Soil properties and enzyme activities regulate the changes of soil microbial communities alongside Pandanus amaryllifolius Roxb. intercropping with Areca catechu L. plantation in a tropical islands of China
Description
The intercropping pattern promote the sustainable development of efficient agriculture by accelerating soil nutrients activation, ameliorating soil properties, and improving ecosystem productivity, especially cash crops, such as Areca catechu L. (Ac) and Pandanus amaryllifolius Roxb. (Pa) intercropping plantation in tropical island of China. However, the mechanisms underlying intercropping pattern effects on soil microbial community diversity and composition are poorly understood. Therefore, a field experiment with three cultivated patterns of Areca catechu L. monoculture (A), Pandanus amaryllifolius Roxb. monoculture (P), and Areca catechu L. intercropping with Pandanus amaryllifolius Roxb. (I) was established to exploring the regulation mechanism of soil microbial community under intercropping pattern by monitoring the changes of soil physicochemical properties, enzyme activities, microbial (bacterial and fungal) diversity and composition. The results show that the soil nutrient content and enzyme activity are significantly decreased with significant correlations being observed. Soil bacterial rather than fungal communities diversity are more sensitive to intercropping pattern. The significant decrease of soil bacterial diversity by 4.21% in Areca catechu L. monoculture plantation after intercropping with Pandanus amaryllifolius Roxb. may attribute to the reduction of soil organic matter, potassium content and the inhibition of polyphenol oxidase and urease activities. The changes in the relative numbers of specific taxa, especially Gemmatimonadota and Myxococcota are regulated by soil pH, moisture, potassium content and urease activity, although the dominant bacterial Proteobacteria, Acidobacteria, Actinobacteria, Chloroflexi and Firmicutes do not respond to the intercropping pattern. Overall, the decrease of soil nutrient content may be the main reason for the change of soil enzyme activity, bacterial community diversity and composition structure under intercropping pattern. Supplementing nutrients to the soil of intercropping systems is conducive to maintain soil health and ecosystem functional stability in the tropical compound cultivation plantation.