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Spatial variation in costs of sustainable
land management technologies – a review


Luuk Fleskens
UNCCD 2nd Scientific Conference

Economic assessment of desertification, sustainable land
management and resilience of arid, semi-arid and dry sub-humid areas

10 April 2013, Bonn, Germany
Sustainable
Overview        land management (SLM)




                               • Often requires investment
                               • Almost always takes time to
                                 develop beneficial effects

                               • Variability in investment costs
                                matters
        www.desire-his.eu
Cost variability
Overview            effects of environmental conditions
i. Slope
      •    spacing for line interventions
      •    soil movement requirements (terraces)
      •    type of construction mechanisms
      •    loss of effective area for cultivation
ii. Soil type (texture, depth)
      •    workability (labour and machine input)
      •    stability of risers
iii. Land use
      • initial condition/local availability resources
      • severity of land degradation (temporal effect)
iv. Combinations of environmental conditions
      • interactions of e.g. slope and soil texture, or slope and
        soil depth
Cost variability
Overview           effects of location


Plot location often found to be of importance in
explaining adoption patterns of SLM technologies
i. Labour
   • manpower major component of SLM investment labour
     opportunity costs are difficult to establish (often assumed
     to be zero) but important
   • often near homesteads where high value crop production
     is concentrated and labour opportunity costs are lowest
ii. Material inputs (commodities/non-commodities)
   • Availability building materials (stones, poles) depends on
     position in landscape; due to bulky nature difficult to
     transport over long distances.
   • Many commodities to be purchased from markets;
     location affects market price and transport costs.
as follows:

Overview data for variability investment cost
Example                     (1)




    Tenge et al. 2005. Appl Geog 25: 348-365
as follows:

Overview mapping spatial variability investment cost
Example                             (1)




                  The standard cost reported for TUN11 is 50 US$
                  ha-1 for fencing. An allowance was made for
                  transport costs of fencing material (up to
                  US$3.36) and slope (up to US$3.00). The
                  resulting map of investment costs ranges from
                  US$ 50.11 (blue) – US$ 54.91 (red)




   Cost of different types
   of SLM measures (Eur/ha)
   TUN11 Rangeland resting
as follows:

Overviewassessment spatial variability investment cost
Impact                 (1)




as follows:

       𝐼𝑁𝑉𝑆 = 𝑈𝑆$1,823 ∗ 𝑆/30                                         (1
     In Yanhe river basin, China bench terraces are applicable in
     3,732 km2

     The average cost is $1,591 ± $717

     Subtracting mean from calculated cost, we can reduce spatial
     variability by multiplying by fractions 0.75, 0.5, 0.25 and 0.
as follows:


Effect of
Overview                  spatial variability of investment cost
                                           (1)

                                                                                                                                       60%




                                                                                             Financial viability (% applicable area)
 Investment cost                          Relative level of spatial cost                                                               50%


       (US$)                                       variability                                                                         40%



                                          0 0.25 0.50 0.75                 1                                                           30%


                                                                                                                                       20%
 Maximum                              1,591 2,488 3,386 4,284 5,182
                                                                                                                                       10%
 Minimum                              1,591 1,196       801      406      12
                                                                                                                                       0%
 St. deviation                            0     179     359      538     717                                                                 0    0.2         0.4                0.6         0.8   1
                                                                                                                                                 Relative level of spatial cost variability




              0 - 25
              25 - 50
                                            0 - 25
              50 - 100                                     0 - 25                0 - 25                                                                              0 - 25
                                            25 - 50
              100 - 250                                    25 - 50               25 - 50                                                                             25 - 50
                                            50 - 100
              250 - 500                                    50 - 100              50 - 100                                                                            50 - 100
                                            100 - 250
              500 - 750                                    100 - 250             100 - 250                                                                           100 - 250
                                            250 - 500
                                                           250 - 500             250 - 500                                                                           250 - 500
                                            500 - 750
                                                           500 - 750             500 - 750                                                                           500 - 750




                                                                                                                                                                                   0
                                                                                                                                                                                   0-0.2
                            0                                          0
                                                                                                                                                                                   0.2-0.5
                            0-0.2                                      0-0.2
                                                                                                                                                                                   0.5-1
                            0.2-0.5                                    0.2-0.5
                                                                                                                                                                                   1-2
                            0.5-1                                      0.5-1
                                                                                                                                                                                   2-5
                            1-2                                        1-2
                                                                                                                                                                                   5-10
                            2-5                                        2-5
                                                                                                                                                                                   10-20
                            5-10                                       5-10
                                                                                                                                                                                   20-50
                            10-20                                      10-20
                                                                                                                                                                                   > 50
                            20-50                                      20-50
                            > 50                                       > 50
Bottleneck
Overview     III: Scale and circumstances
Bottleneck
Overview     III: Scale and circumstances
Conclusions
Overview

1. Spatial variation in investment costs of SLM technologies and distance to
   markets play a key role in defining appropriate SLM strategies and
   policies. Explicit studies of variations in costs are scarce.

2. SLM projects, institutions and stakeholders at all levels could be engaged
   in better documenting the variability of investment costs of SLM
   technologies, ideally in connection with M&E of impacts.

