Methods

Sites are designated according to the NTL numbering scheme established for the shoreline of the south basin of Trout Lake and its islands. The four sites (Trout-07, 46.01809769, -89.65571661; Trout-31, 46.0430698, -89.67157974; Trout-50, 46.01729465, -89.69461296; Trout-56, 46.01921135, -89.6813004) used by the macrophyte component are also used in the NTL fish and crayfish sampling. The site descriptions specify a transect line along which presence or absence data is recorded for all macrophyte species. A 0.25 M2 ring placed at 1 meter intervals (except site 7 - 0.5 to 1 M depth where the ring is placed at 2 meter intervals) along the transect designates the sampling quadrat. Using SCUBA, species data are recorded along with the total number of quadrats encountered between the following depth intervals: 0.5-1 M, 1-2 M, 2-3 M and 3-5 M. These depth intervals have been permanently established with markers consisting of a commercial Earth Anchor set in the lake bottom with 2 floats secured to it near the bottom. Large boat bumpers are used on the anchors at 3 and 5 meters. Between 28 and 52 quadrats are examined within each depth interval at each site.
Pre-1987 Data. In 1987, permanent line transects were established at each of the sites. Biomass samples and line transects observed before 1987 were set by more general descriptions at the site and were not identical year to year.

Methods

Sites are designated according to the NTL numbering scheme established for the shoreline of the south basin of Trout Lake and its islands. The four sites (Trout-07, 46.01809769, -89.65571661; Trout-31, 46.0430698, -89.67157974; Trout-50, 46.01729465, -89.69461296; Trout-56, 46.01921135, -89.6813004) used by the macrophyte component are also used in the NTL fish and crayfish sampling. The site descriptions specify a transect line along which presence or absence data is recorded for all macrophyte species. A 0.25 M2 ring placed at 1 meter intervals (except site 7 - 0.5 to 1 M depth where the ring is placed at 2 meter intervals) along the transect designates the sampling quadrat. Using SCUBA, species data are recorded along with the total number of quadrats encountered between the following depth intervals: 0.5-1 M, 1-2 M, 2-3 M and 3-5 M. These depth intervals have been permanently established with markers consisting of a commercial Earth Anchor set in the lake bottom with 2 floats secured to it near the bottom. Large boat bumpers are used on the anchors at 3 and 5 meters. Between 28 and 52 quadrats are examined within each depth interval at each site.
Pre-1987 Data. In 1987, permanent line transects were established at each of the sites. Biomass samples and line transects observed before 1987 were set by more general descriptions at the site and were not identical year to year.

Methods

Sites are designated according to the NTL numbering scheme established for the shoreline of the south basin of Trout Lake and its islands. The four sites (Trout-07, 46.01809769, -89.65571661; Trout-31, 46.0430698, -89.67157974; Trout-50, 46.01729465, -89.69461296; Trout-56, 46.01921135, -89.6813004) used by the macrophyte component are also used in the NTL fish and crayfish sampling. The site descriptions specify a transect line along which presence or absence data is recorded for all macrophyte species. A 0.25 M2 ring placed at 1 meter intervals (except site 7 - 0.5 to 1 M depth where the ring is placed at 2 meter intervals) along the transect designates the sampling quadrat. Using SCUBA, species data are recorded along with the total number of quadrats encountered between the following depth intervals: 0.5-1 M, 1-2 M, 2-3 M and 3-5 M. These depth intervals have been permanently established with markers consisting of a commercial Earth Anchor set in the lake bottom with 2 floats secured to it near the bottom. Large boat bumpers are used on the anchors at 3 and 5 meters. Between 28 and 52 quadrats are examined within each depth interval at each site.
Pre-1987 Data. In 1987, permanent line transects were established at each of the sites. Biomass samples and line transects observed before 1987 were set by more general descriptions at the site and were not identical year to year.

Methods

Sites are designated according to the NTL numbering scheme established for the shoreline of the south basin of Trout Lake and its islands. The four sites (Trout-07, 46.01809769, -89.65571661; Trout-31, 46.0430698, -89.67157974; Trout-50, 46.01729465, -89.69461296; Trout-56, 46.01921135, -89.6813004) used by the macrophyte component are also used in the NTL fish and crayfish sampling. Five replicate quadrats (0.25 M2) are harvested for all above ground biomass at each site at each of three nominal depths: 1.5 M, 2.5 M and 4 M. Samples are removed along a line parallel to shore - located midway between sites for cover estimates. Four sites with 3 depths and 5 replicates yields 60 samples. In the lab, samples are separated by species and are dried and weighed. From 1989 to 2008 plants were placed in labeled paper bags oven dried, and weights recorded. Biomass weights were determined by weighing dried plants in paper bags and using an average tare for the bags. Consequently, values in the data base can be negative and should be considered as present in very small amounts.
Pre-1987 Data. In 1987, permanent line transects were established at each of the sites. Biomass samples and line transects observed before 1987 were set by more general descriptions at the site and were not identical year to year.

