The document presents a numerical model for assessing social, economic, and environmental impacts of policies to combat desertification in Chile. It summarizes the development of a methodology using descriptive and predictive territorial and socioeconomic indicators to simulate future desertification under different scenarios. Regression analysis was used to relate land use and socioeconomic structure. The model shows that investments in agriculture, livestock, and forestry by government agencies contribute to reducing desertification, while overgrazing increases it. In scenarios without these investments, desertification worsens in all regions, showing the importance of promotion laws in the fight against desertification.

1. NUMERICAL MODEL FOR SOCIAL, ECONOMIC
AND ENVIRONMENTAL ASSESSMENT OF SUPPORT
MECHANISMS TO COMBAT DESERTIFICATION IN
CHILE.
PhD Carla Ximena Salinas Silva

2. INTRODUCTION

3. INTRODUCTION
THE DESERTIFICATION IN CHILE
In Chile the desertification process covers 48,334,300
hectares, which represents two thirds of the country.
Thus, it is considered the largest environmental problem,
generating a significant environmental and socioeconomic
impact which directly affects more than 1.3 million people, and
in the municipalities most severely affected, poverty reaches
60.2% of the population.
According to the latest agricultural census, the 78% of
productive land in Chile, showed degrees of erosion, ranging
from moderate to very severe (CONAF 1999), and in the
period 1997-2007, the country has lost 32% of fertile land (INE
2009).

4. INTRODUCTION
EVALUATION OF THE AGRICULTURE, LIVESTOCK AND FORESTRY
DEVELOPMENT LAWS TO COMBAT DESERTIFICATION AND DROUGHT
IN NORTHERN CHILE
The National Forestry Commission (CONAF), through its Decree
Law No. 701 on forestry development includes the reforestation of
lands for the purpose of encouraging the recovery of degraded forest
lands.
The Agriculture and Livestock Service (SAG) through Supreme
Decree No. 202 incorporates the recovery of soils in agricultural land
use through conservation, reclamation and rehabilitation.
Similarly Law No. 18,450 of the National Irrigation Commission
(CNR) aims to increase the irrigated areas of the country by
encouraging the irrigation of dry land, and incorporating new land to
farm.

5. INTRODUCTION
OBJECTIVES
• Objectives:
– Developing an evaluation methodology based on descriptive
and predictive capacity of territorial and socio-economic
indicators.
– Simulation of the state of desertification in the future, in
different economic scenarios on a model for the proposition of
possible improvements.
– Evaluation of the impact of the combat against desertification
and drought in the agriculture, livestock and forestry sector in
Chile.

6. STUDY AREA
•This work takes place in north-
central Chile, between latitudes 17º
30'S and 36º 33'S.
•The areas between these latitudes
are the administrative Regions
affected to greater erosion and
drought in the country.
•The total surface area of study is
37,935,970 ha, representing 50.2%
of the country.

7. STATE OF THE ART
SURFACE AFFECTED BY DESERTIFICATION
The regions most affected by
desertification are the IV, II, and
XV
V. This Regions have more than
50% of their territory in severe
I
conditions of desertification.
II ​
These values are opposed to the
Regions VI and VII which present
the greatest part of its territory
III
​
with values of moderate and
lighter desertification
respectively.
IV
V
XIII
VI
VII

8. MATERIAL AND METHODS
•Study indicators
•Model development

9. MATERIAL AND METHODS
STUDY INDICATORS
The selection of the territorial and socioeconomic variables was performed by
reference to the indicators recognized by the United Nations Convention to
Combat Desertification and Drought (UNCCD).
The selected territorial indicators characterized the study area from an
analytical point of view. An important criterion for the selection of these
indicators lies in the fact that they relate directly to human activities on the
territory. The descriptors that are independent of human activity were not
directly considered in this study.
The selected socioeconomic indicators were related to the production
structure of the territory under study, rates of poverty and human
development, infrastructure and investments made by agriculture, forestry and
livestock promotion institutions.

