C n p fluxes in the coastal zone
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C N P Fluxes in the Coastal Zone. The LOICZ Approach to Budgeting and Global Extrapolation. Easier to quantify globally than locally: Via global loading budgets; Little understanding of distribution or controls. Function of biota and inorganic reactions; Function of environmental conditions:

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C n p fluxes in the coastal zone

C N P Fluxes in the Coastal Zone

The LOICZ Approach to Budgeting and Global Extrapolation


What is the role of the coastal ocean in global cnp cycles

Easier to quantify globally than locally:

Via global loading budgets;

Little understanding of distribution or controls.

Function of biota and inorganic reactions;

Function of environmental conditions:

F(land inputs, oceanic exchanges);

F(human pressures);

F(regional, global environmental change).

An environmentally important question that can be approached via geochemical reasoning.

What is the role of the coastal ocean in global CNP cycles?


General background

General Background


Global elevation

Global Elevation

Only a small portion lies in the “LOICZ domain.”


Coastal zone 200 to 200 m

Coastal Zone (+200 to –200 m)

This domain is nominally + 200 m to -200 meters, orabout 18% of global area.


Coastal ocean 0 to 200 m

Coastal Ocean (0 to –200 m)

The coastal ocean, being budgeted by LOICZ, is about 5% of global area.


The global coastal ocean a narrow uneven chemically reactive ribbon

LAND

OCEAN

The Global Coastal Ocean: A Narrow, Uneven, Chemically Reactive “Ribbon”

This ribbon is ~ 500,000 km long and averages about 50 km in width.

Most materials entering the ocean from land pass through this ribbon.

Most net biogeochemical reaction is thought to occur in the landward, estuarine, portion of the ribbon.


The global coastal ocean a narrow uneven chemically reactive ribbon1

LAND

OCEAN

The Global Coastal Ocean: A Narrow, Uneven, Chemically Reactive “Ribbon”

  • LOICZ covers only ~5% of the global ocean, but:

    • 18-33% of the global PP

    • ~83% of POM mineralisation

    • Preservation of ~87% of ocean POM

    • Transit for major part of the elements controling Ocean PP (N, P, Si, Fe, etc)


Loicz and igbp

IGBP is the “International Geosphere-Biosphere Programme.”

Part of ICSU, the International Council of Scientific Unions

LOICZ is “Land-Ocean Interactions in the Coastal Zone.”

A key project element of IGBP

LOICZ and IGBP


Igbp international geosphere biosphere programme

IGBP aim --To describe and understand the interactive physical, chemical and biological processes that regulate the Earth System, the environment provided for life, the changes occurring in the system, and the influences of human actions.

LOICZ aim -- About the same as IGBP aim —for the coastal zone.

IGBP:International Geosphere-Biosphere Programme


Alphabet soup of the igbp

JGOFSJoint Global Ocean Flux Studies

IGACInternational Global Atmospheric Chemistry

GCTEGlobal Change and Terrestrial Ecosystems

BAHCBiospheric Aspects of the Hydrological Cycle

PAGESPast Global Change

LOICZLand-Ocean Interactions in the Coastal Zone

LUCCLand Use and Cover Change

GLOBEC Global Ocean Ecosystem Dynamics__________________________________________________

GAIMGlobal Analysis, Integration and Modelling

STARTSystem for Analysis, Research, and Training

DIS Data and Information System

Alphabet Soup of the IGBP


C n p fluxes in the coastal zone

Stephen Smith [email protected]

Fred Wulff [email protected]

Vilma Dupra [email protected]

Dennis [email protected]

Victor [email protected]

 Malou McGlone [email protected]

 Laura David [email protected]

LOICZ International Project Office [email protected]

 Biogeochemical Modeling Web Page http://data.ecology.su.se/MNODE/


Loicz budgeting background

LOICZBudgeting Background


Develop a globally applicable method of flux estimation

Ability to work with secondary data;

Minimal data requirements;

Widely applicable, uniform methodology;

Robust;

Informative about processes of CNP flux.

