Accesso libero

The simplistic nitrogen input and output balance in Lake Łebsko – case study

Roman Cieśliński
Roman Cieśliński
   | 22 set 2016
Oceanological and Hydrobiological Studies's Cover Image
INFORMAZIONI SU QUESTO ARTICOLO
Articolo precedente
Articolo Successivo
Cita
Article Category: Original research paper
Pubblicato online: 22 set 2016
Pagine: 424 - 443
Ricevuto: 07 ott 2015
Accettato: 11 gen 2016
DOI: https://doi.org/10.1515/ohs-2016-0037
Parole chiave
© 2016 Faculty of Oceanography and Geography, University of Gdańsk, Poland. All rights reserved
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Figure 1

Location of Lake Łebsko in the Polish coastal zone and location of measurement sites
Location of Lake Łebsko in the Polish coastal zone and location of measurement sites

Figure 2

Discharge in the Łeba Canal between June 2008 and October 2010. Negative values indicate the sea-lake flow direction, while positive values indicate the lake-sea flow.
Discharge in the Łeba Canal between June 2008 and October 2010. Negative values indicate the sea-lake flow direction, while positive values indicate the lake-sea flow.

Figure 3

Inflow of surface water into Lake Łebsko
Inflow of surface water into Lake Łebsko

Figure 4

Mean concentrations of ammonium in Lake Łebsko at selected sampling sites
Mean concentrations of ammonium in Lake Łebsko at selected sampling sites

Figure 5

Changes in the concentration of total nitrogen in Lake Łebsko – two sampling sites. Two sampling sites: Site No. 4 -located in the southern part of the lake; Site No. 8 – located in the northern part of the lake
Changes in the concentration of total nitrogen in Lake Łebsko – two sampling sites. Two sampling sites: Site No. 4 -located in the southern part of the lake; Site No. 8 – located in the northern part of the lake

Figure 6

Changes in the concentration of nitrates in Lake Łebsko. Two sampling sites: Site No. 4 – located in the southern part of the lake; Site No. 8 – located in the northern part of the lake
Changes in the concentration of nitrates in Lake Łebsko. Two sampling sites: Site No. 4 – located in the southern part of the lake; Site No. 8 – located in the northern part of the lake

Figure 7

Total nitrogen load supplied to Lake Łebsko by rivers and canals in 2008-2010
Total nitrogen load supplied to Lake Łebsko by rivers and canals in 2008-2010

Figure 8

Percentage contribution of selected sources of the total nitrogen load supplied to Lake Łebsko in 2009
Percentage contribution of selected sources of the total nitrogen load supplied to Lake Łebsko in 2009

Figure 9

Monthly inputs and outputs of total nitrogen [tons month-1] in Lake Łebsko in 2008-2010
Monthly inputs and outputs of total nitrogen [tons month-1] in Lake Łebsko in 2008-2010

Figure 10

Monthly size of Nret and ΔN in Lake Łebsko in 2008-2010
Monthly size of Nret and ΔN in Lake Łebsko in 2008-2010

Hypothetical migration of nutrient material into Lake Łebsko from its drainage basin (kg km2 yr-1) based on research by Kajak (1983)

Type of use Nitrogen
Forests 258.2
Arable land 2295.4
Meadows and pastures 4032.8
Total 6586.4

Concentrations of nutrient substances in Lake Łebsko in the study period

Indicator [unit] Minimum Maximum Average
Total nitrogen [mg N dm-3] 0.31 3.08 1.25
Nitrates [mg NO3- dm-3] 0.05 1.94 0.58
Ammonium [mg NH4+ dm-3] 0.90 3.90 2.20

Mean monthly total nitrogen load, nitrate load and ammonium loads (tons per month) for watercourses flowing into Lake Łebsko in 2008-2010

Name 2008 2009 2010
total nitrogen load
Łeba 44.27 35.39 53.55
Pustynka 8.18 9.81 12.64
Other courses 7.27 4.84 6.03
nitrate load
Łeba 35.41 29.64 36.77
Pustynka 6.36 7.82 7.59
Other courses 4.69 2.65 3.16
ammonium loads
Łeba 64.84 51.19 62.43
Pustynka 7.91 7.27 9.18
Other courses 8.83 4.81 6.65

Mean concentrations of nutrient substances in lake surface water, lake bottom water, and lake interstitial water for Lake Łebsko from June 2008 to October 2010

Indicator [unit] Layer Point
1 2 5 6 8 3 4 7
Total nitrogen [mg N dm-3] Surface 1.36 1.11 1.21 1.34 1.12 1.33 1.39 1.33
Near-bottom 1.34 1.16 1.28 1.40 1.16 1.39 1.41 1.41
Interstitial 1.77 1.64 1.49 2.13 1.67 1.95 1.76 1.62
Nitrates [mg NO3- dm-3] Surface 0.67 0.53 0.67 0.69 0.50 0.85 0.68 0.56
Near-bottom 0.67 0.54 0.71 0.64 0.59 0.79 0.79 0.65
Interstitial 0.79 0.72 0.77 0.86 0.74 0.96 0.78 0.80
Ammonium [mg NH4+ dm-3] Surface 2.0 1.8 3.0 1.5 1.3 3.4 3.6 1.6
Near-bottom 2.1 1.8 3.2 1.6 1.5 3.5 3.6 1.7
Interstitial 2.2 1.9 3.3 1.9 1.6 3.8 3.8 1.9

Mean loads of nitrogen compounds (tons per month) entering and leaving Lake Łebsko

Ion Inflow from the catchment Outflow from the lake Odds % amount of load remaining in the lake Inflow from the sea
Ntotal 60.03 41.16 18.87 31.43 36.01
N-NO3 44.20 16.50 27.70 62.50 30.16
N-NH4 72.86 67.02 5.84 8.02 82.56

Size of total nitrogen loads discharged into Lake Łebsko in 2009 via various routes

Name Annual load in tons
Łeba 424.72
Pustynka 117.70
Other courses 58.07
Runoff 47.00
Baltic Sea 87.81
Precipitation 104.30
Total 839.60
Outflow to the sea 304.65

Mean concentrations of nutrient substances in river and stream water reaching Lake Łebsko between June 2008 and October 2010

Name Total nitrogen[mg N dm-3] Nitrates[mg NO3- dm-3] Ammonium[mg NH4+ dm-3]
Gardno – Łebsko Canal 1.44 0.69 2.48
Łupawa – Łebsko Canal 2.04 0.89 2.66
Łeba 1.85 1.41 2.25
Old Łeba 1.92 1.02 2.28
Pustynka 2.37 1.64 2.95
Canal Żarnowski 3.20 1.29 3.16
Canal Żelazo 1.64 1.18 2.67
Canal Witkowo 1.85 1.05 2.44
Canal Izbicki 1.97 1.03 3.15
Lake Łebsko 1.27 0.64 2.20
eISSN:
1897-3191
Lingua:
Inglese
Frequenza di pubblicazione:
4 volte all'anno
Argomenti della rivista:
Chemistry, other, Geosciences, Life Sciences
Feed RSS della rivista