神农征镒麻种群分布模式及濒危机制的初步研究

Preliminary Study on the Population Distributive Pattern and Endangered Mechanism of Zhengyia shennongensis

摘要: 神农征镒麻是荨麻科高大草本多年生植物，系我国新发现的特有属种，具有重要的科学研究和物种保护价值。自2013年9月以来，我们对其种群构件特征、分布格局、生态因子及种群濒危状况等进行调查，主要研究结果如下：1) 新发现6个集群分布的50株以上的小种群；2) 现已知其仅分布于神农架林区武山湖一带的狭小区域，种群呈斑块状集群分布于溪沟或山坡凹沟，主要位于坡中位，生境很不稳定，遭受不定期的泥石流侵扰和损毁；3) 模式标本采集点的小种群年死亡率为67.7%，年更新率为13.8%，种群保存率为46.1%；4) 已知植株仅500余株，处于极度濒危状态，其种群濒危是自身特殊生境、特殊生态生物学性状及人类破坏的综合性结果。当务之急是通过宣传教育，发动群众使他们积极主动地保护征镒麻的特殊生境及残存种群。同时，建议对其种群生存力和引种试验予以立项研究。

Abstract: Zhengyia shennongensis, the genus name of which was given to express the famous phytotaxonomist—Prof. Wu Zhengyia’s contribution to the Chinese plant taxonomy, flora and systematics, is a relatively towering perennial herbaceous plant of Urticaceae. As a new-discovered endemic species & genus of the family in the Shennong Forest, Hubei Province, China, it is of very significance in the botanic research and regional species conservation practices. Since the September of 2013, we have focused the investigation into its population module characters, distributive pattern, ecological factors and endangered status, and the results showed as follows: 1) There were six new-discovered small populations with only over 50 individuals; 2) The species only occasionally occurred in some gullies and concave grooves of midslope along the riverbank of Wushanhu with a serious unstable habitat frequently destroyed by irregular rainwater and mud-rock flow; 3) The small population in the type specimen collecting site had 67.7% annual mortality, 13.8% refresh rate and 46.1% preserving rate from the September, 2013 to September, 2014; 4) There were over 500 individuals only recorded in the distributive area, which indicated that the species was in extremely endangered, and its critically endangered situation resulted from a combination of habitat distinctiveness, peculiar eco-biological characteristics and human firewood-cutting, herb-gathering or other interferences. The top priority should make an extensive propaganda and education for local masses to inform them the special nature and conservation significance of this rare species, so as to they could actively do some practical things to conserve these remaining populations. Meanwhile, we made a suggestion that the relevant departments should consider a project funding plan to focus its population viability analysis and off-site conservation practices.