CZOs are building an infrastructure that enables measurement of Critical Zone evolution, structure, and processes. A key goal is to construct whole-watershed energy, water, carbon and other mass balances for a variety of environmental settings.
The Susquehanna-Shale Hills, Southern Sierra, and Boulder Creek CZOs were funded originally in 2007, with the Luquillo, Christina River Basin, and Jemez River Basin/Santa Catalina Mountains CZOs being funded in 2009. Four more CZOs were funded in 2013 and include the Reynolds Creek, Eel River, Calhoun Forest, and Intensively Managed Landscape CZOs. Find a summary of CZO site characteristics in the CZO Attributes Table (PDF).
Each CZO has its own unique sets of questions, hypotheses, and experimental designs. However, the CZO network of sites is being shaped by working groups, emergent common questions/hypotheses, X-CZO campaigns, activities or modeling, the national office, and, as discussed here, a suite of common measurements. These efforts seek to make the CZO network greater than the sum of its parts.
The CZOs are sites where innovative techniques are being developed and tested for quantifying Critical Zone (CZ) processes and services. While each site develops its own novel approaches, all sites aim to make a set of comparable measurements across CZOs, as well as with other local, regional, and global monitoring efforts.
The goal of each site and the network is to develop fully the infrastructure and personnel needed to:
1. CZ structure and evolution; including 3D spatial distribution and characterization of bedrock, soil, water, vegetation, and topography; regolith and drainage valley evolution; rates of soil production, differentiation, erosion, and deposition.
2. Event-based and continuous fluxes across CZ interfaces; including bedrock-soil; soil-atmosphere; soil- vegetation; vegetation-atmosphere; landscape surface-soil-water.
3. Changes in storage (i.e., budgets) of major CZ reservoirs at the catchment scale;
The CZO network uses both innovative instrumentation and campaign-style measurements to quantify the composition and fluxes of energy, water, and solutes and sediments at different spatial (e.g., plot to watershed) and temporal (event to millennial) scales across the land-atmosphere interface, through the vegetation and microbiota and in the regolith (soil, saprolite, and porous/fractured bedrock) and stream water. A representative set of measurements/approaches is discussed below.
To view the matrix, see the last page of the PDF Version ("Common Critical Zone Observatory Infrastructure and Measurements").
Following the October 2013 meeting in Arlington, VA, CZO PIs contributed to the development of a “Common Measurements Matrix” that shows those measurements being conducted at the CZOs (see table on the following pages). The idea for this matrix originated from the CZO network Graduate Research Group.
In this matrix:
X indicates instrumentation is currently in place or sampling is occurring, owned and operated by the CZO; Y indicates instrumentation is currently in place, owned and operated by a partner of the CZO (see comments);
Z indicates that it is planned to be installed or implemented in the future by the CZO.
The original Excel file also includes comments in individual cells pertaining to specific issues flagged for a given CZO by the PI (e.g., identification of partners, etc.).
The matrix highlights the commonality of several types of measurements occurring at all CZOs, some of which are collected in collaboration with partnering agencies or projects.
This matrix remains under construction. Our goal is to have it be an active spreadsheet that links directly (by clicking on a given cell) to the infrastructure maps for a given CZO and shows the sensor, sampler and/or sample collection array that pertains to a given set of measurements. By doing so, the density or frequency of such measurements will be available to users in a hierarchical fashion.
It is important to note that although there is strong correspondence in the targets of the measurements at the CZOs, the different CZOs are not using the same techniques in all cases. This represents an opportunity to share information on benefits and shortcomings of particular methods (e.g., techniques for soil moisture quantification, carbon flux, etc.).
Future cross-CZO efforts on Common Measurements will focus on sharing technology and experience to highlight the benefits/shortcomings of various measurement protocols being employed. In addition, the linkage of the CZO Common Measurements Matrix to CZO-specific data sets and maps will be established.
Common Measurements sub-groups are currently being developed to share methodologies and develop common protocols pertaining to laboratory-based analytical techniques. Potential subgroups include (i) physical separations, sample preparation, archiving and preservation; (ii) soil and aquatic microbiology; (iii) organic geochemistry; (iv) inorganic geochemistry; (v) hydrochemistry; and (iv) organic matter dynamics.
CZO common measurements white paper 2015
(244 KB pdf)