Of the Chang Tang Wildlife Reserve in Tibet
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RANGELANDS 18(3), June 1996 91 Rangelands of the Chang Tang Wildlife Reserve in Tibet Daniel J. Millerand George B. Schaller eastern part of the cious steppes and mountains that Chang Tang Reserve sweep along northern Tibet for almost based on our research in 800 miles east to west. The chang the fall of 1993 and sum- tang, a vast and vigorous landscape mer of 1994. We also comparable in size to the Great Plains discuss conservation of North America, is one of the highest, issues facing the reserve most remote and least known range- and the implications lands of the world. The land is too cold these have for develop- and arid to support forests and agricul- ment, management and ture; vegetation is dominated by cold- conservation. desert grasslands,with a sparse cover of grasses, sedges, forbs and low shrubs. It is one of the world's last Descriptionand great wildernessareas. Location The Chang Tang Wildlife Reserve was established by the Tibetan Located in the north- Autonomous governmentin of the Region western part 1993 to protect Tibet's last, major Tibetan Autonomous wildlife populationsand the grasslands Region (see Map 1), the depend upon. In the wildernessof Reserve they Chang Tang the Chang Tang Reservelarge herdsof encompasses approxi- Tibetan antelope still follow ancient mately 110,000 square trails on their annual migrationroutes to A nomad bundled the wind while Tibetan lady up against miles, (an area about birthing grounds in the far north. Wild herding. of the size Arizona), yaks, exterminated in most of Tibet, and is the second in maintain their last stronghold in the he Chang Tang Wildlife Reserve, area in the world. The northwesternTibet, includes one of largestprotected mountainsof the Reserve,and Tibetan T Reserve is part of the chang tang still roam across the the last, largely undisturbed rangeland wild ass steppes. (Tibetan for "northern plains"), the spa- ecosystems in the world and provides The reserve retains a grassland habitatfor a diverse assemblageof wild ungulate species, several of which are endangered and endemic to the Tibetan Plateau. The southern and westernmostparts of the Reserve also afford grazing for Tibetan pastoralists and their livestock. Geographicallyiso- lated, and, until recently, off-limits to Westerners, the Reserve's rangelands and its wildlife have been little studied. MAP A cooperative wildlife conservation 1 program in the Chang Tang Reserve between the Wildlife Conservation Society and the Tibet Forest Bureau began in 1988 with rangeland surveys and investigations on the distribution and status of wildlife, primarily large ungulates. This paper provides an overview of the rangelands,wildlife and pastoral production systems in the 92 RANGELANDS 18(3), June 1996 ecosystem largely unaltered by humankind, of broad, rolling steppes broken by hills and snow-capped mountains and large basins often with saline lakes. There are no major rivers in the reserve; all drainage is internal. However, the headwaters of the Yangtze River are located just outside the reserve in the southeast. Most of the Chang Tang Reserve lies at eleva- tions between 14,500 to 16,500 feet and a number of peaks rise to eleva- tions over 20,000 feet. The Kunlun Mountains and the boundary of the Xinjiang Uygur Autonomous Region define the northern edge of the Reserve. The eastern limit of the Reserve follows the border of Qinghai Province. The "northern road", which crosses Tibet from east to west and continuesto Xinjiang, marks part of the Rangelands in the southern part of the Chang Tang Reseive at 14,500 feet used for southernand westernlimit. grazing by Tibetanpastoralists. The climate of the Reserve is harsh with no frost-freeseason. Daytime tem- Rangelands Much of the alpine is dominat- in and steppe peratures July August may ed by a plant communitycharacterized reach 75° F, but in most places, even We categorizedthe rangelandsof the by a Stipa, often known as in the height of summer, nighttime tem- Reserve purple into three major vegetation feathergrassfor its long, featheryawns. peratures are often below freezing. types: desert Winters are cold and alpine steppe, steppe, Vegetationcover in these rangelandsis extremely windy and alpine meadow. The with temperaturesthat below —40° alpine steppe usuallya meager 10 to 15 percent.Two drop is the dominant in the southern F. Annual precipitation ranges from type species of Stipa make up 50—60 per- about 12 inches in the southeast to half of the Reserve and provides the cent of total most vegetation composition. less than 4 inches in the northwest,and important grazing land for wild Other Gramineae include blue about ungulates and livestock. The desert grasses 75 percent occurs during the and sedges, another 15—20 months of is found in the uninhabited comprising July, August, and steppe percent of total vegetative September, much