Develop a “Globally Applicable” Method of Flux Estimation


Loicz budgeting procedure

LOICZ Budgeting Procedure

  • Conservation of mass is one of the most fundamental concepts of ecology and geochemistry.


Water salt and stoichiometrically linked nutrient budgets

Water and salt budgets are used to estimate water exchange in coastal systems.

Departure of nutrient budgets from conservative behavior measures “system biogeochemical fluxes.”

Nonconservative DIP flux is assumed proportional to (primary production – respiration).

Mismatch from “Redfield expectations” for DIP and DIN flux is assumed proportional to (nitrogen fixation – denitrification).

Water, Salt, and “Stoichiometrically Linked” Nutrient Budgets


Water and salt budgets

Salt budget

Net flows known.

Mixing (VX) conserves salt content.

Water budget

Freshwater flows known.

System residual flow (VR) conserves volume.

Water and Salt Budgets


Nutrient budgets

Calculations based on simple system stoichiometry

Assume Redfield C:N:P ratio (106:16:1)

(production - respiration) = -106 x DIP

(Nitrogen fixation - denitrification) = DINobs - 16 x DIP

Nutrient (Y) budgets

Internal dissolved nutrient net source or sink (Y) to conserve Y.

Nutrient Budgets


Loicz strategy

Develop a global inventory of these budgets.

Guidelines, a tutorial, and individual site budgets at http://nest.su.se/mnode/

Use “typology” (classification) techniques to extrapolate from budgeted sites to global coastal zone.

LOICZ Strategy


Loicz budgeting research

New, or “primary,” data collection is not a primary aim of LOICZ budgeting research.

There is heavy reliance on available secondary data to insure widespread (“global”) coverage.

Workshops and information sharing via the World Wide Web are the major tools for adding information to the LOICZ budgeting data base.

Funding for workshops has come from UNEP/GEF, LOICZ, WOTRO, local sponsorship.

Develop analytical tools to assist in budgeting.

LOICZ Budgeting Research


Loicz budget sites to date

LOICZ Budget Sites to Date

>100 sites so far; > 200 sites desired.


Latitude longitude of budget sites

Latitude, Longitude of Budget Sites

  • Present site distribution

  • Poor cover at high latitudes (N & S).

  • Poor cover from 10N to 15S.

  • Poor cover in Africa.

  • S. Asia sites not yet posted.


Nutrient load v latitude

Nutrient Load v Latitude

  • Load variation most obvious with DIP.

  • High loads near 15N are in SE Asia.

  • High loads near 30S are in Australia


Internal nutrient flux v latitude

Internal Nutrient Flux v Latitude

  • DIP response to load may differ in the N and S hemispheres.

  • DIN response to load seems weaker than DDIP.


Dip d din v dip load

DIP, DDIN v DIP Load

  • DIP and DDIN both increase (+ or -) at high DIP loads.

  • Responses more prominent for DIP than for DIN.


Dip d din v din load

DIP, DDIN v DIN Load

  • No clear effect of DIN load on DDIP.

  • DIN appears to become negative at high DIN load.


Net ecosystem metabolism production respiration

Net Ecosystem Metabolism(production – respiration)

  • Remember: Rates are apparent, based on stoichiometric assumptions.

  • No clear overall trend; most values cluster near 0.

  • Extreme values (beyond  10) are questionable.


Nitrogen fixation denitrification

(Nitrogen Fixation – Denitrification)

  • Although values cluster near 0, clear dominance of apparent denitrification.

  • Apparent N fixation >5 seems too high.


Some cautionary notes

Individual budgets may suffer from data quality or other analytical problems.

Stoichiometry is “apparent,” and not always reliable.

Simple averaging of budgets is not a legitimate estimate of global average performance; the coastal zone is too heterogeneous and sampling is too biased for such averaging.

Also, system size, or relative geographic importance, not accounted for in simple averaging.

“Upscaling” must take these factors into account.

