2 Synergy of GIS and MCDA is used to dealing with spatial planning. And the
process can mean that the transformation process on the map that will be assessed and combined with the assessment of the decision maker to produce accurate
information Malczewski, 2006. The implements of GIS-MCDA also used the assessment of a specialist reference group expert that has been identified as a
basic reference. The GIS-MCDA system could solve the potential problem with the approach of communication in building communication with stakeholders. In
addition, tools to the implementation to solve an occurring issue are also used. The overall system that will be developed assembles information on the
importance of many variables of coastal marine. Other advantages used MCDA as management data so that it could expect output information, and update easily.
This information is useful for the local community who lives in and around the coastal area to be involved in coastal development and conservation and to
understand the environmental problems of coastal marine. Thus, special problems could be identified, compared with coastal marine globally to show which coastal
areas may share common problems and the possibility to cooperate in solving those problems.
Saleh gulf, as one of the coastal area in Sumbawa Island, has also a threat such as exploitation that can lead to environmental and natural resources degradation of
the coastal area if not managed properly. The coastal zone has a coastline length of 79.6 kilometers, and the total area is about 20 153.15 km
2
. The facts in Sumbawa coastal region appeal to development of various activities.
1.2 Research Objective
The objective of this research is to analyze the marine suitability for coastal area using multi-aspect technique for the purpose of decision making using minimum
threshold criteria, simple additive weighting, and fuzzy logic for marine coastal suitability
3
1.3 Scope of Research
• Study area will be chosen in Saleh gulf in Sumbawa Island. • The potential cultivation zone is determined for analysis seaweed and pearl
oyster cultivation. The methods applied in this research are minimum threshold criteria, simple additive weighting SAW and fuzzy method for
marine coastal suitability.
4
II. LITERATURE REVIEW
2.1 Definition and Characteristic
Coastal waters of coastal biological resources coastal waters are potential enough to be developed. This research emphasized on marine coastal suitability analysis
for coastal aquatic seaweed and pearl oyster cultivation. Common products of the coastal marine are much as food or as an additive for the food industry,
pharmaceuticals, cosmetics, and others. In addition, it could be also utilized as green marine as well as cattle and fish feed components.
Table 2-1. Marine coastal suitability for seaweed cultivation source: Suryanto et. all, 2006
Parameter S1 [80]
S2 [60]
S3 [40]
N [1]
Open water depth m [35]
1 - 5 1
5 Dissolved oxygen mgl
[10] 6
5 – 6 4 – 5
4 Salinity ppt
[10] 28 - 36
20 – 28 12 – 20
12 36
Temperature
o
C [10]
26 - 31 24 - 26
31 – 33 20 - 24
33 – 35 20
35 Brightness
[25] 75
50 – 75 25 – 50
25 pH
[10] 7.5 – 8.3
7 – 7.5 8.3 – 8.5
6.5 - 7 8.5 – 9
6.5 9
Table 2-1 and table 2-2 are matrices based on the study of library and information specialists who are experts in the field Wiradisastra, 2004. Individual fitness
levels are divided into four classes, namely classes S1, S2, S3, and N. • S1 class most suitable is a region that does not have any constraint for a
particular sustainable use; • S2 class suitable is a region that has little restraint for a particular use. This
constraint will affect productivity and profits earned from the marine coastal; • S3 class less suitable is a region with a constraint which has a higher weight,
but can still be improved by using high technology treatment.
5 • N class not suitable is a region with very heavy constraint so it will be not
possible to be used a particular sustainably. Therefore the classification will be built based on criteria and data shown in table
2-1 and table 2-2. Table 2-2. Marine coastal suitability for pearl oyster cultivation source:
Suryanto et. all, 2006
Parameter S1 [80]
S2 [60]
S3 [40]
N [1]
Open water depth m [50]
1 - 11 11 – 28
28 – 36 16 – 20
1 36
Dissolved oxygen mgl [10]
6 5 – 6
4 – 5 4
Salinity ppt [10]
27 – 34 24 – 27
34 – 38 20 – 24
38 – 40 20
40 Temperature
o
C [10]
26 – 29 23 - 26
29 - 31 20 - 23
31 – 34 34
20 Brightness
[10] 80
70 – 80 60 – 70
60 pH
[10] 7.7 – 8.3
7.7 – 7.7 8.3 – 8.5
7 - 7.5 8.5 – 9
9 7
2.1.1. Characteristic of Coastal Marine
The characteristics of the location to be studied can be expressed into several parameters. Each commodity has a value and certain bio-physical measurement
requirements that should be fulfilled for a particular commodity.
2.1.1.1 Brightness
Brightness shows level of the depth of sunlight penetration to sea surface. Brightness in coastal area is strongly influenced by turbidity and sediment. If the
turbidity is high then the sunlight penetration to the water is low therefore lower level of brightness. Sunlight radiation is needed for photosynthesis process of
plant, if the turbidity of sea water is high, then the sunlight radiation will be less than the sea water with less turbidity. Brightness ranges highest from 75 for
seaweed and 80 for pearl oyster, where the diversity of the brightness value is caused by water depth contour at the location of the survey Suryanto, et. all,
2006. At some points of research which have a shallow depth, measurement of
6 the brightness can reach the bottom water, which indicates that the water
condition is very good to be used for the development of marine cultivation. Production of seaweed and pearl oyster increases in the dry season, and will
become less in rainy season.
