Nepal lies on the southern flanks of the central Himalayas as an 835 km long and 90 to 230 km wide strip of land comprising an area of 147,181 kmē. Within this small area, Nepal has differences in altitude of over 8,500 m like no other country on earth. From the border to India in the south the land rises from the humid-hot plains of the Terai with an altitude of around 100 m above sea level upwards towards the north. Over the foothills of the Churia Range and the Mahabharat Range with altitudes of up to 2,000 m, the country opens up into the broad upland valleys of the central country which lies at altitudes of between 1,000 and 2,000 m, has a temperate sub-tropical climate and provides settlement area for the majority of the population. Further north then come the mountainous regions of lower and the central Himalayas. In the central Himalayas or upper Himalayas where the country borders on Tibet, with eight mountains of over 8,000 m, is also Sagarmatha, or Mt. Everest, which at 8848 m is the highest mountain on earth. Expressed in percentages, the Terai covers 17%, the central mountains 68% and the uplands 15% of the total area of land.
Like in India, the climate is dominated by the monsoons bringing rain from June to September from the south. During the rest of the year dry winds from Central Asia are predominant and prevent precipitation. The amount of precipitation depends on the altitude. Between 2,000 and 3,000 mm of rain fall on the central mountains; precipitation in the upland valleys amounts to 1,500 mm annually. Temperatures too show a similar variation: in the upland valleys the minimum temperature in December and January falls to freezing point at night in December and January with temperatures during the day of between 16° and 20°C. In the hills and the high Himalayas temperatures vary far more. Settlement reaches altitudes of up to 4,000 m where minimum temperatures of -10°C are reached. Biogas plants are operated up to altitudes of 1,500 m.
Nepal has a population of about 18 million. The calculated density of the population amounts to 115 inhabitants per kmē, however, the area which can be settled is far smaller so that the true density amounts to around 440 inhabitants per kmē. Population growth is 2.7% per year.
Agriculture and tourism are the main sources of income in the country. Agriculture contributes around two thirds to the GDP; income from tourism amounts to about 17%. The state budget is in deficit and is financed by means of funds from international development aid to approx. 40%. With an annual per capita income of approx. 300 DM, Nepal is one of the poorest countries in the world. These figures, however, considering the living situation of the majority of the population are not an adequate indicator of prosperity since most of the inhabitants in rural areas carry out subsistence farming. The inadequate infrastructure of the country is considered to be the main reason for the low productivity in agriculture.
Over 90% of the population in Nepal live from agriculture. Rice, sugar cane, maize, sorghum, oilseed, barley, wheat, tobacco and tea are the most important products. 80% of all exports are or are based on agricultural products. Agricultural production is not sufficient to provide adequate foodstuffs for the inhabitants due to the geographical and climatic conditions and the rapid growth rate of the population. The structure of Nepal's agriculture is mainly that of small-scale farms. The average size of farm is around 0.5 hectares in the "hills" (central mountains and lower Himalayas) and about 1.5 hectares in Terai. Animal production is not an inconsiderable factor in enhancing the arable crops, but meat production for religious reasons is limited to sheep and goats; cattle and water buffalo are mainly kept for dairy products and as draught animals. There are estimated to be around 12 million of the latter; stabling is widespread due to difficult terrain conditions. Cattle dung is sought after as a raw material for fuel and fertiliser.
The total energy requirements of the country is estimated to be 252 million GJ annually. The largest proportion is used for consumption. The primary source of energy used for productive purposes in agriculture is still human and animal labour.
Decades of ruthless exploitation of the forests in the Himalayas which are endangered by erosion as it is, have left behind massive, ecological imbalance. The increasing pressure of the population is affecting isolated parts of the country where organised timber thefts are diminishing the resources of local populations to a great extent. Subjected to uncontrolled felling and sparse re-afforestation measures, the countryside is falling victim to erosion. Also the use of existing forests as pastures for cattle or for obtaining feedstuffs is causing great damage. Also the Terai, which was densely forested until well into the fifties, the claiming of land for cultivation has led to a situation equal to complete deforestation.