Some Cautionary Notes


Loicz biogeochemical budgeting procedures and examples

LOICZ Biogeochemical Budgeting Procedures and Examples


Introduction

INTRODUCTION


Material budget

Material budget

LOICZ budgeting assumes that

materials are conserved. The

difference ([sources – sinks])

of imported (inputs) and

exported (outputs) materials

may be explained by the processes

within the system.

Note: Details of the LOICZ

biogeochemical budgeting are

discussed at http://www.nioz.nl/

loicz and in Gordon et al., 1996.

outputs

System

inputs

Net Sources

or Sinks

[sources – sinks] = outputs - inputs


Three parts of the loicz budget approach

Estimate conservative material fluxes (i.e. water and salt);

Calculate non-conservative nutrient fluxes; and

Infer apparent net system biogeochemical performance from non-conservative nutrient fluxes.

Three parts of the LOICZ budget approach


Outline of the procedure

Define the physical boundaries of the system of interest;

Calculate water and salt balance;

Estimate nutrient balance; and

Derive the apparent net biogeochemical processes.

Outline of the procedure


Procedures and examples

PROCEDURES AND EXAMPLES


Locate system of interest

Locate system of interest

Philippine Coastlines

Resolution (1:250,000)

http://crusty.er.usgs.gov//coast/


Define boundary of the budget

Define boundary of the budget

Subic Bay, Philippines

Map from Microsoft Encarta


Variables required

System area and volume;

River runoff, precipitation, evaporation;

Salinity gradient;

Nutrient loads;

Dissolved inorganic phosphorus (DIP);

Dissolved inorganic nitrogen (DIN);

DOP, DON (if available); and

DIC (if available).

Variables required


Simple single box well mixed system

SIMPLE SINGLE BOX(well-mixed system)


Calculate water balance

Calculate water balance

dVsyst/dt = VQ+VP+VE+VG+VO+VR

at steady state:

VR = -(VQ+VP+VE+VG+VO)


Water balance illustration

Water balance illustration

VE = 680

VP = 1,160

VR = -1,360

Vsyst = 6 x 109 m3

Asyst = 324 x 106 m2

VQ = 870

VG = 10

VO = 0

(assumed)

Fluxes in 106 m3 yr-1

VR = -(VQ+VP+VE+VG+VO)

VR = -(870+1,160-680+10+0)

VR = -1,360 x 106 m3 yr-1


Calculate salt balance

Calculate salt balance

Eliminate terms that are equal to or near 0.

VX = (-VRSR - VGSG )/(SOcn – SSyst)


Salt balance to calculate v x and

Salt balance to calculateVXand 

VR = -1,360

VRSR = -41,480

SQ = 0 psu

VQSQ = 0

Vsyst = 6 x 109 m3

Ssyst = 27.0 psu

SOcn = 34.0 psu

SR = (SOcn+ SSyst)/2 SR = 30.5 psu

t = 300 days

SG = 6.0 psu

VGSG = 60

VX(SOcn- SSyst) =

-VRSR -VGSG = 41,420

VX = 5,917

Fluxes in 106 psu-m3 yr-1

  • = VSyst/(VX + |VR|)

VX = (-VRSR -VGSG)/(SOcn – SSyst)

  • = 6,000/(5,917 + 1,360)

VX = (41,480 - 60 )/(34.0 – 27.0)

  • = 0.8 yr  300 days

VX = 5,917 x 106 m3 yr-1


Calculate non conservative nutrient fluxes

Calculate non-conservative nutrient fluxes

d(VY)/dt = VQYQ + VGYG +VOYO +VPYP + VEYE + VRYR + VX(Yocn - Ysyst) + Y


Schematic for a single box estuary

Schematic for a single-box estuary

Residual flux

(VRYR);

YR = (YSyst+YOcn)/2

River discharge

(VQYQ)

System,YSyst

(DY)

Ocean, YOcn

Groundwater (VGYG)

Mixing flux

(VXYX);

YX = (YOcn-YSyst)

Other sources

(VOYO)

d(VY)/dt = VQYQ + VGYG + VOYO +VPYP + VEYE + VRYR + VX(Yocn - Ysyst) + Y

Eliminate terms that are equal to or near 0.

