Land use system

village gardens, seepage gardens, drained seepage gardens, lagoon gardens and riverbank gardens

According to Fresco et al (1994), the concept of the land use system in sustainable land management embraces a set of components. Basically the system contains three parts, representing input, process and output. He added that the concept of the land use system can be broadly seen as follows:

The Input: concerns data collection, data processing, paradigm and strategic environment.

The Process: includes land allocation based on the spatial plan and five year development plan; implementing land allocation through the provision of permits for location, land use change and land use practices; and the monitoring and controlling of land use practices.

The Output: contains the objective of the land use system, namely a sustainable and optimum land use and the establishment of four orders of land management.

The goal of land use system for sustainable land management is to establish sustainable and optimum use of land for maximum prosperity of the people, both for the landowners and the community as a whole. To obtain this goal, land use management pursues what is called "four orders of land management”, they are: legal order, administration order, use order, and order of maintenance and conservation of environment. Mwale (1995) reiterated that, through this strategy, land use management will establish a land use arrangement as follows:

(a) All types of land use are accommodated according to the plan, and there will be no conflicts among them. Besides, they must be in balance and in harmony both in terms of hectares and location.

(b) All types of land use must be discerned based on the technical criteria for maximizing benefit and minimizing externalities, and must avoid any activity hazardous to the environment or which diminishes the land’s carrying capacity.

According to Stomph et al (1994), the type, timing and sequence of operations are very important for a thorough analysis of the performance, for example productivity and sustainability, of a land use system. Temporal aspects of land use must also be considered in the analysis of the temporal variation in labour demands, fertilizer requirements, cash flow, etc.

Detailed descriptions of an operation includes amongst others the type and quantity of implements used, the type, quality and quantity of material inputs applied and labour inputs used, the main power source used, and details on products/benefits achieved.

In many developing countries, agro-ecological and socio-economic conditions differ considerably in both space and time. On top of this variable environment, farmers use a wide range of production systems, resulting in a large variation in productivity across and among agro-ecological zones, and among farm types. Additionally, the low availability of geo- referenced data and information, and the often poor relations between the civil society (farmers, extension services, and Non-Governmental Organizations (NGOs) and development projects), research institutes, and decision makers have considerably limited the targeting of technologies to the specific environments, and consequently the development of sustainable agricultural production systems for larger areas in these countries. Considering that in most countries the population growth rates exceed largely the annual growth rate of agricultural production, and soil mining is almost a rule, options for agricultural development based on sustainable production systems with increased yields are urgently needed. Research has yielded alternative technologies, but transfer to villages has often failed, due to a number of reasons. Among them are the non-adaptation of technology to farmer's ability, financial constraints, low availability of

inputs, poor extension services, land tenure problems, and the non-compatibility with the extensive, individualists strategies of both crop and livestock farmers (FAO, 1995).

Van-Duivenbooden (1995) maintained that land use planning, being an integral part of farmer's practice ever since people started to cultivate crops, may provide a way to solve many of these problems. At present, land use planning means almost implicitly the development of sustainable production systems for a given region. Interactive Development Scenarios (IDS) models may be tools that outline options for development through identification of appropriate land use systems, i.e. the combination of specified land uses (or production systems) practised on a given land unit that can be geo-referenced. Figure 9 shows the schematic representation of a land use system.

Biophysical Climatological Socioeconomical Policy environment environment

- lithology - radiation - availability of labor - land use policy

- land form - rainfall - markets - subsidy policy

- diseases - temperature - infrastructure - import of

- fertilizer

Inputs and

Technologies Outputs

LAND USER

goals

knowledge AGROECOSYSTEM

etc.

WATER SOIL CROP / LIVESTOCK /

VEGETATION FISH

System’s losses:

denitrification, leaching, volatilisation, transpiration

Border of system; Flow of energy, biomass or nutrients, or physical effect Flow of information (e.g., decision criteria, values, etc.)

Figure 9. Schematic Representation of a Land Use System (after Van Duivenbooden, 1995)

To link various research disciplines, formulation of development scenarios of sustainable land use systems is considered an effective mechanism, because it requires the identification and quantification of inputs and outputs from the one and the other. The scenarios must be defined according to stakeholders (that is, for farmers, village heads, regional and national decision-makers) and for each scale (Van-Duivenbooden, 1995).

Formulation of such development scenarios permits identification of technologies and interventions at different scales and moments, and of the priorities of agricultural research.

This will lead to an improved impact of research.