Socioeconomic development and vulnerability to land degradation in Italy
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Transcript of Socioeconomic development and vulnerability to land degradation in Italy
ORIGINAL ARTICLE
Socioeconomic development and vulnerability to land degradationin Italy
Luca Salvati • Alberto Mancini • Sofia Bajocco •
Roberta Gemmiti • Margherita Carlucci
Received: 22 August 2010 / Accepted: 25 February 2011 / Published online: 22 March 2011
� Springer-Verlag 2011
Abstract In recent years, the surface area affected by
land degradation (LD) has significantly increased in
southern European regions where the socioeconomic
development has been proposed as a basic factor underly-
ing the degree of vulnerability to LD. This paper investi-
gates the correlation between several socioeconomic
indicators and the level of vulnerability to LD in Italy,
expressed as changes (1990–2000) in a composite index of
land vulnerability (DLVI). The analysis was carried out
over 784 local districts. The impact of per capita value
added, agricultural intensity, industrial and tourism con-
centration, and urban growth was separately tested on
DLVI. Results indicate that a lower district value added,
crop intensification, irrigation, and the level of land vul-
nerability to degradation are strongly associated with the
increasing level of land vulnerability over time, highlight-
ing the role of the socioeconomic development as a main
process underlying LD. In this framework, spatially equi-
table sustainable development may represent the effective
strategy to mitigate the detrimental effects of economic
growth and regional disparities on Mediterranean LD.
Keywords Land degradation � Vulnerability �Socioeconomic indicators � Sustainable development �Local district � Mediterranean region
Introduction
Land degradation (LD) is defined as a long-term decline in
ecosystem function and productivity and is worldwide
recognized as an important issue in the political agenda for
the 21st century (Stringer 2008). The LD process appears
particularly severe in developing countries (Africa, south-
ern Asia, and Latin America); however, because of climate
change and growing human pressure, it is becoming critical
also in many developed countries, such as United States,
Australia, and some parts of the Mediterranean basin
(Rubio et al. 2009).
Mediterranean LD is a multifaceted and dynamic pro-
cess depending on biophysical, socioeconomic, cultural,
and institutional factors, with strong negative effects on
food security and quality of life (Conacher and Sala 1998;
Conacher 2000). Due to this complexity, LD was often
approached at ‘on-site’ scale with a focus on the bio-
physical causes (Puigdefabregas and Mendizabal 1998;
Geist and Lambin 2004; Montanarella 2007). To the
L. Salvati
Italian Council of Agricultural Research, Research Centre for
Plant-Soil Systems, Via della Navicella 2-4, 00185 Rome, Italy
A. Mancini (&)
c/o Centre for Economic and International Studies—CEIS,
‘Tor Vergata’ University of Rome, Via Columbia, 2,
00133 Rome, Italy
e-mail: [email protected]
S. Bajocco
Italian Council of Agricultural Research, Research Unit of
Climatology and Meteorology Applied to Agriculture,
Via del Caravita 7a, 00186 Rome, Italy
R. Gemmiti
Department of Geographical, Linguistic, Statistical,
Historical Studies for Regional Analysis, Faculty of Economics,
‘Sapienza’ University of Rome, Via del Castro Laurenziano 9,
00161 Rome, Italy
M. Carlucci
Department of Economics, Faculty of Statistics,
‘Sapienza’ University of Rome, Piazzale A. Moro 5,
00185 Rome, Italy
e-mail: [email protected]
123
Reg Environ Change (2011) 11:767–777
DOI 10.1007/s10113-011-0209-x
contrary, relatively few studies have dealt with the phe-
nomenon at regional scale, analyzing the interaction
between human factors and the ecological variables
(Briassoulis 2004). Moreover, LD is a dynamic attribute of
the territory mainly depending on its biophysical charac-
teristics (climate, soil, vegetation) and possibly changing
over time (Basso et al. 2000; Lavado Contador et al. 2009).
Understanding the spatiotemporal trends (rather than the
present status) of LD may allow to identify and foresee the
spatial distribution of vulnerable areas (Salvati and Ba-
jocco 2011), hence representing a key issue both from the
ecological and from policy points of view.
When dealing with LD, monitoring strategies should be
the major concern and they should encompass the multidis-
ciplinary perspectives of the problem (Reynolds and Stafford
Smith 2002; Gisladottir and Stocking 2005). Accordingly, a
number of recent studies have been carried out and different
methodologies to study LD have been proposed: visual
observation, field measurements, social enquiries, environ-
mental indicators derived from statistical sources, remote
sensing, and mathematical models (Basso et al. 2000; Bath-
urst et al. 2003; Salvati and Zitti 2009). With respect to other
approaches, environmental indicators have the advantage of
(1) producing synthetic information on the spatiotemporal
dynamics of multivariate phenomena, (2) being reasonably
comparable among different countries, and (3) being easily
communicable to both stakeholders and policy-makers.
