Effects of land-based fish farm effluent on the morphology and growth of Ascophyllum nodosum (Fucales, Phaeophyceae) in southwestern Nova Scotia

White, Katelyn L.,Kim, Jang-Kyun,Garbary, David J. The Korean Society of Phycology 2011 ALGAE Vol.26 No.3

Phenotypic plasticity was examined in the economically and ecologically important brown alga Ascophyllum nodosum in southwestern Nova Scotia, considering specifically how nutrient loading affected its vegetative and reproductive features. To determine this, we examined morphometric changes in A. nodosum from two sites receiving direct effluent impacts from a land-based finfish aquaculture facility and from two control sites, approximately 2 km away from the aquaculture facility in opposite directions. Fronds from test sites were significantly younger than from control sites (5 y vs. 8 y); however, fronds from farm sites were significantly larger (219 g vs. 90 g) because of their higher growth rates. Thalli from farm sites had greater reproductive potential, as shown by numbers of receptacle initials (797 initials vs. 281 initials). These results suggest limited nutrient inflows from land-based aquaculture may positively affect adjacent Ascophyllum populations by inducing higher growth rates. We conclude that the coordination of effluent management from land-based aquaculture with natural resource harvesting of A. nodosum may be beneficial. Further study is necessary to determine the limits of nutrient loading for this potentially beneficial outcome.

Effects of land-based fish farm effluent on the morphology and growth of Ascophyllum nodosum (Fucales, Phaeophyceae) in southwestern Nova Scotia

Katelyn L. White,Jang Kyun Kim,David J. Garbary 한국조류학회I 2011 ALGAE Vol.26 No.3

Phenotypic plasticity was examined in the economically and ecologically important brown alga Ascophyllum nodosum in southwestern Nova Scotia, considering specifically how nutrient loading affected its vegetative and reproductive features. To determine this, we examined morphometric changes in A. nodosum from two sites receiving direct effluent impacts from a land-based finfish aquaculture facility and from two control sites, approximately 2 km away from the aquaculture facility in opposite directions. Fronds from test sites were significantly younger than from control sites (5y vs. 8 y); however, fronds from farm sites were significantly larger (219 g vs. 90 g) because of their higher growth rates. Thalli from farm sites had greater reproductive potential, as shown by numbers of receptacle initials (797 initials vs. 281initials). These results suggest limited nutrient inflows from land-based aquaculture may positively affect adjacent Ascophyllum populations by inducing higher growth rates. We conclude that the coordination of effluent management from land-based aquaculture with natural resource harvesting of A. nodosum may be beneficial. Further study is necessary to determine the limits of nutrient loading for this potentially beneficial outcome.

Systemic and Adipose Tissue Redox Status in Sprague-Dawley Rats Fed Normal- and High-Fat Diets Supplemented with Lycopene

Katelyn E. Senkus,Libo Tan,Kristi M. Crowe-White 한국식품영양과학회 2021 Journal of medicinal food Vol.24 No.4

Dietary patterns high in fat influence local and systemic oxidative stress through adipose tissue (AT) accrual and increased reactive oxygen species generation. Lycopene, a carotenoid with antioxidant functionality, may mitigate excess oxidative stress, yet the lipophilic nature of this compound may limit its functionality if sequestered by AT. Thus, it is critical to elucidate whether lycopene's efficacy is limited based on adiposity. The purpose of this study was to investigate the influence of lycopene-supplemented normal- and high-fat diets on systemic and AT redox status. Male Sprague-Dawley rats (n = 18) were fed a 30% normal-fat (NFD) or 60% high-fat (HFD) purified diet supplemented with 100 mg of lycopene/day. Body weight and visceral AT mass, as well as serum and AT lycopene, lipid peroxides, and antioxidant capacity (AC), were assessed after 3, 7, and 10 weeks of supplementation. At week 10, AT mass was significantly higher (P = .028) in the HFD group, yet there were no significant differences in serum or AT lycopene concentrations or lipid peroxides between groups. Additionally, AT in the HFD group exhibited significantly greater lipophilic AC (27.6% higher, P = .031). Results suggest that excess adiposity did not negatively influence circulating lycopene, nor did it limit its antioxidant functionality.

Temporal and spatial variation in the distribution of life history phases of Chondrus crispus (Gigartinales, Rhodophyta)

Garbary, David J.,Tompkins, Elizabeth,White, Katelyn,Corey, Peter,Kim, Jang-K. The Korean Society of Phycology 2011 ALGAE Vol.26 No.1

Thirty populations of Chondrus crispus Stackhouse from Nova Scotia were collected during the years 1993 to 2011. Taken from estuaries, wave exposed open coasts, high intertidal rock pools and shallow subtidal habitats, the populations were evaluated for relative abundance of tetrasporophytic and gametophytic life history phases. Over 2,800 thalli were characterized using the resorcinol-acetal test to distinguish the kappa- and lambda-carrageenan containing fronds of gametophytes and tetrasporophytes, respectively. These populations had $77{\pm}5%$ gametophytes (mean ${\pm}95%$ confidence interval), with most populations having gametophyte : sporophyte ratios ranging from 2 : 1 to 9 : 1. No population had a dominance of tetrasporophytes, although two populations had 1 : 1 ratios. A meta-analysis of our data along with previously published accounts showed no significant changes in gametophyte dominance with respect to hypothesized gradients of wave exposure, salinity, or water depth. Significant changes occurred in ratios at five sites where replicate sampling occurred in different years. We conclude that C. crispus in Maritime Canada has a natural ratio of 3 : 1 or greater in stable conditions, and that lower ratios represent recovery from disturbance in which bare substratum is created that is subsequently colonized by carpospores from remaining gametophytic thalli.

