Presentation on theme: "Bathymetry and Water Chemistry of the Lucas Pond Mikaela Campbell, Jeff McDonald, Joshua Stedman, & Sierra Grove."— Presentation transcript:
Bathymetry and Water Chemistry of the Lucas Pond Mikaela Campbell, Jeff McDonald, Joshua Stedman, & Sierra Grove
Background Limnological Chemical and Physical Analyses Temperature profile Dissolved oxygen profile Conductivity profile Light irradiance Total phosphorus Chlorophyll a Importance of Chemical and Physical Analyses Ecological and economical reasons Consequences of Poor Management Algal Blooms Fish Kills Economical impacts
Background Continued Bathymetry Is the study and mapping of underwater depths of a body of water Importance of Bathymetry Navigation Possible fish locations Where aquatic vegetation might occur How did we get this data?
Goals Increase Water Quality Create a Sustainable Fishery
Methods Bathymetric Mapping GPS points and depths recorded using Humminbird 365i dual beam transducer unit Mapped collected points using DrDepth software Water Volume and Sediment Deposition Surface area * avg. depth Sediment depth * area Chemical Water Properties Used YSI-55 to develop profiles Used van Dorn sampler to take triplicate samples of Chlorophyll a and total phosphorus at deepest point within the pond
Physical Results Deepest Point was 7.5ft (~2.5m) Average Secci Depth was 1.29m
Physical Results Low Water Volume 9.617e^004 ft 3 Area 2.289e^004 ft 2 Average Depth 4.2ft High Water Volume 1.522e^005 ft 3 Area 3.219e^004 ft 3 Average Depth 4.7ft
Results - Total Phosphorous Total P – ranged from µg/L Greatest at depth of 1m Also the most varied
Results - Chlorophyll-a Ranged form (SE 0.33) at the surface to (SE 1.18) at 2m of depth. Low Readings Makes sense because of the low P levels
Results ● Gathered with a YSI-85 ● Low readings ● Change at 1.5m of depth (µg/L)
Discussion - Total Phosphorus and Chlorophyll-a ❏ Total Phosphorus (mean µg/L) ❏ Low total phosphorus limits the amount of primary production ❏ Chlorophyll-a (mean 14.91) ❏ Primary production low due to phosphorus limiting ❏ Nutrient Supplementation would increase the available total P and increase 1 o production
Discussion - Temperature ❏ Temperature ❏ Isothermic - mean 10.2 o C and 0.27 std dev ❏ In the summer pond may exceed 20 o C and thus would not be suitable for cold water species such as trout
Discussion - Oxygen ❏ Oxygen remains high from surface to 2 m ( mg/L) ❏ 2.5 m drops to 3.5 mg/L creating a habitat that is unsuitable to fish ❏ 0-2 m oxygen levels suitable for fish to occupy ❏ When pond warms, anoxic conditions may exist throughout the pond
Management Plan Artificial habitat - fish attractors, blocks, etc. Aeration - Prevent anoxic conditions Nutrient Supplementation Increase food base Stocking of fishes - Sport and Forage maxresdefault.jpg
Aeration ❏ Improve water quality ❏ Circulate pond and keep nutrients available ❏ Decrease likelihood of winterkill ❏ Increased dissolved oxygen (Willis et al. 2010, Austin et al. 1996)
Fertilization ❏ Inorganic fertilizer of (20% N, 20% P 2 0 5, and 5% K20) ❏ Found to support four to five times more biomass than unfertilized ponds (Willis et. al 2010) and has a direct effect on phytoplankton.
Trophy Bass ❏ Stock fingerling largemouth bass after fertilization (Austin et al. 1996) ❏ After four years reduce densities of cm LMB to allow for rapid growth of remaining fish ❏ Release fish over 38 cm, except for the occasional trophy (Willis et al. 2010). largestfreshwaterfish.com
Forage Fish ❏ Abundant and diverse prey base ❏ Rainbow trout are great option because they will not reproduce in a pond ❏ Alternative angling dnr.maryland.gov
Citations Austin, M., H. Devine, L. Goedde, M. Greenlee, T. Hall, L. Johnson, and P. Moser Ohio pond management handbook: a guide to managing ponds for attracting wildlife. Ohio Department of Natural Resources. Accessed 12/9/13. Burns, N.M., Rockwell, D.C., Bertram, P.E., Dolan, D.M., and Ciborowski, J.J.H Trends in temperature, secchi depth, and dissolved oxygen depletion rates in the central basin of Lake Erie, Journal of Great Lakes Research 31: Wetzel, Robert Limnology. 3rd Edition. Academic Press pp. Wilhelm, F. M Lecture. Fish 415 Limnology. University of Idaho Wilhelm, F. M Laboratory Session. Fish 415 Limnology. University of Idaho Willis, D.W., R.D. Lusk, J.W. Slipke Farm ponds and small impoundments. Pages in W.A. Hubert and M.C. Quist, editors. Inland fisheries management in North America, 3rd Edition. American Fisheries Society, Bethesda, Maryland..