Many demographic factors such as household size, household number, and human population growth are intrinsic characteristics of the population. They are important indices to evaluate human impacts on the environment at local and regional scales. These demographic factors can vary considerably among ethnic groups sharing similar ecological landscapes, yet the role of traditional cultural practices in shaping local environmental impacts is not well known for many parts of the world.
Dr. Quan Ruichang of Xishuangbanna Tropical Botanical Garden (XTBG) and his colleagues from Kunming Institute of Zoology (KIZ) quantified land-cover changes and their relation to the habitat of the endangered black-and-white snub-nosed monkeys (Rhinopithecus bieti) in Tibet, in 2 areas populated by different ethnic groups (polyandrous Tibetans and monogamous Naxi) from 1986 to 2006.
The study area measures 75,700 ha within the Hongla Snow Mountain Nature Reserve (HSMNNR)in southeastern Tibet, located in one of the 34 biodiversity conservation hotspots of the world. The area is in the northwest of the Mountains of Southwest China Hotspot; it lies to the north of the Indo-Burma Hotspot and to the immediate east of the Himalaya Hotspot.The HSMNNR ranges from 2200 m to 5100 m above sea level elevation, characterized by extremely complex topography and climate.
Their results indicated that habitat of the monkey decreased greatly within their study area over the 20-yr period. Polyandrous and monogamous ethnic communities differed in household size, household number, population growth, and per capita and per household land use. The practice of polyandry by ethnic Tibetan appears to have reduced per capita resource consumption by reducing the growth of overall household number and increasing household size, which can mitigate the negative effects of higher human density and population growth on the environment. Ethnic Tibetan may also reduce land impacts by adhering to Buddhist customs and alternative, more sustainable means of livelihood.
Therefore, the researchers suggested that the protection of traditional cultural resources, such as polyandry and Buddhist beliefs, could be an effective way to aid biodiversity and environmental conservation efforts in this key ecosystem.
The study entitled “How Human Household Size Affects the Habitat of Black-and-White Snub-Nosed Monkeys (Rhinopithecus bieti) in Hongla Snow Mountain Nature Reserve in Tibet, China”has been published online in International Journal of Primatology, DOI 10.1007/s10764-011-9535-6.