4. LAND

4.1 GENERAL CONSIDERATIONS

In this text the following definition of land is used (Brinkman and Smyth, 1973): a tract of land is defined geographically as a specific area of the earth's surface: its characteristics embrace all reasonably stable, or predictably cyclic, attributes of the bioshere immediately above and below this area including those of the atmosphere, the soil and underlying geology, the topography, the hydrology, the plant and animal populations and the result of past and present human activity, to the extent that these attributes exert a significant influence on present and future uses of the land by man.

As mentioned earlier the land situated below the 465 contour was studied in particular.

4.2 CURRENT LAND USE

Most intensive use of the draw-down areas is made in the northeastern branch of the Lake, which really constitutes a somewhat enlarged Niger River channel. Most of the resettlement villages are in this area also. Cultivated areas mainly occur in the vicinity of the villages, and acreages vary commonly between 0.1–5.0 acres. Upland rice and onions are the dominant crops but some vegetables and groundnuts are grown in addition. In this area people have got used to the new conditions created by the lake and cultivate most of the crops known to them prior to impoundment (Adalemo, 1972).

Cultivation usually commences when the water level drops to use the moisture retained in the soil by flooding. Lake planted crops may also benefit from the beginning rains (see Fig. 2). The hoe is frequently used and little fertiliser is applied.

Larger areas around the central lake are not cultivated mainly 1) because there was no need to do so; 2) most of the people are fishermen and agriculture is carried out at subsistence level; 3) unfamiliarity with the situation created by the lake as to what farming practices are best applied; 4)lack of capital to develop larger areas; 5) inaccessability of a large part of the draw-down area from the land side.

4.3 LAND CLASSIFICATION

In order to arrive at an evaluation of the land the physical factors must be known. Interpretation of these data may be related to 1) the current conditions of the land, 2) the conditions that might potentially prevail if major improvements were to be made or 3) to a comparison of both situations.

The socio-economic factors relevant to the development of the draw-down areas are not commonly known. Although guidelines are being drawn up by the FAO for a new approach to land evaluation, it was felt premature in the light of the present information to use this not yet finalised system. The USDA classification as developed by the U.S. Bureau of Reclamation is applied for the land of the draw-down areas. In terms of irrigation practices these lands are subject to wild, uncontrolled flooding once a year. Little is done to control the flood-water by means of bunds or dykes to either keep the water out of certain areas or to prevent it from streaming away from flooded terrain so as to keep it longer saturated.

The given land classification is valid for current use of the land and given in qualitative terms. On reconnaissance level three classes are distinguished which warrant the extent, location and quality of arable areas with the object of obtaining sufficient information from which to determine the justifications of making detailed observations.

Class 1 - suitable: lands that are highly suitable for irrigation farming, being capable of producing sustained and relatively high yields of a wide range of climatically adapted crops at reasonable cost. Land in this class has almost flat to very gentle sloping topography, little or no effects from past or present erosion, deep (moderately) well drained fine loamy or clayey soils, open grass vegetation and good accessibility. Up to 15 percent of Class 2 or 3 is included in this wait.

Class 2 - moderately suitable: lands of moderate suitability for irrigation farming; they are not so desirable nor of such high value as lands of class 1 because of certain correctable or incorrectable limitations. This class includes lands of steeper topography, moderate effects from past or present erosion, moderately deep or shallow soils, which may contain gravel, have variable textures and are under vegetation of grasses in combination with stunted woodland or shrubs. Accessibility is difficult sometimes. Up to 15 percent of Class 1 or 3 is allowed in this unit.

Class 3 - unsuitable: lands in this class include those considered non-arable under the existing project or the project plan because of failure to meet the minimum requirements for the other classes of land. Lands have steep slopes, very shallow soils or lithosols in combination with rockout-crops and gravel, and are subject to severe erosion or have been subject to severe erosion resulting in truncation of profiles and gully formation. Access to this land is variable, the vegation mainly consists of grass. It would be useful to incorporate the time of exposure of the draw-down at the various levels in the terms for the land evaluation criteria. This is however hindered by the fact that there is considerable variation between maximum and minimum lake-levels from year to year (Fig. 3). In general an exposure time of four months or longer occurs above the 455 feet contour. The cultivation of upland crops is therefore restricted to this area.

This report is accompanied by a reconnaissance land suitability map at scale 1:100.000. The land suitability classes are indicated as follows:

Class 1		suitable
Class 2		moderately suitable
Class 3		suitable

Also indicated on the reconnaissance map are the soil associations as discussed in Section 3 of this report. Table 6 facilitates the place of the various soil series within the land suitability classes.

Table 6

Land suitability classes and associated soils associations/series

4.4 ACREAGE OF THE DRAW-DOWN AREA

The proper draw-down area feasible for more intensive farming in situation between 455–465 contour. It comprises 46 714 acreas (19 153 ha). The area between 465–475 feet contour comprises a considerably large surface - 88 511 acres or 36 289 ha. However, cultivation in this region is based on rainfall with or without irrigation, some capillary rise of the groundwater table due to the rise in the lake water and some lateral and surface drainage from the higher associated areas. The area is considered a transition between the proper draw-down and the upland areas. The latter form a substantial area of many thousands of hectares around the central Lake Basin and are usually associated with suitable draw-down. If the higher (465–475 feet) and the lower (455–465 feet) lying areas are taken into account the area suitable for irrigated arable farming is estimated at 12 197,24 ha, the area moderately suitable has the same acreage, while the area unsuitable takes up about 56 percent of the total draw-down area being 31 047,52 ha. Thus:

Associated upland areas (>475 ft) suitable for irrigated agriculture in the Papiri and Gafara areas was estimated at between 2 000–2 400 acres and 2 000–4 000 acres (respectively 902 and 1 230 ha on average), Klinkenberg (1973).

