Importance of Position to Biological Processes in

Agenda Introduction and Historical Perspective: Tim Kratz Fish: Tom Hrabik Macroinvertebrates: Amina Pollard Snails: David Lewis Macrophytes: Karen Wilson Discussion welcomed throughout!! Milestones in the Evolution of the Landscape Position Idea 1980: LTER proposal funded – includes multilake study design 1981: First External Advisory Committee Meeting – recommends choosing lakes in same hydrologic flow system 1983: Eilers et al. paper is published – demonstrates importance of hydrologic setting for acid rain analyses. Milestones in the Evolution of the Landscape Position Idea 1986 and 1988: Kenoyer and Krabbenhoft thesis dissertation work – demonstrates hydrogeochemical mechanism for landscape position effects on groundwater and chemistry 1988: Intersite Workshop on Variability in North American Ecosystems – shows linkage between landscape position and lake dynamics Interannual Variability Variability and LandscapePosition (Rank C.V.) 2 3 4 5 6 Landscape Position of Lake Upland Lowland Milestones in the Evolution of the Landscape Position Idea 1990: First Temporal Coherence paper published – shows that biological variables were less coherent than chemical or physical variables Coherence of Biological, Chemical, and Physical Parameters 1.0

0.5

0 Coherence (r) -0.5 Biological Chemical Physical Milestones in the Evolution of the Landscape Position Idea 1990: First Temporal Coherence paper published – shows that biological variables were less coherent than chemical or physical variables 1994: NTL gets “augmentation” award – allows collaboration with ELA, Dorset 1994: NTL receives “international” award – provides funding for cross-site workshop on organization of lake districts Milestones in the Evolution of the Landscape Position Idea 1995: Workshop with ELA and Dorset Scientists – regionwide response to drought project started 1995: Invited presentations at two national meetings – 7 lakes focus at NABS meeting – Northern Highland focus at ESA meeting – becomes clear that more biological data are needed Specific Conductance

200 100 -1 50

uS cm 10 5 -3 -2 -1 0 +1 +2 +3 Lake Order Fish Species Richness

30 20 10 Number 0 -3- 3 -2- 2 -1- 1 00 +11 +22 +33 LakeL a k Ordere O r d e r Milestones in the Evolution of the Landscape Position Idea 1996: Chemical response to drought paper published in L&O February 1997: Cross-site workshop on Ecological Organization of Lake Districts – representatives from 13 regions compare data – idea for special issue of Freshwater Biology conceived – first papers with multiple lake district comparisons are planned Milestones in the Evolution of the Landscape Position Idea 1997: Link between coherence and landscape position established Landscape Position and Coherence are Linked (Baines et al.) ) 2 1.0 0.8 0.6 0.4 0.2 0.0 0.0 0.2 0.4 0.6 0.8 1.0 Calcium Coherence (r Calcium Coherence % Groundwater Milestones in the Evolution of the Landscape Position Idea 1998-99: Cross-site workshop analyses completed Multiple Lake Districts (Soranno et al.)

Wisconsin LTER Adirondacks Saskatchewan 120 35 1800

80 30 1200

40 25 600

Green Lakes, CO Loch Vale, CO Tennessee 24 16 300

18 12 200

Conductivity 12 8 100

Landscape Position Lake Order and Lake...

Status Variability Coherence

Lake Order

Lake Order Lake Order Milestones in the Evolution of the Landscape Position Idea September 1997: Tom Frost leaves for NSF – money becomes available for additional field work 1998: Landscape Position Project Starts Major Issues

Most of focus has been on physical and chemical attributes For biology dispersal is important There is confounding between a lake’s chemistry and its connectivity Area andConnectivity areCorrelated

Total Number of Lakes 20 40 60 80 0 0.25 1.25 2.25 3.25 Log (Lake area + 1) Streams Without Lakes 1.0 0.5 0

Proportion without Streams Design of Landscape Position Project Lake Choice: – high vs low ionic strength (landscape position) – seepage vs drainage (connectivity) – major watersheds (biogeography) – ~16 lakes in 1998; 19 more targeted for 1999. Allows analysis of “conductivity” vs “connectivity” Design of Landscape Position Project Measurements: – water chemistry, algae, macrophytes, , macroinvertebrates, fish, habitat characteristics, structure (isotopes)