1

Water Quality of Potholes in Agricultural Landscapes of East-Brandenburg

(Germany)

Centre for Agricultural Landscape and Land Use Research (ZALF)

Thomas Kalettka1 & Catrin Rudat2

1 ZALF, Institute for Hydrology, tkalettka@zalf.de2 Umweltplan Stralsund Gmbh, cr@umweltplan.de

2

3

0

200

400

600

800

1000

1200

1400

1600

1800M

rz 9

5

Apr

95

Mai

95

Jun

95

Jul 9

5

Aug

95

Sep

95

Okt

95

Nov

95

Dez

95

Jan

96

Feb

96

Mrz

96

Apr

96

Mai

96

Jun

96

Jul 9

6

Aug

96

Sep

96

Okt

96

Nov

96

Dez

96

Jan

97

Feb

97

Ele

ctri

c co

nd

uct

ivit

y [µ

S/c

m]

B_BAP E_20 E_19 E_6 L_17f B_205

Dynamics of water quality parameters of potholes

- Electric conductivity -

Electrolyte poor potholes: B_BAP, E_20, E_19

Electrolyte rich potholes: E_6, B_205, L_17f

4

very softly 0-4°dHsoftly: 4-8°dHmoderate hard: 8-12°dHfairly hard: 12-18°dHhard: 18-30°dHvery hard: >30°dH

Water quality parametersof potholes

- Electrolyte pollution -

y = 0,0257x + 0,7571R2 = 0,7423

0

10

20

30

40

50

60

0 500 1000 1500 2000

Electric Conductivity (uS/cm)

To

tal w

ater

har

dn

ess

(°d

H)

0

5

10

15

20

25

30

35

40

verysoftly

softly moderatehard

fairly hard hard very hard

Sh

are

[%

]

total hardness carbonate hardness

5

dominating hydrophytes: L. min. = Lemna minor; C. sub. = Ceratophyllum submersum

0 182,5 365 547,5 730 912,5 1095 1277,5 1460 1642,5

Day (zero=1.1.1994)

0

0,5

1

1,5

2

2,5

3NH4, SRP, O2 [mg/l]

0

100

200

300

400

500

600Chl a [µg/l]

NH4-N SRP Chl a O2 x 0,1 ice

60 % L.min.

20 % L. min.80 % C. sub.

30 % L.min. 60 %C.sub.

70 % C. sub.

dry

Dynamics of water quality parameters of potholes

- bioproduction and matter dynamics -

Polytrophic

pothole

B-BFA

1993-1998

Characteristics of potholes eutrophication :- summer period: dense hydrophyte stands with reduced species number- winter period: maximum of algae- cyclic reduced oxygen: internal matter loading from the sediment

6

Correlation between phytoplancton and macrophytes

B-S

PF

B-2

07c

B-2

03

B-I

I /8

L -20

L -19

L -18

b

L -18

L -13

B-2

05

B-B

Fa

B-K

LAP

F

BA

PF

0

20

40

60

80

100

120

Ch

loro

ph

y ll A

[µ g

/l ]

MV March-Nov. MV June-Sept.

Macrophytes

dominant

Macrophytes not

dominant

7

Analysis of bioavailability of phosphorus from sediments

Extraction-solution

Extraction time [h] / temp. [°C]

Bindung forms of P

NH4Cl (1 M) 0,5 / 20-25 SRP / NRP Gelöste, unmittelbar verfügbare Phosphate

= im Interstitialwasser und labil an Oberflächen gebunden

BD (0,11 M) 0,5 / 40 SRP

NRP

Reduktant lösliche anorg. Phosphate = an Fe- und Mn-Hydroxide adsorptiv gebunden: Fe(OH)3, FeOOH, MnOOH

An Fe- und Mn-Hydroxide gebundener org. P

NaOH (1 M) 16 / 20-25 SRP

NRP

Baselösliche Phosphate = an Metalloxide von Fe und Al gebunden und gegen OH- austauschbar (Fe2O3, Al2O3)

