Bulletin, Southern California Academy of Sciences, Aug 1, 2006
Densities of fecal indicator bacteria (FIB) represented by total coliforms, E. coli and enterococ... more Densities of fecal indicator bacteria (FIB) represented by total coliforms, E. coli and enterococci were measured within tidal channels of the Ballona Wetlands (Los Angeles County) to see if the wetlands act as a sink or source for these bacteria and to measure increases in FIB densities during wet weather. Samples were collected on 10 days over a 1-yr period beginning February 2003 at four sites within the wetlands and one site in Ballona Creek opposite the west tide gate. Incoming flood and outgoing ebb tides were sampled during each sampling event at each station. Water from Ballona Creek may be a significant source of indicator bacteria in the wetlands. Within the tidal channels, densities for total coliforms typically ranged from 10 3 -10 4 MPN/100 ml, but ranged up to 10 6 during runoff events. Densities of E. coli and enterococci were orders of magnitude less than those measured for total coliforms, generally ranging from lO'-lO 4 for E. coli, and lO'-lO 5 for enterococci; greater densities were associated with runoff events. Densities of FIB tended to be up to three times greater during flood than ebb tide conditions depending on the tidal range. This result suggests that more
This acknowledgment section is a pleasure to write for two reasons: fi rst, I wi 11 enjoy 1 i sti... more This acknowledgment section is a pleasure to write for two reasons: fi rst, I wi 11 enjoy 1 i sti ng all my fri ends and acquai ntances on both sides of the Pacific Ocean who have helped with this thesis; and second (and perhaps most importantly), it means that I have finished writing the thesis! I will never miss the ever-present question which plagues all graduate students, IIHow' s the wri ti ng comi ng? Are you nearly done?1I Several people have played major roles during various phases of this research, and I would like to give them special thanks. Dr. Jerry Kudenov (fonnerly of the Marine Pollution Studies Group) and my supervisor, Dr. Richard Hudson, arranged for me to study at the University of Melbourne and conduct my field investigation through the Marine Pollution Studies Group (now the Marine Studies Group, Queenscliff). Needless to say, their advice, suggestions, and encouragement were essential, especially during the early stages of my work. When Ri chard 1 eft the department duri ng the fi na 1 stages of my fi el d work, Dr. Graeme Watson took over as my supervisor. Graeme has displayed remarkable dedication in reviewing chapters, answering questions, and all the other details associated with writing a thesis-all by correspondence; I wrote this thesis after I returned home to California. I must point out, however, that Graeme is an avid collector of Australian stamps; it was not unusual to receive an edi ted chapter by special mail, garni shed with stamps and accompanied with a note (usually threatening) to send the stamps back in good condition! iv v A very special acknowledgment goes to my wife, Debby. Wives traditionally are mentioned at the end of these sections, but not here; she has earned a position "up-front. 1I Debby spent many hours helping me collect samples in the field and process them in the laboratory. She successfully weathered many freezi ng southwesterly storms, formal dehyde fumes, bugs, and on one occasion, a dose of alkaline iodine solution on the seat of the pants (from which she bears the scar). On the cerebral side of things, she spent many hours reviewing and proofreading drafts, and gave constant encouragement. With any large research project, many people become involved in all aspects of field, laboratory, and analytical work. I would like to thank Dr. Robert Kelly (formerly of the Mar; ne Poll uti on Stud i es Group) for allowing me to utilize equipment and his excellent staff of technicians during my field work. My fellow graduate students in the Zoology Department gave valuable advice, discussions, occasional field assistance ("You want me to wade into that sewage dra into get worms?! "), 1 anguage lessons, and an invaluable education on Australian beer and wines. These fr; ends i nc1 ude
Environmental Monitoring and Assessment, Jun 3, 2009
California's Clean Beach Initiative (CBI) funds projects to reduce loads of fecal indicator bacte... more California's Clean Beach Initiative (CBI) funds projects to reduce loads of fecal indicator bacteria (FIB) impacting beaches, thus providing an opportunity to judge the effectiveness of various CBI water pollution control strategies. Seventeen initial projects were selected for assessment to determine their effectiveness on reducing FIB in the receiving waters along beaches nearest to the projects. Control strategies included low-flow diversions, sterilization facilities, sewer improvements, pier best management practices (BMPs), vegetative swales, and enclosed beach BMPs. Assessments were based on statistical changes in pre-and postproject mean densities of FIB at shoreline monitoring stations targeted by the projects. Most low-flow diversions and the wetland swale project were effective in removing all contaminated runoff from beaches. UV sterilization was effective when coupled with pretreatment filtration and where effluent was released within a few hundred meters of the beach to avoid FIB regrowth. Other BMPs were less effective because they treated only a portion of contaminant sources impacting their target beach.
