St. Johns River Water Management District...St. Johns River Water Management District Spring Nitrate Trends (SJRWMD, FGS and USGS data) 0 0.5 1 1.5 2 2.5 3 Nitrate-Nitrite as N (NOx-N)

St. Johns River Water Management DistrictSt. Johns River Water Management District

Robert A. Mattson, CEP, CSEEnvironmental Scientist V

Bureau of Water Resources

St. Johns River Water Management District

Long-term Studies of Ecological/Biological Trends in Florida

Spring-Run Streams

• Few– DEP Parks – Monitoring submerged vegetation in

Ichetucknee River; manatee populations in Volusia Blue Spring

– SJRWMD – Silver River Retrospective Study; comparison of Odum work (1950s) with conditions 2004-05. SJRWMD Special Publication SJ2007-SP4

– SJRWMD – Comparison of submerged macrophyte communities in 14 spring-run streams in 2015 with historic studies. SJRWMD Technical Publication SJ2019-2


Spring Flow — Silver Springs

100

200

300

400

500

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700

800

900

1000

1100

1200

1300

1400

1932

1939

1942

1949

1955

1958

1961

1965

1968

1971

1975

1978

1981

1984

1987

1990

1993

2000

2003

2009

2012

2016

Silver River near Ocala Discharge

ft3 /

seco

nd


Spring Nitrate Trends(SJRWMD, FGS and USGS data)

0

0.5

1

1.5

2

2.5

3

Nitr

ate-

Nitr

ite a

s N

(NO

x-N

) m

g/L

Sample Date

Wekiwa Springs Rock Springs Blue Springs Silver Springs Background NOx-N


The IssueChanges in Biological Communities

Weeki Wachee 1951

Weeki Wachee 2006

Source: Fla. State Archives

A. Pinowska, Michigan State Univ.

Silver Springs 1950s Photo by Bruce Mozert

Silver Springs 2010 SJRWMD


Objectives• Exploratory using published work

• Compare data from selected current and historical biological surveys in springs/ spring-run streams

• Evaluate comparability of the data

• What does this tell us (trends)?

• Implications?


Comparison of StudiesFactors considered

• Stations – geographic locations (lat/long), number of stations per spring/stream

• Field collection methods – quadrat size, number of sample replicates per site, collection methodology

• Laboratory methods (if applicable)


Color Key for Bar Charts(Based on best professional judgement)

• Data appear to be comparable with good certainty

• Data moderately to marginally comparable with some uncertainty

• Data not comparable with high degree of uncertainty


Submerged Macrophyte Studies(Published studies)


Odum 1956

Dutoit 1978

Canfield and Hoyer

1988

Duarte and Canfield

1990

PBS&J/UF 2003-04

50 yr 2004

SJRWMD/Amec 2015

Wacissa River XX XX XX

Ichetucknee River XX XX XX XX XX

Manatee Spring XX XX XX

Rainbow River XX XX

Weeki Wachee River XX XX

Silver River XX XX XX XX

Rock Springs Run XX XX

Silver Glen Spring XX XX

Juniper Creek XX XX

Alexander Springs Crk XX XX XX

Wekiva River XX XX XX


Submerged Macrophytes

0

100

200

300

400

500

600

700

Odum 1956 Duarte & Canfield1990

50 yr 2004 SJRWMD/Amec2015

Mea

n St

andi

ng C

rop

(g

dry

wei

ght/m

2 )Silver River (# sites sampled)

(4)

(2)

(?)

(?)



0

5

10

15

20

25

Headspring Rice Marsh Floodplain

SAV

Acre

s

River Reach

Ichetucknee River Mapped SAV Cover

1979 2003

Sources: 1979-Dutoit; 2003-PBS&J/UF



0

500

1000

1500

2000

2500

3000

Dutoit 1978 Duarte &Canfield 1990

PBSJ/UF 2003 PBSJ/UF 2004 SJRWMD/Amec2015

Mea

n St

andi

ng C

rop

(g

dry

wei

ght/

m2 )

Ichetucknee River (# sites sampled)

(2) (2)(3)

(2)

(?)



