TITLE:
The Limnology of a Mississippi River Alluvial Plain Oxbow Lake Following the Application of Conservation Practices
AUTHORS:
Scott Knight, Robert Cullum, Richard Lizotte
KEYWORDS:
Chlorophyll, Nutrients, Non-Point Pollution, Water Quality, Watershed
JOURNAL NAME:
Journal of Water Resource and Protection,
Vol.7 No.9,
July
9,
2015
ABSTRACT: From 1995 and 2011, Beasley Lake watershed near Indianola, MS, was subjected to a variety of conservation measures designed to reduce water velocity, erosion and discharge of sediment laden water. Water quality monitoring during the period indicated a number of long term trends and relationships between the parameters measured. Conservation practices reduced sediments and nutrients during the course of the study that resulted in increased Secchi visibility and chlorophyll a. Annual mean dissolved oxygen decreased slightly over time and was strongly dependent upon temperature, and weakly associated with varying salinity and pH. Total phosphorus, ammonium nitrogen and nitrate nitrogen showed significant downward trends from 1995 through 2011. Chlorophyll a concentration was significantly dependent upon total nitrogen but not phosphate, indicating nitrogen limiting conditions. Watershed based conservation practices significantly changed the long term water quality of Beasley Lake by reducing sediment and nutrients, increasing water clarity and boosting primary production as indicated by chlorophyll a.