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Full-Text Articles in Physical Sciences and Mathematics

Ecological Response Of Phytoplankton To The Oil Spills In The Oceans, Danling Tang, Jing Sun, Li Zhou, Sufen Wang, Ramesh P. Singh, Gang Pan Feb 2019

Ecological Response Of Phytoplankton To The Oil Spills In The Oceans, Danling Tang, Jing Sun, Li Zhou, Sufen Wang, Ramesh P. Singh, Gang Pan

Mathematics, Physics, and Computer Science Faculty Articles and Research

Oil spills in oceans have substantial influence on marine ecosystems. This study investigates 21 oil spills in the world. Analyzing Chlorophyll-a (Chl-a) from Moderate Resolution Imaging Spectroradiomerer (MODIS) data after Penglai oil spills on 4 June 2011, found a bloom with peak value of Chl-a (13.66 mg m−3) spread over an area of 800 km2 during 18–25 June 2011, and a pronounced increase in the monthly Chl-a concentration (6.40 mg m−3) on June 2012 in the Bohai Sea. Out of the 21 oil spills, 14 blooms were observed, while 11 …


Associated Dataset: Climate Change Impacts On Southern Ross Sea Phytoplankton Composition, Productivity And Export, Daniel E. Kaufman, Marjorie A.M. Friedrichs, Walker O. Smith Jr., Eileen E. Hofmann, Michael S. Dinniman, John C.P. Hemmings Jan 2017

Associated Dataset: Climate Change Impacts On Southern Ross Sea Phytoplankton Composition, Productivity And Export, Daniel E. Kaufman, Marjorie A.M. Friedrichs, Walker O. Smith Jr., Eileen E. Hofmann, Michael S. Dinniman, John C.P. Hemmings

Data

This dataset includes data used in the publication Kaufman et al., 2017, JGR-Oceans, which investigates how these climatic changes in the Ross Sea, Antarctica, may alter phytoplankton composition, primary productivity and export. A one-dimensional version of the Model of Ecosystem Dynamics, nutrient Utilisation, Sequestration and Acidification was adapted for use in the Ross Sea (MEDUSA-RS). Glider measurements were used to force MEDUSA-RS, which includes diatoms and both solitary and colonial forms of Phaeocystis antarctica. Model performance was evaluated with glider observations, and experiments were conducted using projections of physical drivers for mid- and late-21st century. Additional scenarios examined the …


Sea Surface Temperature Rises Shift Migration Patterns Due To Ecosystem Changes, Alexia Skrbic, Hesham El-Askary Dec 2016

Sea Surface Temperature Rises Shift Migration Patterns Due To Ecosystem Changes, Alexia Skrbic, Hesham El-Askary

Student Scholar Symposium Abstracts and Posters

The continuing climate change is negatively impacting ecosystems, specifically oceans which are declining and food webs are being altered by the increase of greenhouse gases. The increase of the carbon dioxide and other greenhouse gases is increasing sea surface temperature of the world’s oceans. Certain organisms lower on the food chain like phytoplankton and zooplankton are directly affected by the warming which alters how they process nutrients and their productivity. The limited amount of these primary producers in the oceans and specifically the location they inhabit directly affects all the organisms above them on the food chain. Several marine animals …


How The Presence Of Plastic In The North Pacific Gyre Affects The Growth Of Thalassiosira Through Remote Sensing And Laboratory Replication, Jordynn Brennan, Hesham El-Askary Dec 2014

How The Presence Of Plastic In The North Pacific Gyre Affects The Growth Of Thalassiosira Through Remote Sensing And Laboratory Replication, Jordynn Brennan, Hesham El-Askary

Student Scholar Symposium Abstracts and Posters

Through the use of remote sensing, we are able to determine the approximate location of the garbage patch in the North Pacific Gyre. Though remote sensing does not penetrate the surface of the ocean, monthly satellite images can be analyzed to determine the rate of growth or rate of decrease of certain parameters, such as atmospheric gases, phytoplankton, and dissolved organic matter. Over the past decade, data from the Goddard Earth Sciences Data and Information Services Center (Giovanni program) has shown a significant increase in dissolved organic matter and chlorophyll a content in the area of the North Pacific Garbage …


