Implication of Forage and Livestock Production on Soil Fertility in Nepal

The mid-hills of Nepal are characterised by complex and labour-intensive farming systems with low returns. About 70% of arable land in the hills can be classed as unirrigated hill slopes (bariland), and only about 30% is irrigated (khetland). Overall cropping intensities on bariland including kitchen gardening, are noted as being more than two to three times the quoted national average of 1.3 and 1.6 as reported by Hagen (1980, cited by Riley, 1991), and Panth and Gautam (1987, cited by Riley, 1991).

Increases in human population in the past twenty years have converted large parts of the forest areas into agricultural land for food production. More intensive cultivation, while maximising the exploitation of soil nutrients in the form of food grains, has meant that less has been put back in return to realise sustainable production.

Soil fertility under the traditional farming system has been maintained by repeated addition of various amounts of organic compost/manure, ranging from three to 21 mt/ha/annum (Heuch, 1986). Large amounts of compost are produced from a mixture of livestock manure, forest leaf-litter and farm waste. However, over-exploitation of forests is limiting the supply of fodder, litter and humus, and unless this trend of diminishing natural resources is checked in time, and the traditional practices of maintaining soil fertility are modified with available or improved technologies, the hill farming systems will no longer remain sustainable. Use of chemical fertilizer to cope with these losses is costly, and is generally impractical for hill farmers in any case, both because of a lack of service infrastructure to provide it, and its cost.

The alternatives are to protect and manage the remaining natural forest resources, to improve locally available technologies for increased forage production and better composting, and to utilize the farmers' own extensive indigenous knowledge of soil fertility maintenance. This chapter deals with the effects of the interaction between forage production and animals upon the replenishment of soil fertility, comparing the effects of traditional and modern approaches to the conditions in the hills of Nepal. [Continue reading at http://www.fao.org/docrep/004/t0706e/T07… ]