基于功能性状的毛乌素沙地不同演替阶段适生植物筛选

沙地生态系统修复是恢复生态学研究的热点问题,适生植物筛选是修复的关键。植物功能性状反映了植物在不同环境中的生存策略,探究沙地植物功能性状及其与环境之间的关系,有助于筛选用于植被恢复的物种,为保护沙地生态系统提供理论依据。以毛乌素沙地为研究区,分析了1983-2015年间沙地典型飞播样地群落演替特征及其对环境因子的响应,建立基于10个植物功能性状的毛乌素沙地潜在种库,进一步筛选飞播恢复下沙地不同演替阶段的适生植物。研究表明:(1)飞播恢复下的毛乌素沙地植物群落分为三个演替阶段:固沙先锋物种群落、沙生植物为主的杂类草群落、中生植物为主的杂类草群落。(2)土壤因子是群落演替的主要驱动力,其中土壤全氮、土壤总有机碳、土壤硝态氮是影响群落演替的关键因素。(3)基于功能性状筛选出29种适生物种用于植被恢复,演替第一阶段可用雾冰藜、猪毛菜等,演替第二阶段可用拂子茅、无芒隐子草等,演替第三阶段可用草地风毛菊、猪毛蒿等。通过物种功能性状特征可以快速选择适合沙地退化生态系统修复的候选物种,为植被恢复提供了一定的理论支持。

Screening of suitable plants based on functional traits at different succession stages in Mu Us Sandy Land

The restoration of sandy ecosystems is currently a major focus of research in restoration ecology. In this context, screening of appropriate plant species capable of growth in local environments is an essential step in vegetation restoration programs. The functional traits of plants reflect their survival strategies in different environmental conditions, and the selection of appropriate functional traits can help identify suitable species in an effective manner. Environmental factors both drive changes in plant functional traits and promote community succession. Therefore, exploring the relationship between plant functional traits and the environment in sandy ecosystems can help in screening species that can be used for vegetation restoration, and can provide a theoretical basis for protecting such ecosystem using such species. This study was conducted in Mu Us Sandy Land, and analysed the community succession characteristics and responses to environmental factors in 30 typical flying plots from 1983 to 2015. In addition, the target species in different succession stages were identified and a potential species bank consisting of 161 species of sandy plants and 10 plant functional traits in Mu Us Sandy Land were established. Moreover, the suitable plants in different succession stages in sandy ecosystems under air-seeding restoration were further screened. The results of the study revealed the following: (1) the plant community in Mu Us Sandy Land can be divided into three successive stages; the first stage is the sand-fixing pioneer species community, the second stage is the miscellaneous grass community dominated by psammophytes, and the third stage is the miscellaneous grass community dominated by mesophytes. (2) Redundancy analysis showed that soil factors were the primary environmental driving forces of community succession, in which total nitrogen, total organic carbon, and nitrate nitrogen of soil were the crucial factors affecting community succession. (3) Finally, based on the plant functional traits, 29 species of plants suitable for growth in the sandy land were selected for vegetation restoration. The plants that could be considered to be in the first, second, and third stages of succession were Bassia dasyphylla and Salsola collina, Calamagrostis epigeios and Cleistogenes songorica, and Saussurea amara and Artemisia scoparia, respectively. The results showed that the study of functional traits and environmental characteristics at each succession stage, as well as the rapid selection of candidate species based on functional traits for restoration of degraded ecosystems, can provide references for identifying suitable species for restoration and reconstruction of sandy vegetation in the future.