Phosphorous cycle in marine environment

1. Submitted by:
Kumar Kashyap
M. Tech Marine Biotechnology
Ist Sem
Introduction to Marine Sciences

2.  Phosphorus is essential for life processes in
plants and animals.
 Phosphorus is a part of the molecule that
carries energy in living cells = ATP

3.  Phosphorous also forms the phosphate-ester
backbone of DNA and RNA.
 Phosphorous is also an important consituent
in various cell components such as
phosphoproteins and phospho-lipids in cell
membrane.

4.  How do plants and animals use phosphorus?
Plants Animals (humans)
Developing healthy
seeds, root
growth, and stem
strength!
Developing healthy
bones (works with
Ca to build bone
tissue)
Corn with a
Phosphorus deficiency

5.  The presence of phosphorous in the
environment can impact primary production
in the oceans, species distribution and
ecosystem structure.
 In some marine and estuarine environment,
phosphorous acts as a limiting factor for the
primary production.
 So the availability of phosphorous in the
marine environment can strongly effect the
marine carbon cycle.

6.  A phosphorus cycle may also be referred to
as mineral cycle.
organismatmosphere

7.  The phosphorus cycle is the movement of
phosphorus from the environment to organisms
and then back to the environment.
 Phosphorus is mainly found in water, soil, and
rock.
 The phosphorus cycle is the SLOWEST cycle.

9.  Eleventh most abundant element in the
Earth’s crust, comprising approximately 0.1%
by mass.
 Occurs in both organic and inorganic forms.
The inorganic phosphate in minerals and
organic phosphate in rocks and soils.

11.  Phosphorous is primarily delivered to the ocean
via continental weathering in dissolved or
particulate phase via riverine flux.
 Much of the riverine particulate phosphorous is
retained within continental shelves and hence is
not involved in the open ocean processes.
 Atmospheric deposition through aerosols,
volcanic ash and mineral dust is also important
particularly to remote oceanic locations.
 The dissolved phosphate is converted to
particulate form and then.
 The dominant sink for oceanic P is deposition
and burial in marine sediment in this particulate
form.

12.  A minor sink is the uptake through sea water.
 In the open ocean the most of the
phosphorous remains in the dissolved form
(3*10^15) out of which maximum part is in
the deep ocean (2.9*10^15) and a small
portion (0.1*10^15) is in the surface waters.

13.  Phosphate containing fertilizers and
phosphorous from other human activities are
washed into rivers, groundwater and
estuaries and adds a substantial amount of
anthropogenic phosphorous to the oceans.

15. 1. Humans mine LARGE quantities of phosphate rock to
use in commercial fertilizers and detergents.
Phosphorous is NOT found as a gas, only as a solid in
the earth’s crust. It takes millions to hundreds of
millions of years to replenish.
2. Phosphorous is held in the tissue of the trees and
vegetation, not in the soil and as we deforest the
land, we remove the ability for phosphorous to
replenish globally in ecosystems.
3. Cultural eutrophication – ad excess phosphate to
aquatic ecosystems in runoff of animal wastes from
livestock feedlots, runoff of commercial phosphate
fertilizers from cropland, and discharge of
municipal sewage.

16.  Paytan, A. and Mclaiughlin, K. The oceanic
phosphorous cycle. Chemical reviews (2007),
Volume 107 (2), 563-576.