Quantifying the Pollution Loading from Livestock and Poultry of Family Farm—Based on the Sample of Counties in Hunan Province

Based on the sample of 14810 sizable livestock and poultry farms, the optimal loading of animal manure per hectare is calculated with the theory of Soil Surface Nutrient Balance which can be used to get the alarm value of manure from livestock and poultry and judge the damage to the environment. The result shows that pollution of sizable livestock and poultry breeding in towns is greater than any other areas. Therefore, the suggestion of balancing the conflict between sizable livestock breeding and ecological pollution to cultivated land is put forward and the optimal scale of livestock breeding is also calculated according to the alarm value.