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The scientific community has voiced two general concerns about the future of the earth. Climatologists and oceanographers have focused on the changes in our physical environment -- changes in the climate, the oceans, and the chemistry of the air we breathe. Environmental biologists, on the other hand, have addressed issues of conservation and the extinction of species. There is increasing evidence that these two broad concerns are intertwined and mutually dependent. Past changes in biodiversity have both responded to and caused changes in Earth's environment. In its discussions of ten key terrestrial biomes and freshwater ecosystems, this volume uses our broad understanding of global environmental change to present the first comprehensive scenarios of biodiversity for the twenty-first century. Combining physical earth science with conservation biology, Future Scenarios of Global Biodiversity provides a starting point for regional assessments on all scales. The book will be of interest to those concerned with guiding research on the changing environment of the earth and with planning future policy, especially in accordance with the Global Biodiversity Convention

Ecology at the ecosystem level has both necessitated and benefited from new methods and technologies as well as those adapted from other disciplines. With the ascendancy of ecosystem science and management, the need has arisen for a comprehensive treatment of techniques used in this rapidly-growing field. Methods in Ecosystem Science answers that need by synthesizing the advantages, disadvantages and tradeoffs associated with the most commonly used techniques in both aquatic and terrestrial research. The book is divided into sections addressing carbon and energy dynamics, nutrient and water dynamics, manipulative ecosystem experiements and tools to synthesize our understanding of ecosystems. Detailed information about various methods will help researchers choose the most appropriate methods for their particular studies. Prominent scientists discuss how tools from a variety of disciplines can be used in ecosystem science at different scales

Belowground organisms play critical roles in maintaining multiple ecosystem processes, including plant productivity, decomposition, and nutrient cycling. Despite their importance, however, we have a limited understanding of how and why belowground biodiversity (bacteria, fungi, protists, and invertebrates) may change as soils develop over centuries to millennia (pedogenesis). Moreover, it is unclear whether belowground biodiversity changes during pedogenesis are similar to the patterns observed for aboveground plant diversity. Here we evaluated the roles of resource availability, nutrient stoichiometry, and soil abiotic factors in driving belowground biodiversity across 16 soil chronosequences (from centuries to millennia) spanning a wide range of globally distributed ecosystem types. Changes in belowground biodiversity during pedogenesis followed two main patterns. In lower-productivity ecosystems (i.e., drier and colder), increases in belowground biodiversity tracked increases in plant cover. In more productive ecosystems (i.e., wetter and warmer), increased acidification during pedogenesis was associated with declines in belowground biodiversity. Changes in the diversity of bacteria, fungi, protists, and invertebrates with pedogenesis were strongly and positively correlated worldwide, highlighting that belowground biodiversity shares similar ecological drivers as soils and ecosystems develop. In general, temporal changes in aboveground plant diversity and belowground biodiversity were not correlated, challenging the common perception that belowground biodiversity should follow similar patterns to those of plant diversity during ecosystem development. Taken together, our findings provide evidence that ecological patterns in belowground biodiversity are predictable across major globally distributed ecosystem types and suggest that shifts in plant cover and soil acidification during ecosystem development are associated with changes in belowground biodiversity over centuries to millennia. ; European Union's Horizon 2020 research and innovation program under Marie Sklodowska-Curie Grant [702057]; US National Science FoundationNational Science Foundation (NSF) [EAR1331828, DEB 1556090] ; This project received funding from the European Union's Horizon 2020 research and innovation program under Marie Sklodowska-Curie Grant Agreement 702057. N.F. was supported through grants from the US National Science Foundation (EAR1331828, DEB 1556090). Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the US Government. An extended version of the acknowledgments is provided in SI Appendix. ; Public domain authored by a U.S. government employee