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• 251. [Article] RAIN: Journal of Appropriate Technology

  Volume 2, Number 9 Inside: Special Northwest Habitat Issue RAIN began in October 1974 as a publication of ECO-NET, an environmental education network funded by the Hill Foundation and an Environmental ...

  Citation × Citation Citation Abstract Copy Title: RAIN: Journal of Appropriate Technology Author: ECO-NET Year: 1976 Volume 2, Number 9 Inside: Special Northwest Habitat Issue RAIN began in October 1974 as a publication of ECO-NET, an environmental education network funded by the Hill Foundation and an Environmental Education grant. Its office was based in the Environmental Education Center at Portland State University. With a focus on the Pacific Northwest, particularly Oregon, RAIN originally described itself as a “bulletin board” with an “emphasis on environmental/energy related and communications kinds of information” and interested in “the evolutionary possibilities of inter-disciplinary connections.” Title: RAIN: Journal of Appropriate Technology Author: ECO-NET Year: 1976 Volume 2, Number 9 Inside: Special Northwest Habitat Issue RAIN began in October 1974 as a publication of ECO-NET, an environmental education network funded by the Hill Foundation and an Environmental Education grant. Its office was based in the Environmental Education Center at Portland State University. With a focus on the Pacific Northwest, particularly Oregon, RAIN originally described itself as a “bulletin board” with an “emphasis on environmental/energy related and communications kinds of information” and interested in “the evolutionary possibilities of inter-disciplinary connections.” Close

• 252. [Article] Coastal Sediment Elevation Change Following Anthropogenic Mangrove Clearing

  Coastal mangrove forests along tropical shorelines serve as an important interface between land and sea. They provide a physical buffer protecting the coastline from erosion and act as sediment “traps” ...

  Citation × Citation Citation Abstract Copy Title: Coastal Sediment Elevation Change Following Anthropogenic Mangrove Clearing Author: Hayden, Heather Lyn, Granek, Elise F. Year: 2015 Coastal mangrove forests along tropical shorelines serve as an important interface between land and sea. They provide a physical buffer protecting the coastline from erosion and act as sediment “traps” catching terrestrial sediment, thus preventing smothering of subtidal coral reefs. Coastal development that removes mangrove habitat may impact adjacent nearshore coral reefs through sedimentation and nutrient loading. We examined differences in sediment elevation change between patches of open-coast intact and anthropogenically cleared red mangroves (Rhizophora mangle) on the east side of Turneffe Atoll, Belize, to quantify changes following mangrove clearing. Samples were collected over a 24 month period at five study sites, each containing paired intact (+mangrove) and cleared (-mangrove) plots. Five sediment elevation pins were deployed in each plot: behind areas cleared of mangroves (-mangrove) and behind adjacent intact mangroves (+mangrove). Sediment elevation increased at intact mangrove sites (M= +3.83 mm, SE=0.95) whereas cleared mangrove areas suffered elevation loss (M= -7.30 mm, SE=3.38). Mangroves inshore of partial or continuous gaps in the adjacent fringing reefs had higher rates of elevation loss (M=-15.05mm) than mangroves inshore of continuous fringing reefs (M=-1.90mm). Our findings provide information on potential effects of mangrove clearing and the role of offshore habitat characteristics on coastal sediment trapping and maintenance of sediment elevation by mangroves. With implications for coastline capacity to adjust to sea level rise, these findings are relevant to management of coastal fringing mangrove forests across the Caribbean. Title: Coastal Sediment Elevation Change Following Anthropogenic Mangrove Clearing Author: Hayden, Heather Lyn, Granek, Elise F. Year: 2015 Coastal mangrove forests along tropical shorelines serve as an important interface between land and sea. They provide a physical buffer protecting the coastline from erosion and act as sediment “traps” catching terrestrial sediment, thus preventing smothering of subtidal coral reefs. Coastal development that removes mangrove habitat may impact adjacent nearshore coral reefs through sedimentation and nutrient loading. We examined differences in sediment elevation change between patches of open-coast intact and anthropogenically cleared red mangroves (Rhizophora mangle) on the east side of Turneffe Atoll, Belize, to quantify changes following mangrove clearing. Samples were collected over a 24 month period at five study sites, each containing paired intact (+mangrove) and cleared (-mangrove) plots. Five sediment elevation pins were deployed in each plot: behind areas cleared of mangroves (-mangrove) and behind adjacent intact mangroves (+mangrove). Sediment elevation increased at intact mangrove sites (M= +3.83 mm, SE=0.95) whereas cleared mangrove areas suffered elevation loss (M= -7.30 mm, SE=3.38). Mangroves inshore of partial or continuous gaps in the adjacent fringing reefs had higher rates of elevation loss (M=-15.05mm) than mangroves inshore of continuous fringing reefs (M=-1.90mm). Our findings provide information on potential effects of mangrove clearing and the role of offshore habitat characteristics on coastal sediment trapping and maintenance of sediment elevation by mangroves. With implications for coastline capacity to adjust to sea level rise, these findings are relevant to management of coastal fringing mangrove forests across the Caribbean. Close

