Development and application of an agricultural intensity index to invertebrate and algal metrics from streams at two scales

Waite, IR

HERO ID

3355031

Reference Type

Technical Report

Year

2013

Language

English

HERO ID 3355031
Year 2013
Title Development and application of an agricultural intensity index to invertebrate and algal metrics from streams at two scales
Authors Waite, IR
Publisher Text Wiley-Blackwell
City Hoboken, New Jersey
Volume 49
Page Numbers 431-448
Abstract Research was conducted at 28-30 sites within eight study areas across the United States along a gradient of nutrient enrichment/agricultural land use between 2003 and 2007. Objectives were to test the application of an agricultural intensity index (AG-Index) and compare among various invertebrate and algal metrics to determine indicators of nutrient enrichment nationally and within three regions. The agricultural index was based on total nitrogen and phosphorus input to the watershed, percent watershed agriculture, and percent riparian agriculture. Among data sources, agriculture within riparian zone showed significant differences among values generated from remote sensing or from higher resolution orthophotography; median values dropped significantly when estimated by orthophotography. Percent agriculture in the watershed consistently had lower correlations to invertebrate and algal metrics than the developed AG-Index across all regions. Percent agriculture showed fewer pairwise comparisons that were significant than the same comparisons using the AG-Index. Highest correlations to the AG-Index regionally were 0.75 for Ephemeroptera, Plecoptera, and Trichoptera richness (EPTR) and 0.70 for algae Observed/Expected (O/E), nationally the highest was 0.43 for EPTR vs. total nitrogen and 0.62 for algae O/E vs. AG-Index. Results suggest that analysis of metrics at national scale can often detect large differences in disturbance, but more detail and specificity is obtained by analyzing data at regional scales.
Doi 10.1111/jawr.12032
Wosid WOS:000317001700013
Report Number JAWRA-12-0141-P
Is Certified Translation No
Dupe Override No
Comments Funded by USGS
Is Public Yes
Language Text English
Keyword agricultural intensity index; macroinvertebrate and algal indicators; national and regional scales; riparian assessment
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