Table 1. Association of species richness of breeding and wintering birds of Pakistan with climate, land-use change, water discharge in rivers, and human population density.

Species richness of breeding birds and wintering birds was modeled as a function of mean seasonal temperature, total seasonal precipitation, maximum water discharge, pastures, rainfed cropland, irrigated cropland and human population in a generalized least squares model while adding the spatial covariance structure in the variance-covariance matrix. We also added interaction terms between mean seasonal temperature, total seasonal precipitation and rainfed cropland. All variables are averaged over 0.5 × 0.5° resolution. Variables were kept in their original units for interpretation. All significant values are shown in bold.

Breeding birds
	β	Std. error	t value	P-value
Mean seasonal temperature (°C)	9.4133	±2.74	3.42	<0.001
Total seasonal precipitation (mm)	15.18	±2.95	5.14	<0.001
Maximum water discharge from rivers (m3s−1)	−0.10	±0.43	−0.23	0.81
Pastures (%)	0.68	±0.77	0.88	0.37
Rainfed cropland (%)	4.72	±1.09	4.30	<0.001
Irrigated cropland (%)	0.73	±1.08	0.68	0.49
Human population	−0.100	±0.82	−0.12	0.85
Temperature:precipitation	4.04	1.42	2.83	0.004
Temperature:rainfed cropland	−4.66	1.54	−3.02	0.002
Precipitation:rainfed cropland	−1.14	0.96	−1.18	0.23
Temperature:precipitation:rainfed cropland	1.03	0.83	1.24	0.21
Wintering birds
	β	Std. error	t value	P-value
Mean seasonal temperature (°C)	20.26	±0.38	6.86	<0.001
Total seasonal precipitation (mm)	11.19	±0.06	3.95	<0.001
Maximum water discharge from rivers (m3s−1)	0.27	±0.00001	0.50	0.61
Pastures (%)	0.17	±15.49	0.13	0.89
Rainfed cropland (%)	4.06	±8.63	3.12	0.001
Irrigated cropland (%)	0.75	±4.95	0.70	0.48
Human population	0.01	±0.000001	0.21	0.83
Temperature:precipitation	3.47	1.42	2.45	0.01
Temperature:rainfed cropland	−2.65	1.66	−1.59	0.11
Precipitation:rainfed cropland	−0.63	0.92	−0.68	0.49
Temperature:precipitation:rainfed cropland	1.81	0.95	1.90	0.05