How does livestock and poultry restricted zone policy affect stability of China’s hog market?

doi:10.3969/j.issn.1004-1524.2023.05.24

Acta Agriculturae Zhejiangensis ›› 2023, Vol. 35 ›› Issue (5): 1195-1210.DOI: 10.3969/j.issn.1004-1524.2023.05.24

• Agricultural Economy and Development • Previous Articles Next Articles

How does livestock and poultry restricted zone policy affect stability of China’s hog market?

LIU Wei(), TAO Jianping()

Hubei Rural Development Research Center, College of Economics and Management, Huazhong Agricultural University, Wuhan 430070, China

Received:2022-06-05 Online:2023-05-25 Published:2023-06-01

Abstract

Abstract:

Based on the panel data of 30 provinces (autonomous regions, municipalities) in China (excluding of Hongkong, Macao, Taiwan and Tibet) from 2006 to 2020, the livestock and poultry restricted zone policy (RZP) was selected as a quasi-natural experiment, and a generalized difference-in-difference model and a moderated mediation model were adopted to evaluate the impact of this policy on the stability of hog market and to reveal its path. It was found that RZP significantly exacerbated hog price fluctuation, and the tightening of environmental protection restrictions had a negative impact on the stability of hog market. The policy worked through the moderated mediation effects path. Specifically, under the pressure of environmental protection, RZP forced the improvement of the scale breeding level, which could offset the direct aggravation effect of RZP on hog price fluctuation. However, in those regions with more severe swine epidemics, the stabilization effect of scale breeding on price fluctuation was weakened, and the direction of the effect was even reversed. As a result, RZP intensified the hog price fluctuation through its own direct effect and the conditional indirect effect of scale breeding. Further empirical test showed that the stabilization effect of hog price fluctuation of scale farming with different scales had different responses to pig epidemic. Small-scale farming and large-scale farming would aggravate hog price fluctuation due to the swine epidemics, while medium-scale farming was not significantly affected. The callback of environmental protection measures in response to the outbreak of African swine fever had boosted hog supply and had flattened price fluctuations during the epidemic period. In order to ensure the healthy development of hog market, the government should implement flexible environmental protection measures, strengthen environmental supervision, increase efforts to support small and medium-scale farming, and improve the epidemic prevention and control mechanism.

Key words: market stability, livestock and poultry restricted zone policy, scale breeding, pig epidemics, moderated mediation effect model

CLC Number:

F326.3

LIU Wei, TAO Jianping. How does livestock and poultry restricted zone policy affect stability of China’s hog market?[J]. Acta Agriculturae Zhejiangensis, 2023, 35(5): 1195-1210.

Figures/Tables 10

References 41

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年份Year	省(区、市)Province (Autonomous region, Municipality)
2014	福建、广东、广西、贵州、河南、湖北、湖南、江西、浙江、重庆 Fujian, Guangdong, Guangxi, Guizhou, Henan, Hubei, Hunan, Jiangxi, Zhejiang, Chongqing
2015	安徽、海南、山东、山西、上海、四川、云南 Anhui, Hainan, Shandong, Shanxi, Shanghai, Sichuan, Yunnan
2016	北京、甘肃、河北、黑龙江、吉林、江苏、辽宁、内蒙古、宁夏、青海、陕西、天津、新疆 Beijing, Gansu, Hebei, Heilongjiang, Jilin, Jiangsu, Liaoning, Inner Mongolia, Ningxia, Qinghai, Shaanxi, Tianjin, Xinjiang

年份Year	省(区、市)Province (Autonomous region, Municipality)
2014	福建、广东、广西、贵州、河南、湖北、湖南、江西、浙江、重庆 Fujian, Guangdong, Guangxi, Guizhou, Henan, Hubei, Hunan, Jiangxi, Zhejiang, Chongqing
2015	安徽、海南、山东、山西、上海、四川、云南 Anhui, Hainan, Shandong, Shanxi, Shanghai, Sichuan, Yunnan
2016	北京、甘肃、河北、黑龙江、吉林、江苏、辽宁、内蒙古、宁夏、青海、陕西、天津、新疆 Beijing, Gansu, Hebei, Heilongjiang, Jilin, Jiangsu, Liaoning, Inner Mongolia, Ningxia, Qinghai, Shaanxi, Tianjin, Xinjiang

