Information Technology Reference
In-Depth Information
Symmetric log-ratio transformation not only solves the essential zero problem and
the problem of constrained total land area, but also linearizes the non-linear relation-
ships between land use patterns and their driving factors.
5 Spatial Allocation
The input parameters used in the module for spatially allocating changes in land use
area reflect local, regional and historical characteristics of the pattern changes of re-
gional land uses [5]. Specific steps are shown in the following figure.
(i) If a certain land use type existed in the previous simulation year, and its stability is
less than 1, the spatial allocation module will calculate the distribution probability, sum
of the compensation factor and stability factor, which are used as the allocation prob-
ability:
L
=
P
+
C
+
S
.
(10)
i
,
k
i
,
k
k
k
where
L
i,k
is the allocation probability of the
k
th land use type in grid
i
;
P
i,k
is the dis-
tribution probability of the
k
th land use type in grid
i
;
C
k
and
S
k
are the compensation
and stability factors, respectively.
(ii) When the compensation factor
C
k
is nearly 0,
L
i,k
consists of the distribution
probability
P
i,k
and compensation factor
C
k
as follows:
=+
(11)
(iii) Within each spatial allocation step, DLS excludes those pixels with a decreasing
trend for a certain kind of land use type from obtaining new area of that kind of land use
type [6]. If the spatial allocation does not allow the configuration of stability, then the
land use type with the largest
L
i,k
is allocated to grids without enough area of land use
types.
LPC
.
ik
,
ik
,
k
6 Summary
DLS is a software tool developed based on the DLS model for the dynamic simulation
of the land use pattern changes. This paper introduces the main procedures of DLS
including framework, parameter configuration, function modules and results output. It
can measure the influence of driving factors that are closely associated with changes in
the land use pattern, including natural conditions, socioeconomic factors and even land
use management policies. It can simulate the spatial-temporal process of pattern
changes of land uses and export maps of pattern changes of land uses with high spatial
and temporal resolution by setting conversion rules of land use types and designing
change scenarios.
Search WWH ::
Custom Search