Root exudates and their ecological consequences in forest ecosystems: Problems and perspective
(2.University of Chinese Academy of Sciences, Beijing, China 100049)
【Abstract】The research on the ecological processes in rhizosphere and the underlying mechanisms has become one of the active and sensitive hotspots in soil science. Root exudates have special roles in mediating the nutrient cycling and signal transduction within root–soil–microorganism interactions. They are the key driving factors regulating the functions of rhizosphere micro-ecosystem, and serve as a major premise for the concept and ecological processes in rhizosphere. However, due to the instinctive advantages of crops, such as short life cycles and convenient operation, the available studies on root exudates mainly focus on agricultural ecosystems and target at providing practical guidelines. In contrast, there have been few investigations on root exudates of trees, which highly limited the knowledge of the potential mechanisms of root exudates in mediating soil biogeochemical processes in forest ecosystems. Based on the main findings in our previous studies and the emerging frontiers in rhizosphere ecology, we specifically reviewed the ecological consequences and key challenges in the research on root exudates in forests. Finally, we put forward several topics and research outlooks for guiding future work to facilitate studies on root exudates and their ecological consequences in forest ecosystems.
【Keywords】 rhizosphere; root exudate; root-soil interactions; soil biogeochemical processes; rhizosphere functional traits; forest;
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