Methods

Aquatic macrophytes are sampled from a boat at stations located at depths from 1 to 4 meters at 0.5-m intervals along transects perpendicular to the lake shoreline of the four primary study lakes in the Madison area (Lakes Mendota, Monona, and Wingra, and Fish Lake) from June to August. A weighted, double-headed garden rake is cast off the front left, front right, rear left, and rear right of the boat and then dragged approximately 2 meters across the bottom by means of an attached line. The total plant mass and the total filamentous algae mass in each tow is measured. To the maximum extent possible, water is squeezed from the plants to minimize the amount of water present in the final weight. Weights are recorded in the boat using field scales. Weights from the 4 rake casts at each station can be averaged to compute overall average weights for plant mass and for filamentous algae mass at the station.
Detailed Macrophyte Sampling description.
Using the site book and the depth measuring pole, move to the 1 meter depth mark and throw both anchors. From the Macrophyte Depth Table, find the distance to throw out the rake and the meter mark that the line should be drawn to. The table is calculated to determine the starting and ending meter marks to draw in the line to allow the rake to drag 2 meters on the lake bottom. Pull the rake quickly out of the water. If a significant amount of dirt has been brought up with the plants (i.e. the weight of the dirt will add significantly to the total weight), wash the plants. Depending on the volume of the plants, wash them either by keeping them in your hands and dunking them in the lake or by putting them in a bucket with drain holes. Separate the filamentous algae from the rest of the plant material. Squeeze out as much water as possible (it may be necessary to divide up the plant material into portions to effectively squeeze out the water). Weigh the plant material (minus the filamentous algae) and record the total weight. Weigh the filamentous algae and record the weight. Repeat the above steps until 4 rake tosses have been thrown. Move to the next half-meter depth. Macrophytes are collected at each half-meter water depth from 1 meter to 4 meters.

Methods

Aquatic macrophytes are sampled from a boat at stations located at depths from 1 to 4 meters at 0.5-m intervals along transects perpendicular to the lake shoreline of the four primary study lakes in the Madison area (Lakes Mendota, Monona, and Wingra, and Fish Lake) from June to August. A weighted, double-headed garden rake is cast off the front left, front right, rear left, and rear right of the boat and then dragged approximately 2 meters across the bottom by means of an attached line. For each rake cast, filamentous algae and any aquatic macrophyte species present are assigned a density rating from 0-5 based on the extent of coverage of the upper rake head. Determination of extent of coverage involves judgment of the surveyor as to the number of rake teeth and area of teeth covered by each species. It is necessary to separate plants to assess individual species coverage. Ratings from the 4 rake casts at each station can be averaged to compute an overall density rating for each species found at the station.
Detailed Macrophyte Sampling description.
Using the site book and the depth measuring pole, move to the 1 meter depth mark and throw both anchors. From the Macrophyte Depth Table, find the distance to throw out the rake and the meter mark that the line should be drawn to. The table is calculated to determine the starting and ending meter marks to draw in the line to allow the rake to drag 2 meters on the lake bottom. Pull the rake quickly out of the water. Before removing the plant material from the rake, drape the long strands over the rake and gently push the plant material down on the rake. Assign a rake rating (from 1 to 5) depending on how much the plant material covers the rake prongs. The rake prongs are painted in 20 percent increments. If the plant material only covers the lowest 20 percent of the rake prongs, assign the rake rating a 1. If the plant material covers between 20 percent and 40 percent of the rake prongs, the rake rating is a 2, and so on. If a significant amount of dirt has been brought up with the plants (i.e. the weight of the dirt will add significantly to the total weight), wash the plants. Separate the filamentous algae from the rest of the plant material. Separate and identify the individual plant species, throwing out any dead plant material. Give the filamentous algae and each plant species a rake rating (note that it is often necessary to visualize how much space each species would take up on the rake prongs rather than actually placing each species onto the rake). If a plant species can not be identified, take a sample back to the lab by putting it in a ziplock bag with a small amount of water and temporarily storing it in a cooler. Repeat the above steps until 4 rake tosses have been thrown. Normally 2 rake tosses are thrown out each side of the boat to an area where the water depth is known to be at the desired depth. Move to the next half-meter depth. Macrophytes are collected at each half-meter water depth from 1 meter to 4 meters.