of it as snow and northern part of the reserve and the composition. Common forbs were a tiny Potentila, a sleet. Large areas have permafrost 2—3 alpine meadow is located in the mainly species of and feet below the surface and these southeastern of the reserve and Leontopodium legumes may margin of the and Astra- become quagmires in the summer, along streamselsewhere. genera Oxytropis making vehicle travel difficult. ga/us; makingup 10—15 percent of veg- etation composition. Low to procum- Table 1. Composition of vegetation (by percentage)of plant communities in the eastern bent shrubs such as Ceratoides corn- Chang Tang Wildlife Reserve, Tibet. Based on transects with a 0.25 m" circular plot. Potenti/la Fall 1993 pacta, sp., Myricariaprostrata survey. and Ajania fruticolosa are also found in St/pa' Mountain Carex locally Stipa rangelands. Steppe Meadows Steppe In the alpine steppe, ungulates such as Tibetan gazelle are selective feed- Number of Plots 180 60 40 ers, concentrating on particular forbs. Average % BareGround 84.5 76.4 89.4 Tibetan antelope, blue sheep and Average % Vegetation 13.9 22.1 9.5 argali are mixed feeders, consuming Average% Litter 1.6 1.5 1.1 both graminoids and forbs while the GRAMINOIDS larger ungulates like wild yak and Grasses 61.9 29.7 42.8 Tibetan wild ass Carexmoorcroftii 3.0 5.3 38.6 consume mainly Kobresiaspp. 12.4 17.5 10.1 grasses. In winter, herds of wild ass FORBS 17.8 35.0 6.4 and Tibetan antelope congregate on the DWARF SHRUBS 5.7 12.2 2.7 extensive Stipa rangelands in the southern part of the Reserve. RANGELANDS 18(3), June 1996 93 On mountain slopes the alpine layer and vegetation is dominated by steppe flora tends to be more diverse sedges of the genus Kobresia. These than on the plains. In this type, grasses meadows usually have a rich forb com- only make up about 30 percent of total ponent with genera such as Bistorta, vegetation composition and only about Gentiana, Pedicularis. They are nor- half of it is Stipa. Other grasses, such mally fed by snow and glacial melt as species of Elymus, Deyeuxia, Poa springs. Such riparian areas initiate and Festuca are also common, and plant growth earlier than other habitats species of Kobresia sedges often which depend on summer precipitation for amount to 15 percent of total composi- growth. We found in the reserve tion. A variety of forbs comprise 40 to rangelands to be spatially heterogenous ranging 50 percent of total vegetative composi- from patch to landscapescales in com- tion. These alpine grass-meadowspro- position, structure and productivity. Tibetanwild ass. vide forage for all species of wild ungu- Although fairly limited in overall plant lates including blue sheep and Tibetan species richness the rangelands are Reserve now argali. ment. The Chang Tang neverthelessquite diverse and provide the last and best In the desert steppe, which extends habitat for six wild represents place across the northern of the ungulate species affording most of these species a part reserve, and four domesticlivestock species as plant communitiesare often dominated well as a of future. variety large predators, We were especially interested to by the sedge, Carex moorcroftii, and small mammalsand birds.The diversity the shrub Ceratoides This learn how the wild ungulates coexist. compacta. in the vegetation is often subtle and type is found on sandier soils and With plant species few and vegetation easily overlooked, yet it is frequently cover do the although Stipa grasses are still part of differences that define sparse, species compete the delicate for with each other and with live- the community they are eclipsed by behavior of forage movements and foraging stock? The season is short, Carex moorcroftii.The forb component both wildlife and domesticanimals. growing in this type is also reduced, often mak- from late May or early June until nutritious ing up only 5 percentof total vegetation September, making green available.To assess composition. Expanses of Carex are Wildlife forage only briefly more common as one travels north in the impact of wildlife on the rangelands census distribu- the Reserve. Low sand dunes are The Chang Tang supports a unique we had to animals, plot and food the last sometimesfound in these grasslands. community of large mammals that tion, study habits, by — for of The alpine meadow vegetation type includes six wild ungulate species collecting droppings analysis is found in the southeastern of chiru or Tibetan antelope, Tibetan plant fragmentsin them. portion The more than other the Reserve,which receives more pre- gazelle, Tibetan argali, blue sheep, chiru, species, defines the A cipitation, and also along rivulets else- kiang or Tibetanwild ass, and wild yak. Chang Tang ecosystem. where. Plant communities here are All but the blue sheep occur only on the few small chiru populations are seden- but most animals are characterizedby a thick turf or sod Tibetan Plateau, and all probably tary, migratory.