• 253. [Article] Biogeography and species density distributions of Tasmanian mammals

  Separated from mainland Australia by the Bass Strait, Tasmania has acted as an island preserve maintaining large populations of many mammalian species presently uncommon, rare, or extinct on mainland Australia. There ...

  Citation × Citation Citation Abstract Copy Title: Biogeography and species density distributions of Tasmanian mammals Author: Bevers, Jerry E. Year: 1990 Separated from mainland Australia by the Bass Strait, Tasmania has acted as an island preserve maintaining large populations of many mammalian species presently uncommon, rare, or extinct on mainland Australia. There are few studies of Tasmanian mammal distributions. Recent distributional maps, based on information from surveys and mammal specimens, allowed for an investigation of the species density distributions of the terrestrial mammals of Tasmania. Compilation of species' distributional information into species density distributions provides an overview as to which areas may provide the most significant habitat for the greatest number of species; what geographic variations may influence species distributions; and which regions remain least surveyed for mammalian species in Tasmania. Title: Biogeography and species density distributions of Tasmanian mammals Author: Bevers, Jerry E. Year: 1990 Separated from mainland Australia by the Bass Strait, Tasmania has acted as an island preserve maintaining large populations of many mammalian species presently uncommon, rare, or extinct on mainland Australia. There are few studies of Tasmanian mammal distributions. Recent distributional maps, based on information from surveys and mammal specimens, allowed for an investigation of the species density distributions of the terrestrial mammals of Tasmania. Compilation of species' distributional information into species density distributions provides an overview as to which areas may provide the most significant habitat for the greatest number of species; what geographic variations may influence species distributions; and which regions remain least surveyed for mammalian species in Tasmania. Close

• 254. [Article] The effect of salinity on habitat selection of two Oregon chiton species (Katharina tunicata and Mopalia hindsii)

  Adult specimens of Katharina tunicata (mean weight = 10.23 grams) and Mopalia hindsii (mean weight = 10.90 grams) were tested for osmotic stress tolerance and oxygen consumption rates in a series of salinities ...

  Citation × Citation Citation Abstract Copy Title: The effect of salinity on habitat selection of two Oregon chiton species (Katharina tunicata and Mopalia hindsii) Author: Rostal, David Carl Year: 1986 Adult specimens of Katharina tunicata (mean weight = 10.23 grams) and Mopalia hindsii (mean weight = 10.90 grams) were tested for osmotic stress tolerance and oxygen consumption rates in a series of salinities (120%, 100%, 80%, 60%, and 40% seawater) at 11°C and 16L:8D photoperiod. K. tunicata and M. hindsii displayed similar trends in percent body weight variation and volume regulatory responses to osmotic stress. However, K. tunicata experienced a significantly higher percent body weight increase than did M. hindsii in response to hypo-osmotic conditions (80%, 60%, and 40% seawater). The mean rates of oxygen consumption per salinity for the two species were not significantly different. Both species, however, showed reduced oxygen consumption rates and significantly increased weight gain in 40% seawater. SEM comparisons of radulae, ctenidia, and shape of the pallial groove revealed no significant differences between the species relevant to differences observed in habitat selection. Title: The effect of salinity on habitat selection of two Oregon chiton species (Katharina tunicata and Mopalia hindsii) Author: Rostal, David Carl Year: 1986 Adult specimens of Katharina tunicata (mean weight = 10.23 grams) and Mopalia hindsii (mean weight = 10.90 grams) were tested for osmotic stress tolerance and oxygen consumption rates in a series of salinities (120%, 100%, 80%, 60%, and 40% seawater) at 11°C and 16L:8D photoperiod. K. tunicata and M. hindsii displayed similar trends in percent body weight variation and volume regulatory responses to osmotic stress. However, K. tunicata experienced a significantly higher percent body weight increase than did M. hindsii in response to hypo-osmotic conditions (80%, 60%, and 40% seawater). The mean rates of oxygen consumption per salinity for the two species were not significantly different. Both species, however, showed reduced oxygen consumption rates and significantly increased weight gain in 40% seawater. SEM comparisons of radulae, ctenidia, and shape of the pallial groove revealed no significant differences between the species relevant to differences observed in habitat selection. Close

• 255. [Article] Bayesian Methods for Comparing Species Physiological and Ecological Response Curves

  Many ecological questions require information on species' optimal conditions or critical limits along environmental gradients. These attributes can be compared to answer questions on niche partitioning, ...

