畜牧业对区域范围内的食草动物承载能力的影响
M Oesterheld1, O E Sala, S J McNaughton
1Departamento de Ecología, Facultad de Agronomía, Universidad de Buenos Aires, Argentina.
Nature
|March 19, 1992
概括
农业生态系统中的畜牧生物量比自然生态系统的生物量大得多,即使具有相似的初级生产率. 畜牧业实践显著增加了草食生物质和体型.
科学领域:
- 生态生态学 生态生态学
- 农业科学 农业科学
- 动物学 动物学
背景情况:
- 草食动物的营养水平属性与陆地生态系统的初级生产率相关.
- 了解农业与自然系统中的食草动物生物量对于生态系统管理至关重要.
研究的目的:
- 量化比较南美农业生态系统中的牲畜生物质和尺寸结构与本地草食动物.
- 在区域范围内评估畜牧业做法对食草动物种群的影响.
主要方法:
- 在南美农业生态系统中,通过对初级生产率的25倍梯度分析牲畜生物质.
- 在农业生态系统和未经管理的生态系统中,比较初级生产率和食草动物生物质/体型之间的关系.
主要成果:
- 农业生态系统中的牲畜生物质显示出类似的斜率,但与未经管理的生态系统相比,y截面要大得多.
- 在农业生态系统中,每单位初级生产率的草食生物量大约是自然生态系统的十倍.
- 牲畜的体型随着初级生产率的增加而增加,反映了在自然生态系统中观察到的模式.
结论:
- 在农业系统中,畜牧业实践显著提高了草食生物质和体型.
- 这项研究提供了第一个区域范围的定量证据,证明畜牧业对牲畜种群的影响与本地食草动物相比较.
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