Combating Eutrophication: An Ecosystem Scale Analysis Of Aluminum Sulfate (Alum) Effectiveness Among Lakes, With Comparison To Alum And Biomanipulation Dual Treatment, Christa M. Webber Dec 2014

Combating Eutrophication: An Ecosystem Scale Analysis Of Aluminum Sulfate (Alum) Effectiveness Among Lakes, With Comparison To Alum And Biomanipulation Dual Treatment, Christa M. Webber

School of Natural Resources: Dissertations, Theses, and Student Research

Eutrophic conditions in lakes and reservoirs in agricultural regions often drive summer blooms of toxic cyanobacteria. Aluminum sulfate (alum) applications are commonly used to control cyanobacteria blooms and restore water quality in eutrophic lakes. However, studies of alum treatments often lack true replication, comparison to reference lakes, or comparison to other restoration techniques, such as an alum and biomanipulation combined or “dual” treatments. Without these comparisons, the variation of treatment response between replicate lakes and restoration techniques remains uncertain. Therefore, I sought to assess how water quality is affected by multiple restoration techniques among geographically proximate (1.4 km2) …


Interactions Of Zooplankton And Phytoplankton With Cyanobacteria, Rebecca Alexander Dec 2012

Interactions Of Zooplankton And Phytoplankton With Cyanobacteria, Rebecca Alexander

School of Natural Resources: Dissertations, Theses, and Student Research

Cyanobacteria are a major concern in Nebraska reservoirs and are capable of producing toxins that can cause skin irritations and gastrointestinal problems, as well as affect the nervous system. It is important to determine the mechanisms that can cause cyanobacteria blooms due to the effect they can have on human health. The interaction of zooplankton and other phytoplankton groups with cyanobacteria is important because there is a biological component in surface waters that should be taken into consideration along with the physical and chemical parameters that have been noted to promote cyanobacteria. For example, zooplankton have the ability to alter …


Study Of Existing Information Concerning Water Quality Within Lake Mead, Vicki Scharnhorst, Southern Nevada Water Authority Feb 1994

Study Of Existing Information Concerning Water Quality Within Lake Mead, Vicki Scharnhorst, Southern Nevada Water Authority

Publications (WR)

The purpose of Task 010A15M of the Southern Nevada Water Authority (SNWA) Treatment and Transmission Facility (TTF) contract is to conduct a study of existing information concerning water quality within Lake Mead and identify additional water quality studies that are needed to supplement existing data.

The objective of this task is not to discuss treatability of the raw water source; this is addressed by Task 010A18M, "Define Water Treatment Requirements." In addition, a narrative on the effect of pending Safe Drinking Water Act amendments and a determination of treated water quality goals is included in Task 010A16M, "Review Safe Drinking …


Draft- Nitrogen Loading And Ambient Chlorophyll-A In Hillsborough Bay (Tampa Bay), Florida: An Eutrophication Management Strategy, J.O. R. Johansson Feb 1990

Draft- Nitrogen Loading And Ambient Chlorophyll-A In Hillsborough Bay (Tampa Bay), Florida: An Eutrophication Management Strategy, J.O. R. Johansson

Reports

The present report examines the past and current relationship between nitrogen loadings and ambient chlorophyll-a eutrophic subdivision of Tampa Bay (Task 1). A management strategy for eutrophication abatement, involving the reduction of present nitrogen loadings to levels which will sustain the desirable chlorophyll-a concentration and support persistent seagrass growth in the near future, is also presented for Hillsborough Bay (Task 3). The urgent need for a comprehensive long-term water quality and loading source monitoring program, specifically for Hillsborough Bay, is also discussed (Task 4).


Recent Improvements Of Water Quality And Biological Indicators In Hillsborough Bay, The Northeastern Section Of Tampa Bay, Florida, J.O. R. Johansson Apr 1989

Recent Improvements Of Water Quality And Biological Indicators In Hillsborough Bay, The Northeastern Section Of Tampa Bay, Florida, J.O. R. Johansson

Reports

The City of Tampa was implicated as a major point source polluter of Hillsborough Bay based on its release since 1951 of primary treated wastewater effluent into the bay. To alleviate nutrient loads into Hillsborough Bay, the City of Tampa upgraded its Hooker's Point facility to advanced wastewater treatment (AWT) with a 60 MGD capacity. The transformation from primary treatment to advanced was successive.