Proceedings of a Special Symposium; Coastal Watersheds and their Effects on the Ocean Environment Sponsored by The Southern California Academy of Sciences May 5, 1995
Bulletin, Southern California Academy of Sciences, 1996
A benefit of wetland preservation and restoration is the ecosystem service of improving water qua... more A benefit of wetland preservation and restoration is the ecosystem service of improving water quality, typically assessed based on bacterial loading. The Ballona Wetlands, a degraded salt marsh of approximately 100 ac located on the southern border of Marina Del Rey (Los Angeles County, California, USA) are currently the focus of publicly funded restoration planning. The wetlands receive tidal water, usually contaminated with fecal indicator bacteria (FIB: total and fecal coliforms, Escherichia coli, enterococci) from the adjacent Ballona Creek and Estuary. During the summer of 2007, two 24-h studies were conducted to determine FIB tidal dynamics within the wetland. Measurements of water flow and mean FIB concentrations (n ¼ 3) were measured every 1.5 h to determine total FIB load estimates. FIB loading rates (MPN/s) were greatest during flood tides as water entered the wetlands, and then again during spring tide conditions when sediments were resuspended during swifter spring ebb flows. During daylight hours, the wetland acted as a sink for these bacteria as loads diminished, presumably by sunlight and other processes. Conversely, during late afternoon and night, the wetlands shifted to being a source as excess FIB departed on ebb flows. Therefore, the wetlands act as both a source and sink for FIB depending on tidal conditions and exposure to sunlight. Future restoration actions would result in a tradeoff e increased tidal channels offer a greater surface area for FIB inactivation, but also would result in a greater volume of FIB-contaminated resuspended sediments carried out of the wetlands on stronger ebb flows. As levels of FIB in Ballona Creek and Estuary diminish through recently established regulatory actions, the wetlands could shift into a greater sink for FIB.
Microbiological Monitoring Of Recreational Waters In Santa Monica Bay, California, And The Effects Of Storm Drain Effluents On Three Bacterial Indicators
Microbiological monitoring of recreational waters in Santa Monica Bay, California, and the effect... more Microbiological monitoring of recreational waters in Santa Monica Bay, California, and the effects of storm drain effluents on three bacterial indicators. JA LeMay, MS Bartlett, JH Dorsey 1989. As part of the NPDES monitoring ...
Environmental Monitoring and Assessment, Feb 3, 2015
Stratification and loading of fecal indicator bacteria (FIB) were assessed in the main tidal chan... more Stratification and loading of fecal indicator bacteria (FIB) were assessed in the main tidal channel of the Ballona Wetlands, an urban salt marsh receiving muted tidal flows, to (1) determine FIB concentration versus loading within the water column at differing tidal flows, (2) identify associations of FIB with other water quality parameters, and (3) compare wetland FIB concentrations to the adjacent estuary. Sampling was conducted four times during spring-tide events; samples were analyzed for FIB and turbidity (NTU) four times over a tidal cycle at pre-allocated depths, depending on the water level. Additional water quality parameters measured included temperature, salinity, oxygen, and pH. Loadings were calculated by integrating the stratified FIB concentrations with water column crosssectional volumes corresponding to each depth. Enterococci and Escherichia coli were stratified both by concentration and loading, although these variables portrayed different patterns over a tidal cycle. Greatest concentrations occurred in surface to mid-strata levels, during flood tides when contaminated water flowed in from the estuary, and during ebb flows when sediments were suspended. Loading was greatest during flood flows and diminished during low tide periods. FIB concentrations within the estuary often were significantly greater than those within the wetland tide channel, supporting previous studies that the wetlands act as a sink for FIB. For public health water quality monitoring, these results indicate that more accurate estimates of FIB concentrations would be obtained by sampling a number of points within a water column rather than relying only on single surface samples.