Temporal and spatial variation in the distribution of life history phases of Chondrus crispus (Gigartinales, Rhodophyta)

David J. Garbary,Elizabeth Tompkins,Katelyn White,Peter Corey,김장균 한국조류학회I 2011 ALGAE Vol.26 No.1

Thirty populations of Chondrus crispus Stackhouse from Nova Scotia were collected during the years 1993 to 2011. Taken from estuaries, wave exposed open coasts, high intertidal rock pools and shallow subtidal habitats, the populations were evaluated for relative abundance of tetrasporophytic and gametophytic life history phases. Over 2,800 thalli were characterized using the resorcinol-acetal test to distinguish the kappa- and lambda-carrageenan containing fronds of gametophytes and tetrasporophytes, respectively. These populations had 77 ± 5% gametophytes (mean ± 95% confidence interval), with most populations having gametophyte : sporophyte ratios ranging from 2 : 1 to 9 : 1. No population had a dominance of tetrasporophytes, although two populations had 1 : 1 ratios. A meta-analysis of our data along with previously published accounts showed no significant changes in gametophyte dominance with respect to hypothesized gradients of wave exposure, salinity, or water depth. Significant changes occurred in ratios at five sites where replicate sampling occurred in different years. We conclude that C. crispus in Maritime Canada has a natural ratio of 3 : 1 or greater in stable conditions, and that lower ratios represent recovery from disturbance in which bare substratum is created that is subsequently colonized by carpospores from remaining gametophytic thalli.

Population ecology of Palmaria palmata (Palmariales, Rhodophyta) from harvested and non-harvested shores on Digby Neck, Nova Scotia, Canada

Garbary, David J.,Beveridge, Leah F.,Flynn, Andrea D.,White, Katelyn L. The Korean Society of Phycology 2012 ALGAE Vol.27 No.1

Population ecology of Palmaria palmata is described from the intertidal zone of Digby Neck and adjacent islands of Nova Scotia. The primary objectives were: to evaluate the difference in habitat specialization and population structure of P. palmata between harvest and non-harvest shores, and to characterize differences in thallus structure and frond sizes between epilithic and epiphytic populations. Harvest shores were gently sloping boulder fields with boulders typically about 0.5-1.0 m with dense cover of P. palmata on many of the rocks. Non-harvest shores (with or without P. palmata) consisted of boulders that were smaller or larger than harvest shores, or bedrock; when P. palmata was present on nonharvest sites it was typically epiphytic on other algae (e.g., Fucus spp., Mastocarpus stellatus, Devaleraea ramentacea). Harvestable epiphytic populations occurred only in high current areas. While there was little difference in average cover of P. palmata harvest and non-harvest shores ($31.2{\pm}13.7%$ vs. $19.4{\pm}7.3%$, mean ${\pm}$ standard deviation [SD]), the cover of P. palmata on harvest shores was highly skewed such that individual boulders often had >90% cover while adjacent rocks had little. Frond length of large fronds was greater on harvested shores, and mean frond density ($g\;m^{-2}$) was three times higher than the mean density on the non-harvested shores. Frond lengths of entire epiphytic and epilithic frond complements of 119 thalli from harvest beaches showed no difference in mean size of the largest fronds, and no difference in frond number per holdfast when epiphytic and epilithic thalli were compared.

Population ecology of Palmaria palmata (Palmariales, Rhodophyta) from harvested and non-harvested shores on Digby Neck, Nova Scotia, Canada

David J. Garbary,Leah F. Beveridge,Andrea D. Flynn,Katelyn L. White 한국조류학회I 2012 ALGAE Vol.27 No.1

Population ecology of Palmaria palmata is described from the intertidal zone of Digby Neck and adjacent islands of Nova Scotia. The primary objectives were: to evaluate the difference in habitat specialization and population structure of P. palmata between harvest and non-harvest shores, and to characterize differences in thallus structure and frond sizes between epilithic and epiphytic populations. Harvest shores were gently sloping boulder fields with boulders typically about 0.5-1.0 m with dense cover of P. palmata on many of the rocks. Non-harvest shores (with or without P. palmata)consisted of boulders that were smaller or larger than harvest shores, or bedrock; when P. palmata was present on nonharvest sites it was typically epiphytic on other algae (e.g., Fucus spp., Mastocarpus stellatus, Devaleraea ramentacea). Harvestable epiphytic populations occurred only in high current areas. While there was little difference in average cover of P. palmata harvest and non-harvest shores (31.2 ± 13.7% vs. 19.4 ± 7.3%, mean ± standard deviation [SD]), the cover of P. palmata on harvest shores was highly skewed such that individual boulders often had >90% cover while adjacent rocks had little. Frond length of large fronds was greater on harvested shores, and mean frond density (g m-2) was three times higher than the mean density on the non-harvested shores. Frond lengths of entire epiphytic and epilithic frond complements of 119 thalli from harvest beaches showed no difference in mean size of the largest fronds, and no difference in frond number per holdfast when epiphytic and epilithic thalli were compared.