Relations between Retired Agricultural Land, Water Quality, and Aquatic‐Community Health, Minnesota River Basin

Abstract

The relative importance of agricultural land retirement on water quality and aquatic-community health was investigated in the Minnesota River Basin. Eighty-two sites, with drainage areas ranging from 4.3 to 2200 km, were examined for nutrient concentrations, measures of aquatic-community health (e.g., fish index of biotic integrity [IBI] scores), and environmental factors (e.g., drainage area and amount of agricultural land retirement). The relation of proximity of agricultural land retirement to the stream was determined by calculating the land retirement percent in various riparian zones. Spearman's rho results indicated that IBI score was not correlated to the percentage of agricultural land retirement at the basin scale ( = 0.070); however, IBI score was correlated to retired land percentage in the 50- to 400-m riparian zones surrounding the streams ( < 0.05), indicating that riparian agricultural land retirement may have more influence on aquatic-community health than does agricultural land retirement in upland areas. Multivariate analysis of covariance and analysis of covariance models indicated that other environmental factors (such as drainage area and lacustrine and palustrine features) commonly were correlated to aquatic-community health measures, as were in-stream factors (standard deviation of water depth and substrate type). These results indicate that although agricultural land retirement is significantly related to fish communities as measured by the IBI scores, a combination of basin, riparian, and in-stream factors act together to influence IBI scores.

A Fish-Based Index of Biotic Integrity for the Assessment of Streams Located in a Sugarcane-Dominated Landscape in Southeastern Brazil

“…This indicates some variability in the biological integrity within sugarcane reaches, which seems to be related to the intensity of the agricultural activity being performed. A similar situation was observed in Minnesota streams by Christensen et al (2012), who showed that when agricultural land retirement was concentrated near the stream, a positive effect on selected water quality measurements and aquatic-community health occurred. Although it would be desirable that study sites were widely distributed over the basins few sites fitted into the selection requirements.…”

“…Strong relationships between IBI scores and measures of urbanization, forest cover, riparian forest cover, agriculture and water quality (Hued and Bistoni 2005;Pinto et al 2006;Christensen et al 2012) have been found, which indicates that land use in the watershed has a strong effect on habitat quality and the biotic integrity of streams. The IBI reflects the responses of fish communities to environmental changes, both for single impact factors as well as the cumulative effects of multiple changes in the watershed (Hering et al 2006).…”

Water Quality Assessment Based on CWQI and NDWI Indices in Mariout Lake, Egypt

“…This highly related to the huge number of human activities nearby. Major source of river water pollution comes from domestic sewage, animal waste, agricultural waste, soil erosion and runoff from the settlement [17]. EEAA quality standards, nitrate content has to be ≤0.1 mg/l, Station 3 recorded low Nitrate (0.01), and station 4 recorded high Nitrate (3.66).…”

Water Quality Status of Ciambulawung River, Banten Province, Based on Pollution Index and NSF-WQI

“…This highly related to the small number of human activities nearby. Major source of river water pollution comes from domestic sewage, animal waste, agricultural waste, soil erosion and runoff from the settlement [21]. GR No.…”