In this perspective, the aim of this paper was to contribute
to the knowledge of LD through an exploratory analysis of
the relationship between changes in land vulnerability over
time and several socioeconomic underlying factors. The
analysis was carried out in Italy, a southern European
country with different levels of land vulnerability and
marked socioeconomic disparities (Salvati and Zitti 2009).
Materials and methods
Study area
The study area (Italy, ca. 301.330 km2) is divided into 784
districts (Local Labor Market Districts, LLMAs) identified
on the basis of data related to daily labor mobility (ISTAT
1997). LLMAs reflect districts of socioeconomic interest
and are used to analyze the regional development of Italy
(Pellegrini 2002), the local specialization in agriculture
(Giusti and Grassini 2007), and the level of land vulnera-
bility to degradation (Salvati and Zitti 2009).
The distribution of district income in term of per capita
gross value added was mapped in Fig. 1. In 2000, northern
Italy resulted as one of the most developed European
regions, while southern Italy was still an economically
disadvantaged area, with per capita value added about half
of that observed in northern Italy (ISTAT 2006). In
southern Italy, only few districts, featuring industrial con-
centration and high-yield agriculture, showed the levels of
per capita value added greater than 10,000 euros, which
was much lower than the Italian average (14,300 euros).
The land vulnerability index
LD is related, on one hand, to the environmental man-
agement due to human activities and, on the other hand, to
the endowments of land resources that are mostly due to
the geographical location and the biophysical context. The
separate effects of these two components (i.e., land
resources ‘‘management’’ and ‘‘endowments’’) can be
quantified by analyzing the LD changes of a territory over
time rather than its (static) present status, inferring about
the behind processes (Salvati and Zitti 2009).
Based on these considerations, we computed a composite
index estimating changes in the level of land vulnerability
through time in Italy. While the most used LD indexes are
set up by following the Environmental Sensitive Area
(ESA) procedure (Basso et al. 2000; Lavado Contador et al.
2009; Salvati and Bajocco 2011), we used an ESA-like
index of vulnerability to LD (the so-called LVI), which is
better suited to account for some peculiar characteristics of
the Italian landscape and circumvents data limitations at
high-resolution scales (Salvati and Zitti 2008; Salvati et al.
2009). The LVI is composed of three thematic indicators of
climate, soil properties, and vegetation quality, which pro-
duce a ranking of biophysical vulnerability to LD.
Climate variables include the aridity index, the average
annual rainfall, the rainfall variability, and concentration,
as well as the average number of rainy days (all measured
over a 30-year period). Soil variables include the soil depth
and texture, the potential available water capacity, the
organic carbon content, and a proxy for soil erosion risk.
Finally, vegetation variable, derived from land cover,
include sensitivity to drought, fire risk, protection from soil
erosion, and land cover intensity.
The LVI was tested in several field sites in order to
check the relationship between the index scores and several
independent measures of soil and land degradation (Salvati
et al. 2009).
We estimated the LVI for 2 years (1990 and 2000) on a
district basis over the whole Italy; the spatial distribution of
LVI in 2000 was mapped in Fig. 1. We used the difference
in the LVI among the two periods (DLVI) by local district
as the dependent variable in the regression model.
Socioeconomic data and indicators
There is no consensus about the type and number of factors
possibly associated with LD in the Mediterranean region
768 L. Salvati et al.
123
(Mairota et al. 1998). The choice usually depends on data
availability and research objectives. From the economic
point of view, the possible determinants of LD should
cover social, production, policy, and sociodemographic
factors, as well as site-specific variables (Briassoulis 2004).
Wilson and Juntti (2005) introduced various hypotheses to
explain Mediterranean LD, including (1) the ‘‘human
pressure’’ hypothesis, (2) the ‘‘agricultural impact’’
hypothesis, and (3) the ‘‘environmental factors’’ hypothe-
sis. Concerning Italy, the empirical analysis provided by
Salvati and Zitti (2008) corroborates Wilson and Juntti
(2005) approach, suggesting that crop intensification, urban
sprawl, industrial concentration, and tourism pressure
represent potentially important factors affecting LD at
regional scale.
Several variables were selected as predictors in the
regression model and classified into different groups
according to their potential link to land vulnerability
dynamics. Three classes of covariates measured at the
district level were identified, namely (1) socioeconomic
variables, (2) agricultural variables, and (3) environmental
or control variables (Table 1). We chose candidate vari-
ables according to the results illustrated in previous works
(Montanarella 2007; Rubio et al. 2009; Tanrivermis 2003).
