气候变化背景下我国扁蓿豆潜在适生区预测

扁蓿豆（Medicago ruthenica）是我国北方地区重要的豆科饲草资源，在草地改良、人工草地建设及生态修复等方面起重要作用，研究气候变化背景下我国扁蓿豆潜在适生区分布对其种植区划及种质资源保护具有重要意义。本研究采用最大熵模型（MaxEnt）预测了气候变化背景下扁蓿豆的适宜性生境分布区域及影响其分布的主导气候因子。结果表明，当前气候背景下我国扁蓿豆的适生区主要集中在内蒙古、黑龙江、新疆、甘肃、四川、西藏、吉林、陕西、云南、河北、青海中东部、山西、辽宁、山东东部、河南西北部、宁夏等地区；影响当代扁蓿豆适生区分布的主导因子是最干旱月降水量（bio14）、最冷季度降水量（bio19）、最湿润月降水量（bio13）、最热季度平均温度（bio10）；间冰期我国扁蓿豆的适生区较大，分布范围较广，而最佳适生区较小，仅占4.79%，从末次冰期冰盛期开始到未来CCSM4-rps26-2070等5个气候情景下我国扁蓿豆的适生区总面积较间冰期变小，而最佳适生区面积增加，5个气候情景的适生区面积和范围变化较小，受气候变化影响相对较弱。

Prediction of the Potential Distribution of Medicago ruthenica in China under Climate Change

Medicago ruthenica is an important leguminous forage resource in northern China. It plays an important role in grassland improvement,artificial grassland construction and ecological restoration. Under the background of climate change,the distribution of potential suitable areas of Medicago ruthenica in China is studied. Its planting zoning and germplasm conservation are of great significance. Using a maximum entropy model (MaxEnt),we predicted the suitable habitat distribution area and the contribution of the dominant climatic factors of Medicago ruthenica under six types of climate scenarios. The results showed that the suitable area of Medicago ruthenica in China under current climate is approximately 4.5814 million km²,accounting for 46.90% of the total land area in China,were mainly concentrated in Inner Mongolia,Heilongjiang,Xinjiang,Gansu,Sichuan,Tibet,Jilin,Shaanxi,Yunnan,Hebei,central,Eastern Qinghai,Shanxi,Liaoning,Eastern Shandong,Northwestern Henan,Ningxia and other places. Precipitation of driest month (bio14),precipitation of coldest quarter (bio19),precipitation of the wettest month (bio13) and mean temperature of warmest quarter (bio10) was found to be dominant in influencing the geographic distribution of Medicago ruthenica. The suitable area of Medicago ruthenica of interglacial period are large and wide distribution,but the most suitable area was small,accounting for only 4.79%. From the Last Glacial Maximum to the 2070 in the future,the suitable habitat area of the Medicago ruthenica becomes smaller than that of the Last interglacial climate under the five climate scenarios,while the area of the best suitable area is increased. In the five climate scenarios,the area and scope of the habitat of the Medicago ruthenica vary relatively little,and it would be weakly impacted by climate change.