Conifer Needle Chlorophyll Fluorescence, Niwot Ridge, Colorado, USA, 2017-2018

This dataset provides chlorophyll fluorescence measurements made on pine and spruce needle tissues at the Niwot Ridge AmeriFlux Core site (US-NR1) near Nederland, Colorado, USA, during the summers of 2017 and 2018. Two types of measurements were made using pulse-amplitude-modulation (PAM) fluorometry: the photosystem II (PSII) operating efficiency in the light (Fq'/Fm' at variable light levels), and the maximum quantum efficiency of PSII photochemistry (Fv/Fm) on dark-acclimated tissues. Chlorophyll fluorescence measurements were made to determine seasonality of photosynthetic performance at the needle level.

Data and Resources

Additional Info

Field Value
Maintainer Earthdata Forum
Last Updated August 25, 2026, 09:23 (UTC)
Created April 1, 2025, 15:16 (UTC)
accessLevel public
bureauCode {026:00}
catalog_conformsTo https://project-open-data.cio.gov/v1.1/schema
harvest_object_id e22170ec-7e81-4b57-8d4d-a165655cc1c9
harvest_source_id b99e41c6-fe79-4c19-bbc3-9b6c8111bfac
harvest_source_title Science Discovery Engine
identifier 10.3334/ORNLDAAC/1722
license https://www.usa.gov/government-works
modified 2026-08-17T22:16:01Z
programCode {026:000}
publisher ORNL_DAAC
resource-type Dataset
source_datajson_identifier true
source_hash 044a555c8e2c5d5e925fefd442bb33f01395319f8acff102cd4aa2ea607325dd
source_schema_version 1.1
spatial ["CARTESIAN", [{"WestBoundingCoordinate": -105.55, "NorthBoundingCoordinate": 40.03, "EastBoundingCoordinate": -105.55, "SouthBoundingCoordinate": 40.03}]]
temporal 2017-07-10/2018-06-11
theme {"Earth Science"}