An analysis of conventional on-farm development projects pointed out the lack of a systematic procedure applicable to implementation of the works. A new procedure has been developed by clarifying the requirements of each stage of the work from the field investigation to the construction and supervision stage. This procedure was characterized by: (1) adopting a grid survey map, (2) specifying the disposal of the soils, (3) estimating the earthmoving volume with the ponderable balancing method, (4) establishing criteria for quality control and (5) determining the scope of work of the supervisor.
For examining adaptability, the procedure was applied to an on-farm devel opment project in Tanzania, which had the purpose of constructing 3, 800 paddy fields with a dimension of 100×30m.
On the basis of this application it was concluded that:
(1) a grid survey map was sufficient for designing on-farm works;
(2) rational disposal of the soil had a good effect on the growth of paddy;
(3) efficient design and the ponderable balancing method could exactly cal culate the earth works;
(4) established criteria for quality control were justified by the smooth exe cution of the works and the easy farm operation; and
(5) the supervisor with conferred power could control the progress and the cost of the words.

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A series of analyses on the rainfall-runoff relationship was performed for the catchment area of Muda and Pedu Reservoirs (1, 155.1km²), which is covered by primeval tropical forests. In a normal year, the actual annual runoff from the catchment was about 640mm in depth as compared with the annual mean rainfall of 2, 250mm. Runoff percentage in the catchment ranged between 20 and 37% with an average of 28%. Rainfall loss ranged from 1, 300 to 1, 900mm/y or from 3.6 to 5.2mm/d. In the time series analysis of the rainfall-runoff relationship, four multiple regression equations for the specified periods of one month, 10-day, 5-day and 1-day were derived. These equations appear to be applicable to the setting of the schedule of water release from the reservoirs.

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This series of studies is intended to provide better under standing of water erosion and its simple control practices in reclaimed sloping land. The sloping land with 8% steepness on the Sera Plateau in the central part of Hiroshima was chosen as the study area.
Three varieties of straw matting mulch were studied to determine their effects on quantity of soil loss. They included 40, 60, and 80% straw mulch covering the bare soil surface. Soil losses from the plots were measured by using the spot level and bucket techniques, and the comparison between these two techniques is also discussed. Moreover, the USLE-predicted soil loss was presented for comparison with the soil loss data derived from direct measure ment under bare and mulched conditions.

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A demonstration and training program in traditional Japa nese deep well drilling for water known us, Kazusa-Bori in the Province of Batangas, Philippines, were conducted by the RCA Kazusa-Bori team, composed of two experts and one coordinator, from February 17 to April 3, 1987. This paper describes the mechanism and procedure of Kazusa-bori, gives the results of a questionnaire given to participants at the end of their training period, and estimates the cost of Kazusa-Bori in several developing countries
Kazusa-Bori requires the use of indigenous materials, such as bamboo trees, log poles, iron pipes, ropes, etc., which are readily available and obtainable in most developing countries. In addition, manpower is used as the power source. This method, therefore, has been suggested for developing water resources for both irrigation and human consumption in various countries. This paper reveals that Kazusa-Bori has a high degree of adaptability as well as limitations, when being introduced abroad.

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Drip irrigation is a promising technology for helping to solve shortages of water and food in developing countries.
The economy of Senegal is highly dependent on agriculture, which is vulnerable to climate. Climatic fluctuations compounded by the effects of desertification affect agricultural production, causing reductions in food supplies which in turn have an effect on national food security. Drip irrigation should be used more often as a means to control or eradicate these problems of drought/desertification and thus to increase and stabilize agriculture.
Today, newly improved drip equipment to apply water more efficiently and better filtration techniques to correct emitter clogging make this system work better than conventional means of water application. Drip irrigation could therefore be the solution to the challenge set by the government of Senegal to solve the problem of food shortage and desertification.

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This study is a technical study on land use planning in an urbaizing village. Ianalyzed farmers' behavior regarding agricultural land use and tried to study “agricultural side -farmers' logic” for land use planning. In three towns in Kyoto Prefecture, I investigated farmers' thinking regarding agricultural land use using the replies to a questionnaire for local farmers (3, 293) and non-local farmers (1, 294). I analyzed the data collected by a pubblic institution on agricultural land use, and tried to interview someone regarding the use of each lot. In addition, Iinvestigated the same problem in Saitama Prefecture.
The principal topics investigated are: 1. Areal characteristics of farmers' agri cultural land use; 2. Positional characteristics of farmers' agricultural land use; and 3. Transition of agricultural land ownership and use, by the purchase of substitute land.

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