敬信湿地弃耕稻田恢复演替年限对植物群落多样性的影响

Effects of Restoration Succession Years of Abandoned Paddy Fields on Plant Community Diversity in Jingxin Wetland

图们江下游的敬信湿地是吉林省唯一的近海湿地,在维护地区生态平衡方面有着至关重要的作用。近年来,敬信湿地地区许多稻田被废弃,其面积逐年增加。弃耕稻田作为一种自然演替而来的半自然湿地,对区域生物多样性具有显著影响,但在自然演替过程中弃耕稻田植物群落的变化机制尚不明确。通过现场和文献调查,确定图们江下游敬信湿地的生境情况,采用空间序列代替时间序列的方法,比较不同弃耕年限稻田和自然湿地的植物物种群落,以确定植物多样性在自然演替过程中的变化。结果表明,不同弃耕年限稻田和自然湿地植物共99种,隶属于33科64属,主要为湿地草本植物,并以湿生和水生植物为主;从群落特征来看,敬信湿地以莎草科(Cyperaceae)、蓼科(Polygonaceae)和禾本科(Poaceae)植物为优势种;随弃耕年限增加,湿地植物群落优势种逐渐接近自然湿地植物群落优势种,弃耕稻田植物多样性远高于自然湿地,并随着演替时间推移而降低,进而接近自然湿地。但与同纬度湿地相比,弃耕稻田湿地植物演替速率较慢,建议在弃耕稻田的生态恢复中关注土壤水分和有机质的补充,并加强管理和保护。

The Jingxin Wetland,located in the lower reaches of the Tumen River,plays a vital role in maintaining regional ecological balance as the only offshore wetland in Jilin Province.In recent years,many paddy fields in the Jingxin Wetland area have been abandoned,and the area has increased year by year.As a semi-natural wetland formed by natural succession,abandoned paddy fields have a significant impact on regional biodiversity,but the mechanism behind the transition of plant communities through natural succession remains unclear.In this study,we focused on the Jingxin Wetland,and identified its site and biological habitat characteristics by performing a site survey and literature survey.To determine the changes of plant diversity in the process of natural succession,we compared the plant species and communities of natural wetland with semi-natural wetland of different abandoned times by using space series analysis instead of time series analysis.A total of 99 plant species belonging to 64 genera of 33 families were identified in natural wetland and abandoned paddy fields.The species primarily consist wetland hydrophyte herbaceous,and aquatic plants.Based on the community characteristics,Cyperaceae,Polygonaceae,and Poaceae were the dominant species in the Jingxin Wetland.As the time of abandonment increased,the dominant species of the semi-natural wetland plant community shifted towards the dominant species of the natural wetland plant community.The plant diversity of the abandoned paddy fields was much higher than that of the natural wetland;however,the diversity decreased as succession time progressed and began to resemble the natural wetland community.Nevertheless,compared with wetlands at the same latitude,the succession rate of the abandoned paddy fields was slower,thereby highlighting the influence of soil,water,and organic matter in the subsequent restoration of abandoned paddy fields and the need to continuously strengthen wetland management and protection.