In September 30th 2019, a group of scientists from China, UK, the Netherlands, Spain and Belgium published ‘China’s pig relocation in balance’ in Nature Sustainability. The study highlights that China’s pig relocation will protect water quality in the southern provinces, where people are suffering from severe water pollution. However, such relocation may transfer pollution to new regions with large areas of forests and fragile natural grasslands.

In 2015, the Chinese government banned livestock production in some regions (called non-livestock production regions, NLPRs) to control surface water pollution near vulnerable water bodies. In total, 90,000 NLPRs had been established by 2017, covering 0.82 million km2 land and shutting down 0.26 million pig farms. As a consequence, the number of slaughtered pigs decreased by 46 million head year-1 between 2014 and 2017. The NLPRs policy is unprecedented globally in terms of the geographical area and number of farms affected, as well as its speed of implementation.

However, it is unclear which farms and regions may take over the market share. This question is crucial because the consumption of pork in China is forecasted to double between 2010 and 2050. Pig production is expected to be transferred from southern regions where there are many vulnerable watercourses, to southwest and northeast provinces. The main reasons for selecting these provinces are the current low pig population density and the large land availability to apply pig manure, relative to other areas. This policy seems attractive at first glance: total nutrient losses to water courses in the southern provinces should decrease markedly, and less developed regions will benefits from more businesses and subsidies, promoting local economies.

However, the pollution burden associated with pig production may also be transferred. This is concerning because the southwest and northeast have large areas of forests and fragile natural grasslands, respectively. In addition, technologies to manage manure and minimize ammonia emissions do not appear to have followed new production systems, due to the lack of appropriate technologies, investments and incentives in these new areas. Estimated health costs to citizens of air pollution are comparable to the profits of pig production (1.3 to 11 euros head-1 and ~4.2 euros head-1 respectively). This suggests that, on balance, the new pig development regions may not benefit, when all the costs are considered.

Overall, the NLPRs and pig relocation policies risk decreasing surface water pollution in the southeast at the expense of increasing air emission and groundwater pollution in the southwest and northeast, which already have high nitrogen losses. However, this group of international agriculture and environment experts suggest that these tradeoffs however could be minimized through i) holistic spatial planning of livestock production which considers all economic, environmental and social constraints in an integrated manner, ii) adopting strategies to properly allocate manure to local cropping systems at sustainable nutrient loading rates, and iii) promoting the use of pollution mitigation technologies.

The study concludes that, in identifying non-livestock production regions and potential development regions, we must consider the multiple risks to the environment, including surface water pollution, air pollution, soil degradation, and threats to human health, but crucially, also the risks associated with long-distance transport of livestock, including the spreading of animal diseases.

Zhaohai Bai from Center for Agricultural Resources Research CAS, and Shuqin Jin from Research Center for Rural Economy MOARA are the co-first author of this paper. This paper was supported by National Key R&D Program of China, the NSFC of China, Key Laboratory of Agricultural Water Resources-CAS, the Key Research Program-CAS, the UK-China CINAg project and MINECO-Spain (EU commission and UPM funded). 

Linkage

Bai, Z., Jin, S., Wu, Y., Ermgassen, E., Oenema, O., Chadwick, D., Lassaletta, L., Velthof, G., Zhao, J., Ma, L. 2019. China’s Pig Relocation in Balance. Nature Sustainability. https://doi.org/10.1038/s41893-019-0391-2.

https://www.nature.com/articles/s41893-019-0391-2