10. MATERIAL AND METHODS
STUDY INDICATORS
Socioeconomic indicators Territorial indicators
CNR's total investment in U.S. $ Surface intervened by the CNR
SAG's total investment in U.S. $ Technical irrigation surface by the CNR
CONAF´s total investment in U.S. $ New irrigation surface CNR
Total population Surface intervened by the SAG
Poor population Surface intervened by CONAF
Non-poor population Surface in severe condition of desertification
Number of vehicles Surface in moderate condition of desertification
Employed population Surface in light condition of desertification
Unemployed population Surface not affected by desertification
Number of farms Surface without information about the status of
Number of cattle heads desertification
Forest fires Surface occupied by annual crops
Overgrazing (number of goat and sheep) Surface occupied by sown pastures
Population employed in agriculture Surface occupied by fallows
Water reservoir capacity (m3) Surface occupied by improved grasslands
Surface occupied by rangeland
Surface occupied by forest plantations
Surface occupied by native forests
Surface occupied by infrastructure
Surface occupied by barren land
CNR: National Irrigation Comission CONAF: Forest Service SAG: Livestock & Forest Service

11. MATERIAL AND METHODS: APPLIED MODEL DEVELOPMENT
The data were homogenized in relation to the TERRITORIAL SOCIOECONOMIC
​
total surface of the region to which they INDICATORS INDICATORS
belonged, and then were subjected to logarithmic
transformation (log (α +1)).
In order to determine the main territorial a)
Y
components of the desertification a PCA to the
territorial variables and an ordination of the X
regions in two axes (x, y) were carried out.
A relationship between the type of land and the
socioeconomic structure in the study area is
established using multiple regression analysis.
Independent variables were socioeconomic b) Y = a + b·X 1 + b 2·X 2 +b 3·X3 +……+b n ·Xn
descriptors and the dependent variables
corresponded to the territorial variables.
This equation was used to simulate a scenario XV
extrapolating a situation to help reversing the
VII
VI
desertification process and another scenario
V
IV
extrapolating a “no action " situation in which
III
c) II
there were no bonuses given by the ALF
I
0,0 0,1 0,1 0,2 0,2 0,3 0,3 0,4
promotion agencies.

12. RESULTS AND DISCUSSION
• Applied model development

13. RESULTS AND DISCUSSION
ASSESSMENT OF THE SOCIO-ECONOMIC AND
TERRITORIAL STRUCTURE INVOLVED IN
DESERTIFICATION PROCESSES
SUMMARY OF THE MODEL: it can be used as a
methodology for the evaluation of development policies in
the fight against desertification and drought.

14. RESULTS AND DISCUSSION
ASSESSMENT OF THE SOCIO-ECONOMIC AND TERRITORIAL
STRUCTURE INVOLVED IN DESERTIFICATION PROCESSES
Desertification gradient obtained from the PCA for the Component 1.
Component 1 (62,03 % of the variance)
Negative end - Positive end +
Severe desertification (-0,55) New irrigation surface CNR (0,99)
Moderate desertification (-0,42) Technical irrigation surface by the CNR (0,98)
Surface occupied by improved grasslands (0,93)
Surface occupied by annual crops (0,93)
Surface occupied by forest plantations (0,92)
Surface intervened by the SAG (0,92)
Surface occupied by native forests (0,90)
Surface intervened by CONAF (0,90)
Surface intervened by the CNR (0,864)
Surface occupied by sown pastures (0,864)
The gradient indicates the importance of the three development agencies,
CONAF, SAG and CNR, in the fight against desertification and drought.

