ZHOU Jiajia1, LUO Youfa1, MA Lirong1, XING Rongrong1, WU Yonggui1,2,3
(1.College of Resources and Environmental Engineering, Guizhou University, Guiyang 550025, China;
2.Karst Eco-Environmental Engineering Research Center of Guizhou Province, Guiyang 550025, China;
3.Graduate Workstation of Environmental Functional Material and Equipment Research and Development, Guizhou Province, Guiyang 550025, China)
Abstract: The study aimed to investigate the plant internal stability and the relationship between vegetation type and restriction of nitrogen and phosphorus in the waste slag-plant system of revegetated zinc smelting waste slag yards, a zinc smelting waste slag yard, which had been revegetated plants for 4 years in Monkey Town, Weining County, northwestern Guizhou, was selected as the study area, and five dominant plants (Broussonetia papyrifera, Cryptomeria fortunei, Buddleja davidii, Arundo donax, Trifolium repens L), which grew well at the waste slag yard, were selected as the study objects. The eco-stoichiometric characteristics of carbon (C), nitrogen (N), phosphorus (P) and potassium (K) in these five dominant plants at the zinc smelting waste slag yard were studied. The results showed that contents of C and N in waste residues repaired by different dominant plants were relatively higher, while contents of P and K were relatively lower. The contents of N and P were significantly higher in slags restored by Trifolium repens L than by other plants (p<0.05). The available contents of N, P and K were higher in slags restored by Trifolium repens L, and lower in slags restored by Broussonetia papyrifera. The stoichiometric characteristics of elements were C:P>C:K>C:N>N:P>N:K>P:K. The N:K and P:K ratios were significantly higher in slags restored by Trifolium repens L than by other four plants. The N content was lower overall. The contents of N, P and K were significantly higher in Trifolium repens L than in other plants. The N:P ratio in leaves indicated that the plant growth was restricted by N except Trifolium repens L which was restricted by P. The correlations among nutrients in waste slags and in plant leaves indicated that contents of N, P and K in leaves significantly and positively correlated with their availabilities in slags (p<0.05), and that, except the ratio of N:P in leaves which was positively correlated with the available contents of nutrient (N, P, and K), stoichiometric ratios of nutrient elements in leaves were negatively correlated with the available contents of nutrients (N, P and K), specially ratios of C:K and P:K in leaves which were negatively correlated with the available contents of nutrients (N, P, and K) very significantly (p<0.01). Therefore, we concluded that contents of nutrients (N, P and K) and their ecological stoichiometry in plant leaves were affected significantly by available contents of nutrients in waste slags of the study site.
Key words: zinc smelting waste slag; phytoremediation; plant leaves; nutrients; eco-stoichiometry
EARTH AND ENVIRONMENT Vol.47, No.4, Tot No.330, 2019, Page 419-428