Manure management and pollution levels of contract and non-contract livestock farming in Vietnam

Le Thi Thu Huong; Yoshifumi Takahashi; Hisako Nomura; Cao Truong Son; Takeru Kusudo; Mitsuyasu Yabe

doi:10.1016/j.scitotenv.2019.136200

Manure management and pollution levels of contract and non-contract livestock farming in Vietnam

Sci Total Environ. 2020 Mar 25:710:136200. doi: 10.1016/j.scitotenv.2019.136200. Epub 2019 Dec 19.

Authors

Le Thi Thu Huong¹, Yoshifumi Takahashi², Hisako Nomura³, Cao Truong Son⁴, Takeru Kusudo⁵, Mitsuyasu Yabe⁶

Affiliations

¹ Laboratory of Environmental Economics, Graduated School of Bioresources and Bioenvironmental Sciences, Kyushu University, Japan.
² Laboratory of Environmental Economics, Department of Agricultural and Resource Economics, Faculty of Agriculture, Kyushu University, Japan.
³ Center for Promotion of International Education and Research, Faculty of Agriculture, Kyushu University, Japan.
⁴ Faculty of Environment, Vietnam National University of Agriculture, Viet Nam.
⁵ Organization for WISE Program, Tokyo University of Agriculture and Technology, Japan.
⁶ Laboratory of Environmental Economics, Department of Agricultural and Resource Economics, Faculty of Agriculture, Kyushu University, Japan. Electronic address: yabe@agr.kyushu-u.ac.jp.

PMID: 31923657
DOI: 10.1016/j.scitotenv.2019.136200

Abstract

In analyzing contract farming of livestock production, many studies have focused on the economic aspect. This paper offers the environmental issue by investigating manure management and pollution levels of contract farming (CF) and non-contract farming (NCF) livestock producers in Vietnam. By surveying 270 pig farms and applying logit model, we found that commercial pigpen type of CF reduces the probability of manure separation, while larger garden area and knowledge of composting increase it. By analyzing the wastewater samples collected from 59 farms and employing nearest neighbor matching technique, this paper indicated that CF reduces the pollutants' concentrations in effluents. Using OLS regression models, we found out that manure separation contributes to a reduction in nutrient matters, while biogas plant or combination of biogas plant and stabilization ponds helps to diminish organic matters. The study results suggest that the government should regulate the minimum required land area for installation of the combined manure treatment plants (MTPs). Additionally, to recycle manure and improve nutrient matters in effluent, advanced technologies for separating solid manure are extremely necessary for CF producers. Furthermore, we recommend the government to build mechanisms to compel agribusiness firms engaging in their liability for the environmental side effects caused by their CF producers.

Keywords: Contract farming; Manure treatment; Manure treatment plant; Pig production; Waste recycling.