关键词: 辽西北, 乡土草, 生态修复, 层次分析法, 综合评价

Abstract: The low hilly area of northwest Liaoning Province is a region with arid climate,barren soil,and serious soil erosion. So far,no grass species suitable for regional ecological restoration have been selected. A scientifical evaluation system needs to be established. In this study,we established a comprehensive evaluation model to evaluate ecological restoration ability of native grass species in Liaoning Province using analytic hierarchy process (AHP),and evaluated the ecological restoration ability of 15 dominant native grass species. According to the frequency of plants in 280 survey plots,15 native grasses were selected for evaluation,among which Lespedeza daurica had the highest frequency (75.6%). According to the scores given by experts,environmental adaptability,soil and water conservation ability and reproductive ability were selected as three primary indexes,and drought resistance,cold resistance,spread,salt tolerance,root biomass,growth rate,tillering/branching number,and other parameters were selected as 14 secondary indexes. Among the 3 primary indexes,the weight of environmental adaptability was the highest (0.488 1),followed by soil and water conservation ability,and the reproductive ability was the lowest. Among the 14 secondary indexes,the weight of cold resistance,drought resistance,growth rate,tillering/branching number were higher than others. Based on the performance of native grass to be evaluated,the comprehensive score of its ecological restoration ability was calculated. The results showed that Artemisia stechmanniana,Arundinella hirta,Themeda triandra,Bothriochloa ischaemum and Achnatherum sibiricum were classified as excellent ecological restoration grass species. This study could provide an important reference for ecological restoration in northwest Liaoning.

Key words: Northwest Liaoning province, Semi-arid region, Ecological restoration, Analytic hierarchy process, Comprehensive evaluation