Long-Term Ecological Effects of Sheep Grazing in Alpine Ecosystems and its Integration with Management, 2011

We propose to further develop two unique experimental studies in contrasting alpine ecosystems (running from 2000 in Setesdal Vesthei and 2002 in Hol) to address several important new research questions: The overall aim is to facilitate sustainable management of sheep grazing in alpine habitats by providing a scientific basis for relating management alternatives (sheep density) to specific long-term ecological effects of grazing. The initial 6-8 yrs of these two sheep grazing experiments revealed that short-term effects differ for plants, invertebrates, rodents and birds. In addition, effects depend on factors like sheep density and habitat productivity. However, these short-term impacts may differ from long-term ones, because many effects are likely to be indirect, mediated through plants and processes in the soil. Specific objectives are to perform the first experimental, long-term (10 year) study of sheep grazing effects in two contrasting ecosystems (rich and poor), to assess (1) long-term and cascading ecosystem effects; (2) tree-line dynamics along a taiga-tundra ecotone and (3) soil physical and biogeochemical processes and properties; (4) to link density dependent sheep grazing ecology and life history to long-term plant development to understand better how climate and density affect ungulate life history at different temporal scales, and (5) to integrate data from ecological experiments with management scale data on animal density and satellite derived vegetation maps (i.e. up-scaling processes).Our previous project has already demonstrated a direct impact on management in the Setesdal Vesthei and Hardangervidda region, and the outcomes from this proposal will be applicable to sheep grazing in alpine areas and also relevant to semi-domestic rein deer (summer) grazing management.

本研究拟进一步推进两项针对不同高山生态系统的特色实验研究（塞特斯达尔韦斯特黑（Setesdal Vesthei）实验始于2000年，霍尔（Hol）实验始于2002年），以解答若干重要的全新研究问题：本研究的总体目标是通过构建科学依据，将放牧管理方案（绵羊密度）与放牧产生的特定长期生态效应建立关联，从而助力高山生境中绵羊放牧的可持续管理。两项绵羊放牧实验的前6至8年观测结果显示，植物、无脊椎动物、啮齿类与鸟类所受的短期影响存在显著差异。此外，放牧效应还受绵羊密度与生境生产力等因素的调控。然而，由于多数放牧效应可能通过植物与土壤过程间接介导，短期影响与长期影响往往存在差异。本研究的具体目标包括：在两类不同的生态系统（富营养型与贫营养型）中开展首次针对绵羊放牧效应的长期（10年）实验研究，以达成以下目标：（1）评估生态系统的长期与级联效应；（2）探究泰加林-苔原生态交错带的林线动态变化；（3）分析土壤物理过程、生物地球化学过程及其属性特征；（4）将依赖密度的绵羊放牧生态学与生活史特征，与长期植物群落动态建立关联，以更深入地理解气候与密度因素在不同时间尺度上如何影响有蹄类动物的生活史；（5）将生态实验获取的数据，与动物密度的管理尺度数据以及卫星遥感植被图（即尺度升级过程）进行整合。我们此前的研究项目已证实，该研究对塞特斯达尔韦斯特黑与哈当厄尔维达（Hardangervidda）地区的放牧管理具有直接指导作用；本提案的研究成果不仅可应用于高山地区的绵羊放牧管理，也对半家养驯鹿（夏季）的放牧管理具有参考价值。