Methods

Sites are designated according to the NTL numbering scheme established for the shoreline of the south basin of Trout Lake and its islands. The four sites (Trout-07, 46.01809769, -89.65571661; Trout-31, 46.0430698, -89.67157974; Trout-50, 46.01729465, -89.69461296; Trout-56, 46.01921135, -89.6813004) used by the macrophyte component are also used in the NTL fish and crayfish sampling. Five replicate quadrats (0.25 M2) are harvested for all above ground biomass at each site at each of three nominal depths: 1.5 M, 2.5 M and 4 M. Samples are removed along a line parallel to shore - located midway between sites for cover estimates. Four sites with 3 depths and 5 replicates yields 60 samples. In the lab, samples are separated by species and are dried and weighed. From 1989 to 2008 plants were placed in labeled paper bags oven dried, and weights recorded. Biomass weights were determined by weighing dried plants in paper bags and using an average tare for the bags. Consequently, values in the data base can be negative and should be considered as present in very small amounts.
Pre-1987 Data. In 1987, permanent line transects were established at each of the sites. Biomass samples and line transects observed before 1987 were set by more general descriptions at the site and were not identical year to year.

Methods

Details of field collections can be found in Wilson, K.A. 2002. Impacts of the invasive rusty crayfish (Orconectes rusticus) in northern Wisconsin lakes. Ph.D. Dissertation. University of Wisconsin, Madison.

Methods

14C-PRIMARY PRODUCTIVITYEQUIPMENT:Field:PPR float with line and clips for hanging bottles at selected depthsPPR field boxes containing:18, 60 mL reagent bottles wor glass stoppers, plus extra bottles and tops.2, 100-1000 microL automatic pipettor and several tipslab gloves and plastic apronplastic bag for used gloves and pipette tipsextra clips for hanging bottleswater pumpLab:6-tower vacuum filter apparatus4.7 cm Whatman GForF filtersScintillation vials with labeled caps (label includes lake, day, "D" or "L" for darkor light bottle, and depth, respectively. (e.g.: "L145 L1"; "W224 D6")REAGENTS:10 microCi 14C-bicarbonate (2 microCi mL-1)Dichlorophenol-dimethyl urea (DCMU) saturated solution0.1 N HCLScintillation fluor (Biosafe)PROCEDURE:(Observe safe radioisotope handling techniques at all times during this analysis!)A. In lab (morning, before going to the field)1. Transfer 14C from ampule to labeled scintillation vial with a disposablepipettor (under the fume hood). Put scintillation vial in the field box.2. Replenish supply of lab gloves, pipette tips, and DCMU in the field box.3. Remember to include the PPR float and the field boxes (check contentswith list) in the items loaded into the field vehicle(s).106B. In field1. Rinse and fill 3, 60 mL BOD bottles with water from each depth,corresponding to 100, 50, 25, 10, 5 and 1percent of surface irradiance. Avoidgetting air bubbles in bottles. TRY TO KEEP BOTTLES IN THE DARKAS MUCH AS POSSIBLE.2. Pipette 250 microL of water from each bottle (using the "14C pipettor").3. Pipette an additional 500 microL of water from the 6 dark bottles using the"DCMU pipettor" (the dark bottles are used as a t = 0 control).4. Using the "DCMU pipettor," add 500 microL DCMU to the dark bottles tokill the phytoplankton. (always done before 14C addition.) It isimportant not to contaminate "light" bottles with DCMU! Darkbottles are labeled, and are used only as dark bottles.5. Using the "14C pipettor," Pipette 250 microL of 14C into each of the 18 bottles,starting with the dark bottles to ensure there is enough isotope forcontrols.Summary of subtractions and additions:light bottles dark bottlesremove 250 microL 750 microL (250 plus 500)add DCMU - 500 microLadd 14C 250 microL 250 microL6. Replace stoppers and invert bottles 2 or 3 times to mix. Ensure thatstoppers are well-seated, so they don t come out. It often helps to twist thestopper as you push it into the bottle.7. Suspend bottles at appropriate depths for incubation. Record incubationstart time.8. AFTER 6 HRS: Remove bottles from water and place in carrying caseuntil ready to filter (filtering should be done promptly after removal ofbottles from water). Record incubation finish time. (Incubations usuallygo from ~9:30am-3:30pm)C. In lab (afternoon)1. Have readya. Flask used only for collecting 14C waste107b. Filter towers equipped with 4.7 cm GForF filters. Separate towersshould be used for light and dark (DCMU) bottles.c. Scintillation vials, with caps labeled for all samples.d. A full squirt bottle of 0.1 N HCl and a full squirt bottle of Milli-QTURN OFF THE LIGHTS - THE REST OF THE PROCEDURE SHOULD BEDONE IN DIM LIGHT!2. Prepare 3 totals:a. Add 10 mL scintillation solution (Biosafe) and 100 microL 1 N NaOHto 6 vials (label on cap should include lake, day, "TOT" ,anddepth id).b. Remove 250 microL from one of the light bottles from each depth andadd it to the proper vial. These vials are for calculating the totalamount of 14C added to the bottles.c. Tightly cap the total vials and put aside for later analysis with thescintillation counter3. Samples (process samples in the designated 14C fume hood):a. Empty the entire BOD bottle into the appropriate "light" or "dark"filter tower. Record volume if entire bottle is not filtered.b. Once the sample has filtered completely, rinse the bottle with asquirt of 0.1 N HCl, and filter this rinse. Then rinse the bottlewith water and filter this rinse. Rinse tower with 0.1N HCl, andthen finally with Milli-Q.c. Remove filter by folding it in quarters and place it at the bottom ofthe appropriate scintillation vial. Filter should be compact enoughin the bottom of the vial to be completely covered by thescintillation fluor (which fills half of the vial).d. Dry at 60-70degreeC for 24 hours.e. After drying filters, add 10 mL liquid scintillation solution to vialsand count in scintillation counter (see Scintillation CountingProcedure).D. Clean up:1081. When all samples have been filtered, squirt some acid down the last towerin the line to rinse. When the acid has been pumped out of the line, ventthe tower to expel all liquid. Lift towers to drain completely.2. Rinse BOD bottles and caps three times with hot tap water.3. Radioactive waste goes into a carboy marked and reserved for radioactivewaste. timestimesNOTEtimestimes The total radioactivity in each carboy must beknown; Record the date when 14C is initially put in the carboy and the datewhen the final amount of 14C is put in the carboy.4. Empty the remaining amount of 14C from the scintillation vial taken intothe field into the radioactive waste carboy. Discard the vial in the dryradioactive waste bag.5. Record the amount of radioactivity used in the isotope log book.CALCULATIONS:Use the SYSTAT command file CALCPPR.CMD to calculate primaryproductivity according to the following equation:mg Ctimesm-3timesh-1 =(CPMs - CPMb) times (VincorVfil) times (A) times (1.05)(DPMt) times (Eff) times (T)where:CPMs = counts per minute for sampleCPMb = counts per minute for DCMU controlVine = volume (mL) incubatedVeil = volume (mL) filteredA = total C in sample (in mg Corm3), calculated from sample alkalinity1.05 = isotope discrimination factorDPMt = disintegrations per minute of total amount of 14C added to each bottleEff = efficiency of scintillation fluor calculated from internalstandards for each sampleT = length of incubation (h)2. Use the method in Appendix III, along with measurements of solar radiationtimes andlight extinction from the weekly light profiles, to calculate daily production of thephotic zone and the mixed layer (see Carpenter et al., 1986).times see Pyranograph Method109REFERENCES:Carpenter, S.R., M.M Elser and J.J. Elser. 1986. Chlorophyll production, degradation,and sedimentation: Implications for paleolimnology. Limnol. Oceanogr. 31:112-124.Strickland, J.D.H., and T.R. Parsons. 1968. A practical handbook of seawater analysis.Bull. Fish. Res. Board Can. 167:267-279.Legendre, L., S. Demers, C.M. Yentsch, and C.S. Yentsch. 1983. The 14C method:Patterns of dark CO2 fixation and DCMU correction to replace the dark bottle.Limnol. Oceanogr. 28: 996-1003.

