main cause of this decline is overgrazing. He estimates that the annual pasture production is 10.6 × 108 kg of dry matter (DM), whereas the livestock feeding requirement is 16.8 × 108 kg DM, leaving a deficit of 37%. In addition, more than 7334 km2 of grasslands have been cultivated for cereal production, causing subsequent destabilization and sand desertification.

Liu argues that grazing time and intensity strongly influence animal performance, vegetation regrowth, protection, and future production from these grasslands. The later tillering stages of grasses and branching in early flowering stages of legumes are the best times for grazing to begin. After a period of grazing, the grasses should be allowed to regrow to at least 15 cm before further grazing. Liu recommends that grazing be forbidden during the first 12–18 days after the grass turns green in spring and for 30 days after the cessation of growth at the end of the season.

Professor Zhu Tingcheng and colleagues (1989) of the Northeast Normal University have done research on the relationship among increasing human population, increasing livestock numbers, and the declining condition of grasslands in northeastern China.

DESERTIFICATION CONTROL

Shelterbelt Systems Since the forest steppe zone has had some forest cover in the past, the establishment of shelterbelts and increased fuel production by sand-stabilizing shrubs and low trees could be important to a rangeland restoration strategy. During the past decade, research by the Institute of Applied Ecology in the Wulanaodu Research Station, at the eastern end of the Horqin Sandy Land, South of the Xilamulun [Xar Moron] River, has contributed to a better understanding of the potential for rangeland restoration.

Cao (1984) describes Wulanaodu, a production brigade in the Wengniute Banner of Inner Mongolia. The brigade covers 22,667 hectares. Over the last 30 years, its human population has doubled to 1310 people, whereas livestock have increased 2.3 times to 16,846 animals. The rangeland has been devastated by overgrazing to such a degree that herbs that grew to 1.5 m in the 1950s now reach only 50–60 cm. The desertification and alkalinization of the soil have led to the degradation of pastureland and a decline in livestock productivity. The livestock cannot get enough fodder even during the peak growth period in June, a situation that sometimes lasts for several years. The mortality of overwintering livestock is reported to be as high as 7% in dry years.

According to Cao, primary productivity of the pasture is low and unstable. In recent years, the hay yield per hectare has been only 1100–1500 kg on mowed grasslands and 450–600 kg in grazing areas. The mowed grasslands and the grazing "banks" cover 5467 hectares and support 16,846 head of livestock, for an average of 0.3 hectare per head, compared with 1–2 hectares per head in European mountain pasturage.



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