麻纤维地膜在不同土壤水分条件下的降解特征  

Degradation of the bast fiber mulching film under different soil moisture conditions

作　　者：龙世方 朱奇宏[2] 周建利[1] 黄道友[2] 刘波[1,2] 吕光辉 段明梦 LONG Shi-fang;ZHU Qi-hong;ZHOU Jian-li;HUANG Dao-you;LIU Bo;Lu Guang-hui;DUAN Ming-meng(College of Agriculture, Yangtze University, Jingzhou, Hubei 434025, China;Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture,Chinese Academy of Sciences, Changsha, Hunan 410125, China)

机构地区：[1]长江大学农学院,湖北荆州434025 [2]中国科学院亚热带农业生态研究所亚热带农业生态过程重点实验室,湖南长沙410125

出　　处：《农业现代化研究》2019年第2期349-356,共8页Research of Agricultural Modernization

基　　金：国家麻类产业技术体系建设专项(CARS-16-E09);湖湘青年英才(2017RS3057)~~

摘　　要："白色污染"问题催生了麻纤维地膜等可降解地膜的研发,其在不同土壤水分等环境条件下的降解特征与应用前景密切相关。为此,采用盆钵埋袋试验,结合扫描电镜(SEM)和傅里叶红外光谱(FTIR)技术,分析麻纤维地膜在土壤含水量为15%、25%和淹水条件下的降解特征,并探讨其与土壤微生物及酶活性的关系。结果表明,麻纤维地膜的降解过程均服从Olson衰减模型(P <0.01),15%、25%土壤含水量和淹水条件下,其半降解时间依次为124 d,50 d和69 d。在供试土壤水分条件下,同等降解率的地膜SEM图像和FTIR图谱无明显差异。SEM图像显示,随着麻纤维地膜降解程度的加剧,其表面微观结构呈现褶皱—褶皱/裂缝—褶皱/孔洞的变化过程。依据FTIR图谱在麻纤维地膜降解率达到40%时(25%土壤水分条件下降解30 d)出现的C=O特征峰,可推断其降解过程为纤维素断链,形成具有C=O键的直链式葡萄糖。试验末期,各水分处理的麻纤维地膜降解率与土壤微生物生物量变化规律一致,说明土壤水分条件导致的土壤微生物生物量变化,可能是影响麻纤维地膜降解速率差异的原因之一。The degradable films, such as bast fiber mulch film(BFMF), have been rapidly developed in recent years to deal with the white pollution. While, the application of such films might be controlled by their degradation characteristics under different environmental conditions. Therefore, the degradation characteristics of BFMF and its relationship with microbial biomass and enzyme activities under soil moisture contents of 15%, 25% and flooding conditions were investigated by a bag-buried pot experiment. The scanning electron microscope(SEM) and fourier transform infrared spectroscopy(FTIR) were used in the experiment. The results indicated that the degradation processes of BFMF followed the Olson attenuation model(P < 0.01). Due to the model, the semi-degradation time of BFMF under the conditions of 15% and 25% soil moisture content and flooding was approximately 124, 50 and 69 d,respectively. There was no significant difference in SEM images and FTIR spectrum at the same degradation rate under the three soil moisture conditions. Based on the SEM results, the surface structure of BFMF during degradation process was as wrinkles-folds/cracks-folds/pores. The FTIR spectrum showed that the main component of the BFMF was cellulose and the C=O characteristic peak appearance when the degradation rate reached to 40%(degradation at 30 d under 25% of soil water content). The results of FTIR analysis might indicate that the degradation process of the BFMF was concluded to be cellulose broken chain, forming a straight chain glucose with C=O bond. Moreover, the degradation rates of BFMF of each water treatment were consistent with the changes of soil microbial biomass at the end of the experiment, which indicated that the microbial biomass changes caused by soil moisture conditions may be the reason for influencing the degradation rate of BFMF.

关 键 词：麻纤维地膜 土壤水分 降解特征 扫描电镜 傅里叶红外光谱 

分 类 号：S563[农业科学—作物学]