2.1.1.2 Dissolved Oxygen
Dissolved oxygen DO is derived from the results of a photosynthesis process of water plant or diffusion of oxygen into water by aeration rapid movement as a
waste product of photosynthesis. Photosynthesis processes could occur in green plants and some chlorophyll-containing bacteria Utama, 2005. Oxygen is needed
by all sentient life in the water such as fish, shrimp, shellfish and other animals, including microorganisms such as bacteria. DO is the most important indicator of
the health of a water body and its capacity to support a balanced aquatic ecosystem of plants and animals. Waste water containing organic oxygen
consuming pollutants depletes the dissolved oxygen and may lead to the death of marine organisms. DO content in water provides a high level guidance to the
primary productivity of water. Oxygen molecules are contained in the physics of soluble water. Hence, solubility is strongly influenced by water temperature. DO
from the field measurements indicated highest from 2.6 - 4.7 mg I for seaweed and pearl oyster. In overall the observed water is suitable enough to support
aquatic life organisms Wiradisastra, 2004.
2.1.1.3 Temperature
The sea temperature is influenced by sunlight radiation to the earth. Sunlight heating the surface sea water in tropical regions will be different with the results
of the heating in the middle latitude regions, or poles. In the tropics the sun fell down almost perpendicular, whereas in the polar region generally receive sunlight
with a skew. Temperature decreases regularly according to the depth, more depth from surface the temperature will be lower. This is due to lack of intensity of the
sun into the waters. However, although in the tropics more heat from the poles, the tropics have a temperature lower than the temperature of sea water in the
7 subtropical regions Utama, 2005. This is because much cloudy cover in many
tropical areas compared with sub tropic. Temperature changes slowly from the coast towards offshore, temperature generally is higher in coastal areas because
the sea could absorb sunlight easier while for the sea it is not easy to change the temperature when the environmental temperature does not change, commonly the
temperature of the offshore is stable. Temperature is one of the most important factor for living organisms in the ocean, because temperature affects both
metabolism and proliferation activity of any organism. Average temperature between each measurement point does not differ significantly, which range from
21
o
C – 32
o
C for seaweed and 21
o
C – 32
o
C for pearl oyster, where the temperature was within the category is suitable for developing marine farming area. The range
of temperature is not large due to Indonesian waters have a uniform temperature pattern Wiradisastra, 2004.
2.1.1.4 Acidity
Acidity or Potential of Hydrogen pH measured concentration hydrogen ion in water, indicated the acid and alkalie degree of sea water. Generally, acidity scale
is from 0 to 14, the mean value is a neutral number 7. Measurement of acidity is very important because acidity values affect the solubility and availability of
various nutrition for the organism. Sea water has ability to sustain fluctuating changes in acidity. pH or water acidity is one of the factors affecting productivity.
pH is measured during the study which ranged from 7.2 - 7.9 ppm for seaweed and 7.2 – 7.9 ppm for pearl oyster. The pH ranges show that the open water is
productive. Changes in pH can have bad consequences for the life of sea biota, either directly or indirectly Wiradisastra, 2004.
2.1.1.5 Salinity
Salinity is the concentration of soluble ions mineral in water and expressed in mg per liter ppm, or the amount of salt in grams per kilogram of sea water. Sea
water generally contains 3.5 salt, dissolvable gases, organic materials and some particles of insoluble substances. Salinity is also influenced by the osmotic
8 pressure; the more the higher salinity the more higher the osmotic pressure,
another cases influence by tidal and seasonal. Salinity around the estuary tends to decrease, but during the dry season when the flow of the river water decrease, sea
water flow further to around estuary so that the increased salinity in estuary. In contraraly in the wet season, there is an increase flow freshwater from rivers
which empty into the sea, so salinity in the estuary decrease. Salinity is very influential on the cultivation of seaweed and other organisms, because each
organism has a certain range for life. Salinity measured during the study ranged from 33 - 34 ppt for seaweed and 33 – 34 ppt for pearl oyster. Many
environmental factors affected the changes in the salinity such as: water circulation, evaporation, precipitation and flow of the river to the estuary
Wiradisastra, 2004.
2.1.1.6 Depth of Sea Water
Depth of sea water is one of the most important parameter in studying the dynamics of the sea. Slight differences in the depth for example due to
differences in surface heating will result to differences in ocean currents. Therefore, the determination of depth is important in oceanography. Water
pressure increases according to the depth of the sea. Depth of sea water is usually measured by using the echo sounder or CTD conductivity, temperature, depth.
The depth is measured using CTD based on the value of pressure. Depth Measurements are made at selected points to represent the whole mapped area.
The information about the components of this data is obtained from field, the lowest is about 1.4 meter and the highest depth is 85 meter. Reference data which
have been collected and processed from various maps are then overlaid and spatial interpolation technique Wiradisastra, 2004.
2.2 Interpolation of Surface Analysis
The surface function representation of digital map is fundamental to almost all analysis of spatial data in GIS. There is a surprising variety of algorithms for even
the fundamental operation of deriving a map of aspect and slope. In this research
9 use creating surface or called interpolators, create a continuous surface from
sample input point values, and using spline method as interpolators to build a location for placing result of overlay. Spline method is general purpose
interpolation that fits in a minimum curvature surface through the input points. This method is best use for gently varying surface such as elevation.
Interpolation is used to estimate the value of a function between known data points without knowing the actual function. Interpolation methods can be divided
into two main categories: • Global interpolation. These methods rely on a constructing single equation
that fits all the data points. This equation is usually a high degree polynomial equation. Although these methods result in smooth curves, they are usually
not well suited for engineering applications, as they are prone to severe oscillation and overshoot at intermediate points.
• Piecewise interpolation. These methods rely on constructing a polynomial of low degree between each pair of known data points. If a first degree
polynomial is used, it is called linear interpolation. For second and third degree polynomials, it is called quadratic and cubic splines respectively. The
higher the degree of the spline, the smoother the curve. Splines of degree m, will have continuous derivatives up to degree m-1 at the data points.
Kruger, 2008
2.3 Minimum Threshold Criteria for Marine Coastal Suitability
