Research on Nonpoint Source Pollution Assessment Method in Data Sparse Regions: A Case Study of Xichong River Basin, China

Table 2

TN and TP loads calculation of all kinds of pollution sources in 2012 (unit: ton⋅yr⁻¹).

Types	Types of pollution source	TN	Proportion/%	TP	Proportion/%
Land use
Dry land	Fertilizer	340.84	39.24	9.47	14.55
Paddy field		97.28	11.20	4.24	6.52
Orchard		2.36	0.27	0.10	0.15
Natural woodland		19.85	2.29	1.50	2.30
Waste land		3.63	0.42	0.15	0.23
Subtotal		463.96	53.42	15.46	23.76
Urban land	Urban runoff	24.77	2.85	0.65	1.00
Livestock and poultry
Cattle	Livestock and poultry	10.05	1.16	0.51	0.78
Pig		70.85	8.16	8.70	13.37
Sheep		11.09	1.28	0.43	0.66
Poultry		5.15	0.59	0.51	0.78
Subtotal		97.13	11.18	10.16	15.61
Population
Rural population	Rural sewage	202.96	23.37	27.87	42.82
Urban population	Urban Sewage	79.67	9.17	10.94	16.81
Total		868.5	100.00	65.08	100.00