booklet aceh barat.pdf - Balai Penelitian Tanah

IV. APPROACH IN LAND EVALUATION
The process of land evaluation includes identification of land characteristics,
compilation of crop requirement information, matching of land characteristics with
crop requirements and screening of land suitability options to produce land use
recommendation (Ritung et al., 2007; Djaenudin et al., 2003). The requirements for
growth of various crops can be obtained from available literature such as Djaenudin
et al. (2003).
Matching (comparing) between land characteristics in every mapping unit
with crop requirements is normally conducted by computerized system e.g. using the
Automated Land Evaluation System, ALES (Rossiter and van Wambeke, 1997 and
1995) or manually if only a few points or mapping units are to be evaluated. By
computerized system the process can be executed very quickly for several crops
simultaneously.
The land suitability classifications are defined based on their most serious
limiting factors as shown in Table 7. Although only low soil pH that lead the suitability
falls into S3 while other land characteristics were within S1 and S2 classes, then the
suitability under the actual condition is S3. However, the pH problem is relatively
easily manageable and its category can shift to S2 or even S1 and thus the potential
suitability is S2. The recommendation as presented in this booklet is based on the
potential suitability.
Screening is necessary to match the suitable crops with the priority of
regional/district development and existing land use. In the screening for annual food
crops and vegetable crops, only S1 and S2 classes were considered, but for the
perennial tree crops, S3 or marginally suitable class was also included because of
the resilience and the importance of the perennial crop on the coastal area
protection.
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