山东夏津黄河故道古桑树群生态系统服务功能分析及其对区域生态系统的影响

摘要

The Shandong Xiajin Yelow River Ancient Mulberry Trees System is a model of desertification control in the floor area in the Luxibei Plain, and of sustainable development. The current study about ancient mulberry trees in Xiajin county is mainly qualitative representation, lack of quantitative research. In addition, the relevant important ecological functional assessment should not only confine to quantitative assessment which ilustrate the current condition, but also analyze the eco-service changes, derived from ecosystem structure develop, from the time di-mension. Based on quantitative eco-service assessment of the ancient mulberry tree group, this paper intend to conduct a comprehensive analysis of ecological functions of ancient mulberry group focuses on the perspective of system structure and function evolution. Quantitative evaluation results show that the system has significant eco-efficiency in water conservation, reducing sediment loss, adjust atmosphere, etc. On timescale, thanks to mulberry cultivation, ecosystem structure and services have also undergone a corresponding change. In ecosys-tem structure: Planting pioneer trees such as mulberries and other species which can tolerate hostile site conditions, improves the micro-environment. This makes it possible for other crops to grow. The mixed forests and the com-bination of forestry and agriculture protect biodiversity. What’s more, they make the structure of the ecosystems more robust, giving ful play to their functions. In terms of ecosystem services: ecosystem services of Xiajin Yelow River Ancient Mulberry Trees have shown diversified development. And its main function has transferred from supply products to leisure and entertainment functions.%夏津黄河故道古桑树群是中国鲁西北平原黄泛区防沙治沙和可持续农业发展的重要典范。当前关于夏津黄河故道古桑树的研究多为定性表述，缺少定量研究；且黄河故道古桑树群的重要生态功能评估不应只局限于定量化的现状评估，更应从时间尺度上分析其对改善区域生态状况、影响区域生态系统服务变迁中的作用。基于此，本文在定量化评估黄河故道古桑树群生态系统服务功能的基础上，着重从系统结构演化及功能变迁角度对古桑树群的生态功能进行全面分析。定量化评估结果表明，系统内古桑树在涵养水源、减少泥沙流失、净化空气等方面生态效益显著。在时间尺度上，得益于桑树种植，区域生态系统结构及服务功能也发生了相应变化。在生态系统结构方面：以桑为主的耐贫瘠立地条件的先锋树种改善了局地环境，使得种植其他农作物成为可能；多树种的混交林以及林农复合生产，维护生物多样性的同时丰富了生态系统结构，又充分发挥了生态系统功能。在生态系统服务功能方面：夏津黄河故道古桑树群生态系统服务功能向多元化发展，且其主要功能已由产品供给转为休闲娱乐功能。