Ecology Series 3 WITH AUDIO

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Robert Perry Malibu High

P r esen t s

cology basics

Series Three The 10% Rule and Biomagnification

A food chain

SHOWING THE FLOW OF ENERGY AND MATERIALS.

The maximum amount of ENERGY that passes from one trophic level to the next is 10%.

90% of the ENERGY at each trophic level is used to keep the organisms alive and is converted to HEAT.

2nd Law of Thermodynamics Energy tends to spontaneously degrade from a concentrated form to a dispersed form.

Or‌.

Organisms in each trophic level use up most of their energy keeping themselves alive.

90% of the ENERGY captured

by PRODUCERS is used to keep themselves alive (converted to heat).

T

N

HE A

O T Y H P

PL

O T K N A

The 10% RULE !

Max. 10 % to HERBIVORES

3rd Order Producers are the BASE CARNIVORES of the pyramid of biomass because their ENERGY comes direct 2nd Order CARNIVORES from the SUN. SUN

1st Order CARNIVORES

HERBIVORES

PRODUCERS

Max. 10 % to CARNIVORES

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HE A

O

%

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A L P

N O T K N

90

%

N

10

O T Y H P

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O T K N A

The 10% RULE !

90% was used to keep the HERBIVORES alive.

3rd Order CARNIVORES

HERBIVORES exist on only 10% 2nd Order of the ENERGY CARNIVORES from PRODUCERS. 1st Order CARNIVORES

HERBIVORES

PRODUCERS

O V I N R A C r e d r

Max. 10 % to 2nd O. CARNIVORES

T

HE A

90 %

%

O t 1s

10

O

ES R

10

ZO

A L P

N O T K N

%

%

N

10

O T Y H P

PL

O T K N A

The 10% RULE !

1st O. Carnivores are max.10% 3rd Order of HERBIVORES. CARNIVORES 2nd Order CARNIVORES

1st Order CARNIVORES

HERBIVORES

PRODUCERS

O V I N R A C r e d r

ES R

%

O t 1s

10

O

%

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A L P

N O T K N

10

%

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O T Y H P

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The 10% RULE !

2nd Order CARNIVORES

There isn’t much 3rd Order ENERGY CARNIVORES left near the top !

2nd Order CARNIVORES

1st Order CARNIVORES

HERBIVORES

PRODUCERS

The 10% rule...

3rd Order CARNIVORES

2nd Order CARNIVORES

...results in this ECOLOGICAL PYRAMID

1st Order CARNIVORES

HERBIVORES

PRODUCERS

The 10% rule...

1

10

100

1,000

10,000

...is used to help predict NUMBERS of organism

The 10% rule...

...is used to help predict BIOMASS.

1 TON

10 TONS

100

TONS

1,000

TONS

10,000

TONS

90% used to keep organisms alive (=heat)

S E R

d r 3

O V I N R A .C 10% O

d n 2

S E R

O V I N R A .C 10% O

Only 10% can be passed to next level

r e rd O t 1s

S E R O V I N R CA

10% B R HE

O V I

S E R S R E C DU

10% O R P

Biomagnification

Biomagnification "Biomagnification is the sequence of processes in an ecosystem by which higher concentrations of a particular chemical, such as the pesticide DDT, are reached in organisms higher up the food chain, generally through a series of prey-predator relationships."