A New Species of Syllides (Polychaeta: Syllidae) with Notes on Amblyosyllis speciosa Izuka from San Clemente Island, California
Bulletin of the Southern California Academy of Sciences, 1978
A new species of Syllides is described and Amblyosyllis speciosa is recorded for the first time f... more A new species of Syllides is described and Amblyosyllis speciosa is recorded for the first time from California. Both species were taken from shallow rocky areas at San Clemente Island
Changes in Assemblages of Infaunal Organisms Around Wastewater Outfalls in Santa Monica Bay, California
Bulletin of the Southern California Academy of Sciences, 1995
The City of Los Angeles\u27 Hyperion Treatment Plant presently operates two submarine outfalls: t... more The City of Los Angeles\u27 Hyperion Treatment Plant presently operates two submarine outfalls: the 1-Mile outfall was used until 1959, but now is used only during emergencies; the plant\u27s main outfall, the 5 -Mile, presently discharges about 1,211 X lO^ld \u27 of mixed primary and secondary effluent at a water depth of 60 m. A third outfall, the now defunct 7-Mile sludge line, operated from 1957- 87, discharging about 15 x 10^ 1 d \u27 of digested sludge into 100 m of water at the head of the Santa Monica Canyon. Solids discharged from Hyperion into the Bay have been greatly reduced since the mid-1980\u27s; sludge disposal was termi- nated, and levels of suspended solids in the 5 -Mile effluent diminished from peak levels of 155 mg/L in 1985 to historically low levels averaging around 30 m.g/L in recent years. Analyses often years of semiannual benthic monitoring data demonstrated that assemblages of benthic organisms near the outfalls have shifted in composition from a polluted condition to one more typical of cleaner reference areas. This trend correlated with reductions of solids discharged from the plant. The infaunal assemblage in the old sludge field has changed from a highly degraded to an early transitional assemblage in terms of species composition and abundance, while those near the 5 -Mile outfall have changed from polluted to a more natural assemblage. Continued recovery is expected, but at a slower rate, if the plant maintains its present effluent quality as it moves towards full secondary treatment in 1998
A New Species of Rhynchospio (Polychaeta: Spionidae) from San Clemente Island, California
Bulletin of the Southern California Academy of Sciences, 1977
A new species of Rhynchospio is described from shallow subtidal rocky areas at San Clemente Islan... more A new species of Rhynchospio is described from shallow subtidal rocky areas at San Clemente Island. Comparisons are made with related Rhynchospio species
This survey was part of a Binational Program (Mexico-United States) in microbiological water qual... more This survey was part of a Binational Program (Mexico-United States) in microbiological water quality, with a goal to assess the shoreline bacteriological water quality from Tijuana to Ensenada, Mexico. Samples were collected at 29 sites (19 beaches and 10 outfalls), from the United States border to Punta Banda, Baja California, during summer (1998) and winter (1999). Total coliforms, fecal coliforms and enterococci were used as bacterial indicators. Standard methods were used for total and fecal coliforms, while the Enterolert quick method (IDEXX) was used for the enterococci. Compared with outfalls, the beaches exceeded water quality standards by a small percent, 25.3% in summer and 17% in winter. For outfalls, the percentage of shoreline that exceeded bacterial indicator thresholds had a minor value in summer (32.7%) than in winter (50%). Sites near wastewater discharges had the lowest quality and did not meet the microbiological water quality criteria for recreational use.
