深海多金属结核采矿对底栖生物影响的评价指标体系研究

Study on evaluation indicator system of deep-sea polymetallic nodule mining impact on benthos

深海矿产是满足全球金属需求的重要潜在来源。然而深海生态系统脆弱,大规模的深海采矿将对底层生态系统施加巨大压力,可能导致整个深海生态系统结构和功能在很长时间内发生重大变化。因此,深海采矿的底栖生物影响评价是开展深海采矿活动环境影响评价的主要内容,如何有效识别受扰动影响显著的底栖生物类群及其表征指标,是提升深海采矿环境影响评价结果科学性的关键。本研究基于国内外多金属结核矿区底栖生物调查和评价的125个指标,采用文献计量学方法和专家评判法,构建了包含36个指标的深海采矿对底栖生物影响的评价指标体系。指标体系包含了深海底栖生物的7个物种类别(其中巨型底栖动物、大型底栖动物和小型底栖动物的指标数量占所有指标数量的66.7%),体现了生态系统的“群落-种群-多样性-连通性”4个层面,选取了传统的物种分类学方法指标和分子生物学方法指标,突出了国内外研究的热点词汇“多样性”“生物多样性”“群落”“丰度”和“底栖有孔虫”,也强调了指示生物对评价的意义,具有较强的科学性、可行性和生态系统完整性,可以为深海采矿的环境影响评价提供兼顾科学性和可操作性的指标。

Deep-sea minerals are important potential sources to meet global demand for metals.However,deep-sea ecosystems are fragile,and large-scale deep-sea mining will exert great pressure on the sea bottom ecosystem,which may lead to major changes in the structure and function of the entire deep-sea ecosystem for a long time.Therefore,the impact assessment of deep-sea mining on benthos is an import issue of environmental impact assessment of mining activities.How to effectively identify the groups of benthos and their characterization indicators that are significantly affected by disturbance is the key to improve the scientificity of the environmental impact assessment results of deep-sea mining.Based on 125 indicators for benthos investigation and evaluation in polymetallic nodule mining areas at home and abroad,an indicator system including 36 indices for the impact assessment of deep-sea mining on benthos is constructed using the biblimetrical method and expert evaluation method in this study.The indicator system includes seven categories of deep-sea benthos,among which indices of megafauna,macrofauna,and meiofauna covering 66.7%of all indices which reflect four levels of“community”,“population”,“diversity”and“connectivity”of the bottom ecosystem.Here,traditional species taxonomy indicators and molecular biology indicators are selected,the hot topics of“diversity”,“biodiversity”,“community”,“abundance”and“benthic foraminifera”in domestic and international researches highlighted and the significance of indicator organisms also emphasized.This indicator system has strong scientificity,feasibility and ecosystem integrity and it can provide both scientific operational indicators for environmental impact assessment in deep-sea mining.