Dr. Edwards et al., EFFECT OF BMP IMPLEMENTATION ON STORM FLOW QUALITY OF 2 NORTHWESTERN ARKANSAS STREAMS, Transactions of the ASAE, 40(5), 1997, pp. 1311-1319
The effectiveness of management practices in improving quality of runo
ff from agricultural land areas has been reported based primarily on r
esults from plot-and field-scale studies. There is limited information
available on watershed scales, particularly when the dominant agricul
tural land use is pasture. The objective of this study was to determin
e whether a program of Best Management Practice (BMP) implementation i
n the Lincoln Lake watershed of northwestern Arkansas was effective in
reducing storm streamflow concentrations and mass transport of nitrat
e nitrogen (NO3-N), ammonia nitrogen (NH3-N), total Kjeldahl nitrogen
(TKN), ortho-phosphorus (PO4-P), total phosphorus (TP), chemical oxyge
n demand (COD), and total suspended solids (TSS). Storm flow quality o
f the two main tributaries to Lincoln Lake was monitored from Septembe
r 1991 to April 1994. Significant decreases (from 23 to 75% per year)
in both concentrations and mass transport of NO3-N, NH3-N, TKN, and CO
D occurred concurrently with BMP implementation. The decreases in nitr
ogen and COD concentrations and mass transport are attributed to BMP i
mplementation, and the BMP most responsible for these decreases is mos
t likely nutrient management.