15. RESULTS AND DISCUSSION
ASSESSMENT OF THE SOCIO-ECONOMIC AND TERRITORIAL
STRUCTURE INVOLVED IN DESERTIFICATION PROCESSES
Relation between desertification and the socioeconomic indicators
Desertification = 0.269 – 0.021 CONAF´s subsidies - 0.08 CNR´s
subsidies – 0.632 SAG´s subsidies + 1.331 Total population – 0.218
Number of farms +3.386 Grazing – 0.008 water reservoir capacity

16. RESULTS AND DISCUSSION
ASSESSMENT OF THE SOCIO-ECONOMIC AND TERRITORIAL STRUCTURE
INVOLVED IN DESERTIFICATION PROCESSES
Simulation 1. Baseline and ACTION simulation
XV
VII
VI
REGIONS
V
IV
III
II
I
-0,3 -0,2 -0,1 0,0 0,1 0,2 0,3 0,4
DESERTIFICATION
BASELINE ACTION SIMULATION
ACCION INSTITUCUINES DE FOMENTO
CNR INVEST. SAG INVEST. TOTAL RESERVOIR
REGION CONAF INV. US$ FARM SURFACE GRAZING
US$ US$ POPULATION CAPACITY
I 25% 25% 25% 20% 1,10% 25% -50%
II 25% 25% 25% 20% 1,10% 25% -50%
III 50% 50% 50% 20% 1,10% 25% -50%
IV 50% 50% 50% 20% 1,10% 50% -50%
V 50% 50% 50% 20% 1,10% 25% -50%
VI 15% 15% 15% 20% 1,10% 25% -50%
VII 15% 15% 15% 20% 1,10% 25% -50%
XV 25% 50% 0% 20% 1,10% 25% -50%

17. RESULTS AND DISCUSSION
ASSESSMENT OF THE SOCIO-ECONOMIC AND TERRITORIAL STRUCTURE
INVOLVED IN DESERTIFICATION PROCESSES
Simulation 2. Baseline and NO ACTION simulation
XV
VII
VI
REGIONS
V
IV
III
II
I
-0,2 -0,1 0,0 0,1 0,2 0,3 0,4 0,5 0,6 0,7
DESERTIFICATION
BASELINE NO ACTION SIMULATION
NO ACCION INSTITUCUINES DE FOMENTO
CNR INVEST. SAG INVEST. TOTAL RESERVOIR
REGION CONAF INV. US$ FARM SURFACE GRAZING
US$ US$ POPULATION CAPACITY
I 0% 0% 0% 20% 1,10% 25% -50%
II 0% 0% 0% 20% 1,10% 25% -50%
III 0% 0% 0% 20% 1,10% 25% -50%
IV 0% 0% 0% 20% 1,10% 50% -50%
V 0% 0% 0% 20% 1,10% 25% -50%
VI 0% 0% 0% 20% 1,10% 25% -50%
VII 0% 0% 0% 20% 1,10% 25% -50%
XV 0% 0% 0% 20% 1,10% 25% -50%

18. CONCLUSIONS

19. CONCLUSIONS
• The mitigation strategies in the fight against desertification and
drought in Chile are effective and the effectiveness varies by region.
• The model shows that both the money invested by CONAF, SAG
and CNR and the surface intervened by these institutions contribute
to combat desertification and drought in Chile.

20. CONCLUSIONS
• The result indicates that the overgrazing is a major cause of
desertification in the regions studied. Desertification due to
overgrazing is also documented for other areas of the world.
• In the absence of subsidies, desertification increase in all regions,
even in regions VI and VII, where climatic conditions are more
favorable. This indicates the importance of Agriculture, Livestock
and Forestry propmotion laws in the fight against desertification.
• The model result also shows the reservoirs and successful agent in
the fight against desertification and drought, as well as farms.

21. CONCLUSIONS
In areas affected by desertification and drought than
usual is that ecosystems are not given enough water or
funding. From an economic point of view, this situation
leads to inadequate assessment of environmental goods
and services that provide the drylands, which results on
immediate misuse. That is, over use capacity, especially
because of the overexplotation of resources in arid,
semiarid and dry sub-humid land. Therefore, sustainable
development in desertified areas is to promote
innovative schemes of economic production with
environmental and social sound basis.

22. THANK YOU VERY MUCH
MUCHAS GRACIAS