Assessment of the Impacts of Land Use Changes on Nonpoint Source Pollution Inputs Upstream of the Three Gorges Reservoir

Table 6

Spearman correlation coefficients and probabilities (𝑃 value). Correlations between percentage of land use conversion within a subbasin and water quality variables. Bold coefficients indicate significant relationships.

2000	2010	Code	Area (km^2)	P_N	P_P	D_N	D_P
Upland	Pasture	5	16.85	−0.47	−𝟎.𝟓𝟕^∗	−0.53	−0.65
				0.09	0.03	0.05	0.01
Pasture	Water	12	18.84	−0.21	−0.61	−0.15	−0.70
				0.73	0.28	0.81	0.19
Upland	Water	15	12.63	𝟎.𝟖𝟏^∗∗	𝟎.𝟔𝟗^∗	𝟎.𝟔𝟒^∗	0.46
				0.00	0.02	0.03	0.16
Pasture	Upland	30	17.18	0.32	0.65	0.45	0.56
				0.54	0.16	0.37	0.24
Paddy field	Upland	32	10.17	−0.47	−0.45	−0.29	−0.55
				0.43	0.45	0.64	0.34
Shrubland	Upland	35	10.70	0.08	0.85	0.08	0.21
				0.85	0.65	0.85	0.62
Upland	Shrubland	51	12.16	−0.45	−𝟎.𝟔𝟐^∗	−0.25	−0.52
				0.14	0.03	0.44	0.08
Upland	Orchard	60	17.08	0.13	0.02	0.11	0.04
				0.70	0.95	0.70	0.90

P_N: percent changes in total nitrogen %.
P_P: percent changes in total phosphorus %.
D_N: differences in total nitrogen (kg·ha-1).
D_P: differences in total phosphorus (kg·ha-1).
𝑛=23.
^∗∗𝑃<0.05.
^∗𝑃<0.01.