The ‘‘socioeconomic’’ covariates (SOC) included seven
variables: per capita gross value added (GVA), the share of
agriculture (AGP) and industry (IND) in total product, land
productivity (LAN), labor productivity in services (SER), as
well as two dummies, respectively, identifying urban dis-
tricts (URB), and tourism-specialized districts (TOU) (these
two variables were fully described in ISTAT 2006). It is
important to note that the term ‘local income’ is used in
this paper as synonym of district value added and does not
directly refer to the average income of private households
within the investigated area.
The ‘‘agricultural’’ covariates (AGR) included five
variables: the percentage of agricultural land on the total
district area indicating the local specialization in agricul-
ture (AUA), the variation of agricultural land surface over a
10-year horizon (1990–2000) indicating potential processes
of land abandonment (LOS), the percentage of irrigated
agricultural land (IRR), the percentage of economically
marginal farms (i.e., Agricultural Utilized Area \ 2 hect-
ares, MAR), and an index of crop intensity describing
potential processes of agricultural intensification (INT).
The ‘‘environmental’’ and control covariates (ENV)
included five variables: the LVI score measured at the
beginning of the study period (LVI), the average district’s
elevation (ELE), surface area (SUR), and population den-
sity (POP), as well as a dummy for the geographical area
(northern ? central Italy districts = 0, southern Italy ?
the two main islands districts = 1; GEO). The classifica-
tion of the Italian territory in two areas (north ? centre,
south ? Islands) follows an economic rationale related to
the EU’s funding strategy. For a long term, EU structural
funds subdivided Italy into eight economically disadvan-
taged target regions (all belonging to southern Italy) and
twelve developed regions (all belonging to central and
northern Italy). This classification reflects the different
environmental conditions occurring in the two analyzed
areas (Salvati and Zitti 2009). All variables were calculated
at the district scale from national accounts and census data
provided by the Italian National Institute of Statistics
(ISTAT 2006) and refer to the years 2000 or 2001 when not
differently specified.
Statistical analyses
In order to avoid redundancy and collinearity among vari-
ables, we carried out a preliminary analysis on the selected
Fig. 1 Left district value added (GVA) across Italy (expressed in Euros per capita). Middle land vulnerability to degradation (LVI) in Italy (both
variables refer to 2000). Right changes in land vulnerability in 1990–2000 (DLVI)
Socioeconomic development and vulnerability 769
123
covariates. We computed a correlation matrix among pre-
dictors (using the Pearson moment coefficient and the
Spearman rank correlation coefficient) and preliminary
stepwise Ordinary least square (OLS) regressions among the
dependent variable and the three classes of predictors (SOC,
AGR, ENV) alone and pooled together. Four variables (AGP,
AUA, MAR, SER) were then excluded from the analysis due
to their strong correlation (|r| [ 0.5) with the other covariates
(i.e., AGP and SER vs. GVA, AUA vs. INT, MAR vs. IRR).
The environment–development nexus was explored, at
the first stage, through regressions between the changes in
the land vulnerability index (DLVI) and per capita value
added alone based on different specifications (e.g., linear,
quadratic, cubic equations). A widely used way to specify
the development–environment relationship is to adopt first-,
second-, and third-order polynomials, comparing different
specifications for relative robustness (Mukherjee and
Kathuria 2006). In this paper, the best form (in terms of
goodness-of-fit) was chosen by using standard diagnostics.
The framework was then enlarged by incorporating addi-
tional socioeconomic variables to the above-mentioned
specification and by checking for spatial effects. Results
were finally analyzed by comparing the coefficient estimates
obtained through the different specifications.
Table 1 Average (and standard error) values of the considered variables across Italy
Variable (acronym) Average (±SE) Source
Number of districts 784 ISTAT (1997)
Change in land vulnerability over time (DLVI, %) 11.7 (0.1) This paper
Socioeconomic variables (SOC)
District value added (GVA, euros per capita) 14,300 (215) ISTAT (2006)a
Share of industry in total product (IND, %) 26.9 (0.4) ISTAT (2006)a
Share of agriculture in total product (AGP, %)* 8.1 (0.2) ISTAT (2006)a
Tourism districts (TOU) 9.1 g ISTAT (2006)b
Urban districts (URB) 4.9 g ISTAT (2006)b
Land productivity (LAN, euros per hectare of AUA) 1,900 (29) ISTAT (2006)c
Labor productivity of service (SER, euros per worker)* 46,666 (645) ISTAT (2006)a
Agricultural variables (AGR)
Crop intensity (INT) 0.68 (0.01)h ISTAT (2006)d
Agricultural utilized area (AUA, %)* 44.1 (0.7) ISTAT (2006)d
Change in agricultural surface (LOS, %) 90.4 (0.7) ISTAT (2006)d
Irrigated land (IRR, %) 14.7 (0.7) ISTAT (2006)d
Economically marginal farms (MAR, %)* 13.7 (0.5) ISTAT (2006)d
Environmental and control variables (ENV)
Land Vulnerability Index in 1990 (LVI) 0.39(0.002)i This paper
District elevation (ELE) 40.6 l ISTAT (2006)e
Average district surface (SUR, km2) 384.3 (13) ISTAT (1997)
Population density (POP, inhabitants km-2) 183.2 (10) ISTAT (2006)f
Geographical area (GEO) 46.6 m ISTAT (1997)
* Variables excluded from the regression analysis due to their collinearitya National accountsb Elaborations from ISTAT (1997)c National Accounts and Census of Agricultured Census of Agriculturee Our elaborations based on a 250 m digital elevation model provided courtesy of L. Perini (CRA-CMA, Rome) and integrated with data from
ISTAT (2006)f Census of Population and Householdsg Percentage of tourism and urban districts on the total number of districts in that areah INT Ranges from 0 to 1; higher values indicate increasing crop intensityi LVI Ranges from 0 to 1; higher values indicate increasing vulnerability to LDm Percentage of southern districts on total Italian districts. All variables refer to 2000l Percentage of mountain districts (with average ELE [ 650 m)
