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Dissolved organic carbon (DOC), lignin biomarkers, and the optical properties of dissolved organic matter (DOM) were measured in the Epulu River (northeast Democratic Republic of Congo) with the aim of investigating temporal controls on the quantity and chemical composition of DOM in a tropical rainforest river. Three different periods defined by stages of the hydrologic regime of the region, (1) post dry flushing period, (2) intermediary period, and (3) start of the dry period/post flush, were sampled. Temporal variability in DOM quantity and quality was observed with highest DOC, lignin concentration (Σ8) and carbon‐normalized (Λ8) values during the flushing period attributed to greater surface runoff and leaching of organic‐rich horizons, with lowest values in the dry period/post flush once source materials were well leached. Chromophoric DOM (CDOM) was strongly correlated to DOC and Σ8 (r2 = 0.85 and 0.83, respectively; p < 0.001), and CDOM quality measurements (SUVA254, spectral slope ratio and fluorescence index) were strongly correlated to Λ8 values (r2 = 0.77, 0.69, and 0.75, respectively; p < 0.001), demonstrating the ability to derive DOC and lignin export and to track DOM quality in tropical riverine systems from simple optical measurements. This study demonstrates similar effects in the variability of DOM quantity and quality due to changing hydrologic inputs for a tropical river as has been previously reported for temperate and northern high‐latitude rivers. Therefore, flushing periods in tropical rivers warrant further study, as they are critical toward understanding ecosystem biogeochemistry as maximal export of freshly leached plant material occurs during this time period.

A comprehensive cross-biome assessment of major nitrogen (N) species that includes dissolved organic N (DON) is central to understanding interactions between inorganic nutrients and organic matter in running waters. Here, we synthesize stream water N chemistry across biomes and find that the composition of the dissolved N pool shifts from highly heterogeneous to primarily comprised of inorganic N, in tandem with dissolved organic matter (DOM) becoming more N-rich, in response to nutrient enrichment from human disturbances. We identify two critical thresholds of total dissolved N (TDN) concentrations where the proportions of organic and inorganic N shift. With low TDN concentrations (0-1.3 mg/L N), the dominant form of N is highly variable, and DON ranges from 0% to 100% of TDN. At TDN concentrations above 2.8 mg/L, inorganic N dominates the N pool and DON rarely exceeds 25% of TDN. This transition to inorganic N dominance coincides with a shift in the stoichiometry of the DOM pool, where DOM becomes progressively enriched in N and DON concentrations are less tightly associated with concentrations of dissolved organic carbon (DOC). This shift in DOM stoichiometry (defined as DOC:DON ratios) suggests that fundamental changes in the biogeochemical cycles of C and N in freshwater ecosystems are occurring across the globe as human activity alters inorganic N and DOM sources and availability. Alterations to DOM stoichiometry are likely to have important implications for both the fate of DOM and its role as a source of N as it is transported downstream to the coastal ocean. ; National Science Foundation (NSF) through the Long-Term Ecological Research Network Office (LNO), National Center for Ecological Analysis and Synthesis (NCEAS), University of California-Santa Barbara [1545288]; NSFNational Science Foundation (NSF) [1556603]; New Hampshire Agricultural Experiment Station; USDA National Institute of Food and Agriculture McIntire-Stennis Project [1006760, 1016163]; Natural Environment Research Council, UK Large Grant [NE/K010689/1] ; Published version ; This work was conducted as a part of the Stream Elemental Cycling Synthesis Group funded by the National Science Foundation (NSF) under grant DEB#1545288, through the Long-Term Ecological Research Network Office (LNO), National Center for Ecological Analysis and Synthesis (NCEAS), University of California-Santa Barbara. The authors acknowledge the efforts of Julien Brun for assistance with data synthesis and the efforts of multiple individuals who collected and analyzed samples. Partial support for ASW during data synthesis and manuscript preparation was provided by NSF grant DEB#1556603 (Deciphering Dissolved Organic Nitrogen). Partial funding was provided by the New Hampshire Agricultural Experiment Station. This is Scientific Contribution 2880. This work was supported by the USDA National Institute of Food and Agriculture McIntire-Stennis Project 1006760. Support for AA was provided by the USDA National Institute of Food and Agriculture McIntire-Stennis Project 1016163. Partial support for PJJ and CAY was provided by Natural Environment Research Council, UK Large Grant NE/K010689/1 (DOMAINE: Characterizing the Nature, Origins and Ecological Significance of DOM in Freshwater Ecosystems). The authors are also grateful for feedback from two anonymous reviewers whose comments significantly improved this manuscript. This paper is dedicated to the memory of Dr. John Schade, a friend, colleague, and mentor to many of us. John studied ecological stoichiometry in freshwater ecosystems and led the Long-Term Ecological Research (LTER) group at the US National Science Foundation. ; Public domain authored by a U.S. government employee

Edward W. Said (1935–2003) ranks as one of the most preeminent public intellectuals of our time. Through his literary criticism, his advocacy for the Palestinian cause, and his groundbreaking book Orientalism, Said elegantly enriched public discourse by unsettling the status quo. This indispensable volume, the most comprehensive and wide-ranging resource on Edward Said's life and work, spans his broad legacy both within and beyond the academy. The book brings together contributions from thirty-one luminaries—leading scholars, critics, writers, and activists—to engage Said's provocative ideas. Their essays and interviews explore the key themes of emancipation and representation through the prisms of postcolonial theory, literature, music, philosophy, and cultural studies.Contributors: Bill Ashcroft, Ben Conisbee Baer, Daniel Barenboim, Timothy Brennan, Noam Chomsky, Denise DeCaires-Narain, Nicholas Dirks, Marc H. Ellis, Rokus de Groot, Sabry Hafez, Abdirahman A. Hussein, Ardi Imseis, Adel Iskandar, Ghada Karmi, Katherine Callen King, Joseph Massad, W. J. T. Mitchell, Laura Nader, Ilan Pappe, Benita Parry, Rajagopalan Radhakrishnan, Jahan Ramazani, Jacqueline Rose, Lecia Rosenthal, Hakem Rustom, Avi Shlaim, Ella Habiba Shohat, Robert Spencer, Gayatri Chakravorty Spivak, Anastasia Valassopoulos, Asha Varadharajan, Michael Wood