The Scientific World Journal

Research Article

Modelling Favourability for Invasive Species Encroachment to Identify Areas of Native Species Vulnerability

Table 1

Variables used to model the distribution of Trachemys scripta and Mauremys leprosa.


Abbreviations	Variable	Abbreviations	Variable

Spatial situation
La	Latitude (°N)⁽¹⁾	Lo	Longitude (°E)⁽¹⁾

Topography
A	Mean altitude (m)⁽²⁾	SE	Southward exposure degree⁽³⁾
	Difference altitude (m) (calculated from altitude)	WE	Westward exposure degree⁽³⁾
S	Slope (°) (calculated from altitude)

Climate
	Mean relative air humidity in July at 07:00 (%)⁽⁴⁾	Dfro	Mean annual number of frost days (minimum temperature 0°C)⁽⁶⁾
	Annual relative air humidity range (%) (=)		Mean relative air humidity in January at 07:00 (%)⁽⁴⁾
	Mean temperature in January (°C)⁽⁴⁾	RMP	Relative maximum precipitation (=MP24/Prec)
	Mean temperature in July (°C)⁽⁴⁾	ContI	Continental index⁽⁶⁾
Temp	Mean annual temperature (°C)⁽⁴⁾	PIrr	Pluviometric irregularity⁽⁷⁾
Inso	Mean annual insolation (h/year)⁽⁴⁾	ROff	Mean annual runoff (mm)⁽⁵⁾
SRad	Mean annual solar radiation (kWh/m²/day)⁽⁴⁾	DPre	Mean annual number of days with precipitation 0.1 mm⁽⁴⁾
	Annual temperature range (°C) (= − )	DStrS	Mean annual number of storm in summer⁽⁶⁾
MP24	Maximum precipitation in 24 h (mm)⁽⁴⁾	Win	Mean annual number of route of winter (km/h)⁽⁶⁾
Perm	Soil permeability⁽⁵⁾	DOvc	Mean annual number of overcast days⁽⁶⁾
HumI	Humidity index⁽⁶⁾	DClear	Mean annual number of clear days⁽⁶⁾
Prec	Mean annual precipitation (mm)⁽⁴⁾	DFog	Mean annual number of fog days⁽⁶⁾
AET	Mean annual actual evapotranspiration (mm) (=	DFogW	Mean annual number of fog days in winter⁽⁶⁾
PET	Mean annual potential evapotranspiration (mm)⁽⁴⁾	DFogS	Mean annual number of fog days in summer⁽⁶⁾
DHail	Mean annual number of hail days⁽⁶⁾	DStor	Mean annual number of storm days⁽⁶⁾
DSno	Mean annual number of snow days⁽⁶⁾

Land cover
Natural vegetation
PAST	Pasture⁽⁸⁾	DForeH	Deciduous forest and hardwood⁽⁸⁾
Bush	Bush⁽⁸⁾	MxtFor	Mixed forest⁽⁸⁾
ScleV	Sclerophyllous vegetation⁽⁸⁾	ConiFor	Conifer forest⁽⁸⁾
NMead	Natural meadows⁽⁸⁾	Mountain	Mountain areas⁽⁸⁾
Crops
IHerRice	Irrigated herbaceous crops and rice fields⁽⁸⁾	Fruit	Fruit⁽⁸⁾
DHerVin	Dry herbaceous crops and vineyard⁽⁸⁾	Agricul	Agricultural areas⁽⁸⁾
Olive	Olive⁽⁸⁾	AgricuLNa	Agricultural land with natural vegetation⁽⁸⁾
Water surfaces
LK	Reservoirs and lakes⁽⁸⁾	OW	Other wetlands⁽⁸⁾
RV	Rivers⁽⁸⁾
Other use
BeachD	Beaches and dunes⁽⁸⁾	Mining	Mining area and dumps⁽⁸⁾
Urban	Urban zone⁽⁸⁾	LinearUr	Urban linear infrastructures⁽⁸⁾

Other human activities
	Distance to the nearest highway (km)⁽¹⁾	U500	Distance to the nearest urban centre with more than 500 000 inhabitants (km)⁽¹⁾
U100	Distance to the nearest urban centre with more than 100 000 inhabitants (km)⁽¹⁾	HPd	Human population density in 2000 (number of inhabitants/km²)⁽⁹⁾

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