变量 Variable	处理组Treat group		控制组Control group		全样本Full sample
变量 Variable	平均值 Mean	标准差 Standard deviation	平均值 Mean	标准差 Standard deviation	平均值 Mean	标准差 Standard deviation
R×P	1	0	0	0	0.409	0.492
F	0.138	0.095	0.259	0.185	0.188	0.151
F'	0.122	0.084	0.226	0.169	0.165	0.136
L	0.211	0.170	0.193	0.119	0.203	0.151
M	0.079	0.040	0.068	0.045	0.075	0.043
C	0.049	0.042	0.049	0.038	0.049	0.041
B	0.086	0.050	0.064	0.036	0.077	0.046
I	0.026	0.059	0.013	0.010	0.020	0.046
S	0.343	0.188	0.542	0.213	0.425	0.221
D	0.419	0.647	0.631	1.093	0.506	0.863

变量 Variable	处理组Treat group		控制组Control group		全样本Full sample
变量 Variable	平均值 Mean	标准差 Standard deviation	平均值 Mean	标准差 Standard deviation	平均值 Mean	标准差 Standard deviation
R×P	1	0	0	0	0.409	0.492
F	0.138	0.095	0.259	0.185	0.188	0.151
F'	0.122	0.084	0.226	0.169	0.165	0.136
L	0.211	0.170	0.193	0.119	0.203	0.151
M	0.079	0.040	0.068	0.045	0.075	0.043
C	0.049	0.042	0.049	0.038	0.049	0.041
B	0.086	0.050	0.064	0.036	0.077	0.046
I	0.026	0.059	0.013	0.010	0.020	0.046
S	0.343	0.188	0.542	0.213	0.425	0.221
D	0.419	0.647	0.631	1.093	0.506	0.863

变量 Variable	回归1 Regression 1		回归2 Regression 2
变量 Variable	估计系数 Coefficient	t	估计系数 Coefficient	t
R×P	0.111^***	9.495	0.095^***	(9.817)
L	0.133^***	4.273	0.122^***	(4.497)
M	-1.339^***	-14.132	-1.309^***	(-15.011)
C	1.429^***	7.699	1.330^***	(7.420)
B	0.212^*	1.955	0.174^*	(1.917)
I	0.193	1.446	0.263^**	(2.153)
D	0.018^***	3.789	0.013^**	(2.713)
常数项	0.170^***	7.978	0.159^***	(8.052)
Constant
R²	0.461		0.488

How does livestock and poultry restricted zone policy affect stability of China’s hog market?

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变量 Variable	回归7 Regression 7	回归8 Regression 8	回归9 Regression 9	回归10 Regression 10	回归11 Regression 11	回归12 Regression 12	回归13 Regression 13	回归14 Regression 14
R×P	0.192^*** (12.609)	0.197^*** (12.772)	—	—	—	—	0.078^*** (4.301)	0.068^*** (4.480)
S	—	—	-0.359^*** (-9.303)	-0.303^*** (-10.344)	-0.268^*** (-7.765)	-0.212^*** (-8.336)	-0.176^** (-2.747)	-0.143^** (-2.755)
D	—	—	—	—	0.033^* (2.042)	0.026^* (1.757)	0.026^* (1.889)	0.019^* (1.817)
S×D	—	—	—	—	0.018^* (1.769)	0.016^* (1.702)	0.011^* (1.783)	0.010^* (1.782)
常数项 Constant	0.346^*** (55.662)	0.349^*** (27.163)	0.096^*** (2.992)	0.094^*** (3.307)	0.071^* (1.928)	0.075^** (2.316)	0.107^*** (2.987)	0.106^*** (3.431)
R²	0.471	0.519	0.428	0.458	0.444	0.470	0.472	0.497