0 = VQYQ + VGYG + VOYO + VRYR + VX(Yocn - Ysyst) + Y

Y = -VQYQ - VGYG - VOYO - VRYR - VX(Yocn - Ysyst)


Dip balance illustration

Y = - VRYR - VX(Yocn - Ysyst) – VQYQ – VGYG - VOYO

DIP = - VRDIPR - VX(DIPocn - DIPsyst) – VQDIPQ - VGDIPG - VODIPO

DIP = 544 - 2,367 – 261 –1 - 30 = -2,115 x 103 mole yr-1

DIP balance illustration

VRDIPR = -544

DIPQ = 0.3

VQDIPQ = 261

DIPsyst = 0.2 mM

DIPOcn = 0.6 mM

DIPR = 0.4 mM

DDIP = -2,115

DIPG = 0.1

VGDIPG = 1

VODIPO = 30

(other sources,

e.g., waste, aquaculture)

VX(DIPOcn- DIPSyst) = 2,367

Fluxes in 103 mole yr-1

DIN = +15,780 x 103 mole yr-1 (calculated the same as DIP)


Stochiometic calculations

STOCHIOMETIC CALCULATIONS


Stoichiometric linkage of the non conservative d y s

Stoichiometric linkage of the non-conservative (DY’s)

106CO2 + 16H+ + 16NO3- + H3PO4 + 122H2O

(CH2O)106(NH3)16H3PO4 + 138O2

Redfield Equation

(p-r)or net ecosystem metabolism, NEM

= -DDIPx106(C:P)

(nfix-denit)= DINobs - DINexp

= DINobs - DIPx16(N:P)

Where: (C:P) ratio is 106:1 and

(N:P) ratio is 16:1 (Redfield ratio)

Note:Redfield C:N:P is a good approximation where

local C:N:P is absent.


Stoichiometric calculations

(p-r)= -DDIPx106(C:P)

= -(-2,115) x 106

= +224,190 x 103 mole yr-1

= +2 mmol m-2 day-1

(nfix-denit)= DINobs - DINexp

= DINobs - DIPx16(N:P)

= 15,780 – (-2,115 x 16)

= +49,620 x 103 mole yr-1

= +0.4 mmol m-2 day-1

Stoichiometric calculations

Note:Derived net processes are apparent net performance

of the system. Other non-biological processes may be responsible

for the sum of the uptake or release of the DY’s.


Two layer box stratified system

TWO-LAYER BOX(STRATIFIED SYSTEM)


C n p fluxes in the coastal zone

Stratified system (two-layer box model)


Two layer water and salt budget model

Two-layer water and salt budget model

VE

VP

VQ (Runoff)

VQSQ

VSurf (Surface Flow)

VSurfSSyst-s

Upper Layer

SSyst-s

VDeep’ (Entrainment)

VDeep’SSyst-d

VZ (Volume Mixing)

VZ(SSyst-d-SSyst-s)

SOcn-d

Lower Layer

SSyst-d

VDeep (Deep Water Flow)

VDeepSOcn-d

VQ +VP + VE + VSurf + VDeep' = 0

VQSQ + VSurfSSyst-s + VDeep‘SSyst-d + VZ(SSyst-d - SSyst-s) = 0


Two layer budget equations

VQ + VSurf + VDeep = 0

VDeep = VR'(SSyst-s)/(SSyst-s-SOcn-d )

VR’ = -VQ -VP -VE

VZ = VDeep(SOcn-d -SSyst-d)/(SSyst-d-SSyst-s)

 = VSyst/(|VSurf|)

Two-layer budget equations

Note: Visit LOICZ website

<http://data.ecology.su.se/MNODE/Methods/TWOLAYER.HTM>

for detailed derivation of the above equations.


