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Page 2 of 17 Zhang et al. Carbon Footprints 2025, 4, 36 https://dx.doi.org/10.20517/cf.2025.29

conclusion, our findings suggest that successful implementation of targeted emission reduction measures is
conducive to the sustainable development of animal husbandry, while also maintaining a balance with ecosystem
functions under the multifaceted ecological landscape of QTP.

Keywords: Greenhouse gas, global warming potential, life cycle assessment, yak grazing farm, Qinghai-Tibet
Plateau

INTRODUCTION
Global livestock husbandry - both extensive and intensive - is a major source of greenhouse gas (GHG)
emissions, including carbon dioxide (CO ), methane (CH ), and nitrous oxide (N O). It is contributing an
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estimated 18% of global anthropogenic GHG emissions . Meanwhile, the increasing demand for meat,
[1]
milk, and wool products has driven the rapid expansion of livestock husbandry, especially in developing
countries, further increasing global GHG concentrations . Consequently, GHG emissions from livestock
[2,3]
[4]
husbandry have received worldwide attention . Similarly, many field-level studies on GHG budgets of
European agroecosystems, particularly those focusing on intensive and semi-intensive grasslands, report
similar trends . This approach has also been applied to diverse landscapes worldwide, including
[5-7]
agricultural fields and undisturbed sites in the Middle East and Northeast United States, and temperate
steppe pastures under medium and heavy grazing in both the United States and Inner Mongolia, China .
[3,8]
The extent to which livestock farming contributes to GHG emissions in high-altitude grassland ecosystems
is still largely unexplored.
The Qinghai-Tibetan Plateau (QTP) is the highest (more than 4,000 m above sea level) and largest grassland
[10]
[9]
area of both the Eurasian continent and China . It plays a crucial role in the livestock industry . Yaks (Bos
grunniens) and Tibetan sheep (Ovis aries) are the two major ruminant species that play an important role in
the Tibetan range, and due to their strong adaptability and productive performance . There are
[11]
approximately 13 million domestic yaks and 50 million Tibetan sheep grazing on the QTP . Furthermore,
[12]
recent trends indicate a consistent increase in livestock numbers on the QTP, driven by growing market
demands and government support for pastoralist livelihoods. This escalating grazing intensity poses a
significant threat to these fragile alpine ecosystems, underscoring the urgent need to quantify its climatic
impacts . Additionally, QTP is an ecological functional zone and provides ecological security for China and
[6]
[13]
Asia due to its unique geographical location and climate characteristics . Grasslands are distributed widely
across the high plains and mountains of the QTP, and they cover the source areas of many major Asian
rivers (i.e., the Yangtze River, the Yellow River and the Lan Cang River). Approximately 40% of the world’s
population depends on or is influenced by these rivers . Therefore, QTP plays a critical role in both
[14]
China’s animal production and Asia’s broader environmental stability . It has been an extensive reservoir
[15]
of soil carbon for the past several thousand years due to its slow soil decomposition rates and relatively
favorable photosynthetic conditions compared with cold, high-latitude ecosystems .
[15]

In addition to being a fundamental forage supply for livestock, the alpine grasslands of QTP are also of
paramount importance in regulating the global GHG budget . The escalating demand for animal products
[12]
[16]
has resulted in higher stocking rates on the native alpine grasslands . A primary consequence of
overgrazing is the widespread degradation of the grassland ecosystem, which severely influences livestock
management and alters the dynamics of GHG fluxes, including CO , CH , and N O . Although grazing-
[17]
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induced grassland degradation and associated carbon loss are global concerns in high-altitude regions, the
mechanisms and magnitudes underlying them can vary significantly across diverse ecological conditions.
For instance, in the European Alps, long-term historical grazing has led to more stabilized, albeit often