| Substrate amendment and tolerant species choice are key factors for restoration of mining wastelands containing heavy metals.In this work, potted tests were performed to explore the effects of different treatments on tailings substrate properties and growing development of leguminous species. The main research conclusions were as follows:(1) Dry matter increased obviously of C. tora, S. cannabina and C. juncea after chicken manure amended copper tailings substrate. In which, the shoot biomass (9.36 g) was the highest of C. juncea MA32 treatment. Total nitrogen increased of C. juncea after chicken manure amended copper tailings substrate. In which, the root total nitrogen (17.11g.kg-1) was highest of C. juncea MA32 treatment, the shoot total nitrogen (26.03g.kg-1) was highest of C. juncea MA16 treatment. C. juncea had root nodules after chicken manure amended copper tailings substrate, while does not exist root nodule of C. tora and S. cannabina.(2) Soil available Zn of C. tora and available Cu, Zn of C. juncea reduced after chicken manure amended copper tailings substrate. In which, soil available Zn (3.31 mg·kg-1) was lowest of C. juncea MA 16 treatment. Soil electrical conductivity C. juncea present declined trends, soil electrical conductivity (129.50 dS·m-1) was lowest of MA 16 treatment.(3) Soil microbial biomass C increased of C. tora, S. cannabina and C. juncea after chicken manure amended copper tailings substrate. Significant positive correlations existed between soil microbial biomass C and soil total nitrogen and available phosphorus of C. tora, S. cannabina and C. juncea. In which, soil microbial biomass C (177.56 mg·kg-1) and soil microbial biomass N (9.08 mg·kg-1) of C. juncea MA32 treatment were higher than the content of C. tora and S. cannabina same treatments. Significant negative correlations existed between soil microbial biomass C and soil available Cu (P<0.01), Zn (P<0.05) of C.juncea.(4) Soil urease and dehydrogenase increased of C. tora, S. cannabina and C. juncea after chicken manure amended copper tailings substrate. Significant positive correlations existed between soil urease and dehydrogenase activities and substrate total nitrogen and available phosphorus with growth of S. cannabina and C. juncea, and between soil dehydrogenase activities and soil microbial biomass carbon with growth of C. tora (P<0.05) and C. juncea (P<0.01). Significant negative correlations existed between soil urease (P<0.05) and dehydrogenase (P<0.01) activities and substrate available zinc with growth of C. tora. In which, the soil urease (1.52 NH4+-Nμg·g-1·h-1) was highest of C. juncea MA32 treatment, the soil dehydrogenase (0.26 TPFμg·g-1·d-1) was highest of C. tora MA32 treatment.(5) Acid copper tailings were difficult to the germination of seeds, the seeds of C. juncea can germination in the acid copper tailing substrate after adding lime improved. Biomass were lower of C. juncea after only adding lime amended acid copper tailings substrate, and root showed the appearance of necrosis, and no rhizobium. Used the compound seeds bed can helped to improve the microenvironment of seeds germination (abbreviated for seeds bed), the germination rate of C. juncea increased obviously. Biomass of C. juncea increased significantly after seeds bed amended, and C. juncea had a strong root system, observed obvious nodule.(6)Soil total nitrogen and total phosphorus increased of C. juncea growth substrate after chicken manure and seeds bed amended acid copper tailings substrate. Soil available Cu increased, soil available Zn reduced. Soil microbial biomass C and urease increased of C juncea growth substrate after chicken manure and nutrition lumps amended acid copper tailings substrate. In which, the content of soil microbial biomass C increased to 71.50 mg.kg-1, the content of soil microbial biomass N increased to 15.42 mg.kg-1, soil catalase activity increased to 0.07 (0.1mol·L-1 KMnO4) ml·g-1·h-1, soil urease activity increased to 6.14 NH4+-Nμg·g-1·h-1, soil dehydrogenase activity increased to 9.98 TPFμg·g-1·d-1 in group B treatment after chicken manure amended. In conclusion, These findings indicate that the MA 16 treatment (an amendment rate of 250g tailings to 1g chicken manure) is a suitable method for chicken manure amendment of none acid copper mine tailings. Lime improved pH value and seeds bed promote the plants growth were effective measures to acid copper tailings. C. juncea might be a preferred leguminous species for ecological restoration of copper mine tailings.
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