Water and salt budget for stratified system illustration

Water and salt budget for stratified system (illustration)

VE= 0

VP = 4

SQ = 0.1 psu

VQ = 10

VQSQ = 1

Water flux

in 106 m3 day-1

and salt fluxin

106 psu-m3 day-1.

VSurf = 95

VSurfSSyst-s= 2,650

Aysen Sound

Upper Layer

Vsyst-s = 11.8x109 m3

SSyst-s= 27.9 psu

t = 89 days

VDeep’ = 81

VDeep’SSyst-d = 2,527

VZ = 37

VZ(SSyst-d-SSyst-s) = 122

SOcn-d = 32.7 psu

Lower Layer

VSyst-d = 55.0x109 m3

SSyst-d = 31.2 psu

t = 466 days

VDeep = 81

VDeepSOcn-d = 2,649

tSyst = 703 days


Two layer nutrient budget model

Two-layer nutrient budget model

Upper layer residual flux

(VSurfYSyst-s)

River discharge

(VQYQ)

Upper Layer

YSyst-s

DYSyst-s

Ocean lower

Layer, Yocn-d

Entrainment flux(VDeep’YSyst-d)

Mixing flux

(VZ(YSyst-d-Ysyst-s))

Lower Layer

Ysyst-d

DYSyst-d

Lower layer residual flux

(VDeepYOcn-d)

DYSyst = (DYSyst-s+DYSyst-d)


Dip balance for stratified system illustration

DIP balance for stratified system(illustration)

DIPQ = 0.1mM

VQ = 10

VQDIPQ = 1

VSurf = 95

VSurfDIPSyst-s= 143

Fluxes in

103 mole day-1.

Aysen Sound

Upper Layer

DIPSyst-s= 1.5 mM

DDIP = -3

VDeep’ = 81

VDeep’DIPSyst-d = 138

VZ = 37

VZ(DIPSyst-d-DIPSyst-s)=7

DIPOcn-d = 1.4 mM

Lower Layer

DIPSyst-d = 1.7 mM

DDIP = +32

VDeep = 81

VDeepDIPOcn-d = 113

DDIPSyst = +29


Complex systems in series

COMPLEX SYSTEMS IN SERIES


Pelorus sound new zealand

Pelorus Sound, New Zealand

N

Lower

Pelorus

Tawhitinui

Reach

Upper

Pelorus

Kenepuru

Arm

Havelock

Arm

Red dashed lines show segmentation of the system.


Schematic of systems in series

Schematic of systems in series

Segmentation for Pelorus Sound Budget.


Water balance for stratified systems in series

Water balance for stratified systems in series

Complex system like

Pelorus Sound can be

budgeted as a combination

of single-layer and two-layer

segments.


Temporal and spatial variation

TEMPORAL AND SPATIALVARIATION


Implication of temporal and spatial variation

Products of the averages

= 5.5(39)

= 215

Averages of the products

= (15 + 30 + 50 +0)/4

= 24

Implication of temporal and spatial variation

Systems should be segmented spatially or temporally if there is

significant spatial and temporal variation. The algebraic reason

is that in general the product of averages does not equal the average

of the products. Visit the web site <http://data.ecology.su.se/MNODE/

Methods/spattemp.htm> for a more detailed explanation of this point.

X = 15, 6, 1, 0Y = 1, 5, 50, 100


Temporal patterns of the variables

Temporal patterns of the variables

The average of the nutrient

flux does not equal to the product of the annual average flow and concentration. The budget based on the annual average data is simply not as accurate as the budget on the

average fluxes.

