农地整理生态环境风险综合分析与评价——以广西柳州市融安县为例

Analysis and Evaluation of Environmental Risks of Agro-Land Consolidation:A Case Study in Rongan County of Guangxi Province

我国目前对农地整理产生的生态环境问题还未引起足够重视,甚至出现认识上的误区。强大的人为压力介入土地生态系统后会导致生态环境受到极大的冲击,因此,农地整理除了改善农地的生产条件,提高农地的利用率与产出率为目标外,生态环境安全也应纳入农地整理的目标之中。农地整理应关注并双重考虑区域内土地潜力与限制之间的关系。文章应用风险评价的原理和方法,对农地整理生态环境风险及其相关的评价指标体系的不确定性进行了详细的阐述,试图探讨一种新的评价方法体系,旨在对研究区内农地整理生态环境风险进行科学合理的评价,并依据此方法对广西融安县农地整理带来的生态环境风险进行了实证研究。评价结果显示研究区内风险指数可分为五级:高风险区、较高风险区、一般风险区、低风险区、微弱风险区。评价结果还表明风险等级空间分布规律与区域人文景观具有高度相关性。

Agro-land consolidation could induce severe eco-environmental problems, which are often neglected by people. The ecosystem and environment will be destroyed if human activities affect tempestuously agro-land ecosystem. Therefore, apart from improving agro-land conditions for production and the rate of agro-land utilization and output, safety of ecosystem and environment should be taken as a major aim in the process of agro-land consolidation. It should consider the relation between land potentials and limitation factors of different areas in the process of agro-land consolidation. This paper tries to apply a new method to evaluate environmental risks of agro-land consolidation based on the theory and method of environment risk evaluation, and expatiates in detail the assessment indicators and their uncertainty, in order to evaluate environmental risk of agro-land consolidation. The authors applied this method to study the environmental risk that caused by agro-land consolidation in Rongan county of Guangxi province in order to understand fully environmental risks of agro-land consolidation. According to the index of environmental risk, there are five grades on the environmental risks in Rongan: 1) The highest risk grade; 2) The higher risk grade; 3) The general risk grade; 4) The low risk district; and 5) The lowest risk grade. The results also show that spatial distribution of the grades of environmental risk correlates significantly with human activities. There is an interrelationship between environmental risk of land consolidation and landform that affect agro-land yield potential of Rongan, and the degree of environmental risk is high where agro-land distributes widely. The intention and model of agro-land consolidation are influenced greatly by landform of the district, which leads to an increasing trend of environmental risk grade. Furthermore, causes and characters of different environmental risk resulted in different environmental risk grade. Many factors such as the railway, the highway, the river and the residential area also affect greatly environmental risk during agro-land consolidation.