Tower-based camera systems are a great way to get ground-based data about plant growth. These types of data help researchers bridge the gap between ground and satellite sampling.
Since 2007, TimeScience has worked closely with Dr. Pamela Nagler of the USGS in Arizona and Dr. Kevin Hultine of Northern Arizona University to document the impact of a bio-control agent, the salt cedar leaf beetle (Diorhabda carinulata) on invasive salt cedar (Tamarix spp). As part of this project, TimeScience installed multiple high resolution, wireless camera systems and infrared cameras at the University of Utah’s Rio Mesa field station in northeastern Utah. Camera images are uploaded of a satellite Internet connection permitting the USGS to monitor beetle and tamarisk impacts on riparian ecology and water usage in real time [Map of tower locations]. All data from this projects is uploaded to the Rio Mesa servers where it can be viewed in near realtime using TimeScience’s interactive TimeGraph software.
There are two primary camera sites at the Rio Mesa Field station. At both sites cameras have been installed on 35’ towers recording images throughout the growing season since 2008. Tower one is known as the “Orchard” site and tower two is known as the “Gauge” site.
Both towers have a nadir (down-facing) 5 megapixel (MP) network camera (Stardot, Netcam SC) and one or two infrared 3.1 MP “crop” cameras (TetraCam, ADC Sentry) recording phenology in mature tamarisk stands (Map, sites 2, 3). An additional north‑facing 5MP camera on the southern tower (Map, site 3) records a wide-angle view of about half of the valley, including the tamarisk stands surrounding both towers (Map, site 3). The tower cameras have been recording high resolution JPEG images at 15 minute intervals, 4-8 hours a day since May, 2008. Total visible light images recorded 2008 through 2010 is about 12,000 per camera, 36,000 totals. Each infrared camera records an image every hour at 11, 12, 13, 14 hrs (4 images per day total). An additional lower resolution surveillance camera records a Southeast facing view of the entire valley at 5 minute intervals 16 hrs a day from ridge at the Northwest corner of the ranch (Fig. 1, site 1). The camera towers are each located within stands of tamarisk that are instrumented with sap flux sensors recording water usage in a total of 29 tamarisk trees. Four Freemont Cottonwood trees in this area are also instrumented with sap flux sensors. Sensors at each tower also record temperature, humidity, vapor pressure deficit (VPD), soil moisture and open canopy soil moisture. Two additional weather stations on the property record temperature, humidity, VPD, wind speed, wind direction, solar radiation and soil temperature at four depths (Map, sites 4, 5).
All image and weather sensor data is retrieved over the field station’s 802.11 wireless network and archived on a desktop computer at the Rio Mesa ranch. These data are then uploaded to the project’s central data server hosted at theUniversityofUtah. Uploaded data is immediately available for public viewing through the TimeGraph data visualization tools (TimeScience, 2008). The TimeGraph system enables users to co-visualize current and historical image and sensor data from any tower or weather station location in an interactive format.
Visible and infrared camera data is analyzed with data from co-located sap flux sensors in individual Tamarisk and Cottonwood trees and other sensor data to permit ground-truthing of matching data from the MODIS and ASTER satellites.
This spring, in addition to continuing the research at Rio Mesa, TimeScience will be installing additional camera systems at a remote tower site north of Lake Mead. At this site we will install multiple megapixel visible and infrared cameras as well as one of our Gigavision cameras. The Gigavision camera will stream billion-pixel resolution time-lapse images to the web in near real time over a cellular Internet connection. These camera systems will help document the impact of the beetle on endangered Willow flycatcher habitat in the Virgin River basin.
Online images, timelapse movies and data downloads can be found here:
Here’s an example of the type of image data we get using visible and Infrared cameras:
More photos here
- Nagler, P.L., Brown, T. (In review). Monitoring impacts of Tamarix leaf beetles (Diorhabda carinulata) on the leaf phenology and water use of Tamarix spp. using ground and remote sensing methods.
- Nagler, P.L., Brown, T. et al. 2010. Monitoring impacts of Tamarix leaf beetles (Diorhabda elongata) on the leaf phenology and water use of Tamarix spp. using ground and remote sensing methods. American Geophysical Union Annual Meeting. 2010, AGU:San Francisco.
- Nagler, P.L., Brown, T. et al. 2009. Using webcam technology for measuring and scaling phenology of tamarisk (tamarix ramosissima) infested with the biocontrol beetle (diorhabda carinulata) on the Dolores river,Utah, in American Geophysical Union Annual Meeting. 2009, AGU:San Francisco.