Temporal gradients

of variables will give clue to seasonal division of the data


Gracias

Gracias


Loicz cabaret

LOICZ-CABARET

L.T. David 1, S.V. Smith 2, J. de Leon 1, C. Villanoy 1,V.C. Dupra 1,2 , and F. Wulff 3

1Marine Science Institute, University of the Philippines, Diliman, Quezon City 1101, Philippines

2School of Ocean and Earth Science and Technology, Honolulu, Hawaii, USA

3Department of Systems Ecology, Stockholm University, Stockholm, Sweden

Computer Assisted Budget Analysis for Research, Education, and Training


C n p fluxes in the coastal zone

Statement of Purpose

The Computer Assisted Budget Analysis for Research, Education, and Training or LOICZ-CABARET was designed to simplify the process of calculations in applying the LOICZ approach to biogeochemical budget calculations.

This current version can assist in the calculation of the water, salt, and nutrient budget of any single-box or multi-box single-layer or multi-layer system by seasons or monthly. It can also assist in the calculation of the area and volume of a system in its entirely or treated as sub-systems through its on-screen digitization. Finally, to circumvent observed complications of previous users in unit conversions, the LOICZ-CABARET automatically transforms units into m3/yr for easier comparison between systems. Results are displayed in the familiar LOICZ box-diagram format.

Additional improvements are periodically posted at the LOICZ webpage www.nioz.nl/loicz

For questions and suggestion, contact [email protected]


C n p fluxes in the coastal zone

The program can be downloaded from the LOICZ webpage as an executable ZIP file. It is best if the downloaded file is placed and unzipped inside a blank folder. All future working files must reside in this folder for the program to work.

To unzip, just double click the executable zip. Run program by double-clicking on cabaret.exe

The program should work in windows 95/97/2000 and NT.


C n p fluxes in the coastal zone

FLOW CHART

Sequentially fill in the necessary data. To help guide users through the program, a flow chart can be accessed at any time by clicking on the menu choice named FLOWCHART.

Close the flowchart window by clicking DONE.


C n p fluxes in the coastal zone

ALPHA/PERSONAL

In order to be duly recognized as a contributor, make sure to fill in the Contact Person Information Window.

Note that the two buttons at the bottom allows the user to go back to the previous window (B) or forward to the next sequential window (N)


C n p fluxes in the coastal zone

ALPHA/DESCRIPTION

  • Site description goes inside this window. It is necessary to enter the following fields:

  • ESTUARY NAME

  • COUNTRY

  • THE NORTH, SOUTH, EAST, WEST BORDERS OF THE SYSTEM

  • NO. OF SEASONS & THE START AND END MONTHS OF EACH SEASON


C n p fluxes in the coastal zone

CALIBRATE

Choose the type of system

The No. of boxes

The No. of layers

The area per box

If the area is unknown, LOICZ-CABARET also allows for the estimation of the area using the on-screen digitization.

To use this feature you must have a bmp image of your system.

Type in the length of your calibration bar found in most maps or use the latitude lines and then click on the MAP button.


C n p fluxes in the coastal zone

BMP OF MAP

A small window asking for the bmp file name opens when you click on MAP.

The map image then opens.

Click the ends of the calibration bar then click DONE.


C n p fluxes in the coastal zone

ESTIMATING BOX AREA

To estimate the area per box, double-click on the corresponding box area.

This will once again open the bmp image of your system.

Digitize the box area on-screen. The box area polygon is designed to automatically close upon clicking of DONE.


C n p fluxes in the coastal zone

ALPHA/MATERIALS

  • The water, salt and nutrient data are typed in this window.

  • The minimum fields to be filled are the following:

  • Layer depth

  • At least one freshwater flow

  • At least the salt and nutrient concentration of the outer box and the system box

  • This should be done per box and per layer.

  • Afterwards, click BUILDHTML


C n p fluxes in the coastal zone

RESULT - WATER AND SALT BALANCE

Results can be viewed using any web-browser.

Make sure to re-load the page after every edit.


C n p fluxes in the coastal zone

RESULT - PHOSPHATE & NITRATE BALANCE


C n p fluxes in the coastal zone

VISION

It is hoped that LOICZ-CABARET will not only encourage the users to contribute to the LOICZ endeavor but also experiment with the forcing functions and response sensitivity of their systems. Finally, LOICZ-CABARET is also envisioned to be used as a teaching tool in estuaries and coastal lagoon studies.


