Comprehensive demographic dataset for Northridge, Los Angeles, CA, US including population statistics, household income, housing units, education levels, employment data, and transportation with year-over-year changes.

Demographics, population, housing, income, education, schools, and geography for ZIP Code 91324 (Northridge, CA). Interactive charts load automatically as you scroll for improved performance.

Comprehensive demographic dataset for Northridge Greens, Fair Oaks, CA, US including population statistics, household income, housing units, education levels, employment data, and transportation with year-over-year changes.

Comprehensive demographic dataset for Northridge Woods, Citrus Heights, CA, US including population statistics, household income, housing units, education levels, employment data, and transportation with year-over-year changes.

The influence of density-dependent and number-dependent processes on individual demographic rates often results in ecological tradeoffs. Because such processes have important implications for individual level fitness and population regulation, they long have been an important topic in ecological research. I used Dascyllus trimaculatus , a site-attached planktivorous coral reef fish, to determine independently the effects of population density and group size on rates of individual growth and mortality. Somatic growth of D. trimaculatus was positively related to the density of D. trimaculatus outplanted to host anenomes, Heteractis magnifica , with nearly twice as much growth observed in individuals living in the highest density treatment. By contrast, survivorship of D. trimaculatus on H. magnifica exhibited a negative relationship with density. There was no significant effect of group size on either the growth or mortality rates of D. trimaculatus . These relationships suggest a tradeoff between density-dependent growth and survival in this species. My analysis of behavioral data indicated that D. trimaculatus living under conditions of higher local population densities displayed decreased rates of intraspecific aggression because of positive feedback between local population density and the foraging distance from an individual’s host anemone. In turn, lower rates of aggression and feeding higher in the water column resulted in increased somatic growth rates due to: (1) a reduced energy expenditure and (2) an increase in prey consumption. These data are part of a Master's Thesis published by ProQuest: Nielsen, Jessica Anne. Effects of density on behaviorally-mediated tradeoffs between growth and survivorship. MA Thesis, University of California Santa Barbara, 2013. This material is based upon work supported by the U.S. National Science Foundation under Grant No. OCE 16-37396 (and earlier awards) as well as a generous gift from the Gordon and Betty Moore Foundation. Research was completed under permits issued by the French Polynesian Government (Délégation à la Recherche) and the Haut-commissariat de la République en Polynésie Francaise (DTRT) (Protocole d'Accueil 2005-2018). This work represents a contribution of the Moorea Coral Reef (MCR) LTER Site.

Comprehensive demographic dataset for Northridge Knolls, Citrus Heights, CA, US including population statistics, household income, housing units, education levels, employment data, and transportation with year-over-year changes.

In this study, size-based matrix models for the reef-building coral Orbicella annularis at 14-m depth on the Tektite reef in St. John, U.S. Virgin Islands, were used to: (1) explore the demography of changing coral cover over 25 yr, (2) test for spatial homogeneity in demographic properties through a contrast with a previous study (at Yawzi Point, Edmunds and Elahi 2007), and (3) evaluate the potential for future population stability. During three, five year intervals from 1988 to 2002, St. John was affected by hurricanes and bleaching, yet coral cover at Tektite increased from 33% to 49%; from 2002 to 2007, it declined to 27%; and from 2010 to 2013, it stabilized at ∼ 28%. Over a quarter-century, colonies > 50 cm2 became rare, the abundance of colonies ≤ 50 cm2 increased from 58% (1988) to 92% (2013), and population density doubled to 67 colonies m-2 by 2013. Population growth (λ) was greater at Tektite (1.152 ≥ λ ≥ 1.018) than Yawzi Point (0.679 ≥ λ ≥ 0.586), and while population size at Tektite declined due to bleaching and disease in 2005 (λ = 0.753 over 2003–2008), it recovered between 2008 and 2013 (λ = 0.966); the population at Yawzi Point declined from 1988 to 2003 without signs of recovery. Projections suggest a continuation of recent conditions could allow O. annularis at Tektite to retain ∼ 9% cover after 100 yr, but with a return to the rates of growth and survival of 1993–1998, it could attain coverage similar to that of 1988 (33%) in ∼ 15 yr.

In early years photos were analyzed with less refined taxonomic classsification. This reference table may be used to aggregate taxa to align with coarse analysis. Use this table to define sub-categories and super-categories such as the M. annularis complex. This is a reference dataset containing the taxonomic classifications, groupings of taxonomic classifications, and functional groups. It has been updated in accordance with Budd, et al., 2012.

