Land Evaluation: An Essential Step Toward Sustainable Agricultural Production

Land evaluation aims to assess how land behaves when used for certain purposes. It involves carrying out and interpreting baseline studies on climate, soils, vegetation, and so on, in relation to the requirements of various uses. For all practical planning purposes, only uses compatible with the physical, economic, and social characteristics of the area in question should be considered, while also taking economic factors into account.

Purposes of land evaluation

Although land evaluation can, in some cases, focus on current land behavior, it more often deals with changes to land use and, at times, to the land itself, along with their effects.

Evaluation takes into account the economic aspect of proposed activities, as well as their social consequences for the population of the area and country in question, and their effects, whether beneficial or harmful, on the environment. It must therefore answer the following questions:

• How is the land currently managed, and what will happen if current techniques remain unchanged?
• What improvements could be made to current land management techniques while continuing to use the land in the same way?
• What other uses are physically possible and economically and socially compatible?
• Which of these offer ongoing production potential or other benefits?
• What are the harmful effects, from a physical, economic, and social standpoint, of each mode of use?
• What renewable inputs are needed to achieve the desired production and minimize harmful effects as much as possible?
• What are the benefits offered by each mode of use?

When introducing a new type of use involves a significant change to the land itself - such as irrigation projects, for example - the evaluation must also answer the following questions:

• What changes to the condition of the land are possible and necessary, and by what means can they be achieved?
• What non-renewable inputs do these changes require?

The evaluation process is not meant to determine what changes should be made to a given mode of use, but rather to provide data to support decision-making on the matter. To be effective in this role, the results of an evaluation should, in principle, take into account several possible uses for each area of land, and include information on the beneficial and harmful consequences of each.

Land evaluation and land-use planning

Land evaluation is only one part of land-use planning. Its precise role varies depending on circumstances. In the present context, the land-use planning process refers simply to a series of general activities and decisions, namely:

1. recognizing the need for change;
2. identifying objectives;
3. formulating proposals offering several possible uses and establishing their main requirements;
4. identifying and delineating the different land types in the area in question;
5. comparing and evaluating each land type against the various modes of use;
6. selecting the optimal mode of use for each land type;
7. drawing up a project, or carrying out any other detailed analysis of a set of alternative solutions for the various parts of the area; in some cases, this takes the form of a feasibility study.
8. deciding on implementation;
9. implementing;
10. monitoring implementation.

Land evaluation plays a major role in steps 3), 4), and 5) above, and provides information for subsequent activities. Before proceeding with land evaluation, it is therefore necessary first to recognize the need to change how the land is used; this may involve developing new types of productive use, such as agricultural development or forest planting projects, or providing services such as the creation of national parks or recreational areas.

Once this need is recognized, the objectives are identified and general and specific proposals are formulated. The evaluation process itself involves describing a range of promising uses, as well as assessing them against each land type identified in the area in question. This makes it possible to recommend one or more preferred modes of use. These recommendations can then be used to decide which uses best suit each part of the area. In later stages, these are generally studied in more detail, and then, if it is decided to move forward, the development project or other type of change is implemented, and the results are monitored.