0

50

100

150

200

250

300

350

400

450

Canfield & Hoyer 1988 Duarte & Canfield 1990 SJRWMD/Amec 2015

Mea

n St

andi

ng C

rop

(g

dry

wei

ght/

m2 )

Wekiva River (# sites sampled)

1985-86

(3)

(2)

(>20)



0

1

2

3

4

5

6

2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019

Mea

n Br

aun-

Blan

quet

Sco

reWekiva Spring Run Submerged Macrophyte Cover

SJRWMD Data - WEKR 05

Vallisneria Najas Hydrilla



0

1

2

3

4

5

2005 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019

Mea

n Br

aun-

Blan

quet

Sco

reMean Vallisneria Cover - Wekiva River nr SR 46 (WEKR 18)

WSI SJRWMD

1

2

1 – Hurricanes Charley, Frances & Jean in 2004; 2 – Hurricane Irma in 2017


Quantitative Algal Studies(Published studies)


Stevenson et al. 2003

GW Labs 2007-09

SJRWMD/Amec 2015

Wakulla River XX XX

Wacissa River XX XX

Ichetucknee River XX XX

Manatee Spring XX XX

Rainbow River XX XX

Weeki Wachee River XX XX

Silver River XX XX

Rock Springs Run XX XX

Silver Glen Spring XX XX XX

Juniper Creek XX XX XX

Volusia Blue Spring XX XX

Alexander Springs Creek XX XX XX

Wekiva River XX XX XX


0

5

10

15

20

25

Spring2003

Fall2003

Feb2007

Jun2007

Sep2007

Dec2007

Mar2008

Jul2008

Sep2008

Dec2008

Apr2009

Spring2015

Fall2015

Mea

n As

h-Fr

ee D

ry W

eigh

t (g

/m2 )

Alexander Spring Epiphyte Biomass(headspring reach sampled)

Epiphytic Algae

Stevenson GreenWater Labs SJRWMD/Amec


Epiphytic Algae

Stevenson GreenWater Labs

0

20

40

60

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120

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200

Spring2003

Fall2003

Feb2007

Jun2007

Sep2007

Dec2007

Mar2008

Jul2008

Sep2008

Dec2008

Apr2009

Spring2015

Fall2015

Mea

n Ch

loro

phyl

l a

(mg/

m2 )

Alexander Spring Epiphyte Biomass(headspring reach sampled)

SJRWMD/Amec

NOTE: the “50-yr” study in Silver Springs also saw high epiphyte variability


Epiphytic Algae

Stevenson GreenWater Labs

0

20

40

60

80

100

120

Spring 2003 Fall 2003 Jul 2008 Oct 2008 Jan 2009 May 2009 Spring 2015 Fall 2015

Mea

n Ch

loro

phyl

l a (

mg/

m2 )

Sample Date/Season

Wekiwa Spring Run Epiphyte Biomass

SJRWMD/Amec

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5

10

15

20

25

30

Spring 2003 Fall 2003 Jul 2008 Oct 2008 Jan 2009 May 2009 Spring 2015 Fall 2015

Mea

n As

h-Fr

ee D

ry W

eigh

t (g

/m2 )

Wekiwa Spring Run Epiphyte Biomass


Epiphytic Algae

050

100150200250300350400450

Odum 1956 50-yr 2004 SJRWMD/Amec 2015

Mea

n Dr

y W

eigh

t (g

/m2 )

Upper Silver River (1200 m) Epiphytes

050

100150200250300350400450

Odum 1956 50-yr 2004 SJRWMD/Amec 2015

Mea

n Dr

y W

eigh

t (g

/m2 )

Upper Silver River (1200 m) Epiphytes

Epiphyte DW on blades x 24.3 m2 of

blade surface area per m2

of bottom


Macroalgae

0

100

200

300

400

500

600

700

800

900

Spring 2003 Fall 2003 Spring 2015 Fall 2015

Mea

n As

h-Fr

ee D

ry W

eigh

t (g

/m2 )

Volusia Blue Spring Macroalgae Biomass

Stevenson(multiple stations)

SJRWMD/Amec(1 transect)


Macroalgae

Stevenson(multiple stations)

SJRWMD/Amec(1 transect)

0

1,000

2,000

3,000

4,000

5,000

Spring 2003 Fall 2003 Spring 2015 Fall 2015

Mea

n Ch

loro

phyl

l a

(mg/

m2 )