Intraspecific competition influences population and community dynamics and occurs via two mechanisms. Exploitative competition is an indirect effect that occurs through use of a shared resource and depends on resource availability. Interference competition occurs by obstructing access to a resource and may not depend on resource availability. Our study tested whether the strength of interference competition changes with protozoa population density. We grew experimental microcosms of protozoa and bacteria under different combinations of protozoan density and basal resource availability. We then solved a dynamic predator–prey model for parameters of the functional response using population growth rates measured in our experiment. As population density increased, competition shifted from exploitation to interference, and competition was less dependent on resource levels. Surprisingly, the effect of resources was weakest when competition was the most intense. We found that at low population densities, competition was largely exploitative and resource availability had a large effect on population growth rates, but the effect of resources was much weaker at high densities. This shift in competitive mechanism could have implications for interspecific competition, trophic interactions, community diversity, and natural selection. We also tested whether this shift in the mechanism of competition with protozoa density affected the structure of the bacterial prey community. We found that both resources and protozoa density affected the structure of the bacterial prey community, suggesting that competitive mechanism may also affect trophic interactions.

This is a reference dataset containing the site locations, year established, and types of surveys.

These time series data sample percent cover of Scleractinian corals by genus measured from photo quadrats. Percent cover is given for each quadrat, each site, each year from 1987 to 2011.

      Counts of juvenile corals conducted in situ and small colonies less than 4 cm diameter are pooled from all sites. 
      Supplementary data include in situ seawater temperature daily mean from 1989 to 2011. These data were used to create the figures in 
      Edmunds, P.J., 2013, Decadal-scale changes in the community structure of coral reefs in St. John, US Virgin Islands, Marine ecology Progress Series. doi:10.3354/meps10424

These data are evidence of the the long-term dynamics of shallow coral reefs along the south coast of St. John from as early as 1987. These data describe coral reef community structure by density based on the analysis of color photographs. All of these data originate from color images of photoquadrats recorded annually (usually in the summer) from as early as 1987. The data falls into three groups. The two groups that are contained in this data package are (1) Tektite & Yawzi and (2) Random sites. Tektite – this is at 14 m depth on the eastern side of Great Lameshur Bay and is the original site of the Tektite man-in-the sea project in 1969; this project marked the birth of the Virgin Islands Ecological Research Station (later the Virgin Islands Environmental Resource Station) that hosts the field component of the project. The reef in this location consists of a single buttress that has remained dominated by Montastraea anularis since the start of the research (1987). These surveys consist of 30 photoquadrats (1 x 1 m) distributed along three, 10 m transects. Yawzi – this is at 9 m depth and is on the western side of Great Lameshur Bay and has been recorded photographically since 1987. This reef also started the study period dominated by Montastraea annularis, but has degraded much more rapidly that the Tektite site. These surveys consist of 30 photoquadrats (1 x 1 m) distributed along three, 10 m transects. Random sites – were added in 1992 to address the concern that the original sites (Yawzi and Tektite) were selected on “good” areas of reef and, therefore, could only decline in condition. The Random sites were selected using random coordinates in 1992, and consist of 6 sites (at 7-9 m depth) scattered between Cabritte Point and White Point. All lie a little shoreward of Yawzi and Tektite, and have always been characterized by low coral cover (< 10% cover). The surveys consist of 18-40 photoquadrats (0.5 x 0.5 m; with sample size determined by the exposures on a 35 mm cassette versus digital techniques) that are placed at random points along a transect.

These data are evidence of the the long-term dynamics of shallow coral reefs along the south coast of St. John from as early as 1989. These data come from the long term site at 9 m depth known as Yawzi Point. These data are representative of the Video Transects (VT) starting in 1989 (see Edmunds and Wirman 1991, MEPS 78: 201-204). All images analyzed using 200 randoms dots placed at random on their surface and the substratum beneath each dot annotated (~371,800 decisions by Nov 2017). Hurricanes Irma and Maria struck in September 2017. Because of this, sampling was completed in July and November of 2017. Data are available upon request for 1989 (raw data lost), 1992, 1993, and 1994. These images were analyzed with a coarser resolution that is not consistent with the current format.

This dataset contains the percentage cover of all stony corals (Scleractinia, pooled among genera) and other major groups analyzed from 0.5 x 0.5 m photographic quadrats at the Backreef habitat at the Moorea Coral Reef LTER, French Polynesia. This survey time series began in 2005 and is repeated each year in April. Functional groups counted are: Scleractinian corals, Macroalgae, Crustose Coralline Algae / Bare Space, Soft Corals, Hydrocorals ( Millepora ), Algal Turf and Sand. The coral community was sampled photographically in all represented habitats surrounding the island: Fringing Reef, Lagoon, and Outer Reef. This dataset contains only Lagoon (Backreef) data (see knb-lter-mcr.4 for the other habitats) and is structured in a repeated-measures protocol to allow a statistical contrast of sites, shores and times. Community structure was determined through a coarse analysis of the benthic community, initially completed in situ (2005), but using photoquadrats from 2006. There are quadrats analyzed at each of five areas within each site, and the areas are revisited (but not the quadrats) each year to support the repeated measures design. There are two tables available, providing different views of the same data: a long table having all values in one column and a wide table having a separate column for each observed object. Detailed methods are available in the protocols section.

