滇西外来物种薇甘菊（Mikania micrantha）跨境入侵机制与扩散动态

Mikania micrantha, as an alien plant species and aggressive invader, is widely acknowledged as one of the worst weeds in the world, as well as in China. Studying invasive mechanisms and spreading dynamics of M. micrantha can certainly provide scientific guidance necessary to facilitate prevention and control of biological invasion. Up to now, only limited basic researches are available focusing on the relevance between invasive mechanism and spreading dynamic of this species and regional environmental heterogeneity. Previous field survey work revealed M. micrantha is aggressively spreading across the China-Myanmar border region and extending its range along natural corridors like the valley area of Nujiang basin in West Yunnan, suggesting the invasion and spreading patterns of this alien plant are tightly correlated with the transboundary effect in border region and the "Corridor-Barrier" function in Longitudinal Range-Gorge Region. In this application, we choose West Yunnan as study region, mainly covering Nujiang basin and its western area, to conduct the research on three parts: (1) to reconstruct the invasive history of M. micrantha, and display its changing patterns and trends as well, based on multiple information collection methods like expert consulting, literature survey, herbarium specimens checking, etc.; (2) to identify current occurrence range and spatial distribution patterns of M. micrantha through combining results from field investigation and remote sensing and image interpretation, and then to identify key environmental factors which are significantly responsible for driving the invasion and spreading process of this species; and (3) to build multi-period climate scenarios via analyzing changing patterns and trends of climatic condition, and furthermore simulate potential suitable region for M. micrantha and predict its spreading dynamics under the background of climate change. This project will play an important role in enriching scientific references for developing prevention and control strategies of M. micrantha and other invasive plants in border area of plateau mountainous region, Southwest China.

薇甘菊是一种危害性很大的外来入侵植物，研究其入侵机制与扩散动态对于风险评估和防控管理有重要意义，但目前关联区域环境异质性驱动的基础性研究较少。薇甘菊在滇西地区表现出沿边境强势入侵和沿怒江河谷快速扩散的趋势，暗示其入侵机制和扩散动态与边境效应和纵向岭谷"通道－阻隔"作用有密切关系。本申报项目选择滇西怒江流域及以西范围为案例区，基于多源数据的收集和分析，梳理薇甘菊跨境入侵历史过程与特征；判识主要发生区范围及空间分布现状，筛选关键驱动因子；结合多时段气候情景，预估潜在适生区的空间分布格局及其动态变化特征。课题的实施，可以为发展我国西南高原山地环境外来入侵植物防控对策提供科学依据。

薇甘菊是一种危害性很大的外来入侵植物，对所入侵地的自然和经济生态具有很大的威胁，研究我国滇西地区异质环境条件对薇甘菊入侵和扩散的驱动机制具有科学价值和现实意义。本项目选择滇西怒江流域及以西范围为案例区，基于多源数据的收集和分析，梳理了薇甘菊在滇西地区的入侵历史，明晰了薇甘菊在滇西地区的地理分布特征，揭示了多模式多气候情景下怒江流域的多时段气候变化特征，判识了怒江流域薇甘菊分布和扩散的关键驱动因子，预估了薇甘菊潜在适生区的分布格局及其对气候变化响应的特征。研究结果表明，（1）薇甘菊经缅甸跨境入侵我国西南中缅边境地区，主要分布于5个州市的85个乡镇，在怒江流域集中在南部干支流河谷；（2）薇甘菊适生于1000 m以下海拔、半淋溶土或人造土土壤、农用耕地附近、靠近水体和靠近公路的环境条件；（3）2006-2100年期间怒江流域整体温度有所降低而降水有所增多，但无显著变化趋势；（4）当前气候背景下怒江流域薇甘菊潜在适生区分布集中在南部干支流河谷，并沿干流河谷向北延伸至流域中部。在气候变化大背景下，2006-2045年期间怒江流域薇甘菊潜在适生区分布有所增大， 2006-2100年期间怒江流域薇甘菊潜在适生区分布在不同排放情景下表现不同，但均无显著变化趋势。已有薇甘菊监测网络受管理职能重叠、覆盖范围有限和专项经费短缺的限制，难以发挥有效作用。项目研究结果建议参考薇甘菊适生环境条件范围来开展调查和监测活动，尤其需要在怒江流域中部以南沿干流区域构建监控体系，并结合早期防控措施来应对薇甘菊的威胁。项目研究结果不仅有利于在滇西地区实施长期有效的外来入侵生物管理措施，还可以为建设和发展我国西南中缅边境和其它经济欠发展地区的生物入侵管理体系提供科学参考。