城市化进程中撂荒地植被恢复方式对植物多样性的影响

Impact of vegetation restoration on the plant diversity of abandoned farmlands under the urbanization process

通过野外调查,研究鄱阳湖生态经济区城市化进程中农田生态系统撂荒后,自然更新和人工更新2种方式下的植物多样性和群落物种结构。结果表明:1)在撂荒地共发现42种植物,隶属22科42属,其中自然更新群落样地有10科20属,人工更新群落样地有19科34属;2)2个群落的科、属、种数在统计上差异不显著,只表现出人工更新群落稍高于自然更新群落,植物丰富度、多样性指数在统计上差异不显著,但是呈上升趋势;3)自然更新和人工更新2个群落间的植物种相似系数为0.44,自然更新和人工更新2个群落中的共有植物种类为12种,以一年生草本居多;4)应用除趋势对应分析排序方法(DCA)分析表明,2个群落结构间已形成梯度,在人工更新群落增加了多年生草本、多年生草质藤本和小灌木,人工更新减缓了植物多样性丧失的速度。在城市化圈地过程中,建议在撂荒期栽植乔木树种,有利于生物多样性的保护。

This study examined effects of vegetation restoration on the plant diversity and community composition in the abandoned farmland ecosystem of Poyang Lake Eco-economic Zone.The results are shown as follows.1） There were totally 42 plant species,42 genera and 22 families in the farmland ecosystem.For the natural regeneration community （NRC）,20 genera and 10 families were found; while for the artificial regeneration community （ARC）,34 genera and 19 families were found.2） The numbers of families,genera,species and coverage were higher in the ARC than in the NRC,but the differences were not statistically significant.The plant species abundance and diversity between two communities were not statistically significant but had an increasing trend for both ARC and NRC.3） The species similarity coefficient between two communities was 0.44.Twelve common plant species that were dominated by annual herbaceous species coexisted in both communities.4） Results of detrended correspondence analysis （DCA） showed obvious grads from NRC to ARC.Since perennial herbaceous,perennial herbaceous vine and shrub species （Rubus idaeus） were found in the ARC.Our study suggests that planting tree species would mitigate the loss rate of abandoned farmland biodiversity under the urbanization process.