McNaughton SJ, Banyikwa FF, McNaughton MM
S. J. McNaughton and M. M. McNaughton, Biological Research Laboratories, Syracuse University, Syracuse, NY 13244-1220, USA; and Serengeti Wildlife Research Centre, Post Office Box 661, Arusha, Tanzania. F. F. Banyikwa, Department of Botany.
Science. 1997 Dec 5;278(5344):1798-800. doi: 10.1126/science.278.5344.1798.
Experiments in Serengeti National Park, Tanzania, provide direct evidence that large, free-ranging mammalian grazers accelerate nutrient cycling in a natural ecosystem in a way that enhances their own carrying capacity. Both nitrogen and sodium were at considerably higher plant-available levels in soils of highly grazed sites than in soils of nearby areas where animal density is sparse. Fencing that uncoupled grazers and soils indicated that the animals promote nitrogen availability on soils of inherently similar fertility and select sites of higher sodium availability as well as enhancing that availability.
在坦桑尼亚塞伦盖蒂国家公园进行的实验提供了直接证据，表明大型自由放养的食草哺乳动物以一种提高自身承载能力的方式加速了自然生态系统中的养分循环。在重度放牧区域的土壤中，氮和钠的植物可利用水平显著高于附近动物密度较低区域的土壤。将食草动物与土壤隔离开的围栏实验表明，这些动物促进了本质上肥力相似的土壤中氮的有效性，还选择了钠有效性较高的地点，并提高了钠的有效性。