Bulletin of The Biological Society of Washington, 1987
Questions that still surround the origin and early dispersals of maize (Zea mays L.) result in la... more Questions that still surround the origin and early dispersals of maize (Zea mays L.) result in large part from the absence of information on its early history from the Balsas River Valley of tropical southwestern Mexico, where its wild ancestor is native. We report starch grain and phytolith data from the Xihuatoxtla shelter, located in the Central Balsas Valley, that indicate that maize was present by 8,700 calendrical years ago (cal. B.P.). Phytolith data also indicate an early preceramic presence of a domesticated species of squash, possibly Cucurbita argyrosperma. The starch and phytolith data also allow an evaluation of current hypotheses about how early maize was used, and provide evidence as to the tempo and timing of human selection pressure on 2 major domestication genes in Zea and Cucurbita. Our data confirm an early Holocene chronology for maize domestication that has been previously indicated by archaeological and paleoecological phytolith, starch grain, and pollen data from south of Mexico, and reshift the focus back to an origin in the seasonal tropical forest rather than in the semiarid highlands.
Bulletin, Southern California Academy of Sciences, 2010
An overview of the 2009 Station Fire, which burned nearly one-fourth of the Angeles National Fore... more An overview of the 2009 Station Fire, which burned nearly one-fourth of the Angeles National Forest and was the largest fire in the County's history. The arson fire destroyed 102 homes, cabins, and other structures. Two firefighters died when their vehicle went off a cliff. Hidden in these statistics is the toll to native plant and animal species that has occurred and the likely threat of even more damage from debris flow and soil erosion because of winter rains. The sheer size of the Station fire is making recovery and prevention of further damage extremely challenging. It will take many years for the watersheds in the Angeles National Forest to recover. Until then, interagency collaborative efforts and volunteer are essential to protect natural and cultural resources from further damage. Postfire recovery actions are focusing on protecting infrastructure, stabilizing ecosystems, reducing risk of invasive species spread, and restoring 11,000 acres of forested land. The closure of the burned area to the public will help reduce the spread of invasive plant species, protect cultural resources and reduce risk to the public from dangerous conditions created by the destruction of roads, trails and other infrastructure.
California's Clean Beach Initiative (CBI) funds projects to reduce loads of fecal indicator bacte... more California's Clean Beach Initiative (CBI) funds projects to reduce loads of fecal indicator bacteria (FIB) impacting beaches, thus providing an opportunity to judge the effectiveness of various CBI water pollution control strategies. Seventeen initial projects were selected for assessment to determine their effectiveness on reducing FIB in the receiving waters along beaches nearest to the projects. Control strategies included low-flow diversions, sterilization facilities, sewer improvements, pier best management practices (BMPs), vegetative swales, and enclosed beach BMPs. Assessments were based on statistical changes in pre-and postproject mean densities of FIB at shoreline monitoring stations targeted by the projects. Most low-flow diversions and the wetland swale project were effective in removing all contaminated runoff from beaches. UV sterilization was effective when coupled with pretreatment filtration and where effluent was released within a few hundred meters of the beach to avoid FIB regrowth. Other BMPs were less effective because they treated only a portion of contaminant sources impacting their target beach.
Bulletin, Southern California Academy of Sciences, 2009
BioOne sees sustainable scholarly publishing as an inherently collaborative enterprise connecting... more BioOne sees sustainable scholarly publishing as an inherently collaborative enterprise connecting authors, nonprofit publishers, academic institutions, research libraries, and research funders in the common goal of maximizing access to critical research.
Two regional studies conducted during dry weather demonstrated that the Southern California Bight... more Two regional studies conducted during dry weather demonstrated that the Southern California Bight (SCB) shoreline has good water quality, except near areas that drain land-based runoff. Here, we repeat those regional studies 36 h after a rainstorm to assess the influence of runoff under high flow conditions. Two hundred and fifty-four shoreline sites between Santa Barbara, California and Ensenada, Mexico were sampled using a stratified-random sampling design with four strata: sandy beaches, rocky shoreline, shoreline adjacent to urban runoff outlets that flow intermittently, and shoreline adjacent to outlets that flow year-round. Each site was sampled for total coliforms, fecal coliforms (or E. coli), and enterococci. Sixty percent of the shoreline failed water quality standards after the storm compared to only 6% during dry weather. Failure of water quality standards increased to more than 90% for shoreline areas adjacent to urban runoff outlets. During dry weather, most water qual...
