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Zimbabwe
A pioneering early study at reconnaissance scale was the agro-ecological and agro-
economic survey of Zimbabwe (at that time Southern Rhodesia) (Vincent et al. 1962).
The country was first divided into agro-ecological regions, based on climate and soils,
and the predominant farming systems for each identified. These farming systems were
then subjected to agro-economic analysis. The survey was very clearly on a two-stage
basis, with the two parts conducted by different staff, and published separately.
The next two examples illustrate comprehensive development feasibility surveys,
in which all aspects of rural land development are integrated, from physical resource
surveys through economic analysis and social or participatory studies (Young 1978).
Nepal
A survey of the Nawalparisi area was carried out to assess potential for development
consequent on construction of road access to this zone (Berry 1974). Physical land
suitability was mapped at semi-detailed scale; the suitability classes were linked with
agricultural and economic data; the combined data were employed to map suitability
(physical and economic) for tea cultivation; and from the maps, potential development
areas were identified.
Gambia
A study was made of the potential for agricultural development of Gambia, with
mapping at a scale of 1:125 000 (Dunsmore et al. 1976). It included natural resource
surveys (climate, soils, ecology, hydrology and present land use), technical studies
(crop production, animal husbandry, forestry), economic analysis, and social studies
(population, land tenure, village studies, social structure). The report ends with 26
pages of recommendations for development.
Mexico
Local knowledge of soils (ethnopedology) was compared with conventional soil survey
in a study in Mexico (Ortiz-Solorio & Gutierrez-Castorena 2001). At a detailed scale,
local knowledge was transformed into a soil map that was more precise and accurate
than similar scientific maps at the local scale. At the regional scale, more problems were
encountered. Farmers in Mexico possess cartographic knowledge but their knowledge
is conceptual. They know where to find different land classes but they do not elaborate
maps. There was a need for a base map, a kind of topographic map, on which the local
land and soil units could be projected.
Bangladesh
Land evaluation surveys of immense detail were carried out in Bangladesh (Brammer
et al. 1988). In the first instance, these consisted of physical evaluation linked with
crop suitability, but it should be noted that the latter was not based only on physical
criteria but in addition, considerable use with made of local knowledge. The results
were subsequently applied to a wide range of development questions, for example
site selection for experimental stations, and village agricultural development plans
(Brammer 2002). Examples are given of how to scale down reconnaissance maps to
village (thana) scale, the detailed work at village scale being conducted by the local
agricultural extension officer.
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