Abstract：
Pyrolyzing and returning to farmland is one of the potential methods for farmland plastic film waste. This study explored both pyrolyzation and activation optimum conditions of a mixture of plastic film (polyethylene) and maize straw (MPS) in a 1:5 ratio to produce MPS-char, investigated the action of the char on the maize seedling stage (for 30 days). The results showed that the char promoted the root to be more advanced than aboveground part, therefore, this study experimentally clarified the role MPS-char played when added to the soil. The functional groups of the char were varied by the participation of polyethylene. Carbon-based groups were observed, such as carbonyl or carboxyl groups, which could constitute an NH4+ absorption release system to increase the existence of urea in soil, therefore the average nitrogen concentration was improved by 16.18 %. However, the shallow soil temperature increased by 2.03 °C, and the deep soil temperature slightly decreased with the effect of MPS-char. While, the soil moisture content was slightly reduced in the second half of the experiment, and the soil oxygen content increased by 7.64 % throughout the whole experiment. Overall, returning MPS-char to farmland showed a positive effect on maize growth, which was caused by the variation of both chemical and physical properties. This variation provides opportunities for further promotion of rhizosphere development.
摘要：
热解还田是处理农田地膜废弃物的潜在方法之一。这项研究探索了以1：5比例生产MPS-炭的塑料薄膜（聚乙烯）和玉米秸秆（MPS）混合物的热解和活化最佳条件，研究了炭素对玉米苗期(30天)的作用。结果表明，炭素促进根系比地上部分更先进，因此,这项研究通过实验阐明了添加到土壤中时MPS-char所起的作用。焦炭的官能团因聚乙烯的参与而变化。观察到碳基基团，如羰基或羧基，可以构成NH4+吸收释放系统，增加土壤中尿素的存在，因此平均氮浓度提高了16.18%。然而,浅层土壤温度增加了2.03°C，深层土壤温度在MPS-char的作用下略有下降。同时,在实验的后半部分，土壤水分含量略有降低，在整个实验过程中，土壤氧含量增加了7.64％。总的来说,MPS-char退耕对玉米生长有积极影响，这是由化学和物理性质的变化引起的。这种变化为进一步促进根际发育提供了机会。