4.5 LAUD MANAGEMENT AND CROP YIELDS

The cultivation of the draw-down area is in the first instance controlled by the variation in lake level and secondly by alternative water supplies.

For the upland areas, which fall outside the lake water influence, rainfall is the main source of water, although in some cases this may be supplemented by irrigation. The transitional area between these two receives water from the rainfall, from lateral drainage of the upland areas and from the lake through a rise in ground-water table in the draw-down areas. The extent of this area may vary considerably as its water supply is solely based on a large number of variables.

The following farming operations are visualised (see also Fig. 6)s

In the draw-down operations, rice can be grown throughout, as its planting follows the downward movement of the water level. Upland crops follow the rice-crop in those areas which are relatively drier. Planting operations are done in strips following the receding water. Rice can be cultivated with or without bunding, thus with or without water conservation. In both oases suitability of the land depends apart from its slope, upon 1) the water holding capacity of the soil and 2) the groundwater movement.

When the water comes up (draw-up) floating rice can be planted, as long as the daily rise of the water does not exceed 18 cm. In the higher part of the area upland rice can be grown.

In both types the lowest area is the wettest and offers only limited scope for crop production. Kaul (1973) reports on good results of water melons in rotation with deep water paddy.

The upland areas are normally farmed under rainfall conditions. Although an increasing acreage of land is being brought under irrigation, the irrigation water is best used during the dry season when crop production is economically favourable because of low food supply from other sources.

Plant growth in the transition zone may mainly depend upon rainfall. However deep wafer crops are able to tap the water in the (deep) subsoil which originated from the rising lake level and/or drainage from the upland. Pigeon Pea as well as citrus trees were reportedly doing well in this area (Kaul 1972). In Ghana (Lake Volta draw-down) cassava, cotton, groundnuts in addition are grown (FAO, 1972).

A cropping pattern, partly based at the framework as outlined above, was developed by Kaul, FAO agronomist, and is being tested at present. These patterns should be based at most effective use of the available water sources. This is to prevent soil moisture stress which adversely affect plant growth especially when it occurs at the initial stages (Babalcla et al. 1973).

Yield data at various crops as reported by Kaul (1972, 1973) are obtained from two pilot draw-down areas at Papiri and Gafare.

Between 461–465 feet contour, maize, groundnuts and rice were tried. Yields of the first two crops were in general higher at the higher levels (464–465 feet contour) while higher rice yields are obtained from the lower levels.

This indicates the sensitivity of these crops to water burden. Experiments carried out by Moormann (1973) with maize as a “valuator” crop could be conducted in the draw-down to determine the production capability of these areas.

In addition, upland rice planted between 461–465 feet contour yielded higher than the deep water (floating) rice, planted between 455–460 feet contour.

Other crops planted are watermelon (466 feet), onion (466 feet) and cotton (466–468 feet). Unfortunately, no data are available on yields of crops grown between 455–465 feet apart from rice.

It is thought advisable to extend the draw-down experiments not only in depth but also to associate them physically with the upland irrigated or rainfed sone.

4.6 ALTERNATIVE USE OF THE DRAW-DOWN AREAS

As was touched upon in earlier chapters the draw-down areas could be utilised for other than specifically crop cultivation practices.

Little information is known about other aspects but the following alternative uses are suggested:

1. possibility of grating lands for cattle in tse-tse free areas;

2. possibility of fish-breeding grounds and fish catching, even when rice is used as fish fodder crops;

3. establishing of bird-life sanctuaries in some areas, for example on the east shore of Foge Island.

4.7 DEVELOPMENT AREAS

Most of the smaller areas suitable for draw-down agriculture have been brought into use around villages. As population increases more land is needed for crop production. Small plots (up to 5 acres) could be developed locally with the aid of the agricultural officers. These should be able to rely on data made available by the project to give proper information to the farmers about draw-down agriculture.

Most of these suitable areas are to be found in bays and inlets, primarily in the drowned valleys of the Niger tributaries.

There, lands are alluvium associated with a mixture of upland soils and provide a good medium for plant growth. Larger areas were reported near Kokoli and along the east coast of the Central Lake Basin, especially in the bay south east of Gwamna and from Ruwan Gashi to Suara, and from Suara to Wara.

These warrant detailed surveys seem suitable for large scale development. Especially, the area between Raishe and Wara warrants further investigation as it is conditioned for rice. Soils are deep, poorly drained black clay associated with some coarser textured soils. The reason that no farming was carried out in this area prior to the impoundment is to be attributed to the custom of the local people, who preferred the sandier higher upland soils (Pullan et al. 1964).

It is suggested that the survey, aerial and ground, of these areas is associated with locations downstream of the dam, which were recommended by the Land Resources Division (1972).