MaxEnt模型下的外来入侵种香丝草在中国的潜在分布区预测

Potential distributions of a invasive species Conyza bonariensis (Compositae) in China as predicted by MaxEnt

摘要:

香丝草(Conyza bonariensis)原产于南美洲，已成为我国分布最广的恶性杂草之一。此研究基于生态位模型（MaxEnt），在大量已有居群分布点数据的基础上对其在中国的潜在分布区域进行了预测。结果表明：最冷季度平均温度、年均温、最冷月最低温、最干季度平均温度、干月降水量和最干季度降水量这6个环境因子对香丝草分布预测的影响最大；除新疆、青海、内蒙古、宁夏、黑龙江、吉林和辽宁省之外，其他地区均被预测为香丝草的适生区。目前，香丝草的潜在入侵区仍大于实际分布区，因此，预测该物种还将会进一步扩散；四川西部、云南南部、陕西北部、山东西北部、山西北部和甘肃及河北的大部分地区非常靠近已经被入侵的区域，应引起相关机构的重视，防止其进一步入侵。

Abstract:

Conyza bonariensis (L.) Crong. is a annual or biennial plant of Compositae, native to South American. It is one of the most harmful and execrable weeds in mainland China. We applied Maximum Entropy (MaxEnt) ecological niche modeling to predict this species’ potential range in China on the basis of occurence points. The results indicated that environmental parameters such as Mean temperature of the coldest quarter, Annual mean temperature, Min temperature of the coldest month, Mean temperature of the driest quarter, Precipitation of the driest month and Precipitation of the driest quarter largely influenced the distribution of Conyza bonariensis. Most Chinese provinces excluding Xinjiang, Qinghai, Inner Mongolia, Ningxia, Heilongjiang, Jilin and Liaoning are predicted the suitable habitat of Conyza bonariensis. Areas that we predict to have potential invasion were larger than that had been invaded. Therefore, Conyza bonariensis is predicted to continue to expand in China. West Sichuan, south Yunnan, north Shanxi, northwest Shandong, north Shanxi and most regions of Gansu and Hebei have not been occupied, but these areas are very close to the areas that have been invaded, so intense attention should be given to strengthen the management of these areas to prevent Conyza bonariensis from further spreading.