荒漠草原生态恢复与重建:人工植被推动下水分介导的系统响应、生态阈值与互馈作用

Study on ecological restoration and reconstruction of desert steppe:A review

荒漠草原(生态区)横贯我国西北地区东部,生态地位十分重要。近二十年来,通过封育禁牧、退耕还林(草),植被覆盖显著改善,但是生态系统质量和稳定性依然不高。由于长期将荒漠草原单纯视作草原的一部分,对其生态系统过渡性、脆弱性和复杂性本质特征认识不足,造成了荒漠草原生态学研究与区域生态建设实践之间不同程度的脱节。在分析荒漠草原生态区未来在我国生态安全格局中突出的但是被一定程度上忽视的地位的基础上,进一步归纳了荒漠草原生态系统的一般特征,指出了生态恢复与重建研究中存在的主要问题。进而以人工植被引入荒漠草原生态工程为案例,分析了人工植被驱动荒漠草原生态恢复与重建的过程与机制,归纳了“植被-水文-土壤”互馈作用驱动生态系统层级响应模式,并展望了今后的发展趋势与研究方向。

Desert steppe(ecological region),traversing the eastern part of Northwest China,has important ecological significance,and is very fragile.In the recent two decades,the vegetation coverage has been improved significantly,but most of the grassland have shown various degrees of degeneration.For a long time,the desert steppe has been regarded as a part of grassland,and its transitional nature has not been fully understood.As a result,the ecological research of desert steppe has lagged far behind the practice of regionally ecological construction.Therefore,this paper further emphasizes the prominent position of desert steppe in the Chinese ecological security pattern in the future,which has been neglected for a long period,and then summarizes the general ecosystem characteristics of desert steppe to point out the main problems in the research of ecological restoration and reconstruction.Finally,the process and mechanism of artificial vegetation driving ecological restoration and reconstruction of desert steppe are analyzed,and the future research direction and tasks are proposed.