770 L. Salvati et al.
123
In detail, the regression analysis estimated a vector of
coefficients, each linked to a single, potential driver of the
specified environmental process, by using the reduced form
E = f (Y, A), where E represents the environmental process
under study, Y is the income variable, and A is a set of
additional variables describing the level of socioeconomic
development. When it is significant, the relation may be linear
or polynomial. In the former case, it was supposed that
socioeconomic development is (positively or negatively)
associated with changes in land vulnerability to degradation
over the entire range of observed income. In the latter case,
development is correlated with decreasing levels of land
vulnerability at lower (or intermediate) levels of district
income, whereas a ‘re-linking’ process (i.e., increasing LD
vulnerability) is expected at higher income. More complex
patterns (e.g., third-order polynomials) may highlight site-
specific responses of land vulnerability to socioeconomic
development. The multidimensionality of this concept
reflects the different behavior of the additional socioeconomic
variables compared with that of income (Galeotti 2007).
The relationship between the DLVI and the socioeco-
nomic features of each district was thus tested here by
specifying different forms starting with the simplest one,
relating DLVI and (district) per capita value added (in
absolute and logarithm numbers) alone (GVA) or with the
vector Xi, which includes the additional covariates. At the
first stage, the following equation was estimated:
DLVI ¼ b0 þ b1ðGVAÞ þ b2ðGVAÞ2 þ b3ðGVAÞ3 þ e ð1Þ
where b0 is the intercept and b(d) are the coefficient terms.
The vector Xi that includes the three classes of (additional)
variables (SOC, AGR, and ENV) was then incorporated in
the selected form as follows:
DLVI ¼ b0 þ b1 GVAð Þ þ b2 GVAð Þ2
þ b3 GVAð Þ3þbm Xið Þ þ e ð2Þ
Equations 1–2 were first estimated through OLS
regression. Collinearity among variables was checked
throughout by using the variance inflation factor and
condition index. Outputs report the variables in each model
with significant coefficients and standard errors. Notably,
OLS regression assumes spatial randomness, which
indicates that any grouping of high or low values of the
study variable in space would be independent. If this
assumption is not true, i.e., a spatial structure exists in the
variable as detected by the presence of spatial correlation,
standard OLS estimates are inefficient. We therefore
studied the spatial variation of both the dependent
variable (DLVI) and the main predictor (GVA) through
exploratory spatial data analysis techniques.
Central to this framework is the choice of the matrix that
describes the interaction structure of the cross-section
units, i.e., the definition of proximity. For each spatial unit,
a relevant neighboring set must be defined consisting of
those units that potentially interact with it. Although in
regional data analysis proximity is usually defined in terms
of contiguity, if the basic units are defined by administra-
tive boundaries, this definition may not be appropriate. We
hence used an alternative approach, i.e., a spatial weight
matrix based on Euclidean distances between the gravita-
tional centers of the local districts. As regards the spatial
distribution of DLVI in Italy, potential interactions between
locations were summarized by the matrix W = {wij},
where wij = 1 if districts i and j are within a fixed distance,
d, of each other and 0 otherwise. We considered eight
values of d ranging from 25 to 200 km with a span of
25 km in order to assess how far the links between spatial
units extend, i.e., the degree of spatial correlation (Anselin
2001). In this way, the analysis of spatial dependence
exhibited by given variables (i.e., DLVI and GVA) using
alternative definitions of neighborhoods (i.e., varying the
d distance) conveys information about the spatial config-
uration that maximizes the intensity of interactions
between districts.
We carried out the assessment of global spatial auto-
correlation through Moran’s I and Geary’s c statistics (Cliff
and Ord 1981). Unfortunately, Moran’s I and Geary’s
c tests provide only a general measure of spatial correla-
tion. To model the spatial correlation in association with
the explanatory variables, two approaches were developed
in this study.
