Project description:Multi-species interactions are a major force in the evolution and dynamics of ecosystems. These interactions may occur either when species affect each other directly or when they interact indirectly via an intermediary species. Direct interactions between species are best understood, but indirect interactions may also often be strong enough to alter the evolutionary trajectories of the target species. Little is known about the genetic basis of direct interactions within an ecosystem and even less data is available for indirect interactions. This experiment uses a simple model ecosystem to build a view at the transcriptome level of how interactions between plants (Arabidopsis) and rhizosphere bacteria (Pseudomonas) are altered by biotic stressors (insect herbivores) and abiotic stressors (UV-B). Keywords: stress response
2008-11-25 | GSE4973 | GEO
Project description:studies of mercury on ecosystem multifunctionality
Project description:Understanding the biogeographical patterns and underlying drivers of microbial functional diversity is essential for anticipating climate change impacts on ecosystem functioning worldwide. However, this matter remains scarcely addressed in freshwater ecosystems. Using the high-throughput gene array GeoChip 4.0, we show that functional gene alpha diversity and compositon differ across mountains, alpha diversity declines towards high elevations and compositional turnover increases with larger elevational distances. Both continental- and mountain-scale patterns were primarily driven by climatic variables.
Project description:Global warming substantially changes precipitation patterns in the Tibetan plateau, with projection of increased precipitation in southern and northern Tibet but decreased precipitation in the center. Understanding mechanisms of such changes in greenhouse gas emissions is of vital importance in predicting ecosystem feedbacks to climate changes. Nonetheless, it has been hampered by limited knowledge in soil microbial communities, one of the major drivers of greenhouse gas emission. Here, we report a field experiment simulating drying and wetting conditions in the Tibetan grassland. Our field site is located at the Haibei Alpine Grassland Ecosystem Research Station in the northeast of Tibet Plateau, China, and we employed GeoChip 5.0 180K to analyze microbial responses. 18 samples were collected from 3 plots in Haibei Station, with 6 replicates in each plot