The Challenge of the LE Toolbox

Transcription

1 The Challenge of the LE Toolbox The need to fine-tune it s use and functionality by C.A. de Bie - ITC

2 Introduction to Sustainable Land Management (4 slides) Basic Land Evaluation Concepts Step-by-step LE Weaknesses Conclusions

3 The problems Natural Resource Management Common Problems and Conflicts Resource Exploitation (food, employment, income) versus Government Priorities versus Resource Conservation (conserve resources for future uses, maintaining ecological diversity) Needs / Priorities of local people

4 Our Mandate To address tasks as put on record by UNCED in Rio (1992; Agenda 21, Chapter 10), identify options to solve future food requirements understand and combat environmental degradation we need practical concepts and approaches to gather, manage, classify and map land use systems information to study various aspects of present day land use systems

5 Our Specific Goals Assessment which land uses are relevant for which tracts of land and present needs for which tracts of land and present needs Assessment by land use type, which management minimizes environmental impacts while maximizing productivity Through LE? Other Toolbox?

6 Our General Framework The pressure-state-response framework (Modified from Pieri et al. ; World Bank Discussion Paper 315) Pressure State Response Resources Land Use Pressure State of Land Quality Change Initial Modified Response Society (Incl. land users) Modifications to land use (incl. land use conversion)

7 Our Hypothesis Performance =f ( land, land use ) Yield Observations on land (soil) by the surveyor / land user Impact on land e.g. erosion, bulk density, or salinity data Data on management Survey data Interview data Technology transfer

8 Introduction to Sustainable Land Management Basic Land Evaluation Concepts (5 slides) Step-by-step LE Weaknesses Conclusions

9 The Original LE Concept Land Use System Land Use Type Land Unit Land Improvements Outputs Inputs Land Use Requirements Land Qualities Land problems: - limits growth - reduces yields Land use aims to modify land to reduce the land problems

10 LE matches Supply and Demand Land Characteristics Land Units The Land Qualities (LQs; supply side) one table for each LUT Crop Requirements LQ s (demand side) diagnostic factors Purpose(s) s1 Factor Ratings s2 s3 n The Land Use Requirements (LURs) Yield ranges Matching

11 and LE performs a Socio-Economic assessment LUS Supply Demand Land Unit Soil / terrain related LQs Climate related LQs Bio-physical assessment Crop ecological requirements Management requirements Conservation requirements LUT requirements Socioeconomic assessment Holding and regional systems

12 but Land is much more than Soil! Land Soil / Terrain Climate / Weather Vegetation (Crops / Flora) Wildlife (Fauna) Infrastructure Land Any delineable area of the earth's terrestrial surface, involving all attributes of the biosphere immediately above or below this surface, including those of the nearsurface climate, the soil and terrain forms, the surface hydrology (including shallow lakes, rivers, marshes, and swamps), near-surface layers and associated ground water and geo-hydrological reserve, the plant and animal populations, the human settlement pattern and physical results of past and present human activity (terracing, water storage or drainage structures, roads, buildings, etc.) (FAO 1994,1995,1998).

13 and Land Use definitions are confusing! Land Use Type (LUT) 1. A kind of land use described or defined in a degree of detail greater than that of a major kind of land use (q.v.). (FAO 1976, 1983, 1985) In the context of agriculture, a LUT refers to a crop, crop combination or cropping system with a specified technical and socio-economic setting (FAO 1983,1985). 2. A kind of land use described in sufficient detail so that the necessary inputs and management options can be planned, and the outputs estimated (FAO 1991). 3. A specific way of using the land, actual or alternative, described for the purpose of land evaluation in the following terms of key attributes: produce (e.g. kind of crop), labor, capital, management, technology, and scale of operations. It is a technical organization unit in a specific socio-economic and institutional setting (Beek 1978). 4. A use of land defined in terms of a product, or products, the inputs and operations required to produce these products, and the socio-economic setting in which production is carried out (FAO 1998). Major kind of land use A major subdivision of rural land use, such as rain-fed agriculture, annual crops, perennial crops, swamp rice cultivation, irrigated agriculture, grassland, forestry, recreation (FAO 1976,1983,1985).