The first approach is based on the spatial regression
model:
Zi ¼ li þ d; ð3Þ
where Zi is the random process at location i (i.e., DLVI), li
is the mean at the same site, which is a linear, square, or
cubic model with (1) GVA alone (i.e., the restricted model),
and (2) all the covariates (i.e., the full model), d–N(0, R)
and R is the covariance matrix of random variables at all
locations. The small-scale variation was modeled by fitting
two different covariance models to R, including conditional
spatial autoregression (CAR) and moving average (MA)
structures. The spatial weight matrix introduced in these
models was chosen according to the results of Moran’s and
Geary’s statistics.
The second approach uses the geographically weighted
regression (GWR) proposed by Fotheringham et al. (2002).
The methodological framework underlying GWR is quite
similar to that of local linear regression models, as it uses a
kernel function to calculate weights for the estimation of
local weighted regression models. Contrary to the standard
regression model, where the regression coefficients are
location invariant, the specification of a basic GWR model
for each location s = 1, …, n, is:
Socioeconomic development and vulnerability 771
123
yðsÞ ¼ XðsÞbðsÞ þ eðsÞ; ð4Þ
where y(s) is the dependent variable at location s, X(s) is
the row vector of explanatory variables at location s, b(s) is
the column vector of regression coefficients at location s,
and e(s) is the random error at location s. Hence, regression
parameters, estimated at each location by weighted least
squares, vary in space, implying that each coefficient in the
model is a function of s, a point within the geographical
space of the study area. As a result, GWR gives rise to a
distribution of local estimated parameters. The weighting
scheme is expressed as a kernel function that places more
weight on the observations closer to the location s. In this
study, we adopted one of the most commonly used speci-
fications of the kernel function, which is the bi-square
nearest neighbor function.
Finally, based on the linear form: DLVI = b0 ?
b1(GVA), the elasticity of DLVI to GVA (gld/gva) was
computed as
gld=gva ¼dðDLVIÞ
dGVADLVIGVA
¼ b1
b0 þ b1GVAð5Þ
and calculated at a defined income, which coincides with
the average per capita value added (14,300 euros). Income
figures were computed as per capita, logarithmic values
and refer to 2000.
Results
The analysis developed in this paper led to various results:
(1) changes in the level of land vulnerability to degradation
(DLVI) and district per capita value added (GVA), taken as
the key investigated variables, are both spatially depen-
dent; (2) the relationship between these two variables is
linear and negative; (3) the probability to observe
increasing levels of land vulnerability to degradation dur-
ing the investigated period (1990–2000) is higher in low-
income districts where the primary sector contributes more
to the local value added; (4) other socioeconomic variables
(crop intensity, irrigation, and the level of land vulnera-
bility measured at the initial time of study) significantly
contribute to this relationship; (v) spatial effects share a
significant contributing role to the relation itself; (vi) the
results of the regression analysis are model insensitive.
Spatial dependence of DLVI and GVA
Moran’s I and Geary’s c statistics for DLVI and GVA are
reported in Table 2. These tests confirm the positive spatial
autocorrelation across local districts for both variables:
areas with relatively high (low) DLVI (or GVA) are located
close to each other more often than if they were randomly
distributed, and the strongest spatial linkages can be found
Table 2 Measures of global spatial autocorrelation, DLVI and GVA; spatial weight matrix: geodesic distance \ d km
Moran global DLVI GVA
d I z(I) p1 p2 I z(I) p1 p2
25 0.6155 24.40 \0.001 \0.001 0.7626 30.22 \0.001 \0.001
50 0.5131 41.01 \0.001 \0.001 0.7109 56.77 \0.001 \0.001
75 0.4554 52.66 \0.001 \0.001 0.6794 78.48 \0.001 \0.001
100 0.4224 63.02 \0.001 \0.001 0.6588 98.17 \0.001 \0.001
125 0.4048 73.19 \0.001 \0.001 0.6452 116.50 \0.001 \0.001
150 0.3870 81.87 \0.001 \0.001 0.6244 131.90 \0.001 \0.001
175 0.3723 89.76 \0.001 \0.001 0.6032 145.20 \0.001 \0.001
200 0.3624 97.99 \0.001 \0.001 0.5926 160.00 \0.001 \0.001
Geary global c
d c Z(c) p1 p2 c Z(c) p1 p2
25 0.3737 -15.71 \0.001 \0.001 0.3571 -16.13 \0.001 \0.001
50 0.4608 -21.90 \0.001 \0.001 0.3642 -30.93 \0.001 \0.001
75 0.5214 -23.17 \0.001 \0.001 0.3745 -30.29 \0.001 \0.001
100 0.5616 -23.37 \0.001 \0.001 0.3797 -33.07 \0.001 \0.001
125 0.5867 -23.30 \0.001 \0.001 0.3854 -34.65 \0.001 \0.001
150 0.6060 -22.08 \0.001 \0.001 0.3909 -44.80 \0.001 \0.001
175 0.6222 -22.06 \0.001 \0.001 0.3990 -35.09 \0.001 \0.001
200 0.6338 -21.26 \0.001 \0.001 0.4049 -34.56 \0.001 \0.001
772 L. Salvati et al.
123
when ‘close’ areas are considered. Both statistics are highly
significant at all considered distances (see p levels in
Table 2).