P in Mikrorganismen, Detritus und Huminstoffen

HCl (0,5 M) 16 / 20-25 SRP

NRP

Säurelösliche Phosphate = Ca- u. Mg-P, Apatit-P

Säurelabiler org. P, hydrolysierter org. P

Residual-P TP Schwer abbaubare bzw. nicht verfügbare Phosphate

= Refraktärer überwiegend org. P

SRP = Soluble Reactive P NRP = Not Reactive P (NRP= TP-SRP) TP = Total P

bioavailability a) direct available P SRP of the NH4Cl-extract

of P b) reductive available P SRP of the BD-extract

c) total available P sum SRP of the extracts

d) not available P residual-P

8

10

9

11

3

8

67

1

2 45

0

1

2

3

4

5

6

7

8

9

10

0 0,5 1 1,5 2 2,5

BD-SRP (mg/gTM)

BD

-Fe

(mg

/g T

M)

1: B-BAP; 2: B-II/8; 3: B-KP;

4: E-19; 5: L-18b; 6: E-6;

7:E.20; 8: L-18; 9: B-BFA;

10: B-207c; 11: B-203

Internal eutrophication by release of phosphorus from sediments

increasing of redox sensitive potential for P-release

Redox soluble Fe(III) bound phosphorus in the sediment

Classification of the eutrophication potential of aquatic pothole sediments

Matter loding disposition BD-SRP (upper 1 cm) [mg/g DM]

Redox sensitive eutrophication potential

high to very high (4-6) > 1.0 very high

moderate (2-4) 0.2-1.0 moderate to high

low (0-2) 0.1-0.2 low

very low (<0) 0-0.1 very low

9

Variables Factor 1 Factor 2

Electric Conductivity 0,95 0,09

SO4 0,87 -0,27

Cl 0,89 0.19

Ca 0,98 -0,01

Mg 0,96 0,01

Total water hardness 0,97 0,05

pH 0,08 0,82

O2 0,15 0,91

TP 0,14 -0,64

Explained Varianz(Own value)

5,36 2,00

Share of total varianz %

60 22

Extraction: Mean components; factor rotation: varimax; Results: Factor loadings of variablesmarked loadings 0,65

(Gruppe 3)

(Gruppe 4)

(Gruppe 1)

(Gruppe 2)

Komponente 2

Komponente 1

-1.5 +1.5

-1.0

+1.5

Cl

Mg

GH.

LFCa

SO4

pHO2

TP

E-32

L-19

L-21 a

L-16

B-207d

E-6

B-II.4

B-II.10

L-18

L-21b

E-50a

B-BFB

B-KP

E-24

E-19

E-12

E-25 L-18b

B-206

B-BAP

L-17c

E-9a

B-BFA

B-SPAL-7

E-3

B-203

E-60

B-207c

L-13

E-31

B-153

L-20

L-17f

E-5

B-300a

Hydrochemical main parameters of potholes in agricultural landscapesHigh, significant correlation (p < 0,05) at 9 from 16 Parameters

PCA-Ordination plot of extracted variables in correlation to 39 potholes

Group 1: P-rich Mineral-poorGroup 2: P-poor Mineral-poorGroup 3: P-rich Mineral-richGroup 4: P-poor Mineral-rich

10

05

1015

2025

3035

4045

50

Lietzen Eggersdorf Müncheberg

Sh

are

(%)

2,5-2,9 3,0-3,4 3,5-3,9 4,0-4,5

Wasser quality (trophic level) of potholes in agricultural landscapes

(modified method by Klapper 1992)

Lietzen (n=15), Eggersdorf (n=15), Müncheberg incl. Eggersdorf (n=59)

(2,5-2,9 = eutroph; 3,0-3,4 = high eutroph; 3,5-3,9 = polytroph; 4,0-4,4 = high polytroph)

low trophic level within arable land = low matter loading disposition      big potholes with wide buffer strips (high buffer capacity)      small potholes within small slightly rolling catchment (low soil erosion)      lacking of input from drainages      soil ramparts at the upper shore (high buffer capacity)

11

Correlation between trophic level and matter loading dispositionof potholes

n = 29; r = 0,79; significant p < 0,001

Assessment of matter loding disposition (MLD) by score system:

MLD = Total (matter loading factors) – Total (buffer capacity of pothole)

Sum of points Sum of points

catchment area (1-5)

catchment relief (1-5)

input by drainage (1-3)

input by water erosion (1-4)

buffer strip width (1-5)

shore width (1-5)

soil ramparts at shore top (1-5)

pothole area (1-5)

n = 29

y = 0,09x + 3,34

R2 = 0,63

2,5

3,0

3,5

4,0

4,5

-6 -4 -2 0 2 4 6 8

Matter loading disposition

Tro

ph

ic l

ev

el

(wa

ter)

12

Trophic level

Parameters oligo-trophic

meso-trophic

weak eutrophic

high eutrophic

weak polytr.

high polytr.

hyper-trophic

1,0-1,4 1,5-2,5 2,5-2,9 3,0-3,4 3,5-3,9 4,0-4,4 4,5-5,0

Nutrients

Spring, MV 3-4, after melting of ice cover [mg/l]

a) SRP

b) TP

c) anorganic N (if TN/TP < 7)

</= 0,005

</= 0,015

</= 0,3

</= 0,015

</= 0,045

</= 0,5

</= 0,2

</= 0,3

</= 1,0

</= 1,2

</= 1,5

</= 1,5

> 1,2

> 1,5

> 1,5

Summer, MW 6-9 [mg/l]

a) SRP

b) TP

c) anorganic N (if TN/TP < 7)

</= 0,002

</= 0,015

</= 0,01

</= 0,005

</= 0,04

</= 0,03

</= 0,1

</= 0,3

</= 0,1

</= 0,5

</= 0,5

</= 0,5

> 0,5

> 0,5

> 0,5

Bioproduction

Chl. A, MV 3-11, after melting of ice cover [mg/l]

Only if macrophytes not dominant 1* </= 3 </= 10 </= 40 </= 60 > 60

Macrophytes/filamentous green algae 2*

Visible depth, MV 3-11 [m]

After melting of ice cover, use only if water level is deep enough for whole year

- >/= 4 >/= 1,5 >/= 1,0 >/= 0,5 >/= 0,2 < 0,2

Water quality classification of potholes (modified after Klapper 1992)

1* - Sum coverage of macrophytes + filamentous green algae </= 50 %

2* - Coverage % of whole surface water area with litoral charakter (maximum of vegetation period), Trophic level indication by species combinations, use only if sum of coverage of macrophytes/filamentous green algae >/= 25 %

13

Species name Trophic level

N* NO3 NH4 P I°

Floating covers / pleustophytes

Lemna gibba 3-4 8 rich rich rich

Lemna minor 2,5-3-4 6 5,0

Spirodela polyrhiza (2)-3 6 rich 5,0

Wolffia arrhiza 3 6

Suspendes mats / pleustophytes

Lemna trisulca (2)-3-(4) 5 moderate

Ceratophyllum submersum (2)-3, 4 7

Ceratophyllum demersum (2)-3, 4 8 rich rich

Fadengrünalgen 3-4

Riccia fluitans 2-2,9 poor moderate

Utricularia vulgaris 2-3 4 poor-moderate

Rooted floating leaf lawn / rhizophytes

Nuphar lutea 2-3-4 6

Potamogeton natans 1-3 5 2,5

Ranunculus aquatilis 3 6

Polygonum amphibium 2-3-4 4 not rich

Rooted submersed plants /rhizophytes

Potamogeton crispus 3-4 5 4,5

Potamogeton acutifolius 3 6

Myriophyllum spicatum 2,5-3-4 7 not rich 3,0

Hottonia palustris 2-3 4 not high

Trophic level indication of standing waters by hydrophytes (literature)

N* = Ellenberg et al. (1991)

I° = Melzer (1988)

14

level

Lem

na gibba

Lem

na minor

Lem

na trisulca

Spirod.

polyrhiza

Cer.

