| dc.description.abstract | Land use which is not compatible with land capability and lack of awareness to apply soil conservation measures, are the causes of increasing erosion and decreasing soil productivity which ultimately lead to low income of the farmers. Therefore, there is a necessity for proper land use management plan, particularly in the Lahumbuti catchment for achieving sustainable agricultural development.
The research that has been conducted in Lahumbuti catchment. has the objectives of evaluating land use and land capability, and also le::rrning the agrotechnolo-g-; applied in the Lahumbuti catchment. Beside that, the study was also aimed at designing alternative for land use management plan which is compatible with land capability to achieve sustainable watershed management at Lahumbuti catchment.
Method used in this research was survey method that comprised collection of primary data and secondary data. Primary data includes (a) physical condition of the land (steep slope and length of slope, permeability, effective soil depth, drainage, texture, stucture and content of the soil organic matter) and (b) socio-economic condition (demography, production facility, cost, farmers income and agrotechnology applied in the study site), evaluation of suitability betwen land use and land capability using Klingebiel and Montgomery criteria, erosion estimate using USLE method, calculation of Etol using Hammer method (1981 and evaluation of living standard appropriateness using Sajogyo and P. Sajogyo ( 1990 ). Secondary data are in the form of daily rainfall data, facts in the district, topographic map and soil map.
Research result showed that generally land use in Lahumbuti catchment are accordance with their land capability, although there were several farming activities that were conducted on steep slope. Planting pattern and agrotechnology adopted by farmer were still traditional. Result of erosion prediction at intensive obsevation site indicates that the occuring erosion (13,03-262,10 tonnes/ha/year) were greater than the soil loss tolerable (8,65-48,% tonnes/ha/year), resulting in decline of land productivity and farmers low income (Rp. 2.822.650,- - Rp. 8.033.100,- HH/ha/year). Therefore, there is need for change in cropping pattern and agrotechnology, accompanied with soil conservation measures so that erosion could be reduced to a minimum level which is smaller than the tolerable level.
Pursuant to equality of land capability class and types of cultivated crop betwen the intensive observation sites and the land units at the whole of Lahumbuti catchment, land use recomendation in the catchment is that at land class I (21.870 ha) and land class II (1213,5 ha) the suitable land used are mixed garden and dry land, there would be inter cropping (tumpangsari, tampang si1>ip) and multiple cropping, accompanied by mulch and construction of bund terrace. Forest and shrubland could be converted to mixed garden and dry land or agroforestry system. Land class III (11.624,1 ha) and class IV(28.373,7 ha) are | id |
