

Resource Lineage

Lineage scope:
Source:
Source description: 20m CI of 25K Digital Topographic map (DEM)
Process step:
Process description: The data processing began with the creation of sufficient observer points within each Gyalsung plot boundary to ensure adequate spatial coverage for visibility analysis. A Digital Elevation Model (DEM), generated from the 1:25,000 scale Digital Topographic Map using a 20 m contour interval (CI), was used as the primary elevation input for the analysis. A crow-flight distance of 5 km from each observer point was applied to generate the cumulative viewshed area. Finally, the overall visibility area (green zone) was derived by aggregating the smaller visible and non-visible portions within the computed viewshed area to produce a consolidated visibility output.

Distribution Information

Distribution format:
Format specification citation:
Title: Keyhole Markup Language
Edition: NA
Digital transfer options:
Online location:
Online location: https://nsdi.systems.gov.bt/portal/sharing/rest//content/items/315a8aeb20924d89b3977c972530b023/data