  Citation × Citation Citation Abstract Copy Title: Bayesian Methods for Comparing Species Physiological and Ecological Response Curves Author: Ashcroft, Michael B., Casanova-Katny, Angélica, Mengersen, Kerrie, Rosenstiel, Todd N., Turnbull, Johanna D., Wasley, Jane, Waterman, Melinda J., Zúñiga, Gustavo E., Robinson, Sharon A. Year: 2016 Many ecological questions require information on species' optimal conditions or critical limits along environmental gradients. These attributes can be compared to answer questions on niche partitioning, species coexistence and niche conservatism. However, these comparisons are unconvincing when existing methods do not quantify the uncertainty in the attributes or rely on assumptions about the shape of species' responses to the environmental gradient. The aim of this study was to develop a model to quantify the uncertainty in the attributes of species response curves and allow them to be tested for substantive differences without making assumptions about the shape of the responses. We developed a model that used Bayesian penalised splines to produce and compare response curves for any two given species. These splines allow the data to determine the shape of the response curves rather than making a priori assumptions. The models were implemented using the R2OpenBUGS package for R, which uses Markov Chain Monte Carlo simulation to repetitively fit alternative response curves to the data. As each iteration produces a different curve that varies in optima, niche breadth and limits, the model estimates the uncertainty in each of these attributes and the probability that the two curves are different. The models were tested using two datasets of mosses from Antarctica. Both datasets had a high degree of scatter, which is typical of ecological research. This noise resulted in considerable uncertainty in the optima and limits of species response curves, but substantive differences were found. Schistidium antarcticiwas found to inhabit wetter habitats than Ceratodon purpureus, and Polytrichastrum alpinum had a lower optimal temperature for photosynthesis than Chorisodontium aciphyllum under high light conditions. Our study highlights the importance of considering uncertainty in physiological optima and other attributes of species response curves. We found that apparent differences in optima of 7.5 °C were not necessarily substantive when dealing with noisy ecological data, and it is necessary to consider the uncertainty in attributes when comparing the curves for different species. The model introduced here could increase the robustness of research on niche partitioning, species coexistence and niche conservatism. Title: Bayesian Methods for Comparing Species Physiological and Ecological Response Curves Author: Ashcroft, Michael B., Casanova-Katny, Angélica, Mengersen, Kerrie, Rosenstiel, Todd N., Turnbull, Johanna D., Wasley, Jane, Waterman, Melinda J., Zúñiga, Gustavo E., Robinson, Sharon A. Year: 2016 Many ecological questions require information on species' optimal conditions or critical limits along environmental gradients. These attributes can be compared to answer questions on niche partitioning, species coexistence and niche conservatism. However, these comparisons are unconvincing when existing methods do not quantify the uncertainty in the attributes or rely on assumptions about the shape of species' responses to the environmental gradient. The aim of this study was to develop a model to quantify the uncertainty in the attributes of species response curves and allow them to be tested for substantive differences without making assumptions about the shape of the responses. We developed a model that used Bayesian penalised splines to produce and compare response curves for any two given species. These splines allow the data to determine the shape of the response curves rather than making a priori assumptions. The models were implemented using the R2OpenBUGS package for R, which uses Markov Chain Monte Carlo simulation to repetitively fit alternative response curves to the data. As each iteration produces a different curve that varies in optima, niche breadth and limits, the model estimates the uncertainty in each of these attributes and the probability that the two curves are different. The models were tested using two datasets of mosses from Antarctica. Both datasets had a high degree of scatter, which is typical of ecological research. This noise resulted in considerable uncertainty in the optima and limits of species response curves, but substantive differences were found. Schistidium antarcticiwas found to inhabit wetter habitats than Ceratodon purpureus, and Polytrichastrum alpinum had a lower optimal temperature for photosynthesis than Chorisodontium aciphyllum under high light conditions. Our study highlights the importance of considering uncertainty in physiological optima and other attributes of species response curves. We found that apparent differences in optima of 7.5 °C were not necessarily substantive when dealing with noisy ecological data, and it is necessary to consider the uncertainty in attributes when comparing the curves for different species. The model introduced here could increase the robustness of research on niche partitioning, species coexistence and niche conservatism. Close