C n p fluxes in the coastal zone

Estimationof Waste Load

Marine Science Institute

University of the Philippines


C n p fluxes in the coastal zone

Precipitation

Evaporation

Coastal Water Body

Residualflux

Runoff

Groundwater

Sewage/Waste

Mixingflux


C n p fluxes in the coastal zone

Sources ofWaste (human activity)

household activities

livestock

agriculture

urban runoff

aquaculture

manufacturing


C n p fluxes in the coastal zone

Steps in the Calculation of Waste Load

1. Identify relevant human activities

households - solid waste, domestic sewage, detergent

livestock - piggery, poultry, cattle

agriculture - soil erosion, fertilizer runoff

urban runoff - unsewered areas

aquaculture - prawns, fish

manufacturing - food, textiles, chemicals


C n p fluxes in the coastal zone

2. Determine thelevelof each human activity

from government statistics, preferably at local level

household - size of the population

livestock - no of pig, chicken, cow

aquaculture - tons of prawn, fish

urban runoff - urban area

agriculture - tons of soil eroded


C n p fluxes in the coastal zone

3. Approximate TN and TP (in effluent discharge)

TN =activity level x discharge coefficient

TP =activity level x discharge coefficient

T


C n p fluxes in the coastal zone

The discharge coefficients for various human activities

are given in the following spreadsheet.

This spreadsheet calculates TN and TP load in waste generated by various human activities. Knowledge of the activities relevant to the coastal area is necessary and the only input needed in the spreadsheet would be the level of the waste generating activity (fill in white cells).


C n p fluxes in the coastal zone

Sources of Discharge Coefficients


C n p fluxes in the coastal zone

TN and TP (in the spreadsheet) are approximated using the following calculations.


C n p fluxes in the coastal zone

TN =activity level x discharge coefficient

Ex. for Domestic Sewage

activity level = 2000 persons

discharge coefficient = 4 kgN/person/yr

TN = 4 kgN/person/yr x 2000 persons

TN = 8000 kgN/yr

TP =activity level x discharge coefficient

discharge coefficient = 1 kgP/person/yr

TP = 1 kgP/person/yr x 2000 persons

TP = 2000 kgP/yr


C n p fluxes in the coastal zone

If only BOD and COD data are available, TN and TP can be approximated using the following ratios*

TN/BOD = 0.5

TP/BOD = 0.042

COD/BOD = 2.6

Ex if available data is BOD at 5 mg/L

TN = 5 mg/L x 0.5 = 2.5 mg/L

Ex if available data is COD at 5 mg/L

TN =5 mg/L x 1/26 (BOD/COD) x 0.5

= 1 mg/L


C n p fluxes in the coastal zone

The previous spreadsheet also approximates DIN and DIP. The following calculations illustrate how this is done.


C n p fluxes in the coastal zone

4. Calculate DIN and DIP in the effluent discharge

Assumption: 25% of waste enter the bay

Use stoichiometric ratio*

DIN/TN = 0.38

DIP/TP =0.5

DIN = TN÷atomic wt NxDIN/TNx25%

DIN = 8000 kgN/yr÷14 g/molex0.38x0.25

DIN = 54,000 moles/yr

DIP = TP÷atomic wt PxDIP/TPx25%

DIP = 2000 kgP/yr÷31 g/molex0.5x0.25

DIP = 8,000moles/yr


C n p fluxes in the coastal zone

The following N and P budgets of a Philippine bay (LINGAYEN GULF) are given to illustrate how waste is quantified and show that this is an important input to the system.


