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【Objective】In order to provide scientific basis for the optimization of intercropping patterns and the management of intercropping under rubber plantations in the future, the effects of different intercropping patterns on the functional diversity of soil microbial communities in mature rubber plantations were studied. 【Method】Biolog-ECO technology was used to study the characteristics of soil microbial functional diversity, and the differences of soil microbial metabolic activity and diversity on carbon sources in different intercropping plantations were analyzed. 【Result】Soil microbial carbon utilization was stable at 216 hours, and the average light absorption value AWCD of different treatments was in the order of rubber-kinggrass intercropping＞rubber-coffee intercropping＞rubber-puzzle intercropping＞rubber.The intercropping pattern not only increased the types of carbon sources utilized by soil microorganisms, but also enhanced the metabolic activity of carbon sources.The metabolic capacity of soil microorganisms to carbohydrates, amino acids, phenolic acids, carboxylic acids and polymers was the strongest in rubber-kinggrass intercropping, and the metabolic capacity of amines was the strongest in rubber-coffee intercropping.There were significant differences in soil microbial carbon source utilization between intercropping patterns and rubber plantation by PCA （principal component analysis), significant differences between rubber-kinggrass and rubber-coffee, rubber-puzzle, but no significant differences between rubber-coffee and rubber-puzzle intercropping.The research showed that different intercropping modes could improve the soil microbial diversity index, and there were significant differences in AWCD value and McIntosh index among different treatments, but no significant differences in Shannon index and Simpson index.Correlation analysis showed that the metabolic function of soil microbial carbon source was closely related to soil environmental factors, and soil water content, pH and organic matter were the main factors affecting the differences of soil carbon source metabolism. 【Conclusion】Intercropping for kinggrass, puzzle and coffee can improve soil ecological environment, promote the utilization of soil carbon sources, and enhance the functional diversity of soil microbial community in rubber plantation. [ABSTRACT FROM AUTHOR]

【Objective】 This study was conducted to explore the characteristics of soil physial chemical and microbes properties, and their correlation relationships with four different soil parent materials （granite, basalt, metamorphic rock and shallow marine deposit） from rubber plantations in Hainan Island to provide the basis for soil quality management. 【Method】 By means of investigation and sampling, correlation analysis, redundancy analysis and other statistical methods, 13 physical and chemical indexes, such as soil water content, organic carbon, microbial carbon and other microbial indexes of rubber plantation under different parent material conditions were studied. 【Result】 There were significant differences in soil physicochemical properties and soil microbial community among different soil parent materials from rubber plantations, and the basalt was superior to the others three parent materials. The comprehensive comparison of soil fertility was as follows as basalt（1.90）> shallow sea sediment（1.88）> metamorphic rock（1.59）> granite（-5.37）. The soil MBN, MBC, water content and soil temperature were main influencing factors for soil fertility in different parent materials by PCA （principal component analysis）. In addition, soil microbes was significantly correlated with the physical and chemical properties, which of main factors were soil water content, pH, total potassium, temperature, total phosphorus and available nitrogen by RDA （redundancy analysis）. 【Conclusion】 The above results suggested that there was very close relationship between soil microbes and soil physicochemical properties, and different impact factors for soil fertility among different typical parent materials. Therefore, the variation characteristics and relationship between soil microbes with soil physicochemical properties in the research process of evaluation and management of soil quality in rubber plantation under different parent materials and other farming conditions must be considered in rubber plantations. [ABSTRACT FROM AUTHOR]