A5079580464- Marine and coastal ecosystems
- Aquatic Ecosystems and Phytoplankton Dynamics
- Marine Biology and Ecology Research
- Soil and Water Nutrient Dynamics
- Marine and coastal plant biology
- Coastal wetland ecosystem dynamics
- Marine Bivalve and Aquaculture Studies
- Wastewater Treatment and Nitrogen Removal
- Microbial Community Ecology and Physiology
- Soil Carbon and Nitrogen Dynamics
- Geochemistry and Elemental Analysis
- Mine drainage and remediation techniques
- Peatlands and Wetlands Ecology
- Marine and fisheries research
- Phosphorus and nutrient management
- Hydrology and Watershed Management Studies
- Oceanographic and Atmospheric Processes
- Fish Ecology and Management Studies
- Atmospheric chemistry and aerosols
- Groundwater and Isotope Geochemistry
- Odor and Emission Control Technologies
- Air Quality Monitoring and Forecasting
- Ocean Acidification Effects and Responses
- Food Industry and Aquatic Biology
- Iron oxide chemistry and applications
Cornell University
2013-2024
Marine Biological Laboratory
2003-2021
The first special volume of Limnology and Oceanography, published in 1972, focused on whether phosphorus (P) or carbon (C) is the major agent causing eutrophication aquatic ecosystems. Only slight mention was made that estuaries may behave differently from lakes nitrogen (N) cause estuaries. In following decade, an understanding proceeded relative isolation community scientists studying lakes. National water quality policy United States directed almost solely toward P control for both...
Planktonic nitrogen fixation in lakes is strongly related to lake trophic status, with moderate and high rates usually occurring only eutrophic lakes. Among lakes, the ratio of loading phosphorus lake; significant by planktonic organisms generally occurs when N: P nutrient near or below Redfield 16: 1. In contrast, low estuaries even nutrients inputs low. The tendency toward less plankton coastal marine ecosystems than subject similar loadings may be due a lower availability oxic seawater...
Primary production by seagrasscs in tropical and subtropical carbonate sediments often appears to be phosphorus (P) limited, several studies have sought identify the possible sources of P for long-term growth. Here, we quantify concentrations particulate dissolved fluoride (F−) sediments, sediment-water exchange, leaf-tissue three seagrass beds Bermuda. We also present data on sequential extraction F- from at each site. Total sediment (TPsed) upper 20 cm ranged 650 1,250 mmol m−2 was some...
Based on noninvasive eddy correlation measurements at a marine and freshwater site, this study documents the control that current flow light have sediment‐water oxygen fluxes in permeable sediments. The sediment was exposed to tidal‐driven light, flux varied from night day between −29 78 mmol m −2 d −1 . A fitting model, assuming linear increase respiration with flow, photosynthesis‐irradiance curve for light‐controlled production reproduced measured well ( R 2 = 0.992) revealed 4‐fold...
Abstract Whether net primary productivity in an aquatic ecosystem is limited by nitrogen (N), phosphorus (P), or co-limited N & P determined the relative supply of and to phytoplankton compared their elemental requirements for production, often characterized “Redfield” ratio. The these essential nutrients affected both external inputs biogeochemical processes within ecosystem. In this paper, we examine sources systems how balance influences nutrient limitation. For ocean subtropical...
We measured the uptake rate of molybdate and related kinetic parameters for nine taxa cyanobacteria natural phytoplankton communities six freshwater lakes containing planktonic N 2 ‐fixing cyanobacteria. Molybdate followed saturation kinetics was competitively inhibited by both tungstate sulfate. Tungstate in a nearly mole‐for‐mole fashion; inhibition constants ( K i ) were same concentration range (10–30 nM) as half‐saturation m . Sulfate also uptake, but this much less specific. The...
The success of filamentous nitrogen (N)‐fixing cyanobacteria in productive, transiently N‐limited freshwaters reflects, large part, their ability to produce and sustain the activities specialized N‐fixing heterocyst cells. Heterocyst production is variable, responses planktonic cyanobacterial blooms N limitation differ markedly among systems. Temporal variations colony size may determine both sensitivity top‐down control by zooplankton grazers. We promoted development through phosphorus...
We studied 13 saline lakes in Alberta to test the hypothesis that molybdenum availability influences abundance of planktonic, N‐fixing cyanobacteria ecosystems. Our earlier work oxic seawater showed Mo is controlled part by ratio sulfate because inhibits assimilation molybdate. The SO 4 2− : very high relative most freshwater lakes—a finding consistent with scarcity coastal marine This constant seawater, however, limiting a our systems. These salt provide more robust within any given lake...
Abstract Molybdenum (Mo) is a key cofactor in enzymes used for nitrogen (N) fixation and nitrate reduction, the low availability of Mo can constrain N inputs, affecting ecosystem productivity. Natural atmospheric aerosolization deposition from sources such as desert dust, sea‐salt spray, volcanoes affect function across long timescales, but anthropogenic activities combustion, motor vehicles, agricultural dust have accelerated natural cycle. Here we combined synthesis global concentration...
MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout JournalEditorsTheme Sections 309:25-39 (2006) - doi:10.3354/meps309025 Ecological constraints on planktonic nitrogen fixation in saline estuaries. I. Nutrient and trophic controls Roxanne Marino1,2,*, Francis Chan1,3,4, Robert W. Howarth1,2, Michael L. Pace3, Gene E. Likens3 1Department of & Evolutionary Biology, Cornell University,...