The effect of mining on the diversity of invertebrates in Peri-urban Dar es Salaam

The present study pertains to address the effect of mining activities on the diversity of invertebrates in three mining sites of Wazo, Bunju and Kitonga in peri-urban Dar es Salaam, in order to assess the impact of these activities on the biodiversity of the this habitat, an area that is poorly studied. Each site was divided into two areas: the mined area and the adjacent unmined area. In each of the two areas, three sampling plots were established, in which collection of invertebrates was carried out using three methods: pitfall traps, timed hand collecting, and sweep nets. A total of 4,448 specimens comprising 360 species were captured. Of these, 1,149 specimens (156 species) came from Wazo, 1,011specimens (156 species) from Bunju and 2,288 specimens (197 species) from Kitonga. The difference in abundance was significant. Within-site there was higher abundance in unmined areas at Wazo and Bunju, while at Kitonga the mined area had a higher abundance of invertebrates compared to surrounding unmined area. Unmined parts of all three sites had a higher invertebrate richness than the mined parts. The younger site, Kitonga had also higher richness compared to Bunju and Wazo. Wazo and Bunju unmined areas had a higher invertebrate diversity than adjacent mined areas, while at Kitonga mined and unmined areas did not differ in diversity. It is concluded that mining activities had negative effects on invertebrate diversity. Recommendations are given on actions that need to be taken.