P-66
"Influences of Watershed Land Uses On Stream Water Quality in Southeast Arkansas"
S. Shrestha, Y. Chen*, J. Farrelly
Aquaculture /Fisheries Center, University of Arkansas at Pine Bluff,
1200 N. University Drive, Mail slot 4912, Pine Bluff, Arkansas 71601,
Wetland programs (e.g., Wetland Reserve Program and Conservation Reserve Program) have been implemented in Arkansas as conservation approaches to reduce environmental impacts from agricultural activities. Wetlands are generally considered as sinks for pollutants, whereas croplands affect streams by leaching out nutrients. However, there is limited information about effects of these watershed land uses on stream water quality in Arkansas. Replicate streams from both types of land uses (i.e., five in wetlands and four in croplands) were sampled monthly from April to December, 2012. Various water quality parameters, including pH, temperature, turbidity, salinity, conductivity, dissolved oxygen (DO), total alkalinity, total hardness, chloride, total suspended solids (TSS), total ammonia nitrogen (TAN), nitrate, phosphate, total nitrogen (TN), and total phosphorus (TP), were analyzed from these streams. Repeated measures analysis of variance (ANOVA) was used to assess effects of watershed land uses on stream water quality. Significant difference was determined when P< 0.05.
Higher overall mean ± SD of pH (6.87 ± 0.71 and 7.55 ± 1.20 in wetland and cropland streams, respectively), DO (4.14 ± 2.27 and 4.91 ± 1.61 mg/L in wetland and cropland streams, respectively), TSS (36.71 ± 28.25 and 48.43 ± 25.91 mg/L in wetland and cropland streams, respectively), TAN (0.0548 ± 0.022 and 0.3213 ± 0.45 mg/L in wetland and cropland streams, respectively), chloride (44.91 ± 21.0 mg/L and 74.24 ± 40.85 mg/L in wetland and cropland streams, respectively), nitrate (0.751 ± 0.2385 and 1.51 ± 1.74 mg/L in wetland and cropland streams, respectively), total alkalinity (71.35 ± 26.20 mg/L and 105.325 ± 36.43 mg/L in wetland and cropland streams, respectively), and total hardness (89.81 ± 46.99 and 144.325 ± 86.42 mg/L in wetland and cropland streams, respectively) were observed. The current study found that the implemented wetland programs in southeast Arkansas may have improved the water quality in adjacent streams.