绿海石粉在堆肥过程中的降解及其对微生物群落结构变化的影响

Effect of Potassium Mineral on Microbial Community Structure of Composting and Its Degradation

利用堆肥所具有的降解特性和很高的解钾能力,将堆肥中加入的钾矿粉(绿海石粉)分解为植物能够吸收的有效钾,并用PLFA方法评价了绿海石粉对堆肥中微生物群落结构的影响。结果表明,通过堆肥,从绿海石中降解出的有效钾逐渐增高,到堆肥后期可达到1650mg·kg-1。部分不饱和脂肪酸(PLFA18:2)、环丙烷脂肪酸(cy17:0,cy19:0)、含10Me的脂肪酸(10Me16:0,10Me17:0)含量有较大的变化,相应的真菌、革兰氏阴性细菌和放线菌有明显的增加,这说明堆肥中加入绿海石粉对微生物群落结构变化产生了影响,成为堆肥解钾的理论依据。PLFA法可用于快速检测微生物群落的变化,是一种理想的分子生态学方法。

Composting is a complicate reaction system, in which series of biochemistry reaction have happened and microbial community structure has changed. Through composting, potassium mineral will be decomposed into to soluble potassium that can be absorbed by plants. This study aimed to investigate the potassium mineral degradation through composting and its effects on microbial community structure. Two composting piles were conducted （one pile is added the potassium mineral, and the other pile is the control）. Phospholipid fatty acid （PLFA） method was used to estimate the microbial community structure changes during composting. The results indicated that the amount of soluble potassium which dissolving from potassium mineral drastically increased in the final phase of composting, and reached 1 650 mg·kg^-1. The rapid increase in temperature was 2 days later, and pH was decelerated to 5.0. Microbial community structure was also obviously influenced by potassium mineral added to composting. In the initial phase, the activity and growth of mesophilicorganisms were slower than those of control. But in the high temperature period, they quickly increased. Moreover, the number of microbial community such as fungi, Gramnegative bacterium and Actinomyces increased quickly in the process of dissolving stage. Some PLFAs, such as 18：2, 10Mel6：0, 10Me 17：0, 10Me 18：0, cy 17：0, cy 19：0, have been greatly changed with the appearance of potassium dissolving capacity. The results show that PLFA is an ideal method to analysis the microbial community structure during the composting.