CONCEPT AND APPROACHES OF LAND EVALUATION BehzodAbdullobekov Tajik Agrarian University August 16, 2012, Hungary
Lecture content • Land evaluation procedure • Land capability classification • Land productivity index
What is land evaluation? • Land evaluation is aimed at assessment of land performance and its production potential for a specific purpose. • Land evaluation is only part of the process of land use planning. • The function of land use planning is to guide decisions on land use in such a way that the resources of the environment are put to the most beneficial use for man, whilst at the same time conserving those resources for the future.
Land-use requirements Landqualities match suitability Land-useplanning policies & plans Land Evaluation Structure
Land Evaluation Methods • Land Capability Classification • Soil and Land Irrigability Classification • Parametric methods Land Productivity Index Soil Productivity Index
LAND CAPABILITY CLASSIFICATION • There are eight capability classes • Class I to class IV : Arable land (suitable for cultivation) • Class V to class VIII: Non-arable land (unsuitable for cultivation) • The subclass are based on kinds of dominant limitation such as wetness or excess water (w), Climates (c) and erosion (e)
Land Productivity Index (Stories Index) Land Productivity Index (LPI)= A*B*C*X*Y Where factors are decimal equivalents of percentage ratings. • A = General characteristics of soil profile • B =Texture of the surface soil • C = Slope of the land • X = Miscellaneous factors; reaction of surface soil, fertility, erosion • Y = Average annual rainfall
LAND IRRIGABILITY CLASSES The suitability of land for irrigation depends on physical factors like quality and quantity of irrigation water and socio-economic factors like land development costs provision of drainage facilities production costs of individual crops. ClassDefinition Class 1 Lands that have few limitations of soils, topography or drainage for sustained use under irrigation. Class 2 Lands that have moderate limitations of soil, topography or drainage for sustained use under irrigation. Class 3 Lands that have severe limitations of soil, topography or drainage for sustained use under irrigation. Class 4 Lands that are marginal for sustained use under irrigation because of very severe limitations of either soil topography or drainage. Class 5 Lands that are temporarily classed as not suitable for sustained use under irrigation. Class 6 Lands not suitable for sustained use under irrigation.
Selected project districts represent both Kurgan-Tyube and Kulyab Cadastre zones
FAO Framework of Land Evaluation In the FAO land evaluation procedure, land qualities/land characteristics of each land unit are compared with land use requirements (LURs) to obtain an overall suitability assessment of the land unit for each of land utilization types (LUTs) FAO Framework classification describe the suitability of an evaluation unit for a land use in four categories, - Order - Class - Sub-class - Unit
Framework of Land Evaluation Assess land suitability based on: • the requirements of specific land uses • a comparative analysis of inputs vs. benefits: multi-disciplinary • the physical, economic and social context • potential environmental impacts & sustainability Local to global scales, highly populated to undeveloped areas, qualitative vs. quantitative.
(1) Suitability orders All land is divided into two suitability orders, according to whether the land is suitable or not for a given LUT. 'S' = suitable, 'N' = not suitable, for the land use. (2) Suitability classesThese are divisions of suitability orders that indicate the degree of suitability, not simply suitable vs. not suitable. 'S1' = suitable, 'S2' = moderately suitable, 'S3' = marginally suitable, 'N1' unsuitable for economic reasons but otherwise marginally suitable, 'N2' = unsuitable for physical reasons. N3implies limitations that are not correctable at any cost within the context of the land utilization type.
Suitability for rice Khatlon region Shurobod Vosedistrict Temurmalik
Land evaluation: conceptual steps Consultation • Objectives • Assumptions • LU options Interimmatch Land-use requirement Landqualities LUT Land mapping Unit Interim SuitabilityAssessment classification system Final SuitabilityAssessment • land improvements • environmental impacts • Social and economic analyses
LandEvaluation Land Evaluation applications Agricultural development planning Irrigation suitability assessment Population supporting capacity Agricultural technology transfer Livestock forage balance assessment Land degradation risk assessment Environmental impact assessment Agricultural inputs recommendations
Student tasks Topic: To do restorative plan the land cadastre map Practices material : Old cadastre map of Khatlon region. Check the accuracy of updating Report of procedure Reference/