草原养鸡可提高环境可持续性和经济效益

刘美珍*, 王冰雪, Colin P. Osborne, 蒋高明*

*通讯作者

中国科学院植物研究所植被与环境变化国家重点实验室

英国谢菲尔德大学动物与植物科学系

PLoS One. 2013;8(1):e53977. doi: 10.1371/journal.pone.0053977. Epub 2013 Jan 23.

背景：过度放牧引起草原退化, 对中国大部分半干旱地区尤其是华北地区的畜牧业和环境可持续性都构成了威胁。尽管中国政府为恢复退化草原作出了巨大努力，但由于对当地社区的经济利益考虑不足，大量投资取得的效果却不尽人意。

方法/主要发现：通过控制性田间试验验证了我们的假设：利用天然草地作为鸡的栖息地和饲料资源，发展草原养鸡替代传统的畜牧业，将提高环境可持续性和牧民收入。研究发现，草原地上植物生物量从放牧绵羊的25 g m^-2提高到养鸡的84 g m^-2。与围栏草地相比，养鸡并不显著降低地上植物生物量，但增加了60%的根系生物量（p<0.01）。与传统绵羊放牧相比，草原养鸡显著提高了土壤表层含水量（0-10cm），由5%提高到15%。养鸡对土壤容重无明显影响，而传统绵羊放牧使0-10cm土层土壤容重比对照增加35%（p<0.05）。更重要的是，当地牧民的经济收入比传统的养羊方式提高了6倍左右。从生态学意义上讲，这样一个创新的解决方案使得大片退化的草原得以自然恢复。草原还提供了一种高质量的有机家禽产品，可在大城市销售。

结论/意义：草原养鸡是提高环境可持续性和经济收入的一种创新的替代方案，而不是对传统游牧牧区制度的挑战。该研究在技术上可能适用于世界上其他大型退化草地。

Chicken farming in grassland increases environmental sustainability and economic efficiency

Meizhen Liu*, Bingxue Wang, Colin P. Osborne, Gaoming Jiang*

* Correspondence author

The State Key Laboratory of Vegetation and Environment Change, Institute of Botany, The Chinese Academy of Sciences, Beijing, China

PloS One, 2013, 8(1): e53977.

BACKGROUND: Grassland degradation caused by overgrazing poses a threat to both animal husbandry and environmental sustainability in most semi-arid areas especially north China. Although the Chinese Government has made huge efforts to restore degraded grasslands, a considerable attempt has unfortunately failed due to an inadequate consideration of economic benefits to local communities.

METHODOLOGY/PRINCIPAL FINDINGS: A controlled field experiment was conducted to test our hypothesis that utilizing natural grasslands as both habitat and feed resources for chickens and replacing the traditional husbandry system with chicken farming would increase environmental sustainability and raise income. Aboveground plant biomass elevated from 25 g m(-2) for grazing sheep to 84 g m(-2) for chicken farming. In contrast to the fenced (unstocked) grassland, chicken farming did not significantly decrease aboveground plant biomass, but did increase the root biomass by 60% (p<0.01). Compared with traditional sheep grazing, chicken farming significantly improved soil surface water content (0-10 cm), from 5% to 15%. Chicken farming did not affect the soil bulk density, while the traditional sheep grazing increased the soil bulk density in the 0-10 cm soil layer by 35% of the control (p<0.05). Most importantly, the economic income of local herdsmen has been raised about six times compared with the traditional practice of raising sheep. Ecologically, such an innovative solution allowed large degraded grasslands to naturally regenerate. Grasslands also provided a high quality organic poultry product which could be marketed in big cities.

CONCLUSION/SIGNIFICANCE: Chicken farming is an innovative alternative strategy for increasing environmental sustainability and economic income, rather than a challenge to the traditional nomadic pastoral system. Our approach might be technically applicable to other large degraded grasslands of the world, especially in China.