Institution
University System of Maryland
Education•Adelphi, Maryland, United States•
About: University System of Maryland is a education organization based out in Adelphi, Maryland, United States. It is known for research contribution in the topics: Water column & Bay. The organization has 286 authors who have published 273 publications receiving 14621 citations. The organization is also known as: USM.
Topics: Water column, Bay, Ascendency, Ecosystem, Higher education
Papers published on a yearly basis
Papers
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TL;DR: The biomass and production of seagrass populations were reassessed based on the compilation of a large data set comprising estimates for 30 species, derived from the literature, indicating a general tendency for a balanced distribution of biomass between leaves and rhizomes + roots.
750 citations
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TL;DR: In this paper, the authors assemble and analyze quantitative annual input-export budgets for total nitrogen (TN) and total phosphorus (TP) for Chesapeake Bay and three of its tributary estuaries (Potomac, Patuxent, and Choptank rivers).
Abstract: In this paper we assemble and analyze quantitative annual input-export budgets for total nitrogen (TN) and total phosphorus (TP) for Chesapeake Bay and three of its tributary estuaries (Potomac, Patuxent, and Choptank rivers). The budgets include estimates of TN and TP sources (point, diffuse, and atmospheric), internal losses (burial in sediments, fisheries yields, and denitrification), storages in the water column and sediments, internal cycling rates (zooplankton excretion and net sediment-water flux), and net downstream exchange. Annual terrestrial and atmospheric inputs (average of 1985 and 1986 data) of TN and TP ranged from 4.3 g TN m−2 yr−1 to 29.3 g TN m−2 yr−1 and 0.32 g TP m−2 yr−1 to 2.42 g TP m−2 yr−1, respectively. These rates of TN and TP input represent 6-fold to 8-fold and 13-fold to 24-fold increases in loads to these systems since the precolonial period. A recent 11-yr record for the Susquehanna River indicates that annual loads of TN and TP have varied by about 2-fold and 4-fold, respectively. TN inputs increased and TP inputs decreased during the 11-yr period. The relative importance of nutrient sources varied among these estuaries: point sources of nutrients delivered about half the annual TN and TP load to the Patuxent and nearly 60% of TP inputs to the Choptank; diffuse sources contributed 60–70% of the TN and TP inputs to the mainstream Chesapeake and Potomac River. The direct deposition of atmospheric wet-fall to the surface waters of these estuaries represented 12% or less of annual TN and TP loads except in the Choptank River (37% of TN and 20% of TP). We found direct, although damped, relationships between annual rates of nutrient input, water-column and sediment nutrient stocks, and nutrient losses via burial in sediments and denitrification. Our budgets indicate that the annual mass balance of TN and TP is maintained by a net landward exchange of TP and, with one exception (Choptank River), a net seaward transport of TN. The budgets for all systems revealed that inorganic nutrients entering these estuaries from terrestrial and atmospheric sources are rapidly converted to particulate and organic forms. Discrepancies between our budgets and others in the literature were resolved by the inclusion of sediments derived from shoreline erosion. The greatest potential for errors in our budgets can be attributed to the absence of or uncertainties in estimates of atmospheric dry-fall, contributions of nutrients via groundwater, and the sedimentation rates used to calculate nutrient burial rates.
602 citations
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TL;DR: Verification studies support the use of otolith microchemistry to measure migratory schedules and habitat utilization patterns in anadromous striped bass populations.
380 citations
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TL;DR: Stabilization of recruitments through density-dependent growth rate variability in early life is demonstrated to be potentially important and whether this mechanism actually is important in the sea remains to be determined.
Abstract: Fluctuations in the abundance of fishes may be caused by episodic mortalities or by more subtle variability in the daily growth and mortality rates of eggs and larvae. Survival response surfaces are used to illustrate the relative effects of episodic and subtle mortality during early life. It is the subtle variability associated with small changes in growth or mortality rates that may exert the greater effect on recruitment. Massive advective losses of eggs or larvae, failed egg production, and acute contaminant mortalities are examples of episodic events that may impact recruitment significantly but which need not be catastrophic. Stabilization of recruitments through density-dependent growth rate variability in early life is demonstrated to be potentially important. Whether this mechanism actually is important in the sea remains to be determined.
356 citations
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TL;DR: A series of oxic and anoxic incubations examined the decay of two marine phytoplankton, the diatom Thalassiosira weissffogii and the coccoid cyanobacterium Synechococcus sp, in flow-through systems without macrozooplankton grazers.
326 citations
Authors
Showing all 286 results
Name | H-index | Papers | Citations |
---|---|---|---|
Rita R. Colwell | 115 | 781 | 55229 |
Robert Costanza | 114 | 494 | 80285 |
Yves F. Dufrêne | 82 | 315 | 20046 |
Robert P. Mason | 79 | 230 | 22515 |
Daniel J. Conley | 74 | 211 | 20144 |
Douglas G. Capone | 74 | 212 | 24134 |
Patricia M. Glibert | 70 | 212 | 19944 |
Thomas M. Antonsen | 65 | 888 | 17583 |
Eric E. Roden | 65 | 162 | 13628 |
Diane K. Stoecker | 61 | 136 | 13150 |
Robert E. Ulanowicz | 54 | 178 | 11888 |
David H. Secor | 51 | 174 | 10190 |
Walter R. Boynton | 48 | 83 | 10561 |
Shiladitya DasSarma | 48 | 135 | 6813 |
Nima Hafezi-Nejad | 47 | 133 | 72925 |