The relationship between increasing land vulnerability
and socioeconomic variables
The relationship between DLVI and the socioeconomic
variables was explored by using different specifications
(Table 3). Based on both GVA and log-GVA, squared and
third-order polynomial regressions between DLVI and
GVA gave a goodness of fit similar (or lower) to the linear
form. Lower values of GVA are associated with increasing
levels of land vulnerability (b1 = -0.038).
The linear form incorporating spatial effects gave better
results than squared and third-order (not shown) forms
(Table 4). Lower values of GVA are linearly associated
with higher DLVI with b1 = -0.038 (CAR model) or
b1 = -0.023 (MA model).
GWR provided similar results indicating that DLVI is
linearly associated with GVA with b1 = -0.037. The
elasticity of DLVI to GVA is rather stable through the
various specifications considered: gld/gva amounted to
-0.88, -0.90, and -0.86 by considering standard OLS,
CAR, and GWR models, respectively. Estimates for Eq. 2
are presented in Table 5. An inverse, linear relationship
between GVA and DLVI is observed in all models.
As expected, high-income districts experienced lower
growth rates of DLVI irrespective of any other considered
variable: coefficients for GVA are stable in all considered
models (-0.023). DLVI resulted positively correlated with
INT, IRR, and GEO and negatively correlated with LVI.
LAN, ELE, and POP resulted (weakly) significantly cor-
related with DLVI (with negative coefficients) in MA and
GWR models only. Since second- and third-order polyno-
mial forms showed, in all considered specifications, a
goodness of fit systematically lower than the linear model,
they are neither reported in tables nor discussed in the main
text.
A socioeconomic profile of the vulnerable land
to degradation
In Italy, high vulnerable lands are mainly concentrated in
three areas: (1) the two major islands (Sicily and
Sardinia), Apulia and Basilicata, all located in southern
Italy, (2) a few dry, coastal areas close to Rome and
some located along the Adriatic Sea in central Italy and,
finally, (3) the lowland close to the Po river in north-
eastern Italy.
Table 3 Results of the standard OLS regression analysis among changes in vulnerability to LD (DLVI) and (district) per capita value added
(GVA) in Italy (standard errors of the estimates are reported in brackets)
Linear Quadratic Cubic
b0 0.201 (0.009)*** 0.104 (0.185)ns 0.104 (0.186)ns
GVA -0.038 (0.002)*** 0.010 (0.090)ns 0.010 (0.091)ns
GVA2 -0.006 (0.011)ns -0.006 (0.012)ns
GVA3 *0.000 ns
Adj-R2 0.263 0.262 0.261
F 278.0*** 139.0* 139.0*
df 1, 778 2, 777 2, 777
Stars indicate the probability level of t test associated with each regression coefficient as follows: ns p [ 0.05, * 0.01 \ p \ 0.05,
** 0.01 \ p 0.001, *** p \ 0.001
Table 4 Results of spatial regression (both conditional autoregres-
sive model, CAR, and moving average model, MA: spatial weight
matrix: d = 50 km) and geographically weighted regression (GWR)
analyses among changes in vulnerability to LD (DLVI) and per capita
value added (GVA) in Italy (standard errors of the estimates are
reported in brackets)
CAR spatial regression MA spatial regression GWR
Linear Quadratic Linear Quadratic Linear Quadratic
b0 0.200 (0.009)** 0.108 (0.185) 0.141 (0.011)** 0.230 (0.164) 0.197 (0.010)** 0.118 (0.161)
GVA -0.038 (0.002)** 0.008 (0.091) -0.023 (0.003)** -0.067 (0.080) -0.037 (0.002)** 0.002 (0.079)
GVA2 – -0.006 (0.011) – 0.005 (0.010) – -0.005 (0.010)
Adj-R2 – – – – 0.241 0.240
Log-L 824.8 824.9 935.8 935.9 – –
Stars indicate the probability level of t test associated with each regression coefficient as follows: * 0.001 \ p \ 0.05, ** p \ 0.001
Socioeconomic development and vulnerability 773
123
According to the results, four socioeconomic profiles
of the (changing) lands vulnerable to degradation in Italy
are proposed (Table 6), with different degrees of LD risk
depending on both the level of land vulnerability (low or
high) and its recent trend (increasing or decreasing):
districts classified at low risk of LD show high per capita
value added, a service-oriented economy, and low agro-
environmental pressures, and they are generally located in
northern and central Italy. To the contrary, districts
classified at moderate or high risk of LD are character-
ized by a lower level of per capita income, a more
important role of agriculture in the local economy, and a
higher level of agro-environmental pressure; they are
mainly located in coastal and upland areas in southern
Italy and, at a lesser extent, in restricted lowlands in
northern Italy.
