Land Use Systems, Analysis and Planning

Human beings make use of the land they inhabit to a degree unmatched by any other species. Anyone who has flown in an aeroplane can attest to the extent to which people have modified the landscape below to suit their own purposes. The human imprint is most marked in the temperate and tropical zones, but even remote deserts, high mountains, and

Polar Regions bear evidence of the works of people. Land represents about 29 per cent of the Earth's surface. The uses to which this land is put known as land use morphology vary considerably from place to place. In the continental United States, for example, land is more or less equally divided amongst forest, pasture, crops, and built-up areas. By contrast, 75 per cent of the land in the Democratic Republic of the Congo is forested, and only about 10 per cent is devoted to crops and pasture.

Ahmed and Sanders (1998) regarded land use as the various ways by which man utilizes the land resources at a given time period. In other words it has to do with series of operations on land, carried out by humans, with the intention to obtain products and benefits through using land resources. Land use is therefore, the primary indicator of the extent and degree to which man has made an impression on the earth’s surface. It reflects political, social and economic aspects of human culture and provides an index of the intensity of human life style.

Land use is characterised by the arrangements, activities and inputs people undertake in a certain land cover type to produce, change or maintain it (FAO, 2005).

Knowledge of current land use (& land resources) is needed for formulating changes leading to sustainable use of the resources. Land use information provides answers to one or more of the following questions concerning the current use of the area:

i. What: the purpose of activities undertaken - the specific products and services, that are sought

ii. Where: the geographic location and extent of the spatial unit under consideration iii. When: the temporal aspects of various activities undertaken - the sequence of

carried out operations like planting, weeding,

iv. How: the technologies employed - technological inputs and materials such as fertilizer, irrigation, labour,

v. How much: quantitative measures - areas, products

vi. Why: the reasons underlying the current land use –land tenure, labour costs, market conditions.

According to Barlowe (1978), the activities of man on land take place within a threefold framework. These frameworks involve the impact that physical and biological factors, economic considerations, and institutional arrangements have on private and public decision relative to land use. Together, these three groups of factors set the limit as to what individuals, groups and governments can accomplish with any given level of technology in their development utilisation and conservation of land resources. This is to say that land use is the purpose the land serves, for example, recreation, wildlife habitat, or agriculture. Land use applications involve both baseline mapping and subsequent monitoring, since timely information is required to know what current quantity of land is in what type of use and to identify the land use changes from time to time. This knowledge will help develop strategies to balance conservation, conflicting uses, and developmental pressures. Issues driving land use studies include the removal or disturbance of productive land, urban encroachment, and depletion of forests.

Precise descriptions of land use are needed for sound analysis of land use performance, notably its feasibility, productivity, sustainability, and environmental impact.

The performance of land use can only be determined if land use is described for a known location and a known period of time. This means that spatial and temporal boundaries of the land use must be defined. Actual land use must be described as part of a system. If land use pattern change is to be a possible option for meeting increasing needs for food production or

to mitigate declining yields, a larger area must be brought into cultivation. This can be done by decreasing the ratio between fallow and cultivated land within a given village territory or by including new territory for cultivation. One obvious premise for this is that idle, uncultivated land must be available within an acceptable distance to the farmer. Whether this is the case is, however, influenced by social and cultural parameters which enable and constrain access to land.

Land is an element of land use systems and thus referred to as the compounded properties of climate, soil, terrain, flora and fauna (including crops, weeds, diseases, livestock, wildlife, and pests) and the results of past land use (notably infrastructure). Aspects of land are very important for precise analysis of the performance of a land use system.

Databases containing land information, for example, on soil, land cover, or climate, may be linked with the Land Use Database in order to carry out land use systems analysis.

Nonetheless, some aspects of land can be stored in The Land Use Database. It concerns notably infrastructure and selected observations. Infrastructure is defined as: "Permanent installations constructed to assist economic activity such as roads, irrigation or drainage works, buildings and communication systems." (FAO 1993)

Infrastructure present in or around a plot may be used in the context of a particular land use. In The Land Use Database, information on such infrastructure can be stored. A system is therefore, defined as: "A limited part of reality with well-defined boundaries that contains interrelated elements, where the elements within the boundaries have strong functional relations with each other, and limited weak or non-existent relations with elements in other systems" (De Wit, 1993). If this definition of a system is adopted, a land use system is thus, defined as: "A specific land use, practised during a known period on a known and contiguous area of land with identical characteristics." To study the

performance of land use(s), a land use system must be the basic entity of description.

Previous studies (Omojola and Soneye 1993, Usman 1991) have confirmed that a good knowledge of land use of any given geographical area has to do with the human activities on land, the facilities placed on land, the effects of such human activities on the environment, and the actual people making use of the land under consideration.

According to Saha and Pande (1990), the constraints imposed by geography, population density, climate, and other factors make usable land an especially precious commodity in some countries. In the low-lying Netherlands, strenuous efforts have been made to increase the amount of land available for economic use by reclaiming large areas from the sea. Similarly, in Japan, where most of the population is crowded onto the narrow coastal plains that lie between the mountainous interior and the sea, engineers create additional land by filling bays and harbours. In Bangladesh, devastating floods arrive with depressing regularity. They are the result of extensive deforestation in the mountains upstream, torrential monsoon rainfall, and occasional tidal waves in the Bay of Bengal.

Combined with slowly rising sea levels, these forces threaten to reduce permanently the land area available for human habitation.

Information generation from remotely sensed data captured by various types of sensors flown aboard different platforms at varying heights above the terrain, and at different times of the day and the year, does not lead to a simple classification. To date the most successful attempt in developing a general-purpose classification scheme comparable with remote sensing data has been done by Anderson (2002). Many of the other classification schemes used with remotely sensed data are modification of the Anderson’s classification which suggest that classification system should recognize both activities (land use) and resources (land cover) of the area under study. Such a land use classification that utilizes satellite remote sensing

data should meet the following criteria:

a) The minimum level of interpretation accuracy using remotely sensed data should be at least 95%

b) The accuracy of interpretation for the several categories should be equal

c) Repeatable results should be obtainable from one interpreter to another and from time of sensing to another

d) The classification system should be applicable over extensive areas

e) The categorization should permit land use to be inferred from the land cover types

f) The classification should be suitable for use with remotely sensed data obtainable at different times of the year

g) The categorization should be dividable into more detailed sub-categories that can be obtained from large imagery or ground surveys

h) Aggregation of categories should be possible

i) Comparison with future land use and land cover data should be possible, j) Multiple uses of land should be recognized when possible.

In most countries, increasing pressure to use land for economic development is leading to conflict. Farmland, wetlands or other land close to cities are been sought by developers to convert into suburbs, motorways, or shopping centers. Conservationists may resist efforts to level natural forests and replace them with tree plantations, ranches, or farms.

Developing countries in particular are frequently faced with a dilemma. Their need for money leads them to liquidate their forests and modify their savannahs to obtain timber, beef, tea, rubber, and other cash crops for export, yet they must conserve these same ecosystems to guarantee resources for the future.