14 an alternative LUS concept? Context Socio -Economical Conditions Bio-Physical Conditions Land User(s) Goals Requirements & Suitability Productivity Outputs / Benefits Land Use System Land Soil / Terrain Climate / Weather Vegetation (Crops / Flora) Wildlife (Fauna) Infrastructure Land Use Impact on land ( or - ) Land Use Purpose(s) Operation Sequence Decision making / planning Inputs / Implements Impact on/from the environment Other Land Use Systems Interaction with secondary production systems Livestock Systems

15 Introduction to Sustainable Land Management Basic Land Evaluation Concepts Step-by-step LE Weaknesses (11 slides) Conclusions

16 Use Key Attributes to select LUT s for evaluation? Or are Key attributes used to describe LUT s?

17 a method to use Key Attributes to select LUT s? Field level Low farm income Low crop yield Declining soil fertility Problem tree Zone-X Area Zone-X Problem Analysis Interest Groups Government Farmer Key Problems -low productivity -low income - soil deterioration land use change - High use of inputs - Increase yields - Use fertilizers - Practise soil conservation Objectives context change - Improve availability of inputs - Provide extension advise - Provide credit Low use of inputs No soil conservation formulated in terms of key attributes LUT Selection Queries Shortage of inputs Lack of knowledge land use land use context Present problem LUTs LUT-1 LUT-2 LUT-3 LUT-4 Purpos e(s) Key Attributes Operation Sequence As at present Context Are inputs high? o -- Are yields high? - - o Are NPK s used? Soil conservation? o -- Inputs available? Extension ok? o -- Credit available? - - selected to evaluate? Always Yes Alternative LUTs LUT-5 LUT-6 LUT-7 As if done o - o o - o - o -- state for each its relevance by LUT in terms of: ( --, -, o,, ) Yes* No Yes* * But make inputs available!

18 Knowledge about Crop and LUT Requirements is limited! Technology Transfer!

19 Ecocrop is a Toolbox to select crops (not LUT s)! What about other LUT requirements?

20 Do land resources surveys cover all supplying conditions?

21 Do soil maps report by LQ all required land characteristics?

22 Which LQ s to evaluate.often sub-optimal!

23 How to measure/estimate selected LQ s?

24 Are then all interactions accounted for?

25 Combining Partial Suitabilities use Law of Liebig?

26 Do we believe that results are really fit to be used for LUP? Or are results a scientific contribution to define an agricultural research plan?

27 Introduction to Sustainable Land Management Land Evaluation Concepts Step-by-step LE Weaknesses Conclusions (3 slides)

28 We hardly dealt with improving existing systems Yield limiting / reducing factors not controlled at the research station Yield Gap-0 Non-transferable technology Environment and management constraints Yield Gap-1 Simulated potential research station yield Lack of inputs farmers risk aversion strategies Experimental maximum research station yield Technical on-farm ceiling (= Potential farm yield) Market access Prices Diminishing returns Economic on-farm ceiling Actual on-farm yield Gap-2 Gap-2A Gap-2B This level may differ considerably from plot to plot. The question which management option to address a specific land constraint is not evaluated?

29 We did not study Land Use System performances in the field Yield (kg/ha) weeding soil type Potential Yield Yield Gap variety lodging water stress diseases timely planting cropping system Average Yield Actual Yield Count kg / ha 0 farmers fields research station We hardly supplied hard facts as required for extension services, planners and researchers

30 We performed a desk study using technology transfer : To achieve a thorough screening of options that are not practiced in the area To identify potential development solutions that require further study of the (LUT s LU s) combinations evaluated as Suitable