Bulletin, Southern California Academy of Sciences, Aug 1, 2006
Densities of fecal indicator bacteria (FIB) represented by total coliforms, E. coli and enterococ... more Densities of fecal indicator bacteria (FIB) represented by total coliforms, E. coli and enterococci were measured within tidal channels of the Ballona Wetlands (Los Angeles County) to see if the wetlands act as a sink or source for these bacteria and to measure increases in FIB densities during wet weather. Samples were collected on 10 days over a 1-yr period beginning February 2003 at four sites within the wetlands and one site in Ballona Creek opposite the west tide gate. Incoming flood and outgoing ebb tides were sampled during each sampling event at each station. Water from Ballona Creek may be a significant source of indicator bacteria in the wetlands. Within the tidal channels, densities for total coliforms typically ranged from 10 3 -10 4 MPN/100 ml, but ranged up to 10 6 during runoff events. Densities of E. coli and enterococci were orders of magnitude less than those measured for total coliforms, generally ranging from lO'-lO 4 for E. coli, and lO'-lO 5 for enterococci; greater densities were associated with runoff events. Densities of FIB tended to be up to three times greater during flood than ebb tide conditions depending on the tidal range. This result suggests that more
This acknowledgment section is a pleasure to write for two reasons: fi rst, I wi 11 enjoy 1 i sti... more This acknowledgment section is a pleasure to write for two reasons: fi rst, I wi 11 enjoy 1 i sti ng all my fri ends and acquai ntances on both sides of the Pacific Ocean who have helped with this thesis; and second (and perhaps most importantly), it means that I have finished writing the thesis! I will never miss the ever-present question which plagues all graduate students, IIHow' s the wri ti ng comi ng? Are you nearly done?1I Several people have played major roles during various phases of this research, and I would like to give them special thanks. Dr. Jerry Kudenov (fonnerly of the Marine Pollution Studies Group) and my supervisor, Dr. Richard Hudson, arranged for me to study at the University of Melbourne and conduct my field investigation through the Marine Pollution Studies Group (now the Marine Studies Group, Queenscliff). Needless to say, their advice, suggestions, and encouragement were essential, especially during the early stages of my work. When Ri chard 1 eft the department duri ng the fi na 1 stages of my fi el d work, Dr. Graeme Watson took over as my supervisor. Graeme has displayed remarkable dedication in reviewing chapters, answering questions, and all the other details associated with writing a thesis-all by correspondence; I wrote this thesis after I returned home to California. I must point out, however, that Graeme is an avid collector of Australian stamps; it was not unusual to receive an edi ted chapter by special mail, garni shed with stamps and accompanied with a note (usually threatening) to send the stamps back in good condition! iv v A very special acknowledgment goes to my wife, Debby. Wives traditionally are mentioned at the end of these sections, but not here; she has earned a position "up-front. 1I Debby spent many hours helping me collect samples in the field and process them in the laboratory. She successfully weathered many freezi ng southwesterly storms, formal dehyde fumes, bugs, and on one occasion, a dose of alkaline iodine solution on the seat of the pants (from which she bears the scar). On the cerebral side of things, she spent many hours reviewing and proofreading drafts, and gave constant encouragement. With any large research project, many people become involved in all aspects of field, laboratory, and analytical work. I would like to thank Dr. Robert Kelly (formerly of the Mar; ne Poll uti on Stud i es Group) for allowing me to utilize equipment and his excellent staff of technicians during my field work. My fellow graduate students in the Zoology Department gave valuable advice, discussions, occasional field assistance ("You want me to wade into that sewage dra into get worms?! "), 1 anguage lessons, and an invaluable education on Australian beer and wines. These fr; ends i nc1 ude
Environmental Monitoring and Assessment, Jun 3, 2009
California's Clean Beach Initiative (CBI) funds projects to reduce loads of fecal indicator bacte... more California's Clean Beach Initiative (CBI) funds projects to reduce loads of fecal indicator bacteria (FIB) impacting beaches, thus providing an opportunity to judge the effectiveness of various CBI water pollution control strategies. Seventeen initial projects were selected for assessment to determine their effectiveness on reducing FIB in the receiving waters along beaches nearest to the projects. Control strategies included low-flow diversions, sterilization facilities, sewer improvements, pier best management practices (BMPs), vegetative swales, and enclosed beach BMPs. Assessments were based on statistical changes in pre-and postproject mean densities of FIB at shoreline monitoring stations targeted by the projects. Most low-flow diversions and the wetland swale project were effective in removing all contaminated runoff from beaches. UV sterilization was effective when coupled with pretreatment filtration and where effluent was released within a few hundred meters of the beach to avoid FIB regrowth. Other BMPs were less effective because they treated only a portion of contaminant sources impacting their target beach.
