Effect Of Different Amendments On Growth And Cd, Pb Accumulation In Brassia Chinensis

In recent years, with the rapid development of the industry and agriculture, heavy metalpollution has taken a great part of environmental pollution. The heavy metal content of grainand vegetables growing in heavy metal contaminated soil outnumbers the national foodstandards dramatically. It is an extreme threat to people's health when heavy metals enteringhuman bodies through various channels. Therefore, How to effectively reduce the toxicityheavy metals in soils and improve the yields and the quality of crop is indispensable forcontrolling heavy metal pollution and producing unpolluted crops.The study use a potexperiment to observe the yield, the quality of wu-tsai, the content of cadmium and lead aswell as pH of the soil responses to six different kinds of amendments(lime, zeolite, bone mill,FeS2, nano hydroxyapatite and bottom ash) and their combinations applied in heavy metalseverely polluted soil. The study evaluate the effect of applying amendments in heavy metalcontaminated soil to provide the scientific support for ameliorators of soil and harmlesscultivation of vegetable in heavy metal polluted areas. The main results are outlined asfollows:1. The biomass yield of wuta-tsai increased in various degrees after amendmentsapplication. The treatment of zeolite and nano hydroxyapatite co-application showed thehighest yield, which increased the yield by51.1%comparing with no amendmentsapplication. Lime and zeolite co-application can decrease most effectively the Cdconcentrations in the shoot of wuta-tsai, whilst zeolite and bone mill co-application wasefficient at blocking Pb. FeS2and bottom ash co-application can decrease most effectively theCd concentrations in the soil, but the treatment can reduce the Pb concentrations effectively islime and bone mill co-application. This results show that the same amendment on differentmetal resistance control with different results.2. The transport coefficient of cadmium in wuta-tsai was more than the lead, whichexplained cadmium than lead can move to the shoot of the wuta-tsai easily.3. The amendments can improve the soil pH and reduce the availability of heavy metalto reduce the absorption of plants to heavy metal.4. Adding amendments to soil can effectively restrain wu-tsai to absorb cadmium andlead, improving the chlorophyll content of wu-tsai significantly and increase the chlorophylla/b value, promoting them growth and delaying senescence. Meanwhile, the rise of Vc content and the reduce of nitrates and soluble content can sure the quality of wu-tsai.5. The content of cadmium and lead could be reduced in different degrees withamendments application, but the content of heavy metal of wu-tsai planted in cadmium andlead severely polluted soil were still higher than the national food standards.