submersum

Cer. dem

ersum

Utric. vulgaris

Fadengrünalgen

Riccia fluitans

Nuphar luta

Nym

phaea alba

Pol. am

phibium

Pol. natans

Pol. crispus

Pot. acutifolius

Chara fragilis

4,5 Cer. submersum

Fadengrünalgen

25-75

25-75

25 25 1

4,0 Lemna gibba 25-100 25 5

4,0 Cer. submersum 50-100 25 50 10 10 25 5

3,5 Lemna minor Spirodela polyrhiza

50-100 0-100

10 10

3,5 Wolffia arrhiza 25-75 50 50 50 10 25 5

3,5 Cer. submersum 25-50 25 25 5 10 10 10

3,0 Cer. submersum 10-25 25 50 25 25 5 25 25 25 50 10

3,0 Lemna minor Spirodela polyrhiza

5-50

0-50

25 10 10

3,0 Myr. Spicatum Nuphar lutea

5-50

5-25

50 25 10 10 10

3,0 Ran. aquatilis 10-75 10 25 10

3,0 Hottonia palustris 10-50 25

Tro-phic

Dominant species *coverage [%]

Accompanying species*max. coverage [%]

Preliminary trophic level indikation of potholes by hydrophytes

*Coverage in % of whole water area with litoral charakter (maximum May to September)

15

y = -0,0395x + 3,8965

R2 = 0,14330

1

2

3

4

5

0 5 10 15 20

Share of hydrophytes

Tro

ph

ic le

ve

l

Correlation between matter loadings and biodiversity of macrophytes

y = -0,0005x2 - 0,0152x + 3,9785

R2 = 0,35260

1

2

3

4

5

0 10 20 30 40

Share of helophytes

Tro

ph

ic le

ve

l

Problem: Shortage of weak eutrophic reference sites in the agricultural landscape

n = 32; r =0,59; significant p < 0,001n = 32; r = 0,64; significant p < 0,001

n = 32; r = 0,38; significant p < 0,02n = 32; r = 0,19; nicht significant

y = -0,0101x2 + 0,0875x + 3,908

R2 = 0,4068-10

-5

0

5

10

0 10 20 30 40

Shortage ofl helophytes

Ma

tte

r lo

ad

ing

dis

po

sit

ion

y = -0,1551x + 3,2373

R2 = 0,0368-10

-5

0

5

10

0 5 10 15 20

Share of hydrophytes

Ma

tte

r lo

ad

ing

dis

po

sit

ion

16

Correlation between water quality and surface sediment pollution

n = 22; r = 0,76; significant p < 0,001

n = 22; r = 0,66; significant p < 0,005

n = 22; r = 0,54; significant p < 0,01

Problems:

• influence of soil erosion and wet-dry cycle on mud formation (silicate muds)

• shortage of weak eutrophic reference sites in the agricultural landscape

1mg/kg = 0,0001 %

R2 = 0,52

0

0,02

0,04

0,06

0,08

0,1

0,12

0,14

0,16

0,18

0,2

2,5 2,7 2,9 3,1 3,3 3,5 3,7 3,9 4,1 4,3 4,5

Water quality (Trophic Level)

TP

[%

dry

mat

ter]

1mg/kg = 0,0001 %

R2 = 0,26

0

0,2

0,4

0,6

0,8

1

1,2

1,4

2,5 2,7 2,9 3,1 3,3 3,5 3,7 3,9 4,1 4,3 4,5

Water Quality (Trophic Level)

TN

[%

dry

ma

tte

r]

R2 = 0,40

0

5

10

15

20

25

2,5 2,7 2,9 3,1 3,3 3,5 3,7 3,9 4,1 4,3 4,5

Water Quality (Trophic Level)

C/N

(sed

imen

t 0-2

0 cm

)

17

1 2 3 4 3 1

Influence of runoff in winter period on trophic level of potholes in agricultural landscapes with middle to high matter loading disposition

n = 18

2,0

2,5

3,0

3,5

4,0

4,5

1993 1994 1995 1996 1997 1998

Wate

r Q

uality

(Tro

ph

ic L

evel)

MV-spring MV-Summer

1 = low runoff 3 = snowmelt, high runoff, frozen soil2 = rain, high runoff, soil not frozen 4 = snow/rain, thawing soil, middle runoff