- Oxford University, 2008 Biomagnification – “Result of the process of bioaccumulation and biotransfer by which tissue concentrations of chemicals in organisms at one trophic level exceed tissue concentrations in organisms at the next lower trophic level in a food chain.” Environmental Protection Agency, 2010 Biomagnification – “Biomagnification is the process whereby the tissue concentrations of a contaminant increase as it passes up the food chain through two or more trophic levels.” - Nowell, Capel, and Dileanis; 1999

Biomagnification Biomagnification – “Biomagnification begins with ingestion by a predator of a lower trophic level organism whose tissues contain contaminant residues….The available evidence suggests that biomagnification may occur under conditions of low water concentration for compounds of high lipophilicity, high persistence, and low water solubility (Biddinger and Gloss, 1984).” - Nowell, Capel, and Dileanis; 1999 Biomagnification – “Bioaccumulation of a pesticide through an ecological food chain by transfer of residues from the diet into body tissues. The tissue concentration increases at each trophic level in the food web when there is efficient uptake and slow elimination (Rand and Petrocelli, 1983).” - International Union of Pure and Applied Chemistry, 1996m

BIOMAGNIFICATION

PREDATORS AT THE TOP OF THE FOOD CHAIN CONTAIN THE MOST POLLUTION DUE TO BIOMAGNIFICATION.

BIOMAGNIFICATION

OF CONTAMINANTS (numbers are approximate)

10,000x

1,000x

100x

10x

1x

CASE STUDY: MONTROSE CHEMICAL CORP. TORRANCE, CALIFORNIA

Palos Verdes

MONTROSE CHEMICAL CORP From 1947 to 1983, Montrose Chemical Corporation manufactured DDT at its plant near Torrance, California.

The plant discharged wastewater containing the nowbanned pesticide into Los Angeles sewers that emptied into the Pacific Ocean off White Point on the Palos Verdes Shelf (PVS). The DDT manufacturing process also resulted in groundwater and surface soil contamination on and near the Montrose plant property.

It is estimated that over 800 to 1000 tons of DDT were discharged between the late 1950s and the early 1970s.

Several other industries also discharged PCBs into the Los Angeles sewer system that ended up on the PVS by way of outfall pipes. The PVS site is defined by the large area of DDT- and PCB-contaminated sediment on the ocean floor in the vicinity of the Palos Verdes peninsula, near Los Angeles, California.

LOS ANGELES COUNTY SEWER OUTFALL and Peak Total DDT in Sediments White’s Point, Palos Verdes

Brown Pelican nesting on Anacapa Island.

Brown Pelicans near extinction.

Brown Pelican population rebounds

After the ban DDT in the early 1970’s in the U.S., brown pelican populations started to recover almost immediately in the southeast as residues and eggshell thinning declined and productivity increased. The recovery in CA took longer because of the much greater DDE levels (Montrose Chemical).

IMAGE: © Dan Guravich/CORBIS

.....Pelicans incubate their eggs, keeping them warm and turning them over, by using their vascularized feet. A synthetic insecticide first discovered as such in 1939 — DDT was first synthesized in 1877 — DDE was in the Los Angeles area sewage system starting in the 1940's and washed into the marine environment. DDE is a metabolite of DDT and is a very stable compound that accumulated in the tissues of fishes and birds, moving up the food chain, especially affecting fish-eating birds such as the pelicans.

The effect was disastrous: by the late 60's eggshells were so thin that in 1970, only 1 chick hatched out of the breeding ground of approximately 5,000 nesting sites. If a shell is less than 20% of normal, the egg will not hatch. In Southern California, shells were 31-51% thinner; even some shell-less eggs were laid. For an analysis of eggshell thinning.

Similarly, for our national symbol, bald eagles, also fish eaters, the numbers dropped to less than 450 nesting pairs in the US, excluding Alaska. Also seriously affected were ospreys and peregrine falcons.

On December 19, 2000, the U.S. Department of Justice (representing the EPA and several natural resource trustee agencies) and the California Attorney General announced a $73 million settlement with Montrose Chemical Corporation of California, Aventis CropScience USA Inc., Chris-Craft Industries Inc., and Atkemix Thirty-Seven Inc., companies that either owned or operated DDT-manufacturing plants in Los Angeles County.

Along with the prior settlements in this case, a total of approximately $140 million was collected to be used by federal and state agencies to help rehabilitate natural resources and clean up DDT contamination on the offshore Palos Verdes Shelf. Department of Justice News Release