Proceedings of a Special Symposium; Coastal Watersheds and their Effects on the Ocean Environment Sponsored by The Southern California Academy of Sciences May 5, 1995
Bulletin, Southern California Academy of Sciences, 1996
A benefit of wetland preservation and restoration is the ecosystem service of improving water qua... more A benefit of wetland preservation and restoration is the ecosystem service of improving water quality, typically assessed based on bacterial loading. The Ballona Wetlands, a degraded salt marsh of approximately 100 ac located on the southern border of Marina Del Rey (Los Angeles County, California, USA) are currently the focus of publicly funded restoration planning. The wetlands receive tidal water, usually contaminated with fecal indicator bacteria (FIB: total and fecal coliforms, Escherichia coli, enterococci) from the adjacent Ballona Creek and Estuary. During the summer of 2007, two 24-h studies were conducted to determine FIB tidal dynamics within the wetland. Measurements of water flow and mean FIB concentrations (n ¼ 3) were measured every 1.5 h to determine total FIB load estimates. FIB loading rates (MPN/s) were greatest during flood tides as water entered the wetlands, and then again during spring tide conditions when sediments were resuspended during swifter spring ebb flows. During daylight hours, the wetland acted as a sink for these bacteria as loads diminished, presumably by sunlight and other processes. Conversely, during late afternoon and night, the wetlands shifted to being a source as excess FIB departed on ebb flows. Therefore, the wetlands act as both a source and sink for FIB depending on tidal conditions and exposure to sunlight. Future restoration actions would result in a tradeoff e increased tidal channels offer a greater surface area for FIB inactivation, but also would result in a greater volume of FIB-contaminated resuspended sediments carried out of the wetlands on stronger ebb flows. As levels of FIB in Ballona Creek and Estuary diminish through recently established regulatory actions, the wetlands could shift into a greater sink for FIB.
Microbiological Monitoring Of Recreational Waters In Santa Monica Bay, California, And The Effects Of Storm Drain Effluents On Three Bacterial Indicators
Microbiological monitoring of recreational waters in Santa Monica Bay, California, and the effect... more Microbiological monitoring of recreational waters in Santa Monica Bay, California, and the effects of storm drain effluents on three bacterial indicators. JA LeMay, MS Bartlett, JH Dorsey 1989. As part of the NPDES monitoring ...
Environmental Monitoring and Assessment, Feb 3, 2015
Stratification and loading of fecal indicator bacteria (FIB) were assessed in the main tidal chan... more Stratification and loading of fecal indicator bacteria (FIB) were assessed in the main tidal channel of the Ballona Wetlands, an urban salt marsh receiving muted tidal flows, to (1) determine FIB concentration versus loading within the water column at differing tidal flows, (2) identify associations of FIB with other water quality parameters, and (3) compare wetland FIB concentrations to the adjacent estuary. Sampling was conducted four times during spring-tide events; samples were analyzed for FIB and turbidity (NTU) four times over a tidal cycle at pre-allocated depths, depending on the water level. Additional water quality parameters measured included temperature, salinity, oxygen, and pH. Loadings were calculated by integrating the stratified FIB concentrations with water column crosssectional volumes corresponding to each depth. Enterococci and Escherichia coli were stratified both by concentration and loading, although these variables portrayed different patterns over a tidal cycle. Greatest concentrations occurred in surface to mid-strata levels, during flood tides when contaminated water flowed in from the estuary, and during ebb flows when sediments were suspended. Loading was greatest during flood flows and diminished during low tide periods. FIB concentrations within the estuary often were significantly greater than those within the wetland tide channel, supporting previous studies that the wetlands act as a sink for FIB. For public health water quality monitoring, these results indicate that more accurate estimates of FIB concentrations would be obtained by sampling a number of points within a water column rather than relying only on single surface samples.