This data package is formatted as an ecocomDP (Ecological Community Data Pattern). For more information on ecocomDP see https://github.com/EDIorg/ecocomDP. This Level 1 data package was derived from the Level 0 data package found here: https://pasta.lternet.edu/package/metadata/eml/knb-lter-mcr/1038/10. The abstract below was extracted from the Level 0 data package and is included for context: This dataset contains the percentage cover of all stony corals (Scleractinia, pooled among genera) and other major groups analyzed from 0.5 x 0.5 m photographic quadrats at the Backreef habitat at the Moorea Coral Reef LTER, French Polynesia. This survey time series began in 2005 and is repeated each year in April. Functional groups counted are: Scleractinian corals, Macroalgae, Crustose Coralline Algae / Bare Space, Soft Corals, Hydrocorals (Millepora), Algal Turf and Sand. The coral community was sampled photographically in all represented habitats surrounding the island: Fringing Reef, Lagoon, and Outer Reef. This dataset contains only Lagoon (Backreef) data (see knb-lter-mcr.4 for the other habitats) and is structured in a repeated-measures protocol to allow a statistical contrast of sites, shores and times. Community structure was determined through a coarse analysis of the benthic community, initially completed in situ (2005), but using photoquadrats from 2006. There are quadrats analyzed at each of five areas within each site, and the areas are revisited (but not the quadrats) each year to support the repeated measures design. There are two tables available, providing different views of the same data: a long table having all values in one column and a wide table having a separate column for each observed object. Detailed methods are available in the protocols section. This material is based upon work supported by the U.S. National Science Foundation under Grant No. OCE 16-37396 (and earlier awards) as well as a generous gift from the Gordon and Betty Moore Foundation. Research was completed under permits issued by the French Polynesian Government (Délégation à la Recherche) and the Haut-commissariat de la République en Polynésie Francaise (DTRT) (Protocole d'Accueil 2005-2018). This work represents a contribution of the Moorea Coral Reef (MCR) LTER Site.

This data package is formatted as a Darwin Core Archive (DwC-A, event core). For more information on Darwin Core see https://www.tdwg.org/standards/dwc/. This Level 2 data package was derived from the Level 1 data package found here: https://pasta.lternet.edu/package/metadata/eml/edi/357/2, which was derived from the Level 0 data package found here: https://pasta.lternet.edu/package/metadata/eml/edi/291/2. The abstract below was extracted from the Level 0 data package and is included for context: These data are evidence of the the long-term dynamics of shallow coral reefs along the south coast of St. John from as early as 1987. These data describe coral reef community structure as percent cover based on the analysis of color photographs. All of these data originate from color images of photoquadrats recorded annually (usually in the summer) from as early as 1987. The data falls into three groups. The two groups that are contained in this data package are (1) Tektite & Yawzi and (2) Random sites. The juvenile coral density is packaged separately. Tektite – this is at 14 m depth on the eastern side of Great Lameshur Bay and is the original site of the Tektite man-in-the sea project in 1969; this project marked the birth of the Virgin Islands Ecological Research Station (later the Virgin Islands Environmental Resource Station) that hosts the field component of the project. The reef in this location consists of a single buttress that has remained dominated by Montastraea anularis since the start of the research (1987). These surveys consist of 30 photoquadrats (1 x 1 m) distributed along three, 10 m transects. Yawzi – this is at 9 m depth and is on the western side of Great Lameshur Bay and has been recorded photographically since 1987. This reef also started the study period dominated by Montastraea annularis, but has degraded much more rapidly that the Tektite site. These surveys consist of 30 photoquadrats (1 x 1 m) distributed along three, 10 m transects. Random sites – were added in 1992 to address the concern that the original sites (Yawzi and Tektite) were selected on “good” areas of reef and, therefore, could only decline in condition. The Random sites were selected using random coordinates in 1992, and consist of 6 sites (at 7-9 m depth) scattered between Cabritte Point and White Point. All lie a little shoreward of Yawzi and Tektite, and have always been characterized by low coral cover (< 10% cover). The surveys consist of 18-40 photoquadrats (0.5 x 0.5 m; with sample size determined by the exposures on a 35 mm cassette versus digital techniques) that are placed at random points along a transect. This project focuses on the long-term community dynamics of shallow coral reefs on the south shore of St. John. The project began in 1987 and consists of permanently marked areas that are photographed annually for the analysis of benthic community structure and areas that are censused annually for the density of juvenile corals. All of the work takes place on reefs at less than 14 m depth, and virtually all of the study sites fall between Cabritte Point to the east, and White Point to the west. The project is independent of, but complimentary to, the larger-scale reef monitoring program conducted by the Virgin Islands National Park. The project described here is an independent academic effort led by Dr. Peter Edmunds from California State University, Northridge. The objective of this study is to describe coral reef community dynamics in great detail from a small area to first, elucidate the patterns of change in key components of the benthic coral reefs, and second, to test for processes that drive the changes observed. The core of the project relies on high resolution digital images that have been recorded at least annually since December 1987, and are available here as a invaluable photographic archive for further analysis and to corroborate existing numerical descriptions. In addition to the photographs, the density of juvenile corals has been recorded at multiple sites since 1994.