Table 5 Results of regression analysis among changes in vulnerability to LD (DLVI), (district) per capita value added (GVA), and additional
variables in Italy (N = 784; standard errors of the estimates are reported in brackets)
OLS CAR MA GWR
b0 0.186 (0.016)** 0.181 (0.016)** 0.146 (0.015)** 0.141 (0.017)**
GVA -0.023 (0.004)** -0.023 (0.004)** -0.023 (0.004)** -0.023 (0.004)**
GEO 0.011 (0.001)** 0.011 (0.001)** 0.015 (0.002)** 0.006 (0.001)**
LVI -0.084 (0.009)** -0.082 (0.009)** -0.097 (0.013)** -0.083 (0.009)**
INT 0.011 (0.002)** 0.010 (0.002)** 0.010 (0.002)** 0.004 (0.002)*
IRR 0.009 (0.003)** 0.009 (0.003)* 0.014 (0.003)** 0.006 (0.002)*
LAN -0.006 (0.002)* -0.006 (0.002)* -0.002 (0.002) -0.001 (0.002)
ELE -0.003 (0.001)* -0.003 (0.001)* -0.001 (0.001) -0.000 (0.001)
POP -0.004 (0.002) -0.004 (0.002) -0.007 (0.002)* -0.004 (0.002)*
SUP 0.002 (0.001) 0.003 (0.001) 0.002 (0.001) 0.002 (0.001)
IND -0.010 (0.004) -0.010 (0.004) -0.012 (0.004) -0.007 (0.005)
URB -0.000 (0.002) -0.000 (0.002) -0.000 (0.002) -0.002 (0.002)
TUR -0.004 (0.002) -0.003 (0.002) -0.001 (0.001) -0.002 (0.002)
LOS -0.003 (0.002) -0.003 (0.002) -0.003 (0.002) -0.000 (0.002)
Adj-R2 0.377 – – 0.278
Log-L – 889.2 1007.0 –
Results of the full model expressed in linear terms are reported; OLS means standard a-spatial regression, CAR indicates conditional autore-
gressive spatial regression model, MA means moving average spatial regression model, and GWR indicates geographically weighted regression
model (see text for specification and technical details). Stars indicate the probability level of t test associated with each regression coefficient as
follows: * 0.001 \ p \ 0.05, ** p \ 0.001
Table 6 Socioeconomic profiles of vulnerable lands in Italy
Level of land vulnerability Low High or intermediate Low or intermediate High
Trend in land vulnerability Negative or stable Relatively stable Strongly positive Moderately positive
Geographical location Mainly in northern and
central Italy
Mainly in southern
Italy
Both in northern and
in southern Italy
Mainly in southern Italy
Elevation Mainly uplands Coastal and upland
areas
Lowlands in northern Italy;
coastal
and upland areas
in southern Italy
Both lowlands and mountain
areas
Income High Intermediate Low Low
Agro-environmental
pressure
Low Intermediate High High or intermediate
Agricultural profitability High or intermediate Low Decreasing Low
Economic structure Service-oriented and
high-quality
agriculture
Mixed Industry- and
service-oriented
Agriculture- and industry-
oriented
Overall LD risk Low High
774 L. Salvati et al.
123
Discussion
This paper provides an exploratory analysis of the rela-
tionship between the increasing level of vulnerability to LD
and the socioeconomic context in Italy during one decade
(1990–2000). The analysis was carried out at the subna-
tional scale that is the most appropriate approach for
finding evidence regarding the different forms of the
human–environment system, their past development, and
their capacity to suggest new directions of policy (Brias-
soulis 2004). Furthermore, some studies (Criado 2008;
Paudel et al. 2005) recently pointed out that data from a
wide homogeneous region or from a single country may
often provide a more reliable set of statistical units than
cross-country analysis; although the limited data variability
is an intrinsic feature of such datasets, the relevancy for
policy-making purposes could be higher.
According to the traditional environmental–develop-
ment literature, focusing on the Environmental Kuznets
Curve, accelerated wealth creation by economic growth
should be regarded as a precondition for technological
progress that in turn would provide a better environment
and the means to sustain it (Spangenberg 2001; Dinda
2004; Stern 2004; Muller-Furstenberger and Wagner
2007). To the contrary, this approach highlights the
importance of considering the socioeconomic development
as a multidimensional phenomenon, where the ‘income’
variable is only one of the dimensions (Galeotti 2007).