C n p fluxes in the coastal zone

NITROGEN AND PHOSPHORUS BUDGETS

FOR LINGAYEN GULF


C n p fluxes in the coastal zone

Lingayen Gulf

Manila Bay

South China Sea


C n p fluxes in the coastal zone

Upper Gulf

1764 km2, 81 km3

Bolinao

126 km2, 0.3 km3

Nearshore

210 km2, 3.2 km3

Lingayen Gulf divided into three boxes


C n p fluxes in the coastal zone

LINGAYEN GULF

Water Budget (fluxes in 109m3/yr)

VR = 11

VP =4

VE = 4

VP = 0.3

VE = 0.3

Ocean

VQ = 2

VG = 0.4

VQ = 8

VG = 0.2

VQ = 0.2

VG = 0.7

Upper Gulf

1764 km2, 81 km3

Bolinao

126 km2,0.3 km3

VR = 1

VR = 8

Nearshore

210 km2, 3.2 km3

VP = 0.5

VE = 0.4


C n p fluxes in the coastal zone

LINGAYEN GULF

Salt Budget (salt fluxes in 109 psu-m3/yr)

VRSR = 376 VX = 940

Ocean

S3 = 34.4

Upper Gulf

1764 km2, 81 km3

VRSR = 34

Bolinao

126 km2, 0.3 km3

S1B = 33.5

S2 = 34.0

 = 2 days

 = 27 days

VX = 68

VRSR = 260

VX = 87

Nearshore

210 km2, 3.2 km3

S1N = 31

 = 12 days


C n p fluxes in the coastal zone

Table 1. Effluents produced by economic activities in

Lingayen Gulf (in 106 mole yr-1).


C n p fluxes in the coastal zone

LINGAYEN GULF

DIP Budget (fluxes in 106 moles/yr)

DIP3 = 0.0µM

VRDIPR = 1

Ocean

VXDIPX = 94

VQDIPQ = 1

VQDIPQ = 1

Upper Gulf

VRDIPR = 0

VODIPO = 35

Bolinao

VODIPO = 46

DIP = +10

VGDIPG = 1

VGDIPG = 0

DIP=-27

DIP1B = 0.4

VXDIPX = 20

DIP2 = 0.1µM

VR DIPR= 2

VXDIPX = 26

VQDIPQ = 88

Nearshore

VODIPO = 35

VGDIPG = 2

DIP = -97

DIP1N = 0.4µM


C n p fluxes in the coastal zone

LINGAYEN GULF

DIN Budget (fluxes in 106 moles/yr)

DIN3 = 0.5µM

VRDINR = 7

Ocean

VXDINX = 282

VQDINQ = 8

VODINO = 262

VQDINQ = 4

DIN = -310

Upper Gulf

VRDINR = 2

VODINO = 350

DIN = -180

Bolinao

VGDING = 28

VGDING = 39

DIN1B = 3.9µM

VXDINX = 211

DIN2 = 0.8µM

VR DINR= 10

VXDINX = 78

VODINO = 262

VQDINQ =128

DIN = -313

Nearshore

VGDING =11

DIN1N = 1.7µM


C n p fluxes in the coastal zone

Stoichiometric Links

Net ecosystem metabolism (p-r) or photosynthesis minus

respiration, can be calculated using the formulation

(p-r ) = -DIP  (C:P)part

Estimates of (nfix-denit) or N-fixation minus denitrification,

can be approximated using the formulation

(nfix-denit) = DIN - DIP  (N:P)part

where (C:P)part and (N:P)part are the ratios of organic matter reacting in the system


C n p fluxes in the coastal zone

+5.9

Table 2. Summary of nonconservative fluxes in three

boxes of Lingayen Gulf.


C n p fluxes in the coastal zone

Table 3. Effects of changing waste load on

(p-r) and (nfix-denit).


C n p fluxes in the coastal zone

IMPLICATIONS

The system is able to breakdown waste inputs and export most of these as N and P out of the

Gulf with some amount retained, perhaps in the

sediments.

 Since the average nutrient concentrations of N and P in the upper Gulf have not varied much over the years, this is an indication of the system’s current assimilative capacity.

However, buildup of organic matter is critical

for the nearshore and Bolinao boxes and will

eventually affect the Gulf’s ability to process these

materials.


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