Methods

Macrophyte surveys were conducted on Sparkling Lake, Vilas County, Wisconsin in mid-July of the years 2001 to 2009. Eight sites were chosen that corresponded to trap survey sites for rusty crayfish and represented the range of macrophyte communities in the lake. These sites corresponded to trap survey sites 1, 4, 10, 16, 20, 23, 27, and 35. At each site, we swam a transect perpendicular to shore from 0 to 4 m depths. A tape measure extended from shore to the 4 m depth contour, and buoys were placed at the 1, 2, 3, and 4 m depth contours. We visually estimated the percent cover of each macrophyte species within a 0.24 meter squared quadrat. Quadrats were placed along each transect at 1 m intervals. Thus, we used fewer quadrats on transects with a steeper slope. At site 23, we only found a macrophyte on one event: Vallisneria sp. in 2004.Transect: corresponds to trap survey site number.Quadrat: occur at 1 m intervals starting from shore (0) and going until you reach the 4 m depth contour (highest number).Substrate: substrate within the quadrat categorized as muck, sand, gravel, cobble, logs, leaves, or any combination of these.Abundance: percent cover of each species within the quadrat determined by visual estimation. The percent covers of all species within a quadrat do NOT necessarily add to 100.Depth Interval: depth interval that each quadrat was in. Quadrats between 0 and 1 m deep are in depth interval 1, those between 1 and 2 m deep are in depth interval 2, etc.