Results indicate that in Italy, the probability to observe a
positive trend in the level of land vulnerability during the
last years increases in low-income districts. Moreover,
other variables result as statistically associated with the
conversion from decreasing (or stable) to increasing levels
of land vulnerability, including both ‘agricultural’ variables
(INT, IRR, and LAN) and ‘environmental’ variables (GEO,
LVI, and ELE). By incorporating the spatial dimension in
the regression analysis, global fits indicate that a linear
model including district value added, a set of additional
socioeconomic variables linked to agriculture and spatial
effects may represent the increasing level of land vulner-
ability over time in different LD conditions.
On the whole, results suggest that the district income is a
significant variable determining the development stage of a
country, at both the national and regional scale, and that it
may also have feedback effects on the environment through
indirect mechanisms, for instance, by increasing the
demand for policies promoting higher environmental
quality (Bimonte 2009). The negative association of some
‘agricultural’ and ‘environmental’ variables to the DLVI
may confirm this hypothesis.
These evidences suggest that policies targeting the
economic development of local district should consider the
(potentially negative) impact of some ‘agricultural’
variables on land vulnerability. The resulting territorial
disparities could consolidate the environmental gap
between rich and poor regions (Salvati and Zitti 2009)
possibly promoting negative feedbacks, as clearly repre-
sented by the rural poverty-LD spiral which is typical of
many areas of southern Italy.
The obtained results are particularly relevant when
designing policies addressing LD. On one hand, the sign
and importance of the link among the LD variable, the
level of income, and the other covariates contribute to set
the framework for sustainable development of the Medi-
terranean region by pointing out a possible set of policy
targets at country and regional scale. On the other hand,
different results in northern and southern Italy indicate that
both the environmental and socioeconomic factors have
potentially contrasting impacts on LD in the two regions,
due to different characteristics of the natural environment,
specific economic and production contexts, social and
cultural features of the population, and differentiated
human settlement patterns in northern and southern Italy
(Salvati and Zitti 2009).
Additional factors could contribute to explain the dif-
ferent LD–development relationship observed in the two
Italian regions: the increasing level of education and
environmental awareness in the involved agents (e.g.,
farmers), more open systems of local governance, and
greater income elasticity for environmental quality repre-
sent factors potentially involved in LD and more frequently
observed in northern and central Italy than in southern Italy
(Salvati and Zitti 2009). Taken together, the implications of
these results in terms of policy implementation could be
extended to other Mediterranean regions (and Mediterra-
nean-type ecosystems) featuring strong territorial dispari-
ties and similar socioeconomic characteristics to Italy
(Montanarella 2007; Wilson and Juntti 2005).
Conclusion
Structural changes reflected in major socioeconomic
development (e.g., higher per capita income and lower
share of agriculture in total product) may lead to more
effective policies for the environmental protection and
conservation and contribute to the LD mitigation. Obvi-
ously, policies supporting economic development alone
cannot be sufficient to face (and solve) the issue of LD
mitigation, as additional drivers contribute to reverse the
(potentially) positive effect of economic growth (Span-
genberg 2001). Some of them were identified in this study
as impacting on land quality at regional scale and need
efficient policy responses at that scale. The agricultural
impact on the landscape, especially due to growing crop
intensification, excessive agricultural mechanization, and
Socioeconomic development and vulnerability 775
123
unsustainable irrigation, is an example of this process.
Moreover, other drivers could effectively work at more
disaggregated scales (e.g., land abandonment). Integrated
policy measures acting at different spatial levels (e.g.,
environmental measures applicable at the farm/local level,
social measures applicable at the municipality/district
level, and economic policies applicable at the regional/
national scales) may represent a coherent response against
several interacting factors that exacerbate LD.
According to the income disparities observed, Italy
represents an example of the possible increasing gap
fuelled by the income-driven dynamics that emerges
between lower- and higher-income areas. In such a context,
a coordination of multiscale (national, regional, local) and
multitarget (economic, social, environmental) policies is
expected to improve the effectiveness of LD mitigation
interventions, by incorporating the objective of reducing
regional disparities (Briassoulis 2004). In this perspective,
implementing the coordination of specific measures with
the final aim to avoid a downward spiral between LD and
lower income is an effective way to fight LD and deserti-
fication in southern Europe. This is in line with the prin-
ciple of spatially equitable sustainable development
(Zuindeau 2007) which should be more clearly applied in
the economically disadvantaged regions of the Mediterra-
nean basin.
Acknowledgments This study was carried out in the framework of
the Italian Project ‘‘Agroscenari’’—Adaptation Scenarios of Italian
Agriculture to Climate Changes.
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