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Text 4D Matching land use requirements with land qualities A kind of land use should be described in terms of its products and management practices. The description must be sufficiently detailed to assess its land use requirements and to plan the necessary inputs. It must include the description of conditions which are potential con- straints for production. The physical requirements of a specific land use type are water, nutrients, temperature regime, salt tolerance. Based on the identifica- tion of limiting values which are critical for yield levels, we divide yield levels into classes according to growth requirements and poten- tial changes in external inputs in the land use system. Land use requirements should be identified according to the fol- lowing criteria: - The land should be able to support the land use on a sustained ba- sis; - The use should yield benefits that justify the inputs. To meet land suitability a land use planner is to be able to separate suitable land from unsuitable according to sustainability and profit- ability. Trials and experience of land users must be used choosing the plot of land. Land suitability classes reflect degrees of suitability. Lands are subdivided into classes according to their degree of suitability and magnitude of changes required to achieve a satisfying level of produc- tivity. Land suitability subclasses reflect kinds of limitations, or main kind of improvement measures required within classes. A land use planner is to identify limitations which may be reduced by specific improvements. E.g. land unit evaluated as subclass S2e means erosion 43 hazard and land unit evaluated as subclass S2w means inadequate wa- ter availability. After matching land qualities and land use requirements, we can prepare options for development in the form of land use system, which include descriptions of bio-physical requirements and the socio- economic characteristics of different land use types. Land use system includes the combination of a land unit and a land use type. Outputs are presented to land users and decision makers as land suitability maps and descriptions of land use types. жүктеу/скачать 0.91 Mb. Достарыңызбен бөлісу:
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