Alexander Spring Macroalage Biomass


All Algae(Epiphytes and macroalgae)

0

1

2

3

4

5

6

2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019

Mea

n Br

aun-

Blan

quet

Sco

re

Alexander Spring Mean Algal Cover (all algae)SJRWMD Data - ALXC 05


Fish Community

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100

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600

Odum 1950s Knight 1970s 50 Yr 2004 WSI 2009

kg/h

ecta

re

Silver Springs - Total Fish BiomassUpper 1200 m


Silver Springs Fish Community

1

10

100

1000

Odum 1950s Knight 1970s 50-Yr Retro

Biom

ass (

kg/h

a)

Mullet Catfish Centrarchidae Gizzard shad Other


Silver Springs Fish Community

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10

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40

50

60

Odum 1950s Knight 1970s 50 Yr 2004 WSI 2009

kg/h

ecta

re

Sunfish Biomass - Silver SpringsUpper 1200 m


Fish Community

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10

20

30

40

50

60

2001 2002 2003 2007-08 2014-15

Dens

ity (f

ish

m-2

mea

n +

SD)

Stetson – Blue Spring Fish Abundance


Benthic Macroinvertebrates

0

10

20

30

40

50

60

Station 1 Station 2

Taxa

Ric

hnes

s (T

otal

# S

peci

es)

Weeki Wachee River Benthic Invertebrates

Sloan 1953-54 SJRWMD/Amec 2015

Collection methods different; stations not in exact same location


Benthic Macroinvertebrates

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2

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6

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18

Oct-07 Feb-08 Jun-08 Nov-08 Sep-14 Nov-14 Mar-15 May-15 Aug-15

Tota

l # T

axa

Sample Date

Volusia Blue Spring Total Snail Taxa RichnessUpper Reach Middle Reach Lower Reach

FDEP SJRWMD/Stetson


Florida Manatee

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100

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600

700

1975 1980 1985 1990 1995 2000 2005 2010 2015 2020

# M

anat

ees

Year

Manatee Population in Blue Spring 1978-2018

Total Max. Daily

Data: Fla. Park Service and Save the Manatee Club


Common Findings• No understanding of long-term biological trends

in spring-run streams.

• Submerged macrophyte abundance (as g DW/m2); mixed trends. Are there less macrophytes in springs? For some, “Yes”, others, “No”.

• High variability in epiphytic algal abundance; mixed trends across systems. Is there more algae in springs? Can’t really say from the data; one result suggests “Yes”.



Common Findings• Fish abundance highly variable; some changes

in community composition. Are there more or less fish in Florida spring-run streams? Hard to say from the data, so “Inconclusive”. Have fish communities changed? Tentatively, “Yes”.

• Benthic macroinvertebrates; very little historic data. Have benthic communities in springs changed? “Inconclusive”.



Common Findings• Manatee abundance at Blue Spring during

winter season well-tracked; good understanding of long-term trends. Are manatee populations doing well? In northeast Florida, “Yes”.

• Biological monitoring data are important to better understand what’s happening in springs; people see the biology.



Biological Studies in Florida Spring-Run Streams Current

• Various investigators 1999-current – turtle surveys (Wekiva R., V. Blue Spring, G. Blue Spring/Santa Fe R.)

• Work and Gibbs (Stetson) 2001-current – fish population surveys in Volusia Blue Spring

• DEP Parks 1989-current – vegetation monitoring in Ichetucknee River; 1978-current – manatee monitoring in Volusia Blue Spring

• SJRWMD 2007-current – SAV (macrophytes and algae) surveys in SJR spring-run streams

• Florida Springs Institute 2011-current – ecological monitoring in priority spring-run streams


Conclusions

• It’s the Biology, stx#&d !

• Need biological monitoring to support hydrologic and water quality data

• Need to agree on standard methodologies so we can compare data among springs and over time

• What do you want to know? This drives what data you collect (Mapping? Field sampling?)


www.sjrwmd.com/springsThank you

[email protected]

Documents

St. Johns River Water Management District...St. Johns River Water Management District Spring Nitrate Trends (SJRWMD, FGS and USGS data) 0 0.5 1 1.5 2 2.5 3 Nitrate-Nitrite as N (NOx-N)