短花针茅草原主要植物种群及群落特征对放牧强度季节调控的响应

在探究荒漠草原主要植物种群及群落特征对放牧利用方式的响应规律时,不仅可以明确荒漠草原植物群落的变化规律,亦可以探讨作为荒漠草原群落重要组成部分的主要植物种群变化特征和规律,二者结合有利于掌握荒漠草原植物群落结构和功能的变化形式。试验选取内蒙古自治区苏尼特右旗短花针茅荒漠草原为研究对象,设置6个放牧处理,采用随机区组排列(3个区组,即3次重复),选取主要植物种群(短花针茅、无芒隐子草和碱韭)、植物群落的高度、盖度、密度和现存量为研究指标,运用最优母序列关联度分析方法,探讨主要植物种群、群落在放牧处理间、放牧季节间的关联序。结果表明,春季休牧+夏季重度放牧+秋季适度放牧的SA1处理区可以作为草地可持续利用的首选,其次是全年适度放牧的SA5处理区。采用最优母序列关联度评价草地具有简单便捷的特点。

Responses of Main Plant Population and Community Characteristics of Stipa breviflora Steppe to Seasonal Regulation of Grazing Intensity

Investigating the response law of the main plant population and community characteristics of desert steppe to grazing use patterns can not only elucidate the change law of the plant community in desert steppe, but also can explore the change characteristics and rules of the main plant population as an important part of the desert steppe community. The combination of the above two aspects is conductive to grasp the variations in the structure and function of the plant community in desert steppe. In this study, the Stipa breviflora desert steppe in Sonid Right Banner of Inner Mongolia was used as the research object. A total of 6 grazing treatments were set up and arranged in random blocks (3 blocks, 3 repeats). The main plant population (Stipa breviflora, Cleistogenes songorica and Allium polyrhizum) as well as the height, coverage, density and existing stocks of the plant community were used as evaluating indicators to assess the relational order of the main plant populations and communities among different grazing treatments and grazing seasons by using optimal parent sequence correlation degree analysis. The results showed that the SA1 treatment mode of rest grazing in spring + heavy grazing in summer + moderate grazing in autumn was recommended as the first choice for sustainable grassland use, followed by the SA5 treatment mode of moderate grazing throughout the whole year. Furthermore, the optimal parent sequence correlation degree analysis method exhibited simplicity and convenience in grassland evaluation.