参照点位法下的参照状态在草原生态系统损害基线判定中的应用分析

生态环境损害基线的判定是环境损害鉴定与评估的基础与前提。参照点位法作为目前损害基线判定中使用最为广泛的方法之一,有效弥补了历史数据不完善的问题。在基线判断的过程中,参照点位选择的不同,会导致判定基线的参照状态不同,进而影响对人类干扰程度的判定和损害基线的基准值的设定。但目前缺乏统一的对草原生态系统参照状态的讨论与分析。提出了草原生态系统参照点位法的评价指标体系,对文献资料中的样点进行分类和筛选,形成4种参照状态,选择最优的参照状态对损害基线进行判定,并以内蒙古锡林郭勒盟锡林浩特典型草原区为案例进行实例分析。结果表明:对于自然保护区、草原实验站宜采用极小干扰状态和历史状态作为基线标准。对于实施了人为正向干扰的地区宜采用最佳可获得状态作为基线标准。对于草原的其他大部分地区,宜采用最低干扰状态作为基线标准。

Study on damage baseline assessment of grassland ecosystem in reference site method with different reference conditions

The ecosystem damage baseline assessment is the foundation and premise of the environmental damage identification and evaluation. As the most widely used method in baseline assessment, reference site method can overcome the problem of lacking historical data. In the process of the assessment, choosing the different reference site can cause different reference conditions, which affect the degree of anthropogenic disturbance and the set value of damage baseline. At present, there is no universal discussion and evaluation about the reference condition of grassland ecosystem. In this paper, we proposed evaluation index of the reference site method in grassland ecosystem, categorized and filtered the samples in bibliography to form four conditions, and then chose the most accurate condition to determine the damage baseline. We took the typical grassland of Xilinhot in Xilingol League as the case study. The result showed that for natural reserve and experimental stations, it is appropriate to use minimally disturbed condition and historical condition as the baseline; for the areas where human implemented positive interference, it is appropriate to use the best attainable condition as the baseline; for the most other parts of grassland, it is appropriate to use the least disturbed condition as the baseline.