A New Species of Syllides (Polychaeta: Syllidae) with Notes on Amblyosyllis speciosa Izuka from San Clemente Island, California
Bulletin of the Southern California Academy of Sciences, 1978
A new species of Syllides is described and Amblyosyllis speciosa is recorded for the first time f... more A new species of Syllides is described and Amblyosyllis speciosa is recorded for the first time from California. Both species were taken from shallow rocky areas at San Clemente Island
Changes in Assemblages of Infaunal Organisms Around Wastewater Outfalls in Santa Monica Bay, California
Bulletin of the Southern California Academy of Sciences, 1995
The City of Los Angeles\u27 Hyperion Treatment Plant presently operates two submarine outfalls: t... more The City of Los Angeles\u27 Hyperion Treatment Plant presently operates two submarine outfalls: the 1-Mile outfall was used until 1959, but now is used only during emergencies; the plant\u27s main outfall, the 5 -Mile, presently discharges about 1,211 X lO^ld \u27 of mixed primary and secondary effluent at a water depth of 60 m. A third outfall, the now defunct 7-Mile sludge line, operated from 1957- 87, discharging about 15 x 10^ 1 d \u27 of digested sludge into 100 m of water at the head of the Santa Monica Canyon. Solids discharged from Hyperion into the Bay have been greatly reduced since the mid-1980\u27s; sludge disposal was termi- nated, and levels of suspended solids in the 5 -Mile effluent diminished from peak levels of 155 mg/L in 1985 to historically low levels averaging around 30 m.g/L in recent years. Analyses often years of semiannual benthic monitoring data demonstrated that assemblages of benthic organisms near the outfalls have shifted in composition from a polluted condition to one more typical of cleaner reference areas. This trend correlated with reductions of solids discharged from the plant. The infaunal assemblage in the old sludge field has changed from a highly degraded to an early transitional assemblage in terms of species composition and abundance, while those near the 5 -Mile outfall have changed from polluted to a more natural assemblage. Continued recovery is expected, but at a slower rate, if the plant maintains its present effluent quality as it moves towards full secondary treatment in 1998
A New Species of Rhynchospio (Polychaeta: Spionidae) from San Clemente Island, California
Bulletin of the Southern California Academy of Sciences, 1977
A new species of Rhynchospio is described from shallow subtidal rocky areas at San Clemente Islan... more A new species of Rhynchospio is described from shallow subtidal rocky areas at San Clemente Island. Comparisons are made with related Rhynchospio species
This survey was part of a Binational Program (Mexico-United States) in microbiological water qual... more This survey was part of a Binational Program (Mexico-United States) in microbiological water quality, with a goal to assess the shoreline bacteriological water quality from Tijuana to Ensenada, Mexico. Samples were collected at 29 sites (19 beaches and 10 outfalls), from the United States border to Punta Banda, Baja California, during summer (1998) and winter (1999). Total coliforms, fecal coliforms and enterococci were used as bacterial indicators. Standard methods were used for total and fecal coliforms, while the Enterolert quick method (IDEXX) was used for the enterococci. Compared with outfalls, the beaches exceeded water quality standards by a small percent, 25.3% in summer and 17% in winter. For outfalls, the percentage of shoreline that exceeded bacterial indicator thresholds had a minor value in summer (32.7%) than in winter (50%). Sites near wastewater discharges had the lowest quality and did not meet the microbiological water quality criteria for recreational use.