3. Such data are invaluable for modelling approaches that are bound to
   become more important in making ex-post and ex-ante assessments of
   the viability of SLM technologies.

4. Evidence for spatial variability of investment costs will inform model
   assessments of SLM viability. Such assessments have an important role
   to play in assessing the potential for upscaling of SLM

5. Through partnerships and data-sharing multi-level impacts can best be
   achieved, and links between remote locations with similar land
   degradation concerns harnessed.
Overview




           l.fleskens@leeds.ac.uk

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Luuk FLESKENS "Spatial variation in costs of sustainable land management technologies – a review"

  • 1. Spatial variation in costs of sustainable land management technologies – a review Luuk Fleskens UNCCD 2nd Scientific Conference Economic assessment of desertification, sustainable land management and resilience of arid, semi-arid and dry sub-humid areas 10 April 2013, Bonn, Germany
  • 2. Sustainable Overview land management (SLM) • Often requires investment • Almost always takes time to develop beneficial effects • Variability in investment costs matters www.desire-his.eu
  • 3. Cost variability Overview effects of environmental conditions i. Slope • spacing for line interventions • soil movement requirements (terraces) • type of construction mechanisms • loss of effective area for cultivation ii. Soil type (texture, depth) • workability (labour and machine input) • stability of risers iii. Land use • initial condition/local availability resources • severity of land degradation (temporal effect) iv. Combinations of environmental conditions • interactions of e.g. slope and soil texture, or slope and soil depth
  • 4. Cost variability Overview effects of location Plot location often found to be of importance in explaining adoption patterns of SLM technologies i. Labour • manpower major component of SLM investment labour opportunity costs are difficult to establish (often assumed to be zero) but important • often near homesteads where high value crop production is concentrated and labour opportunity costs are lowest ii. Material inputs (commodities/non-commodities) • Availability building materials (stones, poles) depends on position in landscape; due to bulky nature difficult to transport over long distances. • Many commodities to be purchased from markets; location affects market price and transport costs.
  • 5. as follows: Overview data for variability investment cost Example (1) Tenge et al. 2005. Appl Geog 25: 348-365
  • 6. as follows: Overview mapping spatial variability investment cost Example (1) The standard cost reported for TUN11 is 50 US$ ha-1 for fencing. An allowance was made for transport costs of fencing material (up to US$3.36) and slope (up to US$3.00). The resulting map of investment costs ranges from US$ 50.11 (blue) – US$ 54.91 (red) Cost of different types of SLM measures (Eur/ha) TUN11 Rangeland resting
  • 7. as follows: Overviewassessment spatial variability investment cost Impact (1) as follows: 𝐼𝑁𝑉𝑆 = 𝑈𝑆$1,823 ∗ 𝑆/30 (1 In Yanhe river basin, China bench terraces are applicable in 3,732 km2 The average cost is $1,591 ± $717 Subtracting mean from calculated cost, we can reduce spatial variability by multiplying by fractions 0.75, 0.5, 0.25 and 0.
  • 8. as follows: Effect of Overview spatial variability of investment cost (1) 60% Financial viability (% applicable area) Investment cost Relative level of spatial cost 50% (US$) variability 40% 0 0.25 0.50 0.75 1 30% 20% Maximum 1,591 2,488 3,386 4,284 5,182 10% Minimum 1,591 1,196 801 406 12 0% St. deviation 0 179 359 538 717 0 0.2 0.4 0.6 0.8 1 Relative level of spatial cost variability 0 - 25 25 - 50 0 - 25 50 - 100 0 - 25 0 - 25 0 - 25 25 - 50 100 - 250 25 - 50 25 - 50 25 - 50 50 - 100 250 - 500 50 - 100 50 - 100 50 - 100 100 - 250 500 - 750 100 - 250 100 - 250 100 - 250 250 - 500 250 - 500 250 - 500 250 - 500 500 - 750 500 - 750 500 - 750 500 - 750 0 0-0.2 0 0 0.2-0.5 0-0.2 0-0.2 0.5-1 0.2-0.5 0.2-0.5 1-2 0.5-1 0.5-1 2-5 1-2 1-2 5-10 2-5 2-5 10-20 5-10 5-10 20-50 10-20 10-20 > 50 20-50 20-50 > 50 > 50
  • 9. Bottleneck Overview III: Scale and circumstances
  • 10. Bottleneck Overview III: Scale and circumstances
  • 11. Conclusions Overview 1. Spatial variation in investment costs of SLM technologies and distance to markets play a key role in defining appropriate SLM strategies and policies. Explicit studies of variations in costs are scarce. 2. SLM projects, institutions and stakeholders at all levels could be engaged in better documenting the variability of investment costs of SLM technologies, ideally in connection with M&E of impacts. 3. Such data are invaluable for modelling approaches that are bound to become more important in making ex-post and ex-ante assessments of the viability of SLM technologies. 4. Evidence for spatial variability of investment costs will inform model assessments of SLM viability. Such assessments have an important role to play in assessing the potential for upscaling of SLM 5. Through partnerships and data-sharing multi-level impacts can best be achieved, and links between remote locations with similar land degradation concerns harnessed.
  • 12. Overview l.fleskens@leeds.ac.uk