• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文会议>2008世界草地与草原大会论文集 >Are drought‐related crashes in pastoral cattle herds predictable ? — More evidence of equilibrium dynamics from the douthern Ethiopian rangelands
【24h】

Are drought‐related crashes in pastoral cattle herds predictable ? — More evidence of equilibrium dynamics from the douthern Ethiopian rangelands

机译：牧民牛群中与干旱有关的崩溃是否可以预测？ -来自埃塞俄比亚南部牧场的平衡动力学的更多证据

获取原文
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Drought routinely ravages the Greater Horn of Africa, especially rangelands.Drought leads to massive reductions in livestock productivity and increased risk of famine and poverty for people.Traditional pastoral systems were better able to cope with drought, but restoring traditional pastoralism is nearly impossible in many cases.Other strategies focus on helping people deal with drought using market development and opportunities for livelihood diversification.Livestock remain the core economic engine for pastoralism and understanding how risks and returns to livestock vary over time is important to devise tactics to improve the situation.Ellis and Swift (1988) proposed that some East African pastoral systems are non‐equilibrial, meaning that vegetation and herbivore dynamics are controlled by precipitation ; carrying capacity and livestock‐induced ecological degradation lose relevance.Livestock death losses would be unpredictable and vary with rainfall.For the semi‐arid Borana Plateau we posit a different theory based on dynamic equilibrium concepts (Desta and Coppock 2002).In this situation, drought impacts on livestock production are predictable due to interactions between stocking rates and precipitation.When stocking rates are high the regional herd is more likely to crash if annual precipitation is low.Cattle crashes in 1983‐5,1991‐3, and in 1998‐9 lead to the hypothesis that periodicity of crashes is related to time needed for the regional herd to grow to a vulnerable size.Desta and Coppock (2002 ; p.450) predicted that the next cattle crash would occur by 2005.The purpose of this paper is to verify the cattle prediction and illustrate whether ecological change has occurred as a result of pastoral activity (Mesele, 2006).
机译：干旱通常会破坏非洲大角，特别是牧场;干旱导致牲畜生产力大幅度下降，人们遭受饥荒和贫穷的风险增加;传统的牧业系统能够更好地应对干旱，但在许多地方恢复传统的牧民主义几乎是不可能的其他战略着重于利用市场发展和谋生手段的多样化来帮助人们应对干旱。畜牧业仍然是畜牧业的核心经济引擎，了解牲畜的风险和回报如何随时间变化对于制定改善情况的策略很重要。斯威夫特和斯威夫特（1988）提出，某些东非牧草系统是非平衡的，这意味着植被和草食动物的动力学受降水控制;承载力与牲畜导致的生态退化失去相关性，牲畜死亡损失将无法预测，并且会随降雨而变化。对于半干旱的博拉纳高原，我们基于动态平衡概念提出了不同的理论（Desta and Coppock 2002）。由于放牧率和降水之间的相互作用，干旱对牲畜生产的影响是可以预见的。当放牧率高时，如果年降水量低，该地区的牛群更容易崩溃。1983年5月，1991-3年和1998年牛群崩溃9得出这样的假设，即撞车的周期性与区域畜群成长到脆弱规模所需的时间有关.Desta和Coppock（2002; p.450）预测，下一次牛撞车将在2005年发生。本文旨在验证牛群的预测，并说明是否由于牧民活动而发生了生态变化（Mesele，2006）。

著录项

相似文献

  • 外文文献
  • 中文文献
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号