128
A. D. BONEY
area of 30 000 acres (Thompson, 1952 ; Womersley, 1952, 1969 ; Cribb,
1954). Ecklonia radiata is of potential economic value on the eastern
coast of Australia, together with the red alga Gracilaria verrucosa
(Wood, 1952). I n New Zealand the standing crop of Macrocystis in the
Cook and Foveaux Straits has been estimated at 78 000 tons fresh weight
(Chapman, 1952). Thivy (1952) states the Australian standing crop of
&milaria verrucosa to equal 62 500 tons fresh weight.
6. India
Qelidium micropterum appears to be the seaweed of most importance,
and in the Mandaparam-Kilakarai region occurs in quantities of about
3 lb fresh weight per m2 of reef. The total “ agarophyte ” standing
crop is estimated at 3000 tons on Indian shores. Sargmsum and
Turbinaria are the more important brown algae (Thivy, 1952). The
same author estimates that the total agarophyte standing crop for
Korea stood at 1103 tons fresh weight, and for Japan 700000 tons.
Whilst the standing crops are not known for all parts of the world
where there are harvestable seaweeds, there is now much information
on the types of marine algae which may be exploited. The relevant
data are summarized in Table VIII, together with the authorities for
the information. This Table gives some indication of the extent to
which the potentialities and use of economic seaweeds is now being
studied.
C. Summary of data concernilzg the quantities of harvested seaweed
Whilst estimates of standing crops are essential for knowledge of
the exploitable seaweed beds, useful information can also be obtained
from data on the ,quantities of seaweed harvested in previous years.
Results of this nature may be biased by the requirements of a, particular
industry, but long-term records may indicate the possible effects of
regular cropping on the harvestable material.
The Danish use of PurceUaria fmtigiata forma aegagrophila may be
taken as an illustration. Over a 16 yr period some 112 900 tons of fresh
weed have been harvested (Sund and Bjerre-Petersen, 1952, 1964),
from which 4 926 tons of extractive have been obtained. A graphical
summary of the quantities of seaweed collected over the years is shown
in Fig. 2, and shows the marked acceleration in the amounts harvested
over recent years. I n common with the increased quantities harvested,’
a more efficient utilization has also been observed ; an agar production
of 2.5y0 per weight of raw weed in the early years has been increased
to 4%. The quantities collected reflect the increased demand for the
A. D. BONEY
area of 30 000 acres (Thompson, 1952 ; Womersley, 1952, 1969 ; Cribb,
1954). Ecklonia radiata is of potential economic value on the eastern
coast of Australia, together with the red alga Gracilaria verrucosa
(Wood, 1952). I n New Zealand the standing crop of Macrocystis in the
Cook and Foveaux Straits has been estimated at 78 000 tons fresh weight
(Chapman, 1952). Thivy (1952) states the Australian standing crop of
&milaria verrucosa to equal 62 500 tons fresh weight.
6. India
Qelidium micropterum appears to be the seaweed of most importance,
and in the Mandaparam-Kilakarai region occurs in quantities of about
3 lb fresh weight per m2 of reef. The total “ agarophyte ” standing
crop is estimated at 3000 tons on Indian shores. Sargmsum and
Turbinaria are the more important brown algae (Thivy, 1952). The
same author estimates that the total agarophyte standing crop for
Korea stood at 1103 tons fresh weight, and for Japan 700000 tons.
Whilst the standing crops are not known for all parts of the world
where there are harvestable seaweeds, there is now much information
on the types of marine algae which may be exploited. The relevant
data are summarized in Table VIII, together with the authorities for
the information. This Table gives some indication of the extent to
which the potentialities and use of economic seaweeds is now being
studied.
C. Summary of data concernilzg the quantities of harvested seaweed
Whilst estimates of standing crops are essential for knowledge of
the exploitable seaweed beds, useful information can also be obtained
from data on the ,quantities of seaweed harvested in previous years.
Results of this nature may be biased by the requirements of a, particular
industry, but long-term records may indicate the possible effects of
regular cropping on the harvestable material.
The Danish use of PurceUaria fmtigiata forma aegagrophila may be
taken as an illustration. Over a 16 yr period some 112 900 tons of fresh
weed have been harvested (Sund and Bjerre-Petersen, 1952, 1964),
from which 4 926 tons of extractive have been obtained. A graphical
summary of the quantities of seaweed collected over the years is shown
in Fig. 2, and shows the marked acceleration in the amounts harvested
over recent years. I n common with the increased quantities harvested,’
a more efficient utilization has also been observed ; an agar production
of 2.5y0 per weight of raw weed in the early years has been increased
to 4%. The quantities collected reflect the increased demand for the