[1]	For more details, consult T. Takahashi (March, 2000), Deficiency of sulfur and some micronutrients in Zambia (in Japanese), Expert Bulletin, Vol. 20, No. 6, pp. 19-44, AICAF.
[2]	For details, consult T. Takahashi (July, 2001), Sodic paddy soils on the southern mountain foot of Kilimanjaro: Influence of carbonatite densely distributed around the Great Rift Valley in East Africa (in Japanese), Expert Bulletin, Vol. 22, No. 2, pp. 1-29, AICAF.
[3]	Obtained by SAR=Na/((Ca+Mg)/2)^1/2. To put it very simply, SAR may be referred to as thermodynamically converted sodium concentration.
[4]	At the study area in Malawi, the weeding time for paddy rice overlaps that for maize during the rainy season.
[5]	Applicable to Cote d'Ivoire and Tanzania. In Cote d'Ivoire, 300,000 tons of polished rice was imported in 1990 and the domestic demand for rice is high. On the other hand, a considerable portion of rice produced at the study area in Tanzania is distributed as black market rice to Kenya, a neighboring country with high demand for rice.
[6]	T. Wakatsuki (2001), Lowland soils in tropical Africa (in Japanese), K. Kyuma (Eds.), Tropical pedology, pp. 180-196, Nagoya University Press.
[7]	In the KADP area, since the standard size of paddy field is 0.3ha, a common agricultural extension manual has been made for a 0.3ha field regarding nursery bed area, quantity of seedlings to be planted, standard amount of fertilizer to be applied, etc. However, the existing paddy fields in other areas are smaller in scale and the area per field is different, and thus the common manual cannot be applied directly without modifications. Further, for this area is in a predominantly maize zone, there is shortage of extension workers familiar with rice farming.
[8]	It was found that in Malawi night watch to prevent hippos' intrusion into farmland and increase in diseases due to lack of safe drinking water influenced the number of farming hours secured.
[9]	It was revealed that in Zambia farmers usually could not afford more than two kinds of chemical fertilizer because fertilizers were expensive and compounding was time-consuming. Prompted by the finding, Mitsubishi Corporation and Dia Chemical Co., Ltd. embarked on developing chemical fertilizers containing sulfur and minor elements after the completion of the present study.
[10]	In Tanzania, paddy fields developed in the Lower Moshi area of Kilimanjaro region with financial assistance from Japan have very high soil fertility and yield over 6.5 ton/ha with nitrogen fertilizer only.
[11]	In the colonial period, former suzerains selectively developed fertile land, and many plantations still remain in such areas today. Much of the farmland left to ordinary farmers is low in fertility. In Zambia, there is a sharp contrast between plantations concentrated in the central belt zone (with soils of high fertility) and farmland cultivated by small farmers in the north and the west (with soils of low fertility).
[12]	For example, the Netherlands has decided as its basic development assistance policy toward Africa not to offer agricultural assistance for areas of low agricultural potentials but instead support vocational (technical) training as a measure of livelihood improvement.
[13]	This ideology is presented in Maintaining and increasing production by soil improvement and fertilizer application by A. Tanaka (1997) and Introduction to tropical agriculture (pp. 493-516; pub. Tsukiji-shokan).
[14]	Tephrosia vogelli observed in Malawi contains an insecticidal property (tephrosin) accumulated in its flowers.
[15]	The members of a farmers women's group, who observed with the farmers of the study area during the study in Malawi, emphasized as a merit of cooperative operation that it served as mental support, making them feel that they would be able to get through any hard work (by working together).