Bulletin of The Biological Society of Washington, 1987
Questions that still surround the origin and early dispersals of maize (Zea mays L.) result in la... more Questions that still surround the origin and early dispersals of maize (Zea mays L.) result in large part from the absence of information on its early history from the Balsas River Valley of tropical southwestern Mexico, where its wild ancestor is native. We report starch grain and phytolith data from the Xihuatoxtla shelter, located in the Central Balsas Valley, that indicate that maize was present by 8,700 calendrical years ago (cal. B.P.). Phytolith data also indicate an early preceramic presence of a domesticated species of squash, possibly Cucurbita argyrosperma. The starch and phytolith data also allow an evaluation of current hypotheses about how early maize was used, and provide evidence as to the tempo and timing of human selection pressure on 2 major domestication genes in Zea and Cucurbita. Our data confirm an early Holocene chronology for maize domestication that has been previously indicated by archaeological and paleoecological phytolith, starch grain, and pollen data from south of Mexico, and reshift the focus back to an origin in the seasonal tropical forest rather than in the semiarid highlands.
Bulletin, Southern California Academy of Sciences, 2010
An overview of the 2009 Station Fire, which burned nearly one-fourth of the Angeles National Fore... more An overview of the 2009 Station Fire, which burned nearly one-fourth of the Angeles National Forest and was the largest fire in the County's history. The arson fire destroyed 102 homes, cabins, and other structures. Two firefighters died when their vehicle went off a cliff. Hidden in these statistics is the toll to native plant and animal species that has occurred and the likely threat of even more damage from debris flow and soil erosion because of winter rains. The sheer size of the Station fire is making recovery and prevention of further damage extremely challenging. It will take many years for the watersheds in the Angeles National Forest to recover. Until then, interagency collaborative efforts and volunteer are essential to protect natural and cultural resources from further damage. Postfire recovery actions are focusing on protecting infrastructure, stabilizing ecosystems, reducing risk of invasive species spread, and restoring 11,000 acres of forested land. The closure of the burned area to the public will help reduce the spread of invasive plant species, protect cultural resources and reduce risk to the public from dangerous conditions created by the destruction of roads, trails and other infrastructure.
California's Clean Beach Initiative (CBI) funds projects to reduce loads of fecal indicator bacte... more California's Clean Beach Initiative (CBI) funds projects to reduce loads of fecal indicator bacteria (FIB) impacting beaches, thus providing an opportunity to judge the effectiveness of various CBI water pollution control strategies. Seventeen initial projects were selected for assessment to determine their effectiveness on reducing FIB in the receiving waters along beaches nearest to the projects. Control strategies included low-flow diversions, sterilization facilities, sewer improvements, pier best management practices (BMPs), vegetative swales, and enclosed beach BMPs. Assessments were based on statistical changes in pre-and postproject mean densities of FIB at shoreline monitoring stations targeted by the projects. Most low-flow diversions and the wetland swale project were effective in removing all contaminated runoff from beaches. UV sterilization was effective when coupled with pretreatment filtration and where effluent was released within a few hundred meters of the beach to avoid FIB regrowth. Other BMPs were less effective because they treated only a portion of contaminant sources impacting their target beach.
Bulletin, Southern California Academy of Sciences, 2009
BioOne sees sustainable scholarly publishing as an inherently collaborative enterprise connecting... more BioOne sees sustainable scholarly publishing as an inherently collaborative enterprise connecting authors, nonprofit publishers, academic institutions, research libraries, and research funders in the common goal of maximizing access to critical research.
Two regional studies conducted during dry weather demonstrated that the Southern California Bight... more Two regional studies conducted during dry weather demonstrated that the Southern California Bight (SCB) shoreline has good water quality, except near areas that drain land-based runoff. Here, we repeat those regional studies 36 h after a rainstorm to assess the influence of runoff under high flow conditions. Two hundred and fifty-four shoreline sites between Santa Barbara, California and Ensenada, Mexico were sampled using a stratified-random sampling design with four strata: sandy beaches, rocky shoreline, shoreline adjacent to urban runoff outlets that flow intermittently, and shoreline adjacent to outlets that flow year-round. Each site was sampled for total coliforms, fecal coliforms (or E. coli), and enterococci. Sixty percent of the shoreline failed water quality standards after the storm compared to only 6% during dry weather. Failure of water quality standards increased to more than 90% for shoreline areas adjacent to urban runoff outlets. During dry weather, most water qual...
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