Surface Sediments And Their Relationship To Water Quality In Hillsborough Bay, A Highly Impacted Subdivision Of Tampa Bay, Florida, J.O.R. Johansson, A.P. Squires Jan 1989

Surface Sediments And Their Relationship To Water Quality In Hillsborough Bay, A Highly Impacted Subdivision Of Tampa Bay, Florida, J.O.R. Johansson, A.P. Squires

Reports

This paper will summarize the composition of surface sediment and sediment oxygen demand rated in Hillsborough Bay. Also, a first attempt is made to relate the nutrients released from these sediments to the phytoplankton, the dominant primary producers of the bay.


An Ongoing Survey Of Halodule Wrightii, Ruppia Maritima And The Alga, Caulerpa Prolifera, In Hillsborough Bay, Florida, City Of Tampa Department Of Sanitary Sewers Jun 1988

An Ongoing Survey Of Halodule Wrightii, Ruppia Maritima And The Alga, Caulerpa Prolifera, In Hillsborough Bay, Florida, City Of Tampa Department Of Sanitary Sewers

Reports

The Bay Study Group intends to periodically monitor seagrass coverage, seagrass speciecs composition, and C. prolifera coverage within Hillsborough Bay and adjacent waters. Potential relationships between various environmental parameters and seagrass coverage will be investigated. Results should provide valuable information concerning natural seagrass renewal and rates of seagrass growth. Such information is much needed in order to make sound decisions concerning seagrass restoration and viable mitigation options.


Estimation Of Food Limitation In Daphnia Pulex From Boulder Basin, Lake Mead, Thomas Mark Bartanen Aug 1987

Estimation Of Food Limitation In Daphnia Pulex From Boulder Basin, Lake Mead, Thomas Mark Bartanen

Publications (WR)

In February, 1982 I began a year-long study to determine if growth and reproduction in Daphnia Pulex were limited by the amount of food available in Boulder Basin, Lake Mead. To determine this, I made monthly collections of Daphnia Pulex and natural lake seston from an already established station in Boulder Basin. I cultured the Daphnia Pulex under simulated field conditions in a flow-through feeding apparatus using four different food regimes; 1-natural lake seston filtered through 80 um mesh to remove other zooplankton, 2-lake seston (as above) with an enrichment of 103 cells-ml-1 of Chlamydomonas reinhardti, 3-lake …


Recent Improvements Of Water Quality And Biological Indicators In The North-Eastern Tampa Bay, City Of Tampa Bay Department Of Sanitary Sewers May 1987

Recent Improvements Of Water Quality And Biological Indicators In The North-Eastern Tampa Bay, City Of Tampa Bay Department Of Sanitary Sewers

Reports

Simple analysis of our data clearly indicate that water quality conditions in north-eastern Tampa Bay has improved during our study. Further, there are no indications that this improvement has yet climaxed.


A Proposal To Fertilize The Overton Arm And Gregg Basin Areas Of Lake Mead, Larry J. Paulson Nov 1984

A Proposal To Fertilize The Overton Arm And Gregg Basin Areas Of Lake Mead, Larry J. Paulson

Publications (WR)

Several limnological studies have been conducted in Lake Mead during the past decade. The recent studies clearly show that most of Lake Mead is deficient in nutrients, especially phosphorus, and very low in productivity. The reservoir-wide average total phosphorus concentration for 1981 - 1982 was only 9 mg/m3. This is below levels found In most oligotrophic lakes and reservoirs. Algal biomass, as measured by chlorophyll-a, averaged only 1.5 mg/m3. That also places Lake Mead in the oligotrophic range. Transparency, as measured by a Secchi disc, averaged 9-5 m in Lake Mead during 1981-1982. That far exceeds …


Seasonal And Spatial Heterogeneity In The Limnetic Zooplankton Community Of Lake Mead, Gene Robert Wilde May 1984

Seasonal And Spatial Heterogeneity In The Limnetic Zooplankton Community Of Lake Mead, Gene Robert Wilde

Publications (WR)

Zooplankton samples collected from throughout Lake Mead, in 1981-1982, demonstrate the presence of a statistically significant seasonal and spatial heterogeneity in zooplankton densities. Seasonally, the major zooplankton groups were most abundant in the spring and fall, coincident with maxima in chlorophyll-a concentrations. Successions among the various rotifers, cladocerans and copepods present in the reservoir were influenced by food availability, diapause, predation by planktivorous fish and, possibly, water temperatures.

