Impacts of mining on the diversity of benthic macroinvertebrates - A case study of molybdenum mining area in Luanchuan county

Abstract

Mineral exploitation is one of the human activities that seriously affect freshwater ecosystems. It is of great significance to study the impact of mining on the α and β diversity of macroinvertebrates. This study reveals the response of taxonomic and functional α and β diversity of macroinvertebrates to mining activities in the Luanchuan molybdenum mining area. A total of 40 sets of macroinvertebrates, sediment and water samples in the Taowan North River (TR), Yu River (UR) and Hongluo River (HR) in the molybdenum mining area were collected. The results show that: 1) the mining activities led to obvious differences in the environmental factors of the three rivers. The heavy metals in the sediments and water bodies of TR and UR showed different degrees of exceedance, while there was no exceedance of heavy metals in HR; 2) The taxonomic and functional α diversity was much lower in the TR and the UR than in the HR. The concentrations of heavy metals in sediments and water bodies were significantly negatively correlated with the taxonomic and functional α diversity; 3) Mineral extraction resulted in significant differences in macroinvertebrate β diversity among the three rivers. The taxonomic and functional β diversity of the macroinvertebrate communities in TR and UR was much higher than that in HR. The turnover and nestedness of functional β diversity showed significant differences. Functional β diversity was more obviously affected by heavy metal exceedance than taxonomic β diversity. Nestedness were more sensitive to exceedance of heavy metals than turnover. The results of this study can provide a theoretical basis for ecological restoration and protection of rivers in mining areas.