Study On Applying Sewage Sludge To Petunia Hyhrida Vilm Planting

This article use the Qingshanhu Sewage treatment plant sludge as the matrix planter ornamental plant—Petunia hyhrida Vilm, exploring from gardens value angle embarking,practices regarding the sludge reasonable use. Research under the different sludge exerts the quantity, Petunia hyhrida Vilm' growth situation and the rule of heavy metal concentrates,and sludge using in gardens bring environmental influence. The hope realizes by this reduces processes the urban sludge the cost,simultaneously can have certain economic efficiency goal,and provide gist for urban sludge use.This article on the basic of analyse the Qingshanhu Sewage treatment plant sludge's basic character,use different volume proportion of sludge compose to wood chips,cinder, designed under six different processing and one comparison:sludge, sawdust, cinder (1:1: 1),(2:2:1),(2:1:1),(3:1:1),(3:2),(3:2); the comparison:garden soil. Six different processing after composted, potted plant experimentation,by stated growth cycle, mensurate Zn,Cu,Cd,Pb,Cr content and Petunia hyhrida Vilm's growth status index.Via lixiviate experimentation, and potted plant experimentation, discuss under different processing's sludge employment quantity to environmental's influence,and using in garden's feasibility. The main experimental results and conclusions as follows:(1) Raw sewage sludge and wood chips, cinder, after composting, the different soil compared with garden soil,available N, P, K and organic matter content, all increased significantly, indicating that the sludge can improve fertility of the soil. And heavy metals in the soil will be imposed as the sludge increases, but none more than "municipal wastewater treatment plant sludge disposal landscape with mud" (CJ248-2007) standard limit. And through the analysis of coefficient of variation, that variation of soil is very rich in many traits, can through the addition of appropriate amount of sludge makes these traits with varying degrees of increase. Through the correlation analysis, we know that many traits in soil exists the relations of mutual restraint, in order to make the best comprehensive properties of the soil, no other than to reach a certain balance.(2) By monitoring the growth of Petunia hybrida showed that the amount of sewage sludge composting and petunia growth exist dose-response relationship. In a growth period, development of petunia in the soil 3 was the best. When petunia planted in the soil 4, its growth was inhibited. Meanwhile, the CK group, lack of nutrients, lead poor growing. And through the correlation analysis shows that petunia growth and available N, available P, available K in sludge were significantly correlated. (3) Heavy metals Zn and Cu accumulation in plants is relatively routine, with the the amount of sludge increased, the amount of enrichment in petunia body also increased, and the difference is significant. For Cd, Pb and Cr, with the amount of sludge increased, the amount of enrichment in petunia body also increased, but the amount of sludge applied the volume occupied by more than 50%, the enrichment capacity to the limit. Through count enrichment coefficient, petunia obtained Zn was best, but the petunias to different heavy metals Cu, Zn, Cr, Pb, Cd accumulation ability was not prominence.(4) After the soil plant petunia, the soil with the amount of sludge applied increased,heavy metals in the residue increased, but in line with "soil environmental quality standard" (GB15618-1995) in Grade III. Through the residual rate counted, we know that Pb, Cd and Cr was significantly higher than Cu and Zn. And the garden soil on the metal Pb, Cd and Cr's residues rate was the highest. In addition to the comparison, with the content of municipal sewage sludge in soil increased, the soil in the residual rate of metal Zn and Cu decreased. Pb, Cd and Cr of the residual rate is not entirely content with the changes to add, but when the content of the soil in the largest quantity of sludge, the residual rate was the highest. And through the correlation analysis shows that, the correlation of Pb, Cu, Zn, Cr, Cd residues in the soil is more prominence, indicating that there are several elements exist complex pollution.Leaching experiment results show that the leaching out heavy metal's concentration increased, with the addition of sewage sludge increased, but all were below the leaching out toxicity standard of "Identification standard for hazardous wastes-Leaching Toxicity identification" (GB5085.3-1996), the environment little impacted. Obtained by leaching rate, we can see that the use of city sludge in gardens, descending order of heavy metal potential pollution on the environment,for the Cu>Zn>Pb>Cr>Cd.