Spatial heterogeneity in zooplankton densities was unrelated to water temperature, pH, conductivity and dissolved oxygen concentrations, but was related to the abundance of phytoplankton (chlorophyll-a concentrations) and fish. Statistical analyses indicate that …


The Role Of Nannoplankton In The Phytoplankton Dynamics Of Four Colorado River Reservoirs (Lakes Powell, Mead, Mohave, And Havasu), Jeffrey John Janik May 1984

The Role Of Nannoplankton In The Phytoplankton Dynamics Of Four Colorado River Reservoirs (Lakes Powell, Mead, Mohave, And Havasu), Jeffrey John Janik

Publications (WR)

Phytoplankton species composition and community size structure were studied in four warm-monomictic Colorado River reservoirs; lakes Powell, Mead, Mohave, and Havasu from March 1981 to February 1982. Sampling was done at approximately monthly intervals from several stations in each reservoir. The Utermohl technique was used to enumerate phytoplankton. The phytoplankton assemblage was divided into the following six size classes using microscopic techniques; netplankton (>64 um), and nannoplankton (>5, 5-11, 12-21, 22-44, and 45-64 um).

Total phytoplankton biomass and community size structure were different among these four reservoirs with considerable spatial and temporal variation present. Average reservoir-wide areal weighted …


The Effects Of Limited Food Availability On The Striped Bass Fishery In Lake Mead, John R. Baker, Larry J. Paulson Jan 1983

The Effects Of Limited Food Availability On The Striped Bass Fishery In Lake Mead, John R. Baker, Larry J. Paulson

Publications (WR)

The original range of striped bass (Morone saxatilis) was along the Atlantic Coast. They were introduced into the lower Sacramento River in 1879 and are now also found along the Pacific Coast. A landlocked striped bass fishery was established in Santee-Cooper Reservoir, South Carolina, in 1954, and they have since been introduced into numerous other reservoirs, including Lake Havasu, Lake Mead and Lake Powell on the Colorado River. Striped bass were introduced into Lake Mead in 1969 in response to declines in the largemouth bass (Micropterus salmoides) fishery that occurred during the 1960s and in order to further utilize the …


Historical Patterns Of Phytoplankton Productivity In Lake Mead, Richard T. Prentki, Larry J. Paulson Jan 1983

Historical Patterns Of Phytoplankton Productivity In Lake Mead, Richard T. Prentki, Larry J. Paulson

Publications (WR)

Lake Mead was impounded in 1935 by the construction of Hoover Dam. The Colorado River was unregulated prior to then and therefore was subjected to extreme variations in flows and suspended sediment loads. Hoover Dam stabilized flows and reduced suspended sediment loads downstream, but Lake Mead still received silt-laden inflows from the upper Colorado River Basin. The Colorado River contributed 97% of the suspended sediment inputs to Lake Mead, and up to 140 x 1O6 metric tons (t) entered the reservoir in years of high runoff. Most of the sediments were deposited in the river channel and formed an …


Effects Of Wastewater Discharges On Periphyton Growth In Lake Mead, Nevada-Arizona, Marsha Korb Morris Dec 1982

Effects Of Wastewater Discharges On Periphyton Growth In Lake Mead, Nevada-Arizona, Marsha Korb Morris

Publications (WR)

A study of the effects of secondary-treated wastewater on periphyton growth in Lake Mead, Nevada-Arizona was conducted from September 1979 to December 1980. Periphyton ash-free dry weight, chlorophyll-a, dominant species composition, and alkaline phosphatase activity were measured on fiberglass substrates. Substrates were incubated for two to four weeks in littoral and limnetic habitats. Physical and chemical variables and phytoplankton chlorophyll-a were measured concurrently.

Transparency increased with increasing distance from the discharge. Secchi depth ranged from 0.75 m at the discharge confluence (station 2) in August, to greater than 20 m at the most distant stations (stations 9 and 10) in …


Final Report Of The Hillsborough Bay Water Quality Monitoring Program, City Of Tampa Department Of Sanitary Sewers Mar 1981

Final Report Of The Hillsborough Bay Water Quality Monitoring Program, City Of Tampa Department Of Sanitary Sewers

Reports

The report presented here is the final communication of data collected during the first year and a half of plant operation at variance standards. In addition, earlier data collected by the City of Tampa are also presented in this report in order to give background information of conditions existing prior to operation under the variance (Appendix C). The earlier data may also describe long term trends and normal seasonal cycles occurring in the bay.


