Table 4. Potential predictor variables, abbreviations, data sources and resolutions used to analyse differences in species abundance in wetlands of the Yangtze River floodplain.

Variables	Abbreviation	Unit	Range	Source	Resolution
Lake land area	LA	km2	0.20 ~ 216.04	landsat TM/ETM+	30 m
Water area	WA	km2	0.13 ~ 1612.16	landsat TM/ETM+	30 m
February mean air temperature	TEMP	°C	7.30 ~ 11.20	http://www.cma.gov.cn/2011qxfw/2011qsjgx/	0.5° × 0.5°
Mean January precipitation	MP	mm	3.70 ~ 158.60	http://www.cma.gov.cn/2011qxfw/2011qsjgx/	0.5° × 0.5°
Littoral slopes	SLOPE	°	0.00 ~ 2.75	http://srtm.csi.cgiar.org	90 m
Coefficient of variance of littoral slopes	SLOPECV	no unit	0.00 ~ 1.49	http://srtm.csi.cgiar.org	90 m
Normalized difference vegetation index	NDVI	no unit	0.20 ~ 0.43	landsat TM/ETM+	30 m
Net primary productivity	NPP	g/m2 month−1	52.00 ~ 98.60	http://neo.sci.gsfc.nasa.gov/	0.1° × 0.1°
Habitat heterogeneity	NDVICV	no unit	0.08 ~ 0.35	landsat TM/ETM+	30 m