Abstract:

Effects of short-term enclosure and cattle dung on degraded sub-alpine meadows in northwestern Yunnan province were studied in our experiment. After 4-year study, results showed that enclosure and cattle dung increased the proportion of excellent forages and the biomass of above-ground and below-ground, and led to changes of plant community composition. Species richness and biodiversity were enhanced by enclosure. Moreover, Dung and enclosure treatment reduced the dominance of Potentilla fulgens and inhibited the occurrence of Stellera chamaejasme. Dominant species shifted from Potentilla fulgens to Potentilla fulgens, Dactylis glomerata and Trifolium repens. Above-ground biomass was up to 101 g·m^-2 after 4-year experiment, which was significantly higher than control(P<0.05). Meanwhile, root system distribution changed and the proportion of root in 10~20 cm soil increased from 5% to over 10%. Therefore, short-term enclosure plus dung contributed to the rehabilitation of degraded subalpine meadow, which is of great significance to the local biodiversity protection and animal husbandry development.

Key words: Sub-alpine meadow, Plant community, Biomass, Dung

摘要：

以滇西北退化亚山草甸为对象，研究了短期封育和施用牛粪对植被的影响。通过4年的试验，结果表明，封育、施用牛粪增加了优良牧草的比例，提高了地上和地下生物量，改变了植物群落组成；封育提高了群落植物的丰富度和物种多样性；施用牛粪且封育处理中西南委陵菜（Potentilla fulgens）的优势度降低，狼毒（Stellera chamaejasme）没有发生，优势种转变为西南委陵菜、鸭茅（Dactylis glomerata）和白三叶（Trifolium repens），第4年地上生物量达到了101 g·m^-2，显著高于对照（P<0.05）。另外，封育和施用牛粪还改变了根系在土壤中的分布，10～20 cm土层中根系所占的比例由5%提高到了10%以上。可见，在短期封育的基础上施用牛粪有利于退化亚高山草甸植被的恢复，对于当地生物多样性保护、畜牧业发展具有重要意义。

关键词: 亚高山草甸, 植物群落, 生物量, 牛粪