Methods For Biological, Chemical, And Physical Analyses In Reservoirs, Penelope E. Kellar, Sherell A. Paulson, Larry J. Paulson Dec 1980

Methods For Biological, Chemical, And Physical Analyses In Reservoirs, Penelope E. Kellar, Sherell A. Paulson, Larry J. Paulson

Publications (WR)

This manual contains detailed descriptions of biological, chemical and physical sampling and analytical procedures used at the Lake Mead Limnological Research Center. The manual was prepared in response to requests made by numerous individuals involved in the Las Vegas Valley Water Quality Program. This manual represents what we consider to be a reasonably complete compilation of methods useful in studying both general and specific limnological questions. While each section is sufficiently detailed to be of use to investigators with little experience in limnological methodology, the methods can be used on a wide variety of lakes and reservoirs, with relatively little …


Influence Of Las Vegas Wash Density Current On Nutrient Availability And Phytoplankton Growth In Lake Mead, John R. Baker, Larry J. Paulson Jun 1980

Influence Of Las Vegas Wash Density Current On Nutrient Availability And Phytoplankton Growth In Lake Mead, John R. Baker, Larry J. Paulson

Publications (WR)

Density currents are commonly formed in reservoirs because of temperature or salinity induced density differences between inflowing and receiving waters. Anderson and Pritchard (1951) were among the first to demonstrate this in their investigations of density currents in Lake Mead. They found that the Colorado River formed an underflow in Lake Mead during the winter, an overflow in the spring and an interflow in the summer and fall. Wunderlich and Elder (1973) have since described the hydromechanics of these types of flow patterns, and density currents have been reported for several other large reservoirs (Carmack et al. 1979, Johnson and …


Evaluation Of Impacts Associated With Reregulation Of Water Levels In Lake Mohave, Larry J. Paulson, John R. Baker, U.S. Water And Power Resources Service Mar 1980

Evaluation Of Impacts Associated With Reregulation Of Water Levels In Lake Mohave, Larry J. Paulson, John R. Baker, U.S. Water And Power Resources Service

Publications (WR)

The U.S. Water and Power Resources Service is considering reregulating Lake Mohave water levels to increase the net power benefit from Hoover Dam. Reregulation will not increase the generation capacity of the Hoover powerplant but it will enable the plant operation to be increased when the energy has greater monetary value. Energy generated at different times of the year has different market value, the highest being in January-March and July- September. By generating more power during these periods more net monetary benefit can be derived from Hoover Dam. The total volume of water released from Hoover Dam over an annual …


Influence Of Dredging And High Discharge On The Ecology Of Black Canyon, Larry J. Paulson, Theron G. Miller, John R. Baker, U.S. Water And Power Resources Service Jan 1980

Influence Of Dredging And High Discharge On The Ecology Of Black Canyon, Larry J. Paulson, Theron G. Miller, John R. Baker, U.S. Water And Power Resources Service

Publications (WR)

The Water and Power Resources Service is considering dredging in Black Canyon to create a larger forebay to accommodate higher peak discharges and reverse flows for proposed modifications to Hoover Dam.

The Black Canyon area from Hoover Dam to Willow Beach supports a heavily utilized trout fishery and is important habitat for the razorback sucker (Xyrauchen texanus) and possibly bonytail chub (Gila elegans).

The Water and Power Resources Service initiated this investigation to determine what effect dredging and higher peak-discharges would have on the ecology of Black Canyon.


The Limnological Status Of Lake Mead And Lake Mohave Under Present And Future Powerplant Operations Of Hoover Dam, Larry J. Paulson, John R. Baker, James E. Deacon, U.S. Water And Power Resources Service Jan 1980

The Limnological Status Of Lake Mead And Lake Mohave Under Present And Future Powerplant Operations Of Hoover Dam, Larry J. Paulson, John R. Baker, James E. Deacon, U.S. Water And Power Resources Service

Publications (WR)

The ever-increasing demand for energy in the southwest has led to a search for additional sources of power generation. Coal-fired powerplants currently provide most of the baseline energy in the southwest, but this must be supplemented with hydroelectric power during periods of peak demand. In order to provide additional peaking power, the U.S. Bureau of Reclamation is considering a number of projects to modify existing hydroelectric facilities, or add new facilities in the Lake Mead Recreation Area.