This dataset contains the percentage cover of the stony corals (Scleractinia) and other major groups analyzed from 0.5 x 0.5 m photographic quadrats in several reef habitats at the Moorea Coral Reef LTER, French Polynesia. This survey has been repeated annually in April since 2005. There are two tables available, providing different views of the same data: a long table having all values in one column and a wide table having a separate column for each dependent variable. Functional groups (i.e., dependent variables) counted are: Scleractinian Corals (by genus where appropriate, see methods), Macroalgae, Crustose Coralline Algae / Bare Space, Soft Corals, Hydrocorals (Millepora), Algal Turf and Sand. The coral community was sampled photographically in all habitats surrounding the island: Fringing Reef, Lagoon (Backreef), and Outer Reef (Forereef.) The sampling regime consists of a repeated-measures protocol in each habitat, and is structured by habitat to allow a statistical contrast of sites, shores, times, and in the case of the outer reef, depths. Detailed methods are available in the protocols section. This material is based upon work supported by the U.S. National Science Foundation under Grant No. OCE 16-37396 (and earlier awards) as well as a generous gift from the Gordon and Betty Moore Foundation. Research was completed under permits issued by the French Polynesian Government (Délégation à la Recherche) and the Haut-commissariat de la République en Polynésie Francaise (DTRT) (Protocole d'Accueil 2005-2022). This work represents a contribution of the Moorea Coral Reef (MCR) LTER Site.

These data describe the abundance of settler-stage three-spot dascyllus (Dascyllus trimaculatus), a planktivorous damselfish to their juvenile microhabitat, the sea anemone Heteractis magnifica.
Surveys were begun in 1993, and, except for 1994, have been conducted daily each year between June and September on a reef adjacent to the UC Berkeley Gump Research Station in Cooks Bay on the north shore of the island of Moorea in French Polynesia.

This data package is formatted as an ecocomDP (Ecological Community Data Pattern). For more information on ecocomDP see https://github.com/EDIorg/ecocomDP. This Level 1 data package was derived from the Level 0 data package found here: https://pasta.lternet.edu/package/metadata/eml/knb-lter-mcr/4/38. The abstract below was extracted from the Level 0 data package and is included for context: This dataset contains the percentage cover of the stony corals (Scleractinia) and other major groups analyzed from 0.5 x 0.5 m photographic quadrats in several reef habitats at the Moorea Coral Reef LTER, French Polynesia. This survey has been repeated annually in April since 2005. There are two tables available, providing different views of the same data: a long table having all values in one column and a wide table having a separate column for each dependent variable. Functional groups (i.e., dependent variables) counted are: Scleractinian Corals (by genus where appropriate, see methods), Macroalgae, Crustose Coralline Algae / Bare Space, Soft Corals, Hydrocorals (Millepora), Algal Turf and Sand. The coral community was sampled photographically in all habitats surrounding the island: Fringing Reef, Lagoon (Backreef), and Outer Reef (Forereef.) The sampling regime consists of a repeated-measures protocol in each habitat, and is structured by habitat to allow a statistical contrast of sites, shores, times, and in the case of the outer reef, depths. Detailed methods are available in the protocols section. This material is based upon work supported by the U.S. National Science Foundation under Grant No. OCE 16-37396 (and earlier awards) as well as a generous gift from the Gordon and Betty Moore Foundation. Research was completed under permits issued by the French Polynesian Government (Délégation à la Recherche) and the Haut-commissariat de la République en Polynésie Francaise (DTRT) (Protocole d'Accueil 2005-2020). This work represents a contribution of the Moorea Coral Reef (MCR) LTER Site.

These data describe the abundance of adult-stage three-spot dascyllus (Dascyllus trimaculatus), a planktivorous damselfish, and their juvenile microhabitat, the sea anemone Heteractis magnifica. Surveys were begun in 1992 and have been conducted two to four times annually by the same observer in the lagoons of the north shore of the island of Moorea in French Polynesia.