模型 Model	调节变量的取值水平 Level of mediation variable	估计值 Coefficient	偏差 Bias	标准误 Standard error	95%置信区间95% Confidence interval
模型 Model	调节变量的取值水平 Level of mediation variable	估计值 Coefficient	偏差 Bias	标准误 Standard error	P	BC
回归13	低值 Low value	0.001	0.001	<0.001	[0.001,0.035]	[0.001, 0.035]
Regression 13	中值 Middle value	0.003	0.001	0.001	[0.001, 0.026]	[0.001, 0.025]
	高值 High value	0.004	0.001	0.001	[0.002, 0.025]	[0.002, 0.025]
回归14	低值 Low value	0.001	-0.001	<0.001	[0, 0.026]	[0, 0.025]
Regression 14	中值 Middle value	0.002	-0.001	0.001	[0.001, 0.021]	[0.001, 0.020]
	高值High value	0.004	-0.000	0.002	[0.002, 0.024]	[0.001, 0.023]

被解释变量 Explained variable	变量 Variable	散养 Free-range farming		小规模养殖 Small-scale farming		中规模养殖 Middle-scale farming		大规模养殖 Large-scale farming
被解释变量 Explained variable	变量 Variable	估计系数 Coefficient	t	估计系数 Coefficient	t	估计系数 Coefficient	t	估计系数 Coefficient	t
F	R×P	0.078^***	4.301	0.119^***	7.401	0.075^***	4.368	0.097^***	6.439
	S	0.176^**	2.747	-0.134^***	-3.761	-0.613^***	-3.972	-0.243^*	-1.767
	D	0.014^*	1.715	0.006^*	1.811	0.025^**	2.609	0.024^***	2.958
	S×D	-0.011	-0.483	0.049^*	1.885	-0.035	-0.897	0.040^*	1.950
	常数项Constant	0.282^***	6.891	0.194^***	4.908	0.104^***	3.656	0.148^***	5.785
	R²	0.472		0.463		0.489		0.469
F'	R×P	0.068^***	4.480	0.102^***	8.072	0.070^***	4.551	0.081^***	6.687
	S	0.143^**	2.755	-0.113^***	-3.812	-0.441^***	-3.324	-0.235^**	-2.130
	D	0.010^*	1.703	0.005^*	1.804	0.019^**	2.110	0.018^**	2.316
	S×D	-0.010	-0.482	0.034^*	1.864	-0.031	-0.883	0.032^*	1.921
	常数项Constant	0.249^***	7.351	0.178^***	5.477	0.110^***	4.567	0.137^***	5.976
	R²	0.497		0.490		0.506		0.497

[1]	WANG Anbang, HE Ke, ZHANG Junbiao. Effect of health consciousness on pro-environmental behavior of scale breeding farmers: based on payment willingness for environmentally friendly feed [J]. , 2019, 31(10): 1745-1757.
[2]	LENG Bibin, JI Xueqiang, ZENG Hao, TU Guoping. Study on technical efficiency of large-scale pig breeding in China [J]. , 2018, 30(6): 1082-1088.

变量 Variable	回归15 Regression 15		回归16 Regression 16
变量 Variable	估计系数 Coefficient	t	估计系数 Coefficient	t
R×P⁰	0.149^***	8.186	0.127^***	7.476
R×P¹	0.225^***	5.895	0.194^***	6.852
R×P²	0.241^***	8.861	0.230^***	8.960
R×P³	0.053^*	1.984	0.026^**	2.046
R×P⁴	0.028	0.565	0.036^**	2.121
R×P⁵	-0.019	-1.416	0.020^*	1.740
常数项 Constant	0.185^***	7.513	0.171^***	7.898
R²	0.571		0.599

变量 Variable	回归15 Regression 15		回归16 Regression 16
变量 Variable	估计系数 Coefficient	t	估计系数 Coefficient	t
R×P⁰	0.149^***	8.186	0.127^***	7.476
R×P¹	0.225^***	5.895	0.194^***	6.852
R×P²	0.241^***	8.861	0.230^***	8.960
R×P³	0.053^*	1.984	0.026^**	2.046
R×P⁴	0.028	0.565	0.036^**	2.121
R×P⁵	-0.019	-1.416	0.020^*	1.740
常数项 Constant	0.185^***	7.513	0.171^***	7.898
R²	0.571		0.599