The Hoover Powerplant Modification Feasibility Investigation was authorized by Congress on December 16, 1975 to determine the feasibility of: (i) adding one or …


Potential Use Of Hydroelectric Facilities For Manipulating The Fertility Of Lake Mead, Larry J. Paulson, John R. Baker, James E. Deacon Jan 1979

Potential Use Of Hydroelectric Facilities For Manipulating The Fertility Of Lake Mead, Larry J. Paulson, John R. Baker, James E. Deacon

Publications (WR)

Analysis of historical nutrient data for Lake Mead indicates that the fertility of the reservoir has decreased which may be the cause for a corresponding decline in the largemouth bass population. However, it appears that fertility can be manipulated by altering the operation of the dam. The depletion of nutrients in the euphotic zone by phytoplankton and subsequent accumulation in the hypolimnion during summer and fall provide a natural nutrient gradient from which water of varying fertility can be drawn for discharge. This combined with alterations in the depth or seasonal pattern of discharge can possibly be used to enhance …


Limnological Aspects Of Lake Mead, Nevada-Arizona, John R. Baker, James E. Deacon, Thomas A. Burke, Samuel S. Egdorf, Larry J. Paulson, Richard W. Tew, Bureau Of Reclamation Jun 1977

Limnological Aspects Of Lake Mead, Nevada-Arizona, John R. Baker, James E. Deacon, Thomas A. Burke, Samuel S. Egdorf, Larry J. Paulson, Richard W. Tew, Bureau Of Reclamation

Publications (WR)

Lake Mead is a deep, subtropical, moderately productive, desert impoundment with a negative heterograde oxygen profile occurring during; the summer stratification. investigations of the Boulder Basin of Lake Mead by the University of Nevada were initiated in November 1971. The primary objective of the study was to determine what effects industrial and sewage effluent from the Las Vegas metropolitan area, discharged into Las Vegas Bay, have had on the water quality and limnological conditions of Boulder Basin. Data from the 1975-76 period are presented in detail, with earlier data included in the summaries and discussions.

Measurements of water temperature, dissolved …


Ancolote Power Station Post-Operational Plankton Monitoring Program: Vol 1 Technical Discussion, Westinghouse Electric Corporation, Environmental Systems Department (Pa) Jun 1977

Ancolote Power Station Post-Operational Plankton Monitoring Program: Vol 1 Technical Discussion, Westinghouse Electric Corporation, Environmental Systems Department (Pa)

Reports

The affect of the Anclote Power Station on the plankton community was evaluated by (1) determining differences among stations, (2) comparing results from the post-operational plankton monitoring program, 93) examining any major changes in seasonal cycles from those expected of plankton communities in shallow-water, subtropical estuaries and (4) determining the frequency of occurrence and extent of temperatures known to adversely affect the copepods Acartia tonsa and Oithona spp.


Anclote Power Station Post-Operational Plankton Monitoring Program: Vol 2 Appendices, Florida Power Corporation Apr 1977

Anclote Power Station Post-Operational Plankton Monitoring Program: Vol 2 Appendices, Florida Power Corporation

Reports

Appendix IV-A through appendix IV-F


A Review Of The Limnology Of And Water Quality Standards For Lake Mead, Charles R. Goldman Oct 1976

A Review Of The Limnology Of And Water Quality Standards For Lake Mead, Charles R. Goldman

Publications (WR)

1. The waters of Las Vegas Bay, a heavily utilized recreational resource, receive discharges from a variety of municipal and industrial waste sources. The U.S. Environmental Protection Agency has determined, on the basis of numerous studies, that the present water quality violates state and federal standards and constitutes a public nuisance. Consultants have advised the Sewage and Wastewater Advisory Committee that rapid abatement of the alleged pollution conditions can be achieved by an advanced wastewater treatment (AWT) plant.

2. The major problems in Las Vegas Bay are an objectionable water color, excessive turbidity, noxious odors, and oxygen depletion in certain …