Fjölrit RALA - 05.12.1999, Side 85

Fjölrit RALA - 05.12.1999, Side 85
Tamirie Hawando 83 Population pressure on the land resources The present population of Ethiopia is estimated at 62 million (Table 6) of which 88% live in the highlands. The highlands cover 44% of the country’s land area and display very rugged geomorphic features, steep slopes with narrow inter-mountain valleys as common features of Ethiopian highlands. The population has grown very fast on the limited land area in the highlands and every pos- sible piece of land is put into cultivation to pro- duce food. Means for relaxing this population pressure should be considered very seriously Use of dung and crop residues as energy Studies in energy sector by World Bank (1984) and Cesen (1986) reported that 99% of the energy used in Ethiopian homes comes from bio-mass sources which include dung, crop residues, and woody bio-mass. These studies estimated that out of the 22.5 million tons of cattle manure annually produced, 38% is used as a fuel and out of the 21.2 million tons of crop residues produced annually, 24% is used as a fuel. The re- maining 76% of crop residue is left on the ground and/or is used by livestock. Other studies in Ethiopia showed that a total of over 3 million tons equivalent of nitrogen, potassium and phosphorus are removed by livestock through grazing and crop residue consumption (NCS 1992, FAO 1984). The amount of nitrogen, phosphorus and potas- sium in the livestock manure produced annually in Ethiopia is estimated at 1.4 million tons in terms of N, P205.and K20 (Hawando 1995). Ox-plough, cereal mono-culture farming system In the dry sub-humid and semi-arid highlands, the cereal mono-culture is the most dominant farming system. Crop rotation scheme, inter-cropping, mulching and using manure on the farm fields are not normally practiced by many farmers. In addition, dung and crop residues are used as fuel and livestock feed. The farmers plow their land up and down the slopes thus exposing the soil to rill and gully erosion. The Ti- gray, Wollo, Semen Shewa, parts of Gonder, Central and South-central Rift-Valley zones, Arsi and Bale highlands are good examples of cereal mono-culture farming system. With the exception of Bale and Arsi highlands, the other cereal mono-culture areas display severely degraded land surfaces Salinity and alkalinity problems The semi-arid and arid lowlands and valleys in Ethiopia have major problems of sa- linity and alkalinity. Recent studies by Hawando (1989, 1995) have revealed that 44 million ha (36% of the country’s total land area) are potentially susceptible to salinity problems. Out of the 44 million ha, 33 million ha have dominantly salinity problems, 8 million ha have combined salinity and alkalinity problems and 3 million ha have dominantly alkalinity problems. Out of the 170,000 ha under irrigation by state farms Table 6. Populatíon estimates and projections (CSA 1988). Year Population million Annual growth rate, % 1920 12.9 0.6 1950 19.2 1.7 1970 29.5 2.3 1985 43.3 2.9 1995 60.3 3.3 2000 71.5 3.4 2010 99.6 3.3
Side 1
Side 2
Side 3
Side 4
Side 5
Side 6
Side 7
Side 8
Side 9
Side 10
Side 11
Side 12
Side 13
Side 14
Side 15
Side 16
Side 17
Side 18
Side 19
Side 20
Side 21
Side 22
Side 23
Side 24
Side 25
Side 26
Side 27
Side 28
Side 29
Side 30
Side 31
Side 32
Side 33
Side 34
Side 35
Side 36
Side 37
Side 38
Side 39
Side 40
Side 41
Side 42
Side 43
Side 44
Side 45
Side 46
Side 47
Side 48
Side 49
Side 50
Side 51
Side 52
Side 53
Side 54
Side 55
Side 56
Side 57
Side 58
Side 59
Side 60
Side 61
Side 62
Side 63
Side 64
Side 65
Side 66
Side 67
Side 68
Side 69
Side 70
Side 71
Side 72
Side 73
Side 74
Side 75
Side 76
Side 77
Side 78
Side 79
Side 80
Side 81
Side 82
Side 83
Side 84
Side 85
Side 86
Side 87
Side 88
Side 89
Side 90
Side 91
Side 92
Side 93
Side 94
Side 95
Side 96
Side 97
Side 98
Side 99
Side 100
Side 101
Side 102
Side 103
Side 104
Side 105
Side 106
Side 107
Side 108
Side 109
Side 110
Side 111
Side 112
Side 113
Side 114
Side 115
Side 116
Side 117
Side 118
Side 119
Side 120
Side 121
Side 122
Side 123
Side 124
Side 125
Side 126
Side 127
Side 128
Side 129
Side 130
Side 131
Side 132
Side 133
Side 134
Side 135
Side 136
Side 137
Side 138
Side 139
Side 140
Side 141
Side 142
Side 143
Side 144
Side 145
Side 146
Side 147
Side 148
Side 149
Side 150
Side 151
Side 152
Side 153
Side 154

x

Fjölrit RALA

Direkte link

Hvis du vil linke til denne avis/magasin, skal du bruge disse links:

Link til denne avis/magasin: Fjölrit RALA
https://timarit.is/publication/1497

Link til dette eksemplar:

Link til denne side:

Link til denne artikel:

Venligst ikke link direkte til billeder eller PDfs på Timarit.is, da sådanne webadresser kan ændres uden advarsel. Brug venligst de angivne webadresser for at linke til sitet.