International Journal of Aquaculture, 2013, Vol.3, No.14, 73
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78
http://ija.sophiapublisher.com
74
catch produce per
Silvofishery
ratio.
1
Result and Discussion
1.1
Overview
Sinjaiis one of the coastal districts in South Sulawesi
province, situated in the eastern part of South
Sulawesi and borders Bone to the north, BoneBay
waters to the east, South Bulukumba district to the
south, and Gowadistrict to the west. Sinjai district has
nine small islands called Nine Islands, and has a
coastline spanning 31 km, 17 km of which lies along
secondary the the main land and another 14 km
surrounds the islands (Biro Pusat Statistik, 2010).
Along the coastline there is a potential of mangrove
ecosystems with total area of 1 351.50 ha. spreads
across three coastal sub-districts with sizes as follows:
(1)
NorthSinjai sub-district covering 254.10 ha or
18.84%, (2)
EastSinjai sub-district covering 947.50 or
70.02%,
and (3) Tellulimpoe sub-district covering an
area of 150.50 ha or 21.14% (Dinas Kelautan dan
Perikanan Kabupaten Sinjai, 2010).
In addition to mang roveeco systems, along the coast
of Sinjai district there is a potential of aquaculture
area of 1 033 ha, yet until 2011 only 716.50 ha of this
area had been optimally utilized. This pond area is
managed by different levels of technology packagesas
follows: traditional plus 90%, 7.5% semi-intensive
and intensive 2.5% respectively. The average of pond
produce for shrimp is 241 kg·ha
-1
·
yr
-1
and for milk
fish 670 kg·ha
-1
·
yr
-1
(
Dinas Perkeunan dan Kehutanan
Kabupaten Sinjai, 2011). The comparison between the
size of mangroves and pond sin Sinjai district is
65.35%
and 34.65%.
The results of several previous studies e.g. (Kathiresan
and Bingham, 2001) reveal that the conversion of
mangrove ecosystem into ponds should not exceed
70%
because failing to do so would disrupt the
ecological functions of mangrove ecosystems as
nutrient providers.
1.2
Aquaculture Produce and Benefit Value
Aquaculture system applied to the
Silvofishery
pond is
poly culture of shrimp, with milkfish as the primary
produce. Seaweed is not cultivated by reason of
limited sunlight. The surrounding ponds, however,
cultivate shrimp, milkfish and seaweedas their
primary cultivation. This poly culture approach is
consecondary red to have ecological, economic, and
social benefits.
Poly culture system or diversified cultivation in
Silvofishery
ponds ecologically aims to increase
nitrogen, phosphorus, and calcium through
decomposition processes. All nutrients can be utilized
by various cultured biota, so the potential for
deteriorating soil and water quality can be minimized.
Poly culture of shrimp, milkfish and seaweed formsa
mutually beneficial symbiosis.
The poly culture of shrimp, milk fishand seaweed in
ponds economically aims to make efficiency in all
utilization of land resources use, operating costs, labor
and so on. Poly culture system is said to be able to
maintain the efficiency of land because it can preserve
some types of organisms on the soil at the same time,
minimizing costinputs such as fertilizer, drugs and
laborissues.
In addition, the adoption of poly culture systemin
Silvofishery
pond is aimed at maintaining biodiversity;
the higher the biodiversity of an ecosystem, the higher
the ecological, economic and social functions. Further,
poly culture systems may involve some seasonal
workers at harvest time, as energy harvesters,
transporters, andsellers. That means the more various
commodity types in a particular pond, the more labors
are needed to deliver them to end customers.
Be secondary sprimary cultivated organisms such as
shrimp, milkfish, and seaweed, there are other
secondary organisms of various types of wild fish,
wild shrimp, and so forth which are also of high
economic value. The analysis results of
Silvofishery
pond total produce maintenance cycle
-1
reveals that
secondary aquaculture produce helps primary
aquaculture produce, in addition to direct benefit of
mangrove ecosystem (Asbar, 2007).
1.2.1
Primary Aquaculture
The analysis of primary aquaculture produce results in
the following average scores: (1) shrimp by 241 kg·ha
-1
·
yr
-1
,
and (2) milkfish by 670 kg·ha
-1
·
yr
-1
.
Silvofishery
pond
produce in Sinjai, when compared to
Silvofishery
pond producein Tangerang, is relatively similar with
shrimp weighted to 200 kg·ha
-1
·
yr
-1
and milkfish of
700
kg·ha
-1
·
yr
-1
(
Soewardi, 2011). The primary
aquaculture produce perpond ratio is presented in
Table 1.