Assessment of the accuracy of profile available water and potential rooting depth estimates held within New Zealand’s fundamental soil layers geo-database
2015
Pearse, Grant | Moltchanova, Elena | Bloomberg, Mark
The Fundamental Soil Layers (FSL) serve historically as New Zealand’s primary source of soil information. They contain a range of New Zealand’s soil attribute information held in a spatial database. Despite their wide use in a range of applications, few direct assessments of the accuracy of FSL attribute information have been undertaken to date. This study aims to provide an assessment of the accuracy of the FSL by comparing observed data for Profile Available Water (PAW) and Potential Rooting Depth (PRD) with FSL estimates for these two attributes. Two datasets were used to conduct the tests. The first dataset (n=35) contained measured observations for PAW and PRD. A second dataset (n=173) contained measured observations for PRD only. A regression model found a weak relationship between measured values and FSL estimates for PAW and PRD (correlations ranged from –0.08 to 0.17). Additional FSL estimates provided in the form of class intervals were tested by calculating the proportion of observed values within the specified FSL class interval. The effect of estimate lineage (underlying data and estimation method) on the accuracy of the class intervals was assessed using a logistic regression. Overall the FSL estimates for PRD and PAW were inaccurate, and allowance for data lineage did not improve the accuracy of the FSL estimates.
Show more [+] Less [-]AGROVOC Keywords
Bibliographic information
This bibliographic record has been provided by National Agricultural Library